全文获取类型
收费全文 | 1869篇 |
免费 | 101篇 |
国内免费 | 3篇 |
专业分类
耳鼻咽喉 | 12篇 |
儿科学 | 55篇 |
妇产科学 | 39篇 |
基础医学 | 263篇 |
口腔科学 | 28篇 |
临床医学 | 221篇 |
内科学 | 313篇 |
皮肤病学 | 18篇 |
神经病学 | 113篇 |
特种医学 | 105篇 |
外科学 | 229篇 |
综合类 | 17篇 |
一般理论 | 1篇 |
预防医学 | 135篇 |
眼科学 | 77篇 |
药学 | 142篇 |
中国医学 | 9篇 |
肿瘤学 | 196篇 |
出版年
2023年 | 21篇 |
2022年 | 48篇 |
2021年 | 88篇 |
2020年 | 46篇 |
2019年 | 51篇 |
2018年 | 65篇 |
2017年 | 49篇 |
2016年 | 42篇 |
2015年 | 49篇 |
2014年 | 70篇 |
2013年 | 104篇 |
2012年 | 136篇 |
2011年 | 121篇 |
2010年 | 70篇 |
2009年 | 69篇 |
2008年 | 86篇 |
2007年 | 107篇 |
2006年 | 94篇 |
2005年 | 87篇 |
2004年 | 73篇 |
2003年 | 79篇 |
2002年 | 57篇 |
2001年 | 52篇 |
2000年 | 38篇 |
1999年 | 49篇 |
1998年 | 18篇 |
1997年 | 16篇 |
1996年 | 10篇 |
1995年 | 9篇 |
1994年 | 11篇 |
1993年 | 3篇 |
1992年 | 24篇 |
1991年 | 18篇 |
1990年 | 12篇 |
1989年 | 16篇 |
1988年 | 17篇 |
1987年 | 12篇 |
1986年 | 14篇 |
1985年 | 2篇 |
1984年 | 6篇 |
1983年 | 9篇 |
1982年 | 3篇 |
1981年 | 2篇 |
1980年 | 3篇 |
1974年 | 4篇 |
1973年 | 2篇 |
1971年 | 2篇 |
1969年 | 1篇 |
1968年 | 2篇 |
1967年 | 1篇 |
排序方式: 共有1973条查询结果,搜索用时 0 毫秒
1.
J C Mason K S Ordelheide G M Grames T V Thrasher R D Harris R H Bui M C Mackett 《Transplantation》1987,44(4):588-591
2.
High-dose methotrexate (MTX) toxicity is reduced by a non-toxic dose of 5-fluorouracil (FU) when these agents are used in combination. Changes in the hematopoietic system (platelets, erythrocytes, leukocytes, hemoglobin, and hematocrit), ileal tissue, body weight, and mean survival were used as parameters to assess toxicity. For all parameters studied, there were no significant differences between the scheduling of MTX (245 mg/kg) after a priming dose of FU (25 mg/kg), simultaneous MTX and FU, FU alone, and control. However, sequential treatment with MTX followed by FU, and MTX alone resulted in: a marked decrease in the hematopoietic parameters; significant morphological changes in ileal tissue; a reduction of body weight; and increased mortality of animals. Hence, this study suggests that FU, a cytotoxic agent, may protect against MTX toxicity and improve its therapeutic index when FU administration precedes MTX or when these agents are given simultaneously. 相似文献
3.
Phacolytic glaucoma (PG) is usually caused by hypermature lens and the principal mechanism is the obstructed trabecular mesh-work with the leaky lens capsule proteins The incidence of PG in author’s hospital, where the backlog of cataract is relatively high, occupied ten percent of operated glaucoma and three percent of cataract surgeries. The PG in severe cases is commonly misdiagnosed with endophthalmitis and was therefore 相似文献
4.
Isabelle Knott Marc Dieu Maggi Burton Véronique Lecomte José Remacle Martine Raes 《Inflammation research》1993,39(3-4):126-131
The effects of interleukin-1 and were tested on the [3H]-arachidonic acid release and the prostaglandin synthesis by human cultured synovial cells and chondrocytes. Both forms of interleukin-1 stimulated the arachidonic acid release but interleukin-1 was more potent than IL-1. Human synovial cells and chondrocytes synthesized three types of prostaglandins upon stimulation with interleukin-1 or : prostaglandin E2, F2 and 6-keto-prostaglandin F1. Regarding the synthesis of these prostaglandins, IL-1 was again more potent than IL-1. A comparison between interleukin-1-stimulated synovial cells and chondrocytes revealed neither significant quantitative nor qualitative differences in both the arachidonic acid release and the prostaglandin synthesis. 相似文献
5.
Yang JQ Chun T Liu H Hong S Bui H Van Kaer L Wang CR Singh RR 《European journal of immunology》2004,34(6):1723-1732
Mechanisms responsible for the development of autoimmune skin disease in humans and animal models with lupus remain poorly understood. In this study, we have investigated the role of CD1d, an antigen-presenting molecule known to activate natural killer T cells, in the development of inflammatory dermatitis in lupus-susceptible MRL-lpr/lpr mice. In particular, we have established MRL-lpr/lpr mice carrying a germ-line deletion of the CD1d genes. We demonstrate that CD1d-deficient MRL-lpr/lpr mice, as compared with wild-type littermates, have more frequent and more severe skin disease, with increased local infiltration with mast cells, lymphocytes and dendritic cells, including Langerhans cells. CD1d-deficient MRL-lpr/lpr mice had increased prevalence of CD4(+) T cells in the spleen and liver and of TCR alpha beta (+)B220(+) cells in lymph nodes. Furthermore, CD1d deficiency was associated with decreased T cell production of type 2 cytokines and increased or unchanged type 1 cytokines. These findings indicate a regulatory role of CD1d in inflammatory dermatitis. Understanding the mechanisms by which CD1d deficiency results in splenic T cell expansion and cytokine alterations, with increased dermal infiltration of dendritic cells and lymphocytes in MRL-lpr/lpr mice, will have implications for the pathogenesis of inflammatory skin diseases. 相似文献
6.
Dunn GP Bruce AT Sheehan KC Shankaran V Uppaluri R Bui JD Diamond MS Koebel CM Arthur C White JM Schreiber RD 《Nature immunology》2005,6(7):722-729
'Cancer immunoediting' is a process wherein the immune system protects hosts against tumor development and facilitates outgrowth of tumors with reduced immunogenicity. Although interferon-gamma (IFN-gamma) is known to be involved in this process, the involvement of type I interferons (IFN-alpha/beta) has not been elucidated. We now show that, like IFN-gamma, endogenously produced IFN-alpha/beta was required for the prevention of the growth of primary carcinogen-induced and transplantable tumors. Although tumor cells are important IFN-gamma targets, they are not functionally relevant sites of the actions of the type I interferons. Instead, host hematopoietic cells are critical IFN-alpha/beta targets during development of protective antitumor responses. Therefore, type I interferons are important components of the cancer immunoediting process and function in a way that does not completely overlap the functions of IFN-gamma. 相似文献
7.
Choline acetyltransferase activity and cognitive domain scores of Alzheimer's patients 总被引:3,自引:0,他引:3
Choline acetyltransferase activity and cognitive domain scores of Alzheimer's patients. Item scores from the Mattis Dementia Rating Scale (MDRS) and the Mini-Mental State Examination (MMSE) from 389 patients with probable Alzheimer's disease were submitted to principal component analysis with orthogonal rotation. The optimal solution identified four factors that reflected the cognitive domains of attention/registration, verbal fluency/reasoning, graphomotor/praxis and recent memory. A subgroup of patients was identified for whom both the MDRS and the MMSE had been administered within the 12 months before death. Scores were assigned to these patients for the four factors. These cognitive-domain scores were then correlated with postmortem choline acetyltransferase (ChAT) activity in the medial frontal cortex, inferior parietal cortex, and hippocampus. ChAT activity in both the medial frontal and the inferior parietal cortex significantly correlated with scores on the graphomotor/praxis factor. Medial frontal ChAT also correlated significantly with the attention/registration scores. Hippocampal ChAT correlated significantly only with recent memory scores. These results are consistent with current animal research regarding the effect of selective cholinergic lesions on behavior. 相似文献
8.
We report the first case of acquired immunodeficiency syndrome (AIDS)-related primary hepatic leiomyosarcoma in a 9-year-old girl. The pathologic diagnosis was made on a partial hepatectomy specimen and was confirmed by immunohistochemistry and electron microscopy. No human immunodeficiency virus-related nucleic acid was identified in tumor cells by in situ hybridization. Review of the AIDS-related literature reveals a rising incidence of tumors of smooth muscle origin in human immunodeficiency virus-infected patients. This case study details the eighth pediatric AIDS patient with a tumor of smooth muscle origin and represents the 20th and the youngest patient with primary hepatic leiomyosarcoma to be reported in the world literature. 相似文献
9.
Survey of CAG/CTG repeats in human cDNAs representing new genes: candidates for inherited neurological disorders 总被引:3,自引:2,他引:3
Neri C; Albanese V; Lebre AS; Holbert S; Saada C; Bougueleret L; Meier-Ewert S; Le Gall I; Millasseau P; Bui H; Giudicelli C; Massart C; Guillou S; Gervy P; Poullier E; Rigault P; Weissenbach J; Lennon G; Chumakov I; Dausset J; Lehrach H; Cohen D; Cann HM 《Human molecular genetics》1996,5(7):1001-1009
10.
J. M. Maarek G. Jarry J. Crowe M. -H. Bui D. Laurent 《Medical & biological engineering & computing》1986,24(4):407-414
A Monte Carlo model has been developed to study the propagation of an ultrashort light pulse through a heterogeneous thick
biological specimen. A circular blood vessel is moved within a tissular slab to simulate biological specimen scanning using
a picosecond laser source and a collimated ultrafast multichannel opticl shutter. Features of the transmitted light are computed
for each position of the blood vessel. The computer program gives an account of the transmitted photons, the flight time which
does not exceed straightforward crossing time plus time gate of known duration. A small blood vessel (radius R=2 mm) placed
in a 40 mm thick slab is easily located when a time gate of 10 ps duration is employed. Such a time gate also allows the detection
of a middle-sized vessel (R=4 mm) embedded in a thicker sample (80 mm). The contrast computed for the transmittance profile
is greatly improved when a time gate is used. In addition, shifting of the blood vessel towards the unilluminated side of
the sample decreases the contrast. We demonstrate that the time selection process may provide a substantial improvement to
the laser tomoscopy technique when used for imaging biological media. 相似文献