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   660篇
  免费   44篇
  国内免费   2篇
耳鼻咽喉   2篇
儿科学   29篇
妇产科学   15篇
基础医学   84篇
口腔科学   2篇
临床医学   33篇
内科学   99篇
皮肤病学   2篇
神经病学   129篇
特种医学   10篇
外科学   64篇
综合类   2篇
预防医学   95篇
眼科学   1篇
药学   98篇
肿瘤学   41篇
  2023年   4篇
  2022年   5篇
  2021年   5篇
  2020年   9篇
  2018年   11篇
  2017年   11篇
  2016年   17篇
  2015年   21篇
  2014年   22篇
  2013年   26篇
  2012年   48篇
  2011年   54篇
  2010年   26篇
  2009年   13篇
  2008年   28篇
  2007年   29篇
  2006年   28篇
  2005年   23篇
  2004年   29篇
  2003年   21篇
  2002年   20篇
  2001年   14篇
  2000年   15篇
  1999年   14篇
  1997年   8篇
  1995年   7篇
  1992年   10篇
  1991年   9篇
  1990年   13篇
  1989年   12篇
  1988年   14篇
  1987年   12篇
  1986年   11篇
  1985年   6篇
  1984年   6篇
  1983年   9篇
  1982年   3篇
  1981年   5篇
  1980年   4篇
  1978年   3篇
  1977年   5篇
  1975年   4篇
  1974年   8篇
  1973年   5篇
  1972年   6篇
  1971年   9篇
  1970年   3篇
  1968年   5篇
  1966年   8篇
  1964年   3篇
排序方式: 共有706条查询结果,搜索用时 375 毫秒
1.
Several substances can interfere with microtubular function eg. colchicine. Melatonin, a hormone secreted by the pineal gland has similar effects as colchicine on microtubules. In this study melatonin levels were determined in both plasma and seminal plasma of patients with good or impaired motility and forward progression. There was no statistically significant difference between the mean plasma and seminal plasma values of patients with good or impaired motility and forward progression. There was no correlation between seminal plasma melatonin and impaired motility or any other semen parameter. There was also no correlation between plasma and seminal plasma concentrations of melatonin. High seminal plasma melatonin concentrations were not necessarily associated with impaired sperm motility. From these it is concluded that seminal plasma melatonin plays no important role in sperm motility.  相似文献   
2.
We have previously demonstrated in a rat model that the lumbar intrathecal injection of 0.02 ml 6.3% magnesium sulphate, a concentration iso-osmolar with rat plasma, produces a state of spinal anaesthesia and general sedation which reversed completely after 6 h, without evidence of neurotoxicity, immediately or during the week thereafter. Using the same model and five groups of six animals in each, we administered the same volume and concentration of magnesium sulphate and compared its clinical effects with those of 0.02 ml 12.6% magnesium sulphate, 0.02 ml 2% lignocaine and 0.02 ml 0.9% sodium chloride solution, given as a series of 15 injections on alternate days for a period of 1 month. The animals were then killed and their spinal cords and meninges examined histologically. No significant differences were noted in the times of onset, durations of sensory and motor blockade and the times to full recovery throughout the entire period of 1 month's observation in the animals receiving intrathecal 6.3% magnesium sulphate. In the group receiving 12.6% magnesium sulphate, the time of onset of sensory and motor blockade was shorter and the duration of both parameters was significantly longer than in the former group. Full clinical recovery and resumption of normal eating and drinking took place in both groups throughout the entire series of 15 successive intrathecal injections. Identical, mild, uniform histopathological changes in the spinal cord were seen in all the five groups, including the group in which only the intrathecal catheter was implanted. The complete recovery and benign consequences of repeated intrathecal injections of iso-osmolar magnesium sulphate in a rat model indicate a lack of neurotoxicity and provide an impetus for further trials in larger animal species, before initial clinical trials of this substance, given intrathecally, in humans.  相似文献   
3.
Comparative trial of sclerotherapy for hydroceles   总被引:1,自引:0,他引:1  
We present a prospective single-blind trial of sclerotherapy for hydroceles with tetradecyl sulphate and rolitetracycline as sclerosants. Twenty-seven hydroceles were treated with tetradecyl sulphate and 28 with rolitetracycline. The median follow-up was 13 months. There were no statistically significant differences between the 2 drugs in respect of cure rate and complications. The overall cure rate for both drugs was 96%. Complications were rare and common to both drugs. Tetradecyl sulphate and rolitetracycline were found to be equally effective as sclerosants.  相似文献   
4.
5.
6.
A mathematically defined extension of Landsteiner's concept of serological specificity is given. It is a general method that compares the relative specificity of two antisera. The resultant comparison is independent of the relative potencies of the antisera. It is valid for antisera prepared either against pure antigens or against mixtures of antigens.

The method has been applied to data taken from the literature, involving haemagglutination, precipitin and enzyme reactions, and to new experimental data. Rabbit antisera were prepared against mouse erythrocytes and lymphocytes, and against three mouse ascites tumours. The potencies of these unabsorbed antisera were determined by immune cytolysis against each of these cell types. All antisera possessed moderate to strong cytolytic potencies against all mouse cells tested, but showed only low to moderate specificities.

  相似文献   
7.
Two brothers with severe and rare lower limb malformations but normal upper limbs are described. Both brothers had glans hypospadias and they died in early infancy. In the first brother the limb malformation was a severe deformity of the right foot which was split and of rockerbottom shape with oligosyndactyly. In the second brother the right limb below the knee was more severely deformed while only the toes were involved in the left limb. Details of the clinical and pathological findings are described. The most likely mode of inheritance of this rare syndrome is autosomal recessive or X-linked recessive with variable expressivity.  相似文献   
8.
Six tumors of varying immunorejective strengths were used to compare the response of their isogenic hosts to standardized regimens of immunoprophylaxis and immunotherapy. The tumors were generated spontaneously or induced chemically [with 9,10-dimethyl-1,2-benzanthracene (CAS: 57-97-6)], virally (with murine leukemia virus), or radiogenically (with strontium-90). The hosts were C57BL/6J or BALB/cByJ mice. Immunoprophylaxis and immunotherapy were performed with isogenic irradiated tumor cells, with Corynebacterium parvum, or with both. The results of challenge experiments were quantified as the doses of viable tumor cells that produced 50% tumor deaths for immunized and for control mice. The results for these quantitative "classical" immunoprophylaxis and immunotherapy experiments were consistent with two theses: that only immunorejective tumors give positive results with classical immunotherapy and that classical immunoprophylaxis is more effective than classical immunotherapy when identical materials are used for immunizations. These results have important consequences for the clinical use of classical immunotherapy.  相似文献   
9.
Drolshagen  H.  Bhavaraju  A.  Kalkwarf  K. J.  Karim  S. A.  Reif  R.  Sexton  K. W.  Jensen  H. K. 《Hernia》2021,25(5):1259-1264
Hernia - Inguinal hernia repair is one of the most common surgical operations, yet the optimal treatment strategy remains undefined. Treatment of symptomatic inguinal hernias include both surgical...  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