全文获取类型
收费全文 | 1620篇 |
免费 | 87篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 9篇 |
儿科学 | 111篇 |
妇产科学 | 105篇 |
基础医学 | 133篇 |
口腔科学 | 42篇 |
临床医学 | 169篇 |
内科学 | 326篇 |
皮肤病学 | 45篇 |
神经病学 | 61篇 |
特种医学 | 145篇 |
外科学 | 114篇 |
综合类 | 142篇 |
预防医学 | 106篇 |
眼科学 | 10篇 |
药学 | 91篇 |
1篇 | |
中国医学 | 74篇 |
肿瘤学 | 36篇 |
出版年
2021年 | 16篇 |
2020年 | 11篇 |
2018年 | 13篇 |
2017年 | 22篇 |
2016年 | 16篇 |
2015年 | 38篇 |
2014年 | 43篇 |
2013年 | 46篇 |
2012年 | 52篇 |
2011年 | 53篇 |
2010年 | 55篇 |
2009年 | 46篇 |
2008年 | 50篇 |
2007年 | 35篇 |
2006年 | 44篇 |
2005年 | 21篇 |
2004年 | 20篇 |
2003年 | 16篇 |
2002年 | 16篇 |
2001年 | 25篇 |
2000年 | 12篇 |
1999年 | 19篇 |
1998年 | 44篇 |
1997年 | 54篇 |
1996年 | 48篇 |
1995年 | 43篇 |
1994年 | 55篇 |
1993年 | 37篇 |
1992年 | 16篇 |
1991年 | 19篇 |
1990年 | 19篇 |
1989年 | 28篇 |
1988年 | 30篇 |
1987年 | 32篇 |
1986年 | 28篇 |
1985年 | 16篇 |
1984年 | 18篇 |
1983年 | 16篇 |
1982年 | 14篇 |
1981年 | 23篇 |
1980年 | 16篇 |
1959年 | 35篇 |
1958年 | 58篇 |
1957年 | 87篇 |
1956年 | 45篇 |
1955年 | 75篇 |
1954年 | 67篇 |
1953年 | 17篇 |
1952年 | 14篇 |
1949年 | 10篇 |
排序方式: 共有1720条查询结果,搜索用时 9 毫秒
91.
92.
93.
94.
Early pregnancy complications: endovaginal sonographic findings correlated with human chorionic gonadotropin levels 总被引:2,自引:0,他引:2
Endovaginal sonography results were compared with quantitatively determined human chorionic gonadotropin (hCG) levels in 84 women referred for early pregnancy complications. Of the 27 with normal intrauterine pregnancies, an intrauterine gestational sac was prospectively identified in one of five cases (20%) in which hCG levels were below 500 IU/L (Second International Standard), four of five (80%) with hCG levels of 500-1,000 IU/L, and all 17 with hCG levels above 1,000 IU/L. In comparison, 17 of the 26 women with ectopic pregnancies (65%) had hCG levels greater than 1,000 IU/L, and none of the 26 had an intrauterine gestational sac. Endovaginal sonography demonstrated an adnexal mass and/or a gestational sac-like structure in 16 of the 17 cases (94%) in which hCG levels were above 1,000 IU/L, compared with only three of the nine (33%) with lower hCG levels (P less than .01). These findings indicate that an intrauterine gestational sac should be normally visualized with endovaginal sonography when the hCG level exceeds 1,000 IU/L, and that visualization of an extrauterine gestational sac and/or adnexal mass is significantly more likely in ectopic pregnancies when the hCG level exceeds 1,000 IU/L. 相似文献
95.
EUGENE V. POMERANTSEV M.D. ANTONIO COLOMBO M.D. FACC LOUIS DE LA FUENTE M.D. EBERHARD GRUBE M.D. CRAIG JUERGENS M.D. D. MATHEY M.D. Ph.D. M. SCHALIJ M.D. J. J. GOY M.D. M.C. MORICE M.D. J. SCHOFER M.D. IRAWAN SUGENG M.D. FACC SIMON H. STERTZER M.D. FACC FOR THE AVE MICRO STENT STUDY GROUP 《Journal of interventional cardiology》1998,11(2):101-106
96.
97.
Thymic cysts in mediastinal Hodgkin disease 总被引:3,自引:0,他引:3
Three cases of proved thymic cysts associated with mediastinal Hodgkin disease are presented. Two illustrate regression of lymphoma with chemotherapy but persistence of thymic cysts. The third case demonstrates a thymic cyst in untreated Hodgkin disease. These cases suggest that such cysts are probably neither coincidental with nor a consequence of therapy but are probably related to initial thymic involvement by Hodgkin disease. 相似文献
98.
99.
Ronnie Z. Goetzel Lila G. Croen Sam Lan Robert E. Bases 《Pediatric blood & cancer》1982,10(4):413-418
As part of its evaluation of the Clinical Cancer Education Program (CCEP) at the Albert Einstein College of Medicine, the Office of Educational Research and Evaluation analyzed student performance on neoplastic items of the National Board of Medical Examiners (NBME) Examination Part II. The evaluation provided a successful application of the American Association for Cancer Education (AACE) coding schema for analysis of neoplastic items. Two examinations were analyzed in order to determine the frequency with which specific disease sites, treatment modalities, and question emphasis items appeared. With reference to disease site, the greatest number of questions on both examinations dealt with gynecological issues while the fewest dealt with lung and hematologic-related disease. A breakdown of questions into various treatment modalities indicated that of items that could be categorized, most dealt with surgical treatment, while other therapeutic modalities were given little or no emphasis. Looking at question emphases, the most frequently asked questions referred to diagnostic tests and stratagems, whereas the least amount of emphasis was placed on rehabilitative and psychosocial aspects of the disease. These findings corroborate those reported by Ruckdeschel and his associates and point out several limitations to the content validity of the neoplastic items on NBME Part II. 相似文献
100.