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   3456篇
  免费   342篇
  国内免费   53篇
耳鼻咽喉   10篇
儿科学   235篇
妇产科学   55篇
基础医学   448篇
口腔科学   136篇
临床医学   407篇
内科学   883篇
皮肤病学   42篇
神经病学   223篇
特种医学   191篇
外科学   333篇
综合类   34篇
一般理论   1篇
预防医学   230篇
眼科学   20篇
药学   342篇
  1篇
中国医学   11篇
肿瘤学   249篇
  2023年   17篇
  2021年   27篇
  2020年   35篇
  2019年   47篇
  2018年   69篇
  2017年   71篇
  2016年   67篇
  2015年   74篇
  2014年   108篇
  2013年   142篇
  2012年   126篇
  2011年   146篇
  2010年   111篇
  2009年   142篇
  2008年   150篇
  2007年   157篇
  2006年   123篇
  2005年   162篇
  2004年   128篇
  2003年   116篇
  2002年   97篇
  2001年   127篇
  2000年   111篇
  1999年   90篇
  1998年   110篇
  1997年   110篇
  1996年   83篇
  1995年   83篇
  1994年   69篇
  1993年   66篇
  1992年   70篇
  1991年   64篇
  1990年   73篇
  1989年   74篇
  1988年   66篇
  1987年   62篇
  1986年   59篇
  1985年   58篇
  1984年   39篇
  1983年   40篇
  1982年   30篇
  1981年   40篇
  1980年   24篇
  1979年   21篇
  1978年   22篇
  1977年   22篇
  1976年   15篇
  1975年   14篇
  1973年   14篇
  1970年   12篇
排序方式: 共有3851条查询结果,搜索用时 9 毫秒
1.
2.
Loss of function variants in NOTCH1 cause left ventricular outflow tract obstructive defects (LVOTO). However, the risk conferred by rare and noncoding variants in NOTCH1 for LVOTO remains largely uncharacterized. In a cohort of 49 families affected by hypoplastic left heart syndrome, a severe form of LVOTO, we discovered predicted loss of function NOTCH1 variants in 6% of individuals. Rare or low-frequency missense variants were found in 16% of families. To make a quantitative estimate of the genetic risk posed by variants in NOTCH1 for LVOTO, we studied associations of 400 coding and noncoding variants in NOTCH1 in 1,085 cases and 332,788 controls from the UK Biobank. Two rare intronic variants in strong linkage disequilibrium displayed significant association with risk for LVOTO amongst European-ancestry individuals. This result was replicated in an independent analysis of 210 cases and 68,762 controls of non-European and mixed ancestry. In conclusion, carrying rare predicted loss of function variants in NOTCH1 confer significant risk for LVOTO. In addition, the two intronic variants seem to be associated with an increased risk for these defects. Our approach demonstrates the utility of population-based data sets in quantifying the specific risk of individual variants for disease-related phenotypes.  相似文献   
3.
4.
5.
6.
1. The present study aimed to determine the feasibility of conducting a 5 year cardiovascular outcome trial of the treatment of 6000 elderly hypertensive patients in Australian general practices. 2. General practitioners (GPs) were invited to participate by mail and personal follow-up. Patient records were reviewed to identify subjects for a blood pressure (BP) screening programme. Blood pressure was measured on three occasions and eligible subjects were included if the average BP was 160 mmHg systolic or 90 mmHg diastolic if systolic BP was 140 mmHg. 3. Seven hundred and forty-one GPs were approached and 89 were enrolled in the study (12% of mail invites and 75% of those receiving a personal contact). In 16 practices where screening was completed, 82 000 records were reviewed to identify 4% patients eligible for screening. Twenty-two per cent of eligible subjects attended screening. Of 1938 subjects screened, 180 (9%) had BP 5=160/90 mmHg. Forty-seven percent of subjects (n = 916) were receiving antihypertensive therapy and 184 (20%) were withdrawn from therapy. One hundred and sixteen (63%) of these subjects had BP return to study entry levels within 6 weeks. Fifty-seven newly diagnosed and 81 previously treated subjects were randomized (7% of the screened population). 4. Based on the high participation rate of GPs, the response rate of patients to attend a BP screening programme and the 7% randomization to screening ratio for entry into the study, the ANBP2 pilot study has demonstrated that it is feasible to recruit subjects from Australian general practices to a cardiovascular outcome trial.  相似文献   
7.
Ultrasound guided biopsy of the prostate with fine needle (22G) as well as trucut needle (18G) was performed in 145 patients with a suspicion of prostate cancer. After three weeks all patients were interviewed about complications associated with the biopsy. Hematuria and/or hemospermia occurred in 2/3 of the patients. None of the hemorrhages was severe and all ceased spontaneously. E. coli infection of the urinary tract occurred in 9 cases (6.2%). Five of the infections caused high fever and necessitated hospital care with parenteral antibiotics for 1 to 8 days. The patients with infection had no signs of immunological defects by which they might have been identified before the biopsy. As a consequence of these observations we now use prophylactic antibiotics when core biopsy of the prostate is performed transrectally.  相似文献   
8.
The effect of cooking time on mutagenic activity in crust, pan residue and smoke from pan-broiled pork patties was studied in the Ames Salmonella mutagenicity test system. The effect on mutagenicity of reheating the cooked patties and of keeping them warm was also studied. The meat was broiled at 200 degrees C for various times between 2 and 10 min. Broiled meat was reheated up to 5 times at 200 degrees C, each time to a centre temperature of 70 degrees C. Reheating was also performed in a microwave oven for 2 min and in an electric oven at 200 degrees C for 10 min. In addition, broiled patties were kept warm at 60 degrees C in an incubator for up to 9 hr. The mutagenic activity increased rapidly in all fractions except the volatile phase over the first 6 min of cooking, after which time only a slight increase was seen. At cooking times below 4 min no mutagenic activity was detected in the smoke. Reheating or keeping the meat warm for up to 9 hr had very little effect on the mutagenic activity of the meat. Reversed-phase high-performance liquid chromatography mutagenicity profiles of the aerosol, crust and pan-residue extracts showed no major qualitative differences in samples cooked at different times. It is concluded that during pan broiling at 200 degrees C the major part of the mutagenic activity is formed during the first 6 min of cooking. Reheating the meat or keeping it warm does not significantly affect the mutagenic activity. No major additional mutagens are formed during continued heating for up to 25 min.  相似文献   
9.
Akathisia as a side-effect of metoclopramide has received increasing attention in consultation-liaison psychiatry in recent years. A case of metoclopramide-induced akathisia resulting in a suicide attempt is reported in order to highlight the suffering of such patients and the factors that lead to misdiagnosis.  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