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   640篇
  免费   36篇
  国内免费   3篇
耳鼻咽喉   7篇
儿科学   22篇
妇产科学   16篇
基础医学   85篇
口腔科学   28篇
临床医学   59篇
内科学   139篇
皮肤病学   17篇
神经病学   54篇
特种医学   7篇
外科学   56篇
综合类   7篇
预防医学   25篇
眼科学   70篇
药学   53篇
中国医学   12篇
肿瘤学   22篇
  2023年   12篇
  2022年   18篇
  2021年   55篇
  2020年   14篇
  2019年   26篇
  2018年   36篇
  2017年   20篇
  2016年   22篇
  2015年   23篇
  2014年   34篇
  2013年   44篇
  2012年   62篇
  2011年   52篇
  2010年   27篇
  2009年   18篇
  2008年   30篇
  2007年   44篇
  2006年   16篇
  2005年   28篇
  2004年   13篇
  2003年   10篇
  2002年   9篇
  2001年   3篇
  2000年   7篇
  1999年   2篇
  1998年   2篇
  1995年   1篇
  1994年   1篇
  1993年   2篇
  1992年   6篇
  1991年   3篇
  1990年   4篇
  1989年   1篇
  1988年   4篇
  1987年   9篇
  1986年   2篇
  1985年   2篇
  1984年   1篇
  1983年   1篇
  1981年   2篇
  1979年   2篇
  1978年   1篇
  1974年   1篇
  1973年   1篇
  1945年   1篇
  1944年   2篇
  1943年   1篇
  1942年   1篇
  1900年   1篇
  1899年   1篇
排序方式: 共有679条查询结果,搜索用时 15 毫秒
101.
Receptivity to strategies to improve the food environment by increasing access to healthier foods in small food stores is underexplored. We conducted 20 in-depth interviews with small storeowners of different ethnic backgrounds as part of a small-store intervention trial. Store owners perceived barriers and facilitators to purchase, stock, and promote healthy foods. Barriers mentioned included customer preferences for higher fat and sweeter taste and for lower prices; lower wholesaler availability of healthy food; and customers’ lack of interest in health. Most store owners thought positively of taste tests, free samples, and communication interventions. However, they varied in terms of their expectations of the effect of these strategies on customers’ healthy food purchases. The findings reported add to the limited data on motivating and working with small-store owners in low-income urban settings.  相似文献   
102.
In this work, two different in vitro gastric digestion models were used to evaluate the stability of a live attenuated rotavirus vaccine candidate (RV3-BB) under conditions designed to mimic oral delivery in infants. First, a forced-degradation model was established at low pH to assess the buffering capacity of formulation excipients and to screen for RV3-BB stabilizers. Second, a sequential-addition model was implemented to examine RV3-BB stability under conditions more representative of oral administration to infants. RV3-BB rapidly inactivated at < pH 5.0 (37 °C, 1 h) as measured by an infectivity RT-qPCR assay. Pre-neutralization with varying volumes of infant formula (Enfamil®) or antacid (Mylanta®) conferred partial to full protection of RV3-BB. Excipients with sufficient buffering capacity to minimize acidic pH inactivation of RV3-BB were identified (e.g., succinate, acetate, adipate), however, they concomitantly destabilized RV3-BB in accelerated storage stability studies. Both effects were concentration dependent, thus excipient optimization was required to design candidate RV3-BB formulations which minimize acid-induced viral inactivation during oral delivery while not destabilizing the vaccine during long-term 2–8 °C storage. Finally, a statistical Design -of-Experiments (DOE) study examining RV3-BB stability in the in vitro sequential-addition model identified key formulation parameters likely affecting RV3-BB stability during in vivo oral delivery.  相似文献   
103.

Objective

To measure the frequency of antimicrobial resistance in pediatric blood culture isolates of Escherichia coli and Klebsiella spp. with focus on carbapenem resistance.

Methods

Over a period of three years, pediatric blood culture isolates were tested for antimicrobial susceptibility, including molecular investigations for carbapenem resistance.

Results

Amikacin, carbapenems, colistin and tigecycline had an antimicrobial efficacy of >70% (n=140). 7 of the 15 randomly selected isolates were positive for carbapenemase gene; among them, five were New Delhi Metallo β-lactamase (NDM).

Conclusion

There was a high prevalence of Klebsiella spp. in pediatric bacteremia and dissemination of NDMmediated carbapenem resistance in pediatric wards.
  相似文献   
104.
105.
106.
This study investigated the steady-state pharmacokinetic interaction between the HIV protease inhibitor, darunavir (TMC114), administered with low-dose ritonavir (darunavir/ritonavir), and clarithromycin in HIV-negative healthy volunteers. In a 3-way crossover study, 18 individuals received darunavir/ritonavir 400/100 mg bid, clarithromycin 500 mg bid, and darunavir/ritonavir 400/100 mg bid plus clarithromycin 500 mg bid in 3 separate sessions for 7 days, with a washout period of at least 7 days between treatments. Pharmacokinetic assessment was performed on day 7. Safety and tolerability of the study medication were monitored throughout. Coadministration of darunavir/ritonavir with clarithromycin resulted in a reduction in darunavir maximum plasma concentration (Cmax) and area under the curve from administration until 12 hours postdose (AUC12 h) of 17% and 13%, respectively. Ritonavir Cmax and AUC12 h were unchanged. During coadministration with darunavir/ritonavir, clarithromycin Cmax and AUC12 h increased by 26% and 57%, respectively; 14-hydroxy-clarithromycin plasma concentrations were reduced to below the lower limit of quantification (<50 ng/mL). The study medication was generally well tolerated. Based on these pharmacokinetic findings, neither clarithromycin nor darunavir/ritonavir dose adjustments are necessary when clarithromycin is coadministered with darunavir/ritonavir.  相似文献   
107.
This study aims to describe the clinicopathological features and outcomes of patients who underwent orbital exenteration at a tertiary eye care center in south India. Retrospective chart reviews were performed on all patients undergoing orbital exenteration from January 1999 to December 2012. Parameters recorded include demographic data, clinical presentations, past medical or surgical interventions, exenteration notes, histopathological diagnosis, adjunctive treatment, follow-up examination findings, recurrences, complications, and their management. Orbital exenteration was performed on 119 orbits of 119 patients over a 14-year period. The mean age was 48.9 years (range 1–82 years). The indications were malignancies in 90.7 % (108/119), while 9.3 % (11/119) of cases were exenterated for non-malignant indications. Among the malignancies, the commonest tissue of origin was conjunctiva, noted in 45.4 % (49/108), followed by eyelids (25.9 %, 28/108), orbit (19.4 %, 21/108), and intraocular tissues (9.3 %, 10/108). The commonest malignancies noted in this series were an extensive ocular surface squamous neoplasia (OSSN) (44.4 %, 48/108) and sebaceous gland carcinoma of eyelids with an orbital involvement (18.5 %, 20/108). Extensive fungal granuloma (mucormycosis-4, aspergillosis-4) was the commonest (81.8 %, 9/11) indication among the non-malignant group. All complications were wound related, and none had a recurrence at a mean follow-up of 12.8 months. Extensive orbital involvement with OSSN and SGC were the commonest indications for exenteration. There is a need of creating awareness among general ophthalmologists in specific geographical regions regarding early diagnosis, standardized protocols of management, and appropriate referral.  相似文献   
108.
109.
110.
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