全文获取类型
收费全文 | 2353599篇 |
免费 | 184913篇 |
国内免费 | 5462篇 |
专业分类
耳鼻咽喉 | 31904篇 |
儿科学 | 78994篇 |
妇产科学 | 66732篇 |
基础医学 | 337450篇 |
口腔科学 | 68836篇 |
临床医学 | 211114篇 |
内科学 | 454262篇 |
皮肤病学 | 51615篇 |
神经病学 | 189526篇 |
特种医学 | 92546篇 |
外国民族医学 | 756篇 |
外科学 | 354230篇 |
综合类 | 60062篇 |
现状与发展 | 6篇 |
一般理论 | 894篇 |
预防医学 | 184319篇 |
眼科学 | 54459篇 |
药学 | 175300篇 |
24篇 | |
中国医学 | 5105篇 |
肿瘤学 | 125840篇 |
出版年
2018年 | 23305篇 |
2016年 | 20490篇 |
2015年 | 23613篇 |
2014年 | 32326篇 |
2013年 | 49106篇 |
2012年 | 65713篇 |
2011年 | 69591篇 |
2010年 | 41406篇 |
2009年 | 39222篇 |
2008年 | 65845篇 |
2007年 | 69643篇 |
2006年 | 70716篇 |
2005年 | 68406篇 |
2004年 | 67145篇 |
2003年 | 64482篇 |
2002年 | 62799篇 |
2001年 | 108246篇 |
2000年 | 111713篇 |
1999年 | 94430篇 |
1998年 | 26410篇 |
1997年 | 24066篇 |
1996年 | 23788篇 |
1995年 | 23206篇 |
1994年 | 21750篇 |
1993年 | 20418篇 |
1992年 | 77299篇 |
1991年 | 75361篇 |
1990年 | 74057篇 |
1989年 | 71408篇 |
1988年 | 65896篇 |
1987年 | 65493篇 |
1986年 | 61828篇 |
1985年 | 59800篇 |
1984年 | 44962篇 |
1983年 | 38483篇 |
1982年 | 22816篇 |
1981年 | 20497篇 |
1980年 | 19193篇 |
1979年 | 42575篇 |
1978年 | 29994篇 |
1977年 | 25330篇 |
1976年 | 23849篇 |
1975年 | 25085篇 |
1974年 | 30673篇 |
1973年 | 29559篇 |
1972年 | 27121篇 |
1971年 | 25569篇 |
1970年 | 23548篇 |
1969年 | 22055篇 |
1968年 | 20254篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
961.
We describe a case of pathologic jealousy (Othello syndrome) in a patient with Parkinson disease, which abated after discontinuing amantadine. We indicate that early recognition and treatment of the syndrome in this disease may avert physical violence. We also believe that our report further suggests a link between this specific behavioral disorder and dopaminergic activity. 相似文献
962.
K J Meador J L Thompson D W Loring A M Murro D W King B B Gallagher G P Lee J R Smith H F Flanigin 《Neurology》1991,41(6):869-872
Although there has been extensive examination of the behavioral and physiologic correlates of hippocampal theta activity in animals, the human literature consists of a single case study. We investigated the differential effects of four behavioral states on human hippocampal theta activity in 16 epilepsy surgery patients. Behavioral conditions included resting eyes closed (RC), resting eyes open (RO), eyes open with auditory word activation (AW), and eyes open with visuospatial activation (VS). Hippocampal theta activity decreased during both RO and VS compared to both RC and AW. There were reciprocal changes in delta activity. Comparisons of RO to VS and of RC to AW were nonsignificant. The results demonstrate state-specific changes in human hippocampal theta and are consistent with the animal literature that relates hippocampal theta to sensorimotor integration and forebrain volitional mechanisms. 相似文献
963.
Modification of a hand splint for a musician who had suffered an incomplete disruption of the left ring finger extensor tendon is described. This modification enabled the patient to receive the benefit of conservative treatment of this disruption while continuing his employment. The modification can be performed easily with the standard stack splint; the success of this method is described. 相似文献
964.
R Bulbulian 《Aviation, space, and environmental medicine》1986,57(7):709-711
The effect of physical training on +Gz tolerance is of vital interest in the aerospace community. The data on the effect of physical training on orthostatic tolerance or simulated air combat maneuvers is equivocal. The effects of aerobic and strength training programs is briefly reviewed. The data suggest a need for careful reinterpretation of research results in light of conflicting reports and methodological shortcomings. Aerobic training cannot be assumed to always be detrimental nor can strength training be assumed to be universally effective in improving +Gz tolerance. In selecting appropriate screening criteria and training regimens for aircraft personnel, it seems prudent to reinvestigate strength and endurance training effects on +Gz tolerance using multivariate research paradigms. Special attention should be directed to commonly accepted physiological principles which may vary under conditions of altered gravitation. 相似文献
965.
Oxybutynin versus propantheline in patients with multiple sclerosis and detrusor hyperreflexia 总被引:2,自引:0,他引:2
Hyperreflexia is the most common urological finding in patients with multiple sclerosis. A prospective randomized study was done to compare the effectiveness of 2 commonly used drugs, oxybutynin and propantheline. Of the 34 patients entered into the trial 19 were treated with oxybutynin and 15 with propantheline. The urological symptoms (frequency, nocturia, hesitancy, urgency and urge incontinence) were graded according to severity from 0 to 3. Patients with urinary infection were excluded. Urodynamic examination, consisting of cystometrography and electromyography, was performed in all patients before treatment. Both groups of patients had comparable neurological, urological and urodynamic status before treatment. In 4 patients (21 per cent) treated with oxybutynin and in 4 (27 per cent) treated with propantheline side effects were so severe that the treatment had to be discontinued. Symptomatic response to oxybutynin was good in 10 patients (67 per cent), fair in 2 (13 per cent) and poor in 3 (20 per cent). Propantheline produced good symptomatic results in 4 patients (36 per cent), fair in 1 (9 per cent) and poor in 6 (55 per cent). The mean increase in maximum cystometric capacity on cystometrography was significantly larger in the oxybutynin group than in the propantheline group (144 +/- 115 versus 35 +/- 101). Our results indicate that oxybutynin is more effective than propantheline in the treatment of detrusor hyperreflexia in patients with multiple sclerosis. 相似文献
966.
Increased production of peroxidation products associated with cardiac operations. Evidence for free radical generation 总被引:7,自引:0,他引:7
D Royston J S Fleming J B Desai S Westaby K M Taylor 《The Journal of thoracic and cardiovascular surgery》1986,91(5):759-766
We investigated the degree and time course of neutrophil sequestration into human lungs during cardiac operations. At the same time, measurement of the concentration of peroxidation products in the plasma was used as an index of oxidant free radical activity. The study was performed in two groups of patients. Group A (n = 11) had studies extending over the entire operative period and showed a highly significant sequestration of neutrophils into the lung, together with a highly significant (p less than 0.001) rise in peroxidation products from 2.8 +/- 0.12 nmol/ml(mean +/- standard error of the mean)before bypass to a peak of 5.05 +/- 0.13 nmol/ml at the end of bypass. As these changes occurred only during the time after release of the aortic cross-clamp, we investigated this period in more detail in a second group of patients (Group B, n = 7). Results from this group showed that significant release of peroxidation products occurred at the same time as pulmonary neutrophil sequestration. This study has produced evidence of increased oxidant activity in the lung associated with cardiac operations. Nevertheless, it is not known whether the neutrophils sequestered into the lung alone induced the increased activity. Similarly, whether neutrophil-derived oxidant species are the sole cause of lung tissue injury remains unproved. 相似文献
967.
19 polygraphic sleep recordings from 12 patients with Pick's Disease, including four histologically proved cases, were compared to those of an age-matched control group. Symptoms had been present for a mean 8 years, the patients being aged 59 to 78 (mean 70.5 years). All sleep stages could be identified. Total sleep time was reduced and the number of awakenings was sharply increased. High proportion of stage 1 contrasted with the reduction in the other sleep stages with disappearance of stage 4 in advanced cases. REM Sleep was identified in all recordings, although reduced as a function of the length of the illness; its production as a function of total sleep time was not different from that of the control. REM Sleep appeared often fragmented and with a remarkably short latency, reminiscent of that observed in severely depressed patients. 相似文献
968.
969.
Is vasoactive intestinal polypeptide the principal transmitter involved in human penile erection? 总被引:5,自引:0,他引:5
Previous work from this laboratory reported on the effects of several autacoids and other agents on strips of human corpus cavernosum (cc) muscle. These investigations indicated the presence in the cc muscle of a) atropine-sensitive cholinoceptors, b) alpha- and beta-adrenoceptors and c) a non-adrenergic non-cholinergic mechanism. Several recent publications have presented evidence in support of the possibility that vasoactive intestinal polypeptide (VIP) is an important, or the chief, transmitter in human penile erection. This paper describes the actions of VIP and other compounds on the cc muscle and the effect of intracavernous injection of VIP in volunteers. Among the agents tested, VIP was the most potent relaxant of the cc muscle. This effect, which was seen at a dose as low as 0.03 nM, was suppressed by VIP antiserum. The response of the isolated penile vasculature to VIP was similar. VIP antiserum had no effect on the relaxation of the cc muscle produced by field stimulation. In five of the seven subjects given intracavernous VIP (1.0 micrograms.) some degree of penile enlargement was evident, but none had an erection. It is suggested that local release of VIP, withdrawal of the alpha-adrenoceptor mediated tonic supply to the penis and the activation of the latter's beta-adrenoceptors are all probably involved in penile erection in man. 相似文献
970.