全文获取类型
收费全文 | 51029篇 |
免费 | 3619篇 |
国内免费 | 171篇 |
专业分类
耳鼻咽喉 | 537篇 |
儿科学 | 1207篇 |
妇产科学 | 717篇 |
基础医学 | 6683篇 |
口腔科学 | 970篇 |
临床医学 | 4780篇 |
内科学 | 10727篇 |
皮肤病学 | 661篇 |
神经病学 | 5651篇 |
特种医学 | 1990篇 |
外国民族医学 | 3篇 |
外科学 | 7444篇 |
综合类 | 988篇 |
一般理论 | 86篇 |
预防医学 | 4538篇 |
眼科学 | 1042篇 |
药学 | 3319篇 |
1篇 | |
中国医学 | 64篇 |
肿瘤学 | 3411篇 |
出版年
2023年 | 183篇 |
2022年 | 322篇 |
2021年 | 756篇 |
2020年 | 433篇 |
2019年 | 768篇 |
2018年 | 916篇 |
2017年 | 679篇 |
2016年 | 770篇 |
2015年 | 943篇 |
2014年 | 1339篇 |
2013年 | 2137篇 |
2012年 | 3184篇 |
2011年 | 3371篇 |
2010年 | 1828篇 |
2009年 | 1751篇 |
2008年 | 3134篇 |
2007年 | 3460篇 |
2006年 | 3462篇 |
2005年 | 3679篇 |
2004年 | 3277篇 |
2003年 | 3073篇 |
2002年 | 3077篇 |
2001年 | 565篇 |
2000年 | 477篇 |
1999年 | 592篇 |
1998年 | 659篇 |
1997年 | 638篇 |
1996年 | 545篇 |
1995年 | 531篇 |
1994年 | 455篇 |
1993年 | 449篇 |
1992年 | 390篇 |
1991年 | 385篇 |
1990年 | 373篇 |
1989年 | 355篇 |
1988年 | 352篇 |
1987年 | 328篇 |
1986年 | 316篇 |
1985年 | 314篇 |
1984年 | 380篇 |
1983年 | 386篇 |
1982年 | 424篇 |
1981年 | 420篇 |
1980年 | 373篇 |
1979年 | 218篇 |
1978年 | 232篇 |
1977年 | 186篇 |
1976年 | 184篇 |
1975年 | 142篇 |
1974年 | 177篇 |
排序方式: 共有10000条查询结果,搜索用时 10 毫秒
51.
P A Raymond 《Experimental eye research》1990,51(6):675-683
In the retina of teleost fish, cone horizontal cell axons penetrate the inner nuclear layer, where they enlarge into fusiform terminal swellings. The present study shows that horizontal cell axon terminals enlarge disproportionately during postembryonic growth of the retina in juvenile and adult goldfish: the relative volume of axon terminals increases almost 20-fold, while the volume of the entire retina increases only about fourfold during a 2-3-yr period. The enlarging axon terminals fill in the gaps created as the numerical density of nuclei in the inner nuclear layer falls. Horizontal cell axon terminals are thought to participate in cone-dominated visual pathways, although their precise role is unclear. The results of this study suggest that a comparison of horizontal cell function in small and large fish might help to resolve this issue. 相似文献
52.
J. Randolph Swartz Ira M. Lesser Kyle B. Boone Bruce L. Miller Ismael Mena 《International journal of geriatric psychiatry》1995,10(6):437-446
Global and regional cerebral blood flow (CBF) were evaluated with single photon emission computerized tomography (SPECT) utilizing both 133Xenon (133Xe) (47 subjects, 47–82 years old) and 99Tc-hexamethylpropyleneamine oxime (99Tc-HMPAO) (27 subjects, 47–80 years old). The 133Xe results showed: among total subjects, no age-related decline in global CBF, but a significant regional decline in the occipital lobe (p < 0.05); among men, significant age-related declines in global, frontal, temporal, occipital and right hemisphere CBF (all p < 0.05); among women, no age-related decline in global or regional CBF. The 99Tc-HMPAO results showed no age-related decline in either global or regional perfusion among total subjects, men or women. These results suggest that age-related global and regional (including frontal lobe) CBF declines do not occur in healthy control subjects after the age of 45 years. However, gender differences in age-related CBF changes warrant further study. 相似文献
53.
54.
Six of 175 Angus heifers died after ingesting excessive amounts of Durango root (Datisca glomerata). Animals had rumens full of Durango root, were extremely lethargic, and had diarrhea prior to death. The animals had nonspecific postmortem lesions. This case is discussed in light of previous findings from trials in which Durango root was experimentally fed to cattle. 相似文献
55.
56.
Kristinn Tomasson George Winokur Bruce Pfohl Richard Abrams 《European archives of psychiatry and clinical neuroscience》1992,242(1):57-58
Eur Arch Psychiatry Clin Neurosci: (1992) 241:307–313 相似文献
57.
An outbreak of Salmonella dublin infection in England and Wales associated with a soft unpasteurized cows' milk cheese. 总被引:2,自引:0,他引:2
H Maguire J Cowden M Jacob B Rowe D Roberts J Bruce E Mitchell 《Epidemiology and infection》1992,109(3):389-396
An outbreak of Salmonella dublin infection occurred in England and Wales in October to December 1989. Forty-two people were affected, mainly adults, and most lived in south-east England. Microbiological and epidemiological investigations implicated an imported Irish soft unpasteurized cows' milk cheese as the vehicle of infection. A case-control study showed a statistically significant association between infection and consumption of the suspect cheese (p = 0.001). Salmonella dublin was subsequently isolated from cheeses obtained from the manufacturer's premises. Initial control measures included the withdrawal of the cheese from retail sale and a Food Hazard Warning to Environmental Health Departments, as well as a press release, from the Department of Health. Subsequently, a decision was taken by the manufacturer to pasteurize milk used in the production of cheese for the UK market and importation of the cheese resumed in June 1990. 相似文献
58.
Martin E. Weinand Bruce Hermann Allen R. Wyler L. Philip Carter K. J. Oommen David Labiner Geoff Ahern Anne Herring 《Epilepsia》1994,35(5):1054-1059
Summary: We report a series of 8 patients with ictal déjà vu. Subdural strip electrocorticographic (ECoG) monitoring localized the ictal epileptogenic focus as follows: right (n = 6) and left (n = 2) mesiotemporal lobe. In all 8 patients, the left hemisphere was dominant for language function based on intracarotid amytal testing. In 6 right-handed patients, ictal déjà vu was associated with a right temporal lobe focus. However, in the 2 left-handed patients, the ictal focus was left temporal lobe. Although ictal déjà vu localizes the epileptic focus to temporal lobe, this experiential phenomenon appears to lateralize to the hemisphere nondominant for handedness. 相似文献
59.
60.
Raymond J. Gibbons 《Journal of nuclear cardiology》1994,1(5):S118-S130
Both radionuclide angiography and myocardial perfusion imaging provide important insights that determine the management of patients with stable coronary artery disease. Both nuclear cardiology procedures have clearly demonstrated use in the noninvasvie identification of severe (left main or three-vessel) coronary artery disease and the noninvasive assessment of prognosis and thereby determine which patients should be sent to coronary angiography. Both radionuclide angiography and myocardial perfusion imaging provide prognostic information that is independent of resting left ventricular function and coronary anatomy and thereby influence the decision regarding which patients should be sent to coronary revascularization. This review considers the evidence supporting the uses of these nuclear cardiology procedures and provides suggestions regarding their cost-effective application. 相似文献