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In the past decade, the discovery, synthesis, and evaluation for hundreds of CD38 covalent and non‐covalent inhibitors has been reported sequentially by our group and partners; however, a systematic structure‐based guidance is still lacking for rational design of CD38 inhibitor. Here, we carried out a comparative analysis of pharmacophore features and quantitative structure–activity relationships for CD38 inhibitors. The results uncover that the essential interactions between key residues and covalent/non‐covalent CD38 inhibitors include (i) hydrogen bond and hydrophobic interactions with residues Glu226 and Trp125, (ii) electrostatic or hydrogen bond interaction with the positively charged residue Arg127 region, and (iii) the hydrophobic interaction with residue Trp189. For covalent inhibitors, besides the covalent effect with residue Glu226, the electrostatic interaction with residue Arg127 is also necessary, while another hydrogen/non‐bonded interaction with residues Trp125 and Trp189 can also be detected. By means of the SYBYL multifit alignment function, the best CoMFA and CoMSIA with CD38 covalent inhibitors presented cross‐validated correlation coefficient values (q2) of 0.564 and 0.571, and non‐cross‐validated values (r2) of 0.967 and 0.971, respectively. The CD38 non‐covalent inhibitors can be classified into five groups according to their chemical scaffolds, and the residues Glu226, Trp189, and Trp125 are indispensable for those non‐covalent inhibitors binding to CD38, while the residues Ser126, Arg127, Asp155, Thr221, and Phe222 are also important. The best CoMFA and CoMSIA with the F12 analogues presented cross‐validated correlation coefficient values (q2) of 0.469 and 0.454, and non‐cross‐validated values (r2) of 0.814 and 0.819, respectively.  相似文献   
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目的:了解桂林市2008年及以后确诊的经性传播的人类免疫缺陷病毒1型( HIV-1)感染者的流行病学及亚型的分布情况。方法选取样本100例,收集流行病学资料,采集抗凝全血,提取病毒RNA,RT-PCR法行gag基因扩增,对产物进行测序和分析。结果100例样本中男女比例为2.125∶1;青壮年年龄组(20~49岁)患者为54%,>50岁年龄组患者为45%;职业为农民的患者为40%,学生为6%;初中及以下文化水平患者占69%;经异性和同性性接触途径传播的分别为93%、7%。100例样本最终成功扩增得到61例样本的 gag 基因序列, CRF01-AE 重组亚型48例, CRF07-BC重组亚型8例,B亚型5例。结论应更加重视婚检、孕检的艾滋病抗体筛查;关注老年人群经性接触途径感染艾滋病的现象;采取针对低素质人群的有效防治措施;随着主要传播途径和主要亚型的变化,迫切需要对高危人群进行宣传教育和行为干预以阻断HIV/AIDS的流行和传播。  相似文献   
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目的::探讨肝局灶结节性增生( FNH)的临床及影像学特点、病理形态、免疫组织化学特征及鉴别诊断。方法:分析9例FNH的临床资料及发病特点、影像学特征、组织病理形态及免疫表型、细胞角蛋白( CK8/18、CK7)、CD34、甲胎蛋白和Ki-67的表达。并进行相关文献复习。结果:影像学观察FNH通常为孤立的结节,平扫为等密度或稍低密度,中央可见低密度瘢痕。FNH病理大体表现为境界清楚、中央有纤维瘢痕的结节性肿块。镜下纤维间隔将肝组织分割成大小不等、形状不规则的结节,可见厚壁血管及增生的小胆管。免疫组织化学染色CK8/18、CK7结节内和周边增生的小胆管阳性表达;CD34结节内的血窦内皮细胞及纤维间隔的血管内皮细胞阳性表达。甲胎蛋白结节内增生胆管和肝细胞均阴性,Ki-67阳性指数较低。结论:FNH是对畸形血管的肝细胞反应性增生,是一种良性瘤样病变,对于诊断明确的无症状者手术切除后,可定期随诊或复查。  相似文献   
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中医药学和西医药学共有的载体是化学物质,为此提出中药特性化学和化学中药学旨在架起中药与西药之间的桥梁。本文首次提出中药特性化学和化学中药学的理论与研究方法,为有效促进和完善中医药学和西医药学的理论及其融合,尤其是西药中药化奠定基础。  相似文献   
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Digital games have been used as stressors in a range of disciplines for decades. Nonetheless, the underlying characteristics of these stressors and the study in which the stressor was applied are generally not recognized for their moderating effect on the measured physiological stress responses. We have therefore conducted a meta‐analysis that analyzes the effects of characteristics of digital game stressors and study design on heart rate, systolic and diastolic blood pressure, in studies carried out from 1976 to 2012. In order to assess the differing quality between study designs, a new scale is developed and presented, coined reliability of effect size. The results show specific and consistent moderating functions of both game and study characteristics, on average accounting for around 43%, and in certain cases up to 57% of the variance found in physiological stress responses. Possible cognitive and physiological processes underlying these moderating functions are discussed, and a new model integrating these processes with the moderating functions is presented. These findings indicate that a digital game stressor does not act as a stressor by virtue of being a game, but rather derives its stressor function from its characteristics and the methodology in which it is used. This finding, together with the size of the associated moderations, indicates the need for a standardization of digital game stressors.  相似文献   
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The potential of constructing useful DNA-based facial composites is forensically of great interest. Given the significant identity information coded in the human face these predictions could help investigations out of an impasse. Although, there is substantial evidence that much of the total variation in facial features is genetically mediated, the discovery of which genes and gene variants underlie normal facial variation has been hampered primarily by the multipartite nature of facial variation. Traditionally, such physical complexity is simplified by simple scalar measurements defined a priori, such as nose or mouth width or alternatively using dimensionality reduction techniques such as principal component analysis where each principal coordinate is then treated as a scalar trait. However, as shown in previous and related work, a more impartial and systematic approach to modeling facial morphology is available and can facilitate both the gene discovery steps, as we recently showed, and DNA-based facial composite construction, as we show here. We first use genomic ancestry and sex to create a base-face, which is simply an average sex and ancestry matched face. Subsequently, the effects of 24 individual SNPs that have been shown to have significant effects on facial variation are overlaid on the base-face forming the predicted-face in a process akin to a photomontage or image blending. We next evaluate the accuracy of predicted faces using cross-validation. Physical accuracy of the facial predictions either locally in particular parts of the face or in terms of overall similarity is mainly determined by sex and genomic ancestry. The SNP-effects maintain the physical accuracy while significantly increasing the distinctiveness of the facial predictions, which would be expected to reduce false positives in perceptual identification tasks. To the best of our knowledge this is the first effort at generating facial composites from DNA and the results are preliminary but certainly promising, especially considering the limited amount of genetic information about the face contained in these 24 SNPs. This approach can incorporate additional SNPs as these are discovered and their effects documented. In this context we discuss three main avenues of research: expanding our knowledge of the genetic architecture of facial morphology, improving the predictive modeling of facial morphology by exploring and incorporating alternative prediction models, and increasing the value of the results through the weighted encoding of physical measurements in terms of human perception of faces.  相似文献   
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