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31.
Mass screening for hepatitis C virus antibody was carried out in 875 inhabitants (313 men and 562 women) of a town in Japan with a high rate of hepatitis B virus infection. The overall rate of positivity for anti-HCV was 8.8% (6.4% in men and 10,1% in women). The rate of positivity for hepatitis B virus surface antigen was 11.2%. Five subjects (0.6%) were positive for both markers. HCV-RNA was detected in 65 (88.4%) of 77 individuals who were positive for anti-HCV and in 1 (1.5%) of 60 individuals negative for anti-HCV. The genotype of the HCV genome was determined by PCR analysis using type-specific primers in 60 individuals. HCV type 1b was detected in 51 subjects (85%), type 2a in 3 subjects (5%), and type 2b in 6 subjects (10%). None of the individuals was infected with more than one genotype. The nucleotide sequences of the partial nonstructural 5 region of HCV type 1b genotype obtained from 6 individuals showed at least 92.0% homology in the nucleotide sequence, and 94.8% homology in the amino acid sequence. Homology among these clones was greater than their homology with previously described type 1 b sequences. The findings suggest that there was a specific local origin of HCV infection, although it was not possible to identify any single source of HCV infection. The results also indicate the presence of asymptomatic HCV carriers. © 1995 Wiley-Liss, Inc.  相似文献   
32.
逆转录病毒载体介导乙型肝炎病毒反义基因的转录表达   总被引:2,自引:0,他引:2  
为了探索在真核细胞内转录表达乙型肝炎病毒(HBV)反义核酸的方法,用基因重组技术将HBV前C/C基因(PreC/C)和前S/S基因(PreS/S)片段反向插入逆转录病毒载体质粒,再将重组体分别转染PA317包装细胞,进而获得能够介导HBV反义基因向小鼠NIH3T3细胞转移表达的重组逆转录病毒。经分子杂交试验表明,含有HBV反义基因的重组逆转录病毒序列已经整合到转染的PA317细胞染色体上;转导的NIH3T3细胞内有HBV反义RNA转录表达。结论:逆转录病毒载体包装细胞系统能够介导HBV反义基因在真核细胞中转录表达,因而有可能利用反义技术和基因转移方法进行抗-HBV基因治疗  相似文献   
33.
NF-κB在人肝细胞肝癌中的表达及与HBV X蛋白的关系   总被引:2,自引:0,他引:2  
目的:研究核转录因子NF--κB在人肝细胞肝癌组织中的表达及其与乙型肝炎病毒(HBV )X蛋白的关系。方法;用免疫组织化学S-P法,检测52例人肝细胞肝癌组织中核转录因子NF--κB及HBV X蛋白的表达;用脂质体介导的基因转染法将HBV x基因真核表达载体pcDNA3.1-HBX转染入人肝癌细胞系HCC-9204,检测肝癌细胞内核转录因子NF--κB的表达。结果:52例人肝细胞肝癌组织均有核转录因子NF--κB的广泛表达,并且在11例HBV X蛋白阳性的肝癌组织,核转录因子NF--κB位于细胞胞质和胞核,而在41例HBV X蛋白阴性的肝癌组织,核转录因子NF--κB位于肝癌细胞的胞质。将HBV x基因真核表达载体pcDNA3.1-HBX转染 入人肝癌细胞系HCC-9204,并在稳定表达X蛋白 的肝癌细胞,核转录因子NF--κB定位于其胞质和胞核,而未进行基因转染的亲体细胞,核转录因子NF--κB仅定位于细胞质,细胞核无核转录因子NF--κB的表达。结论:核转录因子NF--κB在人肝细胞肝癌组织中广泛表达,人肝细胞肝癌中存在着核转录因子NF--κB的异常激活,并且核转录因子NF--κB的异常激活与HBV X蛋白有关,X蛋白激活核转录因子NF--κB, 使其从细胞转位于细胞核,这可能在HBV相关的人原发性肝癌肝癌的发生中起一定作用。  相似文献   
34.
The long-term efficacy of lamivudine therapy in patients with hepatitis B virus (HBV) infection is still not clear. In this study, 20 non-cirrhotic Japanese patients infected with HBV received lamivudine therapy for more than 1 year and were followed for a median period of 8.5 years (range, 6.7-8.7 years). The rates of HBe antigen (HbeAg) negative, HBV-DNA undetectable, and alanine aminotransferase (ALT) normal level at the start of lamivudine were 55%, 25%, and 20% and 85%, 80%, and were 80%, respectively, at the last visit, including patients who received additional treatment. The values at the last visit tended to and were significantly higher than those at the start. The values improved at the last visit regardless of the emergence of YMDD motif mutant and continuation of lamivudine. YMDD mutant and biochemical relapse with mutant virus (breakthrough hepatitis) appeared in 65% and 45% during follow-up, respectively, but severe breakthrough hepatitis occurred in only 5%. Furthermore, 80% of patients who received additional treatment for breakthrough hepatitis, regardless of continuation of lamivudine, were ALT normal level at the last visit, in contrast to 25% untreated. HBsAg clearance occurred in two patients of the discontinuous lamivudine group with non-vertical transmission, who were relatively young. One was infected with HBV genotype C with breakthrough hepatitis and the other had no YMDD mutant and was infected with genotype D, a rare type in Japan. None developed cirrhosis or hepatocellular carcinoma (HCC) during follow-up. Our results suggest that long-term lamivudine therapy improves long-term prognosis, especially when additional treatment for breakthrough hepatitis is used.  相似文献   
35.
目的分析人类免疫缺陷病毒(HIV)感染者中合并乙型肝炎病毒(HBV)、丙型肝炎病毒(HCV)以及梅毒螺旋体(TP)感染的流行现状及其特点。方法对确诊的184例HIV感染者进行流行病学调查,并采集血标本进行HBV、HCV和梅毒血清学检测。结果HIV感染者感染途径分别为:静脉注射毒品44.0%,性传播20.1%,母婴传播4.3%,输血或血制品3.8%,其他(原因不详)27.7%。184例HIV感染者中,抗-HCV阳性者36人(19.6%),HBsAg阳性者29人(15.8%),梅毒感染者21人(11.4%)。HIV、HBV和HCV三重感染者9人,约占4.9%。结论柳州市HIV感染以静脉注射毒品为主,性传播有所上升,HIV感染正由特殊人群向普通人群蔓延。HIV合并HBV、HCV、TP感染较为常见。建议在性病门诊中常规开展HIV的筛查,对HIV感染者常规进行HBV、HCV的相关检查并积极采取相关的预防治疗措施。  相似文献   
36.
Several reports show that the prevalence of HBV (hepatitis B virus) carriers in HIV (human immunodeficiency virus) infected populations is significantly higher than in HIV seronegative individuals, independent of the risk group for HIV, that is, homosexuals or drug abusers. In this context, evaluation of the simultaneous presence of HBV and HIV in PBMCs (peripheral blood monuclear cells) is of particular interest for at least 2 reasons: 1) the possible reciprocal influence of the 2 viruses when they infect the same cell; 2) the possibility that HIV-iduced hematological disorders could indirectly influence the settling of HBV in blood cell populations. We report data on the frequency of PCR positivity for HBV DNA in PBMCs from 62 HIV infected patients, rigorously selected by risk group, that is, intravenous use of heroin for at least 3 years and syringe promiscuity. Sixtyseven HIV negative individuals who never used any drug formed the control group. The analysis of the cases positive for HBV DNA in PBMCs showed that 1) the overall prevalence of PCR positivity found in HIV infected patients was significantly lower than that registered in the control group; 2) PCR positivity among the subjects who were HBsAg negative and anti-HBV positive was extremely low in the HIV infected patients (3.7%) but quite frequent in the HIV negative subjects (37.0%). The results support the hypothesis that, unlike the HIV negative individuals, our HIV infected patients exhibited HBV DNA in PBMCS almost exclusively when they presented with active HBV replication.  相似文献   
37.
The amplification of hepatitis B virus (HBV) DNA sequences in sera for molecular epidemiology of HBV is an important application of the polymerase chain reaction (PCR) with regard to HBV. To simplify the PCR for this purpose, the optimal concentrations of SDS and detergents for carrying out the proteinase K digestion and the amplification of DNA by Taq polymerase were evaluated. It was found that by using 1% deoxycholic acid as detergent for the proteinase K step and diluting the digest 10 times before carrying out the PCR, the phenol extraction of DNA became superfluous. The sensitivity of this procedure equalled that of PCR after phenol extraction on comparable amounts of serum. Four pairs of oligonucleotide primers were compared for amplification of HBV DNA sequences in 48 sera previously subtyped with respect to hepatitis B surface antigen (HBsAg), and in eight sera with different genotypes of HBV, representing the subtypes of HBsAg P1 to P8, defined at an international meeting [Couroucé-Pauty et al.: "HBs Antigen Subtypes." Basel: Karger, 1976]. Two primer pairs, selected from conserved regions in the X and S genes of HBV, gave a positive PCR with sera harbouring all the eight different strains of HBV, resulting in DNA fragments consistent with the sizes deduced from genome sequence data. Two other primer pairs were selected in order to discriminate genotypes with regard to differences between d/y and w/r strains.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
38.
Reactivation of hepatitis B e antigen (HBeAg) negative chronic hepatitis B virus (HBV) infection due to selection of precore variant virus is an uncommon complication of previous hepatitis B infection, and virtually unrecognised in children and adolescents. A child who had received treatment with methylprednisolone and antilymphocyte globulin for severe aplastic anaemia developed high levels of detectable HBV DNA associated with hepatitis B e antibody (anti-HBe) positivity. HBV DNA was extracted, amplified and the core and precore regions sequenced from 2 samples. A mixture of wild-type and the precore variants A(1896) and A(1899) was detected in both samples, with the wild-type predominating in the second sample. Reinfection was excluded by phylogenetic analysis using Phylip and the neighbour-joining method. Precore variant Hepatitis B virus can be transmitted to children as a primary infection, and it is important that aggressive liver disease, particularly in the presence of the anti-HBe phenotype, be investigated. Further studies are needed to determine the frequency of these variants.  相似文献   
39.
 异基因造血干细胞移植(allo-HSCT)是治愈恶性血液病的有效手段,但移植患者因接受感染乙型肝炎病毒(HBV)的移植物、免疫功能严重受损等原因,术后并发乙型病毒性肝炎的风险增加。恩替卡韦和替诺福韦是目前公认用于预防allo-HSCT后乙型病毒性肝炎的有效药物,显著减少移植后患者的肝损伤。移植后患者的免疫重建时间长且重建规律存在异质性,导致术后监测和预防性抗HBV治疗的最佳持续时间尚未能明确。本文对allo-HSCT后HBV再激活的发生机制、乙型病毒性肝炎的特点及防治的最新研究进展进行综述。  相似文献   
40.
乙型肝炎病毒相关肾炎临床与病毒血清学特点关联研究   总被引:9,自引:0,他引:9  
目的 研究乙型肝炎病毒(HBV)感染与肾小球肾炎的关系,探讨HBV复制在HBV相关肾炎发病中的作用。方法 对338例经肾穿刺证实的肾炎患者的临床病理和病毒血清学特点进行分析。结果 HBV相关肾炎占肾炎总数的5.3%。在血HBsAg( )的肾炎患者中,HBV相关肾炎发病与HBeAg相关(P<0.05),与血清HBV DNA含量(bDNA)显著相关(P<0.01)。分支链DNA(bDNA)阳性率明显高于HBeAg阳性率(P<0.05)。结论 bDNA是反映HBV复制的最佳指标。HBV相关肾炎与体内HBV复制程度密切相关,HBV在体内大量复制,可能通过循环中的病毒抗原沉积于肾脏和肾脏中该抗原原位表达而致病。  相似文献   
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