全文获取类型
收费全文 | 346篇 |
免费 | 17篇 |
国内免费 | 52篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 10篇 |
基础医学 | 19篇 |
口腔科学 | 8篇 |
临床医学 | 57篇 |
内科学 | 70篇 |
皮肤病学 | 4篇 |
神经病学 | 2篇 |
特种医学 | 72篇 |
外科学 | 109篇 |
综合类 | 12篇 |
预防医学 | 9篇 |
眼科学 | 2篇 |
药学 | 27篇 |
肿瘤学 | 13篇 |
出版年
2021年 | 3篇 |
2019年 | 6篇 |
2018年 | 8篇 |
2017年 | 3篇 |
2016年 | 4篇 |
2015年 | 5篇 |
2014年 | 9篇 |
2013年 | 10篇 |
2012年 | 5篇 |
2011年 | 9篇 |
2010年 | 13篇 |
2009年 | 14篇 |
2008年 | 9篇 |
2007年 | 52篇 |
2006年 | 11篇 |
2005年 | 15篇 |
2004年 | 6篇 |
2003年 | 4篇 |
2002年 | 4篇 |
2001年 | 10篇 |
2000年 | 7篇 |
1999年 | 4篇 |
1998年 | 19篇 |
1997年 | 12篇 |
1996年 | 22篇 |
1995年 | 14篇 |
1994年 | 20篇 |
1993年 | 11篇 |
1992年 | 2篇 |
1991年 | 8篇 |
1990年 | 11篇 |
1989年 | 9篇 |
1988年 | 11篇 |
1987年 | 8篇 |
1986年 | 9篇 |
1985年 | 7篇 |
1984年 | 3篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1981年 | 4篇 |
1980年 | 6篇 |
1979年 | 1篇 |
1978年 | 3篇 |
1977年 | 6篇 |
1976年 | 5篇 |
1975年 | 4篇 |
1973年 | 1篇 |
1971年 | 1篇 |
1962年 | 1篇 |
1959年 | 1篇 |
排序方式: 共有415条查询结果,搜索用时 15 毫秒
41.
42.
Invasion of erythrocytes by Plasmodium falciparum malaria parasites: evidence for receptor heterogeneity and two receptors 总被引:19,自引:0,他引:19
Plasmodium falciparum malaria parasites with different capabilities of invading sialic acid-deficient erythrocytes were identified. Thai-2 parasites cultured in Tn erythrocytes invaded neuraminidase-treated and Tn erythrocytes twice as efficiently as Thai-2 parasites cultured in normal erythrocytes and seven to ten times more efficiently than a cloned line of Camp parasites cultured in normal erythrocytes. All three parasite lines required sialic acid for optimal invasion, but Thai-2 parasites cultured in Tn erythrocytes invaded neuraminidase- treated erythrocytes with 45% efficiency whereas Camp parasites invaded neuraminidase-treated erythrocytes with less than 10% efficiency. P falciparum malaria parasites probably possess two receptors: one that binds to a sialic acid-dependent ligand and another that binds to a sialic acid-independent ligand. Parasites may differ in the quantity or affinity of their receptors for the sialic acid-independent ligand. 相似文献
43.
44.
Correlation of P-glycoprotein expression and function in childhood acute leukemia: a children's cancer group study 总被引:7,自引:0,他引:7
Clinical drug resistance may be attributed to the simultaneous selection and expression of genes modulating the uptake and metabolism of chemotherapeutic agents. P-glycoprotein (P-gp) functions as a membrane-associated drug efflux pump whose increased expression results in resistance to anthracyclines, epipodophyllotoxins, vinca alkaloids, and some alkylating agents. This type of resistance occurs as both de novo and acquired resistance to therapy for leukemia. We have studied P- gp expression and function in childhood acute leukemias by developing a series of doxorubicin- and vincristine-selected CEM, T-cell lymphoblastoid cell lines that recapitulate the low levels of expression and resistance seen clinically. These cell lines have been used to develop flow cytometric assays for the semiquantitative measurements of P-gp expression with the MRK16 monoclonal antibody and P-gp function using the enhanced retention of rhodamine 123 in the presence of verapamil, a resistance modulator. Kolmogorov-Smirnov statistics, represented by the D measurement, are used to determine the difference in level of P-gp expression by comparing MRK16 staining to an IgG2a isotype control. When D is > 0.09, there is an excellent correlation (R = 0.82) between P-gp expression and function. The evaluation of 107 bone marrow specimens from 84 children with lymphoblastic or myelogenous leukemia showed a statistically significant (P = .004) increase in P-gp function at relapse. P-gp expression at relapse, however, approached but did not reach a significant level (P = .097). Using this methodology, we can identify patients with levels of P-gp expression and function that we can define clinically, as well as children with discordant multidrug resistance phenotypes. This study supports the role of P-gp-mediated drug resistance in childhood leukemia and confirms that P-gp expression and function are measurable in their leukemic blasts. These assays provide the means for the in vitro testing of resistance modulators and the monitoring of in vivo response to treatment with these agents. 相似文献
45.
Teerenhovi L; Knuutila S; Ekblom M; Rossi L; Borgstrom GH; Tallman JK; Andersson L; de la Chapelle A 《Blood》1984,64(5):1116-1122
A major problem in the cytogenetic analysis of hematologic neoplasms has been an inability to identify the cell from which the chromosomes were obtained. We describe a procedure that allows simultaneous analysis of karyotype and cell cytology in mitotic cells. The method differs from conventional cytogenetic analysis in that after mild hypotonic treatment, the cells are cytocentrifuged onto glass slides. In mitotic cells, this procedure often results in adequate spread of the chromosomes within the intact cell membrane. The cytoplasmic structure also remains intact, so that cytologic preparations are of good quality. Morphologic and immunologic identification of mitotic cells can be done using routine hematologic stains, such as Giemsa or Sudan black B, and various antisera using immunofluorescence techniques. The chromosomes can be simultaneously analyzed either without banding on slides stained with Giemsa or with Q-banding on slides stained with immunofluorescence techniques. Identification of numerical and structural karyotype aberrations thus is possible in morphologically identified cells. 相似文献
46.
Abel N Kho Denise M Hynes Satyender Goel Anthony E Solomonides Ron Price Bala Hota Shannon A Sims Neil Bahroos Francisco Angulo William E Trick Elizabeth Tarlov Fred D Rachman Andrew Hamilton Erin O Kaleba Sameer Badlani Samuel L Volchenboum Jonathan C Silverstein Jonathan N Tobin Michael A Schwartz David Levine John B Wong Richard H Kennedy Jerry A Krishnan David O Meltzer John M Collins Terry Mazany for the CAPriCORN Team 《J Am Med Inform Assoc》2014,21(4):607-611
The Chicago Area Patient-Centered Outcomes Research Network (CAPriCORN) represents an unprecedented collaboration across diverse healthcare institutions including private, county, and state hospitals and health systems, a consortium of Federally Qualified Health Centers, and two Department of Veterans Affairs hospitals. CAPriCORN builds on the strengths of our institutions to develop a cross-cutting infrastructure for sustainable and patient-centered comparative effectiveness research in Chicago. Unique aspects include collaboration with the University HealthSystem Consortium to aggregate data across sites, a centralized communication center to integrate patient recruitment with the data infrastructure, and a centralized institutional review board to ensure a strong and efficient human subject protection program. With coordination by the Chicago Community Trust and the Illinois Medical District Commission, CAPriCORN will model how healthcare institutions can overcome barriers of data integration, marketplace competition, and care fragmentation to develop, test, and implement strategies to improve care for diverse populations and reduce health disparities. 相似文献
47.
48.
49.
50.