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71.
P53基因突变与宫颈癌关系的研究 总被引:1,自引:0,他引:1
目的:通过对宫颈癌P53基因7-8外显子突变的研究,探讨该基因的突变与宫颈癌的发生、发展之间的关系。方法:本文运用聚合酶链式反应(PCR)方法,对宫颈癌组织P53的7-8外显子是突变进行了试验,并与非肿瘤的慢性宫颈炎(宫颈糜烂、宫颈息肉)组织作了对照。结果:10例宫颈癌标本中有7例出现了P537-8外显子的突变,阳性率高;而8例作为对照的宫颈炎标本仅有1例出现可疑的阳性结果。结果:试验结果说明,宫 相似文献
72.
目的:寻找适合于临床PCR检测结核杆菌DNA简单、快速、有效、经济的细菌裂解方法。方法:采用11种细菌裂解剂对相同数量的结核分枝杆菌进行裂解,裂解上清液直接用于PCR扩增,结果:1%TritonX-100,1%NP40,1%Teween20、和1%OP四种裂解剂的裂解液可直接扩增出结核分枝杆菌DNA;SDS,NaOH,十二烷基肌酸钠等裂解剂的裂解液直接用于PCR扩增均为阴性。结论:1%的Tritonx-100,NP40、Teween20和乳化剂OP裂解细菌效果好,又不抑制PCR反应,适合于作为临床PCR检测结核杆菌的裂解剂。 相似文献
73.
聚合酶链反应在鼠疫菌检测中的应用 研究 总被引:2,自引:0,他引:2
本文采用聚合酶链反应(PCR)技术,通过扩增鼠疫菌9.5kb质粒pla基础上一个478bl片段,用于鼠疫菌检测,被试的45株鼠疫菌扩增产物经琼脂糖凝胶电泳分析均呈现单一DNA带,其分子量大小与预期结果符合。而假结核菌和一株缺6MD质粒鼠疫菌未见扩增带,洽部实验可在4h内完成。本法具有快速、特异、敏感等优点,可用于不同生态型鼠疫菌的快速诊断和流行病学研究. 相似文献
74.
Clinical and diagnostic DNA laboratories must maintain a large inventory of DNA probes for use in hybridization studies. The preparation of plasmid DNA and isolation of DNA fragments for use as probes in both expensive and time consuming. We present here a rapid and relatively inexpensive method of producing large amounts of DNA fragments from stocks, using the polymerase chain reaction (PCR). Our experience over the past year using this technique has been very positive and we believe many laboratories could benefit by employing such a labor-saving approach to maintaining DNA probes. The technique uses the bacteriophage M13 DNA sequencing primers to amplify cloned inserts contained in commonly used plasmid vectors. As examples, we illustrate the use of DNA produced in this manner as probes for linkage analysis of the fragile X syndrome and for detection of deletions in the Duchenne muscular dystrophy gene. We have also found that at least two probes can be amplified in the same PCR reaction, allowing the detection of two different restriction fragment length polymorphisms (RFLP) simultaneously. It should be possible for laboratories to devise strategies particular to their individual needs using more than one DNA probe produced in the same PCR reaction to detect RFLP's. Such strategies would need only to consider that the predicted alleles of the multiple polymorphisms do not migrate to the same position during electrophoresis. Stocks of single or multiple probes produced by the PCR could then be maintained for more rapid Southern analyses. 相似文献
75.
尖锐湿疣患者人乳头瘤病毒的基因分型 总被引:2,自引:0,他引:2
目的 探索尖锐湿疣患者人乳头瘤病毒的基因分型。方法 PCR方法检测HPV6/11型、HPV16/18型DNA。结果 检测尖锐湿疣患者100例,对其中35例进行组织活检,阳性检出率为91.4%(32/35),阳性检出中,HPV6/11型26例(81.2%),HPV16/18型3例(9.4%),HPV6/11 HPV16/18型3例(9.4%);对其中65例进行宫颈抹片检测,阳性检出率为92.3%(60/65),阳性检出中,HPV6/11型41例(68.3%),HPV16/18型12例(20.0%),HPV6/11 HPV16/18型7例(11.7%)。结论 尖锐湿疣患者人乳头瘤病毒感染以HPV6/11型为主,HPV16/18型在宫颈处感染率高于其它处组织。 相似文献
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Abstract: The fate of polymorphonuclear neutrophilic granulocytes (PMN) after their mobilization from the bone marrow of healthy individuals is not clearly understood. It has been suggested that there is a continuous utilization of these cells in widespread, subclinical inflammatory foci, where they are ultimately degraded. The goal of the present experiments was to determine whether an alternative ecotaxis (“homing”) exists, namely sequestration and degradation of PMN by mononuclear phagocytes exposed to the bloodstream in the liver, spleen and bone marrow. Blood PMN were collected from donor rats, labelled with 51Cr, and injected i.v. into 2 syngeneic rats, one of them having an induced sterile peritonitis. After various time intervals up to 18 h, the rats were killed and exsanguinated. As expected, we found cell-bound radioactivity in the inflamed peritoneal cavities, and also a high amount of radioactivity in liver, spleen, and bone marrow. The bone marrow uptake of PMN appeared to be much lower in the inflammation rats than in the normal controls. These findings were confirmed in PMN transfer experiments using PVG rats congenic for the RT7 alloantigenic system. Here, transfused blood leukocytes were traced with fluorescent, monoclonal HIS41 antibodies and flow cytometry. A possible corticosteroid effect on the bone marrow sequestration could not be substantiated. Uptake and degradation of PMN takes place in organs containing phagocytes exposed to the bloodstream. Sequestration of PMN in the bone marrow is apparently down-regulated in inflammatory states, perhaps increasing the PMN availability to inflamed tissue. 相似文献
79.
检测25例脑肿瘤中抑制癌基因P53突变情况。突用复合PCR,聚合酶链反应-=单链构象多态性分析法,统计学处理采用X^2检验。结果:P53基因总的突变率为44.0%,其中第5外显子突变率为28.0%,第6外显子突变率12.0%,第7外显子突变率为12.0%,第8外显子突变率16.0%;病理分级Ⅱ级及其以上突变为72.7%, 相似文献
80.
Virological, biochemical and histological effects of human lymphoblastoid interferon in Swedish patients with chronic hepatitis C 总被引:1,自引:0,他引:1
J. A. Garson I. Uhnoo K. Whitby J. H. Braconier R. Deaville A. Duberg E. Wallmark J. Wiström R. D. Goldin B. Spacey 《Journal of viral hepatitis》1997,4(5):325-331
Thirty-eight Swedish patients with chronic hepatitis C were randomly assigned to receive either 3 million units (MU) or 5MU of human lymphoblastoid interferon-α-n1 (Wellferon) three times per week for either 6 or 12 months. The patients were monitored biochemically, histologically and by quantitative polymerase chain reaction for circulating HCV RNA, during therapy and for the following year. Overall, 22 (58%) of the patients lost detectable hepatitis C virus (HCV) viraemia during therapy but eight of these patients relapsed during follow-up, leaving 14 (37%) sustained responders. Patients infected with HCV non-type 1 genotypes were significantly more likely to achieve a sustained response than were those infected with HCV type 1 (63% vs 10.5%, P =0.001). Sustained virological responses were also associated with lower pretreatment viraemia level, younger age, absence of cirrhosis and the higher interferon dosage regimens but these associations failed to reach statistical significance. In 97% of patients there was concordance between virological and biochemical responses, and a statistically significant ( P =0.005) improvement in the Knodell histological activity index was observed in the virological sustained responders. 相似文献