全文获取类型
收费全文 | 2622篇 |
免费 | 156篇 |
国内免费 | 6篇 |
专业分类
耳鼻咽喉 | 22篇 |
儿科学 | 75篇 |
妇产科学 | 45篇 |
基础医学 | 325篇 |
口腔科学 | 212篇 |
临床医学 | 137篇 |
内科学 | 536篇 |
皮肤病学 | 28篇 |
神经病学 | 202篇 |
特种医学 | 76篇 |
外科学 | 352篇 |
综合类 | 11篇 |
预防医学 | 243篇 |
眼科学 | 48篇 |
药学 | 152篇 |
中国医学 | 16篇 |
肿瘤学 | 304篇 |
出版年
2023年 | 19篇 |
2022年 | 39篇 |
2021年 | 69篇 |
2020年 | 44篇 |
2019年 | 66篇 |
2018年 | 82篇 |
2017年 | 52篇 |
2016年 | 64篇 |
2015年 | 75篇 |
2014年 | 97篇 |
2013年 | 125篇 |
2012年 | 177篇 |
2011年 | 187篇 |
2010年 | 105篇 |
2009年 | 93篇 |
2008年 | 134篇 |
2007年 | 154篇 |
2006年 | 147篇 |
2005年 | 136篇 |
2004年 | 96篇 |
2003年 | 102篇 |
2002年 | 109篇 |
2001年 | 74篇 |
2000年 | 50篇 |
1999年 | 58篇 |
1998年 | 12篇 |
1997年 | 18篇 |
1995年 | 12篇 |
1994年 | 13篇 |
1993年 | 15篇 |
1992年 | 30篇 |
1991年 | 40篇 |
1990年 | 38篇 |
1989年 | 19篇 |
1988年 | 20篇 |
1987年 | 13篇 |
1986年 | 14篇 |
1985年 | 18篇 |
1984年 | 16篇 |
1983年 | 12篇 |
1980年 | 7篇 |
1979年 | 11篇 |
1978年 | 8篇 |
1976年 | 8篇 |
1975年 | 8篇 |
1974年 | 7篇 |
1973年 | 12篇 |
1971年 | 9篇 |
1968年 | 10篇 |
1966年 | 6篇 |
排序方式: 共有2784条查询结果,搜索用时 0 毫秒
1.
Objective
The aim of this paper is to study the opportunity costs (OC) that are involved in being a caregiver and to compare them with the direct costs assumed by the State and the families. We evaluate direct cost (those that imply a payment-out-of-pocket) and indirect cost (those that imply a dedication in time). We hypothesized that costs increase with the severity of the dementia, with the educational level and active occupational situation of caregiver. They are greater if the caregiver is male, but if the patient and caregiver cohabit they are reduced.Method
778 surveys were analyzed. Data was collected using a questionnaire specifically designed for the purpose, with the collaboration of Alzheimer's Diseases Associations in Andalusia (Spain). For the indirect cost, we used the reveal preferences method. For the comparison between groups an ANOVA and a MANOVA was done.Results
The hypotheses were confirmed. The OC exponentially increases with severity. More than 55% of costs are assumed by families. Occupied people have higher educational level and incomes and contract more external support. Costs are significantly higher for male caregivers. Cohabiting reduces all kinds of costs.Conclusions
The relationship between educational level and employment situation lead to think that if these variables are greater more people will seek professional support. Cultural reasons still maintain women as main caregivers for all educational levels. The existence of these informal caregivers as the main care providers is a saving for the State, and a brake for the development of professional supply. 相似文献2.
3.
A. B. Soares P. R. Faria L. A. Magna M. E. P. Correa C. A. de Sousa O. P. Almeida M. L. Cintra 《Journal of oral pathology & medicine》2005,34(6):368-373
BACKGROUND: Graft-vs.-host disease (GVHD) is the major cause of morbidity and mortality in patients undergoing allogeneic Bone Marrow Transplantation (BMT). The aim of our study was to identify the most relevant histological features for diagnosis of chronic Graft-vs.-Host Disease (cGVHD) in oral mucosa and minor salivary glands of 25 patients, as well as to evaluate the immunophenotype of the inflammatory cells. METHODS: Sixteen patients that were submitted to allogeneic BMT but did not present cGVHD were selected as a control group. The sections were studied on H & E and CD68, CD45, CD4, CD8, CD20 staining. RESULTS: The most frequent histologic findings in oral mucosa at the day of diagnosis of cGVHD were: hydropic degeneration of the basal layer of the epithelium, apoptotic bodies, lymphocytic infiltration, and focal or total cleavage between the epithelial and connective tissue. In the labial salivary glands (LSG), lymphocytic infiltration, acinar loss and fibrosis were the main alterations. Cytotoxic CD8-T cells and macrophages were predominant both in the epithelium and connective tissue, as well as in minor salivary glands. CONCLUSIONS: Histological features were useful in the diagnosis of oral cGVHD. It is suggested that CD8-T cells and macrophages play important role in the pathogenesis of the disease. 相似文献
4.
5.
We have analyzed the cellular and humoral immunity to the mycobacterial 65 KDa heat shock protein (hsp65) in a group of Freund's Adjuvant-immunized rats with a limited susceptibility to Adjuvant arthritis. According to the arthritis indices during the period of study (35 days), two different groups of rats could be distinguished; a) autoimmune Adjuvant arthritic rats (AA), and b) Non-arthritic animals (NA), including both rats which did not display any disease symptoms and rats suffering mild transient inflammation. The cellular response to the immunizing agent (Mycobacterium tuberculosis) or the mitogen Concanavalin A was comparable between both groups of rats. However, we detected an impaired cellular response to the individual hsp65 antigen in the animals that did not develop the disease. On the contrary, the level of hsp65-specific antibodies was much higher in NA animals than in AA rats suggesting a protective role for the hsp65 specific antibodies. 相似文献
6.
Diet and chronic atrophic gastritis: a case-control study 总被引:2,自引:0,他引:2
E Fontham D Zavala P Correa E Rodriguez F Hunter W Haenszel S R Tannenbaum 《Journal of the National Cancer Institute》1986,76(4):621-627
A hospital-based case-control study of gastric cancer precursor lesions was conducted in a high-risk black population in southern Louisiana. Ninety-three subjects with biopsy-proved advanced chronic atrophic gastritis were compared to two control series: a gastroscopy clinic series and a general hospital-admission series. Dietary case-control differences indicated a protective effect associated with fruit and vegetable intake and with dietary vitamin C and a risk elevation associated with milk consumption. The protective effect associated with consumption of fruits, vegetables, and vitamin C is consistent with findings for gastric cancer and with the etiologic hypothesis of intragastric nitrosation. A twofold increased risk was associated with cigarette smoking. Gastric juice pH, NO3-, and NO2- were determined for subjects undergoing gastroscopy, and comparisons were made between this high-risk U.S. group and a Colombian population with a much greater magnitude of risk; the latter had higher NO3- and NO2- levels. An increase in pH was associated with increasing severity of gastric lesions. Levels of pH and NO2- concentration were significantly correlated (P less than .0005); however, in Louisiana the large difference in NO2- concentration associated with pH elevation is not associated with histopathologic severity. Divergent trends with severity of lesions for NO3- concentration were seen in the two populations. 相似文献
7.
P Correa 《Journal of the National Cancer Institute. Monographs》1992,(12):75-78
The relative strengths of the etiologic factors identified for gastric cancer are discussed. On the basis of available scientific data, it is recommended that dietary prevention of gastric cancer be based on attempts to reduce the ingestion of foods with a high content of salt and to increase the intake of fresh fruits and vegetables. Other identified etiologic factors offer promise and are being investigated but do not yet justify recommendation to the general public. 相似文献
8.
M Rugge Y H Shiao P Correa R Baffa F DiMario 《Cancer epidemiology, biomarkers & prevention》1992,1(7):551-554
Molecular abnormalities of the p53 gene in chromosome 17p may be among the most commonly observed in human cancer. Their role in gastric carcinogenesis is suggested by their frequent detection in invasive adenocarcinomas. To investigate the chronology with which these abnormalities appear in the gastric carcinogenesis process, the expression of p53 proteins was investigated in late stages of the process, namely dysplasia, and in superficial carcinomas. A polyclonal antibody, CM-1, against both wild-type and mutant proteins was applied to paraffin-embedded biopsy and gastrectomy specimens previously fixed in buffered formalin. Positive nuclear stain was obtained in 36.4% of 33 cases of gastric epithelial dysplasia, corresponding to 19% of mild, 27.3% of moderate, and 64.3% of severe dysplasias. Eight of 13 (61.5%) invasive carcinomas showed positive stain. The data indicate an increased incidence of p53 abnormalities in the late stages of gastric carcinogenesis. 相似文献
9.
10.