全文获取类型
收费全文 | 5311篇 |
免费 | 505篇 |
国内免费 | 10篇 |
专业分类
耳鼻咽喉 | 17篇 |
儿科学 | 203篇 |
妇产科学 | 115篇 |
基础医学 | 730篇 |
口腔科学 | 70篇 |
临床医学 | 615篇 |
内科学 | 1109篇 |
皮肤病学 | 39篇 |
神经病学 | 544篇 |
特种医学 | 154篇 |
外科学 | 767篇 |
综合类 | 82篇 |
一般理论 | 1篇 |
预防医学 | 512篇 |
眼科学 | 364篇 |
药学 | 338篇 |
中国医学 | 1篇 |
肿瘤学 | 165篇 |
出版年
2022年 | 32篇 |
2021年 | 61篇 |
2020年 | 42篇 |
2019年 | 81篇 |
2018年 | 82篇 |
2017年 | 58篇 |
2016年 | 61篇 |
2015年 | 84篇 |
2014年 | 117篇 |
2013年 | 193篇 |
2012年 | 281篇 |
2011年 | 302篇 |
2010年 | 165篇 |
2009年 | 153篇 |
2008年 | 279篇 |
2007年 | 318篇 |
2006年 | 305篇 |
2005年 | 330篇 |
2004年 | 308篇 |
2003年 | 315篇 |
2002年 | 254篇 |
2001年 | 129篇 |
2000年 | 125篇 |
1999年 | 114篇 |
1998年 | 84篇 |
1997年 | 52篇 |
1996年 | 43篇 |
1995年 | 61篇 |
1994年 | 48篇 |
1993年 | 43篇 |
1992年 | 86篇 |
1991年 | 80篇 |
1990年 | 58篇 |
1989年 | 69篇 |
1988年 | 78篇 |
1987年 | 83篇 |
1986年 | 58篇 |
1985年 | 76篇 |
1984年 | 36篇 |
1983年 | 44篇 |
1982年 | 29篇 |
1979年 | 42篇 |
1978年 | 51篇 |
1977年 | 43篇 |
1976年 | 31篇 |
1975年 | 40篇 |
1974年 | 40篇 |
1973年 | 38篇 |
1972年 | 35篇 |
1971年 | 31篇 |
排序方式: 共有5826条查询结果,搜索用时 171 毫秒
11.
J P Dick 《Journal of the Royal Society of Medicine》1992,85(9):517-518
12.
E. Andrs G. Kaltenbach E. Noel M. Noblet‐Dick A.‐E. Perrin T. Vogel J.‐L. Schlienger M. Berthel J. F. Blickl 《International journal of laboratory hematology》2003,25(3):161-166
Background: It has been suggested that oral cobalamin (vitamin B12) therapy may be an effective therapy for treating cobalamin deficiencies related to food‐cobalamin malabsorption. However, the duration of this treatment was not determined. Patients and method: In an open‐label, nonplacebo study, we studied 30 patients with established cobalamin deficiency related to food‐cobalamin malabsorption, who received between 250 and 1000 μg of oral crystalline cyanocobalamin per day for at least 1 month. Endpoints: Blood counts, serum cobalamin and homocysteine levels were determined at baseline and during the first month of treatment. Results: During the first month of treatment, 87% of the patients normalized their serum cobalamin levels; 100% increased their serum cobalamin levels (mean increase, +167 pg/dl; P < 0.001 compared with baseline); 100% had evidence of medullary regeneration; 100% corrected their initial macrocytosis; and 54% corrected their anemia. All patients had increased hemoglobin levels (mean increase, +0.6 g/dl) and reticulocyte counts (mean increase, +35 × 106/l) and decreased erythrocyte cell volume (mean decrease, 3 fl; all P < 0.05). Conclusion: Our findings suggest that crystalline cyanocobalamin, 250–1000 μg /day, given orally for 1 month, may be an effective treatment for cobalamin deficiencies not related to pernicious anemia. 相似文献
13.
Prof. Dr. W. Lorenz B. Stinner M. Rothmund D. Duda W. Dick H. Menke Th. Junginger 《European Surgery》1992,24(3):128-134
Zusammenfassung Probleml?sungsstrategien zu perioperativen Prophylaxema?nahmen umfassen mehr Studienarten als Tierexperimente und kontrollierte
klinische Studien. Dabei verhelfen Methoden der kognitiven Psychologie und künstlichen Intelligenz zu neuen Verfahren, um
kontroverse Standpunkte in der klinischen Versorgung zu formalisieren. Der Weg vom Tierexperiment zur klinischen Indikation,
mag mühevoll und beschwerlich sein, aber die Strategie hat sich bei der perioperativen Antihistaminikaprophylaxe als eine
neue Form der Prophylaxe schon bew?hrt. Gerade wurde im Refresher Course der ASA, der amerikanischen Gesellschaft für An?sthesie
und Intensivmedizin, diese Prophylaxe für alle US-An?sthesisten empfohlen.
Mit Unterstützung durch die Deutsche Forschungsgemeinschaft (Lo 199/16-2). 相似文献
14.
The concept of uniform reporting of data in resuscitation has demonstrated
its potential value in pre-hospital and in-hospital cardiac arrest in
adults, infants and children, in laboratory research, in disaster research
and, hopefully, also in trauma care and research.
相似文献
15.
J Graeme Houston Stephen J Gandy Wendy Milne John B C Dick Jill J F Belch Peter A Stonebridge 《Nephrology, dialysis, transplantation》2004,19(7):1786-1791
BACKGROUND: Spiral or helical arterial blood flow patterns have been widely observed in both animals and humans. The absence of spiral flow has been associated with carotid arterial disease. The aim of this study was to detect the presence of aortic spiral flow using magnetic resonance imaging (MRI) and to evaluate the relationship of the presence of spiral aortic flow with renal arterial disease and renal function in the follow-up of patients with suspected renal atheromatous disease. METHODS: Prospective study of 100 patients with suspected renal arterial disease and 44 patient controls. Using a 1.5 T MRI unit (Siemens Symphony), phase contrast flow quantification and three-dimensional contrast enhanced MR angiography of the abdominal aorta were performed. Renal arterial stenoses (RAS) were classified minimal, moderate or severe. Renal function was followed at 3 months before and 6 months after MRI. RESULTS: Non-spiral flow was more prevalent in patients with more severe RAS. Renal impairment progressed significantly in severe RAS without spiral flow (P = 0.0065), but did not progress significantly in severe RAS with spiral flow (P = 0.12). In minimal or moderate RAS with or without spiral flow there was no significant progression (P = 0.16, 0.13, 0.47, 0.092, respectively). CONCLUSIONS: Aortic spiral blood flow can be assessed with MRI. Lack of aortic spiral blood flow in patients with severe RAS is associated with significant short-term renal function deterioration. Determination of blood flow patterns may be a useful indicator of renal impairment progression in patients with suspected renal artery stenosis. 相似文献
16.
Nicole Y. L. Oei Bernet M. Elzinga Oliver T. Wolf Michiel B. de Ruiter Jessica S. Damoiseaux Joost P. A. Kuijer Dick J. Veltman Philip Scheltens Serge A. R. B. Rombouts 《Brain imaging and behavior》2007,1(1-2):31-41
Glucocorticoids (GCs, cortisol in human) are associated with impairments in declarative memory retrieval. Brain regions hypothesized
to mediate these effects are the hippocampus and prefrontal cortex (PFC). Our aim was to use fMRI in localizing the effects
of GCs during declarative memory retrieval. Therefore, we tested memory retrieval in 21 young healthy males in a randomized
placebo-controlled crossover design. Participants encoded word lists containing neutral and emotional words 1 h prior to ingestion
of 20 mg hydrocortisone. Memory retrieval was tested using an old/new recognition paradigm in a rapid event-related design.
It was found that hydrocortisone decreased brain activity in both the hippocampus and PFC during successful retrieval of neutral
words. These observations are consistent with previous animal and human studies suggesting that glucocorticoids modulate both
hippocampal and prefrontal brain regions that are crucially involved in memory processing.
Electronic Supplementary Material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
17.
18.
F.?W. Ahnefeld J. Barth W. Dick A. Doenicke T. Fuchs H. Gervais H. Laubenthal H. L?llgen W. Lorenz H.?H. Mehrkens G.?H. Meuret H. M?llmann S. Piepenbrock B. Przybilla R. Ring W. Schmutzler G. Schultze-Werninghaus J. Schüttler H.?P. Schuster P. Sefrin M. Tryba J. Zander M. Zenz 《Der Anaesthesist》1994,43(4):211-222
19.
20.
Irregularly shaped small shadows on chest radiographs, dust exposure, and lung function in coalworkers' pneumoconiosis.
下载免费PDF全文
![点击此处可从《Occupational and environmental medicine》网站下载免费的PDF全文](/ch/ext_images/free.gif)
H P Collins J A Dick J G Bennett P O Pern M A Rickards D J Thomas J S Washington M Jacobsen 《Occupational and environmental medicine》1988,45(1):43-55
The predominant shapes of small opacities on the chest radiographs of 895 British coalminers have been studied. The aims were to determine whether irregular (as distinct from rounded) small opacities can be identified reproducibly, whether their occurrence is related to dust exposure, and whether they are associated with excess prevalence of respiratory symptoms or impairments of lung function. Six of the doctors responsible for regular radiological surveys of all British coalminers each classified all 895 radiographs twice and independently, using the International Labour Organisation's 1980 classification system. The majority view was that 39 films showed predominantly irregular small opacities, 131 showed predominantly small rounded opacities, and 587 showed no small opacities. Readers' opinions varied about the presence and shapes of shadows on the other 138 films. In general, consistency between readers (and within readers on repeated viewings) was satisfactory. The occurrence and profusion of irregular shadows were related significantly both to the men's ages and additionally to their cumulative exposure to respirable coalmine dust as determined from 15 years' dust monitoring close to where the miners had worked. For any given level of exposure, the average level of profusion of the small irregular opacities was less than the corresponding profusion of small rounded opacities. The prevalence rates of chronic cough and phlegm, and of breathlessness, were higher in those with small irregular opacities than in those with no small opacities (category 0/0), but the differences were not statistically significant after adjustment for other factors including smoking habits. The presence of irregular (but not rounded) small shadows was associated with an impairment in respiratory function averaging about 190 ml deficits in both FEV1 and FVC. These deficits were not explicable in terms of the men's ages, body sizes, and smoking habits and they were in addition to the lung function losses attributable to the miners' dust exposure as such. It is concluded that the presence and profusion of small irregular opacities should be taken into consideration when assessing the severity of coalworkers' simple pneumoconiosis. 相似文献