全文获取类型
收费全文 | 1056篇 |
免费 | 59篇 |
国内免费 | 2篇 |
专业分类
耳鼻咽喉 | 4篇 |
儿科学 | 13篇 |
妇产科学 | 14篇 |
基础医学 | 60篇 |
口腔科学 | 15篇 |
临床医学 | 122篇 |
内科学 | 300篇 |
皮肤病学 | 34篇 |
神经病学 | 84篇 |
特种医学 | 17篇 |
外科学 | 208篇 |
综合类 | 16篇 |
一般理论 | 1篇 |
预防医学 | 82篇 |
眼科学 | 22篇 |
药学 | 68篇 |
中国医学 | 14篇 |
肿瘤学 | 43篇 |
出版年
2023年 | 17篇 |
2022年 | 33篇 |
2021年 | 66篇 |
2020年 | 28篇 |
2019年 | 33篇 |
2018年 | 44篇 |
2017年 | 25篇 |
2016年 | 40篇 |
2015年 | 32篇 |
2014年 | 41篇 |
2013年 | 71篇 |
2012年 | 90篇 |
2011年 | 90篇 |
2010年 | 40篇 |
2009年 | 37篇 |
2008年 | 81篇 |
2007年 | 67篇 |
2006年 | 37篇 |
2005年 | 45篇 |
2004年 | 31篇 |
2003年 | 24篇 |
2002年 | 22篇 |
2001年 | 5篇 |
2000年 | 7篇 |
1999年 | 8篇 |
1998年 | 5篇 |
1997年 | 3篇 |
1996年 | 3篇 |
1995年 | 2篇 |
1993年 | 2篇 |
1992年 | 3篇 |
1991年 | 4篇 |
1990年 | 6篇 |
1989年 | 3篇 |
1988年 | 6篇 |
1987年 | 9篇 |
1986年 | 9篇 |
1985年 | 6篇 |
1984年 | 8篇 |
1983年 | 5篇 |
1982年 | 2篇 |
1981年 | 2篇 |
1974年 | 1篇 |
1969年 | 2篇 |
1967年 | 3篇 |
1966年 | 10篇 |
1965年 | 3篇 |
1963年 | 1篇 |
1946年 | 1篇 |
1945年 | 1篇 |
排序方式: 共有1117条查询结果,搜索用时 15 毫秒
141.
Cognitive therapy is now widely recommended for the treatment of schizophrenia. However, little is known about factors predicting
good outcome. We are describing separate sub-analyses of two randomized controlled trials of Cognitive Behaviour Therapy for
schizophrenia. In one trial expert therapists provided therapy while in the second trial brief therapy was provided by trained
nurses. In both trials psychopathology was assessed using the Comprehensive Psychopathological Rating Scale (CPRS) and the
Health of the Nation Outcome Scale (HoNOS). Insight, delusions, hallucinations and negative and positive symptoms were also
measured. In brief therapy trial higher levels of insight and high CPRS global impression score predicted good outcome in
the CBT group. Analyses using similar variables did not reveal any specific predictors for good outcome in the second trial. 相似文献
142.
Ganglioside content of astroglia and neurons isolated from maturing rat brain: consideration of the source of astroglial gangliosides 总被引:1,自引:0,他引:1
Previous biochemical and histochemical studies have failed to clarify the nature or quantity of gangliosides in CNS astrocytes. Using improved methodologies for bulk isolation of both neurons and astrocytes as well as for ganglioside purification, we find significantly higher ganglioside concentration in astrocytes and very similar thin-layer chromatography (TLC) patterns for the two cell types. However, in vivo labeling of glycoconjugates via intracerebral injection of [3H]glucosamine prior to cell isolation revealed a different picture: whereas glycoproteins were well-labeled in both cell types after labeling periods of 1-2 h, gangliosides were appreciably labeled only in neurons. With longer time periods (8-48 h) between injection and sacrifice, there was convergence of specific radioactivity of gangliosides from the two isolated cell preparations. These changes are compared to those observed in synaptosomes and microsomes that were isolated simultaneously. The results suggest limited ganglioside synthetic ability in astrocytes as compared to neurons, a conclusion supported by assay of UDP-galNAc:GM3 N-acetylgalactosaminyltransferase in the isolated cells. Nevertheless, the presence of ganglioside GM1 in a substantial portion of bulk-isolated astrocytes was demonstrated by indirect immunofluorescent detection of cholera toxin binding. Ideas on the reconciliation of these apparently contradictory phenomena, including the possibility of intercellular transfer and/or phagocytosis are discussed. 相似文献
143.
A case of regenerated splenosis 20 years after splenectomy masquerading as a gastric fundic mass is reported. Several endoscopic examinations revealed an extramucosal extrinsic mass in the gastric fundus and a chain of small ulcers high along (he lesser curvature. Radionuclide technetium scan and CT scan accurately detected the regenerated splenic tissue indenting the gastric fundus and thus obviated the need for angiography and exploratory surgery. 相似文献
144.
Oligodendroglia isolated from adult bovine brain by the method of Farooq et al. could be plated on polylysine-coated plastic dishes with an efficiency of 55–80%, and maintained in culture for as long as 4 months. The addition of cytosine arabinoside to the nutrient medium resulted in cultures that were approximately 90% oligodendroglia and 10% large fibroblasts. From 50 g of white matter 100 − 160 × 106 oligodendroglia, containing approximately 6–10 mg protein, could be obtained in culture. These small round cells started to send out processes at 5 days in vitro and by 2 weeks they formed an extensive network of processes. By immunofluorescence, all cells of this morphology were positive for galactocerebroside (GC) and myelin basic protein (MBP), and negative for glial filament protein and fibronectin. Most of the large flat cells were positive for fibronectin and negative for GC, MBP and glial filament protein. As the cultures aged the oligodendroglia tented to clump and blebs formed on the surface of both perikarya and processes. By 4 months they showed evidence of degeneration and detached from the substrate. Electron microscopic examination showed that the cells had the appearance typical of oligodendroglia in situ. The somata were round to elliptical, with eccentrically placed nuclei, and were larger than freshly isolated cells. They grew directly on the substrate or on the surface of the fibroblasts. In older cultures the cells formed tight nests. The somata were enveloped by sheets of oligodendrocyte cytoplasm, sometimes having a myelin-like appearance. Gap junctions and small desmosomes were seen between oligodendroglial processes and between oligodendroglia and fibroblasts. The cytoplasm was characterized by a prominent Golgi apparatus, many mitochondria and lysosomes, scattered rough endoplasmic reticulum, free ribosomes, frequent centrioles and an abundance of microtubules. In cells from older cultures large vacuoles were common, and rarely they had multilamellar walls with alternating major and minor dense lines resembling myelin. 相似文献
145.
Farooq P. Agha M.D. Timothy T. Nostrant M.D. Richard G. Fiddian-Green M.D. 《The American journal of gastroenterology》1984,79(4):319-321
A case of massive phytobezoar in the right colon due to psyllium seed husks causing complete gastric outlet obstruction by extrinsic compression is reported. The diagnostic dilemma of unusually large size of the bezoar and nonsurgical removal are unique features of this case. 相似文献
146.
Immunosuppressive property of normal human seminal plasma has been demonstrated on various in vitro immune parameters such as, blast transformation of lymphocytes with Phytohemagglutinin (P), Concanavalin A and Lipopolysaccharide, E & EAC rosette formation and mixed lymphocyte culture. The immunosuppression appears to be a T-cell mediated phenomenon. Analysis of semen samples obtained from 86 donors, comprising azoospermic, oligospermic, normospermic and polysperrnic individuals, suggests that immunosuppression of the seminal plasma has no correlation with either the sperm density or the protein content of seminal plasma. The possible implication of the immunosuppressive activity in the development of acquired immuno-deficiency syndrome is also discussed. 相似文献
147.
With the advent of autosuture devices, gastric partitioning procedures have recently become popular surgical treatment of morbid obesity. One such procedure is Gomez gastroplasty. Using an autosuture device a small gastric fundal pouch, having a reservoir capacity of 60 ml and communicating with the remaining stomach through a 12 mm stoma is created along the greater curvature of the stomach. A 3-0 polyprolene internal seromuscular suture is used to reinforce the stoma without incising the stomach. This gastroplasty is extremely attractive because of the disarming simplicity of the procedure and its noninterruption of the normal sequence of the digestive tract.This report is based on a joint review of 280 cases subjected to Gomez gastroplasty to combat morbid obesity. Postoperative radiological evaluation and the spectrum of observed complications are herein described. 相似文献
148.
Because of increased safety concerns about synthetic antioxidants, exploitation of cheaper and safer sources of antioxidants based on natural origin is the focus of research nowadays. Rhazya stricta is a medicinally important plant native to South Asia. Extraction of antioxidants was carried out in different solvent systems, i.e., water, 80% methanol, 70% ethanol, and diethyl ether. The methanolic extract exhibited the highest total phenolic content among the extracts; therefore for further studies the methanolic extract was employed. Antioxidant activity measurement in the linoleic acid system, metal chelating activity, reducing power, scavenging effect on 1,1-diphenyl-2-picrylhydrazyl free radical, and superoxide anion radical scavenging activity were taken as the parameters for assessment of antioxidant potential of methanolic extracts. Results were compared with alpha-tocopherol and the synthetic antioxidant butylated hydroxyanisole. The antioxidant potential of methanolic extracts of R. stricta leaves was comparable with previously exploited potent antioxidants and is strongly concentration dependent. 相似文献
149.
Ismail K. Dawood M. Farooq G. O. Unrau Luis C. Miguel B. C. Dazo 《Bulletin of the World Health Organization》1965,32(2):261-268
Parallel field trials have been conducted in Egypt to determine the relative efficacy for bilharziasis control of some new molluscicides and one in current use. In the field trials, Bayluscide and two formulations of ICI 24223 were compared with each other and with sodium pentachlorophenate. All the compounds were highly molluscicidal, but when judged on a basis of cost, ease of application and labour required, Bayluscide appeared to perform better than the others. If improved formulations of ICI 24223 could be made, the choice would be more difficult. Sodium pentachlorophenate, though effective, required high concentrations, and difficulties were encountered in handling the chemical. 相似文献
150.