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   1200篇
  免费   117篇
  国内免费   46篇
耳鼻咽喉   2篇
儿科学   63篇
妇产科学   41篇
基础医学   189篇
口腔科学   36篇
临床医学   221篇
内科学   204篇
皮肤病学   42篇
神经病学   43篇
特种医学   158篇
外科学   89篇
综合类   75篇
一般理论   1篇
预防医学   69篇
眼科学   6篇
药学   92篇
中国医学   1篇
肿瘤学   31篇
  2022年   7篇
  2021年   18篇
  2020年   11篇
  2019年   12篇
  2018年   30篇
  2017年   7篇
  2015年   16篇
  2014年   26篇
  2013年   48篇
  2012年   20篇
  2011年   35篇
  2010年   41篇
  2009年   33篇
  2008年   29篇
  2007年   53篇
  2006年   28篇
  2005年   29篇
  2004年   27篇
  2003年   28篇
  2002年   25篇
  2001年   42篇
  2000年   40篇
  1999年   54篇
  1998年   54篇
  1997年   40篇
  1996年   40篇
  1995年   31篇
  1994年   23篇
  1993年   27篇
  1992年   38篇
  1991年   28篇
  1990年   26篇
  1989年   52篇
  1988年   57篇
  1987年   37篇
  1986年   31篇
  1985年   48篇
  1984年   22篇
  1983年   15篇
  1982年   13篇
  1981年   8篇
  1980年   12篇
  1979年   5篇
  1978年   15篇
  1977年   19篇
  1976年   7篇
  1975年   7篇
  1974年   8篇
  1973年   9篇
  1972年   15篇
排序方式: 共有1363条查询结果,搜索用时 31 毫秒
41.
Background: There are no FDA-approved pharmacotherapies for cannabis use disorders (CUD), despite the evaluation of numerous medications. Notably, chronic dosing of oral naltrexone decreases self-administration of cannabis in human laboratory studies.

Objectives: To test the feasibility of long-acting injectable naltrexone for the treatment of CUD, while obtaining preliminary safety and efficacy data.

Methods: Twelve adult participants (seven male) meeting DSM-IV-TR criteria for cannabis dependence enrolled into an 8-week, open-label pilot study conducted at an academic treatment research clinic. They received 380 mg intramuscular injections of long-acting naltrexone on study day 1 and at the start of study week 5. Outcome measures included percentages of study completers and participants who received the second injection, frequency of adverse events (AEs), and cannabis consumption measured by average daily grams, dollars, and using days per week as measured by timeline follow-back and urine oral delta-9-tetrahydrocannabinol (THC) concentrations.

Results: Of the 12 participants enrolled in the study, 9 completed the study and 6 received the second injection. There were no severe AEs but an unexpected AE led to the addition of supportive medications to the protocol. Number of cannabis use days per week significantly decreased over the course of the study (p = .001). Creatinine-corrected urine THC concentrations and average daily cannabis use per study week in grams and in dollars did not decrease over the course of the study.

Conclusions: Long-acting injectable naltrexone is a feasible intervention for CUD worthy of further study in a placebo-controlled, double-blinded randomized clinical trial.  相似文献   

42.
43.
44.
Microbiota composition and associated metabolic activities are essential for the education and development of a healthy immune system. Microbial dysbiosis, caused by risk factors such as diet, birth mode, or early infant antimicrobial therapy, is associated with the inception of allergic diseases. In turn, allergic diseases increase the risk for irrational use of antimicrobial therapy. Microbial therapies, such as probiotics, have been studied in the prevention and treatment of allergic diseases, but evidence remains limited due to studies with high heterogeneity, strain-dependent effectiveness, and variable outcome measures. In this review, we sketch the relation of microbiota with allergic diseases, the overuse and rationale for the use of antimicrobial agents in allergic diseases, and current knowledge concerning the use of bacterial products in allergic diseases. We urgently recommend 1) limiting antibiotic therapy in pregnancy and early childhood as a method contributing to the reduction of the allergy epidemic in children and 2) restricting antibiotic therapy in exacerbations and chronic treatment of allergic diseases, mainly concerning asthma and atopic dermatitis. Future research should be aimed at antibiotic stewardship implementation strategies and biomarker-guided therapy, discerning those patients that might benefit from antibiotic therapy.  相似文献   
45.
46.
47.
Introduction: PPIs are involved in every disease and specific modulation of these PPIs with small molecules would significantly improve our prospects of developing therapeutic agents. Both industry and academia have engaged in the identification and use of PPI inhibitors. However in comparison, the opposite strategy of employing small-molecule stabilizers of PPIs is underrepresented in drug discovery.

Areas covered: PPI stabilization has not been exploited in a systematic manner. Rather, this concept validated by a number of therapeutically used natural products like rapamycin and paclitaxel has been shown retrospectively to be the basis of the activity of synthetic molecules originating from drug discovery projects among them lenalidomide and tafamidis. Here, the authors cover the growing number of synthetic small-molecule PPI stabilizers to advocate for a stronger consideration of this as a drug discovery approach.

Expert opinion: Both the natural products and the growing number of synthetic molecules show that PPI stabilization is a viable strategy for drug discovery. There is certainly a significant challenge to adapt compound libraries, screening techniques and downstream methodologies to identify, characterize and optimize PPI stabilizers, but the examples of molecules reviewed here in our opinion justify these efforts.  相似文献   
48.
49.
JB Ma  SX Yao  H  Li  Q  Pei JF  Yao 《美中国际创伤杂志》2014,(1):1-4,9
In this case, a male patient presented with a clinically and radiographieally unstable slipped capital femoral epiphysis (SCFE) as well as slipped calcaneal epiphysis years. Subsequent thorough at the age of 23 work-up revealed that he had some features of rickets and labo- ratory test demonstrated he had hypophos- phatemia (2.3mg/dl), normocalcemia, normal vi- tamin D metabolite levels, and secondary hy- perparathyroidism.  相似文献   
50.
The recent occurrence of deaths associated with the psychostimulant cis‐4,4′‐dimethylaminorex (4,4′‐DMAR) in Europe indicated the presence of a newly emerged psychoactive substance on the market. Subsequently, the existence of 3,4‐methylenedioxy‐4‐methylaminorex (MDMAR) has come to the authors' attention and this study describes the synthesis of cis‐ and trans‐MDMAR followed by extensive characterization by chromatographic, spectroscopic, mass spectrometric platforms and crystal structure analysis. MDMAR obtained from an online vendor was subsequently identified as predominantly the cis‐isomer (90%). Exposure of the cis‐isomer to the mobile phase conditions (acetonitrile/water 1:1 with 0.1% formic acid) employed for high performance liquid chromatography analysis showed an artificially induced conversion to the trans‐isomer, which was not observed when characterized by gas chromatography. Monoamine release activities of both MDMAR isomers were compared with the non‐selective monoamine releasing agent (+)‐3,4‐methylenedioxymethamphetamine (MDMA) as a standard reference compound. For additional comparison, both cis‐ and trans‐4,4′‐DMAR, were assessed under identical conditions. cis‐MDMAR, trans‐MDMAR, cis‐4,4′‐DMAR and trans‐4,4′‐DMAR were more potent than MDMA in their ability to function as efficacious substrate‐type releasers at the dopamine (DAT) and norepinephrine (NET) transporters in rat brain tissue. While cis‐4,4′‐DMAR, cis‐MDMAR and trans‐MDMAR were fully efficacious releasing agents at the serotonin transporter (SERT), trans‐4,4′‐DMAR acted as a fully efficacious uptake blocker. Currently, little information is available about the presence of MDMAR on the market but the high potency of ring‐substituted methylaminorex analogues at all three monoamine transporters investigated here might be relevant when assessing the potential for serious side‐effects after high dose exposure. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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