全文获取类型
收费全文 | 42955篇 |
免费 | 3009篇 |
国内免费 | 148篇 |
专业分类
耳鼻咽喉 | 464篇 |
儿科学 | 1377篇 |
妇产科学 | 1175篇 |
基础医学 | 5914篇 |
口腔科学 | 493篇 |
临床医学 | 6269篇 |
内科学 | 8233篇 |
皮肤病学 | 712篇 |
神经病学 | 4352篇 |
特种医学 | 810篇 |
外国民族医学 | 1篇 |
外科学 | 3453篇 |
综合类 | 763篇 |
一般理论 | 42篇 |
预防医学 | 5008篇 |
眼科学 | 884篇 |
药学 | 2980篇 |
中国医学 | 79篇 |
肿瘤学 | 3103篇 |
出版年
2023年 | 223篇 |
2022年 | 469篇 |
2021年 | 863篇 |
2020年 | 478篇 |
2019年 | 799篇 |
2018年 | 931篇 |
2017年 | 721篇 |
2016年 | 803篇 |
2015年 | 974篇 |
2014年 | 1308篇 |
2013年 | 1989篇 |
2012年 | 3010篇 |
2011年 | 3166篇 |
2010年 | 1603篇 |
2009年 | 1556篇 |
2008年 | 2843篇 |
2007年 | 3064篇 |
2006年 | 3144篇 |
2005年 | 3092篇 |
2004年 | 3008篇 |
2003年 | 2824篇 |
2002年 | 2614篇 |
2001年 | 371篇 |
2000年 | 269篇 |
1999年 | 371篇 |
1998年 | 483篇 |
1997年 | 417篇 |
1996年 | 378篇 |
1995年 | 361篇 |
1994年 | 267篇 |
1993年 | 297篇 |
1992年 | 206篇 |
1991年 | 205篇 |
1990年 | 185篇 |
1989年 | 179篇 |
1988年 | 191篇 |
1987年 | 152篇 |
1986年 | 131篇 |
1985年 | 150篇 |
1984年 | 190篇 |
1983年 | 185篇 |
1982年 | 237篇 |
1981年 | 176篇 |
1980年 | 184篇 |
1979年 | 110篇 |
1978年 | 107篇 |
1977年 | 112篇 |
1976年 | 86篇 |
1975年 | 71篇 |
1974年 | 78篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
Barbara Sibbald 《Canadian Medical Association journal》2005,172(9):1169
12.
Nicola Martinelli Domenico Girelli Paolo Ferraresi Oliviero Olivieri Barbara Lunghi Franco Manzato Roberto Corrocher Francesco Bernardi 《Blood coagulation & fibrinolysis》2007,18(2):125-129
A common factor V gene haplotype, the FVR2 haplotype (FVHR2), has been associated with a reduced cofactor activity in activated protein C-mediated activated factor VIII inactivation. Our aim was to investigate the role of FVHR2 as a possible determinant of factor VIII levels in a population study. A total of 516 individuals (401 men, 115 women; mean age 58.4 +/- 10.8 years) were enrolled within the frame of a regional cardiovascular survey, characterized for factor VIII coagulant activity (FVIII:c) and factor V coagulant activity (FV:c) levels, and genotyped for factor V polymorphisms. In men without signs of overt inflammation, FVHR2 carriers had higher levels of FVIII:c than noncarriers (154 IU/dl, 95% confidence interval = 143-166 versus 142 IU/dl, 95% confidence interval = 138-147; P = 0.045) and were more represented in individuals with high (> or = 150 IU/dl) FVIII:c levels (21.2 versus 10.8%; odds ratio = 2.27, 95% confidence interval = 1.17-4.39 after adjustment for age, blood group and high-sensitivity C-reactive protein levels). In conclusion, this clinical report suggests the common FVHR2 as a possible independent determinant of FVIII:c levels. The report concomitantly addresses the relationship between factor V and factor VIII levels and supports the hypothesis of a mild prothrombotic role of FVHR2 by means of increased factor VIII levels. 相似文献
13.
Factors affecting aseptic loosening of 4750 total hip arthroplasties: multivariate survival analysis
Barbara Bordini Susanna Stea Manuela De Clerico Sergio Strazzari Antonio Sasdelli Aldo Toni 《BMC musculoskeletal disorders》2007,8(1):69
Background
Total hip arthroplasty is a successful surgery, that fails at a rate of approximately 10% at ten years from surgery. Causes for failure are mainly aseptic loosening of one or both components partially due to wear of articular surfaces and partially to design. The present analysis aimed to identify risk factors and quantify their effects on aseptic failure. 相似文献14.
15.
Barbara Sibbald 《Canadian Medical Association journal》2004,170(8):1218-1219
16.
17.
18.
M Joan Taylor Sangeeta Tanna Tarsem S Sahota Barbara Voermans 《European journal of pharmaceutics and biopharmaceutics》2006,62(1):94-100
The rheological characterisation of glucose sensitive mixtures containing dextran and concanavalin A (con A) with and without glucose, was undertaken using oscillatory rheometry at 20 and 37 degrees C so that comparative data could be gathered in the linear viscoelastic (LVE) range. Measurements for a series of mixtures showed that complex viscosity is a function not only of the con A concentration but of the content and molecular weight of the dextran used. The extent of liquefaction on addition of glucose also depended on these factors. The tan delta profiles confirmed the change from semi-solid towards fluid behaviour. This occurs when glucose effects dismantling of the three-dimensional structure of the dextran-con A system by competitive binding to the glucose receptors in the protein. For the mixtures studied, the changes occurred between contents of 0 and 1% (w/w) glucose at 20 and 37 degrees C and form a useful basis for the formulation of a self-regulating delivery device for the control of hyper-and hypoglycaemia in diabetes. 相似文献
19.
ABSTRACT: Background: Most women will sustain some degree of trauma to the genital tract after vaginal birth. This study aimed to examine the association between maternal position at birth and perineal outcome in women who had a midwife‐attended, spontaneous vaginal birth and an uncomplicated pregnancy at term. Methods: Data from 3,756 births in a major public tertiary teaching hospital were eligible for analysis. The need for sutures in perineal trauma was evaluated and compared for each major factor studied (maternal age, first vaginal delivery, induction of labor, not occipitoanterior, use of regional anesthesia, deflexed head and newborn birthweight >3,500 g). Birth positions were compared against each other. Subgroup analysis determined whether birth positions mattered more or less in each of the major factors studied. The chi‐square test was used to compare categorical variables. Results: Most women (65.9%) gave birth in the semi‐recumbent position. Of the 1,679 women (44.5%) who required perineal suturing, semi‐recumbent position was associated with the need for perineal sutures, whereas all‐fours was associated with reduced need for sutures; these associations were more marked in first vaginal births and newborn birth weight over 3,500 g. When regional anesthesia was used, semi‐recumbent position was associated with a need for suturing, and lateral position associated with a reduced need for suturing. The four major factors significantly related to perineal trauma included first vaginal birth, use of regional anesthesia, deflexed head, and newborn weight more than 3,500 g. Conclusions: Women should be given the choice to give birth in whatever position they find comfortable. Maternity practitioners have a responsibility to inform women of the likelihood of perineal trauma in the preferred birth position. Ongoing audit of all clinicians attending births is encouraged to further determine effects of maternal birth position and perineal trauma, to investigate women's perception of comfortable positioning at birth, and to measure changes to midwifery practice resulting from this study. 相似文献
20.