全文获取类型
收费全文 | 8291篇 |
免费 | 943篇 |
国内免费 | 8篇 |
专业分类
耳鼻咽喉 | 81篇 |
儿科学 | 302篇 |
妇产科学 | 227篇 |
基础医学 | 1307篇 |
口腔科学 | 181篇 |
临床医学 | 979篇 |
内科学 | 1530篇 |
皮肤病学 | 101篇 |
神经病学 | 819篇 |
特种医学 | 364篇 |
外国民族医学 | 1篇 |
外科学 | 1005篇 |
综合类 | 184篇 |
一般理论 | 5篇 |
预防医学 | 830篇 |
眼科学 | 145篇 |
药学 | 719篇 |
中国医学 | 10篇 |
肿瘤学 | 452篇 |
出版年
2022年 | 59篇 |
2021年 | 131篇 |
2020年 | 82篇 |
2019年 | 134篇 |
2018年 | 139篇 |
2017年 | 120篇 |
2016年 | 104篇 |
2015年 | 121篇 |
2014年 | 178篇 |
2013年 | 251篇 |
2012年 | 361篇 |
2011年 | 400篇 |
2010年 | 199篇 |
2009年 | 153篇 |
2008年 | 323篇 |
2007年 | 358篇 |
2006年 | 369篇 |
2005年 | 367篇 |
2004年 | 332篇 |
2003年 | 315篇 |
2002年 | 294篇 |
2001年 | 268篇 |
2000年 | 267篇 |
1999年 | 254篇 |
1998年 | 131篇 |
1997年 | 110篇 |
1996年 | 93篇 |
1995年 | 76篇 |
1994年 | 84篇 |
1993年 | 84篇 |
1992年 | 221篇 |
1991年 | 207篇 |
1990年 | 224篇 |
1989年 | 191篇 |
1988年 | 164篇 |
1987年 | 170篇 |
1986年 | 140篇 |
1985年 | 138篇 |
1984年 | 120篇 |
1983年 | 115篇 |
1982年 | 61篇 |
1981年 | 61篇 |
1979年 | 105篇 |
1978年 | 82篇 |
1977年 | 73篇 |
1976年 | 94篇 |
1975年 | 78篇 |
1974年 | 77篇 |
1973年 | 82篇 |
1972年 | 82篇 |
排序方式: 共有9242条查询结果,搜索用时 31 毫秒
61.
The stability of bendrofluazide 1.25 mg in capsules was studied. The formulation is intended to provide a unit dose powder for administration by dispersing the contents in liquid. The capsules were prepared from ground bendrofluazide tablets 5 mg from two different manufacturers, diluted with lactose and packed manually by weight into hard gelatin capsule shells. The capsules were stored at ambient temperature exposed to light or 75% relative humidity, and at 45 or 60C. The ambient temperature and 60C conditions were studied for up to 1 year. Bendrofluazide was determined by a stability-indicating HPLC method. The capsule contents remained easy to disperse in liquid by the end of the study. The weight of contents which could be extracted from the capsules also remained satisfactory. A 7-month storage life at ambient temperature would be feasible, based on the lower 95% confidence limits of the time to 5% degradation. 相似文献
62.
B F O'Donnell D A Drachman H J Barnes K E Peterson J M Swearer R A Lew 《Journal of geriatric psychiatry and neurology》1992,5(1):45-52
Factors predicting the early institutionalization of demented patients were studied in 143 outpatients using univariate and multivariate life-table methods. Four types of factors were evaluated for prognostic value: severity of functional impairment, behavioral disorders, individual patient characteristics, and type of caregiver. After follow-up of 19 +/- 12 months, 51 patients had been institutionalized. Increased global severity of dementia, the presence of troublesome and disruptive behaviors, and incontinence increased the likelihood of institutionalization. The best predictors of institutionalization were paranoia, aggressive behavior, and incontinence. Neither individual patient characteristics (age, education, and gender) nor caregiver relationship to the patient (male spouse, female spouse, and male or female child) influenced institutionalization. Since troublesome behavioral disorders are potentially treatable aspects of dementia leading to institutionalization, their management should be a major focus of therapy in dementia. 相似文献
63.
64.
65.
Jacqueline Barnes 《Child and Adolescent Mental Health》1997,2(4):163-169
There is increasing interest in the influence of community characteristics on child development and family functioning. In order to address questions on community influence, it is important to be aware of the measures available and their strengths and limitations. Useful strategies have been developed within a number of disciplines, including sociology, social and community psychology, and criminology. Methods include summarising information from existing administrative databases and census data, conducting observations, and using survey instruments with residents. The most commonly used methods are reviewed and their psychometric properties described . 相似文献
66.
Leukotriene B4 (LTB4) and the protein kinase C activator, 4-beta-phorbol dibutyrate (PDBu), both induced a pronounced and concentration-dependent stimulation of hydrogen peroxide (H2O2) generation by purified guinea pig peritoneal eosinophils in the concentration range 1 nM-1 microM. The LTB4 response was inhibited competitively by the specific LTB4 receptor antagonist, U-75302, with a KB of 25 nM, while the concentration-response curves for both stimuli were shifted rightwards (3.8-fold and 2.8-fold for LTB4 and PDBu, respectively) by the competitive protein kinase C inhibitor, 1-O-hexadecyl-2-O-methylglycerol at a concentration of 300 microM. LTB4 appears, therefore, to induce respiratory burst in eosinophils via a receptor-mediated mechanism involving protein kinase C. 相似文献
67.
68.
In order to determine the frequency and natural history of benign extracerebral fluid collections, computed tomography reports from a period of 26 months at Oklahoma Children's Memorial Hospital were reviewed (total scans: 3,411). Bilateral frontal extracerebral fluid collections were found in 94 infants under 1 year of age. Eighty-two infants had computed tomography scans as part of the evaluation for macrocrania. Thirteen patients had the typical findings of benign extracerebral fluid collections but otherwise were completely asymptomatic. Longitudinal observation for up to 30 months failed to reveal any changes in neurologic status of these patients. Benign extracerebral fluid collections are a relatively common cause of macrocrania in infants. The presence of these fluid collections is not of immediate concern, providing that clinical evaluations fail to identify either neurologic or developmental abnormalities. 相似文献
69.
Loss of heterozygosity mutations of tumor suppressor genes in cytologically atypical areas in chronic lymphocytic thyroiditis 总被引:1,自引:0,他引:1
Hunt JL Baloch ZW Barnes L Swalsky PA Trusky CL Sesatomi E Finkelstein S LiVolsi VA 《Endocrine pathology》2002,13(4):321-330
The relationship between chronic lymphocytic thyroiditis (CLT) and papillary thyroid carcinoma (PTC) is a subject of controversy. Some investigators suggest a causal relationship, whereas others regard the two as only a coincidental occurrence. An additional complicating factor is the presence of atypical nuclei frequently found within lymphoid infiltrates in CLT, which resemble those in PTC. The finding of the RET-PTC translocations in CLT has been reported by two independent groups of investigators, suggesting that the areas of nuclear atypia in CLT are neoplastic rather than reactive. In the present study, we report additional molecular findings that support the hypothesis that the atypical nuclear changes in CLT may be preneoplastic or neoplastic. We microdissected small areas with atypical nuclei in glands with CLT and observed loss-of-heterozygosity mutations of tumor suppressor genes. These genetic mutations are evidence of clonal preneoplastic or neoplastic changes in the follicular cells of CLT. The clinical malignant potential of these minute foci is likely to be very small but remains to be determined. 相似文献
70.