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   448篇
  免费   14篇
  国内免费   1篇
耳鼻咽喉   3篇
儿科学   8篇
妇产科学   12篇
基础医学   34篇
口腔科学   85篇
临床医学   31篇
内科学   78篇
皮肤病学   15篇
神经病学   26篇
特种医学   15篇
外国民族医学   1篇
外科学   78篇
综合类   2篇
预防医学   10篇
眼科学   36篇
药学   21篇
肿瘤学   8篇
  2022年   5篇
  2021年   18篇
  2020年   6篇
  2019年   6篇
  2018年   12篇
  2017年   10篇
  2016年   8篇
  2015年   7篇
  2014年   11篇
  2013年   17篇
  2012年   14篇
  2011年   24篇
  2010年   3篇
  2009年   13篇
  2008年   20篇
  2007年   21篇
  2006年   15篇
  2005年   30篇
  2004年   25篇
  2003年   27篇
  2002年   19篇
  2001年   13篇
  2000年   9篇
  1999年   4篇
  1998年   4篇
  1996年   2篇
  1992年   7篇
  1991年   6篇
  1990年   4篇
  1989年   3篇
  1988年   6篇
  1987年   4篇
  1986年   10篇
  1985年   7篇
  1982年   2篇
  1981年   3篇
  1980年   1篇
  1978年   3篇
  1977年   3篇
  1975年   1篇
  1974年   3篇
  1973年   1篇
  1972年   2篇
  1971年   4篇
  1970年   7篇
  1969年   12篇
  1968年   6篇
  1967年   10篇
  1966年   9篇
  1965年   3篇
排序方式: 共有463条查询结果,搜索用时 15 毫秒
1.
2.
3.
Fluid balance assessment is a fundamental aspect of caring for critically ill patients who often have volume disturbances. Since the introduction of hemodynamic monitoring in the critical care setting decades ago, we have become more dependent on technology to assist us in evaluating a patient's fluid status and less skilled in basic physical examination and interpretation of common blood and urine values. Information obtained from these basic clinical skills is equally as, if not more, important as numbers derived by invasive means.  相似文献   
4.
A one year entomological survey was carried out to precise the malaria vectors and the malaria transmission in Yaounde, the Cameroon capital (800,000 inhabitants). The study was done in two districts not yet fully urbanized: Nkol Bikok and Nkol Bisson. The latter is located at the periphery and has a pool. Anopheles gambiae was the only human malaria vector. Its agressivity for man depended on the urbanization of the district. Annual man biting rate was 284 in Nkol Bikok and 1,813 in Nkol Bisson. The densities were maximum in May-June and in October-November, corresponding to the end of the short and long rainy seasons. The presence of A. gambiae was permanent except in August-September in Nkol Bikok. In Nkol Bisson the density was higher in the houses near the pool. The yearly inoculation rate (h) was 14 in Nkol Bikok and 30 in Nkol Bisson. The vectorial transmission was observed in may in Nkol Bikok and during four months (June, August, January, February) in Nkol Bisson. These entomological data showed clearly that malaria transmission actually occurred in Yaounde and that the probability to receive at least one infected anopheline bite per year was very near to 1 for inhabitants unprotected against mosquito bites.  相似文献   
5.
Sympathetic overactivity in patients with chronic renal failure.   总被引:23,自引:0,他引:23  
BACKGROUND: Hypertension is a frequent complication of chronic renal failure, but its causes are not fully understood. There is indirect evidence that increased activity of the sympathetic nervous system might contribute to hypertension in patients with end-stage renal disease, but sympathetic-nerve discharge has not been measured directly in patients or animals with chronic renal failure. METHODS: We recorded the rate of postganglionic sympathetic-nerve discharge to the blood vessels in skeletal muscle by means of microelectrodes inserted into the peroneal nerve in 18 patients with native kidneys who were undergoing long-term treatment with hemodialysis (of whom 14 had hypertension), 5 patients receiving hemodialysis who had undergone bilateral nephrectomy (of whom 1 had hypertension), and 11 normal subjects. RESULTS. The mean (+/- SE) rate of sympathetic-nerve discharge was 2.5 times higher in the patients receiving hemodialysis who had not undergone nephrectomy than in the normal subjects (58 +/- 3 vs. 23 +/- 3 bursts per minute, P < 0.01). In contrast, the rate of sympathetic-nerve discharge was similar in the patients receiving hemodialysis who had undergone bilateral nephrectomy (21 +/- 6 bursts per minute) and the normal subjects. The rate of sympathetic-nerve discharge in the patients receiving hemodialysis who had not undergone nephrectomy was also significantly higher (P < 0.01) than that in the patients with bilateral nephrectomy, and it was accompanied in the former group by higher values for vascular resistance in the calf (45 +/- 4 vs. 22 +/- 4 units, P < 0.05) and mean arterial pressure (106 +/- 4 vs. 76 +/- 14 mm Hg, P < 0.05). The rate of sympathetic-nerve discharge was not correlated with either plasma norepinephrine concentrations or plasma renin activity. CONCLUSIONS: Chronic renal failure may be accompanied by reversible sympathetic activation, which appears to be mediated by an afferent signal arising in the failing kidneys.  相似文献   
6.
BACKGROUND: This is a first attempt to evaluate the reliability and factor structure replicability of the Temperament Evaluation of Memphis, Pisa, Paris and San Diego Autoquestionnaire (TEMPS-A) in its Turkish Version. The questionnaire is a self-report 110-item measure that postulates five affective temperaments-the depressive, cyclothymic, irritable, hyperthymic, and anxious-which embody both strengths and liabilities along affective lines. METHODS: The questionnaire was administered to 658 clinically-well subjects in a Turkish university circle. We undertook item analysis and test-retest reliability. We then examined internal consistency through factor analysis with PCA rotation. RESULTS: We found good to excellent test-retest reliability (0.73-0.91), and internal consistency (0.77-0.85). We deleted 10 items with factor loading <0.20 for their own subscales, resulting in a questionnaire with 99 items. Despite considerable overlap between depressive and cognitive anxiety traits, a distinct "nervous"-anxious factor emerged as well, and the hypothesized (original English) 5-factor structure of the TEMPS-A was supported. Cut-offs for each temperament were based on z-scores higher than +2S.D. Dominant irritable (3.7%), nervous-anxious (3.7%) and depressive (3.1%) temperaments were the most common in this population, whereas dominant cyclothymic (1.7%) and hyperthymic (1.2%) temperaments were relatively uncommon. These temperaments tended to lose their intensity with age. As expected, women scored significantly higher on the nervous-anxious, and men on the hyperthymic temperaments. LIMITATIONS: The sample was composed of younger subjects with higher education than the general population of Turkey. Although the distribution of the scores for each of the temperaments deviated somewhat from normal curves, for heuristic reasons we did attempt to provide prevalence rates based on z-scores. CONCLUSION: In this preliminary version of the TEMPS-A, we have retained 100 (of the original 110) traits loading >0.20. Some deleted items referred to sleep, others appeared socially desirability traits in the Turkish culture endorsed by many subjects. Nonetheless, item analyses within each factor revealed traits indicative of personal assets (specific to each temperament) along with those which might represent vulnerability to affective illness. This is in line with the hypothesized original theoretical framework of the senior authors. Even in this "first pass," in its Turkish version the TEMPS-A is a reliable and valid instrument. Further refinement of the instrument will require the study of a nationally representative sample in Turkey.  相似文献   
7.
8.
9.
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