期刊文献+
共找到6,362篇文章
< 1 2 250 >
每页显示 20 50 100
Step-by-step anatomical photovaporization of the prostate using 180-W XPS greenlight laser:optimizing functional outcomes through energy modulation
1
作者 Fabrizio Di Maida Francesca Oriti +11 位作者 Antonio Andrea Grosso Francesco Sessa Daniele Paganelli Vincenzo Salamone Sara Costagli Francesca Solazzi Luca Lambertini Matteo Salvi Michele Di Dio Andrea Mari Rino Oriti Andrea Minervini 《The Canadian Journal of Urology》 2025年第4期283-292,共10页
Background:The surgical management of patients with benign prostatic hyperplasia(BPH)has considerably evolved through recent years.Nonetheless,benefits and harms of several laser procedures are still to be determined.... Background:The surgical management of patients with benign prostatic hyperplasia(BPH)has considerably evolved through recent years.Nonetheless,benefits and harms of several laser procedures are still to be determined.The study aimed to report perioperative and early functional results of patients treated with anatomical photo vaporization of the prostate(aPVP).Methods:Data from consecutive patients treated with aPVP by using a 180-W XPS GreenLight laser were prospectively collected in a single tertiary center between 2020 and 2023.The surgical procedure was divided into a modular step-by-step fashion.Patients were asked to complete self-administered questionnaires at baseline and during follow-up visits.Results:Overall,176 consecutive patients were enrolled.Median age was 65[interquartile range(IQR)63–72]years.The baseline median prostate volume was 61.2(IQR 52.5–71.0)mL,and the median max flow rate(Qmax)was 9.3(IQR 7.8–11.5)mL/s.Median preoperative International Prostate Symptom Score(IPSS)was 25(IQR 22–29).Overall,the median operative time was 42(IQR 31–47)minutes with a median energy/mL of tissue delivered of 2447 kJ/mL.At 3 month-evaluation,significant improvements were observed,with a median Qmax of 28(IQR:24–32)mL/s and a median IPSS reduction of 15(IQR:11–18)points.A strong inverse correlation was identified between energy delivery during initial procedural steps and the severity of postoperative storage symptoms(all p<0.05),underscoring the importance of precise energy modulation.Multivariate analysis identified increased prostate volume(odds ratio[OR]:1.02;95%confidence interval[CI]1.01–1.11;p=0.001)and higher prostate width-to-length ratio(OR:1.28;95%CI 1.04–1.78;p=0.03)as independent predictors of increased energy requirements.Conclusions:aPVP with 180-W XPS GreenLight laser is a safe and effective technique showing worthy early functional results.The limitation of the energy delivered in some key phases of the procedure may be associated with a significant reduction in postoperative irritative symptoms.The shape and dimensions of the prostate also play a critical role in determining the total energy required for complete adenoma removal. 展开更多
关键词 anatomical green LASER VAPORIZATION PROSTATE
暂未订购
Analysis and optimization of microchannel array precision grinding processes with micro-structured micro-grinding tool
2
作者 Jianfei JIA Qinghe ZHANG +7 位作者 Wei YANG Honghui YAO Guicheng WU Huan ZHAO Jianhui ZHU Kenan LI Bing GUO Jun QIN 《Chinese Journal of Aeronautics》 2025年第7期669-683,共15页
Micro-grinding has been widely used in aerospace and other industry.However,the small diameter of the micro-grinding tool has limited its machining performance and efficiency.In order to solve the above problems,micro... Micro-grinding has been widely used in aerospace and other industry.However,the small diameter of the micro-grinding tool has limited its machining performance and efficiency.In order to solve the above problems,micro-structure has been applied on the micro-grinding tool.A morphology modeling has been established in this study to characterize the surface of microstructured micro-grinding tool,and the grinding performance of micro-structured micro-grinding tool has been analyzed through undeformed chip thickness,abrasive edge width,and effective distance between abrasives.Then deviation analysis,path optimization and parameter optimization of microchannel array precision grinding have been finished to improve processing quality and efficiency,and the deflection angle has the most obvious effects on the rectangular slot depth,micro-structured micro-grinding tool could reduce 10%surface roughness and 20%grinding force compared to original micro-grinding tool.Finally,the microchannel array has been machined with a size deviation of 2μm and surface roughness of 0.2μm. 展开更多
关键词 GRINDING Precision grinding Microchannel array micro-structure Micro-grinding tool
原文传递
Integrated single-cell transcriptomic map of pig kidney cells across various periods and anatomical sites
3
作者 Tian-Xiong Yao Na Li Lu-Sheng Huang 《Zoological Research》 2025年第2期469-482,共14页
The kidney is essential for maintaining fluid,electrolyte,and metabolite homeostasis,and for regulating blood pressure.The pig serves as a valuable biomedical model for human renal physiology,offering insights across ... The kidney is essential for maintaining fluid,electrolyte,and metabolite homeostasis,and for regulating blood pressure.The pig serves as a valuable biomedical model for human renal physiology,offering insights across different physiological states.In this study,single-cell RNA sequencing was used to profile 138469 cells from 12 pig kidney samples collected during the embryonic(E),fattening(F),and pregnancy(P)periods,identifying 29 cell types.Proximal tubule(PT)cells exhibited elevated expression of metabolism-related transcription factors(TFs),including GPD1,ACAA1,and AGMAT,with validation across multiple individuals,periods,and species.Fluorescence homologous double-labeling of paraffin sections further confirmed the expression of ACAA1 and AGMAT in PT cells.Comparative analysis of pig and human kidneys revealed a high degree of similarity among corresponding cell types.Analysis of cell-type heterogeneity highlighted the diversity of thick ascending limb(TAL)cells,identifying a TAL subpopulation related to immune function.Additionally,the functional heterogeneity of kidney-resident macrophages(KRM)was explored across different anatomical sites.In the renal medulla,KRM were implicated in phagocytosis and leukocyte activation,whereas in the renal pelvis,they functioned as ligands,recruiting neutrophils with bactericidal activity to the renal pelvis to combat urinary tract infections. 展开更多
关键词 PIG Kidney Single-cell RNA sequencing PERIODS anatomical sites
在线阅读 下载PDF
Elevational variation in anatomical traits of the first-order roots and their adaptation mechanisms
4
作者 Xue Wang Xinrui Liu +9 位作者 Shuang Chen Jiang Zhu Yanqi Yuan Rong Zhu Kaixi Chen Xue Yang Xiaochun Wang Weiyi Mo Ruili Wang Shuoxin Zhang 《Plant Diversity》 2025年第2期291-299,共9页
Root anatomical traits play an important role in understanding the link between root physiological function and ecological process. To determine how plants change root anatomical traits to adapt to distinct environmen... Root anatomical traits play an important role in understanding the link between root physiological function and ecological process. To determine how plants change root anatomical traits to adapt to distinct environments, we measured four key root anatomical traits-stele diameter(SD), cortex thickness(CT), root diameter(RD), and the stele to root diameter ratio(SDRD)-of first-order roots of 82species collected from different vegetation zones along a 2000 m altitudinal gradient on the northern slope of Taibai Mountain. Compared with other altitudes, plants located in temperate birch and fir forests had thinner SD, CT, RD, and SDRD. We found that elevational variation in root anatomical traits could largely be explained by phylogenetic taxonomy(clade). In addition, changes in SD were driven by soil bulk density, whereas variations in CT and RD were influenced by soil available nitrogen. When phylogenetic factors were removed from our analysis, allometric relationships between RD and root anatomical traits(SD and CT) were observed across different altitudes. Our study reveals the influence of phylogeny and environment on the elevational variation in root anatomical traits and further supports the allometric relationship between root anatomical traits(SD and CT) and RD. These findings enhance our understanding of the evolutionary and adaptive mechanisms of root anatomical structures, providing a basis for predicting how root anatomical traits respond to global changes. 展开更多
关键词 Allometric relationship ALTITUDE PHYLOGENY Root anatomical traits Stressful environment
在线阅读 下载PDF
Micro-structure evolution, precipitation behavior and strengthening mechanism of Ni-Cr-Mo system steel fabricated via laser powder bed fusion and subsequent quenching control
5
作者 Qing WANG Deyin KONG +2 位作者 Shihui ZHOU Xingran LI Zhihui ZHANG 《Chinese Journal of Aeronautics》 2025年第3期560-592,共33页
High-performance 24CrNiMo steel was fabricated using Laser Powder Bed Fusion (LPBF). Subsequent quenching treatment was applied and the influence of quenching temperatures on micro-structure evolution and properties w... High-performance 24CrNiMo steel was fabricated using Laser Powder Bed Fusion (LPBF). Subsequent quenching treatment was applied and the influence of quenching temperatures on micro-structure evolution and properties was systematically characterised and analysed. The micro-structure of the as-built steel consisted of two parts. The first part comprised martensite with twins combined with ω-Fe nano-particles, and the second part consisted of lower bainite in the molten pool, as well as upper bainite, granular bainite and tempered martensite in the heat-affected zone. With the quenching temperatures varying from 800℃ to 950℃, the micro-structure gradually transformed from acicular ferrite + martensite to tempered martensite +θ-Fe3C carbides, and the grain size exhibited noticeable growth. Moreover, quenching treatments could eliminate the anisotropy and inhomogeneity of the micro-structure. The rod-shaped nanosized η-Fe2C and θ-Fe3C precipitates were clearly observed, which were converted from ω-Fe and distributed at multiple angles in the lath. The size and number of nano-precipitates, triggered by the high self-tempering degree of martensite, gradually increased. The relationships among grain size, the twins, dislocation density and nano-precipitation and the dramatically improved performance of quenched samples were analysed using strengthening mechanisms. After quenching at 850℃, the as-built 24CrNiMo steel attained ultra-high mechanical properties including hardness, Ultimate Tensile Strength (UTS), Elongation (El) and impact energy with values of 480.9 HV_(1), 1611.4 MPa, 9.8% and 42.8 J, respectively. Meanwhile, both the wear and thermal fatigue resistance increased by approximately 40%. This study demonstrated that LPBF-fabricated 24CrNiMo steel, with matching good performances, can be achieved using a subsequent one-step quenching process. 展开更多
关键词 Laser powder bed fusion 24CrNIMo steel Quenching control micro-structure evolution Precipitate Comprehensive properties Strengthening mechanisms
原文传递
Navigating anatomical complexity in laparoscopic sigmoid cancer surgery:A three-dimension reconstruction protocol for intraoperative safety and efficiency
6
作者 Zong-Xian Zhao Run-Dong Yao +3 位作者 Zong-Ju Hu Chao-Qian Chen Shu Zhu Yuan Yao 《World Journal of Gastrointestinal Surgery》 2025年第8期350-361,共12页
BACKGROUND Sigmoid colon cancer faces challenges due to anatomical diversity,including variable inferior mesenteric artery(IMA)branching and tumor localization complexities,which increase intraoperative risks.AIM To c... BACKGROUND Sigmoid colon cancer faces challenges due to anatomical diversity,including variable inferior mesenteric artery(IMA)branching and tumor localization complexities,which increase intraoperative risks.AIM To comprehensively evaluate the impact of three-dimensional(3D)visualization technology on enhancing surgical precision and safety,as well as optimizing perioperative outcomes in laparoscopic sigmoid cancer resection.METHODS A prospective cohort of 106 patients(January 2023 to December 2024)undergoing laparoscopic sigmoid cancer resection was divided into the 3D(n=55)group and the control(n=51)group.The 3D group underwent preoperative enhanced computed tomography reconstruction(3D Slicer 5.2.2&Mimics 19.0).3D reconstruction visualization navigation intraoperatively guided the following key steps:Tumor location,Toldt’s space dissection,IMA ligation level selection,regional lymph node dissection,and marginal artery preservation.Outcomes included operative parameters,lymph node yield,and recovery metrics.RESULTS The 3D group demonstrated a significantly shorter operative time(172.91±20.69 minutes vs 190.29±32.29 minutes;P=0.002),reduced blood loss(31.5±11.8 mL vs 44.1±23.4 mL,P=0.001),earlier postoperative flatus(2.23±0.54 days vs 2.53±0.61 days;P=0.013),shorter hospital length of stay(13.47±1.74 days vs 16.20±7.71 days;P=0.013),shorter postoperative length of stay(8.6±2.6 days vs 10.5±4.9 days;P=0.014),and earlier postoperative exhaust time(2.23±0.54 days vs 2.53±0.61 days;P=0.013).Furthermore,the 3D group exhibited a higher mean number of lymph nodes harvested(16.91±5.74 vs 14.45±5.66;P=0.030).CONCLUSION The 3D visualization technology effectively addresses sigmoid colon anatomical complexity through surgical navigation,improving procedural safety and efficiency. 展开更多
关键词 Three-dimension reconstruction Sigmoid colon cancer Visualization Inferior mesenteric artery anatomical complexity Intraoperative safety
暂未订购
Comparative evaluation of diaphragmatic excursion in ICU patients:ultrasonography assessment via the conventional M-mode versus the anatomical M-mode
7
作者 Issac Cheong Francisco Marcelo Tamagnone 《World Journal of Emergency Medicine》 2025年第5期488-490,共3页
Diaphragmatic function is central to respiration,and its evaluation is critical in intensive care unit(ICU)settings.Ultrasonography is a reliable bedside tool to assess diaphragmatic excursion(DE).[1,2]The conventiona... Diaphragmatic function is central to respiration,and its evaluation is critical in intensive care unit(ICU)settings.Ultrasonography is a reliable bedside tool to assess diaphragmatic excursion(DE).[1,2]The conventional M-mode(MM)offers high-resolution imaging but requires precise alignment,which can be diffi cult in ICU patients.[3-5]Anatomical M-mode(AMM)allows flexible line adjustment,enabling accurate DE measurements despite poor acoustic windows.[6]However,comparative data between MM and AMM are limited.This retrospective study evaluated the concordance between MM and AMM for assessing right DE. 展开更多
关键词 intensive care unit conventional M mode anatomical M mode diaphragmatic excursion ULTRASONOGRAPHY precise alignmentwhich
暂未订购
Navigating the challenges of laparoscopic anatomical SVIII resection:A step forward in hepatobiliary surgery
8
作者 Jin-Wei Zhang 《World Journal of Gastrointestinal Surgery》 2025年第2期308-311,共4页
This article comments on the study by Peng et al,published in the World Journal of Gastrointestinal Surgery,representing a notable advancement in hepatobiliary surgery.This article examines laparoscopic anatomical seg... This article comments on the study by Peng et al,published in the World Journal of Gastrointestinal Surgery,representing a notable advancement in hepatobiliary surgery.This article examines laparoscopic anatomical segment VIII resection,a challenging procedure due to the complex liver anatomy and difficulty in accessing deep-seated lesions.Peng and colleagues’experience with caudal and cranial approaches in 34 patients underscores the feasibility of these techniques while sparking debates about the optimal approach.Their study’s strengths lie in technique standardization and comprehensive analysis,although its limitations highlight the need for further research.As minimally invasive liver surgery progresses,larger,prospective trials and integration of advanced technologies are essential for establishing best practices. 展开更多
关键词 Laparoscopic liver resection anatomical segmentectomy Segment VIII Middle hepatic fissure approach Surgical techniques
暂未订购
A gradient nano/micro-structured surface layer on copper induced by severe plasticity roller burnishing 被引量:7
9
作者 赵婧 夏伟 +1 位作者 李宁 李风雷 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第2期441-448,共8页
In order to investigate a gradient nano/micro-structured surface layer on pure copper produced by severe plasticity roller burnishing (SPRB) and grain refinement mechanism, the microstructure characteristics and mat... In order to investigate a gradient nano/micro-structured surface layer on pure copper produced by severe plasticity roller burnishing (SPRB) and grain refinement mechanism, the microstructure characteristics and material properties of sample at various depths from the topmost surface were investigated by SEM, TEM, XRD, OM etc. The experimental results show that the gradient nano/micro-structure was introduced into the surface layer of over 100μm in thickness. The remarkable increase in hardness near the topmost surface was mainly attributed to the reduced grain size. The equiaxed nano-sized grains were in random orientation and the most of their boundaries were low-angle grain boundaries (LAGBs). The coarse grains are refined into the few micro-sized grains by dislocation activities;deformation twinning was found to be the primary form for the formation of submicron grains;the formation of nanostructure was dominated by dislocation activities accompanied with rotation of grains in local region. 展开更多
关键词 BURNISHING pure copper gradient nano/micro-structure surface nanocrystallization
在线阅读 下载PDF
Effect of TYLCV Infection on Leaf Anatomical Structure and Protective Enzyme System of Tomato 被引量:7
10
作者 张永平 张辉 +1 位作者 朱龙英 朱为民 《Agricultural Science & Technology》 CAS 2009年第4期150-153,共4页
[Objective] The aim was to study the effect of tomato yellow leaf curl virus (TYLCV) infection on leaf anatomical structure and protective enzyme system of tomato. [Method] The anatomical structure of infected and h... [Objective] The aim was to study the effect of tomato yellow leaf curl virus (TYLCV) infection on leaf anatomical structure and protective enzyme system of tomato. [Method] The anatomical structure of infected and healthy leaves of tomato were observed and compared by using paraffin section method. The activity changes of SOD, POD and CAT in the infected leaves of tomato were determined. [ Result] The results revealed that there were some differences in anatomical structure between healthy and infected leaves. Some cells of infected leaves were damaged so that the leaves curled and became yellow, which affected the normal function of organs. Compared with control, enzyme activities in the tomato plants infected by TYLCV were enhanced at the early periods and higher than that in control, then started to decline at the middle and late periods but lower than that in control.[ Conclusion] After infection by TYLCV, the leaf anatomical structure of tomato was changed greatly and the protective enzyme system was damaged severely, and affected the normal physJological metabolic functions of tissues and organs in tomato in further. 展开更多
关键词 TYLCV INFECTION anatomical structure Protective enzyme system
在线阅读 下载PDF
Research Progress on Leaf Anatomical Structures of Plants Under Drought Stress 被引量:9
11
作者 刘球 李志辉 吴际友 《Agricultural Science & Technology》 CAS 2016年第1期4-7,14,共4页
Plants usually suffer drought stress during their growth process. As the photosynthetic activity center of plants, the leaf is the most sensitive organ under drought stress. In order to support the research on drought... Plants usually suffer drought stress during their growth process. As the photosynthetic activity center of plants, the leaf is the most sensitive organ under drought stress. In order to support the research on drought resistance of higher plants, this study reviewed the adaptation response and damage performance of epidermal structure, palisade tissue and spongy tissue, thickness, veins and stomata of plant leaves under drought stress. 展开更多
关键词 Leaf anatomical structure Drought stress PLANT
在线阅读 下载PDF
Effects of Salt Stress on Anatomical Structure of Leaves of Malus sieversii and Malus robusta 被引量:2
12
作者 马兰 吴玉霞 何天明 《Agricultural Science & Technology》 CAS 2016年第8期1777-1779,1785,共4页
[Objective] This study was conducted to compare leaf anatomical structure of Malus sieversii and M. robusta under different salt concentration levels to determine their tolerance to salt and thus to provide rootstock ... [Objective] This study was conducted to compare leaf anatomical structure of Malus sieversii and M. robusta under different salt concentration levels to determine their tolerance to salt and thus to provide rootstock materials for apple production in salinized soil in Southern Xinjiang. [Method] The experiment was conducted with M. sieversii and M. robusta as test materials. Salt stress was simulated using 8 g/L of NaCI solution, and Hoagland nutrient solution was used instead of NaCI solution as control group (CK). Samples were collected on the 20^th d of treatment, sliced through paraffin processing. The prepared paraffin sections of M. sieversii and M. robusta were then observed under a light microscope for anatomical structures of leaf, upper epidermis, lower epidermis, palisade tissue and spongy tissue. [Result] Compared with the control, the leaf, upper epidermis, lower epidermis and spongy tissue of M. sieversii and M. robusta under salt stress were thickened at different degrees, while the thickness of the palisade tissue was decreased. Moreover, high salt concentration caused severer damage to the cell structure of M. sieversii than to that of M. robusta, as M. robusta cells maintained better structural integrity. [Conclusion] M. robusta has higher adaptability to salt stress than M. sieversii. 展开更多
关键词 NaCl stress M. sieversii M. robusta Leaf anatomical structure
在线阅读 下载PDF
Anatomical and chemical characteristics associated with lodging resistance in wheat 被引量:53
13
作者 Eryan Kong Dongcheng Liu +7 位作者 Xiaoli Guo Wenlong Yang Jiazhu Sun Xin Li Kehui Zhan Dangqun Cui Jinxing Lin Aimin Zhang 《The Crop Journal》 SCIE CAS 2013年第1期43-49,共7页
Anatomical and chemical characteristics of stems affect lodging in wheat(Triticum aestivum L.) cultivars. Traits associated with lodging resistance, such as plant height, stem strength, culm wall thickness, pith diame... Anatomical and chemical characteristics of stems affect lodging in wheat(Triticum aestivum L.) cultivars. Traits associated with lodging resistance, such as plant height, stem strength, culm wall thickness, pith diameter, and stem diameter, were extensively investigated in earlier studies. However, the solid stem trait was rarely considered. In this study, we measured a range of anatomical and chemical characteristics on solid and hollow stemmed wheat cultivars. Significant correlations were detected between resistance to lodging and several anatomical features, including width of mechanical tissue, weight of low internodes, and width of stem walls. Morphological features that gave the best indication of improved lodging resistance were increased stem width, width of mechanical tissue layer, and stem density. Multiple linear regression analysis showed that 99% of the variation in lodging resistance could be explained by the width of the mechanical tissue layer, suggesting that solid stemmed wheat has several anatomical features for increasing resistance to lodging. In addition, microsatellite markers GWM247 and GWM340 were linked to a single solid stem QTL on chromosome 3BL in a population derived from the cross Xinongshixin(solid stem)/Line 3159(hollow stem). These markers should be valuable in breeding wheat for solid stem. 展开更多
关键词 Molecular MARKER SOLID stemmed WHEAT LODGING resistance anatomical FEATURE
在线阅读 下载PDF
Propensity score analysis demonstrated the prognostic advantage of anatomical liver resection in hepatocellular carcinoma 被引量:15
14
作者 Masayuki Ishii Toru Mizuguchi +7 位作者 Masaki Kawamoto Makoto Meguro Shigenori Ota Toshihiko Nishidate Kenji Okita Yasutohsi Kimura Thomas T Hui Koichi Hirata 《World Journal of Gastroenterology》 SCIE CAS 2014年第12期3335-3342,共8页
AIM: To compare the prognoses of hepatocellular carcinoma (HCC) patients that underwent anatomic liver resection (AR) or non-anatomic liver resection (NAR) using propensity score-matched populations.
关键词 anatomical liver resection Propensity score analysis Hepatocellular carcinoma
暂未订购
Anatomical resection of hepatocellular carcinoma: A critical review of the procedure and its benefits on survival 被引量:37
15
作者 Koo Jeong Kang Keun Soo Ahn 《World Journal of Gastroenterology》 SCIE CAS 2017年第7期1139-1146,共8页
Hepatocellular carcinoma(HCC) is the sixth most common type of cancer and the third most frequent cause of cancer-related death. Advances in preoperative assessment of HCC(e.g., imaging studies and liver function test... Hepatocellular carcinoma(HCC) is the sixth most common type of cancer and the third most frequent cause of cancer-related death. Advances in preoperative assessment of HCC(e.g., imaging studies and liver function tests), surgical techniques, and postoperative care have improved the surgical outcomes and survival of patients who undergo hepatic resection for HCC. However, in the last 20 years, the long-term survival after hepatectomy has remained unsatisfactory owing to the high rates of local recurrence and multicentric occurrence. Anatomical liver resection(AR) was introduced in the 1980 s. Although several studies have revealed tangible benefits of AR for HCC, these benefits are still debated. Because most HCCs occur in patients with liver cirrhosis and poor hepatic function, there are many factors that affect survival, including the surgical method. Nevertheless, many studies have documented the perioperative and long-term benefits of AR in various conditions. In this article, we review the results of several recently published, well-designed comparative studies of AR, to investigate whether AR provides real benefits on survival outcomes. We also discuss the potential pitfalls associated with this approach. 展开更多
关键词 Hepatocellular carcinoma CIRRHOSIS CURATIVE anatomical resection Prognosis
暂未订购
Genetic structure of needle morphological and anatomical traits of Pinus yunnanensis 被引量:4
16
作者 Yujie Huang Jianfeng Mao +4 位作者 Zhiqiang Chen Jingxiang Meng Yulan Xu Anan Duan Yue Li 《Journal of Forestry Research》 SCIE CAS CSCD 2016年第1期13-25,共13页
Pinus yunnanensis Franch. is an particular conifer tree species in Yunnan-Guizhou plateau in south- west China. The morphological and anatomical traits of needles are important to evaluate geographic variation and pop... Pinus yunnanensis Franch. is an particular conifer tree species in Yunnan-Guizhou plateau in south- west China. The morphological and anatomical traits of needles are important to evaluate geographic variation and population dynamics of conifer species. Seedlings from seven populations of P. yunnanensis were analyzed, look- ing at 22 morphological and anatomical needle traits. The results showed that variations among and within popula- tions were significantly different for all traits and the variance components within populations were generally higher than that among populations in the most tested needle traits. The proportions of three-needle fascicle were significantly different among populations. The traits related to needle size in both morphology and anatomy were positive with latitude and negative with annual temperature and precipitation. Ratio indices, including mesophyllarea/vascular bundle area, mesophyll area/resin canals area, vascular bundle area/resin canals area and mesophyU area/(resin canals area and vascular bundle area), were negatively correlated with elevation and positively corre- lated with the annual mean temperature, showing some fitness feature for the populations. Needle traits were more significantly correlated with longitude than with other four environmental factors. Needle length was significantly correlated with almost all environmental factors. First four principal components accounted for 81.596 % of the variation with eigenvalues 〉1; the differences among populations were mainly dependent on needle width, stomatal density, section areas of vascular bundle, total resin canals, and mesophyll, as well as area ratio traits. Seven populations were divided into three categories by Euclidean distance. Variations in needle traits among the populations have shown systematic microevolution in terms of geographic impact on P. yunnanensis. This study would provide empirical data to characterize adaptation and genetic variation of P. yunnanensis, which would be helpful for management of genetic resources and reason- able utilization of them in future. 展开更多
关键词 Genetic structure NEEDLE Morphologicaland anatomical traits Geographic population Pinusyunnanensis
在线阅读 下载PDF
Predicting anatomical results of surgical treatment of idiopathic macular hole 被引量:10
17
作者 Alexander A.Shpak Dmitry O.Shkvorchenko +1 位作者 Ilias Kh.Sharafetdinov Olga A.Yukhanova 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2016年第2期253-257,共5页
AIM: To determine the parameters most informative in predicting the anatomical results of surgical treatment of idiopathic full-thickness macular hole (IMH). METHODS: One hundred and sixty-two consecutive patien... AIM: To determine the parameters most informative in predicting the anatomical results of surgical treatment of idiopathic full-thickness macular hole (IMH). METHODS: One hundred and sixty-two consecutive patients (170 eyes) after primary operation for IMH were enrolled. Outcomes were classified as anatomical success when both IMH closure and restoration of the outer retinal structure were achieved. "Prospective" group included 108 patients (115 eyes) followed with optical coherence tomography (OCT) and microperimetry for ly after surgery. Potential prognostic criteria, except microperimetry data, were tested in "retrospective" group (54 patients, 55 eyes). Prognostic value of each parameter was determined using receiver operating characteristic (ROC) analysis. Combined predictive power of the best prognostic parameters was tested with the use of linear discriminant analysis. RESULTS: IMH closure was achieved in 106 eyes (92%) in the prospective group and 49 eyes (89%) in the retrospective group. Despite anatomical closure, the outer retinal structure was not restored in two eyes in the first group and in one eye in the second group. Preoperative central subfield retinal thickness demonstrated the best discriminatory capability between eyes with anatomical success and failure: area under the ROC-curve (AUC) 0.938 (95% Ch 0.881-0.995), sensitivity 64% at fixed specificity 95% (cut-off value 300um) in the prospective group; sensitivity 57% and specificity 90% in the retrospective group. Other continuous parameters except tractional hole index (AUC: 0.796, 95% Ch 0.591- 1.000) had significantly lower AUCs (P〈0.05). The best combination of the parameters, established by discriminant analysis in the prospective group, could not confirm its predictive value in the retrospective group. CONCLUSION: Preoperative central subfield retinal thickness is a strong and probably the best predictor of anatomical results of IMH surgical treatment. 展开更多
关键词 idiopathic full-thickness macular hole optical coherence tomography anatomical surgery outcome PROGNOSIS central subfield retinal thickness receiveroperating characteristic analysis
原文传递
Anatomical studies on water hyacinth (Eichhornia crassipes (Mart.) Solms) under the influence of textile wastewater 被引量:2
18
作者 MAHMOOD Qaisar 郑平 +3 位作者 SIDDIQI M. Rehan ISLAM Ejaz ul AZIM M. Rashid HAYAT Yousaf 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE EI CAS CSCD 2005年第10期991-998,共8页
Water hyacinth (Eichhornia crassipes (Mart.) Solms) is a prolific free floating aquatic macrohpyte found in tropical and subtropical parts of the earth. The effects of pollutants from textile wastewater on the anatomy... Water hyacinth (Eichhornia crassipes (Mart.) Solms) is a prolific free floating aquatic macrohpyte found in tropical and subtropical parts of the earth. The effects of pollutants from textile wastewater on the anatomy of the plant were studied. Water hyacinth exhibits hydrophytic adaptations which include reduced epidermis cells lacking cuticle in most cases, presence of large air spaces (7~50 μm), reduced vascular tissue and absorbing structures. Textile waste significantly affected the size of root cells.The presence of raphide crystals was noted in parenchyma cells of various organs in treated plants. 展开更多
关键词 EICHHORNIA crassipes Water hyacinth TEXTILE wastewater anatomical STUDIES
在线阅读 下载PDF
Effects of Chronic Stress of Cadmium and Lead on Anatomical Structure of Tobacco Roots 被引量:2
19
作者 YUAN Zu-li XIONG Shu-ping +1 位作者 LI Chun-ming MA Xin-ming 《Agricultural Sciences in China》 CAS CSCD 2011年第12期1941-1948,共8页
Cadmium (Cd2+) is one of the major widespread environmental pollutants, and can cause serious problems to all organisms. Lead (Pb2+) is another wide spread dangerous heavy metal. Tobacco is a popular growing eco... Cadmium (Cd2+) is one of the major widespread environmental pollutants, and can cause serious problems to all organisms. Lead (Pb2+) is another wide spread dangerous heavy metal. Tobacco is a popular growing economic crop in China. Most tobacco growing region soils contain excessive Cd2+ and Pb2+. To assess anatomic changes of tobacco roots under Cd2+, Pb2+, and Cd2++pb2+ chronic stress, a pot experiment was carried out in field. The tobacco seedlings with 6 leaves were transplanted to pots in which soil was placed. The amounts of Cd2+ added to soil were 0, 3, 6, 10, 30, 60, and 100 mg kg-1 dry soil. The amounts of Pb2+ added to soil were 0, 150, 300, 450, 600, 750, and 1 000 mg kg-1 dry soil. The amounts of Cd2++Pb2+ added to soil were 0+0, 3+150, 6+300, 10+450, 30+600, 60+750, and 100+1000 mg kg-1 dry soil. The contents of Cd2+ and Pb2+ in root systems were determined by inductively coupled plasma, and the anatomical structure was studied by method of paraffin sectioning. The results revealed that the amounts of exchangeable Cd2+ and Pb2+ and carbonate bound Cd2+ and Pbz+ in soil increased with the amounts of Cd2+ and Pb2+ added to soil, and the contents of both Cd2+ and Pb1+ in roots were significantly increased along with stress time and the amounts of Cd2+ and Pb2+ added to soil. The growing of tobacco in Cd2+ and Cd2++Pb2+ polluted soil for 50, 100, and 150 d resulted in some abnormal extemal morphological and anatomical changes in ripe region of lateral roots. All the abnormal roots had abnormal vascular cylinders, and the ratio of abnormal extemal morphological and anatomical changes of roots positively correlated with the Cd2+ contents in roots and stress time. While, there were no abnormal external morphological and anatomical changes of roots under Pb2+ stress. It was suggested that Cd2+ stress could cause abnormal anatomic changes of roots, but Pb2+ stress could not. 展开更多
关键词 TOBACCO ROOTS Cd2+ Pb2+ stress anatomical structure
在线阅读 下载PDF
Morphogenesis,Anatomical Observation and Primary Genetic Analysis of a Multi-glume Floral Organ Mutant in Rice 被引量:3
20
作者 PAN Cun-hong LI Ai-hong +5 位作者 Wu Ru ZHANG Ya-fang TANG Wen Wu Chang-yin ZHANG Qi-fa PAN Xue-biao 《Rice science》 SCIE 2006年第4期227-233,共7页
A multi-glume (mg) mutant was obtained by screening the T-DNA inserted mutant pool. Anatomical observation revealed that the florets of the mutant showed elongated leafy paleas/lemmas and palea/lemma-like structures... A multi-glume (mg) mutant was obtained by screening the T-DNA inserted mutant pool. Anatomical observation revealed that the florets of the mutant showed elongated leafy paleas/lemmas and palea/lemma-like structures, just like multi-glumes. Among the 215 observed florets of the mutant, 14.27% were failed to produce pistil and stamens, 23.72% showed extra floret generated on the same rachilla, while 62.01% consisted of one to nine stamens and one to three pistils in a single floret. On the other hand, in some cases the transparent bulged vesile-like tissue could be observed at the basis of filament. The mutant showed glumaceous Iodicules, which prevented the florets from opening in natural conditions, while the absolute male and female sterility was an obvious character of the current mutant. Observation on the process of floral organ morphogenesis by a scanning electron microscopy (SEM) indicated that no phenotype difference in floret primordia was found between the wild-type and the mutant. Meanwhile, for the mutant, the beginning of stamen and pistil primordial differentiation was later than the wild type and the palea/lemma-like structure continued to differentiate after the formation of normal palea and lemma. Furthermore, in the mutant the asymmetrical division of floral primordial caused variation in the number of stamens and pistils. Therefore, the genetic analyses indicated that the mutation phenotype was a recessive trait controlled by a single gene and co-segregated with the T-DNA. Based on the phenotypic characteristics, it could be deduced that the mutant was the result of homeotic conversion from the function of the class E genes in ABCD model. 展开更多
关键词 rice (Oryza sativa) multi-glume mutant anatomical structure MORPHOGENESIS genetic analysis
在线阅读 下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部