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21.
 Induction of heat shock proteins (HSPs) following cell injury contributes to the protection of vital cell functions. It was, therefore, of interest to study the effects of transient renal ischaemia on the abundance and distribution of two HSPs, HSP25 and HSP72, in renal tissue using Western-blot techniques. Analyses were performed on the supernatant (HSP25, HSP72) and pellet (HSP25) of homogenates obtained from cortex (CX) and outer (OM) and inner (IM) medulla of the rat kidney immediately after 60 min of ischaemia followed by varying periods of reperfusion. Ischaemia of the left kidney caused HSP25 contents to decrease in CX, OM and IM by 73, 89 and 54% respectively, compared with the corresponding zones of the contralateral control kidney. This initial decrease in supernatant HSP25 was accompanied by an increased abundance of HSP25 in the pellet. Following reperfusion, HSP25 contents in the supernatant gradually increased in CX and OM, reaching, after 24 h, values that were 5.4- and 2.5-fold higher, respectively, than those in the control kidneys. After 7 or 14 days of reperfusion, HSP25 contents had not completely normalised in CX, but had reached control levels in OM. In IM, the HSP25 content remained below control throughout the entire reperfusion period. HSP72 (supernatant) was below the detection limit in the CX of the control kidney. Similar to the level of HSP25, that of HSP72 was also markedly lower in OM and IM immediately after ischaemia. The intrarenal distribution of HSP72 and the sequence of zonal changes in HSP72 contents were similar to those observed for HSP25. These results are compatible with the view that, during ischaemia and the initial reperfusion period, HSP25 migrates from the cytoplasmic compartment (supernatant) into the nucleus and/or associates with cytoskeletal structures. The observation that both HSP25 and HSP72 are transiently induced in CX and OM, but not in IM, may be explained by the fact that, while all kidney cells are exposed to ischaemic stress, only inner medullary cells experience a major postischaemic attenuation of osmotic stress. Received: 11 February 1997 / Received after revision and accepted: 26 March 1997  相似文献   
22.
Caspase inhibitor Z-VAD-FMK potentiated heat shock-induced apoptosis in macrophages. Z-VAD-FMK did not activate HSP70 synthesis, but significantly increased the intensity of this process during heat shock. It cannot be excluded that caspases abolish HSP70 accumulation under these conditions. The HSP70 synthesis inhibitor quercetin potentiated DNA fragmentation in macrophages cocultured with Z-VAD-FMK after heat shock. HSP70 play an important role in the protection of macrophages from caspase-independent apoptosis.Translated from Byulleten Eksperimentalnoi Biologii i Meditsiny, Vol. 138, No. 9, pp. 261–263, September, 2004  相似文献   
23.
目的:检测急性白血病病人血淋巴细胞热休克蛋白70(HSP70)及其mRNA的表达。方法:ELISA法检测HSP70,RT-PCR法检测HSP70 mRNA。结果:化疗前急性白血病病人淋巴细胞HSP70及mRNA明显低于正常人;而化疗后,急性白血病病人淋巴细胞HSP70及mRNA明显高于正常人(P<0.01),结论:HSP70与急性白血病癌细胞关系密切,对癌细胞起保护作用。  相似文献   
24.
目的 :研究热休克预处理对脑缺血再灌后热休克蛋白 70 (HSP70 )的表达影响及对缺血神经细胞损伤的保护作用。方法 :采用沙鼠短暂前脑缺血再灌损伤模型 ,光镜观察缺血再灌后神经细胞损伤情况 ,免疫组化方法检测脑缺血后不同时期额叶HSP70蛋白表达。结果 :沙鼠脑缺血后HSP70蛋白仅在再灌后 1d有少量表达 (P <0 .0 1) ;缺血神经细胞在再灌后第 7d大多出现损伤改变 ;热休克预处理能增加沙鼠脑缺血再灌后各期HSP70蛋白表达 (P <0 .0 1) ,明显减轻缺血神经细胞损伤 (P <0 .0 1)。结论 :热休克预处理能通过增加HSP70蛋白表达 ,减少缺血神经细胞损伤。  相似文献   
25.
肿瘤标志物DR-70在恶性肿瘤诊断中的应用   总被引:1,自引:0,他引:1  
林丁  沈萍  杨静梅 《重庆医学》1999,28(5):332-333
目的:评价肿瘤标志物DR-70在恶性肿瘤中的诊断应用。方法:应用美国AMDL公司的DR-70^TM ELISA试剂盒,测定对20例正常人和59例恶性肿瘤病人血清DR-70含量。结果:各种恶性肿瘤DR-70的阳性率为66.7 ̄100%,均较正常对照组有非常显著性差异(P〈0.001)。结论:血清DR-70是诊断恶性肿瘤有价值的标志物。  相似文献   
26.
Summary The neuropathological findings in a Japanese male with nephrosialidosis are reported. Clinically, coarse face, psychomotor retardation, macular cherryred spot and proteinuria were noted at 1 year and 7 months. He was diagnosed to have nephrosialidosis on the basis of a deficiency of -neuraminidase activity in both lymphocytes and cultured skin fibroblasts, and of severe glomerular and tubular involvement on renal biopsy. He died of multiple organ failure at 8 years and 6 months. There were numerous vacuoles and storage materials in visceral organs, particularly in the glomerular and tubular epithelial cells of the kidney and Kupffer cells as well as hepatocytes in the liver. Neuropathological examination revealed severe neuronal storage in the selected part of the central nervous system; lower motor neurons of the brain stem and spinal anterior horn cells, as well as neurons in the basal nucleus of Meynert. In the peripheral nervous system, sympathetic ganglia were severely affected. There was little or no neuronal storage in the basal ganglia, cerebral cortex or cerebellum, and demyelination was not found. Electron microscopic examination showed fine wavy multilamellar structures in the spinal anterior horn cells or Zebra body-like structures in the neurons of the Meynert's basal nucleus. Lectin histochemistry was positive for wheat germ agglutinin, Ricinus communis agglutinin-1 and peanut agglutinin within distended neurons. We conclude that the neuropathological feature in nephrosialidosis is not specific except for the selectiveness of the anatomical sites of involvement. It shares some aspects found in other types of sialidosis or galactosialidosis.  相似文献   
27.
Summary The pharmacokinetics of ANP-270, a 26 amino acid analogue of alpha human natriuretic factor (-hANF) with a prolonged effect on isolated arterial preparations has been studied in 40 healthy males, in a doubleblind placebo controlled investigation. Placebo or ANP-270 0.3, 1.5 or 3.0 g/kg were given by intravenous bolus injection, each to groups of 10 subjects. Blood samples were assayed for ANP-270 by a specific sandwich ELISA.The disappearance of ANP-270 from plasma followed a two-compartment decay, with mean distribution and elimination half-lives of 2.6 min (n = 30) and 10.6 min (n=20), respectively. These estimates were similar to those obtained by other investigators for -hANF. Their brevity explains the lack of a prolonged effect of ANP-270 in vivo compared to -hANF.  相似文献   
28.
HSP70的肿瘤免疫作用及其基因表达调节   总被引:4,自引:0,他引:4  
热休克蛋白70能够与肿瘤特异性抗原多肽结合,形成热休克蛋白70-多肽复合物,它本身没有抗原性,其抗原性由它结合的多肽所决定,而它是作为"分子伴侣"参与肿瘤免疫作用过程.将这一特性加以应用,可能为肿瘤的治疗和消灭开辟新的途径.  相似文献   
29.
MRP-1/CD9和HSP60在膀胱癌中的表达   总被引:2,自引:0,他引:2  
目的:探讨MRP-1/CD9和HSP60的表达与膀胱癌发生发展的关系.方法:应用免疫组织化学技术(SP法)检测CD9和HSP60在75例膀胱移行细胞癌标本,15例正常膀胱组织中的表达.结果:CD9和HSP60在正常膀胱组织均高表达,41.2%和42.7%的膀胱癌对CD9和HSP60显示了表达减低.不同临床分期和病理分级的膀胱癌中CD9的表达有差异(P<0.05),根据预后表浅性膀胱癌的复发浸润组和非浸润组中CD9和HSP60表达有差异(P<0.05).结论:CD9和HSP60可能与膀胱癌的发生发展有关,它们可能作为判断膀胱癌预后的新指标.  相似文献   
30.
热休克对人胶质瘤热休克蛋白70表达水平的影响   总被引:1,自引:0,他引:1  
目的:应用热休克人胶质瘤细胞的方法,观察热诱导热休克蛋白70(heatshockprotein70,HSP70)在人胶质瘤细胞的表达。方法:经43℃热处理2h的人胶质瘤细胞,应用半定量逆转录聚合酶链反应(RTPCR)及免疫组化技术检测HSP70mRNA及蛋白的表达情况。结果:热休克蛋白人胶质瘤细胞表达阳性率为(39.40±14.40)%,对照组为(8.50±4.60)%及HSP70mRNA表达光密度值为0.23±0.05,对照组为0.13±0.03与内参照βactin比值经单因素方差分析q检验显示与对照组相比有明显的升高。结论:热休克的方法可以明显诱导人胶质瘤细胞HSP70的表达。  相似文献   
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