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101.
浙江省在鼠中检测到埃立克体及无形体DNA片段并测序分析 总被引:1,自引:0,他引:1
目的:了解鼠中自然感染埃立克体及无形体的状况。方法:用巢式PCR扩增鼠中埃立克体属及嗜粒细胞无形体属16S rDNA的5′末端片段,对阳性产物克隆后测序。结果:在浙江省金华市金东区捕到鼠128只。在黄毛鼠中检到阳性4份,阳性率为3.125%,并对其进行克隆后测序。与Genbank上比对分析,三份与牛埃立克体相同基因区最为接近,属无形体科,无形体属。一份与反刍动物埃立克体相同基因区最为接近,属无形体科,埃立克体属。均为国内首次报道。结论:初步认为浙江省存在埃立克体及无形体病原。黄毛鼠可能为埃立克体及无形体宿主,尚需进一步调查。 相似文献
102.
Pierre Boudinot Dominique Rueff-Juy Anne-Marie Drapier Pierre-Andr Cazenave Pierre Sanchez 《European journal of immunology》1995,25(9):2499-2505
The diversity of the B cell repertoire of Cx knockout mice is limited by the expression of four λ light chain types. Among the spleen B cells, λ1 is expressed by the majority (58%) of cells, and λ3 by the minority (8%), while λ2(V2) and λ2(Vx) are expressed in intermediate quantities (18% and 16%, respectively). To assess the influence of mechanistic pressures on the λ subtype distribution, the proportions of the different λ rearrangements were determined in various B cell subpopulations divided on the basis of the λ subtype expressed, and the VλJλ junction sequences were studied at different steps of B cell differentiation (pre-B, immature and mature B cells). The data show that (1) the ratio of productive/non-productive VJ junctions is determined by the nature of the λ segments that are rearranged as can be observed in the pre-B cells, (2) V1-J1 non-productive rearrangements are often found in the λ1-negative B cells in the periphery, and (3) V1J3 junctions are often non-productive regardless of the nature of the cells analyzed. Our results, therefore, suggest that a strong probability of initiating a V1-J1 rearrangement and a weak probability of giving a productive V1J3 junction are responsible for the λ1 dominance and the λ3 under-expression, respectively. The intermediate proportion of λ2(V2) subtype is most likely due to a probability of obtaining a productive joint that is better than that for V1J3 and a probability of initiating a rearrangement that is lower than that for V1J1. However, the λ2(Vx) cell proportion cannot be determined only by these parameters. 相似文献
103.
Antonella d’Arminio Monforte Paola Cinque Luca Vago Aleandro Rocca Antonella Castagna Cristina Gervasoni Maria Rosa Terreni Roberto Novati Andrea Gori Adriano Lazzarin Mauro Moroni 《Journal of neurology》1996,244(1):35-39
Twenty patients with AIDS who had intracranial lesions underwent both brain biopsy and cerebro-spinal fluid (CSF) examination
to compare histological diagnosis with the polymerase chain reaction (CSF-PCR) for the identification of infectious agents.
CSF-PCR was performed for herpes simplex virus, varicella zoster virus, cytomegalovirus (CMV), JC virus (JCV), Epstein-Barr
virus (EBV), Toxoplasma gondii and Mycobacterium tuberculosis. A definitive diagnosis was obtained by brain biopsy in 14 patients (2 with astrocytoma, 12 with brain infection). CSF-PCR
was positive for EBV DNA in 3 of 3 cases of primary cerebral lymphoma, positive for JCV DNA in 6 of 7 biopsy-proven (and one
autopsy-proven) cases of progressive multifocal leukoencephalopathy (PML). CSF-PCR was positive for CMV DNA in one biopsy-proven
and one autopsy-proven case of CMV encephalitis (the former also had PML) and positive for M. tuberculosis DNA in one case of tuberculous encephalitis. None of the five toxoplasmic encephalitis cases (one definite, four presumptive)
were T. gondii DNA positive. There was close correlation between histology and CSF-PCR for CMV encephalitis, PML and PCL. Antitoxoplasma
therapy affected the sensitivity of both histological and CSF-PCR methods.
Received: 8 November 1995 Received in revised form: 9 July 1996 Accepted: 19 July 1996 相似文献
104.
AmpliSensor-聚合酶链反应技术检测结核分支杆菌及临床应用 总被引:14,自引:3,他引:11
目的探讨Amplisensor-聚合酶链反应(AmpliSensor-PCR)在结核病诊断中的价值。方法采用AmpliSensor-PCR对784例结核病患者及160例肺癌患者的标本进行检测,并与PCR(凝胶电泳后,经溴化乙锭染色)、涂片、培养等法比较。结果AmpliSensor-PCR的敏感性显著高于涂片及培养(P<0.01)。特异性较PCR法高。结论AmpliSensor-PCR可以通过标准曲线划定检出下限,并可换算出标本中原始的靶DNA值,同时具有较高的特异性和敏感性,对肺结核尤其是肺外结核的诊断有一定的临床意义。 相似文献
105.
链置换式扩增检测羊水中巨细胞病毒DNA 总被引:2,自引:1,他引:1
目的:介绍一种简便快速准确检测羊水中CMV-DNA的改良PCR-链置换式扩增用于诊断胎儿先天感染CMV。方法,将组成套式PCR的外内两对引物按照一定比例(外:内=1:50-100)加在同一试管中一次扩增羊水和胎儿组织中CMV-DNA。结果:90例异常孕产史的孕妇羊水检测CMV-DNA,阳性率为38.9%(35/90),其中合并染色数目异常2例(47,XYY和47,XX,+21)(已引产)核型及染色 相似文献
106.
聚合酶链反应诊断单纯疱疹病毒性脑炎 总被引:5,自引:0,他引:5
用聚合酶链反应(PCR)扩增患者脑脊液(ChF)中病毒特异性DNA可早期快速诊断单纯疱疹病毒性脑炎(HSE)。19例临床确诊的病毒性脑炎患者,经PCR在CSF中检出单纯疱疹病毒(HSV)13例,全部阳性标本均经分子杂交证实为HSV-DNA,而14例其他神经疾病(OND)对照组均为阴性,显示了这一方法的特异性。其中7例病毒性脑炎CSF标本分别用PCR分子杂交和病毒分离等三种方法检测HSV;显示PCR最为敏感。表明PCR技术的广泛应用将提高HSE的早期诊断水平,指导临床正确治疗。 相似文献
107.
S. Iwamoto E. Kajii T. Omi T. Kamesaki Y. Akifuji S. Ikemoto 《European journal of haematology》1993,50(5):286-291
Abstract: A patient who represented acute hemolytic crisis was studied. Analysis of the erythrocyte membrane proteins by SDS-PAGE revealed a deficiency of band 4.2. In the family, the sister of the patient who had been clinically normal was also shown to be deficient in band 4.2. Binding studies showed that the propositus' membranes were able to bind normal band 4.2 protein as much as control. It was suggested that the binding sites for the protein were prepared on the membrane. We analyzed the band 4.2 cDNA of the propositus and detected a mutation that changes a codon for alanine to one for threonine at residue 142. Band 4.2 exon III of genomic DNA which included the mutation site was amplified and sequenced directly in the family members, and it was revealed that only the homozygotes of the mutation allele manifested band 4.2 deficiency and the parents, who were heterozygotes, showed normal amounts of band 4.2. Recently, the same mutation was reported as Protein 4.2NIPPON in another 4 cases (Bouhassira et al. Blood 1992: 79: 1846–1854). This study supports the hypothesis that this mutation is the pathogenetic cause of band 4.2 deficiency and not a polymorphism. 相似文献
108.
创面异体移植培养表皮细胞后存活的判定 总被引:1,自引:0,他引:1
应用4种方法判定烧伤创面异体移植的培养表皮细胞存活情况:1.聚合酶链反应(PCR)查Y染色体特异性DNA片段;2.PCR扩增PMCT118长度多态性基因位点;3.PCR/SSOHLA-DQa分型;4.DNA指纹。共检测16例病人的27个活检标本,均证实有供者的DNA,最长时间为移植后92天。初步实验结果表明:培养表皮异体移植后可存活较长时间。 相似文献
109.
杜康宁 《中国脊柱脊髓杂志》1988,(4)
本文讨论用“包络一轨迹”法设计的修正齿形链的传动特性,并提出了完善齿形修正设计的方法,基本上实现消除链传动申的“多边形效应”。 相似文献
110.
目的 探讨可溶性白细胞分化抗原14(soluble cluster of differentiation antigen 14,sCD14)、血管生成素2(angiopoietin 2,Ang2)、C反应蛋白(C-reactive protein,CRP)与急诊创伤骨折伴多发伤患者病情转归的关系及意义。
方法 选取创伤骨折伴多发伤患者324例,根据患者出院时病情转归情况分为良好组(275例)、不良组(49例),比较2组一般资料、sCD14、Ang2、CRP水平,应用Pearson分析sCD14、Ang2、CRP与损伤严重程度评分(injury severity score,ISS)关系,采用Cox回归分析急诊创伤骨折伴多发伤患者病情转归的相关影响因素,采用受试者工作特征曲线(receiver operating characteristic,ROC)分析sCD14、Ang2、CRP对病情转归预测价值。
结果 不良组ISS评分高于良好组(P<0.05);不良组sCD14、Ang2、CRP高于良好组(P<0.05);sCD14(r=0.785)、Ang2(r=0.778)、CRP(r=0.842)与ISS评分呈正相关(P<0.05);sCD14、Ang2、CRP均是预后相关独立危险因素(P<0.05);sCD14、Ang2、CRP预测病情转归的ROC下面积(area under the curve,AUC)依次为0.813、0.757、0.749;挑选出预测敏感度最高(sCD14)、特异度最高(Ang2)的两个指标进行sCD14+Ang2的联合ROC分析显示,两者联合预测病情转归的AUC为0.935,大于任一单一指标(P<0.05)。
结论 sCD14、Ang2、CRP与急诊创伤骨折伴多发伤患者病情严重程度及病情转归有关,均可作为预测病情转归的标志物,但联合检测sCD14、Ang2能提高预测可靠性,为临床诊疗及护理提供更准确的参考信息。 相似文献