全文获取类型
收费全文 | 15455篇 |
免费 | 1452篇 |
国内免费 | 44篇 |
专业分类
耳鼻咽喉 | 136篇 |
儿科学 | 482篇 |
妇产科学 | 303篇 |
基础医学 | 1993篇 |
口腔科学 | 318篇 |
临床医学 | 1601篇 |
内科学 | 3389篇 |
皮肤病学 | 144篇 |
神经病学 | 1272篇 |
特种医学 | 466篇 |
外国民族医学 | 1篇 |
外科学 | 2689篇 |
综合类 | 424篇 |
一般理论 | 21篇 |
预防医学 | 1554篇 |
眼科学 | 339篇 |
药学 | 972篇 |
中国医学 | 23篇 |
肿瘤学 | 824篇 |
出版年
2023年 | 118篇 |
2022年 | 155篇 |
2021年 | 349篇 |
2020年 | 203篇 |
2019年 | 311篇 |
2018年 | 377篇 |
2017年 | 303篇 |
2016年 | 290篇 |
2015年 | 365篇 |
2014年 | 479篇 |
2013年 | 730篇 |
2012年 | 888篇 |
2011年 | 976篇 |
2010年 | 592篇 |
2009年 | 477篇 |
2008年 | 819篇 |
2007年 | 910篇 |
2006年 | 829篇 |
2005年 | 804篇 |
2004年 | 758篇 |
2003年 | 720篇 |
2002年 | 675篇 |
2001年 | 289篇 |
2000年 | 271篇 |
1999年 | 268篇 |
1998年 | 196篇 |
1997年 | 154篇 |
1996年 | 120篇 |
1995年 | 131篇 |
1994年 | 119篇 |
1993年 | 104篇 |
1992年 | 212篇 |
1991年 | 212篇 |
1990年 | 198篇 |
1989年 | 155篇 |
1988年 | 152篇 |
1987年 | 136篇 |
1986年 | 147篇 |
1985年 | 150篇 |
1984年 | 142篇 |
1983年 | 118篇 |
1982年 | 103篇 |
1981年 | 90篇 |
1980年 | 85篇 |
1979年 | 103篇 |
1978年 | 108篇 |
1977年 | 75篇 |
1975年 | 78篇 |
1973年 | 90篇 |
1972年 | 89篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
52.
53.
Cameron Platell John Mackay Brian Collopy Roy Fink Peter Ryan Rodney Woods 《ANZ journal of surgery》1995,65(8):570-575
This study reviewed a series of patients with Crohn's disease managed by surgeons of the Department of Colon and Rectal Surgery, St Vincent's Hospital, Melbourne, since 1978. There were 306 patients: 171 males and 135 females. The mean age at diagnosis was 33.4 years (range 11–93). The distribution of the disease was small bowel 32.3%, small bowel and colon 26.5%, colon 39.9%, and anal disease alone 1.6%. A total of 416 abdominal operations were performed on 204 patients. The commonest indications for surgery were failed medical therapy (21.9%), small bowel obstruction (15.9%), enteric tistula (10.1%), and intra-abdominal abscess (10.1%). The most frequently performed procedures were ileocolic resection with anastomosis (28.8%), small bowel resection (9.4%), and total colectomy and ileostomy (7.0%). Postoperative complications included anastomotic leaks in 4.0%. intra-abdominal abscess formation in 3.6%, and enterocutaneous fistulae developed in 6%. Three patients died during the review period. During follow up (mean 84.4). 30% of patients developed recurrence requiring further surgery at a mean of 72.7 months postoperatively. The most frequent site for a recurrence was the pre-anastomotic terminal ileum (61.7%). In conclusion. the majority of patients with Crohn's disease will require resectional surgery at some stage. This can be performed with a low mortality and morbidity, and a recurrence rate of around 5% per year. 相似文献
54.
The incidence of Type 1 diabetes is increasing worldwide, imposing enormous public health costs, as well as profoundly affecting individual quality of life. There is evidence that psychological problems are increased in children with diabetes and this morbidity is often associated with poor metabolic control. Specific risk factors for this dual morbidity are emerging from empirical studies. The next challenge is to identify effective interventions for use with children at risk for adverse mental and physical health outcomes. The intervention literature is reviewed. It is noted that most studies have used diabetes-specific, unstandardized interventions in groups of adolescents, with few interventions trialled with younger children. No study has targeted a specific psychological disorder such as behaviour problems or depression, both of which are known to be increased in children with diabetes and for which effective standardized interventions are available. Attention is drawn to methodological limitations in many of the studies conducted to date and suggestions made to reduce these in future interventions attempting to reduce the burden of illness in children with diabetes. 相似文献
55.
56.
Noel Cameron 《American journal of human biology》1992,4(2):223-234
Analyses of the economic, political, demographic, and health indicators of South Africa place it within the context of the developing nations of the world. In particular current urbanization and population growth rates will lead to an increase of the Black urban population from 6.5 million in 1985 to over 20 million by the year 2000. Such dramatic social change will place major stress on the health of urban children. Few studies are available, however, that may be used to monitor the growth, and by implication the health, of rural children and thereby act as a baseline for the investigation of the effects of the urban environment. Research since 1985 on the growth and nutritional status of children has concentrated on longitudinal studies of rural children to form a basis for comparison to their urban counterparts. The results of these rural studies demonstrate growth patterns characteristic of children living in developing countries with some degree of variation, particularly with regard to weight and subcutaneous fat, between different rural groups. Rural children have a superior growth status in comparison to “average” urban children but are inferior to “well-off” urban children. The urban environment thus favors those children with adequate socioeconomic support but may be disadvantageous to children from “average” backgrounds. Interpretation of the effects of the rural environment will be greatly enhanced with information relating to nutritional intake and morbidity. 相似文献
57.
Low dose preoperative radiotherapy for carcinoma of the oesophagus: results of a randomized clinical trial. 总被引:9,自引:0,他引:9
S J Arnott W Duncan G R Kerr P R Walbaum E Cameron W J Jack W J Mackillop 《Radiotherapy and oncology》1992,24(2):108-113
One-hundred-and-seventy-six patients with potentially operable squamous cell carcinoma or adenocarcinoma of the middle or lower thirds of the oesophagus were randomly assigned to preoperative radiotherapy or surgery alone. Patients assigned to the radiotherapy arm received 20 Gy in 10 treatments over 2 weeks, using parallel opposed 4 MV beams. The preoperative radiotherapy was not associated with any significant acute morbidity or any increase in operative complications. The median survival of the overall group of 176 patients was 8 months, and the 5-year survival was 13%. There was no significant difference in the survival of the 90 patients who received preoperative radiotherapy and the 86 who were managed by surgery alone. Proportional hazards analysis identified lymph node involvement, high tumour grade and male sex as significant adverse prognostic features, but the treatment option assigned had no prognostic significance. It was concluded that low dose preoperative radiotherapy offered no advantage over surgery alone. 相似文献
58.
59.
R M Leach C H Twort I R Cameron J P Ward 《Clinical science (London, England : 1979)》1992,82(1):55-62
1. The mechanical and pharmacological properties of small pulmonary arteries (100-300 microns normalized lumen diameter) were directly compared with those of the left main pulmonary artery (1-2 mm) from the rat. The active and passive length-tension characteristics and responses to a variety of agonists and antagonists were dependent on arterial diameter. 2. Maximum contractile function was obtained in both groups of vessels when stretched so as to give an equivalent transmural pressure of 30 mmHg. This is substantially lower than that found for systemic vessels, and reflects the normal low pulmonary arterial pressure. 3. Noradrenaline was a powerful vasoconstrictor in large but not small pulmonary arteries (P less than 0.001). In contrast, bradykinin produced a significantly greater response in the small arteries (P less than 0.001). In comparison with large pulmonary arteries, small arteries were more sensitive to noradrenaline (P less than 0.05) and 5-hydroxytryptamine (P less than 0.001), less sensitive to endothelin-1 (P less than 0.001) and had the same sensitivity to prostaglandin F2 alpha. 4. The mechanism that maintains the low arterial tone of the pulmonary circulation is unknown, but it may involve the release of relaxing factors from the endothelium. In this preparation, basal resting tone could not be demonstrated in either large or small arteries. 5. Acetylcholine-induced relaxation of pre-contracted pulmonary arteries was reduced or absent in the small artery, despite histological evidence of an intact endothelium. In large arteries pre-contracted with prostaglandin F2 alpha, acetylcholine (100 mumol/l) caused 88.2% relaxation compared with 25.2% in the small artery.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献