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   552篇
  免费   49篇
  国内免费   23篇
耳鼻咽喉   5篇
儿科学   28篇
妇产科学   6篇
基础医学   85篇
口腔科学   9篇
临床医学   57篇
内科学   126篇
皮肤病学   40篇
神经病学   47篇
特种医学   72篇
外科学   35篇
综合类   17篇
一般理论   1篇
预防医学   23篇
眼科学   2篇
药学   42篇
肿瘤学   29篇
  2023年   2篇
  2022年   3篇
  2021年   9篇
  2020年   4篇
  2019年   10篇
  2018年   9篇
  2017年   8篇
  2016年   8篇
  2015年   14篇
  2014年   12篇
  2013年   17篇
  2012年   16篇
  2011年   20篇
  2010年   22篇
  2009年   26篇
  2008年   18篇
  2007年   28篇
  2006年   19篇
  2005年   20篇
  2004年   15篇
  2003年   20篇
  2002年   21篇
  2001年   17篇
  2000年   8篇
  1999年   17篇
  1998年   31篇
  1997年   17篇
  1996年   30篇
  1995年   10篇
  1994年   20篇
  1993年   9篇
  1992年   7篇
  1991年   8篇
  1990年   14篇
  1989年   11篇
  1988年   18篇
  1987年   12篇
  1986年   8篇
  1985年   14篇
  1984年   5篇
  1983年   7篇
  1982年   6篇
  1981年   6篇
  1980年   7篇
  1979年   2篇
  1978年   5篇
  1977年   4篇
  1976年   6篇
  1975年   3篇
  1967年   1篇
排序方式: 共有624条查询结果,搜索用时 15 毫秒
1.
Pityriasis rosea (PR) is a relatively common disease although its aetiology has not yet been identified. It occurs worldwide and there is no racial susceptibility factor. It usually affects teenagers and young adults between 10 and 35 years of age. Typical PR is much easier to diagnose than the rare atypical forms. We report a rare case of vesicular PR in a black woman who had vesicular lesions limited to her palms and soles in addition to regular typical lesions. We devised an efficient oral erythromycin treatment for this patient.  相似文献   
2.
Epidemiological study of myasthenia gravis in Sardinia, Italy (1958–1986)   总被引:2,自引:0,他引:2  
From 1.1.1958 to 31.12.1986, 110 cases of MG were observed in Sardinia, with a mean annual incidence of 2.5 x 1,000,000 inhabitants and prevalence rates of 7.5, 17.6, 31.4 and 45.0 x 1,000,000 inhabitants respectively (prevalence days: 15.10.1961, 24.10.1971, 25.10.1981 and 31.12.1986). The disease was found to be more frequent in women. There were no differences in the distribution of MG in various areas of the island. The muscle group more frequently involved at onset was the ocular. In 6.4% of patients an association with thyroid disorders was observed. The mortality of MG patients was significantly higher than expected. Removal of the thymus, carried out in 58 patients, was shown to be useful in the treatment of the disease, particularly in patients without thymomas. No familial cases were observed.  相似文献   
3.
4.
5.
6.
7.
进一步研究了抗三尖杉酯碱的HL-60细胞(HR20)抗细胞凋亡的机制及该抗性和抗药性的关系。结果表明,环孢菌素A(CsA)20,10μg·ml ̄(-1)诱导HL-60细胞发生凋亡,而阻断HR20细胞于G_1期,就不能诱导细胞发生凋亡。低浓度的CsA明显增加柔红霉素在HR20细胞内的积聚,其逆转抗药性作用与阻断细胞周期运行无关。CsA10μg·ml ̄(-1)处理HR20细胞,可引起50kDa的蛋白质高度磷酸化。结果提示:环孢菌素A阻断抗三尖杉酯碱的HL-60细胞于G_1期,而诱导敏感的HL-60细胞发生凋亡,其阻断作用与抗药性无关  相似文献   
8.
The systematic screening of 253 children with transfusion-dependent homozygous beta-thalassaemia revealed a high incidence of hepatitis B virus markers. The highest frequencies of hepatitis B surface antigen (HBsAg) and antibody to hepatitis B core antigen (anti-HBc) were found in the group of patients with the smallest number of transfusions, while the highest frequency of antibody to hepatitis B surface antigen (anti-HBs) was detected in the patients who had had the largest number of transfusions. Follow-up of these patients showed (a) a high incidence of acute hepatitis B, which was mainly subclinical; (b) normal hepatitis B surface antigen clearance and normal antibody to hepatitis B surface development; and (c) a high frequency of increased transaminase values for over six months. In all the subjects with persistently high transaminase, histological examination revealed chronic persistent hepatitis or chronic active hepatitis. Apart from two cases of chronic active hepatitis with no B virus markers, and two cases of chronic persistent hepatitis with HBsAg and anti-HBc in the serum, all these subjects were anti-HBs positive but HGsAg and anti-HBc negative.  相似文献   
9.
Uncertainties regarding the pathogenetic changes underlying the polycystic ovarian syndrome (PCOS) have been reported. The aim of this study was to investigate the endocrine and metabolic features of PCOS patients in relation to luteinizing hormone (LH) secretion. Androgen assays, oral glucose tolerance tests, hyperinsulinaemic euglycaemic clamps and gonadotrophin releasing hormone (GnRH) tests were performed in 100 patients. Sixty-six patients scheduled as hyperinsulinaemic and 34 as normoinsulinaemic showed similar concentrations of LH, follicle stimulating hormone (FSH), LH/FSH ratio, and LH response to GnRH testing. Hyperinsulinaemic subjects showed higher body mass index (BMI), insulin resistance, testosterone and free androgen index levels compared with those of normoinsulinaemic subjects; when clustered in relation to their LH basal concentrations, the two groups obtained differed only in androstenedione concentrations. Considering both insulin and LH plasma concentrations, four groups were obtained. Hyperinsulinaemia and hyper-LH secretion were not related in 54% and coexisted in the same subjects in 26% of cases. Hyperinsulinaemia as well as hyper-LH secretion affected the expression of the syndrome; the insulinaemia was directly correlated with testosterone concentrations and all metabolic parameters that affected the free androgen index. The LH concentrations were related to androgen production and were independent of BMI and insulin concentrations. It is concluded that the degree of hormonal alteration is the final sum of such pathogenetic factors.  相似文献   
10.
Needle biopsy of renal allografts: comparison of two techniques   总被引:2,自引:0,他引:2  
Two techniques for renal allograft biopsy were retrospectively evaluated to compare relative safety and efficacy. After ultrasound (US) localization of the kidney and biopsy with a hand-held 14-gauge cutting needle, an adequate specimen was obtained in 74 of 77 cases (96%). Major complications occurred in six of these 77 cases (8%). One hundred four biopsies were performed by using a smaller 18-gauge cutting needle with a spring-loaded biopsy "gun" and real-time US guidance. With this newer technique, specimens adequate for diagnosis were obtained in 99 biopsies (95%). There was a single major complication with this technique (1%). The 18-gauge needle with real-time US guidance yields comparably adequate specimens with a lower frequency of complications.  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