全文获取类型
收费全文 | 58424篇 |
免费 | 5469篇 |
国内免费 | 83篇 |
专业分类
耳鼻咽喉 | 980篇 |
儿科学 | 1571篇 |
妇产科学 | 1122篇 |
基础医学 | 7973篇 |
口腔科学 | 1681篇 |
临床医学 | 6900篇 |
内科学 | 11359篇 |
皮肤病学 | 817篇 |
神经病学 | 4906篇 |
特种医学 | 2167篇 |
外国民族医学 | 2篇 |
外科学 | 8290篇 |
综合类 | 1323篇 |
一般理论 | 50篇 |
预防医学 | 5820篇 |
眼科学 | 1429篇 |
药学 | 4203篇 |
1篇 | |
中国医学 | 41篇 |
肿瘤学 | 3341篇 |
出版年
2023年 | 363篇 |
2022年 | 590篇 |
2021年 | 1432篇 |
2020年 | 857篇 |
2019年 | 1373篇 |
2018年 | 1554篇 |
2017年 | 1033篇 |
2016年 | 1070篇 |
2015年 | 1242篇 |
2014年 | 1717篇 |
2013年 | 2616篇 |
2012年 | 3329篇 |
2011年 | 3331篇 |
2010年 | 1774篇 |
2009年 | 1599篇 |
2008年 | 2638篇 |
2007年 | 2749篇 |
2006年 | 2475篇 |
2005年 | 2416篇 |
2004年 | 2280篇 |
2003年 | 2017篇 |
2002年 | 1956篇 |
2001年 | 1454篇 |
2000年 | 1561篇 |
1999年 | 1400篇 |
1998年 | 524篇 |
1997年 | 429篇 |
1996年 | 462篇 |
1995年 | 421篇 |
1994年 | 413篇 |
1993年 | 414篇 |
1992年 | 1106篇 |
1991年 | 1049篇 |
1990年 | 1077篇 |
1989年 | 993篇 |
1988年 | 945篇 |
1987年 | 920篇 |
1986年 | 938篇 |
1985年 | 866篇 |
1984年 | 674篇 |
1983年 | 605篇 |
1982年 | 389篇 |
1981年 | 397篇 |
1980年 | 370篇 |
1979年 | 624篇 |
1978年 | 469篇 |
1977年 | 366篇 |
1974年 | 439篇 |
1973年 | 430篇 |
1971年 | 386篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
J. T. Lindsay Wilson 《Brain injury : [BI]》1990,4(4):349-363
Studies relating neuropsychology and structural neuroimaging after closed head injury are reviewed. Particular attention is given to the question of the relative contribution of focal and diffuse damage to neuropsychological impairment. The evidence currently available emphasizes the importance of diffuse damage in closed head injury. Diffuse damage is not equally distributed in the brain, and the review suggests three axes that are relevant for neuropsychological function: (1) damage may be unilateral or bilateral, (2) damage is characteristically greater in anterior regions than posterior regions, and (3) damage shows a centripetal gradient. A large gap remains between the emergent generalizations concerning head injury and reliable neuropsychological interpretation of scans from individual patients. 相似文献
52.
The chief medical residency in Canada: comparison of opinions between physicians-in-chief and chief medical residents. 下载免费PDF全文
We conducted a survey of physicians-in-chief (PCs) and chief medical residents (CMRs) in training programs throughout Canada to determine their attitudes toward the need for and role of CMRs in Canada and to rate the importance of CMR duties and attributes. Forty-three hospitals with 5 to 126 house staff in all eight provinces with medical schools were surveyed; 36 PCs (84%) and 29 CMRs (67%) returned a completed questionnaire. Compared with the CMRs the PCs preferred more prior training (p less than 0.03), estimated as significantly less the time spent by CMRs in required duties (p less than 0.05) and rated as more important the responsibilities of faculty-house staff liaison, house staff leader, house staff role model and teaching house staff (p less than 0.05) and the attributes of clinical judgement, medical knowledge, clinician model and research interests (p less than 0.03). All of the PCs and 97% of the CMRs rated the position as somewhat to very necessary; 83% of the PCs and 66% of the CMRs would not alter the present CMR roles. A total of 92% of the PCs felt that the position was very or somewhat advantageous with respect to a future private practice, compared with 67% of the CMRs (p less than 0.02). Increased administrative and committee duties, decreased teaching and future reductions in house staff were identified as major but reversible threats to the unique quality of the CMR position. We conclude that the CMR has a necessary, important and highly regarded role in Canadian university hospitals that could possibly be improved by regular review by the PC and CMR at each hospital to avoid the identified problems. 相似文献
53.
54.
S E Wilson W M Bourne P C O'Brien R F Brubaker 《American journal of ophthalmology》1988,106(3):270-278
Using a two-dimensional scanning fluorophotometer, we studied 50 subjects with symmetric ocular involvement of Fuchs' dystrophy without epithelial edema. Twenty-six subjects with confluent or nearly confluent cornea gutata with increased corneal thickness and 24 subjects with mild to moderate cornea guttata with normal corneal thickness were compared to normal control subjects. There were no statistically significant differences in endothelial permeability between the three groups. Corneal thickness was significantly increased in the subjects with confluent to nearly confluent guttae, however. These results suggest that endothelial pump function may be affected in subjects with advanced cornea guttata with stromal edema. 相似文献
55.
Andrew R. Hoellein MD Christopher A. Feddock MD Charles H. Griffith III MD MSPH John F. Wilson PhD Donald R. Barnett MD MSPH Pat F. Bass III MD MS T. Shawn Caudill MD MSPH 《Journal of general internal medicine》2004,19(5P2):562-565
Due to recent public debate and newly imposed resident work hour restrictions, we decided to investigate the relationship of resident call status to their ambulatory patients' satisfaction. Resident continuity clinic patients were asked to rate their level of satisfaction on a 10-point Likert-type scale. Using multiple regression approaches, these data were then assessed as a function of resident call status. We found that in 646 patient encounters, patient satisfaction scores were significantly less when the resident was postcall, 8.99 ± 1.8, than when not postcall, 9.31 ± 1.3. We herein discuss etiologies and implications of these findings for both patient care and medical education. 相似文献
56.
57.
58.
59.
12-month outcome of patients with major depression and comorbid psychiatric or medical illness (compound depression) 总被引:1,自引:0,他引:1
G I Keitner C E Ryan I W Miller R Kohn N B Epstein 《The American journal of psychiatry》1991,148(3):345-350
OBJECTIVE: Inpatients with major depressive illness often have coexistent nonaffective psychiatric and/or medical conditions. The authors' objective is to address the following questions: 1) What is the effect of comorbid illness on the severity of major depression and associated psychosocial factors? 2) How does the course of depression differ for patients with and without concurrent illness? 3) Do patients with compound depression differ in rate of recovery and time to recovery from patients with pure depression? METHOD: The subjects were 78 patients with a DSM-III diagnosis of major depression who were consecutively admitted to an acute care university-affiliated psychiatric hospital; 37 of these patients had major depression only and 41 had major depression compounded by a coexisting axis I, II, or III condition. The patients were studied while hospitalized and for 12 months after hospital discharge. Instruments used included the Modified Hamilton Rating Scale for Depression, the Global Assessment Scale, and the Social Readjustment Rating Scale. RESULTS: Patients with compound depression reported significantly poorer functioning over the 12-month follow-up period and had lower recovery rates than the patients with pure depression. There were no differences in recovery rates between men and women with compound depression, but significantly more men than women with pure depression recovered. CONCLUSIONS: Compound depression is a common clinical occurrence, the course of illness is more difficult for patients with compound depression than for patients with pure depression, and the recovery rate of patients with compound depression is lower than that of patients with pure depression. 相似文献
60.
Effect of indomethacin on arachidonic acid metabolism in human leukocytes stimulated ex vivo. 总被引:1,自引:0,他引:1
We had previously shown that inhibition of cyclooxygenase in vitro by indomethacin can cause increased formation of products of the 5-lipoxygenase pathway of arachidonic acid metabolism in leukocytes. To determine if this effect also occurred in vivo, we studied leukocyte arachidonic acid metabolism in 12 volunteers before and after ingestion of 150 mg indomethacin daily for 3 days. Blood was collected before treatment and 2 hours, 2 days, and 5 days after the final dose of indomethacin. Serum thromboxane B2, a measure of platelet cyclooxygenase activity, was profoundly suppressed 2 hours after the final dose of indomethacin but had recovered to control values at 2 days. Mixed leukocyte suspensions and purified neutrophil suspensions were prepared and stimulated with calcium ionophore A23187 and the resultant 5-lipoxygenase metabolites were quantified by HPLC. Two hours after the final dose of indomethacin, the stimulated levels of 5-hydroxyeicosatetraenoic acid, leukotriene B4, and leukotriene C4 were significantly increased to 247% +/- 68%, 135% +/- 14%, and 149% +/- 23% of pretreatment values, respectively. Two days after the final dose of indomethacin, 5-hydroxyeicosatetraenoic acid levels were still significantly elevated. By 5 days all parameters had returned to baseline. Similar effects were not observed in purified neutrophil suspensions, probably because of the loss of indomethacin from the cells during the multiple washing procedures used in their preparation. This is in accord with the reversible nature of the inhibitory effect of indomethacin on cyclooxygenase. We conclude that indomethacin at a commonly used dose increases the ability of circulating leukocytes to produce 5-lipoxygenase products. 相似文献