全文获取类型
收费全文 | 19125篇 |
免费 | 1290篇 |
国内免费 | 71篇 |
专业分类
耳鼻咽喉 | 342篇 |
儿科学 | 517篇 |
妇产科学 | 339篇 |
基础医学 | 2254篇 |
口腔科学 | 269篇 |
临床医学 | 1922篇 |
内科学 | 4263篇 |
皮肤病学 | 479篇 |
神经病学 | 1704篇 |
特种医学 | 687篇 |
外科学 | 2819篇 |
综合类 | 242篇 |
现状与发展 | 1篇 |
一般理论 | 26篇 |
预防医学 | 1742篇 |
眼科学 | 508篇 |
药学 | 1236篇 |
中国医学 | 23篇 |
肿瘤学 | 1113篇 |
出版年
2023年 | 95篇 |
2022年 | 153篇 |
2021年 | 441篇 |
2020年 | 272篇 |
2019年 | 409篇 |
2018年 | 523篇 |
2017年 | 358篇 |
2016年 | 421篇 |
2015年 | 458篇 |
2014年 | 675篇 |
2013年 | 946篇 |
2012年 | 1354篇 |
2011年 | 1436篇 |
2010年 | 781篇 |
2009年 | 746篇 |
2008年 | 1206篇 |
2007年 | 1308篇 |
2006年 | 1258篇 |
2005年 | 1235篇 |
2004年 | 1250篇 |
2003年 | 1077篇 |
2002年 | 956篇 |
2001年 | 179篇 |
2000年 | 154篇 |
1999年 | 190篇 |
1998年 | 239篇 |
1997年 | 161篇 |
1996年 | 138篇 |
1995年 | 142篇 |
1994年 | 126篇 |
1993年 | 106篇 |
1992年 | 122篇 |
1991年 | 94篇 |
1990年 | 77篇 |
1989年 | 99篇 |
1988年 | 75篇 |
1987年 | 87篇 |
1986年 | 83篇 |
1985年 | 79篇 |
1984年 | 94篇 |
1983年 | 67篇 |
1982年 | 85篇 |
1981年 | 98篇 |
1980年 | 75篇 |
1979年 | 70篇 |
1978年 | 54篇 |
1977年 | 65篇 |
1976年 | 41篇 |
1975年 | 40篇 |
1972年 | 36篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
OBJECTIVE: To determine clinical utility of fine needle aspiration (FNA) in parotid neoplasia. STUDY DESIGN AND SETTING: Retrospective cohort study. METHODS: FNA and final pathology data were reviewed for patients who underwent parotidectomy for malignancy. Surgical outcomes were compared between patients with malignant cytology versus nonmalignant/nondiagnostic cytology. RESULTS: Twenty-seven of 33 primary malignant parotid lesions underwent FNA. Seventeen (63.0%) patients were diagnosed with cancer on FNA. The remaining 16 patients did not undergo FNA (n = 6), had a nondiagnostic FNA specimen (n = 5), or were incorrectly diagnosed with a benign lesion (n = 5). Patients who went on to parotidectomy with intent to treat malignancy based on FNA had significantly higher rates of upfront neck dissections (47.1% vs 12.5%, P = 0.036) as well as clear pathological margins (70.6% vs 31.3%, P = 0.027) vs those with nonmalignant FNA diagnoses. CONCLUSIONS: Preoperative FNA diagnosis of malignancy improves surgical treatment of parotid cancer. SIGNIFICANCE: FNA in the evaluation of parotid masses should strongly be considered. 相似文献
102.
103.
104.
G Schneiderman 《Revue canadienne de psychiatrie》1986,31(7):662-664
The will is an instrument of generational transfer and change. In addition to the realistic decision making processes that go into the writing of a will, family dynamics play a role in this deliveration. This paper will describe a family where a surviving parent changed her will since she claimed that two of her three children were not showing her adequate love and respect. In brief family therapy and with legal support, the will was changed to its original form, dividing the estate equally. No changes were facilitated in family atmosphere or style. Several months later her eldest son's child was referred for treatment because of a behaviour problem at school and this family entered into family treatment. The family had to deal with the emotional disengagement of the grandmother. In addition, her oldest son's sadness, disappointment in his mother's behaviour, which was reflected in the grandson's symptomatology were worked through as well as structural changes to help build an organized family with a tradition based on integrity, trust, and respect. Family dynamics and changes in wills will be discussed. 相似文献
105.
An ELISA-based method for measurement of food-specific IgE antibody in mouse serum: an alternative to the passive cutaneous anaphylaxis assay 总被引:1,自引:0,他引:1
Birmingham N Payankaulam S Thanesvorakul S Stefura B HayGlass K Gangur V 《Journal of immunological methods》2003,275(1-2):89-98
Passive cutaneous anaphylaxis (PCA) assay has been a gold standard method to measure allergen-specific IgE antibody (ASIgE Ab) levels in allergy mouse models. Many factors including stringent guidelines for laboratory animal use make PCA a difficult choice. Therefore, alternative methods are needed that can be readily applied for measurement of specific IgE antibody levels in mouse serum. Herein we describe a novel ELISA-based method that is more sensitive in comparison to PCA, IgE isotype-specific (because it has little cross-reactivity with IgG1 or IgG2a isotype) and highly reproducible (<10% inter- or intra-assay variation). Furthermore, we demonstrate the utility of this assay to measure specific IgE Ab against a variety of food extracts including chicken egg, peanut, almond, filbert/hazelnut and sweet potato. These findings are of particular interest to those who are seeking (i) to measure food-extract-specific IgE antibody in animal models and (ii) an alternative to the animal-based PCA method to measure mouse IgE antibodies. 相似文献
106.
Analysis of the coxsackievirus B-adenovirus receptor gene in patients with myocarditis or dilated cardiomyopathy 总被引:1,自引:0,他引:1
Bowles NE Javier Fuentes-Garcia F Makar KA Li H Gibson J Soto F Schwimmbeck PL Schultheiss HP Pauschinger M 《Molecular genetics and metabolism》2002,77(3):257-259
Myocarditis and dilated cardiomyopathy (DCM) are common causes of morbidity and mortality in children and adults, most commonly due to infection with coxsackievirus B or adenovirus. Increased expression of the common human coxsackievirus B-adenovirus receptor (CAR) has been reported in patients with DCM. We investigated the CAR gene in patients with acquired or familial myocarditis/DCM for mutations/polymorphisms. Several polymorphisms or intronic substitutions, distant from the intron-exon boundaries, were identified but no mutations. Based upon these data it appears that CAR gene mutations are not a major host determinant in the development of myocarditis and DCM. 相似文献
107.
108.
109.
Cell-free translation of avian erythroblastosis virus RNA yields two specific and distinct proteins with molecular weights of 75,000 and 40,000 总被引:13,自引:0,他引:13
Avian erythroblastosis virus (AEV) 28 S virion RNA was translated in vitro in cell-free reticulocyte lysates. Two AEV-specific proteins, one of 75,000 (p75) the other of 40,000 (p40) molecular weight, were detected. p75 is a fusion protein containing gag-specific and AEV-specific peptides. It appears to be translated from the 5′-end of the 28 S AEV RNA and is indistinguishable from the p75 detected in AEV-transformed cells (Hayman et al., 1979). p40 does not share sequences with any viral structural protein. It also contains peptides distinct from those of p75, but one of the five identifiable p40 peptides comigrates with one of the p75 peptides. p40 is translated from a 20 S RNA which contains the 3′-half of the AEV-specific sequences of the genome. These two proteins account for all of the coding capacity of the AEV-specific gene sequences in the 28 S AEV RNA and are candidates for leukemia-specific transforming proteins. 相似文献
110.
Erik R Svendsen Karin B Yeatts David Peden Susan Orton Neil E Alexis John Creason Ronald Williams Lucas Neas 《Annals of allergy, asthma & immunology》2007,99(3):244-253
BACKGROUND: Identifying baseline inflammatory biomarkers that predict susceptibility to size-specific particulate matter (PM) independent of gaseous pollutants could help us better identify asthmatic subpopulations at increased risk for the adverse health effects of PM. OBJECTIVE: To evaluate whether the association between lung function and exposure to ambient levels of PM less than 2.5 microm in diameter (PM2.5) (fine) and 10 to 2.5 microm in diameter (PM(10-2.5)) (coarse) in children with persistent asthma differed across baseline measures of inflammation and innate immune activation. METHODS: We performed a panel study on a local population of 16 children with persistent asthma and evaluated daily pulmonary function (percentage of predicted peak expiratory flow and forced expiratory volume in 1 second) while concurrently measuring daily PM2.5 and PM(10-2.5) exposure from a central site in Chapel Hill, North Carolina. The children underwent a baseline medical evaluation that included assessment of several immunoinflammatory biomarkers in peripheral blood. RESULTS: Children without measurable CD14 expression on circulating neutrophils had significantly reduced pulmonary function (forced expiratory volume in 1 second and peak expiratory flow) with each interquartile range (IQR) increase in PM2.5 (IQR = 8.5 microg/m3) and PM(10-2.5) (IQR = 4.1 microg/m3) concentration, unlike children with measurable CD14 expression (P < .001 for interaction). CONCLUSIONS: Asthmatic children with muted surface expression of CD14 on circulating neutrophils may have a decreased capacity to respond to bacterial components of PM. 相似文献