全文获取类型
收费全文 | 10973篇 |
免费 | 636篇 |
国内免费 | 29篇 |
专业分类
耳鼻咽喉 | 142篇 |
儿科学 | 674篇 |
妇产科学 | 190篇 |
基础医学 | 1169篇 |
口腔科学 | 271篇 |
临床医学 | 779篇 |
内科学 | 2400篇 |
皮肤病学 | 284篇 |
神经病学 | 709篇 |
特种医学 | 378篇 |
外国民族医学 | 1篇 |
外科学 | 1637篇 |
综合类 | 299篇 |
一般理论 | 11篇 |
预防医学 | 585篇 |
眼科学 | 330篇 |
药学 | 1016篇 |
中国医学 | 51篇 |
肿瘤学 | 712篇 |
出版年
2023年 | 77篇 |
2022年 | 163篇 |
2021年 | 343篇 |
2020年 | 207篇 |
2019年 | 249篇 |
2018年 | 339篇 |
2017年 | 259篇 |
2016年 | 289篇 |
2015年 | 295篇 |
2014年 | 422篇 |
2013年 | 555篇 |
2012年 | 754篇 |
2011年 | 793篇 |
2010年 | 523篇 |
2009年 | 384篇 |
2008年 | 632篇 |
2007年 | 619篇 |
2006年 | 527篇 |
2005年 | 519篇 |
2004年 | 494篇 |
2003年 | 382篇 |
2002年 | 350篇 |
2001年 | 222篇 |
2000年 | 229篇 |
1999年 | 194篇 |
1998年 | 118篇 |
1997年 | 69篇 |
1996年 | 69篇 |
1995年 | 67篇 |
1994年 | 55篇 |
1993年 | 35篇 |
1992年 | 99篇 |
1991年 | 106篇 |
1990年 | 87篇 |
1989年 | 106篇 |
1988年 | 84篇 |
1987年 | 72篇 |
1986年 | 62篇 |
1985年 | 68篇 |
1984年 | 64篇 |
1983年 | 65篇 |
1982年 | 38篇 |
1981年 | 31篇 |
1979年 | 49篇 |
1978年 | 33篇 |
1977年 | 32篇 |
1976年 | 32篇 |
1974年 | 40篇 |
1973年 | 39篇 |
1969年 | 35篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
Context Withania somnifera (L.) Dunal is traditionally used for treating various ailments, but lacks scientific evaluation.Objective This study evaluates Withania somnifera (WS) for its effect on platelet activity and inflammatory enzymes.Materials and methods Aqueous and ethanolic (1:1) leaf extracts were subjected to in vitro indirect haemolytic activity using Naja naja venom, human platelet aggregation was quantified for lipid peroxidation using arachidonic acid (AA) as agonist and 5-lipoxygenase (5-LOX) levels were determined using standard spectrometric assays. Further, molecular docking was performed by the ligand fit method using molegro software package (Molegro ApS, Aarhus, Denmark).Results The study found that aqueous and ethanol extracts have very negligible effect (15%) with an IC50 value of 13.8?mg/mL on PLA2 from Naja naja venom. Further, extracts of WS also had very little effect (18%) with an IC50 value of 16.6?mg/mL on malondialdehyde (MDA) formation. However, a 65% inhibition of 5-LOX with an IC50 value of 0.92?mg/mL was observed in 1:1 ethanol extracts. The same was evident from SAR model with the active ingredient withaferin A binding predominantly on Phe 77, Tyr 98, Arg 99, Asp 164, Leu 168, Ser 382, Arg 395, Tyr 396 and Tyr 614 with an atomic contact energy value of??128.96 compared to standard phenidone (?103.61). Thus, the current study validates the application of WS for inflammatory diseases.Conclusion This study reveals the inhibitory potential of W. somnifera on inflammatory enzymes and platelet aggregation. Thus, WS can serve as a newer, safer and affordable medicine for inflammatory diseases. 相似文献
3.
Evaluation of training nurses to perform semi‐automated three‐dimensional left ventricular ejection fraction using a customised workstation‐based training protocol 下载免费PDF全文
4.
Soosai Manickam Amirtham Ozlem Ozbey Upasana Kachroo Boopalan Ramasamy Elizabeth Vinod 《Clinical anatomy (New York, N.Y.)》2020,33(3):343-349
Bone containing tissues such as osteochondral joint are resistant to routine tissue processing, therefore require decalcification. This technique causes removal of mineral salts, but in the process may macerate the organic tissue, hence the need for tissue fixation. Such severe processing demands careful antigen retrieval to necessitate optimal staining. The aim of our study was to compare five different antigen retrieval protocols (heat retrieval and protein digestion) following decalcification of rabbit knee joints using two different techniques (20% formic acid and 10% ethylenediamine-tetra acetic acid: EDTA). Osteochondral sections were compared based on time required for decalcification, ease of sectioning, morphological integrity using HE staining and antigen preservation (Collagen type II) using immunohistochemistry. The two decalcification solutions did not impair the tissue morphology and ease of sectioning. Joints processed with formic acid decalcified four times faster than EDTA. Among the five antigen retrieval approaches, maximal collagen II uptake with minimal nonspecific staining was found with protein digestion (pronase and hyaluronidase) in both formic acid and EDTA sections. For osteo-chondral sections, we recommend using 10% EDTA for decalcification and pronase plus hyaluronidase for antigen retrieval if maintaining tissue morphology is crucial, whereas if time is of the essence, 20% FA with pronase plus hyaluronidase is the faster option while still preserving structural integrity. Clin. Anat. 33:343–349, 2020. © 2019 Wiley Periodicals, Inc. 相似文献
5.
Mohamed El-Sherbiny Mohamed Ahmed Eladl Anu Vinod Ranade Maha Guimei Hala Gabr 《Singapore medical journal》2020,61(1):39
INTRODUCTIONThis study aimed to investigate the therapeutic response to injected human umbilical cord blood mesenchymal stem cells (UCBMSCs) among albino rats with streptozotocin (STZ)-induced diabetes mellitus.METHODSControl group (GI; n = 25) rats were fed with standard rat diet. Rats with STZ-induced diabetes mellitus without (GII; n = 25) and with (GIII; n = 25) differentiated human UCBMSCs implantation were the test groups. Rats were sacrificed in Week 11 following implantation. Liver biopsies were sectioned and stained in order to highlight both the presence and function of impregnated cells in the liver tissue.RESULTSHaematoxylin and eosin-stained sections in GI and GII rats showed normal liver architecture while GIII rats showed presence of cell clusters inside the liver tissue and around the central veins. Cell clusters with blue cytoplasm were present in sections in GIII rats but absent in GI and GII rats, indicating the presence of injected differentiated human UCBMSCs. The anti-human insulin immunostaining of GIII rats showed clusters of cells within the liver parenchyma and around central veins, indicating that these cells were active and secreting insulin.CONCLUSIONUCBMSCs are proficient in differentiating into insulin-producing cells in vivo under specific conditions and, when transplanted into the liver of albino rats with STZ-induced diabetes mellitus, were able to secrete insulin and partially control the status of diabetes mellitus in rats. 相似文献
6.
7.
8.
Pankaj Dabir Snehal Dabir B V Siva Prasad M V R Reddy 《Infection, genetics and evolution》2006,6(4):287-291
Molecular characterization of Wuchereria bancrofti is essential to develop suitable anti-filarial drugs and vaccines. We describe here isolation, sequence analysis and cloning of a partial cDNA of an enzyme superoxide dismutase from this parasite. The immunoscreening of a lambda zap W. bancrofti microfilarial (Mf) cDNA library with microfilaremic sera had resulted in the isolation of several seroreactive clones including, WbSOD. This clone contained a 309 bp insert and showed significant nucleotide and deduced amino acid sequence homologies to the superoxide dismutases of other nematode parasites. The antioxidant property of this enzyme may have important contribution in the defense mechanism of the parasite against host immune response. 相似文献
9.
J J Rodrigues N J Shaikh D A Gadkari S R Prasad S George P Yergolkar L V Hungund 《The Southeast Asian journal of tropical medicine and public health》1988,19(2):323-326
Brain tissues from 38 patients with a clinical suspicion of encephalitis or encephalopathy were examined by two immunoenzymatic techniques for the detection of arboviral antigen. Group B arboviral antigen was identified in 23 of these tissues. This simple method could be used for the diagnosis of the causal agent of encephalitis. 相似文献
10.