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21.
Supravalvular aortic stenosis (SVAS) is an inherited obstructive vascular disease that affects the aorta, carotid, coronary and pulmonary arteries. Previous molecular genetic data have led to the hypothesis that SVAS results from mutations in the elastin gene, ELN. In these studies, the disease phenotype was linked to gross DNA rearrangements (35 and 85 kb deletions and a translocation) in three SVAS families. However, gross rearrangements of ELN have not been identified in most cases of autosomal dominant SVAS. To define the spectrum of ELN mutations responsible for this disorder, we refined the genomic structure of human ELN and used this information in mutational analyses. ELN point mutations co-segregate with the disease in four familial cases and are associated with SVAS in three sporadic cases. Two of the mutations are nonsense, one is a single base pair deletion and four are splice site mutations. In one sporadic case, the mutation arose de novo. These data demonstrate that point mutations of ELN cause autosomal dominant SVAS.   相似文献   
22.
急性上颌窦炎实验动物模型的建立   总被引:1,自引:1,他引:1  
目的:拟建立急性上颌窦炎的实验动物模型,并探讨窦口的阻塞和致病菌的毒力在急性上颌窦炎的发病机制中的地位。方法:第一天,阻塞单侧窦口,对侧做假手术。次日,注入0.5ml108CFU/ml肺炎链球菌悬浮液。第五天处死动物、观察、分离培养细胞、取材和制作切片。结果:阻塞上颌窦口和注入肺炎链球菌的联合组,鼻部症状明显;进食量减少;鼻窦粘膜水肿、微红,具有较多脓性分泌物,微血管扩张,白细胞浸润;肺炎链球菌的重新分离培养率为100%(与其余组比较具有显著意义P<0.01)。而仅阻塞上颌窦口或仅注入肺炎链球菌或假手术均无明显临床症状及组织病理学改变,细胞培养率也低。结论:窦口的阻塞和致病菌的毒力是上颌窦炎发生发展的重要的条件,其中,窦口的阻塞起着关键性作用;联合阻塞窦口并注入有荚膜的肺炎链球菌能较理想地建立急性上颌窦炎实验动物模型。  相似文献   
23.
DNA studies of the translocation t(15;17) in acute promyelocytic leukemia (APL) have shown that the retinoic acid receptor alpha (RARA) gene on chromosome 17 is juxtaposed to the promyelocytic leukemia (PML) gene on chromosome 15. The PML breakpoints have been mapped to 3 clusters: bcr1, bcr2, and bcr3. We have examined the PML breakpoint distribution in a series of 33 Chinese patients with APL Twenty-two patients fell within bcr1, 2 within bcr2, and 9 within bcr3. The primary structure of the reciprocal chromosome translocation joints of one patient and that of their normal counterparts have been determined and compared to those of 2 previously reported cases. These studies revealed possible topoisomerase II cleavage sites close to the breakpoints and suggested implications of DNA attachment sites to nuclear matrix. We propose that these features are relevant to the process of illegitimate recombination generating the translocation. © 1993 Wiley-Liss, Inc.  相似文献   
24.
耿排力 《现代免疫学》1997,17(4):228-231
作者探讨了鸡蛋过敏特应性皮炎(AD)患儿外周血单个核细胞(PBMCs)对卵白蛋白(OA)刺激的增殖反应并观察了酮替酚(KF)对此反应的影响.结果提示AD患儿的PBMCs增殖反应显著高于健康儿童;KF可剂量依赖性地抑制鸡蛋过敏AD患儿PBMCs对OA刺激的增殖反应,且这一效应可通过KF抑制T细胞的作用而得以实现.KF对植物血凝素(PHA)和破伤风类毒素(TT)诱导的PBMCs增殖反应无抑制作用.这说明KF只抑制食物过敏AD患者PBMCs对食物抗原的特异性增殖反应.  相似文献   
25.
目的 明确 5C5蛋白为分化抗原 ,检测其在人免疫细胞的表达 ,以及它的信号传导作用。方法 用 5C5蛋白免疫小鼠 ,制备抗 5C5蛋白的单抗。用反义技术制备 5C5蛋白表达抑制的 3D5细胞。用免疫荧光染色和Western印迹确定 5C5单抗的特异性。用胞膜蛋白免疫沉淀和流式细胞术确定其分化抗原的性质。用双色免疫荧光染色流式细胞术检测 5C5分化抗原在多种人免疫细胞的表达。用Fura 3 AM试剂作探针 ,用激光共聚焦显微镜观察胞内Ca2 + 浓度的变化。结果 制备了抗 5C5蛋白的特异性单抗。用 5C5单抗作探针 ,从 3D5细胞膜免疫沉淀到 1条相对分子质量 (Mr)为 19× 10 3的蛋白带 ,并在活 3D5细胞见阳性免疫荧光染色。 5C5分化抗原在人周围血CD19+ 、CD14 + 、CD4 + 、CD8+ 和CD5 6 + 细胞的表达率分别为 (33.4 7± 7.9) %、(86 .13± 6 .7) %、(15 .79± 7.1) %、(18.11±12 .77) %和 (11.76± 7.4 7) % ,在人免疫细胞株的表达率分别为 5 8.0 % (Nalm6 )、72 .7% (3D5 )、5 3.6 %(BJAB)、6 1.0 % (Daudi)、6 .9% (SKW6 )、6 .3% (Jurkat)、5 .8% (Peer)、2 1.3% (K5 6 2 )和 39.1% (U937)。3D5细胞在 5C5单抗刺激下 ,胞内Ca2 + 浓度逐渐增高 ,可达 2倍左右 ,对照小鼠Ig则无此作用。结论5C5蛋白为一个分化抗原 ,在人周  相似文献   
26.
Ding Y  He L  Zhang Q  Huang Z  Che X  Hou J  Wang H  Shen H  Qiu L  Li Z  Geng J  Cai J  Han H  Li X  Kang W  Weng D  Liang P  Jiang S 《The Journal of pathology》2004,203(2):622-630
We previously identified the major pathological changes in the respiratory and immune systems of patients who died of severe acute respiratory syndrome (SARS) but gained little information on the organ distribution of SARS-associated coronavirus (SARS-CoV). In the present study, we used a murine monoclonal antibody specific for SARS-CoV nucleoprotein, and probes specific for a SARS-CoV RNA polymerase gene fragment, for immunohistochemistry and in situ hybridization, respectively, to detect SARS-CoV systematically in tissues from patients who died of SARS. SARS-CoV was found in lung, trachea/bronchus, stomach, small intestine, distal convoluted renal tubule, sweat gland, parathyroid, pituitary, pancreas, adrenal gland, liver and cerebrum, but was not detected in oesophagus, spleen, lymph node, bone marrow, heart, aorta, cerebellum, thyroid, testis, ovary, uterus or muscle. These results suggest that, in addition to the respiratory system, the gastrointestinal tract and other organs with detectable SARS-CoV may also be targets of SARS-CoV infection. The pathological changes in these organs may be caused directly by the cytopathic effect mediated by local replication of the SARS-CoV; or indirectly as a result of systemic responses to respiratory failure or the harmful immune response induced by viral infection. In addition to viral spread through a respiratory route, SARS-CoV in the intestinal tract, kidney and sweat glands may be excreted via faeces, urine and sweat, thereby leading to virus transmission. This study provides important information for understanding the pathogenesis of SARS-CoV infection and sheds light on possible virus transmission pathways. This data will be useful for designing new strategies for prevention and treatment of SARS.  相似文献   
27.
Mutations in the PKD1 gene are responsible for autosomal dominant polycystic kidney disease (ADPKD). Although PKD1 has been cloned and shown to be expressed at high levels in the fetal ureteric bud and ADPKD cystic epithelia in the human kidney, the function of its encoded protein, "polycystin-1" is unknown. In this study we used primary and immortalized human renal epithelial cell lines derived from normal fetal, adult, and ADPKD kidneys, that endogenously express PKD1, to study the biologic function of the polycystin-1 protein. ADPKD renal epithelial cells expressed high levels of polycystin-1 protein and showed increased adhesion to type I collagen by comparison with normal adult human renal epithelia that expressed little polycystin. Adherent ADPKD cells also expressed high levels of alpha2beta1-integrin and their attachment was inhibited by a functional monoclonal antibody to alpha2-integrin. Double labeling and confocal microscopy as well as coimmunoprecipitation analysis showed overlapping colocalization of polycystin-1 with alpha2beta1-integrin as well as with the focal adhesion proteins vinculin and paxillin in multiprotein clusters localized to focal areas of cell membrane contact with type I collagen matrix after short periods of attachment. Immunoprecipitation and Western immunoblot studies also showed that polycystin-1 was posttranslationally modified by tyrosine phosphorylation. These studies suggest that the PKD1-encoded protein is part of a large multiprotein complex in epithelial cells that functions in the regulation of extracellular matrix interactions with the plasma membrane and cell cytoskeleton.  相似文献   
28.
29.
目的:观察脂多糖(LPS)对大鼠肺微血管内皮细胞(RPMVECs)G蛋白的影响及甲基强的松龙的干预作用。方法:用流式细胞技术(FCM)检测G蛋白亚型的变化。结果:①10μg/ml LPS作用于RPMVECs30和90min后,Gsα蛋白水平较对照组显著下降。甲基强的松龙干预30和90min后,对LPS致RPMVECs膜Gsα蛋白水平的变化有显著抑制作用。②10μg/ml LPS作用于RPMVECs30和90min后,Giα蛋白水平较对照组显著下降。甲基强的松龙干预30和90min后,对LPS致RPMVECs膜Giα蛋白水平的变化有显著抑制作用。结论:①LPS诱导RPMVECS Gsα和Giα蛋白水平的变化可能是LPS诱导RPMVECs单层通透性增加的机制之一。②甲基强的松龙参与抑制LPS诱导RPMVECs单层通透性增加的作用。  相似文献   
30.
在聚合物固体电解质(聚乙二醇不饱和聚酯网络-LiClO4)中进行吡咯聚合原位制得了聚吡咯/聚合物固体电解质双层复合膜。用扫描电镜观察复合膜的界面结构,用循环伏安和交流阻抗法研究了复合膜的电化学杂脱掺杂性能。结果表明,聚吡咯/聚合物固体电解质双层复合膜具有相互穿插渗透的固/固密接界面结构,这种界面结构改善了聚吡咯和聚俣物固体电解质间的界面接触,提高了聚吡咯在聚俣物固体电解质中的电化学掺杂脱掺杂性能。  相似文献   
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