全文获取类型
收费全文 | 187148篇 |
免费 | 12379篇 |
国内免费 | 5052篇 |
专业分类
耳鼻咽喉 | 2646篇 |
儿科学 | 2576篇 |
妇产科学 | 2203篇 |
基础医学 | 25836篇 |
口腔科学 | 4013篇 |
临床医学 | 18321篇 |
内科学 | 29487篇 |
皮肤病学 | 4568篇 |
神经病学 | 12608篇 |
特种医学 | 10092篇 |
外国民族医学 | 8篇 |
外科学 | 24582篇 |
综合类 | 14157篇 |
现状与发展 | 17篇 |
一般理论 | 30篇 |
预防医学 | 11782篇 |
眼科学 | 4275篇 |
药学 | 17613篇 |
57篇 | |
中国医学 | 5503篇 |
肿瘤学 | 14205篇 |
出版年
2024年 | 230篇 |
2023年 | 1505篇 |
2022年 | 4309篇 |
2021年 | 6663篇 |
2020年 | 3957篇 |
2019年 | 4423篇 |
2018年 | 5235篇 |
2017年 | 4661篇 |
2016年 | 5485篇 |
2015年 | 7901篇 |
2014年 | 9717篇 |
2013年 | 11133篇 |
2012年 | 16528篇 |
2011年 | 16291篇 |
2010年 | 10631篇 |
2009年 | 9186篇 |
2008年 | 11770篇 |
2007年 | 11244篇 |
2006年 | 10285篇 |
2005年 | 9176篇 |
2004年 | 7687篇 |
2003年 | 7044篇 |
2002年 | 6100篇 |
2001年 | 4718篇 |
2000年 | 3879篇 |
1999年 | 2801篇 |
1998年 | 1273篇 |
1997年 | 1048篇 |
1996年 | 787篇 |
1995年 | 663篇 |
1994年 | 563篇 |
1993年 | 435篇 |
1992年 | 843篇 |
1991年 | 797篇 |
1990年 | 705篇 |
1989年 | 611篇 |
1988年 | 510篇 |
1987年 | 508篇 |
1986年 | 368篇 |
1985年 | 398篇 |
1984年 | 273篇 |
1983年 | 205篇 |
1982年 | 145篇 |
1981年 | 176篇 |
1980年 | 135篇 |
1979年 | 229篇 |
1978年 | 170篇 |
1976年 | 134篇 |
1975年 | 127篇 |
1974年 | 146篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
J S Kim 《Stroke; a journal of cerebral circulation》1992,23(7):983-987
BACKGROUND: Although pure sensory stroke is a relatively common lacunar syndrome, the responsible lesions are often unidentified because of their small size. I reported 21 cases of pure sensory stroke in which the lesions could be identified by head computed tomography and/or magnetic resonance imaging and correlated the clinical findings with the radiological lesions. SUMMARY OF REPORT: Eleven patients had thalamic strokes. Lacunes confined to the posterolateral part of the thalamus were found in nine cases, and hemorrhages of relatively large size were found in two. Five patients showed a loss of all sensory modalities, but six with very small lacunes showed minor or restricted sensory changes. Seven patients with lacunes or hemorrhages in the lenticulocapsular region or corona radiata showed abnormalities of spinothalamic tract sensation. Two patients with a small lacune and a hemorrhage in the pontine tegmentum showed a selective sensory deficit of the medial lemniscal type. One patient with a small cortical infarct showed a cortical sensory loss that was preceded by cortical sensory transient ischemic attacks. CONCLUSIONS: Pure sensory stroke can occur with lesions in various areas of the somatosensory system. Hemisensory deficits of all modalities usually are associated with a relatively large lacune or hemorrhage in the lateral thalamus, whereas tract-specific or restricted sensory changes suggest very small strokes in the sensory pathway from the pons to the parietal cortex. 相似文献
92.
J B Sherman M A Alexander D Gomez M Kim P Marole 《Journal of community health nursing》1992,9(3):183-190
The purpose of this study was to implement and evaluate a program for obese school children. A pretest-posttest design was utilized. Data was collected related to weight status, skinfold measurements, self-esteem, and nutritional knowledge. A convenience sample of 26 children, in the fourth to sixth grades, completed this 9-week program. The results indicate that self-esteem increased significantly (p less than .001) between the pretest and posttest interval. Weight status and nutritional knowledge showed no improvement. Exercise was difficult to assess on self-report, therefore no conclusions were were drawn in relation to this variable. Future research will be directed toward refining this intervention program. 相似文献
93.
We present three unusual cases of molluscum contagiosum occurring in epidermal cysts. All of them are asymptomatic, elevated, oval nodules diagnosed clinically as epidermal inclusion cyst or prurigo nodularis. Histology showed true epidermal cysts containing molluscum bodies throughout the cyst wall and some type of laminated material within the cyst itself. The lesion, in all three cases developed in the pubic area of young adult men. 相似文献
94.
T M Kim H R Brown S H Lee C V Powell P Bethune N L Goller H T Tran J S Mackay 《Modern pathology》1992,5(3):348-352
A 9-yr-old girl developed delayed acute measles inclusion body encephalitis, which was different from subacute sclerosing panencephalitis (SSPE) in clinical course. Measles virus was demonstrated by electron microscopy, immunohistochemistry, and in situ hybridization. Contrary to the most previous reports, matrix (M) protein was present in the brain, cerebrospinal fluid, and serum and was demonstrated by Western blot analysis and in situ hybridization. The hybridization was performed by a nonradioactive digoxigenin method. 相似文献
95.
96.
Philip Harber Laura Pea Paul Hsu Elizabeth Billet Deborah Greer Katty Kim 《American journal of industrial medicine》1994,25(4):519-526
Back pain among nurses is a common problem. Prior studies of this problem have been based on cross-sectional or retrospective data. This 18-month prospective study involving nurses newly graduated from nursing school investigated personal, worksite, and training factors associated with future risk of back pain. Each nurse underwent a preliminary interview and periodic follow-ups to identify those with back injuries. Contingency tables and logistic regression analyses demonstrated that prior significant back pain episodes (evidenced by previous job changes because of back pain, frequent medication use, etc.) were associated with increased future risk. Training at nursing school or on the job did not have a protective effect. This pilot study therefore suggests factors useful in placement and counseling of new nurses and indicates the need for further implementation of mechanical lift assist device use. © 1994 Wiley-Liss, Inc. 相似文献
97.
98.
Victoria L Morgan Benoit M Dawant Yong Li David R Pickens 《Computerized medical imaging and graphics》2007,31(6):436-446
The objectives of this study were to use computer-generated phantoms containing real subject motion to: (1) compare the sensitivity of four commonly used fMRI software packages and (2) compare the sensitivity of three statistical analysis strategies with respect to motion correction. The results suggest that all four packages perform similarly in fMRI statistical analysis with SPM2 having slightly higher sensitivity. The most sensitive analysis technique was to perform motion correction and include the realignment parameters as regressors in the general linear model. This approach applies to all four packages examined and can be most beneficial when stimulus-correlated motion is present. 相似文献
99.
TNF alpha and Fas mediate tissue damage and functional outcome after traumatic brain injury in mice.
Daniela Bermpohl Zerong You Eng H Lo Hyung-Hwan Kim Michael J Whalen 《Journal of cerebral blood flow and metabolism》2007,27(11):1806-1818
Tumor necrosis factor-alpha (TNFalpha) and Fas are induced after traumatic brain injury (TBI); however, their functional roles are incompletely understood. Using controlled cortical impact (CCI) and mice deficient in TNFalpha, Fas, or both (TNFalpha/Fas-/-), we hypothesized that TNFalpha and Fas receptor mediate secondary TBI in a redundant manner. Compared with wild type (WT), TNFalpha/Fas-/- mice had improved motor performance from 1 to 4 days (P<0.05), improved spatial memory acquisition at 8 to 14 days (P<0.05), and decreased brain lesion size at 2 and 6 weeks after CCI (P<0.05). Protection in TNFalpha/Fas-/- mice from histopathological and motor deficits was reversed by reconstitution with recombinant TNFalpha before CCI, and TNFalpha-/- mice administered anti-Fas ligand antibodies had improved spatial memory acquisition versus similarly treated WT mice (P<0.05). Tumor necrosis factor-alpha/Fas-/- mice had decreased the numbers of cortical cells with plasmalemma damage at 6 h (P<0.05 versus WT), and reduced matrix metalloproteinase-9 activity in injured brain at 48 and 72 h after CCI. In immature mice subjected to CCI, genetic inhibition of TNFalpha and Fas conferred beneficial effects on histopathology and spatial memory acquisition in adulthood (both P<0.05 versus WT), suggesting that the beneficial effects of TNFalpha/Fas inhibition may be permanent. The data suggest that redundant signaling pathways initiated by TNFalpha and Fas play pivotal roles in the pathogenesis of TBI, and that biochemical mechanisms downstream of TNFalpha/Fas may be novel therapeutic targets to limit neurological sequelae in children and adults with severe TBI. 相似文献
100.
Throughout history, societies have developed their own codes of ethics, including those pertaining to the practice of medicine. In the United States, physicians have adopted a set of ethics based on religious values and historical teachings. We, as physicians, have been presented several codes of ethics, including the American Medical Association Code of Ethics and the American College of Radiology Code of Ethics. Over time, we have learned to appropriately apply these codes to our daily practice. With the advent of new technologies in imaging, we may lose sight as to the transfer of these principles to reflect current conditions. Recent history has shown a trend of new technology leading to potential misuse of this technology and further leading to stricter governmental regulations. It is the purpose of this review to give guidelines for dealing with new technologies, such as PET imaging, and we describe a radiologist's ethical responsibility in a doctor-patient relationship. A historical review of medical ethics will lead to discussions about various issues affecting radiologists and nuclear physicians. To be sure, not all ethical situations are black and white, and therefore there are many gray areas. The opinions expressed in this article are those of the authors and are based on extension of already established rules of ethical conduct. 相似文献