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   2286800篇
  免费   167737篇
  国内免费   3356篇
耳鼻咽喉   31601篇
儿科学   75605篇
妇产科学   65743篇
基础医学   336558篇
口腔科学   64495篇
临床医学   205160篇
内科学   443882篇
皮肤病学   48468篇
神经病学   181399篇
特种医学   87286篇
外国民族医学   602篇
外科学   338900篇
综合类   48223篇
现状与发展   4篇
一般理论   823篇
预防医学   180010篇
眼科学   52254篇
药学   171321篇
  8篇
中国医学   4091篇
肿瘤学   121460篇
  2018年   22776篇
  2016年   19168篇
  2015年   22260篇
  2014年   30746篇
  2013年   47000篇
  2012年   64221篇
  2011年   68632篇
  2010年   40133篇
  2009年   38307篇
  2008年   65555篇
  2007年   70562篇
  2006年   70899篇
  2005年   69491篇
  2004年   66894篇
  2003年   64309篇
  2002年   63022篇
  2001年   100043篇
  2000年   102481篇
  1999年   86857篇
  1998年   24994篇
  1997年   22432篇
  1996年   22893篇
  1995年   21718篇
  1994年   20473篇
  1993年   18968篇
  1992年   69983篇
  1991年   69020篇
  1990年   67735篇
  1989年   65640篇
  1988年   61152篇
  1987年   60050篇
  1986年   57287篇
  1985年   54523篇
  1984年   41106篇
  1983年   35795篇
  1982年   21441篇
  1981年   19297篇
  1979年   39447篇
  1978年   28322篇
  1977年   24072篇
  1976年   22564篇
  1975年   24596篇
  1974年   29442篇
  1973年   28674篇
  1972年   27208篇
  1971年   25374篇
  1970年   23766篇
  1969年   22714篇
  1968年   21287篇
  1967年   18960篇
排序方式: 共有10000条查询结果,搜索用时 12 毫秒
51.
Background The objective was to measure the plasma concentrations of thymulin and nerve growth factor (NGF) in a group of patients with primary open angle glaucoma (POAG) and compare them with age- and sex-matched normal controls.Methods Twenty-eight patients newly diagnosed with POAG who were not undergoing treatment were compared with the same number of age- and sex-matched healthy controls. Blood samples were drawn into heparinized tubes and plasma samples were collected for the determination of the concentrations of thymulin and NGF, using specific enzyme-linked immunosorbent assay (ELISA). The Student’s t test was used to perform the necessary statistical analysis of the results.Results Seventeen women and 11 men were enrolled in each of the two groups (study and control), with a mean age of 63.7 (SD 10.3) years in the former and 63.3 (SD 9.6) years in the latter. There was a highly significant (p<0.001) elevation in the thymulin levels in POAG patients compared with the control group. However, no significant difference was observed when comparing the plasma NGF levels.Conclusion This is the first report to measure plasma thymulin levels in glaucoma patients. The significant results point the possible role of this immunomodulator in the pathogenesis of primary open angle glaucoma. The potential role of NGF seems to be less likely. These findings warrant further investigation.  相似文献   
52.
PURPOSE: To determine the maximum tolerated dose, dose-limiting toxicities, and pharmacokinetic characteristics of doxorubicin encapsulated in a low temperature sensitive liposome (LTSL) when given concurrently with local hyperthermia to canine solid tumors. EXPERIMENTAL DESIGN: Privately owned dogs with solid tumors (carcinomas or sarcomas) were treated. The tumors did not involve bone and were located at sites amenable to local hyperthermia. LTSL-doxorubicin was given (0.7-1.0 mg/kg i.v.) over 30 minutes during local tumor hyperthermia in a standard phase I dose escalation study. Three treatments, given 3 weeks apart, were scheduled. Toxicity was monitored for an additional month. Pharmacokinetics were evaluated during the first treatment cycle. RESULTS: Twenty-one patients were enrolled: 18 with sarcomas and 3 with carcinomas. Grade 4 neutropenia and acute death secondary to liver failure, possibly drug related, were the dose-limiting toxicities. The maximum tolerated dose was 0.93 mg/kg. Other toxicities, with the possible exception of renal damage, were consistent with those observed following free doxorubicin administration. Of the 20 dogs that received > or = 2 doses of LTSL-doxorubicin, 12 had stable disease, and 6 had a partial response to treatment. Pharmacokinetic variables were more similar to those of free doxorubicin than the marketed liposomal product. Tumor drug concentrations at a dose of 1.0 mg/kg averaged 9.12 +/- 6.17 ng/mg tissue. CONCLUSION: LTSL-doxorubicin offers a novel approach to improving drug delivery to solid tumors. It was well tolerated and resulted in favorable response profiles in these patients. Additional evaluation in human patients is warranted.  相似文献   
53.
54.
55.
We report the case of a 38-year-old woman who presented with chronic lower abdominal pain. Her past medical history included a splenectomy due to abdominal trauma. Ultrasound examination revealed four pelvic tumors which, upon laparotomy, were found to be the result of splenosis. Approximately 100 cases of splenosis have been reported but only a minority of them have been published in the gynecological literature. Our case indicates that those involved in pelvic scanning (even of asymptomatic women) and/or treating those complaining of lower abdominal pain or presenting with pelvic tumors should be aware of splenosis as a possible diagnosis.  相似文献   
56.
57.
58.
59.
60.
Neu-Laxova syndrome (NLS) is a rare autosomal recessive syndrome, characterized by severe intrauterine growth retardation (IUGR), microcephaly, abnormal brain development, oedema and ichthyosis. It was first reported in 1971 by Neu et al. (Pediatrics 47: 610-612) and since then no more than 60 cases have been reported. A newborn girl delivered from a 29-year-old healthy mother was admitted to hospital with a thick membrane covering her body and dismorphic appearance. The diagnosis of NLS was made according to characteristic features. The syndrome is known to have a poor prognosis and the baby lived for 9 weeks. This case is one of the longest living cases of NLS and the fourth case reported from Turkey.  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