全文获取类型
收费全文 | 153642篇 |
免费 | 11708篇 |
国内免费 | 3528篇 |
专业分类
耳鼻咽喉 | 1172篇 |
儿科学 | 2906篇 |
妇产科学 | 1903篇 |
基础医学 | 11256篇 |
口腔科学 | 5875篇 |
临床医学 | 14751篇 |
内科学 | 17206篇 |
皮肤病学 | 1901篇 |
神经病学 | 14134篇 |
特种医学 | 4358篇 |
外国民族医学 | 22篇 |
外科学 | 13682篇 |
综合类 | 25497篇 |
现状与发展 | 16篇 |
一般理论 | 7篇 |
预防医学 | 16706篇 |
眼科学 | 2191篇 |
药学 | 15568篇 |
257篇 | |
中国医学 | 11101篇 |
肿瘤学 | 8369篇 |
出版年
2024年 | 504篇 |
2023年 | 2530篇 |
2022年 | 4500篇 |
2021年 | 6197篇 |
2020年 | 6345篇 |
2019年 | 4926篇 |
2018年 | 4667篇 |
2017年 | 4940篇 |
2016年 | 5391篇 |
2015年 | 5137篇 |
2014年 | 10213篇 |
2013年 | 12793篇 |
2012年 | 9872篇 |
2011年 | 10566篇 |
2010年 | 8621篇 |
2009年 | 7833篇 |
2008年 | 7407篇 |
2007年 | 7425篇 |
2006年 | 6688篇 |
2005年 | 5662篇 |
2004年 | 4722篇 |
2003年 | 4145篇 |
2002年 | 3375篇 |
2001年 | 2836篇 |
2000年 | 2423篇 |
1999年 | 1958篇 |
1998年 | 1750篇 |
1997年 | 1654篇 |
1996年 | 1389篇 |
1995年 | 1260篇 |
1994年 | 1203篇 |
1993年 | 1051篇 |
1992年 | 923篇 |
1991年 | 888篇 |
1990年 | 689篇 |
1989年 | 638篇 |
1988年 | 636篇 |
1987年 | 595篇 |
1986年 | 545篇 |
1985年 | 733篇 |
1984年 | 606篇 |
1983年 | 384篇 |
1982年 | 446篇 |
1981年 | 379篇 |
1980年 | 354篇 |
1979年 | 265篇 |
1978年 | 200篇 |
1977年 | 179篇 |
1976年 | 134篇 |
1975年 | 65篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
Summary A total of 824 chain-saw operators who were employed in felling trees in the forestry industry were exposed to local vibration, which produced peripheral blood-flow disorders and lesions in the joints and hand bones. In the last 10 years, they have undergone 24-day balneoclimatic treatment at the Kolobrzeg Health Resort. It was found that a stay in the spa and certain balneological treatments exert a favorable effect on the peripheral blood-flow disorders produced by the local vibration of chain saws. The symptoms (chills and numbing of the fingers, etc.) disappeared in nearly 40% of these workers. An improvement in the objective indices of the peripheral circulation (thermographic and plethysmographic tests) was observed in about 90% of patients treated with brine baths combined with underwater vibratory massage (rotatory) or brine baths alone. The brine bath and vibratory massage have a direct beneficial influence on the peripheral blood flow of pectoral limbs. 相似文献
993.
本文定义了一类“近乎双线性”系统。可用以近似一类奇异摄动双线性系统,而且可以描述某些实际工业对象。并发现其控制器的设计较方便。文中还给出了一种简单的反馈控制器的设计方法。又对一类多输入双线性系统,提出一种设计反馈控制器的改进方案,根据Lyapunov定理得到一非线性反馈控制律。以上设计方法分别对某合成氨反应器作了应用研究,仿真结果表明了方法的有效性。 相似文献
994.
我院多年来应用千捶膏和生肌玉红膏治疗感染性伤面。千捶膏用于去腐,生肌玉红膏用于生新。据我们观察二药有较强的抗感染作用,尤其有抗绿脓感染作用。应用千捶膏可以较快地达到脱腐作用,应用生肌玉红膏可以促进肉芽增生,达到伤面早期愈合,值得推广。 相似文献
995.
Summary The handling of five amines by the extraneuronal deaminating system was studied in perfused hearts of rats (pretreated with reserpine; COMT and neuronal uptake inhibited). Hearts were perfused with 50 nmol/l 3H-noradrenaline for 30 min, in the presence of increasing concentrations of unlabelled (–)-adrenaline, (–)-noradrenaline, dopamine, tyramine and 5-HT. IC50's were determined as those concentrations of unlabelled amines which halved the steady-state rate of deamination of 3H-noradrenaline. After correction for changes in the tissue/medium ratio for 3H-noradrenaline, half-saturating outside concentrations were obtained. They increased in the order (–)-adrenaline (15 mol/l) — tyramine — dopamine — noradrenaline —5-HT (53 mol/l). The V
max for extraneuronal deamination was determined for 3H-(–)-adrenaline, 3H-(–)-noradrenaline and 3H-dopamine, as well as (by HPLC and electrochemical detection) for tyramine and 5-HT. It was low for (–)-adrenaline, intermediate for (–)-noradrenaline, dopamine and 5-HT, high for tyramine. For the three catecholamines the half-saturating outside concentrations of the extraneuronal deaminating system clearly exceeded those for the extraneuronal O-methylating system of the same organ (see Grohmann and Trendelenburg 1985), although the two enzymes appear to co-exist in the same cells, so that the same transport system is involved.Abbreviations COMT
catechol-O-methyl transferase
- DOMA
dihydroxymandelic acid
- DOPEG
dihydroxyphenylglycol
- 5-HT
5-hydroxytryptamine
- MAO
monoamine oxidase
Supported by the Deutsche Forschungsgemeinschaft (SFB 176)
Send offprint requests to U. Trendelenburg 相似文献
996.
Rats with impaired active avoidance induced by chronic (9 weeks) administration of ethanol were studied. Angiotensin II (ANG II) administered (ICV, 2.0 g) 12 h after the withdrawal of the alcohol not only neutralized the toxic effect of ethanol but also improved learning. When administered on the 5th day after ethanol withdrawal, the effect of ANG II was weaker. Tests of stereotypy and catalepsy were used to study the possible role of the dopaminergic system in this action of ANG II. It was shown that both chronic alcohol treatment and ANG II alone increased apomorphine (1 mg/kg) and amphetamine (7.5 mg/kg) stereotypy but the effects of ANG II were greater. ANG II did not change the stereotypy induced by amphetamine but increased the stereotypy induced by apomorphine in the group of animals chronically treated with alcohol. Haloperidol — induced catalepsy was reduced in these rats. ANG II alone intensified catalepsy and eliminated the effect of ethanol. Both ANG II and alcohol increased striatal dopamine (DA) concentration. This effect of ANG II was significantly greater in the animals chronically treated with alcohol. The above changes were not observed after the DA level had been reduced by alpha-methyl-p-tyrosine (250 mg/kg), nor were changes observed in the striatal DOPAC. The results suggest involvement of the central dopaminergic system in the effect of ANG II on the ethanol — induced impairment of acquisition of active avoidance but, however, the results of the biochemical determinations of DA turnover do not provide an explanation of these changes. 相似文献
997.
V. G. Wilson M. Grohmann U. Trendelenburg 《Naunyn-Schmiedeberg's archives of pharmacology》1988,337(4):397-405
Summary The O-methylation and accumulation of 3H-isoprenaline in slices of the rat cerebral cortex were studied before and after inhibition of COMT. 1. Inhibition of COMT by mol/l U-0521 virtually abolished the O-methylation and increased the accumulation of 3H-isoprenaline; hence, there is evidence for the existence of a central O-methylating system (with a transport mechanism and intracellular COMT). 2. Experiments were carried out with selective uptake inhibitors for uptake, (cocaine and desipramine) or uptake2 (corticosterone and OMI), with phenoxybenzamine (known to inhibit both carriers) and with changes in the ionic composition of the incubation medium. They revealed that the central carrier differed from both, uptake, and uptake2, although exhibiting some resemblance with uptake2 (lack of dependence on Na+ and Cl–, sensitivity to K+ and phenoxybenzamine, ability to transport 3H-isoprenaline). 3. Although the central carrier was rather sensitive to inhibition by beta-adrenoceptor antagonists (propranolol, carteolol), the effect of propranolol was not stereoselective; hence, beta-adrenoceptors do not seem to be involved. 4. Virtually identical IC30-values were obtained for inhibitors, when determined with or without inhibition of COMT. Only OMI was found to inhibit COMT as well as the central transport system; hence it was more potent in inhibiting the O-methylation than the accumulation of 3H-isoprenaline. 5. IC50-values (against initial rates of accumulation of 3H-isoprenaline; COMT inhibited) were determined for various substrates and inhibitors of peripheral uptake2. There was no correlation with the IC50-values determined earlier for uptake2 in rat heart (Grohmann and Trendelenburg 1984). 6. Unlabelled catecholamines half saturated the intracellular COMT when slices were incubated with 0.22 mol/l [(±)-dobutamine] to 4.9 mol/l [(–)-noradrenaline]. As the presence of unlabelled catecholamines increased tissue levels of 3H-isoprenaline, catecholamines are substrates of the central carrier. 7. The carrier of the central O-methylating system differs from uptake2 of peripheral organs, although it resembles the peripheral carrier in some respects.Abbreviations COMT
catechol-O-methyl transferase
- DOPEG
dihydroxyphenylglycol
- MAO
monoamine oxidase
- OMI
3-Omethyl-isoprenaline
Supported by the Deutsche Forschungsgemeinschaft (Tr 96 and SFB 176) and by a scholarship of the Royal Society for V. G. Wilson. Some of the results were presented to the British Pharmacological Society (Trendelenburg and Wilson 1986) 相似文献
998.
术后快速康复对全膝关节置换术后功能的影响 《首都医科大学学报》2023,44(1):167-171
目的 通过对比全膝关节置换术(total knee arthroplasty, TKA)患者术后功能结果,探讨术后快速康复(enhanced recovery after surgery, ERAS)方案对TKA术后功能的影响。方法 以首都医科大学附属北京朝阳医院2010年1月1日到2021年12月31日1 881例诊断为膝关节骨关节炎的住院患者为研究对象,根据是否应用ERAS方案分为ERAS组和对照组。收集两组患者基本信息、术前和术后1个月的膝关节活动度、美国膝关节协会评分(American Knee Society Score, KSS)、西大略湖和麦克马斯特大学骨关节炎评分(the Western Ontario and McMaster Universities, WOMAC)以及术后1个月患者满意度。结果 实施术后快速康复方案后,ERAS组住院时间及住院费用明显低于对照组,组间差异有统计学意义(P<0.01)。术后1个月,ERAS组患者KSS临床和功能评分以及膝关节活动度明显优于对照组,患者术后满意度明显高于对照组,组间差异有统计学意义(P<0.05);而术后1个... 相似文献
999.
颈痛在临床上常由颈椎退行性疾病引起,易对患者颈部功能及生活质量造成不良影响。为提供最佳、有效的诊断及治疗方案,2019年美国国家健康科学大学发表了《最佳实践建议:颈痛患者的整脊治疗管理》。课题组在充分研读最新版指南诊治内容的基础上,从诊断、治疗、注意事项3个方面进行解读,同时检索相关文献,纵向对比多个高质量颈痛相关指南,从生物力学及神经生物学方面分析手法治疗颈痛的科学性,并结合中国诊疗现状分析认为其推荐的手法治疗及诊疗流程在中国具有可行性,基于此认为将国内外现有的循证医学证据结合中国传统医学能指导临床实践。 相似文献
1000.
分级诊疗制度是优化基本医疗卫生制度的重要步骤,但落地实施时遇到阻碍,因存在转诊标准不一、空间不连贯和时间滞后等问题,医联体模式推进存在难度。上海市浦东新区人民医院联合7家社区卫生服务中心,构建了一套以信息化为支撑的川沙医联体慢性肾脏病(CKD)专病精准分级诊疗管理方案。以CKD病种为例,基于指南梳理CKD患者的疾病管理规律,建立医疗信息联通共享、转诊规则标准的CKD专病分级诊疗知识库,设计区域CKD专病分级诊疗系统,构建了基于医院-社区联动管理的专病分级诊疗一体化管理模型。且实证应用评价显示,基于CKD知识库的专病分级诊疗模式,可以精准定位易发和高危人群,及时筛查评估CKD早期患者,提升CKD患者的健康管理和诊疗效率。 相似文献