全文获取类型
收费全文 | 84645篇 |
免费 | 41786篇 |
国内免费 | 36篇 |
专业分类
耳鼻咽喉 | 1564篇 |
儿科学 | 4571篇 |
妇产科学 | 733篇 |
基础医学 | 16574篇 |
口腔科学 | 5243篇 |
临床医学 | 13710篇 |
内科学 | 24507篇 |
皮肤病学 | 7561篇 |
神经病学 | 13939篇 |
特种医学 | 2272篇 |
外科学 | 14409篇 |
综合类 | 136篇 |
一般理论 | 28篇 |
预防医学 | 5249篇 |
眼科学 | 1363篇 |
药学 | 6020篇 |
1篇 | |
中国医学 | 1034篇 |
肿瘤学 | 7553篇 |
出版年
2023年 | 109篇 |
2022年 | 124篇 |
2021年 | 1447篇 |
2020年 | 5159篇 |
2019年 | 10969篇 |
2018年 | 10281篇 |
2017年 | 11533篇 |
2016年 | 12210篇 |
2015年 | 12051篇 |
2014年 | 12067篇 |
2013年 | 12703篇 |
2012年 | 4595篇 |
2011年 | 4613篇 |
2010年 | 9205篇 |
2009年 | 5522篇 |
2008年 | 2469篇 |
2007年 | 1435篇 |
2006年 | 1399篇 |
2005年 | 1226篇 |
2004年 | 1143篇 |
2003年 | 1115篇 |
2002年 | 1212篇 |
2001年 | 921篇 |
2000年 | 817篇 |
1999年 | 386篇 |
1998年 | 128篇 |
1997年 | 85篇 |
1996年 | 89篇 |
1995年 | 94篇 |
1994年 | 68篇 |
1993年 | 64篇 |
1992年 | 99篇 |
1991年 | 102篇 |
1990年 | 96篇 |
1989年 | 68篇 |
1988年 | 67篇 |
1987年 | 73篇 |
1986年 | 62篇 |
1985年 | 69篇 |
1984年 | 52篇 |
1983年 | 55篇 |
1982年 | 50篇 |
1981年 | 39篇 |
1980年 | 30篇 |
1979年 | 40篇 |
1978年 | 34篇 |
1977年 | 42篇 |
1976年 | 27篇 |
1974年 | 30篇 |
1969年 | 25篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
72.
A Cabrera M Sánchez M A Izquierdo E Pastor J M Galdeano S Mintegui M A Lizarraga A Cuadrado M Ca?ada 《Revista espa?ola de cardiología》1992,45(10):637-644
Between 1985-1990 we studied by means of two-dimensional echocardiography 286 patients with isolated ventricular septal defect (VSD). A hundred and sixty three being male and 123 female, as a mean age of 5 +/- 3 months. Sixty two cases (22.3%) reveales associated anomalies and in other 63 (22.4%) there was in the evolution an aneurysm of the septum membranous. The projections used were apical 4-chamber, with or without aortic root; parasternal long-short axis of great arterias or at ventricular level; subcostal 4-chamber; right oblique outlet right outflow tract and left oblique outlet left and right outflow tracts. Patients with VSD smaller than 3 mm were excluded. Perimembranous defects, 189 cases (66%), were more frequent than muscular, 91 31.8%), and subarterial defects, 6 (2.1%). Only 19 (9 apical muscular, 6 perimembranous outlet and 4 perimembranous trabecular) were initially misclassified. The diameter of the VSD was large in subarterial (0.85 +/- 0.1 cm) and perimembranous outlet VSD (0.75 +/- 0.5 cm) compared with the rest. Each group of defects was more easily shown by one particular projection except trabecular muscular defect. In conclusion, we are able to state that two-dimensional echocardiography enables us to discover the size and situation of isolated ventricular defects. 相似文献
73.
74.
Antonio Z Gimeno‐García Adolfo Parra‐Blanco David Nicols‐Prez Cipriano Manzano‐Sanz Rafael Mndez‐Medina Enrique Quintero 《Digestive endoscopy》2006,18(2):144-146
Gastric mucormycosis involvement is a rare condition that usually occurs in inmunocompromised patients and frequently has a fatal outcome. We report the case of a 73‐year‐old woman admitted to the intensive care unit with severe bleeding after an acute pulmonary disease. Upper endoscopy disclosed wide and deep necrotic ulcers in the body and fundus of the stomach and greenish exudates with the antrum and the duodenum undamaged. Autopsy revealed an invasive mucormycosis and a severe atheromatosis. Several predisposing factors for mucormycosis infection have been reported until now. We postulate that ischemic gastritis could be a predisposing factor for colonization of zygomycete. 相似文献
75.
76.
Shaun E. Cowman Joseph R. Ferrari Matthew Liao‐Troth 《Journal of community psychology》2004,32(2):121-126
This study examined the relationship between psychological sense of community, social‐support networks, and care‐giver stress and satisfaction among firefighters. No significant gender differences were obtained, but zero‐order correlates demonstrated significant relationships among all four variables. In examining the mediating effects of social‐support satisfaction, partial mediation for psychological sense of community on care‐giver satisfaction was determined, as well as full mediation for psychological sense of community on care‐giver stress. Therefore, firefighters who are satisfied with the support they receive may experience less stress with their care giving than those who experience low levels of support satisfaction. Future studies should assess these relationships more extensively in other areas of civic responsibility among public‐service employees to delineate effective support avenues. © 2004 Wiley Periodicals, Inc. J Comm Psychol 32: 121–126, 2004. 相似文献
77.
K. K. Adamama‐Moraitou G. D. Brellou T. S. Rallis N. Zavros D. Pardali A. Dinopoulos I. Vlemmas 《Transboundary and Emerging Diseases》2006,53(2):81-84
A 3.5‐year‐old intact male American Pit Bull was presented because of urinary incontinence and dysuria. Constipation, followed by diarrhoea, ocular disturbances and finally regurgitation developed over the next 4 years. Autonomic dysfunction was evidenced by clinical presentation, as well as positive ophthalmic pilocarpine test and subnormal Schirmer tear test. Diagnosis, however, was established through histopathological and immunohistochemical examination. Lesions attributable to inflammatory degenerative neuropathy of the autonomic ganglia, which represents one of the various types of human autonomic failure, were detected. 相似文献
78.
T. W. Boesgaard S. I. Castella G. Andersen A. Albrechtsen T. Spars K. Borch‐Johnsen T. Jrgensen T. Hansen O. Pedersen 《Diabetic medicine》2007,24(7):702-706
AIMS: The glutamate decarboxylase gene (GAD2) encodes GAD65, an enzyme catalysing the production of the gamma-aminobutyric acid (GABA) which interacts with neuropeptide Y to stimulate food intake. It has been suggested that in pancreatic islets, GABA serves as a functional regulator of pancreatic hormone release. Conflicting results have been reported concerning the potential impact of GAD2 variation on estimates of energy metabolism. The aim of this study was to elucidate potential associations between the GAD2-243A-->G polymorphism and levels of body mass index (BMI) and estimates of glycaemia. METHODS: Using high-throughput chip-based matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, the GAD2-243A-->G (rs2236418) polymorphism was genotyped in a population-based sample (Inter99) of 5857 middle-aged, unrelated Danish White subjects. RESULTS: The G-allele was associated with modestly lower BMI (P = 0.01). In a case-control study of obesity, the G-allele frequency in 2582 participants with BMI < 25 kg/m2 was 19.5% (18.4-20.6) compared with 17.1% (15.5-18.8) in 968 participants having BMI > or = 30 kg/m2 (P = 0.03), odds ratio 0.9 (0.7-1.0). Of the 5857 subjects, GG carriers had lower fasting plasma glucose levels (mmol/l) [AA (n = 3859) 5.6 +/- 0.8; AG (n = 1792) 5.5 +/- 0.8; GG (n = 206) 5.5 +/- 0.8, P = 0.008] and lower 30-min oral glucose tolerance test (OGTT)-related plasma glucose levels (AA 8.7 +/- 1.9; AG 8.6 +/- 1.9; GG 8.6 +/- 2.0, P = 0.04), adjusted for sex, age and BMI. Analysing subjects who were both normoglycaemic and glucose tolerant (n = 4431) GG carriers still had lower fasting plasma glucose concentrations: AA (n = 2895) 5.3 +/- 0.4; AG (n = 1383) 5.3 +/- 0.4; GG (n = 153) 5.2 +/- 0.4 (P = 9.10(-5)). CONCLUSION: The present study suggests that the GAD2-243A-->G polymorphism in a population of middle-aged White people associates with a modest reduction in BMI and fasting and OGTT-related plasma glucose levels. 相似文献
79.
80.
The main goal of the present work was to longitudinally examine consequences of long‐term moderately elevated levels of stress for various health outcomes. To address this issue, data covering 10 years was used from the ongoing Swedish population‐based prospective Betula Study. Based on the ratings on a validated self‐reported stress scale, matched subsamples between 40 and 65 years of age were divided into a high (n = 137) and low (n = 211) stress group. The reported incidence of cardiovascular, diabetes, psychiatric, tumour and musculoskeletal diseases was assessed 5 and 10 years after baseline (baseline = 1993–1995) without contaminating effects of past health history. The incidence of diseases 5 years after baseline assessment showed no differences between the groups. After 10 years, there was a significantly higher incidence of psychiatric diseases, mainly depression in the high‐stress group as well as a significant effect for tumours, although the number of cases was low. Although moderately elevated stress level may have a possible impact on psychiatric diseases especially depression and some tumours, it seems that prolonged moderate stress does not appear to be harmful to other stress‐related diseases. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献