全文获取类型
收费全文 | 25925篇 |
免费 | 1645篇 |
国内免费 | 81篇 |
专业分类
耳鼻咽喉 | 179篇 |
儿科学 | 810篇 |
妇产科学 | 623篇 |
基础医学 | 3910篇 |
口腔科学 | 450篇 |
临床医学 | 3735篇 |
内科学 | 4711篇 |
皮肤病学 | 439篇 |
神经病学 | 2707篇 |
特种医学 | 603篇 |
外科学 | 2101篇 |
综合类 | 176篇 |
一般理论 | 26篇 |
预防医学 | 3002篇 |
眼科学 | 446篇 |
药学 | 1878篇 |
1篇 | |
中国医学 | 57篇 |
肿瘤学 | 1797篇 |
出版年
2024年 | 23篇 |
2023年 | 213篇 |
2022年 | 390篇 |
2021年 | 716篇 |
2020年 | 475篇 |
2019年 | 641篇 |
2018年 | 776篇 |
2017年 | 556篇 |
2016年 | 616篇 |
2015年 | 791篇 |
2014年 | 911篇 |
2013年 | 1460篇 |
2012年 | 2025篇 |
2011年 | 2170篇 |
2010年 | 1130篇 |
2009年 | 1061篇 |
2008年 | 1762篇 |
2007年 | 1831篇 |
2006年 | 1782篇 |
2005年 | 1662篇 |
2004年 | 1574篇 |
2003年 | 1444篇 |
2002年 | 1271篇 |
2001年 | 165篇 |
2000年 | 128篇 |
1999年 | 170篇 |
1998年 | 220篇 |
1997年 | 168篇 |
1996年 | 161篇 |
1995年 | 117篇 |
1994年 | 125篇 |
1993年 | 106篇 |
1992年 | 73篇 |
1991年 | 86篇 |
1990年 | 71篇 |
1989年 | 79篇 |
1988年 | 47篇 |
1987年 | 48篇 |
1986年 | 47篇 |
1985年 | 50篇 |
1984年 | 67篇 |
1983年 | 72篇 |
1982年 | 70篇 |
1981年 | 48篇 |
1980年 | 50篇 |
1979年 | 34篇 |
1978年 | 22篇 |
1977年 | 25篇 |
1976年 | 24篇 |
1974年 | 22篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
1.
2.
3.
4.
BACKGROUND: The 1997 National Asthma Education and Prevention Program (NAEPP) recommends a severity classification scheme to optimize the use of anti-inflammatory therapy for persistent asthma. Physician documentation of asthma severity is often used as a quality assurance measure. OBJECTIVE: To test the hypothesis that physician documentation of asthma severity is associated with appropriate use of anti-inflammatory therapy. DESIGN/METHODS: Setting: inner-city academic health center. First, we reviewed a consecutive sample of charts of scheduled pediatric patients. Then, we administered a structured parent survey regarding the child's asthma symptoms and current asthma therapy. We used NAEPP guidelines to classify patients' severity of asthma. The main outcome measure was appropriate use of anti-inflammatory therapy. Appropriate therapy was defined as: (1) mild persistent asthmatics using anti-inflammatory therapy, and (2) moderate-severe persistent asthmatics using inhaled steroids. Chart classification of asthma severity was compared with the NAEPP-applied classification. RESULTS: Of 784 charts, 214 (27%) were asthmatic. Of these, 176 (82%) were surveyed. The mean age was 7.4 years; 61% were males. Severity classification was documented in 77% of charts. Chart documentation differed significantly from survey classification for the same patients: (mild intermittent 54% vs. 40%, mild persistent 21% vs. 14%, moderate persistent 24% vs. 36%, severe persistent 1% vs. 10%; all p < .001). Correctly classified patients were more likely to be on appropriate therapy. CONCLUSIONS: Physicians underestimated the severity classification of asthmatic patients. Incorrect classification was associated with inappropriate asthma therapy. These findings have implications for the institution of asthma quality improvement programs. 相似文献
5.
6.
The use of computer technology for patient education has increased in recent years. This article describes a study that measures the attitudes and perceptions of healthcare professionals and laypeople regarding the effectiveness of a multimedia computer, the Brain Injury Resource Center? (BIRC), as an educational tool. The study focused on three major themes: (a) usefulness of the information presented, (b) effectiveness of the multimedia touch-screen computer methodology, and (c) the appropriate time for making this resource available. This prospective study, conducted in an acute care medical center, obtained healthcare professionals' evaluations using a written survey and responses from patients with brain injury and their families during interviews. The findings have yielded excellent ratings as to the ease of understanding and usefulness of the BIRC. By using sight, sound, and touch, such a multimedia learning center has the potential to simplify patient and family education. 相似文献
7.
8.
ngela P. de Mattos Tereza C.M. Ribeiro Patrícia S.A. Mendes Sandra S. Valois Carlos M.C. Mendes Hugo C. Ribeiro Jr 《Nutrition Research》2009,29(7):462-469
Although previous studies have shown successful treatment of persistent diarrhea (PD) with the use of yogurt-based diets, some recent ones speculate the need of special formulas for the nutritional management of PD complicated cases. In the present study, we tested the hypothesis that the consumption of 3 lactose-free diets, with different degrees of complexity, is associated with lower stool output and shorter duration of diarrhea when compared with the use of a yogurt-based one on the nutritional management of PD. A total of 154 male infants, aged between 1 and 30 months, with PD and with or without dehydration, were randomly assigned to 1 of 4 treatment groups. Throughout the study, the patients were placed in a metabolic unit; their body weights and intakes of oral rehydration solution, water, and formula diets, in addition to outputs of stool, urine, and vomit, were measured and recorded at 24-hour intervals. Four different diets were used in this study: diet 1, yogurt-based formula; diet 2, soy-based formula; diet 3, hydrolyzed protein-based formula; and diet 4, amino acid–based formula. Throughout the study, only these formula diets were fed to the children. The data showed that children fed the yogurt-based diet (diet 1) or the amino acid–based diet (diet 4) had a significant reduction in stool output and in the duration of diarrhea. The use of an inexpensive and worldwide-available yogurt-based diet is recommended as the first choice for the nutritional management of mild to moderate PD. For the few complicated PD cases, when available, a more complex amino acid–based diet should be reserved for the nutritional management of these unresponsive and severe presentations. Soy-based or casein-based diets do not offer any specific advantage or benefits and do not seem to have a place in the management of PD. 相似文献
9.
Age determines memory for face identity and expression 总被引:1,自引:1,他引:0
Egemen SAVASKAN Sandra Elisabeth MÜLLER reas BÖHRINGER Christine PHILIPPSEN Franz MÜLLER-SPAHN Hartmut SCHÄCHINGER 《Psychogeriatrics》2007,7(2):49-57
Background: The recognition of facial expressions is an important component of emotion processing which contributes to interactional behavior. One of the factors highly associated with potential decline of ability in behavioral tasks is age. Methods: We have investigated age‐related changes in facial identity and expression memory of healthy subjects in three age groups: young adults (20–40 years), elderly adults (60–80 years) and, for the first time in the literature, very old adults (over 80 years of age). Using a picture test, photographs of faces with happy or angry expressions were presented to study participants during the encoding task, and the memory for identity and emotional facial expression was investigated in a subsequent recognition task showing emotionally neutral faces. Half of the faces presented in the recognition task were initially shown in the encoding task. Results: Age interacted with the memory process: the ability to recognize both facial identity and emotional expression declined with advanced age. Happy facial expressions were better recognized in all age groups. Although there was a continuous overall decrease in recognition of both happy and angry expressions with advanced age, the effect favoring happy facial expressions was stable also in very old adults. Other factors such as gender or educational level did not affect the memory process for facial expressions. Conclusions: Our findings suggest that age is a significant determinant of memory for facial identity and emotional expression, and that, similar to younger adults, the recognition process of the elderly favors happy emotional facial expressions. 相似文献
10.
Usher syndrome: clinical findings and gene localization studies 总被引:3,自引:0,他引:3
William J. Kimberling Sandra L. H. Davenport Ira Priluck Valorie White Karen Biscone-Halterman Patrick E. Brookhouser Claes G. Mller Gunnar Lund Timothy J. Grissom Michael D. Weston 《The Laryngoscope》1989,99(1):66-72
The issue of genetic heterogeneity is a critical problem in the localization of the gene(s) for Usher syndrome. Based on the data obtained on families studied to date, the differences between type I and type II Usher syndrome appear quite distinct with regard to auditory and vestibular function. Although the majority of families can be confidently diagnosed as typical type I or type II, clinical investigations revealed four families with findings that did not fit into either of the two more common subtypes. These findings emphasize the critical importance of an in-depth clinical analysis concomitant with the linkage investigation to assure accurate subtyping of Usher syndrome. Based on an analysis of only those families with definite type I or type II Usher syndrome, approximately 17% of the genome can be excluded as a potential site of the gene for type I, and 14% can be excluded as the site for the type II gene. This study will continue until the Usher gene(s) is successfully localized. 相似文献