全文获取类型
收费全文 | 160689篇 |
免费 | 10906篇 |
国内免费 | 701篇 |
专业分类
耳鼻咽喉 | 1770篇 |
儿科学 | 4072篇 |
妇产科学 | 2642篇 |
基础医学 | 21154篇 |
口腔科学 | 3447篇 |
临床医学 | 15801篇 |
内科学 | 34107篇 |
皮肤病学 | 3314篇 |
神经病学 | 14665篇 |
特种医学 | 7355篇 |
外国民族医学 | 14篇 |
外科学 | 25306篇 |
综合类 | 2001篇 |
一般理论 | 109篇 |
预防医学 | 11893篇 |
眼科学 | 3324篇 |
药学 | 10216篇 |
2篇 | |
中国医学 | 238篇 |
肿瘤学 | 10866篇 |
出版年
2023年 | 890篇 |
2022年 | 1492篇 |
2021年 | 3385篇 |
2020年 | 2093篇 |
2019年 | 3132篇 |
2018年 | 3621篇 |
2017年 | 2819篇 |
2016年 | 3157篇 |
2015年 | 3623篇 |
2014年 | 5137篇 |
2013年 | 6903篇 |
2012年 | 10369篇 |
2011年 | 11040篇 |
2010年 | 6395篇 |
2009年 | 6097篇 |
2008年 | 9794篇 |
2007年 | 10274篇 |
2006年 | 10143篇 |
2005年 | 10193篇 |
2004年 | 9331篇 |
2003年 | 8634篇 |
2002年 | 8294篇 |
2001年 | 2184篇 |
2000年 | 1868篇 |
1999年 | 2153篇 |
1998年 | 2053篇 |
1997年 | 1706篇 |
1996年 | 1464篇 |
1995年 | 1358篇 |
1994年 | 1239篇 |
1993年 | 1111篇 |
1992年 | 1319篇 |
1991年 | 1224篇 |
1990年 | 1067篇 |
1989年 | 1025篇 |
1988年 | 957篇 |
1987年 | 926篇 |
1986年 | 932篇 |
1985年 | 910篇 |
1984年 | 950篇 |
1983年 | 810篇 |
1982年 | 984篇 |
1981年 | 889篇 |
1980年 | 753篇 |
1979年 | 658篇 |
1978年 | 654篇 |
1977年 | 551篇 |
1976年 | 538篇 |
1974年 | 511篇 |
1973年 | 449篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
Elizabeth C Frenzel Georgia A Thomas Hend A Hanna 《Infection control and hospital epidemiology》2006,27(5):512-514
At the time of hire, 4059 of 6522 healthcare workers required a 2-step tuberculin skin test; 114 workers (2.8%) demonstrated a boosted reaction after the second step. Boosted reactions were significantly associated with male sex and older age. A verbal history of previous tuberculin skin test results was not a reliable indicator of baseline tuberculin skin test status at the time of hire. 相似文献
12.
This article describes the proceedings of the 2006 Annual Meeting of the Fetal Alcohol Spectrum Disorders Study Group (FASDSG), which was held in Baltimore, Maryland on June 24, 2006. The meeting was held in conjunction with the annual meeting of the Research Society on Alcoholism and was supported by a grant from the National Institute on Alcohol Abuse and Alcoholism. The 2005-2006 FASDSG officers, Daniel J. Bonthius (President), Heather Carmichael Olson (Vice-President), and Jennifer Thomas (Secretary-Treasurer), organized the meeting. Nationally prominent speakers delivered plenary lectures on topics of newborn screening, ethics, and neuroscience. Selected members of the FASDSG provided brief scientific data (FASt) reports, describing new research findings. Representatives from national agencies involved in fetal alcohol syndrome (FAS) research, treatment, and prevention provided updates regarding priorities, funding, and agency activities. Presentations were also made by the 2006 Student Merit Award recipient and by the 2006 Rosett Award recipient. The meeting served as a forum for clinicians, neuroscientists, psychologists, social scientists, and other professionals to discuss recent advances in FAS research and to identify the most important gaps in the understanding of alcohol-induced teratology. 相似文献
13.
Thomas R?mer 《Gynecological endocrinology》2006,22(3):140-144
Bleeding disorders encountered during administration of hormone replacement therapy (HRT) are reviewed. The incidence of bleeding disorders is dependent on the phase of HRT and the age of the patient. In the diagnosis of these bleedings transvaginal sonography and minihysteroscopy are very important methods. Endometrial thickness can be monitored exactly by transvaginal sonography. Outpatient minihysteroscopy without anesthesia results in higher compliance to HRT after the procedure. In hormonal treatment of bleeding disorders during HRT, the sonographically supported progestogen test is very useful and can reduce endometrium thickness. Operative treatments include myoma and polyp resection as well as endometrial ablation. By these methods a high rate of bleeding-free HRT can be reached. The problem of endometrial cancer during HRT is discussed on the basis of new literature and critical statements. The review shows the importance of individual diagnostic and treatment schedules for bleeding disorders during HRT. 相似文献
14.
M M Smith J E Thompson D Thomas M Castillo D Carrier S K Mukherji D Gilliam 《AJNR. American journal of neuroradiology》1997,18(2):327
Choristomas, masses of normal tissues in aberrant locations, contain smooth muscle fibers and fibrous tissues. We describe the MR imaging features of two choristomas located in the internal auditory canals and arising from the facial and vestibulocochlear nerves. Both lesions enhanced with contrast material. In one case, enhancement was seen in the geniculate ganglion and greater superficial petrosal nerve. In the other, a medial component enhanced less than the lateral component did. 相似文献
15.
16.
17.
P Thomas 《British journal of hospital medicine》1990,44(2):133-135
18.
Peter E Murray Thomas W Smyth Imad About Remeille Remusat Jean-Claude Franquin Anthony J Smith 《Journal of dentistry》2002,30(1):29-36
OBJECTIVES: The incidence of bacterial microleakage, pulp inflammation and necrosis associated with dentine etching treatments prior to restoration are not known. Consequently, to resolve some of the controversy surrounding the effects and importance of vital dentine etching, the authors investigated these factors. METHODS: 110 standardised class V cavities were cut into buccal dentine, without exposing the pulp of teeth scheduled for extraction for orthodontic reasons. Cavities were either left unetched, or etched with the non-equivalent treatments of phosphoric acid gel for 60s or Ethylenediaminetetraacetic acid (EDTA) for 30s, prior to placement of composite resin. Teeth were collected and pulp responses were evaluated according to ISO guidelines, using pathohistomorphometric analysis and ANOVA statistics. RESULTS: Etching was found to be correlated to bacterial microleakage (p=0.0001) and tertiary dentine formation (p=0.0023). Bacterial microleakage was correlated to inflammatory activity (p=0.0001). The frequency of bacterial microleakage was: no etching (65%), EDTA (51%) and phosphoric acid (PA) (20%). SIGNIFICANCE: Vital dentine etching treatment is of extreme importance for the placement of RC to minimise bacterial microleakage. PA etching proved to be more effective at preventing bacterial microleakage than non-etching, and etching with EDTA. 相似文献
19.
BACKGROUND: The responses of mice to the mite allergen Der p 1 have been used to study the mechanisms of allergic sensitization and the development of new types of immunotherapy. Many of the studies require a knowledge of the T cell epitopes, and because Der p 1 is polymorphic, the effect of natural amino acid substitution in the allergen. The intranasal administration of peptides containing T cell epitopes can induce a mucosal tolerance but it is not known if the major activity is limited to stimulatory peptides and if, as found for autoimmunity, some epitopes are not inhibitory. OBJECTIVE: To determine and compare the sequences of Der p 1 which contain stimulatory epitopes for the high responding H-2(b) and H-2(q) mice and the sequences which induce tolerance by intranasal administration of peptides. METHODS: T cell responses of mice immunized with Der p 1 were measured by in vitro T cell stimulation assays so an extensive study of epitope recognition and intranasal tolerance could be made. Synthetic peptides were used to examine the stimulatory and inhibitory ability of all Der p 1 sequences and to map the major H-2(b) epitope in detail. This included the effect of the common polymorphic amino acid 124 substitution found within this epitope. RESULTS: Three and two regions, respectively, were found to contain stimulatory T cell epitopes for H-2(b) and H-2(q) mice. The peptides in these regions were also the most active at inducing intranasal tolerance for the responding haplotype. The correspondence between inhibitory and stimulatory peptides was maintained for the fine mapping of the major H-2(b) epitope. This was found about a core region of 118-126 which was overlapping but separate to a consensus sequence for the binding of endogeneous peptides. Peptides with alanine at the naturally polymorphic residue 124 stimulated and inhibited responses to Der p 1 more effectively, while peptides with the valine 124 variant were immunogenic but poorly cross-reactive. CONCLUSIONS: The intranasal administration of peptides representing each of five epitopes recognized by two strains of mice were able to induce mucosal tolerance and the major tolerizing activity was limited to these epitopes. The position of the core major epitope for C57 mice, which differs from a previously predicted epitope, and its specificity for the natural alanine 124 variant is described. 相似文献
20.
Dr. Robert L. Geggel David R. Fulton Harvey L. Chernoff Richard Cleveland Thomas J. Hougen 《Pediatric cardiology》1987,8(4):279-283
Summary An infant girl is described who had cor triatriatum and partial anomalous pulmonary venous connection of the left pulmonary
veins to the coronary sinus, the first report of this combination of lesions. The infant also had a Dandy-Walker malformation
and multiple facial and intrathoracic hemangiomas. The cardiac diagnosis was made by two-dimensional echocardiography. Cardiac
catheterization and angiography confirmed the findings and also demonstrated a persistent left superior vena cava draining
to the coronary sinus. The infant underwent successful surgical repair. Partial anomalous pulmonary venous connection and
left superior vena cava not infrequently are associated with cor triatriatum. Although two-dimensional echocardiography is
sensitive for the detection of cor triatriatum, preoperative cardiac catheterization is necessary to identify unequivocally
systemic and pulmonary venous connections. 相似文献