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The Effects of Tetrandrine (TT) and Polyvinylpyridine-N-Oxide (PVNO) on Gene Expression of Type Ⅰand Type ⅢCollagens during Experimental Silicosis 被引量:8
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作者 LIU BING-CI HE YU-XIAN +1 位作者 MIAO QING WANG HAI-HUA AND YOU BAO-RONG (Institute of Occupational Medicine, 29 Nan Wei Road,Beijing 100050, China) 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1994年第3期199-204,共6页
In the screening tests of drugs for silicosis in our laboratory, we found that TT, a type of alkaloid isolated from Stephania tetrandra, could inhibit the development of experimental silicosis of rats and the synthesi... In the screening tests of drugs for silicosis in our laboratory, we found that TT, a type of alkaloid isolated from Stephania tetrandra, could inhibit the development of experimental silicosis of rats and the synthesis of collagen in rat lung. Chest X-rays of silicotic patients treaied with TT for 1-3 years showed obvious changes. The silicotic nodules became smallel and shadows became clearer. PVNO was proved to have anti-silicotic effect on animal and clinically. This presentation reports the effect of them on collagen mRNA.Dot blot results showed that 1 (Ⅰ) and 1 (Ⅲ) mRNA levels increased significantly at 60 and 120 days after the rats were exposed to silica dust. The mRNA levels went down at 1 and 3 months after treated by TT and PVNO. In situ hybridization observation revealed that the silver grains of Type Ⅰand Type Ⅲ collagen were scattered within the fibroblasts in cellular nodules and in thickened interstitium of silicosis tissue. The amounts of mRNA silver grains decreased in the lung tissue treated by TT and PVNO. It was suggested that TT and PVNO may inhibil the gene expression of collagen during silicosis 展开更多
关键词 TT on Gene Expression of type Collagens during Experimental Silicosis PVNO The Effects of Tetrandrine and Polyvinylpyridine-N-Oxide and type
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Prediabetes and type 2 diabetes implication in central proliferation and neurogenesis 被引量:2
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作者 Carmen Infante-Garcia Juan Jose Ramos-Rodriguez Monica Garcia-Alloza 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第1期28-29,共2页
Type 2 diabetes (T2D) is an important risk factor for developing dementias, including Alzheimer's disease (AD). Hyperinsulin- emia and glucose intolerance, as features of T2D, might increase the neurodegeneration... Type 2 diabetes (T2D) is an important risk factor for developing dementias, including Alzheimer's disease (AD). Hyperinsulin- emia and glucose intolerance, as features of T2D, might increase the neurodegeneration process, synaptic loss and brain atrophy, leading to cognitive impairment observed in AD. Also, adult neurogenesis seems to be impaired in AD models. Therefore, we have studied morphological alterations, cell proliferation and neurogenesis in the central nervous system (CNS) from a classical model of T2D, the db/db mouse, and in a prediabetes insulin-resistant model, obtained after long-term high fat diet (HFD) administration to C57B1/6 mice. Db/db mice showed an age-dependent cortical and hippocampal atrophy, whereas in HFD mice cortex and hippocampus were preserved. Neurogen- esis and cell proliferation were increased in young db/db mice, when compared with control mice, whereas no differences were detected in the prediabetic model. We also detected significant correlations between metabolic parameters and central atrophy, altered proliferation and neurogenesis in the central nervous system. Altogether these data support that glycaemia control in elderly patients, could help to control central alterations and improve dementia prognosis. 展开更多
关键词 Prediabetes and type 2 diabetes implication in central proliferation and neurogenesis
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Test of the Cosmic Transparency with the Baryon Acoustic Oscillation and Type Ia Supernova Data
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作者 李合昆 吴普训 余洪伟 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第5期149-151,共3页
We use the latest baryon acoustic oscillation and Union 2.1 type Ia supernova data to test the cosmic opacity between different redshift regions without assuming any cosmological models. It is found that the universe ... We use the latest baryon acoustic oscillation and Union 2.1 type Ia supernova data to test the cosmic opacity between different redshift regions without assuming any cosmological models. It is found that the universe may be opaque between the redshift regions 0.35 0.44, 0.44 0.57 and 0.6-0.73 since the best fit values of cosmic opacity in these regions are positive, while a transparent universe is favored in the redshift region 0.57-0.63. However, in general, a transparent universe is still consistent with observations at the lo confidence level. 展开更多
关键词 of in Test of the Cosmic Transparency with the Baryon Acoustic Oscillation and type Ia Supernova Data with that is
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The X-ray Background (Deep Fields, Luminosity Functions and Type-Ⅱ Quasars)
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作者 Günther Hasinger 《天文研究与技术》 CSCD 北大核心 2003年第S1期136-146,共11页
Deep X ray surveys have shown that the cosmic X ray background (XRB) is largely due to the accretion onto supermassive black holes, integrated over the cosmic time. These surveys have resolved more than 80% of the 0.1... Deep X ray surveys have shown that the cosmic X ray background (XRB) is largely due to the accretion onto supermassive black holes, integrated over the cosmic time. These surveys have resolved more than 80% of the 0.1-10keV X ray background into discrete sources. Optical spectroscopic identifications show that the sources producing the bulk of the X ray background are a mixture of obscured (type 1) and unobscured (type 2) AGNs, as predicted by the XRB population synthesis models. A class of highly luminous type 2 AGN, so called QSO 2s, has been detected in the deepest Chandra and XMM Newton surveys. The new Chandra AGN redshift distribution peaks at much lower redshifts (z≈0.7) than that based on ROSAT data, indicating that Seyfert galaxies peak at significantly lower redshifts than QSOs. 展开更多
关键词 AGN The X-ray Background Figure Luminosity Functions and type QUASARS Deep Fields
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Perinatal Outcome and Frequency of Congenital Malformations in Pregnancy Complicated with Diabetes Type 1 and Type 2
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作者 Vjosa M. Kotori Marina Ivanišević Josip Đelmiš 《Open Journal of Obstetrics and Gynecology》 2016年第2期122-128,共7页
Objectives: The objectives of this study were to evaluate and compare perinatal outcomes and frequency of congenital malformations in pregnancy that are complicated with type 1 and type 2 diabetes. Study Design: This ... Objectives: The objectives of this study were to evaluate and compare perinatal outcomes and frequency of congenital malformations in pregnancy that are complicated with type 1 and type 2 diabetes. Study Design: This prospective study included 557 pregnant women with type 1 diabetes and 149 pregnant women with type 2 diabetes that gave birth in the Clinic for Diabetes in Pregnancy in Zagreb, from January 2000 to December 2012. Results: Women with type 2 diabetes were significantly older than women with type 1 diabetes (p < 0.003;32.8 ± 5.5 versus 29.3 ± 3.2) and they have significantly higher BMI compared to type 1 diabetes (P < 0.001;29.2 ± 6.5 versus 23.5 ± 3.8). Comparing their delivery patterns, women with type 1 diabetes were significantly more likely to give birth by caesarean section than women with type 2 diabetes (p < 0.001;466 versus 82). The offspring of women with type 1 diabetes were more likely to be delivered preterm in comparison with offspring of women with type 2 diabetes (109 versus 31). Macrosomia is recognized characteristic of pregnancies complicated by diabetes and its incidence was significantly higher in women with type 1 diabetes compared to women with type 2 diabetes (p < 0.035;174 versus 38). Neonatal malformations were higher in women with type 1 vs. type 2 diabetes (12 versus 7), but not statistically significant. Glycosylated haemoglobin (HbA1c) levels were statistically significantly higher in the first trimester (8.02% v. 6.72%), second (7.55% versus 6.27%) and third trimester (7.40% versus 6.03%) in women with type 1 and type 2 diabetes that gave birth to neonates with congenital malformations. Perinatal mortality was higher in pregnant women with type 1 diabetes than in women with type 2 diabetes (4 versus 2) but not statistically significant. Conclusion: Comparing perinatal mortality and frequency of congenital malformations in women with type 1 and type 2 diabetes, we didn’t find any important statistical differences. There is no significant difference in complication for babies of women with type 1 and type 2 diabetes, and it is likely that the most important causative factor is a high maternal blood glucose concentration. 展开更多
关键词 type 1 and type 2 Diabetes Mellitus Congenital Malformations MACROSOMIA Perinatal Mortality
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Prospective evaluation of gastric emptying using ^(13)C-octanoic breath test in relationship with the metabolic control in patients with type 1and type 2 diabetes
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作者 Bo Feng 《Chinese Medical Journal》 SCIE CAS CSCD 1999年第10期32-32,共1页
The aims were to prospectively evaluate the association of glycemic control (HbAlc) with gastric emptying in newly diagnosed Type 1 diabetic patients and subjects with longterm diabetes mellitus. Furthermore, the day ... The aims were to prospectively evaluate the association of glycemic control (HbAlc) with gastric emptying in newly diagnosed Type 1 diabetic patients and subjects with longterm diabetes mellitus. Furthermore, the day to day variability of gastric emptying for solids should be assessed. Methods 13 C octanoic breath tests were performed in 15 type 1 diabetic subjects on two separate days within one week. The influence of metabolic control on gastric emptying was prospectively examined over a mean of 8 months in 14 patients with newly diagnosed type 1 diabetes and 44 long term diabetic patients (type 1: n=31; type 2: n=13).Patients with longterm diabetes were stratified according to their HbA 1c at follow up (group 1: HbA 1c U7.5%, n=17; group 2 HbA 1c >7.5%, n=27). 13 C octanoic breath tests were sampled with an isotope selective non dispersive infrared spectrometer. The gastric emptying parameters were calculated using nonlinear regression analysis of the time course of 13 CO 2 exhalation:half emptying time (t 1/2 ) and lag phase (t lag ). Results The intraindividuell coefficient of variation was 17.8% for t 1/2 , and 28.2% for t lag . Mean t 1/2 and t lag in newly diagnosed type 1 diabetics were normal at baseline and were significantly increased at follow up. In patients with longterm diabetes, gastric emptying was unchanged during follow up. Gastric emptying was significant delayed in group 2 compared with group 1 at baseline and follow up respectively. There was a significant correlation between HbA 1c and t 1/2 , t lag at follow up. Conclusions 13 C octanoic breath test has a relatively good reproducibility in patients with type 1 diabetes. Gastric emptying times are already significantly increased after few months in newly diagnosed type 1 diabetes. There is a more pronounced delay of gastric emptying in longterm diabetic subjects with poor compared to patients with good metabolic control. 展开更多
关键词 type TEST Prospective evaluation of gastric emptying using and type 2 diabetes C-octanoic breath test in relationship with the metabolic control in patients with type 1
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Meta-analysis of lymph node metastasis in Siewert type Ⅰ and Ⅱ T1 adenocarcinomas
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作者 Hiroki Osumi Junko Fujisaki +9 位作者 Masami Omae Tomoki Shimizu Toshiyuki Yoshio Akiyoshi Ishiyama Toshiaki Hirasawa Tomohiro Tsuchida Yorimasa Yamamoto Hiroshi Kawachi Noriko Yamamoto Masahiro Igarashi 《World Journal of Meta-Analysis》 2016年第6期118-123,共6页
AIM To evaluate the incidence of lymph node metastasis (LNM) and its risk factors in patients with Siewert type Ⅰ and type Ⅱ pT1 adenocarcinomas.METHODS We enrolled 85 patients [69 men, 16 women; median age (ra... AIM To evaluate the incidence of lymph node metastasis (LNM) and its risk factors in patients with Siewert type Ⅰ and type Ⅱ pT1 adenocarcinomas.METHODS We enrolled 85 patients [69 men, 16 women; median age (range), 67 (38-84) years] who had undergone esophagectomy or proximal gastrectomy for Siewert type Ⅰ and type Ⅱ pT1 adenocarcinomas. Predictive risk factors of LNM included age, sex, location of the tumor center, confirmed Barrett’s esophageal adenocarcinoma, tumor size, macroscopic tumor type, pathology, invasion depth, presence of ulceration, and lymphovascular invasion. Multivariate logistic regression analysis was used to identify factors predicting LNM. We also evaluated the frequencies of LNM for Siewert type Ⅰ and type Ⅱ pT1 adenocarcinomas in meta-data analysis.RESULTSLNMs were found in 11 out of 85 patients (12.9%, 95%CI: 5.8-20.0). Only 1 of the 15 patients (6.6%, 95%CI: 0.0-19.2) who had a final diagnosis of pT1a adenocarcinoma had a positive LNM, whereas 10 of the 70 patients (14.2%, 95%CI: 6.0-22.4) with a final diagnosis of pT1b adenocarcinoma had positive LNM. Furthermore, only one of the 30 patients (3.3%, 95%CI: 0.0-9.7) with a tumor invasion depth within 500 μm from muscularis mucosae had positive LNM. Poor differentiation and lymphovascular invasion were independently associated with a risk of LNM. In meta-data analysis, 12 of the 355 patients (3.3%, 95%CI: 1.5-5.2) who had a final diagnosis of pT1a adenocarcinoma had a positive LNM, whereas 91 of the 438 patients (20.7%, 95%CI: 16.9-24.5) with a fnal diagnosis of pT1b adenocarcinoma had positive LNM.CONCLUSIONWe consider endoscopic submucosal dissection (ESD) is suitable for patients with Siewert type Ⅰ and type Ⅱ T1a adenocarcinomas. For patients with T1b adenocarcinoma, especially invasion depth is within 500 μm from muscularis mucosae with no other risk factor for LNM, diagnostic ESD could be a treatment option according to the overall status of patients and the presence of comorbidities. 展开更多
关键词 Siewert type and type adenocarcinomas Lymph node metastasis
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Comparison of clinical features and high-resolution esophageal motility characteristics between esophagogastric junction outflow obstruction and type Ⅱ achalasia patients
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作者 刘作静 《China Medical Abstracts(Internal Medicine)》 2016年第3期161-162,共2页
Objective To compare the clinical features and high-resolution esophageal motility-impedance characteristics among esophagogastric junction outflow obstruction(Eoo)patients,typeⅡachalasia(Ach)patients and healthy con... Objective To compare the clinical features and high-resolution esophageal motility-impedance characteristics among esophagogastric junction outflow obstruction(Eoo)patients,typeⅡachalasia(Ach)patients and healthy controls(Con),in order to explore the values of esophageal high-resolution manometry(HRM)in diagnosis and treatment of Eoo patients.Methods Patients 展开更多
关键词 Ach HRM achalasia patients Comparison of clinical features and high-resolution esophageal motility characteristics between esophagogastric junction outflow obstruction and type type high
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The relationship between chemokine ligand 1 gene polymorphism and type 2 diabetes mellitus with pulmonary tuberculosis
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作者 张金风 《China Medical Abstracts(Internal Medicine)》 2016年第3期149-,共1页
Objective To explore the relationship between chemokine(CC motif)ligand1(CCL1)gene polymorphisms(rs159291,rs159294 and rs210837)and the susceptibility of type 2 diabetes mellitus with pulmonary tuberculosis(T2DM-PTB).... Objective To explore the relationship between chemokine(CC motif)ligand1(CCL1)gene polymorphisms(rs159291,rs159294 and rs210837)and the susceptibility of type 2 diabetes mellitus with pulmonary tuberculosis(T2DM-PTB).Methods 124 T2DM cases,124T2DM-PTB cases and 130 healthy controls(NC)were collected in this case-control study.The genotypes 展开更多
关键词 PTB DM type gene The relationship between chemokine ligand 1 gene polymorphism and type 2 diabetes mellitus with pulmonary tuberculosis
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Outline of the Establishment of Automotive Regulation and Type Approval System in China
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《中国汽车(英文版)》 1995年第3期17-18,共2页
For carrying out the Industrial Policy of the Motor Industry, competent authorities concerned are working intensely in the transition from mandatory standards to technical regulations, which includes the formulation o... For carrying out the Industrial Policy of the Motor Industry, competent authorities concerned are working intensely in the transition from mandatory standards to technical regulations, which includes the formulation of auto products (including motorcycles) according to the technical regulations, any products without type approval shall not be permitred to sell, import and use. To expedite the 展开更多
关键词 Pr Outline of the Establishment of Automotive Regulation and type Approval System in China
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Early-Middle Paleozoic Andes-type Continental Margin in the Chifeng Area, Inner Mongolia: Framework, Geochronology and Geochemistry and Implications for Tectonic Evolution of the Central Asian Orogenic Belt 被引量:5
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作者 YAN Linjie XU Bei +1 位作者 ZHANG Jiaming WANG Yanyang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2020年第1期57-74,共18页
Three tectonic units have been recognized in the Chifeng area, Inner Mongolia, from north to south, including the Qiganmiao accretionary prism, Jiefangyingzi arc belt and Sidaozhangpeng molasse basin, which formed an ... Three tectonic units have been recognized in the Chifeng area, Inner Mongolia, from north to south, including the Qiganmiao accretionary prism, Jiefangyingzi arc belt and Sidaozhangpeng molasse basin, which formed an Andeantype active continent margin during the early to middle Paleozoic. The Qiganmiao accretionary prism is characterized by a mélange that consists of gabbro, two-mica quartz schist and basic volcanic rock blocks and heterogeneously deformed marble matrix. Two zircon U-Pb ages of 446.0±6.3 Ma and 1104±27 Ma have been acquired and been interpreted as the metamorphic and forming ages for the gabbro and two-mica quartz schist, respectively. The prism formed during the early to middle Paleozoic southward subduction of the Paleo Asian Ocean(PAO) and represents a suture between the North China craton(NCC) and Central Asian Orogenic Belt(CAOB). The Jiefangyingzi arc belt consists of pluton complex and volcanic rocks of the Xibiehe and Badangshan Formations, and Geochronology analysis indicates that the development of it can be divided into two stages. The first stage is represented by the Xibiehe Formation volcanic rocks, which belong to the subalkaline series, enriched LREE and LILE and depleted HFSE, with negative Eu anomalies, and plot in the volcanic arc field in discrimination diagrams. These characters indicate that the Xibiehe Formation results from to the continental arc magmatic activity related to the subduction of the PAO during 400–420 Ma. Magmatism of the second stage in 380–390 Ma consists of the Badangshan Formation volcanic rocks. Geochemistry analysis reveals that rhyolite, basaltic andesite and basalt of the Badangshan Formation were developed in continental margin arc setting. Moreover, the basaltic andesite and basalt display positive Sr anomalies, and the basalt have very low Nb/La values, suggesting that fluid is involved in magma evolution and the basalts were contaminated by continental crust. The sequence of Sidaozhangpeng molasse basin is characterized by proximity, coarseness and large thickness, similar to the proximity molasses basin. According to our field investigation, geochronological and geochemical data, combined with previous research in this area, a tectonic evolutionary model for Andes-type active continental margin of the CAOB has been proposed, including a development of the subduction-free PAO before 446 Ma, a subduction of the PAO and arc-related magmatism during 446–380 Ma, and formation of a molasse basin during 380–360 Ma. 展开更多
关键词 Chifeng area andes-type continental margin early-middle PALEOZOIC tectonic evolution Central Asian OROGENIC Belt
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Identification and Evaluation of Low Resistivity Pay Zones by Well Logs and the Petrophysical Research in China 被引量:3
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作者 Mao Zhiqiang Kuang Lichun +3 位作者 Xiao Chengwen Li Guoxin Zhou Cancan Ouyang Jian 《Petroleum Science》 SCIE CAS CSCD 2007年第1期41-48,共8页
This paper presents an overview of petrophysical research and exploration achievements of low resistivity pay (LRP) zone by well logs in China. It includes geological characteristics and characteristics of well log ... This paper presents an overview of petrophysical research and exploration achievements of low resistivity pay (LRP) zone by well logs in China. It includes geological characteristics and characteristics of well log response of the low resistivity pay zones discovered and evaluated in recent years, as well as the problems in recognizing and evaluating low resistivity pay zones by well logs. The research areas mainly include the Neogene formations in the Bohai Bay Basin, the Triassic formations in the northern Tarim Basin and the Cretaceous formations in the Junggar Basin, The petrophysical research concerning recognition and evaluation of the low resistivity pays, based on their genetic types, is introduced in this paper. 展开更多
关键词 Low-resistivity pay zone in China origin and type petrophysical research identification and evaluation by well logs
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Inscuteable maintains type I neuroblast lineage identity via Numb/Notch signaling in the Drosophila larval brain 被引量:1
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作者 Huanping An Wanzhong Ge +1 位作者 Yongmei Xi Xiaohang Yang 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2017年第3期151-162,共12页
In the Drosophila larval brain, type I and type Ⅱ neuroblasts(NBs) undergo a series of asymmetric divisions which give rise to distinct progeny lineages. The intermediate neural progenitors(INPs) exist only in ty... In the Drosophila larval brain, type I and type Ⅱ neuroblasts(NBs) undergo a series of asymmetric divisions which give rise to distinct progeny lineages. The intermediate neural progenitors(INPs) exist only in type Ⅱ NB lineages. In this study, we reveal a novel function of Inscuteable(Insc) that acts to maintain type I NB lineage identity. In insc type I NB clones of mosaic analyses with a repressible cell marker(MARCM), the formation of extra Deadpan(Dpn)tNB-like and GMC-like cells is observed. The lack of Insc leads to the defective localization and segregation of Numb during asymmetric cell division. By the end of cytokinesis, this results in insufficient Numb in ganglion mother cells(GMCs). The formation of extra Deadpan(Dpn)tcells in insc clones is prevented by the attenuation of Notch activity. This suggests that Insc functions through the Numb/Notch signaling pathway. We also show that in the absence of Insc in type I NB lineages, the cellular identity of GMCs is altered where they adopt an INP-like cell fate as indicated by the initiation of Dpn expression accompanied by a transient presence of Earmuff(Erm).These INP-like cells have the capacity to divide multiple times. We conclude that Insc is necessary for the maintenance of type I NB lineage identity. Genetic manipulations to eliminate most type I NBs with overproliferating type Ⅱ NBs in the larval brain lead to altered circadian rhythms and defective phototaxis in adult flies. This indicates that the homeogenesis of NB lineages is important for the adult's brain function. 展开更多
关键词 Drosophila larval brain neuroblasts(NBs) Inscuteable(Insc) NB lineage maintenance type I and type NBs Numb/Notch signaling
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Calculation and Selection of Feed Mechanism of Truss Manipulator
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作者 DONG Hongbo WANG Jianjun +1 位作者 SU Hongzhi ZHAO Mingwei 《外文科技期刊数据库(文摘版)工程技术》 2021年第9期1285-1288,共6页
This paper mainly introduces the calculation and selection process of the feed mechanism of the truss manipulator. According to the handling load, beat and handling accuracy required by the production line, the three ... This paper mainly introduces the calculation and selection process of the feed mechanism of the truss manipulator. According to the handling load, beat and handling accuracy required by the production line, the three shaft transmission mechanism of the truss is calculated and selected. 展开更多
关键词 design and type selection gear rack REDUCER
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丹东花岗岩的地球化学特征及其成因 被引量:37
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作者 李三忠 郝德峰 +3 位作者 赵国春 孙敏 韩宗珠 郭晓玉 《岩石学报》 SCIE EI CAS CSCD 北大核心 2004年第6期1417-1423,共7页
新的SHRIMP定年结果表明,原先划归于古元古代的丹东花岗杂岩现在被确定为中生代岩体.其岩浆型环锆石带的年龄代表结晶年龄,为167~157 Ma;但是这些锆石的核部年龄主体为古元古代.本文侧重探讨丹东花岗岩体的岩石学和地球化学特征,论证... 新的SHRIMP定年结果表明,原先划归于古元古代的丹东花岗杂岩现在被确定为中生代岩体.其岩浆型环锆石带的年龄代表结晶年龄,为167~157 Ma;但是这些锆石的核部年龄主体为古元古代.本文侧重探讨丹东花岗岩体的岩石学和地球化学特征,论证其起源和产生的构造背景.研究结果表明,丹东花岗岩体具铕异常(Eu/Eu*=0.59~1.41),轻重稀土分异明显,其微量元素特征与安第斯型构造背景下的花岗岩特征一致,其tDM和εNd(t)变化范围分别为1.93~2.30 Ga和-17.95~-21.32.εNd(t)-t图解显示丹东花岗岩的源岩以古元古代中酸性壳源岩石为主.构造环境环境判别结果表明其形成于大陆边缘岩浆弧.结合中生代丹东地区所处的大地构造背景,本文认为丹东花岗岩体的起源和侵位与古太平洋板块向欧亚板块的俯冲有关. 展开更多
关键词 丹东花岗岩 ND同位素 安第斯型 辽东半岛 中生代
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华北北部二叠纪陆壳演化 被引量:45
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作者 邵济安 何国琦 唐克东 《岩石学报》 SCIE EI CAS CSCD 北大核心 2015年第1期47-55,共9页
目前围绕华北北部(包括华北克拉通北缘和北邻的兴蒙造山带)的二叠纪的构造背景存在着不同的认识。其中一种影响较大的观点是古亚洲洋的演化持续到二叠纪末-三叠纪初,由于大洋板块向华北克拉通之下的俯冲,导致克拉通北缘成为"安第斯... 目前围绕华北北部(包括华北克拉通北缘和北邻的兴蒙造山带)的二叠纪的构造背景存在着不同的认识。其中一种影响较大的观点是古亚洲洋的演化持续到二叠纪末-三叠纪初,由于大洋板块向华北克拉通之下的俯冲,导致克拉通北缘成为"安第斯型"大陆边缘。活动陆缘有从早期(C2)的板块俯冲-汇聚向晚期(P2-T1-2)板块拆离-陆缘伸展演变的趋势,论证多偏于岩浆作用。本文将从沉积建造、变形、变质、岩浆活动以及区域构造背景等角度对此观点进行讨论,本文将研究区晚古生代陆壳演化划分为三个阶段:(1)法门阶之前的中泥盆世是兴蒙造山带的主造山阶段;(2)晚泥盆-早石炭世进入后碰撞阶段;(3)晚石炭世-早二叠世兴蒙造山带的年轻陆壳在伸展背景下,上叠的新生性裂陷槽构造而非大洋板块控制了同期的沉积作用和岩浆活动。这三阶段的地质事件在华北克拉通北缘都有相应的表现。研究区深成岩同位素年龄显示了中-晚泥盆世、早二叠世和晚二叠世三个峰值。为了揭示岩浆的形成机制,本文重点对研究区早二叠世(280Ma)和晚二叠世(260Ma)深成岩的岩石组合和Sr-Nd同位素特征进行对比研究。R1-R2图显示本区二叠纪深成岩组合与以英云闪长岩和花岗闪长岩为主的安第斯型造山带不同。早二叠世深成岩具双峰特征,Sr-Nd同位素显示早二叠世深成岩与EMI地幔源区有更密切联系。受到前人对高寺台原始岩浆研究的启发,进一步认识到华北克拉通北缘在早二叠世时存在板内OIB岩浆沿着岩石圈断裂的上涌的过程。相比之下,晚二叠世深成岩多为正长花岗岩和二长花岗岩,岩石碱性程度提高,中酸性岩石具高碱、高钾的特征。Sr-Nd同位素显示岩浆源区有向EMII演变的趋势,中-上部地壳熔融物质增多,暗示热活动带的上升。总之,从岩浆形成机制、岩浆源区演变的趋势和岩浆时空演化等诸多证据都表明:二叠纪深成岩的形成更多地与板内自身热演化有关,与安第斯型造山带有明显区别。兴蒙造山带属于中亚造山带的一部分,因此可以从更大的构造背景对它加以考察。中亚造山带存在8条晚古生代和中生代的过碱性-碱性长石花岗岩带,它们共同都伴有双峰式火山岩。构造岩浆岩带横贯数千千米,北东走向的构造带显示了新的构造格局,高εNd(t)和低εSr(t)的同位素特征,反映了伸展背景下裂谷带的反复多次活动。总体上,中亚造山带作为增生的年轻陆壳,与华北克拉通及塔里木地块等一起从早二叠世开始,进入了新阶段的演化。从大陆岩石圈形成过程的克拉通化角度看,中亚造山带晚泥盆世-早石炭世是碰撞后的第一阶段的克拉通化,晚石炭-早二叠世进入克拉通化的第二阶段,大规模的新生的带状伸展构造出现,标志着深部作用的重要性越来越明显。 展开更多
关键词 华北克拉通北缘 陆壳演化 安第斯型造山带 二叠纪深成岩 克拉通化
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南美安第斯地区成矿区带划分探讨 被引量:22
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作者 卢民杰 朱小三 郭维民 《矿床地质》 CAS CSCD 北大核心 2016年第5期1073-1083,共11页
南美安第斯成矿带是世界上最著名的Cu、Au、多金属巨型成矿带,产有一系列大型-超大型Cu、Au、多金属矿床,是目前世界上最重要的找矿投资热点地区之一。文章在系统收集资料和综合研究的基础上,依据安第斯成矿带的基底组成、构造_岩浆演... 南美安第斯成矿带是世界上最著名的Cu、Au、多金属巨型成矿带,产有一系列大型-超大型Cu、Au、多金属矿床,是目前世界上最重要的找矿投资热点地区之一。文章在系统收集资料和综合研究的基础上,依据安第斯成矿带的基底组成、构造_岩浆演化、板块俯冲形式、成矿作用以及主要成矿类型的差异,将安第斯地区自北而南划分为3个Ⅱ级成矿省和14个Ⅲ级成矿带,并对各成矿区带的地质与成矿特征进行了概要阐述,为安第斯地区区域成矿规律研究提供了基础,也为中国企业在该地区的矿产勘查、开发投资提供了指导信息。 展开更多
关键词 地质学 构造_岩浆演化 成矿区带划分 成矿类型 安第斯
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有关中国东部中、新生代活动大陆边缘构造—岩浆作用演化问题沉思录 被引量:2
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作者 胡受奚 《地球科学(中国地质大学学报)》 EI CSCD 北大核心 1992年第S1期40-46,共7页
文章提出和讨论许多有关中、新生代各个时期,如印支期(T—J;,250—185Ma)、燕山早期八一L,185~NOM幻、燕山中期(民,10~tX)MtX)M劝、燕山晚期(氏,!m~刀M的和喜马拉雅期o----m一Q 7()M~现在)的构造一岩浆作用问题,强调不同类型岩浆... 文章提出和讨论许多有关中、新生代各个时期,如印支期(T—J;,250—185Ma)、燕山早期八一L,185~NOM幻、燕山中期(民,10~tX)MtX)M劝、燕山晚期(氏,!m~刀M的和喜马拉雅期o----m一Q 7()M~现在)的构造一岩浆作用问题,强调不同类型岩浆岩如改造型花岗岩、同熔型花岗岩类、碱性花岗岩、钙碱性安山一流纹岩系、碱性火山岩以及不同类型的玄武岩与中国东部活动大陆边缘演化之间的重要的时间和空间变化的联系.经长期考虑,认为燕山晚期中国东部是沟一弧体系(安第斯型)向沟一弧一边缘海体系(西太平洋式)转化的过渡时期.与A型和B型俯冲有联系的火山作用在总体上的减弱、拉伸红盆在整个中国东部大陆的广泛分布以及沿海岸延伸长达ZMm左右的碱性花岗岩带的形成是这一过渡时期的良好标志.在新生代,钙碱性安山一流纹岩系、改造型花岗岩和同熔型花岗岩的消亡,碱性、高铝质玄武岩在大陆边缘的广泛分布,以及拉伸盆地发生加深和加宽;边缘海随着时间不断加深和加宽,并导致大洋玄武岩的发育;与B型俯冲有联系的钙碱性火山岩和同熔型花岗岩类迁移到岛弧地带. 展开更多
关键词 改造型花岗岩 同熔型花岗岩类 碱性花岗岩 A型俯冲 B型俯冲 安第斯型活动大陆边缘 西太平洋型活动大陆边缘
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南美西北部典型含油气盆地构造特征 被引量:17
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作者 杨福忠 魏春光 +2 位作者 尹继全 张春雷 谢寅符 《大地构造与成矿学》 EI CAS CSCD 北大核心 2009年第2期230-235,共6页
依据盆地处于造山弧的位置不同,将南美西北部盆地群分为弧前盆地、弧内盆地和弧后盆地三类。同一动力学背景下在不同构造部位形成了三类盆地不同的构造特征。弧前盆地具有地垒-地堑式裂陷盆地特点,发育断块油气藏,是安第斯俯冲增生带之... 依据盆地处于造山弧的位置不同,将南美西北部盆地群分为弧前盆地、弧内盆地和弧后盆地三类。同一动力学背景下在不同构造部位形成了三类盆地不同的构造特征。弧前盆地具有地垒-地堑式裂陷盆地特点,发育断块油气藏,是安第斯俯冲增生带之上的近东西向张性盆地;弧内盆地位于强烈挤压隆升的造山带之内,是造山带内局部变形相对较弱的地区,发育叠瓦逆冲断层、双重构造和冲起构造;弧后盆地以逆断层反转构造和低幅度背斜构造为主,断裂系统具有走滑性质,是斜向弱挤压环境下的产物,构造平面上具东西向分带的特点,圈闭类型主要是低幅度背斜和岩性圈闭。 展开更多
关键词 含油气盆地 构造特征 圈闭类型 安第斯俯冲带 南美
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On the Growth Properties of Solutions for a Generalized Bi-Axially Symmetric Schrödinger Equation
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作者 Devendra KUMAR Payal BISHNOI Mohammed HARFAOUI 《Journal of Mathematical Research with Applications》 CSCD 2017年第2期214-222,共9页
In this paper, we have considered the generalized bi-axially symmetric SchrSdinger equation ■2φ/■x2 + ■2φ/■y2+2v/x ■φ/■x+2μ/y ■φ/■y+{K2-V(r)}φ=0 ,where μ, v ≥ 0, and rV(r) is an entire function... In this paper, we have considered the generalized bi-axially symmetric SchrSdinger equation ■2φ/■x2 + ■2φ/■y2+2v/x ■φ/■x+2μ/y ■φ/■y+{K2-V(r)}φ=0 ,where μ, v ≥ 0, and rV(r) is an entire function of r=+(s2+y2)1/2 corresponding to a scattering potential V(r). Growth paramet ers of entire function solutions in terms of their expansion coefficients, which are analogous to the formulas for order and type occurring in classical function theory, have been obtained. Our results are applicable for the scattering of particles in quantum mechanics. 展开更多
关键词 Schro?dinger equation scattering potential Jacobi polynomials order and type
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