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101.
102.
人肿瘤细胞TH2类细胞因子的逆转与NK抗性变化的研究 总被引:3,自引:0,他引:3
目的研究促使人肿瘤细胞中TH2类细胞因子表达向TH0型的逆转及逆转后的肿瘤细胞对NK抗性的变化。方法首先用MTT方法对悬浮培养的肿瘤细胞株DB大淋巴细胞瘤、Karpas淋巴瘤、Michael淋巴瘤、Raji、HL60和K562进行了NK杀伤敏感性的筛选。选择NK不敏感的Karpas淋巴瘤和HL60,用rhIFNγ、rhIL-12和抗IL-10McAb经不同组合对其进行由TH2类细胞因子表达向TH1类细胞因子表达的促逆转研究,并观察促逆转后的肿瘤细胞对NK抗性的变化。结果RT-PCR结果表明,经上述不同细胞因子组合诱导后,Karpas淋巴瘤细胞均从表达TH2类细胞因子为主向TH0型逆转,并且各组逆转后的肿瘤细胞对NK的抗性均有不同程度的减弱。结论TH1类细胞因子(如IFNγ)、TH2类细胞因子拮抗剂(如IL-10单抗)和IL-12不同程度地促进肿瘤细胞表达的细胞因子由TH2型向TH0/TH1型逆转。促逆转后可以改善肿瘤细胞对机体杀伤作用的敏感性,提高抗肿瘤免疫能力 相似文献
103.
Elisabeth Puchhammer-Stckl Wolfgang Mor Michael Kundi Franz-Xaver Heinz Hanns Hofmann Christian Kunz 《Journal of medical virology》1994,43(2):143-147
Serum samples from 46 children with chronic and probably transfusion acquired hepatitis were tested for the presence of hepatitis C virus (HCV) RNA by a “nested” polymerase chain reaction (PCR) assay, to judge a possible risk of HCV transmission from these patients. In 73% of the samples, viral RNA was detected, indicating a high virus prevalence in this patient group. High titers of HCV-RNA were observed in some sera as shown by the detection of virus in some samples even at dilutions of 10?3. Comparison of simultaneously obtained PCR results and ALT values revealed no significant correlation between virus presence in serum and higher ALT levels. It was, however, shown that unusually high ALT values may reflect a high titer of viral RNA in serum. To investigate the prevalence of viral RNA in saliva, which could be a vehicle of virus transmission, 35 throat washing samples from the HCV-infected children were screened by PCR. Using three different sample preparation procedures, 20% of the throat washings were found to be positive for HCV-RNA. This indicates a prevalence of virus in this fluid lower than that reported previously. © 1994 Wiley-Liss, Inc. 相似文献
104.
采用套式聚合酶链反应结合变性聚丙烯酰胺凝胶电泳和银染技术,并构建载脂蛋白CII(ApoCII)基因二核苷酸串联重复序列(TG)n(AG)m及(AG)m序列等位基因梯阶标准;检测正常汉族人群基因型和等位基因频率分布,检出36种(TG)n(AG)m序列基因型、12种等位基因。等位基因为17、18、26-35,其频率分别为0.061、0.011、0.002、0.002、0.054、0.255、0.372、0.084、0.026、0.039、0.052、0.041。检出7种(AG)m序列基因型、4种等位基因。等位基因为6、7、8、9,其频率分别为0.002、0.152、0.812、0.034。与欧洲白种人比较,ApoCII基因二核苷酸串联重复序列(TG)n(AG)m及(AG)m序列等位基因频率分布均具有明显的种族差异性(P<0.01,P<0.01)。 相似文献
105.
106.
E. V. Pulyaeva A. L. Konorova L. I. Kovalev A. Yu. Volgin S. S. Shishkin L. A. Pevnitskii 《Bulletin of experimental biology and medicine》1991,112(4):1483-1485
Research Institute of Human Genetics, All-Union Medical Genetics Research Center, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. D. Ado.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 112, No. 10, pp. 416–417, October, 1991. 相似文献
107.
Detection of DNA from infectious laryngotracheitis virus by colourimetric analyses of polymerase chain reactions 总被引:3,自引:0,他引:3
A combination of the polymerase chain reaction and a novel ELISA-type DNA colourimetric assay (developed from studies with a retrovirus from man) was used in a preliminary study to detect DNA from avian infectious laryngotracheitis virus. The method is sensitive, specific and easy to perform. Since it can be readily adapted for the detection of DNA from other sources it could be useful for the identification of a variety of pathogens from other species of veterinary importance. 相似文献
108.
J A Garson M Lenzi C Ring F Cassani G Ballardini M Briggs R S Tedder F B Bianchi 《Journal of medical virology》1991,34(4):223-226
Sera from 14 patients with type 2 autoimmune hepatitis (anti-LKM1 positive) were investigated for evidence of hepatitis C virus (HCV) infection. Antibodies to HCV were detected in 13 patients by both commercial and "in-house" ELISAs and also by a second generation recombinant immunoblot assay. Nine of the 13 (69%) anti-HCV positive patients were shown to be viraemic by a polymerase chain reaction-based assay for serum HCV RNA. Neither anti-HCV nor serum HCV RNA were detected in any of 6 controls with primary biliary cirrhosis or in 39 healthy blood donors. These findings strongly suggest a role for HCV in the pathogenesis of type 2 autoimmune hepatitis. 相似文献
109.
应用PCR技术检测恙螨体内恙虫病立克次体动态和经卵传递的研究 总被引:7,自引:0,他引:7
本文应用聚合酶链反应技术检测恙虫病立克次体实验感染的恙螨体内立克次体的动态变化,通过人工腹腔接种而感染的恙螨成虫,恙虫病立克次体至少能在其体内生存360天和经卵传递4代;通过未食幼虫叮咬病小鼠而感染的恙螨,经饱蚴、若蛹、若虫、成蛹和成虫阶段,恙虫病立克次体检测均呈阳性,至少能在成虫期体内生存270天和经卵传递1代。 相似文献
110.
Following second-trimester twin amniocentesis, we used quantitative fluorescent polymerase chain reaction (QF-PCR) assays and polymorphic small tandem repeats (STR) for rapid determination of zygosity and common aneuploidies from amniotic fluid (AF) cells in four pregnancies with like-sex twins, fused placentae and inconclusive chorionicity. The first and the second cases were suspected to have inadvertent sampling of the same amniotic cavity twice. The first case showed a dizygotic (DZ) pattern and repeat amniocentesis was thus avoided. The second case was monozygotic (MZ) and was complicated by discordant fetal growth and twin-twin transfusion syndrome. The third case was associated with a co-twin malformation, occipital encephalocele. DNA studies revealed MZ twinning with a discordant structural defect. The fourth case was associated with co-twin abnormalities of cystic hygroma and hydrops fetalis. DNA studies showed DZ twinning with discordant structural and chromosomal defects. The QF-PCR assay with STR has the advantages of rapid determination of zygosity and common aneuploidies in AF cells. This simple test appears to be useful in the instances of possible inadvertent puncture of the same amniotic cavity twice during amniocentesis and of discordant fetal structural and/or chromosomal abnormalities following genetic amniocentesis in multiple pregnancies with uncertain chorionicity. 相似文献