期刊文献+
共找到26,355篇文章
< 1 2 250 >
每页显示 20 50 100
Late-Stage Reservoir Formation Effect and Its Dynamic Mechanisms in Complex Superimposed Basins 被引量:5
1
作者 KANG Dejiang PANG Xiongqi +3 位作者 KUANG Jun LUO Xiaorong PANG Hong LEI Lei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2010年第5期1055-1077,共23页
Complex superimposed basins exhibit multi-stage tectonic events and multi-stage reservoir formation; hydrocarbon reservoirs formed in the early stage have generally late-stage genesis characteristics after undergoing ... Complex superimposed basins exhibit multi-stage tectonic events and multi-stage reservoir formation; hydrocarbon reservoirs formed in the early stage have generally late-stage genesis characteristics after undergoing adjustment, reconstruction and destruction of later-stage multiple tectonic events. In this paper, this phenomenon is called the late-stage reservoir formation effect. The late-stage reservoir formation effect is a basic feature of oil and gas-forming reservoirs in complex superimposed basins, revealing not only multi-stage character, relevance and complexity of oil and gas- forming reservoirs in superimposed basins but also the importance of late-stage reservoir formation. Late-stage reservoir formation is not a basic feature of oil and gas forming reservoir in superimposed basins. Multi-stage reservoir formation only characterizes one aspect of oil and gas-forming reservoir in superimposed basins and does not represent fully the complexity of oil and gas-forming reservoir in superimposed basins. We suggest using "late-stage reservoir formation effect" to replace the "late-stage reservoir formation" concept to guide the exploration of complex reservoirs in superimposed basins. Under current geologic conditions, the late-stage reservoir formation effect is represented mainly by four basic forms: phase transformation, scale reconstruction, component variation and trap adjustment. The late-stage reservoir formation effect is produced by two kinds of geologic processes: first, the oil and gas retention function of various geologic thresholds (hydrocarbon expulsion threshold, hydrocarbon migration threshold, and hydrocarbon accumulating threshold) causes the actual time of oil and gas reservoir formation to be later than the time of generation of large amounts of hydrocarbon in a conventional sense, producing the late-stage reservoir formation effect; second, multiple types of tectonic events (continuously strong reconstruction, early-stage strong reconstruction, middle-stage strong reconstruction, late-stage strong reconstruction and long-term stable sedimentation) after oil and gas reservoir formation lead to adjustment, reconstruction and destruction of reservoirs formed earlier, and form new secondary hydrocarbon reservoirs due to the late-stage reservoir formation effect. 展开更多
关键词 superimposed basin late-stage reservoir formation effect late-stage reservoir formation tectonic event geologic threshold
在线阅读 下载PDF
Survey for late-onset hypogonadism among old anti middle-aged males in Shanghai communities 被引量:14
2
作者 Kai Sun GuoTQing Liang +6 位作者 Xiang-Feng Chen Ping Ping Wen-Liang Yao Shi-Jun Zhang Bo Wang Ying-Hao Sun Zheng Li 《Asian Journal of Andrology》 SCIE CAS CSCD 2012年第2期338-340,共3页
This study sought to investigate late-onset hypogonadism (LOH) in old and middle-aged males in Shanghai communities, using symptom score evaluation systems and measurements of sex hormone levels. One thousand cases ... This study sought to investigate late-onset hypogonadism (LOH) in old and middle-aged males in Shanghai communities, using symptom score evaluation systems and measurements of sex hormone levels. One thousand cases of males aged 40-70 years were investigated. The aging male symptoms (AMS) scale and androgen deficiency in aging males (ADAM) questionnaire were used at the beginning of the investigation, followed by measurement of the sex hormone-related factors (total testosterone (TT), free testosterone (fT), sex hormone-binding globulin (SHBG) and bioavailability of testosterone (Bio-T)). There were 977 valid questionnaires. The LOH-positive rates shown by AMS and ADAM were 59.88% and 84.65%, respectively; values increased with the age of the patients. There were 946 results related to sex hormone measurements, which showed the following results: TT was not related to aging (P〉O.05); levels of SHBG increased with age; and fT and Bio-T decreased with age. There was a significant difference in fT between LOH-positive and LOH-negative patients, as shown by the ADAM. In summary, TT levels were not related to aging, even though SHBG did increase while fT and Bio-T decreased with aging. Clinically, the diagnosis of LOH cannot be based on serum TT level. 展开更多
关键词 ADAM AMS late-onset of hypogonadism male aging old and middle-aged males SURVEY
在线阅读 下载PDF
restosterone replacement therapy for late-onsel lypogonadism: current trends in Korea 被引量:8
3
作者 Young Hwii Ko Je Jong Kim 《Asian Journal of Andrology》 SCIE CAS CSCD 2011年第4期563-568,共6页
Testosterone levels in men older than 40 years can decrease at a rate of 1%-2% per year, and reports show that more than 50% of 80-year-old men have testosterone levels consistent with hypogonadism. Late-onset hypogon... Testosterone levels in men older than 40 years can decrease at a rate of 1%-2% per year, and reports show that more than 50% of 80-year-old men have testosterone levels consistent with hypogonadism. Late-onset hypogonadism (LOH) is a clinical and biochemical syndrome associated with advancing age and characterized by typical symptoms of serum testosterone deficiency. In recent decades, the concept of LOH in ageing men has become familiar in European countries and the United States. It is also a topic of interest and debate throughout Korea. However, most of the data regarding advantages or disadvantages of testosterone replacement therapy (TRT) as treatment for LOH have been primarily obtained from studies on Western populations; therefore, studies of the effects of TRT in Asian men, who may have different serum testosterone compared to Western men, are needed. TRT is commonly prescribed in Korea, despite the paucity of studies on the effects of TRT in Asian populations. Data from various TRT studies based on Korean have shown its efficacy in increasing serum testosterone levels and improving subjective symptoms as assessed by questionnaires. Currently, patches and short-acting intramuscular injections are displaced by gels and long-acting formulations. However, to prevent overdiagnosis and overtreatment, indication for TRT should include both low testosterone levels and symptoms and signs of hypogonadism. 展开更多
关键词 ANDROGENS androgenic agents late-onset hypogonadism testosterone replacement therapy
在线阅读 下载PDF
The Relation Between Endogenous Hormones and Late-Germination in Buds of Avrolles Apple 被引量:10
4
作者 QIN Dong WANG Jin-zheng +1 位作者 GUO Jian-min ZHAI Heng 《Agricultural Sciences in China》 CAS CSCD 2009年第5期564-571,共8页
In order to provide the physiological bases for selecting late-germination cultivars that can avoid late frost damage, the very late-germination variety Avrolles (Malus domestica) was used to study the relation betw... In order to provide the physiological bases for selecting late-germination cultivars that can avoid late frost damage, the very late-germination variety Avrolles (Malus domestica) was used to study the relation between the dynamic changes and balance of endogenous hormones and germination time. The concentrations of endogenous GA3, ABA, IAA, and ZR were determined in buds of Avrolles and Judeline (Malus domestica) from dormancy releasing to germination by capillary electrophoresis. The dynamic changes of endogenous hormones concentration in buds of Avrolles and Judeline were similar; but the magnitude and time of the change were significantly different between the two varieties, especially for GA3. GA3 concentration increased with dormancy releasing, then decreased, and increased again before germination in the two varieties. GA3 concentration in Avrolles was 1.72 times that in Judeline at the first peak, the gap increased to 2.22 times at germination. ZR concentration exhibited a continuous increase trend, but it decreased sharply before germination. ZR accumulation in Avrolles took 36 days longer than in Judeline, the peak value was 44% higher than in Judeline. Before germination, ZR concentration in Avrolles was 2.12 times that in Judeline. The differences between IAA and ABA concentration were relatively small in the two varieties, while the ratios of GA3/ABA and (GA3 + IAA + ZR)/ABA in Avrolles were 2.08 and 1.58 times those in Judeline, respectively. The germination of apple bud was regulated by the endogenous hormones. For the late-germination apple Avrolles, its germination requires higher concentration of GA3 and ZR, which leads to the high ratios of GA3/ABA and (GA3+ IAA+ ZR)/ABA. 展开更多
关键词 Malus domestica cv. Avrolles Malus domestica cv. Judeline late-germination endogenous hormone
在线阅读 下载PDF
Characteristics of Late-Quaternary Activity and Seismic Risk of the Northeastern Section of the Longmenshan Fault Zone 被引量:6
5
作者 WANG Mingming ZHOU Bengang +2 位作者 YANG Xiaoping XIE Chao GAO Xianglin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2013年第6期1674-1689,共16页
Following the 2008 Wenchuan M8 earthquake,the seismic risk of the northeastern section of the Longmenshan fault zone and the adjacent Hanzhong basin has become an issue that receives much concern.It is facing,however,... Following the 2008 Wenchuan M8 earthquake,the seismic risk of the northeastern section of the Longmenshan fault zone and the adjacent Hanzhong basin has become an issue that receives much concern.It is facing,however,the problem of a lack of sufficient data because of little previous work in these regions.The northeastern section of the Longmenshan fault zone includes three major faults:the Qingchuan fault,Chaba-Lin'ansi fault,and Liangshan south margin fault,with the Hanzhong basin at the northern end.This paper presents investigations of the geometry,motion nature,and activity ages of these three faults,and reveals that they are strike slip with normal faulting,with latest activity in the Late Pleistocene.It implies that this section of the Longmenshan fault zone has been in an extensional setting,probably associated with the influence of the Hanzhong basin.Through analysis of the tectonic relationship between the Longmenshan fault zone and the Hanzhong basin,this work verifies that the Qingchuan fault played an important role in the evolution of the Hanzhong basin,and further studies the evolution model of this basin.Finally,with consideration of the tectonic setting of the Longmenshan fault zone and the Hanzhong basin as well as seismicity of surrounding areas,this work suggests that this region has no tectonic conditions for great earthquakes and only potential strong events in the future. 展开更多
关键词 Seismic risk northeastern Longmenshan fault zone Hanzhong basin late-Quaternary activity
在线阅读 下载PDF
Late-stage Hydrocarbon Accumulation in the Bozhong Depression of the Bohai Bay Basin as Controlled by Neotectonism 被引量:4
6
作者 GONGZaisheng ZHANGGongchengt +1 位作者 CAIDongsheng HEShibin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第3期632-639,共8页
Neotectonism occurred intensively in the Bozhong depression in the Bohai Bay Basin, which was reflected vertically by dramatic subsidence and a number of uplifts and laterally by notable fault movements. This particul... Neotectonism occurred intensively in the Bozhong depression in the Bohai Bay Basin, which was reflected vertically by dramatic subsidence and a number of uplifts and laterally by notable fault movements. This particularity has resulted in the special petroleum geological conditions of the Bozhong depression which are different from those of adjacent lands. For example, the source rocks of the Shahejie Formation were overpressured and hydrocarbon generation occurred in the late stage; the Dongying Formation was deeply buried below the hydrocarbon-generating threshold, therefore there were sufficient oil sources. The rapid subsidence led to starved sedimentation of the Guantao Formation fine sandstone and the regional Minghuazhen Formation lacustrine shale, which formed the Neogene regional reservoir-caprock association. The active faults formed in the neotectonism became passages for oil to migrate from the Paleogene to Neogene. The traps formed by late fault activity and accompanied anticlines provided spaces for the formation of reservoirs. All the above factors match well with one another in the Bozhong depression, providing favorable conditions for the formation of a series of large oilfields in the region 展开更多
关键词 Bozhong depression neotectonism late-stage hydrocarbon accumulation Tanlu fault large oilfields
在线阅读 下载PDF
How to recognize late-onset hypogonadism in men wit sexual dysfunction 被引量:3
7
作者 Giovanni Corona Giulia Rastrelli +2 位作者 Linda Vignozzi Edoardo Mannucci Mario Maggi 《Asian Journal of Andrology》 SCIE CAS CSCD 2012年第2期251-259,共9页
Late-onset hypogonadism (LOH) has been considered the most common form of male hypogonadism with a prevalence of approximately 1 in 100 men. Diagnosis of LOH should be made in symptomatic men with unequivocally low ... Late-onset hypogonadism (LOH) has been considered the most common form of male hypogonadism with a prevalence of approximately 1 in 100 men. Diagnosis of LOH should be made in symptomatic men with unequivocally low serum testosterone (T) levels. However, its clinical presentation is often insidious and difficult to recognize because it is characterized by nonspecific symptoms that make differential diagnosis with physiological ageing problematic. Sexual dysfunction is the most important determinant for medical consultation and the most specific symptom associated with low T. We therefore analysed a consecutive series of 1734 subjects who attended our unit for sexual dysfunction to investigate the associations between low T (different thresholds), sexual parameters, medical history data (delayed puberty, pituitary disease or cryptorchidism) and their physical exam results. Metabolic parameters, in particular waist circumference, display the greatest accuracy in detecting low T. We found that only the association of several symptoms and signs could significantly raise the clinical suspicion of low T. Structured inventories, which cluster together symptoms and signs of hypogonadism, can help clinicians suspect androgen deficiency. In particular, structured interviews, such as ANDROTEST, have been demonstrated to have a greater accuracy when compared to self reported questionnaires in detecting low T levels. 展开更多
关键词 late-onset hypogonadism (LOH) male hypogonadism TESTOSTERONE sexual dysfunction
在线阅读 下载PDF
Erectile function and late-onset hypogonadism symptoms related to lower urinary tract symptom severity in elderly men 被引量:4
8
作者 Ozan Bozkurt Deniz Bolat +10 位作者 Omer Demir Oktay Ucer Ali Sahin Burak Ozcift Abdulkadir Pekta Tahir Turan Bilal H Gümü Ertan Cans Ahmet Bolukbasi Haluk Erol Adil Esenx 《Asian Journal of Andrology》 SCIE CAS CSCD 2013年第6期785-789,I0008,共6页
The aim of this study was to evaluate the relationship between lower urinary tract symptoms (LUTSs), erectile dysfunction (ED) and symptomatic late-onset hypogonadism (SLOH) in ageing men in the Aegean region of... The aim of this study was to evaluate the relationship between lower urinary tract symptoms (LUTSs), erectile dysfunction (ED) and symptomatic late-onset hypogonadism (SLOH) in ageing men in the Aegean region of Turkey. Five hundred consecutive patients 〉40 years old who had been in a steady sexual relationship for the past 6 months and were admitted to one of six urology clinics were included in the study. Serum prostate-specific antigen and testosterone levels and urinary flow rates were measured. All patients filled out the International Prostate Symptom Score and Quality of Life (IPSS-QoL), International Index of Erectile Function (IIEF) and Aging Males' Symptoms (AMS) scale forms. Of the patients, 23.9% had mild LUTSs, 53.3% had moderate LUTSs and 22.8% had severe LUTSs. The total testosterone level did not differ between groups. Additionally, 69.6% had ED. The presence of impotence increased with increasing LUTS severity. Symptomatic late-onset hypogonadism (AMS 〉27) was observed in 71.2% of the patients. The prevalence of severe hypogonadism symptoms increased with the IPSS scores. A correlation analysis revealed that all three questionnaire scores were significantly correlated. In conclusion, LUTS severity is an age-independent risk factor for ED and SLOH. LUTS severity and SLOH symptoms appear to have a strong link that requires etiological and biological clarification in future studies. 展开更多
关键词 ageing male erectile dysfunction lower urinary tract symptoms symptomatic late-onset hypogonadism symptom scores TESTOSTERONE
暂未订购
Effects of long-term androgen replacement therapy on the physical and mental statuses of aging males with late-onset hypogonadism: a multicenter, randomized controlled trial in Japan (EARTH Study) 被引量:3
9
作者 Hiroyuki Konaka Kazuhiro Sugimoto +7 位作者 Hideki Orikasa Teruaki Iwamoto Toshinari Takamura Yoshiyu Takeda Kazuyoshi Shigehara Masashi Iijima Eitetsu Koh Mikio Namiki 《Asian Journal of Andrology》 SCIE CAS CSCD 2016年第1期25-34,共10页
Androgen replacement therapy (ART) efficacy on late-onset hypogonadism (LOH) has been widely investigated in Western countries; however, it remains controversial whether ART can improve health and prolong active l... Androgen replacement therapy (ART) efficacy on late-onset hypogonadism (LOH) has been widely investigated in Western countries; however, it remains controversial whether ART can improve health and prolong active lifestyles. We prospectively assessed long-term ART effects on the physical and mental statuses of aging men with LOH in Japan. The primary endpoint was health-related quality of life assessed by questionnaires. Secondary endpoints included glycemic control, lipid parameters, blood pressure, waist circumference, body composition, muscular strength, International Prostate Symptom Scores (IPSS), International Index of Erectile Function-5 (IIEF-5) scores, and serum prostate-specific antigen levels. Of the 1637 eligible volunteers, 334 patients 〉 40 years with LOH were randomly assigned to either the ART (n = 169) or control groups (n = 165). Fifty-two weeks after the initial treatment, ART significantly affected the role physical subdomain of the short form-36 health survey (SF-36) scale (P= 0.0318). ART was also associated with significant decreases in waist circumstance (P = 0.002) and serum triglyceride (TG) (P = 0.013) and with significant increases in whole-body and leg muscle mass volumes (P= 0.071 and 0.0108, respectively), serum hemoglobin (P 〈 0.001), IPSS voiding subscore (P = 0.0418), and the second question on I IEF-5 (P = 0.0049). There was no significant difference between the groups in terms of severe adverse events. In conclusion, in patients with LOH, long-term ART exerted beneficial effects on Role Physical subdomain of the SF-36 scale, serum TG, waist circumstance, muscle mass volume, voiding subscore of IPSS, and the second question of IIEF-5. We hope our study will contribute to the future development of this area. 展开更多
关键词 androgen replacement therapy health-related quality of life late-onset hypogonadism randomized controlled trial TESTOSTERONE
原文传递
Sulforaphene in Raphanus sativus L. var. caudatus Alef increased in late-bolting stage as well as anticancer activity 被引量:2
10
作者 Piman Pocasap Natthida Weerapreeyakul +1 位作者 Waraporn Tanthanuch Kanjana Thumanu 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2017年第11期998-1004,共7页
Objectives: To evaluate the concentration differences of sulforaphene and sulforaphane at various ages and in different parts of Raphanus sativus L. var. caudatus with respect to their potential cancer preventive effe... Objectives: To evaluate the concentration differences of sulforaphene and sulforaphane at various ages and in different parts of Raphanus sativus L. var. caudatus with respect to their potential cancer preventive effect on HCT116 colon cancer cells.Methods: FTIR–ATR and GC–MS were used to characterize the isothiocyanates in the plant extracts followed by HPLC for quantification. Antiproliferation and apoptosis induction were determined by using MTT assay and flow cytometry, respectively.Results: The respective rank of anticancer activity of Raphanus sativus were as follows:vegetative(3 week) < older rosette(4 week) < early-bolting(5 week) < senescence(7 week) < late-bolting(6 week). The low to high concentration of sulforaphene and sulforaphane occurred in the same stage order.Conclusions: The reproductive parts(flower, pod, and dry seed) of Raphanus sativus have the greatest isothiocyanate concentration, evidenced by a sulforaphene concentration higher than the sulforaphane. This result should inform the selection of the most appropriate harvesting stage and plant part for use as a potential chemopreventive agent. 展开更多
关键词 ISOTHIOCYANATES Sulforaphene SULFORAPHANE Thai rat-tailed radish Anticancer activity late-bolting stage
暂未订购
Late-onset hypogonadism: beyond testosterone 被引量:2
11
作者 Carlo Foresta Aldo E Calogero +2 位作者 Francesco Lombardo Andrea Lenzi Alberto Ferlin 《Asian Journal of Andrology》 SCIE CAS CSCD 2015年第2期236-238,I0008,共4页
Late-onset hypogonadism is defined as a combination of low testosterone (T) levels and typical symptoms and signs. A major area of uncertainty is whether T concentrations are always really sufficient to fully reflec... Late-onset hypogonadism is defined as a combination of low testosterone (T) levels and typical symptoms and signs. A major area of uncertainty is whether T concentrations are always really sufficient to fully reflect Leydig cell (dys)function. Mild testicular alteration could be diagnosed only by additional biochemical markers, such as luteinizing hormone (LH) and 25-hydroxyvitamin D levels. These markers help in identifying the so-called "subclinical" hypogonadism (normal T, high LH levels). Patients with hypogonadism have frequently low levels of 25-hydroxyvitamin D due to impairment of the hydroxylating enzyme CYP2R1 in the testis. However, no data have been published dealing with the best treatment option (cholecalciferol - the Vitamin D precursor, or calcidiol - 25-hydroxylated form of Vitamin D) in these patients. We studied 66 patients with classic hypogonadism (total T [TT] 〈12 nmol I-~, LH 〉 8 IU 1-1) (n = 26) and subclinical hypogonadism (TT 〉 12 nmol I-*, LH 〉 8 IU I-~) (n = 40) and low 25-hydroxyvitamin D (〈50 nmol I-1). Subjects received cholecalciferol (5000 IU per week) (n = 20) or calcidiol (4000 IU per week) (n -- 46), and 25-hydroxyvitamin D and parathyroid hormone (PTH) were evaluated after 3 months of therapy. Supplementation with calcidiol significantly increased 25-hydroxyvitamin D and significantly decreased PI"H levels in both groups of men with hypogonadism (primary, n = 16 and subclinical, n = 30), whereas supplementation with cholecalciferol did not modify their levels. This study shows for the first time that the administration of the 25-hydroxylated form of Vitamin D (calcidiol), and not the administration of the precursor cholecalciferol, restores 25-hydroxyvitamin D levels in subjects with hypogonadism. 展开更多
关键词 insulin-like factor 3 late-onset hypogonadism male hypogonadism TESTOSTERONE Vitamin D
原文传递
Molecular Genetic Analysis of Autosomal Dominant Late-Onset Cataract in a Chinese Family 被引量:1
12
作者 杨国华 钟山 +4 位作者 张先荣 彭碧文 黎俊 柯铁 徐华 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2010年第6期792-797,共6页
Congenital cataract is a highly heterogeneous disorder at both the genetic and the clinical-phenotypic levels.A unique cataract was observed in a 4-generation Chinese family,which was characterized by autosomal domina... Congenital cataract is a highly heterogeneous disorder at both the genetic and the clinical-phenotypic levels.A unique cataract was observed in a 4-generation Chinese family,which was characterized by autosomal dominant inheritance and late-onset.Mutations in the 13 known genes (CRYAA,CRYAB,CRYBB1,CRYBB2,CRYGC,CRYBA1/A3,CRYGD,Connexin50,Connexin46,intrinsic membrane protein LIM2,cytoskeletal protein BFSP2,the major intrinsic protein-MIP and the heat shock factor HSF4) have previously been demonstrated to be the frequent reason for isolated congenital cataracts,but the exact molecular basis and underlying mechanisms of congenital cataract still remain unclear.This study was designed to find whether these 13 genes developed any mutation in the family members and to identify the disease-causing gene.Polymerase chain reaction (PCR) and direct DNA sequence analysis were carried out to detect the 13 genes.The results showed that no mutation causing amino acid alternations was found in these potential candidate genes among all patients in the family,and only several single-nucleotide polymorphisms (SNPs) were identified.A transitional mutation in the fourth intron of CRYBB2 and some silent mutations in the first exon of BFSP2 and CRYGD were found in the cataract family,but further study showed that these mutations could also be found in normal controls.It was concluded that some unidentified genes may underlie the occurrence of late-onset cataract in this family.A genome-wide screening will be carried out in the next study. 展开更多
关键词 CATARACT late-ONSET GENE SEQUENCING MUTATION
暂未订购
Secondary Cones of the Shatsky Rise and Implications for Late-Stage Volcanism Atop Oceanic Plateaus 被引量:1
13
作者 ZHANG Jinchang CHEN Jie HUANG Yanming 《Journal of Ocean University of China》 SCIE CAS CSCD 2019年第5期1115-1122,共8页
Oceanic plateaus are large igneous provinces in the oceans,created by massive underwater eruptions,but their late-stage volcanism is poorly understood.With the addition of recent high-quality bathymetric data to exist... Oceanic plateaus are large igneous provinces in the oceans,created by massive underwater eruptions,but their late-stage volcanism is poorly understood.With the addition of recent high-quality bathymetric data to existing data,286 secondary cones were discovered over Shatsky Rise oceanic plateau.These cones with steeper flank slopes(mean 6.1°±4.4°)and smaller sizes(102–1923 m in height)are morphologically distinct from the plateau,and they are thought to have formed after the main volcanic episodes.Cone height and characteristic height(420 m)are close to seamounts in the Pacific Ocean,whereas greater than those in the Atlantic Ocean.Mean flatness of Shatsky Rise’s cones(0.25±0.20)are similar to that of seamounts in both Pacific and Atlantic Oceans,but notably density in cone distribution(0.56 km^-3)and their mean slope are significantly lower than those of seamounts in the two oceans.Lower slopes of secondary cones within Shatsky Rise may be explained by higher effusion rates of remaining magma.Although cone formation was expected to have a link to rifting by seafloor spreading,weak relationship between cone orientation and magnetic anomaly pattern implies that the expectation is negative.Moreover,weak correlation between the cone height and depth indicates it is not true that volcanic cones grow taller when they occur closer to the massif summits with thicker oceanic crust,which was suggested as the increase in hydraulic pressure.Cone height and flatness are also not strongly related,implying that remaining magma supply was too limited to foster the cones to critical height. 展开更多
关键词 Shatsky RISE oceanic plateau SECONDARY cone late-stage VOLCANISM underwater ERUPTION submarine VOLCANO
在线阅读 下载PDF
Chromospheric activity in several single late-type stars 被引量:1
14
作者 Li-Yun Zhang Qing-Feng Pi Zhong-Zhong Zhu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2015年第2期252-274,共23页
New high-resolution echelle spectra of six single late-type Pleiades-like stars (V368 Cep, EP Eri, DX Leo, GJ 211, PW And and V383 Lac) were obtained with the 2.16 meter telescope at Xinglong Station in 2008-2010. U... New high-resolution echelle spectra of six single late-type Pleiades-like stars (V368 Cep, EP Eri, DX Leo, GJ 211, PW And and V383 Lac) were obtained with the 2.16 meter telescope at Xinglong Station in 2008-2010. Using the spectral subtraction technique, we analyzed our spectroscopic data and calculated the equiva- lent widths of excess emission from several indicators of chromospheric activity (Na I D1, D2, Hoz and Ca II infrared triplet lines). All our results using chromospheric activ- ity indicators confirmed the previous findings. In addition, the maximum amplitudes of chromospheric rotational modulation and the ratio of EW8542/EW8498 were found to rise with increasing v sin i velocity. 展开更多
关键词 stars: chromospheres stars: spectroscopic stars: activity stars: rotation late-TYPE
在线阅读 下载PDF
Palladium-catalyzed late-stage mono-aroylation of the fully substituted pyrazoles via aromatic C-H bond activation 被引量:1
15
作者 Miao-Miao Chen Ling-Yan Shao +3 位作者 Li-Jun Lun Yu-Liang Wu Xiao-Pan Fu Ya-Fei Ji 《Chinese Chemical Letters》 SCIE CAS CSCD 2019年第3期702-706,共5页
The palladium-catalyzed late-stage aroylation of 4-methyl-1,5-diaryl-lH-pyrazole-3-carboxylates has been developed via direct and exclusive mono-Csp^2-H bond activation with broad substrate scope and good functional g... The palladium-catalyzed late-stage aroylation of 4-methyl-1,5-diaryl-lH-pyrazole-3-carboxylates has been developed via direct and exclusive mono-Csp^2-H bond activation with broad substrate scope and good functional group tolerance. A dual-core dimeric palladacycle is confirmed by X-ray single crystal crystallography, and probably serves as an active species in the catalytic cycle. 展开更多
关键词 Palladium-catalysis late-stage FUNCTIONALIZATION AroYlation Fully SUBSTITUTED PYRAZOLES C-H bond activation Cyclopalladated intermediate
原文传递
Late-Stage Ductile Deformation in Xiongdian-Suhe HP Metamorphic Unit, North-Western Dabie Shan, Central China 被引量:2
16
作者 SuoShutian ZhongZengqiu +1 位作者 ZhouHanwen YouZhendong 《Journal of China University of Geosciences》 SCIE CSCD 2004年第3期262-274,共13页
New structural and petrological data unveil a very complicated ductile deformation history of the Xiongdian-Suhe HP metamorphic unit, north-western Dabie Shan, central China. The fine-grained symplectic amphibolite-fa... New structural and petrological data unveil a very complicated ductile deformation history of the Xiongdian-Suhe HP metamorphic unit, north-western Dabie Shan, central China. The fine-grained symplectic amphibolite-facies assemblage and coronal structure enveloping eclogite-facies garnet, omphacite and phengite etc., representing strain-free decompression and retrogressive metamorphism, are considered as the main criteria to distinguish between the early-stage deformation under HP metamorphic conditions related to the continental deep subduction and collision, and the late-stage deformation under amphibolite to greenschist-facies conditions occurred in the post-eclogite exhumation processes. Two late-stages of widely developed, sequential ductile deformations D 3 and D 4, are recognized on the basis of penetrative fabrics and mineral aggregates in the Xiongdian-Suhe HP metamorphic unit, which shows clear, regionally, consistent overprinting relationships. D 3 fabrics are best preserved in the Suhe tract of low post-D 3 deformation intensity and characterized by steeply dipping layered mylonitic amphibolites associated with doubly vergent folds. They are attributed to a phase of tectonism linked to the initial exhumation of the HP rocks and involved crustal shortening with the development of upright structures and the widespread emplacement of garnet-bearing granites and felsic dikes. D 4 structures are attributed to the main episode of ductile extension (D 1 4) with a gently dipping foliation to the north and common intrafolial, recumbent folds in the Xiongdian tract, followed by normal sense top-to-the north ductile shearing (D 2 4) along an important tectonic boundary, the so-called Majiawa-Hexiwan fault (MHF), the westward continuation of the Balifan-Mozitan-Xiaotian fault (BMXF) of the northern Dabie Shan. It is indicated that the two stages of ductile deformation observed in the Xiongdian-Suhe HP metamorphic unit, reflecting the post-eclogite compressional or extrusion wedge formation, the subhorizontal ductile extension and crustal thinning as well as the top-to-the north shearing along the high-angle ductile shear zones responsible for exhumation of the HP unit as a coherent slab, are consistent with those recognized in the Dabie-Sulu UHP and HP metamorphic belts, suggesting that they were closely associated in time and space. The Xiongdian-Suhe HP metamorphic unit thus forms part of the Triassic (250-230 Ma) collision orogenic belt, and can not connect with the South Altun-North Qaidam-North Qinling UHP metamorphic belt formed during the Early Paleozoic (500-400 Ma). 展开更多
关键词 north-western Dabie Shan Xiongdian-Suhe area high-pressure (HP) unit late-stage ductile deformation exhumation layering mylonitic amphibolite.
在线阅读 下载PDF
Late-onset multiple acyl-CoA dehydrogenase deficiency with cardiac syncope: A case report 被引量:3
17
作者 Xue-Qi Pan Xue-Li Chang +4 位作者 Wei Zhang Hua-Xing Meng Jing Zhang Jia-Ying Shi Jun-Hong Guo 《World Journal of Clinical Cases》 SCIE 2020年第5期995-1001,共7页
BACKGROUND Multiple acyl-CoA dehydrogenase deficiency(MADD)is an uncommon autosomal recessive disorder of mitochondrial fatty acid beta-oxidation.Syncope is a transient loss of consciousness due to acute global cerebr... BACKGROUND Multiple acyl-CoA dehydrogenase deficiency(MADD)is an uncommon autosomal recessive disorder of mitochondrial fatty acid beta-oxidation.Syncope is a transient loss of consciousness due to acute global cerebral hypoperfusion.Late-onset MADD with syncope has not been reported previously.CASE SUMMARY We report a 17-year-old girl with exercise intolerance and muscle weakness.She felt palpitation and shortness of breath after short bouts of exercise.She also suffered from a transient loss of consciousness many times.Muscle biopsy showed lipid storage.Genetic mutation analysis indicated a compound heterozygous mutation c.250G>A(p.A84T)and c.872T>G(p.V291G)in the ETFDH gene.The results of Holter electrocardiogram monitoring showed supraventricular tachycardia when the patient experienced a loss of consciousness.After treatment with riboflavin and carnitine,muscle weakness and palpitation symptoms improved rapidly.No loss of consciousness occurred,and the Holter electrocardiogram monitoring was normal.CONCLUSION Late-onset MADD with supraventricular tachycardia can cause cardiac syncope.Carnitine and riboflavin supplement were beneficial for treating the late-onset MADD with cardiac syncope.Attention should be paid to the prevention of cardiac syncope when diagnosing late-onset MADD. 展开更多
关键词 late-onset multiple acyl-CoA dehydrogenase deficiency ETFDH Cardiac syncope Supraventricular tachycardia MITOCHONDRION CARNITINE Case report
暂未订购
A non-invasive,rapid method to genotype late-onset Alzheimer's disease-related apolipoprotein E gene polymorphisms 被引量:1
18
作者 Li Yi Ting Wu +2 位作者 Wenyuan Luo Wen Zhou Jun Wu 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第1期69-75,共7页
The apolipoprotein E gene ε4 allele is considered a negative factor for neural regeneration in late-onset Alzheimer's disease cases. The aim of this study was to establish a non-invasive, rapid method to genotype ap... The apolipoprotein E gene ε4 allele is considered a negative factor for neural regeneration in late-onset Alzheimer's disease cases. The aim of this study was to establish a non-invasive, rapid method to genotype apolipoprotein E gene polymorphisms. Genomic DNA from mouth swab specimens was extracted using magnetic nanoparticles, and genotyping was performed by real-time PCR using TaqMan-BHQ probes. Genotyping accuracy was validated by DNA se- quencing. Our results demonstrate 100% correlation to DNA sequencing, indicating reliability of our protocol. Thus, the method we have developed for apolipoprotein E genotyping is accurate and reliable, and also suitable for genotyping large samples, which may help determine the role of the apolipoprotein E ε4 allele in neural regeneration in late-onset Alzheimer's disease cases. 展开更多
关键词 nerve regeneration NEURODEGENERATION late-onset Alzheimer's disease apolipoprotein Egene real-time PCR DNA sequencing risk factor ALLELE neural regeneration
暂未订购
Altered functional connectivity networks of hippocampal subregions in remitted late-onset depression:a longitudinal resting-state study 被引量:4
19
作者 Zan Wang Yonggui Yuan +4 位作者 Feng Bai Hao Shu Jiayong You Lingjiang Li Zhijun Zhang 《Neuroscience Bulletin》 SCIE CAS CSCD 2015年第1期13-21,共9页
The regional specifi city of hippocampal abnormalities in late-life depression(LLD) has been demonstrated in previous studies. In this study,we sought to examine the functional connectivity(FC) patterns of hippoca... The regional specifi city of hippocampal abnormalities in late-life depression(LLD) has been demonstrated in previous studies. In this study,we sought to examine the functional connectivity(FC) patterns of hippocampal subregions in remitted late-onset depression(r LOD),a special subtype of LLD. Fourteen r LOD patients and 18 healthy controls underwent clinical and cognitive evaluations as well as resting-state functional magnetic resonance imaging scans at baseline and at ~21 months of follow-up. Each hippocampus was divided into three parts,the cornu ammonis(CA),the dentate gyrus,and the subicular complex,and then six seed-based hippocampal subregional networks were established.Longitudinal changes of the six networks over time were directly compared between the rL OD and control groups. From baseline to follow-up,the r LOD group showed a greater decline in connectivity of the left CA to the bilateral posterior cingulate cortex/precuneus(PCC/PCUN),but showed increased connectivity of the right hippocampal subregional networks with the frontal cortex(bilateral medial prefrontal cortex/anterior cingulate cortex and supplementary motor area). Further correlative analyses revealed thatthe longitudinal changes in FC between the left CA and PCC/PCUN were positively correlated with longitudinal changes in the Symbol Digit Modalities Test(r = 0.624,P = 0.017) and the Digit Span Test(r = 0.545,P = 0.044) scores in the r LOD group. These results may provide insights into the neurobiological mechanism underlying the cognitive dysfunction in r LOD patients. 展开更多
关键词 remitted late-onset depression hippocampal subregional network functional connectivity functional magnetic resonance imaging cognitive dysfunction
原文传递
SLC26A4 gene polymorphism and late-onset Alzheimer’s disease in a Han Chinese population from Qingdao,China 被引量:1
20
作者 Jifang Zhang Yantuan Li 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第8期754-759,共6页
In a recent genome-wide association study, the SLC26A4 gene rs2072064 polymorphism was found to be associated with late-onset Alzheimer's disease in Caucasians. Here, we investigated this association in a large North... In a recent genome-wide association study, the SLC26A4 gene rs2072064 polymorphism was found to be associated with late-onset Alzheimer's disease in Caucasians. Here, we investigated this association in a large Northern Han Chinese cohort consisting of 599 sporadic late-onset Alzheimer's disease patients and 598 healthy controls matched for sex and age in a Northern Han Chinese population from Qingdao, China. Genotyping by the polymerase chain reaction-ligase detection reaction revealed that there were significant differences in the genotype (P = 0.017) and allele (P = 0.007) frequencies of the rs2072064 polymorphism between late-onset Alzheimer's disease patients and controls. The A allele of this polymorphism was significantly associated with a reduced risk of late-onset Alzheimer's disease (odds ratio (OR) = 0.792, 95% confidence interval (CI) = 0.670-0.937, P = 0.007). When the data were stratified by the apolipoprotein E E4 status, there was a significant difference only among apolipoprotein E E4 non-carriers (genotypic P = 0.001, allelic P = 0.001). Furthermore, the association between rs2072064 and late-onset Alzheimer's disease remained significant by logistic regression analysis after adjustment for age, gender, and the apolipoprotein E E4 carrier status (dominant model: OR = 0.787, 95% CI = 0.619-1.000, P = 0.050; recessive model: OR = 0.655, 95% CI = 0.448-0.959, P= 0.030; additive model: OR = 0.792, 95% CI = 0.661-0.950, P = 0.012). These findings suggest that SLC26A4 is a susceptibility gene for late-onset Alzheimer's disease in a Northern Han Chinese population from the Qingdao area. 展开更多
关键词 neural regeneration neurodegenerative diseases late-onset Alzheimer's disease SLC26A4 rs2072064 POLYMORPHISM genetic association Han Chinese population apolipoprotein E NEUROREGENERATION
暂未订购
上一页 1 2 250 下一页 到第
使用帮助 返回顶部