首页 | 官方网站   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   5354篇
  免费   282篇
  国内免费   32篇
医药卫生   5668篇
  2023年   74篇
  2022年   58篇
  2021年   296篇
  2020年   191篇
  2019年   204篇
  2018年   228篇
  2017年   156篇
  2016年   185篇
  2015年   249篇
  2014年   285篇
  2013年   288篇
  2012年   427篇
  2011年   403篇
  2010年   232篇
  2009年   197篇
  2008年   307篇
  2007年   291篇
  2006年   298篇
  2005年   276篇
  2004年   229篇
  2003年   214篇
  2002年   171篇
  2001年   48篇
  2000年   54篇
  1999年   33篇
  1998年   25篇
  1997年   18篇
  1996年   16篇
  1995年   13篇
  1994年   15篇
  1993年   7篇
  1992年   22篇
  1991年   18篇
  1990年   19篇
  1989年   13篇
  1988年   14篇
  1987年   13篇
  1986年   5篇
  1985年   10篇
  1984年   5篇
  1983年   6篇
  1980年   5篇
  1979年   5篇
  1977年   5篇
  1974年   6篇
  1973年   4篇
  1972年   4篇
  1970年   5篇
  1969年   4篇
  1968年   3篇
排序方式: 共有5668条查询结果,搜索用时 46 毫秒
1.
PurposeThe clinical manifestations of rickettsial diseases mimic other endemic infections with similar presentations thus posing a serious challenge to clinicians for their diagnosis. For the diagnosis of rickettsial disease serological tests like Weil Felix, ELISA and IFA are used. There are limited studies that have evaluated different serological tests for the diagnosis of rickettsial diseases. Therefore, the present study was undertaken to evaluate the ELISA and Weil Felix test for the diagnosis of rickettsial diseases prevalent in this region.MethodsSamples from 281 patients clinically suspected of rickettsial diseases were tested for spotted fever group (SFG), typhus group (TG) and scrub typhus group (STG) by Weil Felix, ELISA and IFA was taken as the gold standard. Baseline titers and cut-off ODs were calculated by taking samples from healthy blood donors.ResultsThe sensitivity, specificity, positive and negative predictive value of Weil Felix test ranged from 30% to 44%, 83.46%–97.86%, 9%–77%, 92–96% respectively. The sensitivity and specificity, positive and negative predictive value of ELISA ranged from 80.77% to 96.15%, 96.33%–98.43%, 70.21%–88.64%, 92.89%–99.60% respectively. Maximum cross-reactions were observed between SFG and STG by the Weil Felix test and between STG and TG by ELISA.ConclusionsELISA was found to be sensitive and specific for the diagnosis of rickettsial diseases. It is easy to perform, does not require a technical expert for result interpretation and a large number of samples can be processed at a time.  相似文献   
2.
3.
4.
5.
6.
7.
Lasers in Medical Science - Vitiligo is a chronic acquired disease. Various therapeutic strategies are available but with variable degrees of success. Fractional CO2 laser is claimed to be...  相似文献   
8.

Introduction

Bariatric surgery is an increasingly common treatment of morbid obesity in the United States and has demonstrated effective weight loss and improvement of comorbidities. We used the National Surgical Quality Improvement Program (NSQIP) data to characterize bariatric surgery utilization and complication rates in the adolescent population.

Methods

Demographics, surgical procedures, comorbidities, and 30-day outcomes of 2625 adolescents ages 18–21 who underwent bariatric surgery were analyzed from NSQIP data-bank from 2005 to 2015.

Results

79.5% of patients were females. Majority of patients identified as Caucasian or Black/African American (BAA) at 66.7% (73% of US population) and 15.5% (12.6% of US population), respectively. 15.9% identified as Hispanic. Comorbidities included diabetes in 9.3% (7.8% NIDDM), hypertension (9.5%), and dyspnea on moderate exertion (13.2%).Sleeve Gastrectomy, Laparoscopic Roux-En-Y (RY) and Adjustable Gastric Banding (AGB) were the three most common procedures performed during the study period. There has been a sharp trend towards SG in recent years (11.4% in 2010, to 66.6% in 2015), while RY utilization declined (47.4% in 2010 to 28.6% in 2015). Surgical complications were 2.4%, with the most common being superficial surgical site infection (0.7%), UTI (0.7%), and organ-space infection (0.4%). Reoperation and readmission rates within 30-days post-operation were 1.5% and 4.1%, respectively. Those with complications had longer length-of-stays (2.7 vs. 1.8?days, P?<?0.001), greater reoperation rates (OR?=?9.6, P?<?0.001) and readmission rates (OR?=?11.8, P?<?0.001).

Conclusion

Morbid obesity is associated with significant comorbidity. SG is increasingly the most utilized form of bariatric surgery. While complications are low, they are associated with greater hospital length-of-stay, readmission, and reoperation rates.

Level of Evidence

Treatment Study, Level III.  相似文献   
9.
Background: Betel quid chewing is more common among the older generation in rural areas of Malaysia. Oral cancer in Asia has been associated with the habit of chewing betel quid and areca nut. Objective:  This study aims to investigate the cytotoxic effects of betel quid and areca nut extracts on the fibroblast (L929), mouth-ordinary-epithelium 1 (MOE1) and oral squamous cell carcinoma (HSC-2) cell lines. Methods: L929, MOE1 and HSC-2 cells were treated with 0.1, 0.2 and 0.4 g/ml of betel quid and areca nut extracts for 24, 48 and 72 h. MTT assay was performed to assess the cell viability. Results: Both extracts, regardless of concentration, significantly reduced the cell viability of L929 compared with the control (P<0.05). Cell viability of MOE1 was significantly enhanced by all betel quid concentrations compared with the control (P<0.05). By contrast, 0.4 g/ml of areca nut extract significantly reduced the cell viability of MOE1 at 48 and 72 h of incubation. Cell viability of HSC-2 was significantly lowered by all areca nut extracts, but 0.4 g/ml of betel quid significantly increased the cell viability of HSC-2 (P<0.05). Conclusion: Areca nut extract is cytotoxic to L929 and HSC-2, whereas the lower concentrations of areca nut extract significantly increased the cell viability of MOE1 compared to the higher concentration and control group. Although betel quid extract is cytotoxic to L929, the same effect is not observed in MOE1 and HSC-2 cell lines. Further investigations are needed to clarify the mechanism of action.  相似文献   
10.

Background

Herbal medicine has been widely utilized by pregnant women despite the limited available evidence regarding the safety and efficacy of that practice. The current available studies, from different countries, estimated that the use of herbal medicine during pregnancy range from 7% up to 96%. The aim of this study is to determine the prevalence, attitude, source of information, and reasoning behind the use of herbal medicine among pregnant women in Saudia Arabia.

Methods

A cross-sectional study conducted using a convenience sample including pregnant women who visited the obstetric clinics at King Abdulaziz Medical City in Riyadh, Saudi Arabia. A survey was administered in order to evaluate the prevalence and perception toward herbal medicine use among pregnant women in Saudi Arabia.

Results

A total of 297 pregnant women completed the survey. The results showed that 56% of the respondents have used some type of herbal medicine during their pregnancy. Olive oil was utilized in 26% of the respondents followed by cumin 20% and garlic 15%. In addition, 37% of the respondents used herbal medicine by their own initiative, while 33% and 12% used herbal medicine based on recommendations from their families and friends, respectively. Furthermore, 19% of the respondents reported a positive attitude toward herbal medicine use during pregnancy. In addition, the percentage of women with positive attitude was marginally higher among respondents with lower educational level.

Conclusion

The prevalence of using herbal medicine is considerably high among pregnant women in Saudi Arabia. Unfortunately, the majority of the users relied on informal sources to use herbal medicine during pregnancy.  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-23

京公网安备 11010802026262号