全文获取类型
收费全文 | 1333493篇 |
免费 | 101950篇 |
国内免费 | 4263篇 |
专业分类
耳鼻咽喉 | 16799篇 |
儿科学 | 43584篇 |
妇产科学 | 36365篇 |
基础医学 | 197830篇 |
口腔科学 | 35913篇 |
临床医学 | 129558篇 |
内科学 | 258076篇 |
皮肤病学 | 26377篇 |
神经病学 | 111861篇 |
特种医学 | 48170篇 |
外国民族医学 | 366篇 |
外科学 | 184028篇 |
综合类 | 28772篇 |
现状与发展 | 1篇 |
一般理论 | 460篇 |
预防医学 | 114364篇 |
眼科学 | 28985篇 |
药学 | 98831篇 |
6篇 | |
中国医学 | 3166篇 |
肿瘤学 | 76194篇 |
出版年
2021年 | 10902篇 |
2019年 | 11631篇 |
2018年 | 16324篇 |
2017年 | 12289篇 |
2016年 | 13250篇 |
2015年 | 15196篇 |
2014年 | 20799篇 |
2013年 | 32056篇 |
2012年 | 44239篇 |
2011年 | 46892篇 |
2010年 | 27075篇 |
2009年 | 24923篇 |
2008年 | 42718篇 |
2007年 | 45055篇 |
2006年 | 45168篇 |
2005年 | 43589篇 |
2004年 | 41560篇 |
2003年 | 39497篇 |
2002年 | 38304篇 |
2001年 | 60844篇 |
2000年 | 62513篇 |
1999年 | 52275篇 |
1998年 | 14578篇 |
1997年 | 13274篇 |
1996年 | 13114篇 |
1995年 | 12456篇 |
1994年 | 11625篇 |
1993年 | 10920篇 |
1992年 | 41568篇 |
1991年 | 40761篇 |
1990年 | 39445篇 |
1989年 | 37342篇 |
1988年 | 34582篇 |
1987年 | 33693篇 |
1986年 | 32151篇 |
1985年 | 30638篇 |
1984年 | 23034篇 |
1983年 | 19590篇 |
1982年 | 11752篇 |
1979年 | 20804篇 |
1978年 | 14816篇 |
1977年 | 12064篇 |
1976年 | 11876篇 |
1975年 | 12110篇 |
1974年 | 14800篇 |
1973年 | 14472篇 |
1972年 | 13356篇 |
1971年 | 12418篇 |
1970年 | 11489篇 |
1969年 | 10411篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Gamma-glutamyl transpeptidase (GGT) activity has been demonstratedhistochemically in a number of experimentally induced neoplasmsand has been suggested as a label for potential precursors forthe development of squamous cell carcinomas. This study exploresthe kinetics of GGT-stained cell populations, their correlationwith the hypothesized initiated cells and evidence of malignanttransformation of epithelium in hamster buccal pouch by a 15-weekregime of tri-weekly topical application of 7,12-dimethylbenz[a]anthracene(DMBA) in mineral oil. GGT-positive foci were detected histochemicallyin tissue sections as early as 1 week after application of thecarcinogen, when there was no morphological evidence of dysplasia.The average number of the GGT-positive foci in each experimentalperiod was found to increase with time. Even though the majorityof the foci were small, consisting of only a single cell ora small group of cells, a few larger GGT-positive lesions werenoted, particularly in the later period of the experiment. Atotal of 66 grossly visible neoplasms were found. Thirty-sevenof these were submitted for GGT staining. Thirty-two (86.5%)of these showed patchy GGT activity, primarily in the superficialepithelial cells and/or the keratin. In the non-neoplastic epithelium,the GGT staining could involve any or all layers of cells. GGTactivity was not detected in untreated or mineral oil-treatedmucosa. The results of this study support the hypothesis thatGGT activity may label potential precursors for the developmentof squamous cell carcinomas. 相似文献
992.
J L Schrader 《The American journal of psychiatry》1987,144(1):107-109
The Alaska mental health program is endowed with a 1-million-acre trust fund. A coalition of groups that make up the mental health constituency of the state united in a lawsuit to establish the trust. The history of this legacy, the struggle to realize its benefits, its current status, and some of its psychopolitical significance are discussed. 相似文献
993.
994.
995.
996.
997.
F. Lesoin M. Rousseaux N. Bouasakao L. Villette C. E. Thomas A. Cama M. Jomin 《Acta neurochirurgica》1986,81(3-4):118-124
Summary The authors report 165 cases of thoraco-lumbar lesions with neurological dysfunction. All the patient were operated. They analyze the neurological and mechanical results and indicate the use of different osteosynthesis apparatus according to the type and level of lesions.Harrington's rods seem to give more precise repositioning while Roy Camille's plates give more stability. When the posterior wall of the spinal canal is intact, Kempf's compression rods can be used.Thoraxic spine injuries seem to be an indication for Harrington's rods, while lumbar injuries seem to call for Camille's plates. 相似文献
998.
Intrathecal morphine for post-thoracotomy pain 总被引:1,自引:0,他引:1
We wished to investigate possible differences in the duration of postoperative analgesia and the incidence of respiratory depression after the intrathecal injection in the lumbar area of 10 micrograms/kg morphine in hypobaric and hyperbaric solution for relief of post-thoracotomy pain. Twenty-nine patients received morphine plus dextrose (hyperbaric) and 21 received morphine in preservative-free normal saline. The duration of analgesia was longer with the morphine in the normal saline group than in the hyperbaric group (P less than 0.04). One patient developed delayed respiratory depression. Our data support the use of morphine in normal saline mixtures for greater duration of analgesia after thoracic operations. 相似文献
999.
1000.
Do-not-resuscitate orders for critically ill patients in the hospital. How are they used and what is their impact? 总被引:9,自引:0,他引:9
We studied compliance with do-not-resuscitate (DNR) orders at a university hospital where a DNR protocol has existed since 1979. Documentation of DNR status in patient progress notes and chart orders increased through 1983. During a 12-month period (March 1983 through April 1984), we studied in detail the medical records of 521 patients who had a cardiopulmonary arrest in the hospital. Seventy-five percent (389 of 521) of these patients were designated DNR. Patients who were designated DNR were significantly more likely to be older, to have malignancy or an abnormal mental status, and to be less likely to have acute myocardial infarction, stroke, or chronic obstructive pulmonary disease than patients in whom resuscitation was attempted. Eighty-six percent of families, but only 22% of patients, were involved in the decision to designate a patient DNR. The decision to designate a patient DNR occurred late in the course of a patient's illness, often when the patient was in coma. For 28% of patients, some form of medical care was withdrawn or withheld after they were designated DNR. These data suggest that use of the DNR protocol requires changes if patients are to participate in the decision not to undergo cardiopulmonary resuscitation. 相似文献