全文获取类型
收费全文 | 20473篇 |
免费 | 2533篇 |
国内免费 | 288篇 |
专业分类
耳鼻咽喉 | 159篇 |
儿科学 | 854篇 |
妇产科学 | 189篇 |
基础医学 | 2146篇 |
口腔科学 | 1661篇 |
临床医学 | 1367篇 |
内科学 | 4322篇 |
皮肤病学 | 641篇 |
神经病学 | 1784篇 |
特种医学 | 297篇 |
外国民族医学 | 3篇 |
外科学 | 1359篇 |
综合类 | 1330篇 |
现状与发展 | 6篇 |
预防医学 | 3884篇 |
眼科学 | 536篇 |
药学 | 640篇 |
4篇 | |
中国医学 | 114篇 |
肿瘤学 | 1998篇 |
出版年
2024年 | 23篇 |
2023年 | 328篇 |
2022年 | 269篇 |
2021年 | 848篇 |
2020年 | 861篇 |
2019年 | 841篇 |
2018年 | 883篇 |
2017年 | 847篇 |
2016年 | 849篇 |
2015年 | 880篇 |
2014年 | 1199篇 |
2013年 | 1667篇 |
2012年 | 978篇 |
2011年 | 1178篇 |
2010年 | 944篇 |
2009年 | 977篇 |
2008年 | 997篇 |
2007年 | 940篇 |
2006年 | 883篇 |
2005年 | 727篇 |
2004年 | 720篇 |
2003年 | 675篇 |
2002年 | 637篇 |
2001年 | 506篇 |
2000年 | 323篇 |
1999年 | 299篇 |
1998年 | 305篇 |
1997年 | 349篇 |
1996年 | 280篇 |
1995年 | 249篇 |
1994年 | 209篇 |
1993年 | 177篇 |
1992年 | 191篇 |
1991年 | 181篇 |
1990年 | 152篇 |
1989年 | 145篇 |
1988年 | 118篇 |
1987年 | 101篇 |
1986年 | 106篇 |
1985年 | 83篇 |
1984年 | 57篇 |
1983年 | 60篇 |
1982年 | 45篇 |
1981年 | 45篇 |
1980年 | 42篇 |
1979年 | 25篇 |
1978年 | 18篇 |
1977年 | 23篇 |
1976年 | 16篇 |
1974年 | 14篇 |
排序方式: 共有10000条查询结果,搜索用时 218 毫秒
51.
Abstract – The dental records made on presentation of 1367 consecutive patients (731 females and 636 males) for orthodontic treatment at a private orthodontic practice between 1998 and 2002 were examined for data relating to trauma to the permanent incisors. The results showed that 10.3% of these patients had suffered from dental trauma before the onset of orthodontic treatment. The highest prevalence of dental trauma was determined in the 11–15 years age group, corresponding to the dental developmental stage of the late mixed dentition. The most frequently affected teeth were the maxillary central incisors (79.6%), and the most common types of trauma were fracture of enamel–dentin without pulpal involvement (42.7%) and fracture of enamel (33.8%). Compared to patients with normal overjet and adequate lip coverage, the frequency of dental trauma was significantly higher in patients with increased overjet and adequate lip coverage ( P = 0.028) or with increased overjet and inadequate lip coverage ( P = 0.003). The results of the present study indicate that a significant percentage of candidates for orthodontic treatment, and especially those with increased overjet and inadequate lip coverage, suffer trauma to their permanent incisors before the onset of orthodontic treatment. It might also be concluded that preventive orthodontic treatment of such patients should be initiated and completed before the age of 11, i.e. in the early to middle mixed dentition. 相似文献
52.
Njideka U Okubadejo James H Bower Walter A Rocca Demetrius M Maraganore 《Movement disorders》2006,21(12):2150-2156
Parkinson's disease (PD) occurs worldwide, but little is known about PD in Africa. We systematically reviewed publications on PD in Africa, with emphasis on epidemiologic and genetic studies. Articles published between 1944 and December 2004 were identified using several strategies. The studies emanated from 13 African countries (Kenya, Uganda, Tanzania, Ethiopia, Nigeria, Senegal, Ghana, Togo, Libya, Tunisia, Algeria, Zimbabwe, and South Africa). The publications fell into four categories: clinical series (n = 17), prevalence studies (n = 7), incidence studies (n = 1), and genetic studies (n = 3). The clinical series documented the occurrence of PD in Africa and described its clinical characteristics. The prevalence studies suggested some intracontinental geographic variation in PD prevalence. Overall, the prevalence figures and the incidence rates of PD in Africa appeared lower than those reported for European and North American populations. Few genetic studies of PD have been reported from Africa, and none in blacks. There are no case-control or cohort studies of PD reported from Africa. This review provides a summary of PD research in Africa over the past 60 years and highlights the information gaps and potential areas for future research. 相似文献
53.
L. J. Stovner J.-A. Zwart K. Hagen G. M. Terwindt J. Pascual 《European journal of neurology》2006,13(4):333-345
The present review of epidemiologic studies on migraine and headache in Europe is part of a larger initiative by the European Brain Council to estimate the costs incurred because of brain disorders. Summarizing the data on 1-year prevalence, the proportion of adults in Europe reporting headache was 51%, migraine 14%, and 'chronic headache' (i.e. > or =15 days/month or 'daily') 4%. Generally, migraine, and to a lesser degree headache, are most prevalent during the most productive years of adulthood, from age 20 to 50 years. Several European studies document the negative influence of headache disorders on the quality of life, and health-economic studies indicate that 15% of adults were absent from work during the last year because of headache. Very few studies have been performed in Eastern Europe, and there are also surprisingly little data on tension-type headache from any country. Although the methodology and the quality of the published studies vary considerably, making direct comparisons between different countries difficult, the present review clearly demonstrates that headache disorders are extremely prevalent and have a vast impact on public health. The data collected should be used as arguments to increase resources to headache research and care for headache patients all over the continent. 相似文献
54.
M. Trakatelli† C. Ulrich† V. del Marmol‡ S. Euvrard§ E. Stockfleth† D. Abeni¶ 《The British journal of dermatology》2007,156(S3):1-7
Summary Nonmelanoma skin cancer (NMSC) is the most common malignancy occurring in white populations. It is currently becoming an important challenge in terms of public health management as the increasing incidence rates will probably have a tremendous impact on healthcare costs. Possible factors driving this rise in NMSC numbers are increases in both acute and prolonged UV exposure together with increasing numbers of older people in the population. A better understanding of NMSC epidemiology in Europe is essential if an evidence-based European-wide public health policy is to be developed. It is obvious this can only be achieved by recording and analysing comparative epidemiological data. Finally, by improving the skin examination training for physicians, developing guidelines and exchanging best practices, a high level of healthcare could be provided for NMSC. 相似文献
55.
目的:了解严重急性呼吸综合征(SARS)死亡病例的临床特点,为SARS重症病例的诊断、治疗及预后判断提供帮助。方法:对我院2003年1月至4月底收治的102例确诊非典患者中的5例死亡病例的流行病学及实验室检查资料进行回顾性分析。结果:死亡病例均为男性,平均49岁,从发病到入院平均7.6d,从住院到确诊平均1.2d;从住院到死亡平均14.4d,从发病到死亡平均为22d。死亡病例粒细胞总数和百分比均明显升高,多数患者淋巴细胞计数和百分比降低(4/5),血红蛋白均呈进行性下降。死亡患者除已见报道的ALT、AST、LDH、CK升高及低钙血症外,GLU均明显高于正常而ALB均明显降低;大多数患者TP、PA等多项生化指标均出现明显下降而脱氧血红蛋白百分率(HHb)明显上升,同时伴有低磷、低镁血症。结论:SARS死亡病例多项实验室指标均会出现明显异常,动态监测这些指标有助于SARS患者的诊断、治疗及预后判断。 相似文献
56.
57.
目的:了解本地区性病病原体的感染情况。方法:对金山医院性病门诊1289例患者的相关临床资料进行统计,并做流行病学分析。结果:1289例患者中,淋病582例,占45.15%;非淋菌性尿道炎753例,占58.42%,尖锐湿疣170例,占13.19%;梅毒8例,占0.62%。结论:非淋菌性尿道炎发病率最高,男女患者病原体感染差异显著,男性以淋病奈瑟菌为主,而女性则以沙眼衣原体为多,在临床诊治时应引起高度重视。 相似文献
58.
Summary. A method is presented for the standardization of Candida albicans DNA fingerprinting, which is based on Southern hybridization of Eco RI-digested chromosomal DNA with the moderately repetitive DNA element CARE-2 and the subsequent rehybridization of the blots with a molecular size marker also included in each DNA sample. This method resulted in extremely precise alignment of all strain-specific CARE-2 hybridization patterns, even when analysed on different gels, and will enhance the accuracy of genetic relationship determinations in epidemiological studies including large numbers of strains.
Zusammenfassung. Zur Standardisierung des DNA-Fingerprinting von Candida albicans wurde eine Methode entwickelt, die auf der Southern Hybridisierung Eco RI-gespaltener chromosomaler DNA mit dem mittelrepetitiven DNA-Element CARE-2 und der darauffolgenden Rehybridisierung der Blots mit einem auch in den Proben enthaltenen molekularen Größenmarker beruht. Dies resultierte in einer äußerst präzisen Größen-bestimmung der hybridisierenden Fragmente, so daß alle stammspezifischen CARE-2-Hybridisierungsmuster exakt verglichen werden konnten, auch wenn die Isolate auf verschiedenen Gelen analysiert wurden. Die Methode erhöht die Genauigkeit der Bestimmung genetischer Verwandtschaftsbeziehungen in epidemiologischen Untersuchungen, in denen eine große Anzahl von Stämmen analysiert wird. 相似文献
Zusammenfassung. Zur Standardisierung des DNA-Fingerprinting von Candida albicans wurde eine Methode entwickelt, die auf der Southern Hybridisierung Eco RI-gespaltener chromosomaler DNA mit dem mittelrepetitiven DNA-Element CARE-2 und der darauffolgenden Rehybridisierung der Blots mit einem auch in den Proben enthaltenen molekularen Größenmarker beruht. Dies resultierte in einer äußerst präzisen Größen-bestimmung der hybridisierenden Fragmente, so daß alle stammspezifischen CARE-2-Hybridisierungsmuster exakt verglichen werden konnten, auch wenn die Isolate auf verschiedenen Gelen analysiert wurden. Die Methode erhöht die Genauigkeit der Bestimmung genetischer Verwandtschaftsbeziehungen in epidemiologischen Untersuchungen, in denen eine große Anzahl von Stämmen analysiert wird. 相似文献
59.
Incidence and prevalence of the sexual dysfunctions: A critical review of the empirical literature 总被引:11,自引:0,他引:11
The research which has assessed the incidence and prevalence of sexual dysfunctions is reviewed. Twenty-three studies are evaluated. Studies completed with community samples indicate a current prevalence of 5–10% for inhibited female orgasm, 4–9% for male erectile disorder, 4–10% for inhibited male orgasm, and 36–38% for premature ejaculation. Stable community estimates with regard to the current prevalence of female sexual arousal disorder, vaginismus, and dyspareunia are not available. Recent studies completed with clinical samples suggest an increase in the frequency of orgasmic and erectile dysfunction and a decrease in premature ejaculation as presenting problems. Desire disorders have increased as presenting problems in sex clinics, with recent data indicating that males outnumber females. Methodological limitations of these studies are identified and suggestions for future research are offered. 相似文献
60.
Reiner Mengel Matthias Eigenbrodt Thomas Schünemann Lavin Florès-de-Jacoby 《Journal of clinical periodontology》1996,23(5):437-443
Abstract From August to October 1991, the periodontal status of 1001 Yemenis representing the age groups 12-14, 15-19, 20-24 and 35-44 years was recorded and evaluated with preference to the CPITN, the calculus index and clinical attachment levels. The impact of chewing khat, the leaves of a cultivated, alkaloid shrub, and of using the traditional miswak chewing stick for oral hygiene purposes were investigated. The results show that 6.9% of the juvenile probands (15-19 years) had healthy periodontal tissue (CPITN 0). whereas bleeding on probing and calculus (CPITN 1+2) were registered in 86.2%. In the 35-44 year age group. 1.7% were periodontally healthy, whereas 84.5% displayed plaque retention or shallow pocketing (CPITN 2-3) and 12.5% deep pocketing (CPITN 4). The treatment needs in all age groups are confined primarily to calculus removal and instruction in oral hygiene. The clinical attachment level and the calculus index revealed age-related attachment loss and calculus formation, primarily among male probands. The higher khat consumption among the male population is reflected in its detrimental effect on the periodontal tissue, especially among younger probands. Oral hygiene aids have also an influence on periodontal status, with a toothbrush proving more efficient than the miswak. WHO efforts directed towards prophylactic programs need to be intensified but can be staffed by dental hygienists. 相似文献