全文获取类型
收费全文 | 10123篇 |
免费 | 461篇 |
国内免费 | 30篇 |
专业分类
耳鼻咽喉 | 154篇 |
儿科学 | 143篇 |
妇产科学 | 112篇 |
基础医学 | 1006篇 |
口腔科学 | 327篇 |
临床医学 | 582篇 |
内科学 | 2271篇 |
皮肤病学 | 350篇 |
神经病学 | 832篇 |
特种医学 | 408篇 |
外科学 | 1571篇 |
综合类 | 40篇 |
一般理论 | 1篇 |
预防医学 | 366篇 |
眼科学 | 135篇 |
药学 | 903篇 |
中国医学 | 11篇 |
肿瘤学 | 1402篇 |
出版年
2023年 | 62篇 |
2022年 | 112篇 |
2021年 | 170篇 |
2020年 | 109篇 |
2019年 | 146篇 |
2018年 | 193篇 |
2017年 | 162篇 |
2016年 | 162篇 |
2015年 | 176篇 |
2014年 | 233篇 |
2013年 | 255篇 |
2012年 | 425篇 |
2011年 | 483篇 |
2010年 | 266篇 |
2009年 | 212篇 |
2008年 | 413篇 |
2007年 | 423篇 |
2006年 | 445篇 |
2005年 | 449篇 |
2004年 | 427篇 |
2003年 | 384篇 |
2002年 | 400篇 |
2001年 | 408篇 |
2000年 | 401篇 |
1999年 | 382篇 |
1998年 | 129篇 |
1997年 | 97篇 |
1996年 | 95篇 |
1995年 | 81篇 |
1994年 | 73篇 |
1993年 | 57篇 |
1992年 | 255篇 |
1991年 | 244篇 |
1990年 | 248篇 |
1989年 | 243篇 |
1988年 | 214篇 |
1987年 | 203篇 |
1986年 | 164篇 |
1985年 | 178篇 |
1984年 | 126篇 |
1983年 | 107篇 |
1982年 | 45篇 |
1979年 | 87篇 |
1978年 | 57篇 |
1977年 | 54篇 |
1974年 | 53篇 |
1971年 | 49篇 |
1969年 | 46篇 |
1967年 | 46篇 |
1966年 | 43篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
141.
T Okamura R Suzuki Y Nakagawa A Terao S Sato A Kitamura Y Naito H Imano Y Tamura M Iida Y Komachi 《[Nihon kōshū eisei zasshi] Japanese journal of public health》1999,46(8):616-623
Since 1969, community-based stroke prevention programs have been conducted in N town, Kochi prefecture. To clarify factors related to participation in medical checkups including social networks, a cross-sectional questionnaire survey was performed on 6,704 residents aged 40 and over in N town in 1996. 1. Location of the workplace, types of medical insurance and interest in health were significantly associated with participation in medical checkups. 2. Participation in medical examinations provided at the workplace was significantly, inversely related with participation rates in community checkups in the group aged 40 to 59 years. 3. Low independence level in daily activities was inversely associated with participation rates for medical checkups in groups aged 60 years and older. 4. Visiting medical facilities was inversely associated with the participation rate for medical checkups in female groups. 5. The group with the highest social networks score (5 points) had the highest participation rate for medical checkups. After adjusting for other participation related factors, social networks scores had a significantly positive association with the participation rate for medical checkups provided by the Health Services for the Elderly Act. 相似文献
142.
T Tanaka N Kato T Doi K Ichikawa S Nakagawa K Miyasaka Y Takeda T Kitajima S Oda 《[Nihon kōshū eisei zasshi] Japanese journal of public health》1999,46(5):364-372
PURPOSE: We examined the child-rearing environmental factors that affect the occurrence of sudden infant death syndrome (SIDS) by using a nation-wide survey. METHOD: Infants who died due to SIDS between January 1996 and June 1997 in Japan were identified from death certificates. Controls of the same sex, birthplace, and birth months as the corresponding SIDS were chosen from birth certificates. Interviews of both cases and controls were undergone in January and February 1998 by public health nurses. RESULTS: The following Child-rearing factors exhibited a significant relationship with the occurrence of SIDS: 1. Concerning the sleeping position, the prone position was associated with increased risk compared to the supine position, with an odds ratio of 3.02 (95% c.i. 2.07-4.65). 2. Regarding the feeding method, artificial feeding only demonstrated a higher risk than breast feeding only, with an odds ratio of 4.92 (95% c.i. 2.78-9.63). 3. With regard to smoking, infants with both parents who smoked exhibited a higher risk than infants where neither parents smoked, with an odds ratio of 3.50 (95% c.i. 1.74-8.32). 相似文献
143.
M Ishizaki Y Yamada Y Morikawa Y Noborisaka M Ishida K Miura H Nakagawa 《Occupational medicine (Oxford, England)》1999,49(3):177-182
As a marker of body fat distribution and therefore level of obesity, the waist-to-hip ratio (W:H) is a good indicator of coronary heart disease risk status. The present study investigated the association between occupational status and life-style factors, and W:H of middle-aged Japanese male (n = 2,550) and female (n = 1,283) workers in a metal-products factory. A higher W:H was observed in the management level males as compared with the other male workers and we suggest this was promoted by the sedentary aspect of their work, as well as their higher levels of alcohol consumption and lower levels of leisure-time physical activity. In contrast, a higher W:H was recorded in female labourers, whose work was typically less sedentary as compared with female managers. Life-style factors included in the study were not related to this observation. We conclude that other unmeasured psychosocial factors may be important in promoting higher W:H in female labourers. 相似文献
144.
J Suzuki H Ohguro N Oguri M Satoh S Kon K Kogawa T Nakagawa 《Japanese journal of ophthalmology》1999,43(3):155-161
PURPOSE: To identify mucosa-associated lymphoid tissue (MALT) type lymphoma in conjunctival infiltrates. METHODS: Clinical, histopathologic, immunophenotypic, and immunogenotypic studies were performed on 14 patients with conjunctival lymphoid infiltrates. Surgical biopsy specimens were subjected to histopathologic, immunohistochemical, and gene rearrangement analysis. RESULTS: Thirteen of the 14 patients (92.9%) met the diagnostic criteria for MALT lymphoma, and the remaining patient showed morphologic features of diffuse, small lymphocytic lymphoma. Genotypic analysis confirmed immunoglobulin heavy chain gene rearrangement in all of the 12 patients on whom the analysis was performed. Two patients with bilateral lesions exhibited identical immunoglobulin rearrangement patterns in each pair of lesions. All patients were alive at the last follow-up (mean: 39.9 months). Nine of the 14 patients were alive without disease, 4 had localized recurrences, and 1 had a residual tumor. CONCLUSIONS: These findings indicate that conjunctival lymphoid infiltrates usually have the features of MALT lymphoma with genotypic B lymphocytic monoclonality and a favorable prognosis. 相似文献
145.
PURPOSE: To evaluate pigmentation on the anterior chamber angle in patients with atopic dermatitis. METHODS: This study includes 61 patients suffering from atopic dermatitis who visited our hospital between 1991 and 1995. Gonioscopy, cycloscopy, and fundus examinations with a scleral depressor were performed on every patient during the initial visit, and were repeated every 6 months. Pigmentation on the anterior chamber angle was classified according to Scheie. RESULTS: The pigmentation on the anterior chamber angle at the initial visit was evaluated as grade 0 (15 eyes), grade 1 (81 eyes), grade 2 (21 eyes), and grade 3 (5 eyes). Retinal detachment was found in 9 eyes of the 26 eyes with grade 2 or 3 pigmentation, but in only one of the 96 eyes with grade 0 or 1. The pigmentation on the anterior chamber angle correlated significantly with the incidence of retinal detachment (P < .0001). Causative breaks were found in the peripheral retina or ciliary epithelium in all eyes. CONCLUSIONS: Moderate to dense pigmentation on the anterior chamber angle in patients with atopic dermatitis seems to be a sign of breaks in the retina or ciliary epithelium, and the fundus of these patients should be examined carefully for signs of retinal detachment. 相似文献
146.
An immunohistochemical and immunoelectron microscopic study of adhesion molecules in synovial pannus formation in rheumatoid arthritis 总被引:3,自引:0,他引:3
H. Ishikawa S. Hirata Y. Andoh H. Kubo N. Nakagawa Y. Nishibayashi K. Mizuno 《Rheumatology international》1996,16(2):53-60
To investigate the mechanism of synovial pannus formation in rheumatoid arthritis, immunohistochemical and immunoelectron microscopic studies with monoclonal antibodies against the adhesion molecules, CD54 (ICAM-1), CD 11a (LFA-1), CDw49a (VLA-1), CDw49b (VLA-2), CDw49c (VLA-3), Cdw49d (VLA-4) and CDw49e (VLA-5), were carried out to determine the pattern of distribution of these molecules at the rheumatoid synovial cartilage junction. Treatment with anti-ICAM-1 resulted in membrane staining of most of the macrophages and fibroblasts infiltrating the synovial tissue and bordering the pannus-cartilage junction, suggesting the possibility that ICAM-1 may function to facilitate the adhesion of synovial type A cells bearing ICAM-1 to type B cells of the pannus. ICAM-1-positive macrophages and fibroblasts were often found to be in contact with lymphoid cells, suggesting also that a cellular immune reaction occurs in the formation of the pannus. In addition, VLA-3, VLA-4 and, particularly, VLA-5 were the predominant1 integrins expressed by rheumatoid synovial pannus. Since these three integrins all function as fibronectin receptors, it is possible that the fibronectin-rich environment of the rheumatoid cartilage surface effectively traps pannus cells expressing high levels of these molecules. The VLA-5 molecule was found in a pericellular and interterritorial matrix distribution in the present study, strongly suggesting that a recepfor-ligand interaction between VLA-5 and cartilage matrix may occur at the early stage of pannus formation. Furthermore, an increase in1 integrin may be necessary for the growth of the pannus and also for the upregulation of the VLA molecules, leading secondarily to increased attachment. 相似文献
147.
148.
Application of Akaike's information criterion (AIC) in the evaluation of linear pharmacokinetic equations 总被引:13,自引:0,他引:13
Kiyoshi Yamaoka Terumichi Nakagawa Toyozo Uno 《Journal of pharmacokinetics and pharmacodynamics》1978,6(2):165-175
According to linear pharmacokinetics, the time course of plasma concentration of a drug, Cp,is expressed by a sum of exponential functions, Cp=
i=1
n
ai
.This article describes a statistical technique to estimate the number of exponential terms, n,for the time course of drug by the application of Akaike's information criterion (AIC). Plasma concentrations of ethoxybenzamide, sulfisoxazole, bishydroxycoumarin, and diazepam measured following bolus intravenous injection were used as clinical examples for this method. Selection of models is compared between the AIC method and an Ftest method at significance levels of 5% and 1%. 相似文献
149.
The effects of consecutive oral administration of morphine on the cyclic AMP synthesizing system and cyclic AMP dependent protein kinase activity in the cerebral cortex of mice were examined. The administration of morphine (2--4 weeks) induced an increase of the cyclic AMP formation by activating adenylate cyclase, whereas responses of the cyclic AMP synthesizing system to biogenic amines (norepinephrine, dopamine and histamine) added in vitro was found to be significantly attenuated in these animals. Cyclic AMP dependent protein kinase activity in the cerebral cortex was also increased following a consecutive oral administration of morphine. These changes in the activities of adenylate cyclase and protein kinase were found mainly in crude mitochondrial and/or synaptosomal fractions. Morphine induced decrease in the response of the cyclic AMP synthesizing system to biogenic amines was rapidly reversed, and a significant increase of the cyclic AMP formation in the presence of added norepinephrine compared with that found in morphinized animals was observed following the administration of levallorphan, a narcotic antagonist. On the other hand, the changes in adenylate cyclase and cyclic AMP dependent protein kinase activities were not affected significantly by levallorphan administration. These results suggest that alterations in activities of cyclic AMP synthesizing system and of cyclic AMP dependent protein kinase may be involved in processes of the formation of morphine dependence. Possible involvement of abrupt increments in the sensitivity of "norepinephrine receptor-adenylate cyclase" system and a subsequent increase in cerebral cyclic AMP is also suggested as a cause of morphine withdrawal syndrome. 相似文献
150.
A case of Schonlein-Henoch-purpura is presented. The immunofluorescent study of skin lesions of the patient showed granular deposits of IgA and C3 in the blood vessel walls perivascular deposits of plasminogen and diffuse localization of fibrin and fibrinogen in the upper dermis. Complement activation via the alternative pathway through IgA, C3 and plasminogen deposits was suggested. 相似文献