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   568篇
  免费   18篇
  国内免费   21篇
耳鼻咽喉   1篇
儿科学   25篇
妇产科学   6篇
基础医学   58篇
口腔科学   30篇
临床医学   33篇
内科学   94篇
皮肤病学   58篇
神经病学   9篇
特种医学   97篇
外科学   58篇
综合类   49篇
预防医学   22篇
眼科学   6篇
药学   41篇
肿瘤学   20篇
  2022年   3篇
  2021年   5篇
  2020年   2篇
  2019年   3篇
  2018年   8篇
  2017年   5篇
  2016年   2篇
  2015年   12篇
  2014年   9篇
  2013年   22篇
  2012年   9篇
  2011年   13篇
  2010年   25篇
  2009年   26篇
  2008年   11篇
  2007年   34篇
  2006年   30篇
  2005年   16篇
  2004年   26篇
  2003年   17篇
  2002年   10篇
  2001年   12篇
  2000年   7篇
  1999年   9篇
  1998年   27篇
  1997年   34篇
  1996年   40篇
  1995年   21篇
  1994年   12篇
  1993年   20篇
  1992年   7篇
  1991年   4篇
  1990年   3篇
  1989年   21篇
  1988年   10篇
  1987年   14篇
  1986年   10篇
  1985年   10篇
  1984年   9篇
  1983年   5篇
  1982年   5篇
  1981年   5篇
  1980年   10篇
  1979年   3篇
  1978年   3篇
  1977年   5篇
  1976年   5篇
  1975年   5篇
  1962年   1篇
  1935年   1篇
排序方式: 共有607条查询结果,搜索用时 234 毫秒
91.
BACKGROUND.: The effectiveness of health promotion activity in general practiceon risk factor reduction for coronary heart disease remainsthe subject of active debate. OBJECTIVE.: The study aimed to assess the impact of practice-based healthcheck-ups on health behaviours over a 2-year period. METHOD.: A general practice cohort of 7123 patients from 18 practiceswas surveyed. Eight hundred and forty (12%) patients had beenoffered a heafth check within a 12-month period from September1992 and 621 (9%) received one. Two hundred and fifty patients(40%) were asked back for follow-up after their health check. RESULTS.: Over a 2-year period there was no difference in smoking cessation,alcohol consumption, weight loss nor the amount of exercisetaken between those who attended for a health check and thosewho did not. The food score chosen to assess dietary change(Oxcheck) showed a statistically significant 1.16-point risefor the whole sample over the survey period. There was a significantdifference in mean food score change between heafth check attendersand non-attenders (Mann-Whitney U test: P << 0.002). Maintenanceof dietary improvement over a 2-year period was not affectedby health check attendance. CONCLUSIONS.: This study confirms the low impact of health checks on the selfreported modification of cardiovascular risk factors and showsthat maintenance of appropriate health behaviour change is nomore likely in those who have received a health check. Keywords. Health promotion, general practice.  相似文献   
92.
The objectives were to determine quantitative liver function prospectively in patients with rheumatoid arthritis (RA) treated with low-dose methotrexate (MTX), to search for risk factors for a loss of quantitative liver function and to assess the relationship between quantitative liver function and histological staging. A total of 117 patients with RA (ACR criteria, 85 women, mean age 59 yr) had measurements of galactose elimination capacity (GEC), aminopyrine breath test (ABT) and liver enzymes [aspartate amino transferase (AST), alanine amino transferase (ALT), alkaline phosphatase (AP), 7-glutamyl transferase (GGT), bile acids, bilirubin, albumin] before treatment with weekly i.m. MTX injections and every year thereafter. In 16 patients, liver biopsies were performed. Before the introduction of MTX, mean GEC was 6.6 mg/min/kg [5th to 95th percentile (5-95 PC) 5.1- 8.5; reference range 6.0-9.1] and mean ABT was 0.80% kg/mmol (5-95 PC 0.42-1.30: reference range 0.6-1.0). During treatment with MTX [mean weekly dose 11.8 mg (5-95 PC 5.4-20.2), mean observation period 3.8 yr (5-95 PC 0.4-6.9)], significant declines of GEC (-0.12 mg/min/kg per year. t = 3.30, P < 0.002) and ABT (-0.06% kg/mmol per year, t = 4.81, P < 0.001) were observed. Negative correlations were found between the annual change in GEC and GEC at baseline (Rs = -0.40, P < 0.0001), and the annual change in ABT and ABT at baseline (Rs = -0.43, P < 0.0001). No correlations were found between the annual change in GEC or ABT and weekly MTX dose, age or percentage of increased liver enzymes, and no effect of a history of alcohol consumption > 30 g/week became evident. Two patients with Roenigk grade III had impaired quantitative liver function, while 14 patients with Roenigk grades I and II exhibited a high variability of GEC and ABT from normal to abnormal values. The continuous declines in GEC and ABT observed deserve attention in patients with prolonged treatment. Patients with a low GEC or ABT at baseline seem not to be at increased risk for a further loss of quantitative liver function. An impaired GEC or ABT does not necessarily concur with hepatic fibrosis on histological examination.   相似文献   
93.
Computed tomographic detection of nonbeta pancreatic islet cell tumors   总被引:6,自引:0,他引:6  
  相似文献   
94.
Ganti  SR; Antunes  JL; Louis  KM; Hilal  SK 《Radiology》1981,138(2):385
  相似文献   
95.
96.
97.
Acoustic analysis of gradient-coil noise in MR imaging   总被引:4,自引:0,他引:4  
Hurwitz  R; Lane  SR; Bell  RA; Brant-Zawadzki  MN 《Radiology》1989,173(2):545-548
A survey was conducted of acoustic noise levels in magnetic resonance (MR) imaging systems. Static magnetic flux and radio-frequency pulses did not affect the function of shielded sound-pressure detection equipment. Noise levels were measured at bore isocenter during a variety of imaging sequences in six MR imaging systems with magnetic fields of 0.35-1.5 T. Measured noise ranged from 82 to 93 dB on the A-weighted scale and from 84 to 103 dB on the linear scale. Noise levels increased during sequences employing thinner section thickness and shorter repetition and echo times and were independent of field strength. Gradient-coil noise in MR imaging is an annoyance but is well within safety guidelines.  相似文献   
98.
Antegrade internal ureteral stenting: a technical refinement   总被引:2,自引:0,他引:2  
Hackethorn  JC; Boren  SR; Dotter  CT; Rosch  J 《Radiology》1985,156(3):827-828
A pliable, easy to place, double pigtail, internal ureteral stent made of elastomeric polyurethane is described. The tapered distal pigtail end minimizes bladder irritation and the combination of a pusher and absorbable suture enables optimal placement of the proximal pigtail end in the renal pelvis. Ten stents used in eight patients remained functional without bladder irritation for a mean period of 8 months (range, 2-14 months).  相似文献   
99.
100.
Maloney  JJ; Cho  SR 《Radiology》1983,148(2):388
  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