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31.
The effect of both intrahypothalamic and systemic administration of guanosine triphosphate (GTP) on lordosis behavior was studied in ovariectomized and ovariectomized-adrenalectomized, estrogen-primed rats (estradiol benzoate, 4 μg). This estrogen dose per se induced only weak or no lordosis behavior. Injection of GTP into the medial hypothalamic area (100 μg in 2.5 μl) elicited lordosis behavior with relatively short latency in 6 out of 7 rats. Systemic administration of GTP in a dose range of 0.8 mg to 5.0 mg to ovariectomized estrogen-primed rats, stimulated intense lordosis behavior in all subjects. Weak lordosis responses were displayed within the first 12 hr after GTP injection, but at 48 hr all rats were highly estrous. Lordosis behavior remained for up to eight days, its duration being related to the dose of GTP administered. GTP (2 mg) induced lordosis behavior in ovariectomized, adrenalectomized estrogen-primed rats, thus excluding the participation of adrenal steroids in this effect. The results are interpreted in terms of the stimulation of adenyl cyclase-cAMP systems by GTP. 相似文献
32.
Joseph G. Altin Eloisa B. Pagler Christopher R. Parish 《European journal of immunology》1994,24(2):450-457
Previous studies have reported an association of the cell surface adhesion molecule CD2 with the T cell receptor and with CD45 on mouse and human T lymphocytes. In this study the association of CD2 with cell surface molecules was investigated using cell surface biotinylation of T lymphocytes, coupled with immunoprecipitation using two CD2-specific monoclonal antibodies (mAb) (RM2–5 and 12–15) and analysis by SDS-PAGE. Although both CD2 mAb immunoprecipitated CD2 from lysates of murine lymphocytes, it was found that mAb 12–15, but not RM2–5, co-precipitated two other molecules of 95 and 180 kDa. Subsequent studies revealed that the 95- and 180-kDa molecules were associated with a subspecies of CD2 (? 5%) on thymocytes, the antigen-specific T cell line D10, and splenic T cells but not B cells. Two lines of evidence were obtained consistent with the 95- and 180-kDa molecules being the β and α chains of LFA-1. Firstly, an analysis of 12–15 mAb immunoprecipitates on 4–12% gels under reducing and nonreducing conditions shows that the 95- and 180-kDa molecules have a molecular weight and migration pattern identical to LFA-1. Secondly, depletion of LFA-1 from lysates with LFA-1 mAb abolished the ability of CD2 mAb 12–15 to co-precipitate the 95- and 180-kDa molecules, thereby identifying these as the β and α chains of mouse LFA-1, respectively. These results provide evidence for the first time for an association of LFA-1 and CD2 on mouse T lymphocytes, and suggest that the association occurs with an immunologically distinct subspecies of CD2 molecules. 相似文献
33.
S. W. Schneider J. Lärmer R. M. Henderson H. Oberleithner 《Pflügers Archiv : European journal of physiology》1998,435(3):362-367
Proteins are usually identified by their molecular weights, and atomic force microscopy (AFM) produces images of single molecules
in three dimensions. We have used AFM to measure the molecular volumes of a number of proteins and to determine any correlation
with their known molecular weights. We used native proteins (the TATA-binding protein Tbp, a fusion protein of glutathione-S-transferase and the renal potassium channel protein ROMK1, the immunoglobulins IgG and IgM, and the vasodilator-stimulated
phosphoprotein VASP) and also denatured proteins (the red blood cell proteins actin, Band 3 and spectrin separated by SDS-gel
electrophoresis and isolated from nitrocellulose). Proteins studied had molecular weights between 38 and 900 kDa and were
imaged attached to a mica substrate. We found that molecular weight increased with an increasing molecular volume (correlation
coefficient = 0.994). Thus, the molecular volumes measured with AFM compare well with the calculated volumes of the individual
proteins. The degree of resolution achieved (lateral 5 nm, vertical 0.2 nm) depended upon the firm attachment of the proteins
to the mica. This was aided by coating the mica with suitable detergent and by imaging using the AFM tapping mode which minimizes
any lateral force applied to the protein. We conclude that single (native and denatured) proteins can be imaged by AFM in
three dimensions and identified by their specific molecular volumes. This new approach permits detection of the number of
monomers of a homomultimeric protein and study of single proteins under physiological conditions at the molecular level.
Received: 14 February 1997 / Received after revision: 8 September 1997 / Accepted: 8 September 1997 相似文献
34.
Usual human livers contain two major ALDH isozymes, i.e., cytosolic ALDH1 and mitochondrial ALDH2, while approximately 50% of Orientals are "atypical" and have only the ALDH1 and are missing the ALDH2. Instead, the atypical livers contain an enzymatically inactive but immunologically cross-reactive material (CRM) corresponding to the ALDH2 component. Some Orientals are found to be atypical also in the ALDH1 locus, i.e., they are missing the enzymatically active ALDH1 but contain a large amount of CRM corresponding to the ALDH1 component. cDNA for ALDH1 and that for ALDH2 were cloned and their nucleotide sequences were determined. The amino acid sequences of ALDH1 and ALDH2 were deduced from their cDNA sequences. The molecular abnormality of the inactive ALDH2(2) is found to be the substitution of Glu at the 14th position from the COOH-terminal of the protein by Lys which resulted from G----A transition in the gene. 相似文献
35.
宫颈癌是最常见的妇科恶性肿瘤之一。目前人乳头瘤病毒(HPV)检测及细胞学检查是宫颈癌及其癌前病变(CCPL)的主要筛查手段。由于上述传统筛查方法,仍然存在对CCPL漏诊的风险,因此寻找有效识别CCPL的特异性分子标志物,具有重要临床意义。对具有序列相似性家族19成员A4(FAM19A4)基因启动子甲基化定量检测,可有效检出CCPL组织,较传统筛查方法有较高特异度,有望成为CCPL筛查的特异性分子标志物。笔者拟就FAM19A4基因启动子甲基化定量检测,在CCPL筛查中应用的最新研究现状进行阐述,旨在为进一步推进CCPL筛查方法的开发,提供思路。 相似文献
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39.
Francesca Giunchi Tania Franceschini Michelangelo Fiorentino 《Translational andrology and urology》2021,10(3):1553
Few molecular prognostic and predictive biomarkers have been identified so far in genitourinary tumors. We started from a literature search to explore the status of the art of molecular pathology tests as diagnostic, prognostic, predictive biomarkers in genitourinary cancers. Next generation sequencing approaches now provide mind-changing information in the fields of kidney cancer diagnosis, predictive oncology of urothelial cancer, understanding the causes of testicular and penile cancer, and the comprehension of the drivers of prostate cancer progression beyond androgen regulation. The classification of kidney cancer will be based soon on molecular changes. The causes of non-HPV related penile cancer are largely unknown. The emerging high incidence of testicular cancer could be explained only on the basis of molecular changes. The response to novel therapeutic agents in prostatic and urothelial cancer will require thorough molecular tumor characterization. The hereditary risk of patients with early onset prostate cancer and their potential treatment with targeted therapy requires germline and somatic genetic assays. The implementation of effective biomarkers for the response to immune check-point inhibitors in genitourinary cancer is based on the assessment of inflammatory expression profiles and the tumor mutational burden. This review deals with the current tests and provides a tentative foresee of the future molecular biomarkers of genitourinary cancer. 相似文献
40.
目的探讨肺炎克雷伯菌对碳青霉烯类抗菌药物耐药的主要产酶机制及同源性。方法收集长沙市第一医院2016年12月-2017年12月临床分离的非重复碳青霉烯耐药肺炎克雷伯菌(CRKP),采用改良碳青霉烯酶灭活试验(mCIM)检测碳青霉烯酶,聚合酶链反应(PCR)法检测常见耐药编码基因。脉冲场凝胶电泳(PFGE)和多位点序列分型(MLST)分析同源性。结果共收集到57株CRKP,mCIM试验阳性率为91.23%(52/57)。PCR共检出6种耐药基因,包括blaSHV、blaCTX-M-9群、blaKPC-2、blaTEM、blaCTX-M-1群和blaNDM-1,检出率分别为94.74%、68.42%、68.42%、56.14%、3.51%和1.75%,其中2株携带blaCTX-M-1群的菌株经测序证实为blaCTX-M-80和blaCTX-M-123,blaCTX-M-9群中1株为blaCTX-M-27,2株为blaCTX-M-14,其余均为blaCTX-M-65。PFGE结果显示,57株CRKP可分为A~H共8种不同的型别,以A型为主,占76.79%,其中A6亚型占32.56%。MLST结果显示,共检出ST11和ST29两种型别,以ST11为主,占75.00%。结论该院临床分离的肺炎克雷伯菌对碳青霉烯类抗菌药物耐药的重要机制为产KPC-2型碳青霉烯酶,且同时携带多种超广谱β-内酰胺酶(ESBLs)耐药基因。PFGE和MLST结果表明:该院临床分离的CRKP存在克隆传播,需加强流行病学监控。 相似文献