首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   3983篇
  免费   294篇
  国内免费   39篇
耳鼻咽喉   63篇
儿科学   119篇
妇产科学   140篇
基础医学   471篇
口腔科学   101篇
临床医学   510篇
内科学   731篇
皮肤病学   82篇
神经病学   213篇
特种医学   257篇
外国民族医学   1篇
外科学   660篇
综合类   166篇
一般理论   1篇
预防医学   224篇
眼科学   90篇
药学   226篇
中国医学   5篇
肿瘤学   256篇
  2021年   36篇
  2020年   31篇
  2019年   52篇
  2018年   71篇
  2017年   45篇
  2016年   56篇
  2015年   62篇
  2014年   111篇
  2013年   133篇
  2012年   185篇
  2011年   172篇
  2010年   125篇
  2009年   129篇
  2008年   193篇
  2007年   171篇
  2006年   199篇
  2005年   157篇
  2004年   130篇
  2003年   160篇
  2002年   174篇
  2001年   117篇
  2000年   146篇
  1999年   107篇
  1998年   63篇
  1997年   50篇
  1996年   42篇
  1995年   51篇
  1994年   35篇
  1993年   31篇
  1992年   73篇
  1991年   79篇
  1990年   79篇
  1989年   92篇
  1988年   83篇
  1987年   86篇
  1986年   78篇
  1985年   70篇
  1984年   57篇
  1983年   68篇
  1982年   42篇
  1981年   47篇
  1980年   42篇
  1979年   51篇
  1978年   27篇
  1977年   25篇
  1975年   22篇
  1974年   39篇
  1973年   25篇
  1972年   30篇
  1969年   27篇
排序方式: 共有4316条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
5.
6.
PurposeTo evaluate the effect of controlled ovarian hyperstimulation length and total gonadotropin (GN) dose on recipient live birth rate (LBR) in fresh donor oocyte cycles.MethodsData was obtained from SART CORS on all fresh donor oocyte GnRH antagonist cycles (n = 1049) between 2014 and 2015 which resulted in a single embryo transferred. Donor and recipient demographic information and cycle characteristics were extracted. Binomial regression was used to estimate LBR with respect to days of stimulation (DOS) and total GN dose. Multivariate analysis was performed to evaluate these relationships after controlling for confounders.ResultsOverall LBR in fresh donor oocyte cycles was 57%. Average stimulation length was 14.3 ± 4.9 days, and total GN dose was 2464 ± 1062 IU. On univariate analysis, neither days of stimulation (p = 0.5) nor total GN dose (p = 0.57) was independently correlated with LBR. However, in prolonged stimulations (> 15 days) with high total GN dose (> 3000 IU), as both the cycle length and total GN dose increased, LBR significantly decreased from 63.81 to 48.15% (p = 0.02) and from 67.61 to 48.15% (p = 0.01), respectively. Multivariate analysis showed no significant effect of either DOS or total GN dose on LBR.ConclusionsLBR is significantly decreased in fresh donor oocyte cycles when cycles are prolonged with high total GN dose. However, after controlling for confounders neither DOS nor total GN dose significantly affects LBR.  相似文献   
7.
8.

Purpose

The aim of this study was to formulate nano-emulsions comprising natural oils and the active pharmaceutical ingredients (APIs) clofazimine (CLF), artemisone (ATM) and decoquinate (DQ) in order to determine effectiveness of the nano-emulsions for topical delivery of the APIs. The APIs alone do not possess suitable physicochemical properties for topical drug delivery.

Methods

Nano-emulsions were formulated with olive and safflower oils encapsulating the APIs. Skin diffusion and tape stripping studies were performed. By using the lactate dehydrogenase (LDH) assay, in vitro toxicity studies were carried out on immortalized human keratinocytes (HaCaT) cell line to determine cytotoxicities due to the APIs and the nano-emulsions incorporating the APIs.

Results

The nano-emulsions were effective in delivering the APIs within the stratum corneum-epidermis and the epidermis-dermis, were non-cytotoxic towards HaCaT cell lines (p <?0.05) and inhibited Mycobacterium tuberculosis in vitro.

Conclusion

Natural oil nano-emulsions successfully deliver CLF, ATM and DQ and in principle could be used as supplementary topical treatment of cutaneous tuberculosis (CTB).
Graphical Abstract ?
  相似文献   
9.
Pharmacogenetics influences oral tacrolimus exposure; however, little data exist regarding i.v. tacrolimus. We investigated the impact of genetic polymorphisms in CYP3A4, CYP3A5, and ABCB1 on i.v. tacrolimus exposure and toxicity in adult patients receiving an allogeneic hematopoietic stem cell transplant for hematologic malignancies. Germline DNA was extracted from buccal swabs and genotyped for CYP3A4, CYP3A5, and ABCB1 polymorphisms. Continuous i.v. infusion of tacrolimus .03 mg/kg/day was initiated on day +5 post-transplant, and steady-state blood concentrations were measured 4days later. We evaluated the association between phenotypes and prevalence of nontherapeutic target concentrations (below or above 5 to 15 ng/mL) as well as tacrolimus-related toxicities. Of 63 patients, 28.6% achieved the target concentration; 71.4% were >15ng/mL, which was more common in CYP3A4 intermediate/normal metabolizers (compared with rapid) and those with at least 1 ABCB1 C2677T loss-of-function allele (P < .05). ABCB1 C2677T was significantly associated with concentrations >15ng/mL (odds ratio, 6.2; 95% confidence interval, 1.8 to 23.6; P = .004) and tacrolimus-related toxicities (odds ratio, 7.5; 95% confidence interval, 1.6 to 55.2; P = .02). ABCB1 C2677T and CYP3A4 are important determinants of i.v. tacrolimus exposure, whereas ABCB1 C2677T also impacts tacrolimus-related toxicities in stem cell transplants.  相似文献   
10.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号