全文获取类型
收费全文 | 22585篇 |
免费 | 1919篇 |
国内免费 | 47篇 |
专业分类
耳鼻咽喉 | 228篇 |
儿科学 | 794篇 |
妇产科学 | 529篇 |
基础医学 | 2876篇 |
口腔科学 | 389篇 |
临床医学 | 2640篇 |
内科学 | 4455篇 |
皮肤病学 | 301篇 |
神经病学 | 1794篇 |
特种医学 | 991篇 |
外国民族医学 | 1篇 |
外科学 | 2867篇 |
综合类 | 533篇 |
一般理论 | 11篇 |
预防医学 | 2321篇 |
眼科学 | 859篇 |
药学 | 1511篇 |
1篇 | |
中国医学 | 25篇 |
肿瘤学 | 1425篇 |
出版年
2022年 | 144篇 |
2021年 | 384篇 |
2020年 | 217篇 |
2019年 | 384篇 |
2018年 | 450篇 |
2017年 | 337篇 |
2016年 | 356篇 |
2015年 | 444篇 |
2014年 | 591篇 |
2013年 | 822篇 |
2012年 | 1198篇 |
2011年 | 1226篇 |
2010年 | 691篇 |
2009年 | 683篇 |
2008年 | 1136篇 |
2007年 | 1198篇 |
2006年 | 1146篇 |
2005年 | 1060篇 |
2004年 | 1078篇 |
2003年 | 1012篇 |
2002年 | 974篇 |
2001年 | 556篇 |
2000年 | 579篇 |
1999年 | 516篇 |
1998年 | 265篇 |
1997年 | 255篇 |
1996年 | 227篇 |
1995年 | 242篇 |
1994年 | 226篇 |
1993年 | 211篇 |
1992年 | 403篇 |
1991年 | 426篇 |
1990年 | 394篇 |
1989年 | 397篇 |
1988年 | 348篇 |
1987年 | 333篇 |
1986年 | 335篇 |
1985年 | 322篇 |
1984年 | 249篇 |
1983年 | 200篇 |
1982年 | 158篇 |
1981年 | 141篇 |
1980年 | 144篇 |
1979年 | 183篇 |
1978年 | 145篇 |
1977年 | 147篇 |
1976年 | 121篇 |
1974年 | 134篇 |
1973年 | 139篇 |
1971年 | 118篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
31.
M Hunsberger A Mitchell S Blatz B Paes J Pinelli D Southwell S French R Soluk 《Clinical nurse specialist CNS》1992,6(2):91-96
We surveyed 655 health professionals affiliated with tertiary level neonatal intensive care units in Canada and the United States to define an expanded role for nurses in neonatology and to determine the educational requirements for the role. The role, comprising advanced clinical practice, educational, research, and administrative responsibilities, is a blend of nurse practitioner and clinical nurse specialist activities. Based on survey findings, a neonatal stream within the existing Master of Health Sciences program at McMaster University was developed. To date, 15 clinical nurse specialists/neonatal practitioners (CNS/NPs) are employed in five neonatal intensive care units in Ontario and other related institutions. A randomized trial to evaluate these individuals is in progress. 相似文献
32.
33.
From a population of singleton pregnancies, 152 overweight women (greater than 110% of standard) were matched with normal weight women (95-110%) for age, height, parity, race, and smoking habits. Comparisons were made of initial weight (weight at the first prenatal visit) and gestational weight gain and pregnancy outcome. Mean birth weights and gestational ages of infants of normal and overweight women were not significantly different. For normal weight women birth weight increased significantly as height, initial weight, and body mas index increased (p less than 0.01), but no such relationship existed for overweight women. The lack of effect of initial weight on birth weight in overweight women is attributable, in part, to the significantly less gestational weight gains of these mothers (6.3 kg vs 8.2 kg). When normal and overweight gravida had gestational weight gains of less than 7 kg, offspring of overweight mothers were significantly heavier. Gestational weight gain was positively correlated with birth weight for both normal (p less than 0.0001) and overweight women (p less than 0.001). Within the overweight and normal weight groups, smokers had lower initial weights and gestational weight gains than nonsmokers. Offspring of normal weight smokers had a mean birth weight 232 g less than that of nonsmokers (p less than 0.01). The difference in birth weight between overweight smokers and nonsmokers (135 g) was not statistically significant. While there is substantial data to support a weight gain of 10-12 kg in normal weight gravida, it would appear that a gain of approximately 7 kg in overweight middle class women does not impair fetal growth as measured by birth weight.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
34.
To investigate indirectly the central neurotransmitter mechanisms of D,L-fenfluramine-induced hormone release, prolactin, adrenocorticotropic hormone, cortisol, growth hormone, 3-methoxy-4-hydroxyphenylglycol (MHPG), homovanillic acid (HVA), and 5-hydroxyindoleacetic acid (5HIAA) responses to D,L-fenfluramine (60 mg, oral) were examined in a single-blind, placebo-controlled trial in 14 normal subjects. As compared with placebo, D,L-fenfluramine significantly increased both prolactin and cortisol. There was a significant correlation between the cortisol and prolactin responses. HVA levels were also significantly increased, but there were no changes in MHPG or 5HIAA. The elevation in HVA significantly correlated with increases in both prolactin and cortisol. These findings are consistent with recent animal studies suggesting that D,L-fenfluramine-induced prolactin and cortisol release may be mediated, at least in part, by catecholaminergic systems. 相似文献
35.
36.
One of the advantages of polyurethane foam-covered prostheses has been that in the first 5 to 10 years after their use, the
amount of capsular contraction was found much less than when similar ``slick' prostheses were used. Another advance was their
fixation to the surrounding tissue thus giving a more natural appearance and movement with the muscles when the arms were
moved in any direction. The formation of a thick capsule also acted as a protection against gel granuloma due to rupture of
the prosthesis and has been thought to be a factor in the lower capsule contraction rate. The greatest disadvantage has been
that its removal was extremely difficult and this has continued up until the technique described in this paper has been introduced. 相似文献
37.
Jonathan Cook Neil Prose Mitchell Heflin 《Dermatologic surgery》2003,29(9):1994; author reply 1994-1994; author reply 1995
38.
39.
40.
This study examined the potential beneficial effects of the addition of a second-generation sulfonylurea to insulin therapy for poorly controlled type II diabetes. A randomized, double-blind, crossover experimental design was utilized in 16 type II diabetic patients for a period of eight months. Treatment with glyburide, 20 mg/d (plus insulin), compared with placebo (plus insulin) resulted in a significant reduction in mean basal glucose (232 +/- 12 vs 262 +/- 11 mg/dL [12.8 vs 14.4 mmol/L]) and hemoglobin A1C (10.2% +/- 0.5% vs 10.9% +/- 03%) concentrations. Concomitant with this change, basal C-peptide and free insulin values increased with glyburide therapy, but this pharmacological agent did not alter the ability of the patient's erythrocytes to bind insulin. We conclude that in type II diabetic subjects receiving more than 28 units of insulin per day, the addition of glyburide results in a marginal, but statistically significant improvement in basal glucose concentration, but not in glucose tolerance as assessed by integrated glucose concentration. Whether this small improvement in glycemia is worth the additional cost of sulfonylureas or the risk of drug side effects is not known. 相似文献