全文获取类型
收费全文 | 741篇 |
免费 | 43篇 |
国内免费 | 20篇 |
专业分类
耳鼻咽喉 | 2篇 |
儿科学 | 29篇 |
妇产科学 | 8篇 |
基础医学 | 52篇 |
口腔科学 | 33篇 |
临床医学 | 148篇 |
内科学 | 155篇 |
皮肤病学 | 3篇 |
神经病学 | 9篇 |
特种医学 | 159篇 |
外科学 | 38篇 |
综合类 | 48篇 |
预防医学 | 38篇 |
药学 | 30篇 |
中国医学 | 17篇 |
肿瘤学 | 35篇 |
出版年
2023年 | 6篇 |
2022年 | 4篇 |
2021年 | 14篇 |
2020年 | 3篇 |
2019年 | 5篇 |
2018年 | 9篇 |
2017年 | 7篇 |
2016年 | 10篇 |
2015年 | 7篇 |
2014年 | 15篇 |
2013年 | 25篇 |
2012年 | 17篇 |
2011年 | 20篇 |
2010年 | 26篇 |
2009年 | 45篇 |
2008年 | 19篇 |
2007年 | 25篇 |
2006年 | 11篇 |
2005年 | 20篇 |
2004年 | 12篇 |
2003年 | 13篇 |
2002年 | 15篇 |
2001年 | 16篇 |
2000年 | 19篇 |
1999年 | 10篇 |
1998年 | 41篇 |
1997年 | 38篇 |
1996年 | 37篇 |
1995年 | 35篇 |
1994年 | 22篇 |
1993年 | 26篇 |
1992年 | 13篇 |
1991年 | 10篇 |
1990年 | 10篇 |
1989年 | 27篇 |
1988年 | 25篇 |
1987年 | 15篇 |
1986年 | 11篇 |
1985年 | 18篇 |
1984年 | 10篇 |
1983年 | 8篇 |
1982年 | 19篇 |
1981年 | 12篇 |
1980年 | 17篇 |
1978年 | 8篇 |
1977年 | 12篇 |
1976年 | 8篇 |
1975年 | 3篇 |
1974年 | 2篇 |
1969年 | 1篇 |
排序方式: 共有804条查询结果,搜索用时 0 毫秒
71.
72.
73.
A clinical study comparing digital radiography and near‐infrared transillumination in caries detection 下载免费PDF全文
74.
Razee H Whittaker M Jayasuriya R Yap L Brentnall L 《Social science & medicine (1982)》2012,75(5):828-835
Despite rural health services being situated and integrated within communities in which people work and live, the complex interaction of the social environment on health worker motivation and performance in Low Middle Income Countries has been neglected in research. In this article we investigate how social factors impact on health worker motivation and performance in rural health services in Papua New Guinea (PNG). Face-to-face in-depth interviews were conducted with 33 health workers from three provinces (Central, Madang, and Milne Bay) in PNG between August and November 2009. They included health extension officers, community health workers and nursing officers, some of whom were in charge of the health centres. The health centres were a selection across church based, government and private enterprise health facilities. Qualitative analysis identified the key social factors impacting on health worker motivation and performance to be the local community context, gender roles and family related issues, safety and security and health beliefs and attitudes of patients and community members. Our study identified the importance of strong supportive communities on health worker motivation. These findings have implications for developing sustainable strategies for motivation and performance enhancement of rural health workers in resource poor settings. 相似文献
75.
76.
Human acute leukemia cell line with the t(4;11) chromosomal rearrangement exhibits B lineage and monocytic characteristics 总被引:18,自引:8,他引:18
A cell line, designated RS4;11, was established from the bone marrow of a patient in relapse with an acute leukemia that was characterized by the t(4;11) chromosomal abnormality. The cell line and the patient's fresh leukemic cells both had the t(4;11)(q21;q23) and an isochromosome for the long arm of No. 7. Morphologically, all cells were lymphoid in appearance. Ultrastructurally and cytochemically, approximately 30% of the cells possessed myeloid features. The cells were strongly positive for terminal deoxynucleotidyl transferase. They were HLA-DR positive and expressed surface antigens characteristic for B lineage cells, including those detected by anti-B4, BA-1, BA-2, and PI153/3. Immunoglobulin gene analysis revealed rearrangements of the heavy chain and kappa chain genes. The cells lacked the common acute lymphoblastic leukemia antigen and antigenic markers characteristic of T lineage cells. The cells reacted with the myeloid antibody 1G10 but not with other myeloid monoclonal antibodies. Treatment with 12-O-tetradecanoyl- phorbol-13-acetate induced a monocyte-like phenotype demonstrated by cytochemical, functional, immunologic, and electron microscopic studies. The expression of markers of both early lymphoid and early myeloid cells represents an unusual phenotype and suggests that RS4;11 represents a cell with dual lineage capabilities. To our knowledge, RS4;11 is the first cell line established from t(4;11)-associated acute leukemia. 相似文献
77.
78.
79.
Transient leukemoid proliferation of the cytogenetically unbalanced +21 cell line of a constitutional mosaic boy 总被引:1,自引:0,他引:1
A newborn without any signs of Down's syndrome was found to have an acute proliferation that remitted without drug therapy. Chromosomal analysis of blood, bone marrow, and skin cells revealed that the child was a constitutional mosaic with normal cells and a low number of cells in which one no. 21 chromosome was replaced by a probably isochromosome for the no. 21 long arm: 46,XY/46,XY,i(21q). The abnormal cell line of the mosaic appeared to be selectively involved in this proliferation. 相似文献
80.
Allogeneic marrow transplantation for refractory anemia: a comparison of two preparative regimens and analysis of prognostic factors 总被引:3,自引:3,他引:3
Anderson JE; Appelbaum FR; Schoch G; Gooley T; Anasetti C; Bensinger WI; Bryant E; Buckner CD; Chauncey TR; Clift RA; Doney K; Flowers M; Hansen JA; Martin PJ; Matthews DC; Sanders JE; Shulman H; Sullivan KM; Witherspoon RP; Storb R 《Blood》1996,87(1):51-58
From 1990 to 1993 we performed a prospective study of busulfan (16 mg/kg) and cyclophosphamide (120 mg/kg) in 30 patients with refractory anemia (RA) undergoing related (n = 17) or unrelated (n = 13) donor marrow transplantation. Nineteen patients survive disease free (63% 3- year actuarial disease-free survival [DFS]) and no patient relapsed. These results were compared to those of 38 historical controls with RA treated with cyclophosphamide and total body irradiation, of whom 22 are disease-free survivors and 1 relapsed. After correcting for significant variables between the two treatment groups, we found no statistically significant difference in outcome based on preparative regimen. Combining data from these 68 patients plus 2 additional patients with RA treated before 1993 with busulfan and cyclophosphamide, we identified four variables independently associated with improved survival: younger age, shorter disease duration, lower neutrophil count pretransplant, and lower hematocrit pretransplant. We also found that 15 patients 40 to 55 years of age had a 46% 3-year actuarial DFS and 26 patients receiving unrelated or mismatched related donor marrow had a 50% 3-year actuarial DFS. We conclude that there does not appear to be any significant difference in outcome based on preparative regimen in this patient population. In addition, allogeneic bone marrow transplantation may be a reasonable approach to therapy of RA early after diagnosis. However, whether early intervention with transplantation prolongs survival over that expected without transplantation cannot be ascertained with certainty from available data. 相似文献