全文获取类型
收费全文 | 2896154篇 |
免费 | 233946篇 |
国内免费 | 5504篇 |
专业分类
耳鼻咽喉 | 42739篇 |
儿科学 | 88452篇 |
妇产科学 | 78453篇 |
基础医学 | 409627篇 |
口腔科学 | 84135篇 |
临床医学 | 262351篇 |
内科学 | 561669篇 |
皮肤病学 | 58937篇 |
神经病学 | 243201篇 |
特种医学 | 116017篇 |
外国民族医学 | 1042篇 |
外科学 | 440450篇 |
综合类 | 72589篇 |
现状与发展 | 3篇 |
一般理论 | 1168篇 |
预防医学 | 234054篇 |
眼科学 | 69482篇 |
药学 | 216305篇 |
4篇 | |
中国医学 | 5376篇 |
肿瘤学 | 149550篇 |
出版年
2018年 | 28656篇 |
2016年 | 24575篇 |
2015年 | 27906篇 |
2014年 | 40273篇 |
2013年 | 61522篇 |
2012年 | 82854篇 |
2011年 | 87364篇 |
2010年 | 51389篇 |
2009年 | 49125篇 |
2008年 | 82877篇 |
2007年 | 88740篇 |
2006年 | 89348篇 |
2005年 | 87229篇 |
2004年 | 84420篇 |
2003年 | 81512篇 |
2002年 | 80246篇 |
2001年 | 130055篇 |
2000年 | 134522篇 |
1999年 | 113955篇 |
1998年 | 33508篇 |
1997年 | 30571篇 |
1996年 | 30152篇 |
1995年 | 29145篇 |
1994年 | 27461篇 |
1993年 | 25582篇 |
1992年 | 93033篇 |
1991年 | 89796篇 |
1990年 | 86905篇 |
1989年 | 83729篇 |
1988年 | 78032篇 |
1987年 | 77050篇 |
1986年 | 72887篇 |
1985年 | 69955篇 |
1984年 | 53459篇 |
1983年 | 45723篇 |
1982年 | 28245篇 |
1981年 | 25254篇 |
1980年 | 23768篇 |
1979年 | 51286篇 |
1978年 | 36338篇 |
1977年 | 30606篇 |
1976年 | 28607篇 |
1975年 | 30340篇 |
1974年 | 37529篇 |
1973年 | 35878篇 |
1972年 | 33645篇 |
1971年 | 31093篇 |
1970年 | 29408篇 |
1969年 | 27656篇 |
1968年 | 25158篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
Colin J McKay 《World journal of surgery》2006,30(12):2234-2235
92.
B Nkgudi K A Robertson J Volmink B M Mayosi 《Suid-Afrikaanse tydskrif vir geneeskunde》2006,96(3):206-208
OBJECTIVE: To determine whether under-reporting of rheumatic fever occurs at hospital, municipal, provincial and national levels of the South African health system. BACKGROUND: Information on the incidence of rheumatic fever (RF) and the prevalence of rheumatic heart disease (RHD) is required for the prevention of valvular heart disease in developing countries. In South Africa, RF was made a notifiable condition in 1989. It has recently been suggested that the reporting of RF cases may be incomplete, possibly because of underreporting by health care professionals and deficient administration of the disease notification system in South Africa. METHOD AND RESULTS: We assessed whether underreporting of RF cases occurs by comparing the numbers of RF cases reported per year at hospital, municipal, provincial and national levels from 1990 to 2004. There was a fall in the number of RF cases reported per year at national and provincial level over the 15 years of observation. A detailed analysis of the number of RF cases reported at hospital, municipal and provincial level for a 5-year period showed that more cases were diagnosed in one hospital (serving a smaller population) than were captured at municipal and provincial level (serving a larger population), suggesting underreporting by health care professionals. There were discrepancies in the number of cases reported at municipal, provincial and national level, suggesting poor administration of the notification system. CONCLUSION: There appears to be underreporting of RF cases by health care professionals, and poor administration of the RF notification system. Health care professionals need to be educated about the statutory requirement to notify all RF cases in South Africa. An effective national disease notification system is required. 相似文献
93.
94.
95.
96.
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
97.
98.
A Sharma H L Goh N Asokananthan A Bakker G A Stewart H W Mitchell 《The European respiratory journal》2006,27(1):20-28
Mucosal trypsin, a protease-activated receptor (PAR) stimulant, may have an endogenous bronchoprotective role on airway smooth muscle. To test this possibility the effects of lumenal trypsin on airway tone in segments of pig bronchus were tested. Bronchial segments from pigs were mounted in an organ chamber containing Kreb's solution. Contractions were assessed from isovolumetric lumen pressure induced by acetylcholine (ACh) or carbachol added to the adventitia. Trypsin, added to the airway lumen (300 microg x mL(-1)), had no immediate effect on smooth muscle tone but suppressed ACh-induced contractions after 60 min, for at least 3 h. Synthetic activating peptides (AP) for PAR1, PAR2 or PAR3 were without effect, but PAR4 AP caused rapid, weak suppression of contractions. Lumenal thrombin was without effect and did not prevent the effects of trypsin. Effects of trypsin were reduced by N(omega)-nitro-L-arginine methyl ester but not indomethacin. Trypsin, thrombin and PAR4 AP released prostaglandin E2. Adventitially, trypsin, thrombin and PAR4 AP (but not PAR2 AP) relaxed carbachol-toned airways after <3 min. The findings of this study show that trypsin causes delayed and persistent bronchoprotection by interacting with airway cells accessible from the lumen. The signalling mechanism may involve nitric oxide synthase but not prostanoids or protease-activated receptors. 相似文献
99.
Y Ohtsuka X-T Wang J Saito T Ishida M Munakata 《The European respiratory journal》2006,28(5):1013-1019
Inter-individual variations in the development of silicosis, even within the same environments, have been reported, which suggest the contribution of genetic factors in silicosis aetiology. The aim of the present study was to determine whether there is any significant genetic influence on the development of silicosis. Furthermore, which genetic loci are responsible for the pulmonary response to silica exposure? Eight strains of inbred mice were used to examine the genetic influence on the lung fibrotic response to silica exposure. After intercross-breeding between the most susceptible and most resistant strains, a genome-wide linkage analysis of quantitative trait loci (QTL) was performed. Hydroxyproline was applied as an index, and genotypes of 167 marker genes were analysed by fragment analysis using a capillary-type sequencer. There was significant inter-strain difference in the mean concentration of hydroxyproline contents among the eight strains of mice. Breeding studies were conducted between the most susceptible, C57BL/6J, and the most resistant strain, CBA/J. A genome-wide linkage analysis of silica-exposed intercrossed cohorts identified significant QTL on chromosome 4 and suggestive QTL on chromosomes 3 and 18. The present study demonstrates that genetic factors may play a significant role in fibrotic-lung responses to silica; one significant and two suggestive quantitative trait loci were identified. 相似文献
100.
AIMS: To establish all-cause and cause-specific death rates, and risk factors for mortality in insulin-treated diabetic individuals living in the province of Canterbury, New Zealand. METHODS: Insulin-treated diabetic subjects (n = 995) on the Canterbury Diabetes Registry were followed up over 15 years and vital status determined. Death rates were standardized and hazard regression was used to model the effects of demographic covariates on relative survival time. RESULTS: There were 419 deaths in 11 226.3 person-years of follow-up with a standardized mortality ratio (SMR) of 2.0 (95% confidence interval (CI) 1.8-2.2). Relative mortality was greatest for the group aged 0-29 years (SMR 3.0 (95% CI 2.4-3.7)). After controlling for diabetes duration and gender, a 10-year increment in age of onset was associated with a 33% decrease in relative hazard (95% CI 29-36%), indicating that excess mortality due to diabetes declines with rising age of onset. After controlling for age of onset and gender, each 10-year increment in duration of diabetes is associated with a 26% decrease in relative hazard (95% CI 24-29%), indicating that with longer survival the mortality hazard approaches the general population hazard. Relative mortalities were increased for cardiovascular, renal and respiratory disease, but not malignancy. Relative mortality from acute metabolic complications was increased in the subgroup with age of onset of diabetes < 30 years and requiring insulin within 1 year of diagnosis. CONCLUSIONS: Mortality rates are high for insulin-treated diabetic individuals relative to the general population. 相似文献