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   223篇
  免费   6篇
  国内免费   2篇
儿科学   12篇
妇产科学   1篇
基础医学   19篇
口腔科学   3篇
临床医学   15篇
内科学   86篇
皮肤病学   2篇
神经病学   12篇
特种医学   35篇
外科学   12篇
综合类   1篇
预防医学   16篇
眼科学   2篇
药学   5篇
肿瘤学   10篇
  2022年   2篇
  2019年   2篇
  2017年   2篇
  2016年   1篇
  2015年   2篇
  2014年   6篇
  2013年   8篇
  2012年   2篇
  2011年   3篇
  2010年   6篇
  2009年   3篇
  2008年   6篇
  2007年   5篇
  2006年   6篇
  2005年   13篇
  2003年   3篇
  2001年   5篇
  2000年   3篇
  1999年   4篇
  1998年   6篇
  1997年   10篇
  1996年   17篇
  1995年   12篇
  1994年   11篇
  1993年   12篇
  1992年   3篇
  1990年   2篇
  1989年   10篇
  1988年   10篇
  1987年   8篇
  1986年   6篇
  1985年   7篇
  1984年   5篇
  1983年   4篇
  1981年   4篇
  1980年   5篇
  1979年   2篇
  1978年   3篇
  1977年   2篇
  1976年   2篇
  1975年   2篇
  1959年   2篇
  1954年   1篇
  1949年   1篇
  1931年   1篇
  1889年   1篇
排序方式: 共有231条查询结果,搜索用时 31 毫秒
71.
The long-term consequences of a physiological-range increase of maternal corticosterone during lactation were investigated on the 15-month-old progeny. The offspring of rats drinking water supplemented with corticosterone (200 microgram/ml of corticosterone hemisuccinate) from day 1 postpartum to weaning exhibited: (i) better performance in a conditioned learning test; (ii) reduction of fearfulness in two conflict situations; (iii) lower stress-induced corticosterone secretion and (iv) higher number of corticosteroid receptors in the hippocampus. The results of this study show that the effects of maternal physiological-range hypercorticosteronemia during lactation are lifelong. Moreover, these data suggest that corticosteroids, secreted during neonatal life, may constitute a factor directing the neurobiological development of the infant. In line with this hypothesis, glucocorticoid-induced early events have consequences on the behavioral and physiological status of adulthood. These consequences may be either "beneficial" or "detrimental" depending on the plasma levels of corticosterone induced by the early life occurrences, as well as on the kind of the stimulus and the developmental stage at which the neonate experiences the event. The present study demonstrates that, when the increase of corticosterone in infancy is moderate, the adult rats show reduced anxiety, improved learning and a better coping strategy to deal with stressful situations.  相似文献   
72.
73.
OBJECTIVE: Aim of the present study was to examine the adrenocortical activity in basal condition and following a mild stress exposure in long-term HRT-treated menopausal women. Menopausal women, long term users of HRT (14 subjects) were compared both to menopausal women who had never used HRT (14 subjects) and young pre-menopausal women (14 subjects). STUDY DESIGN: Morning and evening salivary cortisol secretion was measured in samples collected twice a day (08:00 in the morning and 08:00 in the evening). Mild stress response was evoked by administration of the Stroop color-word test (CWT). Salivary cortisol was measured immediately before the start, 15, 30 and 45 min after the completion of the test. RESULTS: Menopause appears not to be associated with an impairment of cortisol circadian fluctuation. Long-term use of HRT in menopause attenuated HPA activity either in basal condition or in response to mild stress exposure. With regard to the CWT performance, all menopausal women took significantly longer than young women to perform the test. However, long-term HRT significantly reduced the number of errors made during the test. CONCLUSIONS: The present study suggested that long-term HRT could help menopausal patients to cope with mild stress and to improve mental performances.  相似文献   
74.
75.
PURPOSE: Most children with a diffuse intrinsic brainstem glioma will die within 1 year after diagnosis. To reduce patient burden, we investigated the feasibility of a radical hypofractionation radiotherapy schedule, given over 3 weeks, as an alternative to the standard regimen (30 fractions over 6 weeks). METHODS AND MATERIALS: Nine children, ages 3-13, were treated by 13 fractions of 3 Gy (n = 8) or 6 fractions of 5.5 Gy (n = 1) given over 3 weeks. All patients had symptoms for ≤3 months and ≥2 signs of the neurologic triad (long tract signs, ataxia, cranial nerve deficit). Bilateral involvement of the pons (n = 8), encasement of the basilar artery (n = 7) and extension into the eerebellar peduncle (n = 6) was visible on magnetic resonance imaging.  相似文献   
76.
77.
A good result was achieved by treating ureteric perforation conservatively following ureteroscopy.  相似文献   
78.
The ultimate fate of T cells undergoing antigen-induced cell death in vivo remains controversial. Whereas apoptosis of CD4+ T cells driven by superantigen is readily detectable in lymphoid organs, CD8+ T cells have been reported to disappear from the lymphoid organs and accumulate in the liver where they undergo apoptosis. Using transgenic mice that produce large numbers of ovalbumin-specific CD8+ T cells (OT-I cells), we were able to investigate the events that follow soluble peptide administration in an independent CD8+ T cell system. Here we show that the OT-I cells undergo proliferation and apoptosis in situ in lymphoid organs in response to antigenic stimulation with no evidence for liver involvement. This is similar to the course of events found for CD4+ T cell activation and counters the view that the liver is a general site for CD8+ T cell clearance following antigen-specific activation.   相似文献   
79.
Tetralogy of Fallot: MR findings   总被引:2,自引:0,他引:2  
Surgical treatment of patients with tetralogy of Fallot requires accurate definition of all anatomic structures, particularly the central pulmonary arteries. Magnetic resonance (MR) images of 22 patients with tetralogy of Fallot were studied to assess their usefulness in providing information regarding the spectrum of anatomic abnormalities in this condition. MR findings were compared with information obtained at catheterization (in 16 patients) and at surgery (in nine patients), both of which were performed within 3 months of MR imaging. Ventricular chamber enlargement and wall hypertrophy were clearly delineated in most of the 17 patients who were examined before definitive surgical repair, and ventricular septal defects were visualized in all 17. Palliative systemic-to-pulmonary shunts were visualized in 11 patients and could be evaluated for patency. Most important, the morphology and size of the right ventricular outflow tract and central pulmonary arteries could be accurately assessed. Pulmonary artery measurements obtained from MR images demonstrated excellent correlation with angiographic measurements. In six patients examined after complete surgical repair, MR images accurately reflected changes in pulmonary artery outflow tract morphology and complications, such as residual pulmonary artery stenosis and thrombosis. The findings suggest that MR imaging can complement or obviate catheterization in the evaluation of tetralogy of Fallot with regard to suitability for definitive surgical repair.  相似文献   
80.
Matzinger  FR; Ho  CS; Yee  AC; Gray  RR 《Radiology》1988,167(2):431-434
Percutaneous transgastric placement of a drainage catheter under ultrasonographic and fluoroscopic guidance was performed in 12 patients with pancreatic pseudocysts. Complete resolution of the pseudocysts was obtained in eight patients, and the result was indeterminate in one patient due to early death from unrelated causes. Surgical intervention followed in two patients, one with a multiloculated pseudocyst that was incompletely drained and another with a pseudocyst that became infected following drainage. In one patient with metastatic tumor to the head of the pancreas the pseudocyst resolved initially, but a pseudocyst later recurred. There were no pancreaticocutaneous fistulas or other major complications. The transgastric route of pseudocyst drainage is safe and effective, and it offers a low risk of recurrence and fistula formation.  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