全文获取类型
收费全文 | 1189篇 |
免费 | 97篇 |
国内免费 | 8篇 |
专业分类
耳鼻咽喉 | 17篇 |
儿科学 | 94篇 |
妇产科学 | 22篇 |
基础医学 | 188篇 |
口腔科学 | 47篇 |
临床医学 | 112篇 |
内科学 | 262篇 |
皮肤病学 | 29篇 |
神经病学 | 51篇 |
特种医学 | 141篇 |
外科学 | 83篇 |
综合类 | 42篇 |
预防医学 | 117篇 |
眼科学 | 31篇 |
药学 | 16篇 |
肿瘤学 | 42篇 |
出版年
2023年 | 4篇 |
2022年 | 15篇 |
2021年 | 17篇 |
2020年 | 11篇 |
2019年 | 26篇 |
2018年 | 33篇 |
2017年 | 15篇 |
2016年 | 43篇 |
2015年 | 34篇 |
2014年 | 48篇 |
2013年 | 69篇 |
2012年 | 46篇 |
2011年 | 46篇 |
2010年 | 63篇 |
2009年 | 58篇 |
2008年 | 35篇 |
2007年 | 45篇 |
2006年 | 34篇 |
2005年 | 46篇 |
2004年 | 30篇 |
2003年 | 39篇 |
2002年 | 18篇 |
2001年 | 22篇 |
2000年 | 25篇 |
1999年 | 20篇 |
1998年 | 42篇 |
1997年 | 44篇 |
1996年 | 45篇 |
1995年 | 40篇 |
1994年 | 22篇 |
1993年 | 28篇 |
1992年 | 8篇 |
1991年 | 15篇 |
1990年 | 7篇 |
1989年 | 20篇 |
1988年 | 21篇 |
1987年 | 13篇 |
1986年 | 17篇 |
1985年 | 17篇 |
1984年 | 9篇 |
1983年 | 23篇 |
1982年 | 7篇 |
1981年 | 13篇 |
1980年 | 9篇 |
1979年 | 6篇 |
1978年 | 4篇 |
1977年 | 12篇 |
1976年 | 9篇 |
1971年 | 3篇 |
1965年 | 3篇 |
排序方式: 共有1294条查询结果,搜索用时 31 毫秒
21.
To find out the efficacy of sucralfate in preventing gastrointestinal side effects of non-steroidal anti-inflammatory drugs (NSAIDs) a prospective, randomised single blind study was conducted from 1989 to 1992. Patients with osteoarthritis, rheumatoid arthritis and other long standing painful conditions, who were expected to receive NSAIDs for over three months, were recruited into the study. All medicines were discontinued for a period of 10–15 days prior to initial endoscopic assessment. NSAID therapy was started and the patients were randomised to receive either placebo (group A) or sucralfate (group B) in addition. Patient were reassessed clinically every week and an endoscopic examination was repeated after 6–8 weeks of follow-up. A total of 176 patients were studied in group A (n=91) and group B (n=85). At the end of 8 weeks gastrointestinal symptoms were present in 30.6% and 26.4% patients of group A and B respectively. Endoscopic assessment showed superficial lesions in 36.5% and 18.7% while endoscopic ulcer in 2.4% and 1.1% patients of groups A and B respectively. Thus in patients receiving chronic NSAID therapy, simultaneous administration of sucralfate reduces the incidence of superficial gastric lesions but has no significant effect on symptoms or ulcer formation.KEY WORDS: Gastropathy, Sucralfate, Nonsteroidal anti-inflammatory drugs 相似文献
22.
Increasing the utilization of cost-effective health services through changes in demand 总被引:1,自引:0,他引:1
Attaining efficiency in a health care system with a budget constraint involves increasing the utilization of the most cost-effective services. This can be achieved by adjustments to prices, cost curves, or demand curves. In this paper, the potential for demand curve adjustments is examined by selecting two apparently cost-effective services (prenatal care and childhood immunization against tuberculosis), and analyzing the factors explaining their utilization. Data from recent household surveys in Burkina Faso and Niger are used. A multivariate analysis of utilization employs income, price, and taste variables. Utilization is highly sensitive to the distance which must be travelled to the health facility, a price, and taste variables. Utilization is highly sensitive to the distance which must be travelled to the health facility, a price variable. Members of certain ethnic groups tend to use the services less, other things being equal. The importance of demand-side factors like ethnicity points to certain kinds of policy interventions like information, education and communication activities which could increase the utilization of cost-effective services. 相似文献
23.
We report three cases of pernicious anemia diagnosed in women in Africa. All three women had macrocytic anemia with megaloblasts evident on medullogram. The patients had neurological signs of combined sclerosis and the presence of megaloblasts confirmed the diagnosis of pernicious anemia. All were successfully treated parenterally with vitamins. This disease seems to be underdiagnosed in Africa given the number of cases reported in previous studies. 相似文献
24.
Interbody arthrodesis using a plasmapore titanium block. Mechanical and histological experimental study in sheep 总被引:4,自引:0,他引:4
Tropiano P Diop A Dejou J Bronsard JJ Poitout DG 《Chirurgie; mémoires de l'Académie de chirurgie》1999,124(1):58-65
A Plasmapore-coated titanium alloy block was implanted in ewes for the purpose of providing interbody fusion. Four blocks were implanted in each ewe: one uncoated block (without Plasmapore) serving as a reference specimen and three blocks coated with Plasmapore. Mechanical testing and histological study were performed on five ewes. OBJECTIVES: Determination of the quality of the mechanical and histological anchorage of the Plasmapore implanted in the interbody space in the same animal living under conditions of physical strain exerted on the spine. METHODS: Four months after surgical implantation of the block, the ewes were sacrificed: the removed spines were frozen for subsequent mechanical analysis and preserved in a solution of 40 degrees alcohol for subsequent histological analysis. X-rays were taken to evaluate the positioning of the implant. The mechanical analysis included extraction tests, measuring the maximum extraction force and evaluating the stiffness of the system, being indicative of the mechanical fixation quality. The histological study included both qualitative and quantitative analysis, together with an evaluation of the osteointegration of the blocks coated with Plasmapore. RESULTS: After 4 months of implantation, a mean extraction force of 990 N was necessary for the blocks coated with Plasmapore, and of 1.338 N for the blocks coated with Plasmapore with additional osteosynthesis, whereas a mean extraction force of 332 N was necessary for the uncoated blocks. Anchorage and resistance against uprooting of the blocks coated with Plasmapore were significantly more efficient. The histological study revealed the presence of bone neoformation adhering to the implant. Quantification of this bone formation covering nearly 45% of the implant perimeter, confirmed both osteointegration of the implant perimeter, confirmed both osteointegration of the implant surfaces being in contact with the vertebral endplates and osteoconduction along the lateral surfaces. CONCLUSION: The titanium Plasmapore block enables interbody fusion due to an osteointegration of the vertebral endplates by Plasmapore coating, which was proved by the results of extraction testing and histological study. It should be taken into account that no additional bone grafts have been used and that the implant had not been forced into the spongiosa. 相似文献
25.
JP Bound PW Harvey BJ Francis F Awwad AC Gatrell 《Archives of disease in childhood》1997,76(2):107-112
OBJECTIVE: To analyse the prevalence of neural tube defects in small geographical areas and seek to explain any spatial variations with reference to environmental lead and deprivation. SETTING: The Fylde of Lancashire in the north west of England. DESIGN: Cases were ascertained as part of a prospective survey of major congenital malformations in babies born in the Fylde to residents there between 1957 and 1981. A matched case-control analysis used infants with cardiovascular system, alimentary tract, and urinary system malformations as controls. Conditional logistic regression was used to assess the effects of more than 10 micrograms/l lead in drinking water and the Townsend deprivation score. RESULTS: The prevalence of neural tube defects in 1957-73 was higher in Blackpool, Fleetwood, and North Fylde, whereas the three control groups showed no significant spatial variation. In 1957-81 mothers living in electoral wards with either a higher proportion of houses with more than 10 micrograms/l lead in the water or a higher deprivation score had a greater risk of having a baby with a neural tube defect. For spina bifida and cranium bifidum alone, this was also true. For anencephaly, deprivation was less important although the effect of lead was still seen. In some neural tube defects, lead may act independently of other possible factors associated with deprivation. It seemed unlikely that lead levels changed significantly during the survey. The percentage of houses with 10 micrograms/l or more of lead in the water in 1984-5 was similar to that found in Great Britain 10 years previously. CONCLUSION: There is evidence to suggest that lead is one cause of neural tube defects, especially anencephaly. This could link the known preventive actions of hard water and folic acid. Calcium is a toxicological antagonist of lead. One cause of a deficiency of folic acid is impaired absorption secondary to zinc deficiency, which may be produced or exacerbated by lead. 相似文献
26.
FJ O'Callaghan AC Clarke H Joffe B Keeton R Martin A Salmon RD Thomas JP Osborne 《Archives of disease in childhood》1998,78(2):159-162
This report highlights the association between tuberous sclerosis and Wolff-Parkinson-White syndrome. Ten patients with concurrent diagnoses of Wolff-Parkinson-White syndrome and tuberous sclerosis were identified. Wolff-Parkinson-White syndrome presented early in life, nine cases being diagnosed in the first year. Eight of the 10 cases were male. In eight cases, the syndrome was associated with supraventricular tachycardias, and in nine with cardiac rhabdomyomata. One child died from cardiac failure secondary to obstruction of the left ventricular outflow tract by a rhabdomyoma. Five of nine survivors showed resolution of Wolff-Parkinson-White syndrome on follow up. The accessory pathway was localised in nine patients from surface electrocardiograms: six children had left sided pathways and three had right sided pathways. 相似文献
27.
David AC Leggett Kenneth A Miles Benjamin B Kelley 《Journal of Medical Imaging and Radiation Oncology》1998,42(4):335-340
Five cases of cerebral glioma are presented here that illustrate the benefit of functional CT imaging of blood-brain barrier permeability and cerebral blood volume. Functional CT uses Patlak analysis of a single location dynamic sequence to extract physiological information that is useful clinically in the assessment of cerebral gliomas. Functional CT offers distinct advantages over other functional modalities including clearer delineation of tumour, tumour grading, measurement of tumour activity and monitoring response to therapy. 相似文献
28.
Gora Lô Amina Sow‐Sall Halimatou Diop‐Ndiaye Nokoa Chadia Ines Danty Mandiouba Moussa Thiam Fatou Diop Ousseynou Ndiaye Sokhna Bousso Gueye Sidy Mouhamed Seck Abou Abdallah Malick Dioura Moustapha Mbow Aïssatou Gaye‐Diallo Souleymane Mboup Coumba Touré‐Kâne 《Journal of medical virology》2016,88(3):461-465
29.
30.