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排序方式: 共有419条查询结果,搜索用时 265 毫秒
91.
Objective
To investigate the effect of surgical decompression on painful diabetic peripheral neuropathy (DPN) patients and discuss the role which pain distribution and characterization play in the management of painful DPN as well as the underlying mechanism involved.Methods
A total of 306 patients with painful diabetic lower-extremity neuropathy were treated with Dellon surgical nerve decompression in our department. Clinical evaluation including Visual analogue scale (VAS), Brief Pain Inventory Short Form for diabetic peripheral neuropathy (BPI-DPN) questionnaire, two-point discrimination (2-PD), nerve conduction velocity (NCV) and high-resolution ultrasonography (cross-sectional area, CSA) were performed in all cases preoperatively, and at 6 month intervals for 2 years post-decompression. The patients who underwent surgery were retrospectively assigned into two subgroups (focal and diffuse pain) according to the distribution of the diabetic neuropathic pain. The control group included 92 painful DPN patients without surgery.Results
The levels of VAS, scores in BPI-DPN, 2-PD, NCV results and CSA were all improved in surgical group when compared to the control group (P<0.05). More improvement of VAS, scores in BPI-DPN and CSA was observed in focal pain group than that in diffuse group (P<0.05).Conclusions
Efficacy of decompression of multiple lower-extremity peripheral nerves in patients with painful diabetic neuropathy was confirmed in this study. While both focal and diffuse group could benefit from surgical decompression, pain relief and morphological restoration could be better achieved in focal group. 相似文献92.
Kyoko Sako-Kubota Nobutoshi Tanaka Shigenori Nagae Wenxiang Meng Masatoshi Takeichi 《Molecular biology of the cell》2014,25(24):3851-3860
The adherens junction (AJ) plays a crucial role in maintaining cell–cell adhesion in epithelial tissues. Previous studies show that KIFC3, a minus end–directed kinesin motor, moves into AJs via microtubules that grow from clusters of CAMSAP3 (also known as Nezha), a protein that binds microtubule minus ends. The function of junction-associated KIFC3, however, remains to be elucidated. Here we find that KIFC3 binds the ubiquitin-specific protease USP47, a protease that removes ubiquitin chains from substrates and hence inhibits proteasome-mediated proteolysis, and recruits it to AJs. Depletion of KIFC3 or USP47 promotes cleavage of E-cadherin at a juxtamembrane region of the cytoplasmic domain, resulting in the production of a 90-kDa fragment and the internalization of E-cadherin. This cleavage depends on the E3 ubiquitin protein ligase Hakai and is inhibited by proteasome inhibitors. E-cadherin ubiquitination consistently increases after depletion of KIFC3 or USP47. These findings suggest that KIFC3 suppresses the ubiquitination and resultant degradation of E-cadherin by recruiting USP47 to AJs, a process that may be involved in maintaining stable cell–cell adhesion in epithelial sheets. 相似文献
93.
引种桉树对本地生物多样性的影响 总被引:8,自引:0,他引:8
桉树以速生和适应多种环境的特性成为世界著名的造林树种.但引种桉树对环境可能产生负面影响,如导致土地退化、地下水水位下降和多样性降低等,特别是对林下本地生物物种多样性的影响及其原因还存有争议.本文对此进行了综述,认为大部分桉树人工林本地物种数量低于天然林,一般不高于乡土树种人工林,但总体上好于其他外来树种人工林.导致桉树人工林生物多样性低的原因主要是桉树的生理生态特性、人类不合理的规划和砍伐等,其中人为因素起主导作用.若根据引种地的群落性质,通过严格的设计和科学管理,可以将这种负面影响最小化.应按照有利于群落正常发育和植被更新的方式栽种桉树人工林,保留天然植被,减少人为干扰,从而减轻引种桉树的负面影响. 相似文献
94.
异源nif LacZ融合基因在粪产碱菌A15 6 1中的表达活性随盐浓度增加而升高 ,然后逐渐降低 ,nifH LacZ融合基因可以正常表达的盐浓度在 0 .1%~0 .5 %之间 ,盐浓度为 0 .0 5 %时活性最高。A15 6 1在盐浓度为 0 .0 6 %时趋化能力最强 ,随着盐浓度的提高逐渐下降 ,当盐浓度为 3 .0 %时完全丧失趋化能力。一定的盐浓度 (0 .5 % )对固氮粪产碱菌的根表定殖有促进作用 ,该条件下根表定殖的菌体数远大于对照。 3种nif LacZ融合基因在根内的表达部位有显著差异。nifH的表达部位主要分布于根的皮层薄壁组织细胞间隙 ,在条件适宜 (无铵和微量氧 )的部位或某些特殊位置如侧根伸出部位高水平表达。盐胁迫下水稻 耐盐粪产碱菌A15 6 1的联合固氮效率明显高于A15 6 1纯培养物 相似文献
95.
蚤消化系统的研究:14种蚤前胃的结构 总被引:2,自引:0,他引:2
蚤的前胃结构与其传病机制密切相关。 本文应用解剖、组织切片和扫描电镜研究14种蚤的前胃。前胃的外部形态可分为:球状、椭球状、管状和圆台状。前胃刺内部有原生质。 前胃刺的末端形态可分为:钩形、弯叉形、叶形、针形、矛形、喇叭口形、“W”形、大叉形、小叉形、马刀形、锥形和舌形。 前胃刺包括有齿刺和无齿刺两类,有齿刺上齿的分布茫固有:1/2、1/3、1/4、2/3和刺全长。未观察到花蠕形蚤 yermipsylla alakurt 和缓慢细蚤Leptopsylla sehnis的前胃刺上有齿。 前胃刺末端形态和齿的分布呈现出科的相似性。 前胃刺基部的形态有:四棱形、正方形、五边形、不规则五边形、六边形、卵形和圆形。致痒蚤Pulex irrirans和印鼠客蚤Xenopsylla cheopis的前胃刺较粗长、骨化强、在刺两侧具较密的齿且多分布于刺的一半以上,这些特征可能适宜于鼠疫杆菌的生存与大量聚集。没有观察到俊潜蚤Tunga callida的前胃和前胃刺。 相似文献
96.
97.
Neurochemical Research - S-oxiracetam (S-ORC), a nootropic drug, was used to protect against ischemic stroke by lessening the blood brain barrier dysfunction and inhibiting neuronal apoptosis.... 相似文献
98.
99.
廖学焜;郭慧然;陈文祥 《武汉植物学研究》1988,6(3):247-252
应用高效液相色谱技术,分离分析大豆油、花生油、芝麻油的甘油三酯组成,测试表明,大豆油的主要甘油三酯为LLL、LLO、LLP、OLO和PLO;花生油的主要甘油三酯为OLO、LLO、PLO;芝麻油的主要甘油三酯为LLO、OLO、POO和LLL。 相似文献
100.
Emily V. Wong Shawn Gray Wenxiang Cao Rachel Montpetit Ben Montpetit Enrique M. De La Cruz 《Journal of molecular biology》2018,430(14):2080-2095
Dbp5, DDX19 in humans, is an essential DEAD-box protein involved in mRNA export, which has also been linked to other cellular processes, including rRNA export and translation. Dbp5 ATPase activity is regulated by several factors, including RNA, the nucleoporin proteins Nup159 and Gle1, and the endogenous small-molecule inositol hexakisphosphate (InsP6). To better understand how these factors modulate Dbp5 activity and how this modulation relates to in vivo RNA metabolism, a detailed characterization of the Dbp5 mechanochemical cycle in the presence of those regulators individually or together is necessary. In this study, we test the hypothesis that Nup159 controls the ADP-bound state of Dbp5. In addition, the contributions of Mg2+ to the kinetics and thermodynamics of ADP binding to Dbp5 were assessed. Using a solution based in vitro approach, Mg2+ was found to slow ADP and ATP release from Dbp5 and increased the overall ADP and ATP affinities, as observed with other NTPases. Furthermore, Nup159 did not accelerate ADP release, while Gle1 actually slowed ADP release independent of Mg2+. These findings are not consistent with Nup159 acting as a nucleotide exchange factor to promote ADP release and Dbp5 ATPase cycling. Instead, in the presence of Nup159, the interaction between Gle1 and ADP-bound Dbp5 was found to be reduced by ~ 18-fold, suggesting that Nup159 alters the Dbp5–Gle1 interaction to aid Gle1 release from Dbp5. 相似文献