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目的:研究对比三种抗癫痫药(苯妥因钠、丙戊酸钠、卡马西平)对癫痫患者脑电图的背景影响。方法:选取我院于2009年3月至2011年2月收治的60例癫痫患者,随机分为苯妥因钠(PHT)、卡马西平(CBZ)和丙戊酸钠(SVP)组各20例,动态观察各组患者于治疗期间痫样波放电的频度和EEG背景的变化。结果:EEG痫样波放电的抑制率以SVP最为明显,而CBZ在EEG背景活动影响方面均比其他两组显著。结论:三种药物对癫痫波放电的抑制顺序是SVP〉PHT〉CBZ,SVP组明显优于其他两组。  相似文献   
225.
目的:脑卒中是威胁人类健康三大疾病之一,是我国成人致残的首要原因,其中80%是缺血性卒中。本文意在研究血清胆红素水平与缺血性卒中严重程度、发病机理以及颈动脉粥样硬化斑块的关系,以进一步为防治缺血性卒中的发生、发展提供新的途径。方法:选择缺血性脑卒中患者(观察组)150例和同期健康体检者(对照组)150例,分别测定两组的血清总胆红素水平(TBIL)、间接胆红素(DBIL)、直接胆红素(IBIL),并对病例组进行TOAST分型、NIHSS评分及颈部血管超声检查。比较两组间血清胆红素,及观察组内不同分型组间血清胆红素的差异。结果:缺血性卒中患者TBIL、DBIL水平显著高于正常对照组,差异具有统计学意义(P〈0.05)。缺血性卒中患者按TOAST分型各亚型间血清TBIL、DBIL、IBIL水平差异无统计学意义(P〉0.05)。中重型脑梗死组与轻型脑梗死组比较,血清TBIL、DBIL、IBIL浓度均明显升高,差别具有统计学意义(P〈0.05)。缺血性卒中患者中有动脉粥样硬化斑块形成组血清TBIL、DBIL水平低于颈部动脉内膜光滑、完整者组,差别有统计学意义(P〉0.05)。结论:缺血性卒中患者血清胆红素升高,参与急性应激反应,可能作为衡量缺血性卒中严重程度的指标之一;高水平血清胆红素可能预防颈动脉粥样硬化斑块的形成,从而预防缺血性卒中的发生。  相似文献   
226.
Much remains to be discovered about the fate of recent memories in the human brain. Several studies have reported the reactivation of learning-related cerebral activity during post-training sleep, suggesting that sleep plays a role in the offline processing and consolidation of memory. However, little is known about how new information is maintained and processed during post-training wakefulness before sleep, while the brain is actively engaged in other cognitive activities. We show, using functional magnetic resonance imaging, that brain activity elicited during a new learning episode modulates brain responses to an unrelated cognitive task, during the waking period following the end of training. This post-training activity evolves in learning-related cerebral structures, in which functional connections with other brain regions are gradually established or reinforced. It also correlates with behavioral performance. These processes follow a different time course for hippocampus-dependent and hippocampus-independent memories. Our experimental approach allowed the characterization of the offline evolution of the cerebral correlates of recent memories, without the confounding effect of concurrent practice of the learned material. Results indicate that the human brain has already extensively processed recent memories during the first hours of post-training wakefulness, even when simultaneously coping with unrelated cognitive demands.  相似文献   
227.

Background  

To gain more insight in whether failure of intrauterine insemination (IUI) treatment in patients with idiopathic subfertility could be related to diminished fertilization, the aim of this study is to compare the fertilization of an initial IVF procedure after six cycles of IUI and the fertilization of an initial IVF procedure without preceding IUI cycles in couples with idiopathic subfertility.  相似文献   
228.
目的:观察长期家庭氧疗配合呼吸操治疗慢性阻塞性肺疾病(COPD)的临床效果。、方法:选择本院收治的COPD患者80例,随机分为研究组和对照组,各40例,两组均给予常规治疗,研究组同时由医务人员指导给予家庭氧疗和呼吸操训练,随访1年.观察两组治疗前、治疗后6个月和1年肺功能,应用StGeorge’S呼吸问卷(SGRQ)评价生存质量、结果:研究组1年内急性发作1次5人,2次2人,3次及以上1人,对照组1年内急性发作1次9人,2次7人,3次及以上4人(P〈0.05);研究组治疗后6个月、1年用力肺活量(FVC)、第1秒用力呼气容积(FEVl)和FEVl/FVC均明显升高(P〈0.05),对照组治疗后6个月、1年FVC、FEVI/FVC与治疗前比较无统计学差异(P〉0.05);研究组治疗后6个月、1年SGRQ明显降低(P〈0.05),对照组治疗后6个月、1年SGRQ与治疗前比较无统计学差异(P〉0.05).结论:家庭氧疗配合呼吸操能明显改善COPD患者肺功能,延缓患者肺功能恶化,提高患者生存质量。  相似文献   
229.
Parsons L  Eisenstein E  Orban J 《Biochemistry》2001,40(37):10979-10986
A novel bacterial ribosome binding protein, protein Y (also known as YfiA), was recently shown to reside at the 30S/50S subunit interface and to stabilize the ribosomal 70S complex against dissociation at low magnesium ion concentrations. We report here the three-dimensional NMR structure in solution of a homologue from Haemophilus influenzae, HI0257, that has 64% sequence identity to protein Y. The 107 residue protein has a beta-alpha-beta-beta-beta-alpha folding topology with two parallel alpha-helices packed against the same side of a four-stranded beta-sheet. The closest structural relatives are proteins with the double-stranded RNA-binding domain (dsRBD) motif although there is little (<10%) sequence homology. The most immediate differences between the dsRBD and HI0257 structures are that (1) HI0257 has a larger beta-sheet motif with an extra beta-strand at the N-terminus, (2) the helices are parallel in HI0257 but at an angle of about 30 degrees to each other in the dsRBD, and (3) HI0257 lacks the extended loop commonly seen between the first and second beta-strands of the dsRBD. Further, an analysis of the surface electrostatic potential in HI0257 and the dsRBD family reveals significant differences in the location of contiguous positively (and negatively) charged regions. The structural data, in combination with sequence analysis of HI0257 and its homologues, suggest that the most likely mode of RNA recognition for HI0257 may be distinct from that of the dsRBD family of proteins.  相似文献   
230.
Residue-specific exchange rates of 223 amide protons in free and prodomain-complexed subtilisin were determined in order to understand how the prodomain binding affects the energetics of subtilisin folding. In free subtilisin, amide protons can be categorized according to exchange rate: 74 fast exchangers (rates > or = 1 h(-1)); 52 medium exchangers (rates between 1 h(-1) and 1 day(-1)); 31 slow exchangers (rates between 1 day(-1) and 0.001 day(-1)). The remaining 66 amide proteins did not exchange detectibly over 9 months (k(obs) < year(-1)) and were denoted as core protons. Core residues occur throughout the main structural elements of subtilisin. Prodomain binding results in high protection factors (100-1000) in the central beta-sheet, particularly in the vicinity of beta-strands S5, S6, and S7 and the connecting loops between them. These connecting loops provide the ligands to the cation at metal site B. Overall, prodomain binding seems to facilitate the organization of the entire central beta-sheet and alpha-helix C in the left-handed crossover connection between beta-strands two and three. It also appears to facilitate the isomerization of multiple prolines late in folding, allowing the formation of metal site B. The gain of stability region around site B comes at the cost of stability in regions more distal to prodomain binding: the C-terminal alpha-helix H and the N-terminal alpha-helices A and B. The acceleration of exchange in these regions by prodomain binding reveals an antagonism between the folding intermediate and the full native structure. This antagonism helps to explain why the prodomain is needed to stabilize the folding intermediate as well as why the unfolding of free subtilisin seldom occurs via this intermediate.  相似文献   
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