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   104611篇
  免费   9575篇
  国内免费   5295篇
耳鼻咽喉   1112篇
儿科学   1076篇
妇产科学   1559篇
基础医学   13510篇
口腔科学   2159篇
临床医学   11072篇
内科学   17147篇
皮肤病学   1370篇
神经病学   6272篇
特种医学   3715篇
外国民族医学   28篇
外科学   13044篇
综合类   14462篇
现状与发展   7篇
一般理论   11篇
预防医学   6979篇
眼科学   2845篇
药学   10418篇
  62篇
中国医学   4368篇
肿瘤学   8265篇
  2024年   280篇
  2023年   1147篇
  2022年   2716篇
  2021年   3583篇
  2020年   2767篇
  2019年   2453篇
  2018年   3074篇
  2017年   2643篇
  2016年   2634篇
  2015年   3611篇
  2014年   4526篇
  2013年   4701篇
  2012年   6877篇
  2011年   6918篇
  2010年   4684篇
  2009年   3968篇
  2008年   4826篇
  2007年   4857篇
  2006年   4482篇
  2005年   3896篇
  2004年   2886篇
  2003年   2681篇
  2002年   2350篇
  2001年   5441篇
  2000年   5246篇
  1999年   4635篇
  1998年   1790篇
  1997年   1429篇
  1996年   966篇
  1995年   795篇
  1994年   714篇
  1993年   565篇
  1992年   2089篇
  1991年   1814篇
  1990年   1669篇
  1989年   1596篇
  1988年   1395篇
  1987年   1282篇
  1986年   1137篇
  1985年   958篇
  1984年   632篇
  1983年   494篇
  1982年   262篇
  1981年   194篇
  1980年   154篇
  1979年   294篇
  1978年   93篇
  1974年   84篇
  1973年   103篇
  1972年   78篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
22.
The effects of some antirheumatics on the formation and retraction of collagen lattices seeded with fibroblasts have been studied. Among the antirheumatics, diclofenac was the most active inhibitor of lattice retraction, then tropesin and to a lesser extent indomethacin. Ibuprofen which is known as a very slight inhibitor of protein synthesis was able to significantly enhance lattice retraction when 10 micrograms/ml (48.5 microM) and 50 micrograms/ml (242 microM) were used.  相似文献   
23.
24.
Klippel-Feil syndrome (KFS) is a heterogeneous entity, characterized by specific congenital anomalies of segmentation of the cervical spine. We report a case of KFS plus atretic meningocele in one identical twin and anencephaly in the other. These identical twins were both male with no chromosome defect. One of them had anencephaly diagnosed at the gestational age of 17 weeks and died soon after birth, whereas the co-twin had KFS with multiple congenital anomalies including short neck with low hairline, occipital atretic meningocele, butterfly vertebrae, hemivertebrae, cervico-thoracic scoliosis, left thumb preaxial polydactyly, and right undescended testis. He received rehabilitation during infancy and could walk at the age of 15 months. Both of these infants had preaxial polydactyly, which is an uncommon anomaly associated with KFS. In conclusion, iniencephaly and anencephaly are probably the extreme manifestations of KFS rather than different dysraphisms. Prompt clinical suspicion with early diagnostic imaging for spine lesions and occult opening of neural tube is mandatory for further intervention and rehabilitation.  相似文献   
25.
26.
There are several possible determinants of obesity, including impaired thermogenesis and the differential utilization of fuels in different tissues. Whereas hypometabolism may initiate obesity in some people, once obese, individuals tend to manifest a higher resting metabolic rate because of their greater fat-free mass, exhibit an impaired thermic response to food, and expend more calories than lean individuals for equivalent amounts of activity. As a result, over a 24-h period, obese people generally expend more energy than lean people. A second determinant of obesity is related to fuel utilization and suggests that those predisposed to be obese may have an innate insulin resistance in muscle, leading to decreased uptake, oxidation, and storage of glucose in this tissue. As a result, the glucose is shunted to adipose tissue, where it is stored. With regard to treatment of obesity, emphasis on increased energy expenditure through the inclusion of reasonable amounts of activity is essential. However, this must always be combined with restraint in caloric intake.  相似文献   
27.
Sixteen patients underwent surgical treatment for severe renovascular hypertension with rapidly progressive renal failure. These patients were assessed preoperatively with the measurement of serum creatinine and blood-urea levels (means 271 +/- 204 mumol/l and 15.6 +/- 10.3 mmol/l respectively), and renal clearances. 5 patients underwent aorto-renal bypass (bilateral in one case) and 11 patients were treated by autotransplantation of the kidney. Operative mortality was 6.2%. Early results were assessed at 1 and 6 months postoperatively. Renal function was normal in 8 patients, improved in 5 (p less than 0.05), unchanged in 1 and worse in 1 by aorto-renal bypass thrombosis. At long-term with a minimum follow-up of 12 months (mean 31 +/- 12 months), the initial improvement in renal function remained steady in 12 patients whilst 1 patient has gone on to hemodialysis. At middle and long-term, 81% of the patients were normotensive without medication or had improved blood pressure (p less than 0.001). These good results confirm the reversibility of renal ischemic lesions and support an aggressive attitude towards the use of revascularization in the surgical treatment of such patients with renovascular hypertension and renal failure.  相似文献   
28.
An indirect enzyme-linked immunosorbent assay (ELISA) for the detection of hexoestrol (HES) was developed, optimized and validated for the analysis of HES in pork. Many parameters, such as the volume ratio of solution A and solution B, colour developing time, pH value, incubation time, the volume ratio of the standard solution and diluted antiserum, blocking solution, blocking condition, coating solution and coating condition were studied and optimized in the paper. The regression equation of the final inhibition curve is y = - 0.3345x + 1.4955, R2=0.9913. The linear range is 0.1-8.1 ng/ml, and the IC50 is 0.671 ng/ml. The specificity of the assay was evaluated by the cross-reactivity rates of six compounds, of which two structurally related compounds had a relatively higher cross-reactivity rate of 25% and 6%. HES was added into a pork sample at 5 ng/g level and then the sample was extracted. The recovery is between 49.6% and 79.2%, and the variation coefficient is 0.164.  相似文献   
29.
30.
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