全文获取类型
收费全文 | 1096篇 |
免费 | 56篇 |
国内免费 | 24篇 |
专业分类
耳鼻咽喉 | 22篇 |
儿科学 | 66篇 |
妇产科学 | 8篇 |
基础医学 | 99篇 |
口腔科学 | 54篇 |
临床医学 | 183篇 |
内科学 | 190篇 |
皮肤病学 | 4篇 |
神经病学 | 62篇 |
特种医学 | 210篇 |
外科学 | 76篇 |
综合类 | 19篇 |
一般理论 | 2篇 |
预防医学 | 87篇 |
眼科学 | 6篇 |
药学 | 60篇 |
肿瘤学 | 28篇 |
出版年
2022年 | 5篇 |
2021年 | 9篇 |
2020年 | 5篇 |
2019年 | 7篇 |
2018年 | 12篇 |
2017年 | 6篇 |
2016年 | 17篇 |
2015年 | 11篇 |
2014年 | 36篇 |
2013年 | 29篇 |
2012年 | 23篇 |
2011年 | 24篇 |
2010年 | 22篇 |
2009年 | 20篇 |
2008年 | 26篇 |
2007年 | 41篇 |
2006年 | 35篇 |
2005年 | 42篇 |
2004年 | 23篇 |
2003年 | 29篇 |
2002年 | 22篇 |
2001年 | 41篇 |
2000年 | 24篇 |
1999年 | 27篇 |
1998年 | 39篇 |
1997年 | 32篇 |
1996年 | 43篇 |
1995年 | 30篇 |
1994年 | 26篇 |
1993年 | 29篇 |
1992年 | 23篇 |
1991年 | 22篇 |
1990年 | 36篇 |
1989年 | 37篇 |
1988年 | 54篇 |
1987年 | 37篇 |
1986年 | 25篇 |
1985年 | 26篇 |
1984年 | 20篇 |
1983年 | 20篇 |
1982年 | 25篇 |
1981年 | 12篇 |
1980年 | 12篇 |
1979年 | 10篇 |
1977年 | 13篇 |
1976年 | 18篇 |
1975年 | 10篇 |
1974年 | 9篇 |
1971年 | 5篇 |
1967年 | 4篇 |
排序方式: 共有1176条查询结果,搜索用时 15 毫秒
1.
Hysterosalpingography was performed in 31 patients by means of a low-dose scanning-beam digital radiographic system. The technique permits adequate evaluation of gynecologic abnormalities while allowing significant reduction in radiation: 2.4-mR (6.1 X 10(-7) C/kg) exposure to the skin and 0.7-mrad (7 X 10(-6) Gy) mean dose to the ovaries per image obtained. Sixteen patients demonstrated readily recognizable and documented abnormalities, corroborated by laparoscopy, laparotomy, or other supportive evidence. 相似文献
2.
3.
4.
The two defining features of somatization are numerous self-reported physical symptoms and excessive health care seeking. This may be due to a lowered perceptual threshold for perceiving and reporting bodily symptoms, amplification or misinterpretation of those symptoms, or underlying psychiatric disturbance. Recurrent pain is the most common somatic symptom reported. True somatization disorder is very rare (<1%) and requires a DSM-III-R diagnosis of at least 13 different physical symptoms which cannot be explained by, or are in gross excess of physical findings, and have caused the patients to seek health care or alter their lifestyles. However, researchers have argued that a spectrum of severity for somatization exists, and this is supported by epidemiological research. Available data also indicate that behavioural interventions may show long-term cost-effectiveness in the management of chronic pain. Chronic pain dysfunction appears to place a disproportionate burden on overall health care expenditure for chronic pain patients. 相似文献
5.
6.
Clinical diagnostic criteria for TMD. New classification permits multiple diagnoses. 总被引:21,自引:0,他引:21
E L Truelove E E Sommers L LeResche S F Dworkin M Von Korff 《Journal of the American Dental Association (1939)》1992,123(4):47-54
One of the first to permit multiple diagnoses, this new TMD classification scheme offers guidelines for clinicians and those conducting clinical field studies. The scheme was applied to a TMD population, with control subjects. 相似文献
7.
Noninvasive metabolic magnetic resonance (MR) imaging reflecting glucose metabolism in the aldose-reductase-sorbitol (ARS) pathway was performed in the rabbit head; after administration of the fluorinated glucose analogue 3-fluoro-3-deoxy-D-glucose (3FD-glucose), fluorine-19 images were generated. Images of 3FD-glucose showed significant 3FD-glucose uptake by adipose tissue, indicating its buffering effects in case of excess loads of glucose. Images of 3-fluoro-3-deoxy-D-sorbitol (3FD-sorbitol) demonstrated the spatial distribution of aldose reductase activities and significant sorbitol accumulation in the lens. Images of 3-fluoro-3-deoxy-D-fructose (3FD-fructose) showed preferential uptake of fructose by muscle tissue. The extremely low toxicity of 3FD-glucose indicates promise for its clinical application in metabolic imaging. 相似文献
8.
Jonathan L. Katz Jeffrey M. Witkin Steven I. Dworkin Linda A. Dykstra Richard B. Carter 《Drug development research》1990,20(1):31-41
Effects of daily administrations of d-amphetamine were studied on key peck responses of pigeons maintained under a multiple fixed-interval 2-min, fixed-ratio 30-responseschedule. Under the fixed-interval schedule, a pause was followed by a transition to increasing rates of responding until food presentation. Under the fixed-ratio schedule, higher sustained rates of responding were maintained. Low to intermediate doses (0.3-1.0 mg/kg) of d-amphetamine changed the temporal patterns and occasionally increased rates of responding under the fixed-interval schedule. Higher doses decreased rates of responding under bothschedules. With daily injections of 1.0 mg/kg d-amphetamine prior to experimental sessions, the effects of this dose on rates and patterns of responding were attenuated, and d-anphetamine dose-effect curves were shifted to the right, primarily under the fixed-ratio schedule. Similar results were obtained with daily presession injections of 5.6 mg/kg d-amphetamine in a second group of pigeons, except that rates of responding under both schedules were decreased by this daily dose, and did not return completely to control values with repeated injections. In a third group of pigeons, 1.0 mg/kg d-amphetamine administered daily, after experimental sessions, did not alter dose-effect functions for d-amphetamine. In a second experiment, pigeons were trained to peck one response key when given 1.0 mg/kg d-amphetamine and a different key when given presession water injections. Increasing doses of d-amphetamine produced incresing percentages of d-amphetamine-key responses. Repeated administration of 5.6 mg/kg d-amphetamine shifted these dose-effect functions to the right one-half log unit. Results suggested that decreases in reinforcement frequency are not a necessary condition for the development of behavioral tolerance to d-amphetamine. 相似文献
9.
目的:血小板衍生生长因子在平滑肌细胞的表型转化过程中起重要作用。观察大鼠移植心脏组织中血小板衍生生长因子AmRNA表达的变化及雷帕霉素的干预效应。方法:实验于2005-10/2006-01在中南大学湘雅二医院胸心外科实验室完成。将60只SD大鼠、24只Wistar大鼠按随机数字表法分为3组:①同系移植组:供、受体各12只,均为SD大鼠。②异系移植组:供体为Wistar大鼠(n=24),受体为SD大鼠(n=24),受体大鼠随机分为雷帕霉素组(n=12)和环孢霉素组(n=12),术后分别给予雷帕霉素1.25mg/(kg·d)灌胃及环孢霉素A10mg/(kg·d)皮下注射,给药60d,给药结束后留取移植心脏待检。③另12只SD大鼠直接取心脏组织作为正常对照组。指标检测:①对移植心脏组织行VanGieson染色后采用Miassystem4.1医学图像分析管理系统分析血管狭窄程度。②应用反转录-聚合酶链反应检测血小板衍生生长因子AmRNA在移植心脏组织中的表达情况。结果:36只受体SD大鼠及12只正常SD大鼠全部进入结果分析,无脱失。①同系移植组、环孢霉素组及雷帕霉素组大鼠的冠状动脉狭窄指数均显著高于正常对照组[(13.12±0.72)%,(62.45±8.12)%,(28.91±3.24)%,(0.09±0.02)%(P<0.01)],环孢霉素组及雷帕霉素组高于同系移植组(P<0.05),环孢霉素组高于雷帕霉素组(P<0.01)。②正常对照组、同系移植组、环孢霉素组及雷帕霉素组大鼠的血小板衍生生长因子AmRNA相对含量分别为0.19±0.06,0.21±0.08,1.12±0.22及0.47±0.11,环孢霉素组、雷帕霉素组显著高于同系移植组(P<0.01),环孢霉素组高于雷帕霉素组(P<0.05)。结论:血小板衍生生长因子AmRNA的高表达与移植心脏的血管硬化有关;雷帕霉素具有预防大鼠心脏移植物血管病变的作用,其作用可能与抑制心脏组织中血小板衍生生长因子AmRNA的表达有关。 相似文献
10.