全文获取类型
收费全文 | 22503篇 |
免费 | 1922篇 |
国内免费 | 44篇 |
专业分类
耳鼻咽喉 | 228篇 |
儿科学 | 802篇 |
妇产科学 | 524篇 |
基础医学 | 2869篇 |
口腔科学 | 388篇 |
临床医学 | 2618篇 |
内科学 | 4379篇 |
皮肤病学 | 298篇 |
神经病学 | 1798篇 |
特种医学 | 935篇 |
外国民族医学 | 1篇 |
外科学 | 2881篇 |
综合类 | 604篇 |
一般理论 | 11篇 |
预防医学 | 2323篇 |
眼科学 | 863篇 |
药学 | 1505篇 |
中国医学 | 20篇 |
肿瘤学 | 1422篇 |
出版年
2022年 | 141篇 |
2021年 | 381篇 |
2020年 | 217篇 |
2019年 | 388篇 |
2018年 | 451篇 |
2017年 | 336篇 |
2016年 | 356篇 |
2015年 | 450篇 |
2014年 | 595篇 |
2013年 | 823篇 |
2012年 | 1197篇 |
2011年 | 1234篇 |
2010年 | 688篇 |
2009年 | 691篇 |
2008年 | 1140篇 |
2007年 | 1201篇 |
2006年 | 1148篇 |
2005年 | 1066篇 |
2004年 | 1085篇 |
2003年 | 1014篇 |
2002年 | 975篇 |
2001年 | 549篇 |
2000年 | 580篇 |
1999年 | 528篇 |
1998年 | 272篇 |
1997年 | 247篇 |
1996年 | 212篇 |
1995年 | 218篇 |
1994年 | 213篇 |
1993年 | 208篇 |
1992年 | 404篇 |
1991年 | 421篇 |
1990年 | 393篇 |
1989年 | 385篇 |
1988年 | 335篇 |
1987年 | 319篇 |
1986年 | 327篇 |
1985年 | 318篇 |
1984年 | 247篇 |
1983年 | 195篇 |
1982年 | 157篇 |
1981年 | 136篇 |
1980年 | 142篇 |
1979年 | 181篇 |
1978年 | 146篇 |
1977年 | 145篇 |
1976年 | 122篇 |
1974年 | 134篇 |
1973年 | 137篇 |
1971年 | 118篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
52.
MRI of pancreatic gastrinomas. 总被引:1,自引:0,他引:1
D G Mitchell M Cruvella D J Eschelman M M Miettinen J J Vernick 《Journal of computer assisted tomography》1992,16(4):583-585
Pancreatic islet cell tumors are often small and multiple, and preoperative diagnosis can be difficult. In a woman with hypergastrinemia, angiography and CT each depicted a solitary lesion. Magnetic resonance images, acquired using fat suppression, fast spin echo, and contrast material injection, depicted seven separate lesions, which were surgically confirmed. 相似文献
53.
In a cohort of 919 patients with definite or classic rheumatoid arthritis followed prospectively since 1966, we identified 36 patients with Felty's syndrome (FS). Their clinical course was compared to that of 72 matched controls from the same cohort. Patients with FS had more extraarticular features and more infections than control patients. The presence of joint erosions, serial Lansbury indices, and death rates were similar in both groups. Cardiovascular disease was the commonest cause of death in both groups, accounting for 32% of all deaths. Sepsis accounted for 10% of deaths in the group with FS and 13% of deaths in the controls. 相似文献
54.
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
55.
Eric K. Outwater Katsuyoshi Ito Evan Siegelman C. Edwin Martin Manoj Bhatia Donald G. Mitchell 《Journal of magnetic resonance imaging : JMRI》1997,7(6):1033-1039
The purpose of this study is to describe a subset of atypical hepatic hemangiomas that enhance rapidly and diffusely and to determine whether heavily T2-weighted images could distinguish between atypically enhancing liver hemangiomas and hypervascular malignancies. A retrospective search of MR records identified seven patients with liver hemangiomas that demonstrated diffuse early enhancement and 23 patients with biopsy-proven malignant liver lesions that were hypervascular on dynamic gadolinium-enhanced MR images. Quantitative analysis of signal intensity measurements was performed on the T2-weighted images, heavily T2-weighted (TE < 140), and dynamic gadolinium-enhanced images. Blinded reader comparison of the T2-weighted images and gadolinium-enhanced images was performed. Hypervascular hemangiomas enhanced to a greater degree than hypervascular malignant liver lesions on the early phase gadolinium-enhanced images. Perilesional parenchymal enhancement was demonstrated in five cases of rapidly enhancing hemangiomas. Signal intensity and contrast-to-noise ratios on the heavily T2-weighted images of the hemangiomas were significantly greater than that of the hypervascular malignant lesions (P < .05). Hemangiomas were differentiated from the hypervascular malignant liver lesions with high accuracy (97–100%) by three blinded readers based on the T2-weighted images. A subset of hemangiomas have atypical rapid diffuse enhancement on dynamic gadolinium-enhanced images. These atypical hemangiomas can be distinguished from hypervascular malignant liver lesions on T2-weighted MR images. 相似文献
56.
57.
H W Pogrebniak M J Merino S M Hahn J B Mitchell H I Pass 《Surgery》1992,112(2):130-9; discussion 138-9
58.
59.
M. V. Agrez S. Senthiselvan D. A. Henry A. Mitchell J. M. Duggan 《ANZ journal of surgery》1992,62(5):338-343
A review of 174 consecutive patients admitted with a diagnosis of perforated peptic ulcer to eight Hunter Region hospitals during 1979–86 is presented. Among the female admissions, the proportion of patients > 70 years of age was twice that in males. One-third of all perforations were in females who accounted for two-thirds of all perforated gastric ulcers. Multivariate analysis revealed that perforations located in the stomach and older age were both significant independent variables adversely affecting outcome following surgery. In contrast, shock at presentation and delay in operating were not statistically significant independent risk factors. 相似文献
60.
The effect of oral premedication was investigated in a double-blind, randomised trial in 85 children undergoing tonsillectomy and/or adenoidectomy. Orally administered midazolam 0.5 mg.kg−1 given 30 min pre-operatively was compared with trimeprazine 2 mg.kg−1 given 90 min pre-operatively and a placebo preparation. Compliance, sedation and ease of induction were assessed as were the duration and quality of recovery. Following premedication with midazolam none of the patients was anxious, crying or distressed on leaving the ward, compared with 2/28 in the trimeprazine group and 5/28 in the placebo group (p =0.0007). More patients were calm and quiet on arrival in the anaesthetic room following midazolam than following trimeprazine, with both premedicant agents comparing favourably with placebo. There was no significant difference between the three groups in the time to recovery or the sedation score on discharge to the ward. Midazolam is a safe and effective oral premedicant for children. 相似文献