全文获取类型
收费全文 | 7080篇 |
免费 | 407篇 |
国内免费 | 46篇 |
专业分类
耳鼻咽喉 | 71篇 |
儿科学 | 201篇 |
妇产科学 | 184篇 |
基础医学 | 774篇 |
口腔科学 | 311篇 |
临床医学 | 585篇 |
内科学 | 1672篇 |
皮肤病学 | 191篇 |
神经病学 | 446篇 |
特种医学 | 217篇 |
外国民族医学 | 3篇 |
外科学 | 1149篇 |
综合类 | 152篇 |
一般理论 | 5篇 |
预防医学 | 475篇 |
眼科学 | 157篇 |
药学 | 478篇 |
中国医学 | 40篇 |
肿瘤学 | 422篇 |
出版年
2024年 | 8篇 |
2023年 | 97篇 |
2022年 | 220篇 |
2021年 | 392篇 |
2020年 | 234篇 |
2019年 | 308篇 |
2018年 | 404篇 |
2017年 | 216篇 |
2016年 | 208篇 |
2015年 | 251篇 |
2014年 | 330篇 |
2013年 | 386篇 |
2012年 | 612篇 |
2011年 | 573篇 |
2010年 | 318篇 |
2009年 | 249篇 |
2008年 | 417篇 |
2007年 | 333篇 |
2006年 | 333篇 |
2005年 | 326篇 |
2004年 | 272篇 |
2003年 | 229篇 |
2002年 | 188篇 |
2001年 | 62篇 |
2000年 | 49篇 |
1999年 | 43篇 |
1998年 | 21篇 |
1997年 | 20篇 |
1996年 | 24篇 |
1995年 | 17篇 |
1994年 | 20篇 |
1993年 | 13篇 |
1992年 | 22篇 |
1991年 | 36篇 |
1990年 | 19篇 |
1989年 | 26篇 |
1988年 | 20篇 |
1987年 | 24篇 |
1986年 | 16篇 |
1985年 | 17篇 |
1984年 | 17篇 |
1983年 | 12篇 |
1982年 | 12篇 |
1981年 | 10篇 |
1980年 | 12篇 |
1979年 | 15篇 |
1978年 | 14篇 |
1975年 | 8篇 |
1974年 | 15篇 |
1973年 | 11篇 |
排序方式: 共有7533条查询结果,搜索用时 0 毫秒
991.
H Awwad H A El-Baki N El-Bolkainy M Burgers S El-Badawy M Mansour O Soliman S Omar M Khafagy 《International journal of radiation oncology, biology, physics》1979,5(6):787-794
The present report deals with a prospective randomized study investigating the value of pre-operative telecobalt irradiation in the management of T3-carcinoma in Bilharzial bladder. A total pre-operative dose of 4000 rad was split into 2 equal courses with a gap of 1 week. Two dose-time regimens were compared: split-course conventional fractionation, 200 rad/day (SC) and hyperfractionation (HF). In the latter, the daily dose amounted to 1000 rad and was divided into 17 hourly acute fractions, 60 rad each.The SC and HF regimens produced equivalent local tissue reactions. Hyperfractionation, however, was associated with a somewhat higher incidence of radiation sickness. Both regimens resulted in an increase of the 2-year disease-free survival rate from 19 ± 10% () to 53 ± 9% () without added surgical hazard; both HF and SC appeared to be equally effective.An appreciable post-irradiation tumor shrinkage was noted in the majority of patients; this is consistent with a rapid tumor cell turnover rate. Moreover the likelihood of long term local tumor control seemed to be greater in the more rapidly shrinking tumors. This is proposed to be linked to a more extensive reoxygenation process. No correlation was obtained between the quantitative scoring of the cytohistological radiation effect and the outcome of treatment. 相似文献
992.
993.
A review of acute childhood leukemia in the University Hospital, Kuala Lumpur reveals no significant differences in either the epidemiological or clinical features between Malaysian and Caucasian children. BCG does not appear to have conferred any protection against the occurrence of leukemia. With the introduction of total therapy 4 of 10 patients with good prognostic features and 3 of 15 patients with poor prognostic features have survived 3 years. Prognosis appears to correlate with adopted clinical criteria. 相似文献
994.
995.
This paper addresses three questions: What is the extent of clinical guideline utilization by decision-makers in provincial health ministries, regional health authorities and hospitals in Canada? Are there differences between these work settings in regard to the extent of clinical guideline utilization? What are the determinants of clinical guidelines utilization in health ministries, regional health authorities and hospitals? Based on a survey of 899 decision-makers from Canadian provincial health ministries, regional health authorities and hospitals, the results indicate that there are large differences between work settings in regard to clinical guideline utilization. Not surprisingly, work settings like hospitals rely more intensively on clinical guidelines than the other work settings (health ministries or agencies and regional health authorities). The results of the regression models indicate that cognitive factors, social factors, technological factors, organizational factors and individual attributes significantly predict the utilization of clinical practice guidelines by decision-makers. However, the results of the regression models also indicate that some factors that predict clinical guideline utilization by decision-makers in hospitals do not predict clinical guidelines utilization by decision-makers working in ministries or in regional health authorities. Therefore, these results suggest that customized interventions would be appropriate in order to efficiently increase the utilization of clinical practice guidelines in different work settings. The paper concludes with suggestions for future research. 相似文献
996.
An alkali-extractable polysaccharide (1) was isolated from the seeds of Retama raetam ssp. gussonei. Its composition and linkage determination have been investigated using component analysis, methylation analysis, hydrolysis studies, and NMR spectroscopic analysis. This was shown to contain d-xylose, d-glucose, and 4-O-methyl-d-glucuronic acid in a molar ratio of 7:2:1 and consisted of a backbone of beta-(1-->4)-linked d-xylopyranosyl residues, having branches of alpha-d-glucopyranosyl residues that contain (1-->2)-linkages and 4-O-methyl-alpha-d-glucopyranosyluronic acid at O-2. This is the first report on the isolation of an alkali-extractable polysaccharide from this plant. 相似文献
997.
Anti-plasmodial activity and toxicity of extracts of plants used in traditional malaria therapy in Meru and Kilifi Districts of Kenya 总被引:1,自引:0,他引:1
Kirira PG Rukunga GM Wanyonyi AW Muregi FM Gathirwa JW Muthaura CN Omar SA Tolo F Mungai GM Ndiege IO 《Journal of ethnopharmacology》2006,106(3):403-407
The methanol and aqueous extracts of 10 plant species (Acacia nilotica, Azadirachta indica, Carissa edulis, Fagaropsis angolensis, Harrissonia abyssinica, Myrica salicifolia, Neoboutonia macrocalyx, Strychnos heningsii, Withania somnifera and Zanthoxylum usambarensis) used to treat malaria in Meru and Kilifi Districts, Kenya, were tested for brine shrimp lethality and in vitro anti-plasmodial activity against chloroquine-sensitive and chloroquine-resistant strains of Plasmodium falciparum (NF54 and ENT30). Of the plants tested, 40% of the methanol extracts were toxic to the brine shrimp (LD(50)<100micro/ml), while 50% showed in vitro anti-plasmodial activity (IC(50)<100microg/ml). The methanol extract of the stem bark of N. macrocalyx had the highest toxicity to brine shrimp nauplii (LD(50) 21.04+/-1.8microg/ml). Methanol extracts of the rest of the plants exhibited mild or no brine shrimp toxicity (LD(50)>50microg/ml). The aqueous extracts of N. macrocalyx had mild brine shrimp toxicity (LD(50) 41.69+/-0.9microg/ml), while the rest were lower (LD(50)>100microg/ml). The methanol extracts of F. angolensis and Zanthoxylum usambarense had IC(50) values <6microg/ml while the aqueous ones had values between 6 and 15microg/ml, against both chloroquine-sensitive and resistant P. falciparum strains. The results support the use of traditional herbs for anti-malarial therapy and demonstrate their potential as sources of drugs. 相似文献
998.
999.
Abernethy H Cho C DeLanoy A Khan O Kerns JW Knight K Diehr S 《The Journal of family practice》2006,55(9):801-802
Cryotherapy has similar cure rates to topical salicylate (a pharmacologic therapy) for nongenital common warts (strength of recommendation [SOR]: B, based on systemic review of variable quality randomized trials). Duct tape may be equivalent to cryotherapy (SOR: B, based on a single randomized trial). CO2 laser, photodynamic therapy, pulsed dye laser (PDL), and Er:Yag laser therapies may also be effective for recalcitrant warts (SOR: C, based on observational cohort studies). 相似文献
1000.
Access to current, accurate, and relevant information is mandatory for effective disaster response. In-field observations, reviews of after-action reports, and basic research indicate that this most basic of requirements is not being met. Participating disaster recovery parties, in particular environmental health agencies, lack clarity about their exact roles and lack the most basic of technological solutions that could support any given role definition. There is a need, from both cost and training perspectives, for a single, integrated solution covering risk-based routine inspections, abnormalities, and major incidents. 相似文献