全文获取类型
收费全文 | 43155篇 |
免费 | 4386篇 |
国内免费 | 871篇 |
专业分类
耳鼻咽喉 | 302篇 |
儿科学 | 884篇 |
妇产科学 | 549篇 |
基础医学 | 3186篇 |
口腔科学 | 1495篇 |
临床医学 | 4165篇 |
内科学 | 5558篇 |
皮肤病学 | 467篇 |
神经病学 | 3314篇 |
特种医学 | 1263篇 |
外国民族医学 | 3篇 |
外科学 | 3410篇 |
综合类 | 4767篇 |
现状与发展 | 5篇 |
一般理论 | 2篇 |
预防医学 | 7625篇 |
眼科学 | 572篇 |
药学 | 3310篇 |
27篇 | |
中国医学 | 4459篇 |
肿瘤学 | 3049篇 |
出版年
2024年 | 158篇 |
2023年 | 981篇 |
2022年 | 1419篇 |
2021年 | 1805篇 |
2020年 | 1766篇 |
2019年 | 1748篇 |
2018年 | 1708篇 |
2017年 | 1625篇 |
2016年 | 1490篇 |
2015年 | 1333篇 |
2014年 | 3112篇 |
2013年 | 3146篇 |
2012年 | 2507篇 |
2011年 | 2669篇 |
2010年 | 2049篇 |
2009年 | 1959篇 |
2008年 | 2227篇 |
2007年 | 2276篇 |
2006年 | 2034篇 |
2005年 | 1704篇 |
2004年 | 1403篇 |
2003年 | 1338篇 |
2002年 | 1041篇 |
2001年 | 957篇 |
2000年 | 767篇 |
1999年 | 664篇 |
1998年 | 482篇 |
1997年 | 517篇 |
1996年 | 397篇 |
1995年 | 412篇 |
1994年 | 357篇 |
1993年 | 297篇 |
1992年 | 297篇 |
1991年 | 261篇 |
1990年 | 220篇 |
1989年 | 203篇 |
1988年 | 193篇 |
1987年 | 154篇 |
1986年 | 122篇 |
1985年 | 114篇 |
1984年 | 100篇 |
1983年 | 67篇 |
1982年 | 65篇 |
1981年 | 61篇 |
1980年 | 57篇 |
1979年 | 32篇 |
1978年 | 29篇 |
1977年 | 26篇 |
1976年 | 18篇 |
1975年 | 18篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
Heterogeneity in the Dorsal Subiculum of the Rat. Distinct Neuronal Zones Project to Different Cortical and Subcortical Targets 总被引:2,自引:0,他引:2
The aim of the present study was to relate the distribution of efferents of the dorsal subiculum to their origin along the proximodistal axis of the subiculum. The distribution of subicular projections was studied in detail by means of the sensitive anterograde tracer Phaseolus vulgaris-leucoagglutinin (PHA-L), and the precise origin of these projections analysed with retrogradely transported fluorescent tracers, using double- and triple-labelling protocols. Injections of PHA-L in the proximal part of the dorsal subiculum, i.e. that part which borders field CA1, result in labelling of the infralimbic, entorhinal and perirhinal cortices, the nucleus accumbens and the lateral septal region, the interanteromedial nucleus of the thalamus, the core of the nucleus gelatinosus, and the mammillary nuclei, in particular in the rostral parts of the medial nucleus. In contrast, injections in the distal part of the dorsal subiculum, i.e. that part which borders the presubiculum, give rise to labelling in the retrosplenial and postrhinal cortices, the presubiculum, the anterior thalamic complex, the shell of the nucleus gelatinosus, and the mammillary nuclei, preferentially in the caudal part of the medial nucleus. The results of injections of different retrograde tracers, simultaneously placed in two or three targets of the subicular efferents, confirm the results of the anterograde tracing experiments. Moreover, they clearly demonstrate that the population of subicular neurons which, for example, projects to the nucleus accumbens and the interanteromedial nucleus of the thalamus is almost completely segregated from the population that projects to the retrosplenial cortex and the anterior complex of the thalamus. Thus within the dorsal subiculum, populations of neurons can be differentiated so that each population projects to a unique set of target structures. These cell populations are differentially positioned along the proximo-distal axis. In view of additional evidence indicating that some of the major afferents to the subiculum are organized along the same axis, we suggest that the heterogeneity of the dorsal subiculum along the proximo-distal axis reflects a general organizational characteristic of this hippocampal field. 相似文献
92.
G. Geminiani B. M. Cesana G. Scigliano P. Soliveri F. Girotti P. Giovannini T. Caraceni 《Acta neurologica Scandinavica》1990,81(5):397-401
A retrospective study of variations of therapeutic response (dyskinesia and on-off phenomenon) in Parkinson's disease was conducted on 278 patients treated with levodopa for at least 6 months and hospitalized at National Neurological Institute "C. Besta" of Milan between 1974 and 1984. Variations of therapeutic response (TRV) were present in 105 of 278 patients; in this group, age at illness onset was significantly lower, while duration of levodopa treatment and also duration of illness were longer than in the group of patients without TRV. Multiple logistic regression analysis showed that the most important variables were age at illness onset and duration of treatment, but they were only modestly predictive. Other factors connected with progression of disease must also contribute to the TRV. 相似文献
93.
目的:寻求理想的建立小鼠不同深度烫伤模型的方法。方法:研制了恒温恒压电烫仪,分别以80度,0.5kg,2cm为统一的致伤温度,致伤压力,致伤直径,同时严格控制其他各个因素,以致伤时间为唯一可变因素,通过改变致伤时间,在小鼠背部建立不同深度的烫伤模型,并于烫伤后即时,4h,12,24h和48h取材病检。结果:建立浅II度,深II度及III度烫伤创面模型的致伤时间分别为5s,8s和12s;汤伤创面深度随病程逐渐加深,直至伤后24h才稳定,伤后48h的组织学改变类似伤后24h,结论:烫伤创面深度应以伤后24h创面深度稳定后的深度为诊断标准,本方法操作简单,所建模型稳定,重复性好,不失为一种建立小鼠不同深度烫伤模型的较为理想的方法。 相似文献
94.
骨关节放大摄影的临床应用和诊断价值 总被引:1,自引:0,他引:1
乐涛 《武汉大学学报(医学版)》2000,21(1):86-88
目的 :评价和比较X线放大像与普通X线平片诊断价值。方法 :对 386例患者 (男 2 6 7例 ,女 119例 )。患处原有普通X线平片部位进行X线放大摄影 ,并与原片进行对比分析。结果 :放大像发现病变阳性率为 75 .91%(2 93/ 386 ) ,普通X线平片发现病变阳性率为 5 7.5 1% (2 2 2 / 386 ) ,两者比较 ,前者的阳性率明显高于后者。结论 :对普通X线平片不能作出确切诊断的病例 ,摄X线放大像可提高诊断准确性 ,且有重要诊断价值 相似文献
95.
张基栋 《辽宁中医药大学学报》2000,(1)
探讨中药玉屏风散加味对强的松不良反应的拮抗作用及对肾病综合征Ⅰ型的病程的影响 ,将病人随机分为玉屏风散加味治疗组(37例 ) 和对照组(2 1例 ) ,观察用药后 2、4、6周自汗、心悸症状及心率变化情况及治疗后 1年内各种感染次数 ,治疗 1年后强的松服药量及 2 4小时尿蛋白定量情况。结果 :治疗第 4、6周自汗、心悸症状发生率及心率治疗组均低于对照组 ,感染次数治疗组低于对照组 ,1年未服强的松量及其 2 4小时尿蛋白量均低于对照组 ,两组数据经统计学处理有显著性差异。结论 :玉屏风散加味能明显减轻强的松引起的自汗、心悸等不良反应 ,减少感染次数 ,缩短NSI型的病程。 相似文献
96.
Objective To observe and evaluate the efficacy and safety of quinacrine sterilization.Methods A total of 572 cases of quinacrine sterilization preformed during the 4 years from 1993to 1997in Jiangsu and Guizhou Provinces were employed in this study. The efficacy and safety of quinacrine sterilization in those case were studied and evaluated, with 588 cases of surgical sterilization performed at the same time being the control group.Results Both groups were with identical demographic and gynecological characteristics. The result of multiple decrement life table analysis showed the 12th gross cumulative failure rates for quinacrine sterilization was 3. 13% and serious side effects occurred in only 2 cases accounting for O. 35%. One was ectopic pregnancy (20 months after treatment). The other was due to anaphylaxis in 10 minutes after the second insertion). No difference in the liver and nephic functions was detected and no suspected cancer cells or cancer cells were found in the two groups. 99. 6% of the 572 women interviewed accepted the quinacrine sterilization.Conclusions Quinacrine sterilization method is with high acceptability but comparatively low effectiveness. It has been proved to be a safe method of contraception in short-term. However, the safety of long-term still needs further study. 相似文献
97.
Marianne Cederblad Lisa Dahlin Olle Hagnell Kjell Hansson 《European archives of psychiatry and clinical neuroscience》1995,245(1):11-19
The Sjöbring system of personality dimensions measuring intellectual capacity, activity, impulsivity and sociability was used to study possible salutogenic (i.e. causes of health) effects. The study comprised 590 subjects investigated in 1947, 1957, 1972 and 1988–1989 in the Lundby project, an epidemiological study in Sweden. Psychiatric diagnoses were made in 1947, 1957 and 1972. Mental health was estimated in 1988–1989 using the concept love well, work well, play well and expect well. The Sjöbring dimensions were clinically assessed in 1972. Both in the concurrent study in 1972 and in the prospective study in 1988–1989 super capacity (high intellectual function), super validity (high activity level) and super solidity (low impulsivity) were statistically associated with lower frequencies of certain psychiatric diagnoses and a higher frequency of positive mental health. These variables are proposed to increase coping capacity, and therefore increase stress resilience. 相似文献
98.
Mohsen Shahsavari Gholam A. Peyman Michael R. Niesman Michael V. Miceli Jesse Jaynes 《International ophthalmology》1995,19(1):29-34
An investigation was undertaken to determine the toxicity of an intravitreal injection of a novel peptide drug, Shiva-1, in rabbits. The drug, a synthetic peptide modeled after lytic peptides secreted by certain insects, has antiproliferative and antibacterial properties. Initial in vitro experiments showed that the drug, at a concentration of 100 M, was toxic to both Y-79 retinoblastoma cells and human retinal pigment epithelial cells. A wide range of doses (6–1200 g) was injected into the rabbit vitreous in an attempt to determine the maximum tolerated dose. Retinal toxicity was evaluated clinically, by electroretinography, and by light microscopy. Some localized toxicity was evident at 200 g; all doses of 240 g and above were toxic. While the drug appears to exhibit a narrow range between effective and toxic doses, the results suggest that this and other peptides of similar design merit further investigation for the treatment of proliferative and infectious diseases of the eye.Supported in part by U.S. Public Health Service grants EY07541 and EY02377 from the National Eye Institute, the National Institutes of Health Services, Bethesda, MD, USA 相似文献
99.
Michael Klintschar 《International journal of legal medicine》1995,108(3):162-164
The short tandem repeat system FES/FPS was amplified by the polymerase chain reaction (PCR) in 211 unrelated Austrians and analysed by horizontal, non-denaturing electrophoresis. The allele distribution was in Hardy-Weinberg equilibrium. No mutations were found in 25 families (50 meioses). The mean exclusion chance was 0.49, the discriminating power 0.86 and the heterozygosity rate 74.4%. Amplification could be achieved with as little as 100 pg of high molecular weight DNA, which could be reduced to 75 pg by using 32 instead of 30 cycles. By reamplifying 1 l for another 15 cycles, the threshold could be reduced to less than 20 pg. In a degradation experiment DNA extracted from bloodstains stored for up to 24 days in a moist chamber and DNA boiled for up to 18 min could be amplified. 相似文献
100.
E. Gagneux L. Jeunet P. Vichard 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》1995,5(3):166-166
The number of femoral fractures after hip arthroplasty has increased proportionally to the number of hip arthroplasties. Eleven
university-orthopaedic centers in eastern France co-operated to review 250 femoral fractures in relation to hip prothesis.
This is the largest published review. The aims of this retrospective study were:
Les auteurs ont réalisé une étude rétrospective portant sur 250 fractures du fémur porteur d’une prothèse de hanche. Il s’agit
de la plus importante statistique publiée à ce jour. Pour ceci 11 centres hospitalo-universitaires de l’Est de la France ont
été mobilisés, dans le cadre de la 38e réunion de la S.O.T.EST. Les principaux objectifs de cette étude étaient de mettre
en évidence les facteurs favorisants de ces fractures et de dégager un protocole thérapeutique consensuel.
Présenté à la 38ème Réunion S.O.T.EST à Lons-le-Saunier du 17 au 18 juin 1994 相似文献
- | an epidemiologic study of the predisposing factors of these fractures, |
- | to define a protocol of therapeutic indications. |
Présenté à la 38ème Réunion S.O.T.EST à Lons-le-Saunier du 17 au 18 juin 1994 相似文献