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101.
PGE1 accelerates thrombolysis by tissue plasminogen activator   总被引:14,自引:0,他引:14  
Vaughan  DE; Plavin  SR; Schafer  AI; Loscalzo  J 《Blood》1989,73(5):1213-1217
Platelets are an active element in the generation of thrombus and may influence rates of thrombolysis during the administration of plasminogen activators. To assess the potential importance of platelet aggregation in the thrombolytic response to plasminogen activators, we measured rates of thrombolysis induced by tissue plasminogen activator in the presence and absence of a coinfusion of prostaglandin E1 in a rabbit jugular vein model of thrombosis. Rates of lysis were quantified by measuring the half-time for lysis of the thrombus. At all concentrations of tissue plasminogen activator used, prostaglandin E1 markedly reduced the half-time for clot lysis and enhanced somewhat the overall extent of thrombolysis, without affecting significantly either the degree of fibrinogen depletion or the animals' mean arterial pressures. These effects on thrombolytic efficacy were accompanied by ex vivo evidence of platelet inhibition. These data suggest that the antiplatelet prostaglandin E1 may be a very useful adjunctive agent in thrombolytic therapy primarily by virtue of the significant improvement in the rate of thrombolysis that its use affords.  相似文献   
102.

Background

In addition to joint destruction, there is often also a loss of rotator cuff function in rheumatism patients. Thus, joint replacement alone using an anatomical prosthesis is unable to achieve satisfactory results. A half-linked inverse prosthesis, on the other hand, achieves improved function even in the presence of non-functioning rotator cuffs.

Patients and Methods

Of 157 shoulder prostheses that were followed up, 21 had been implanted in patients with rheumatoid arthritis. An anatomical endoprosthesis was implanted in 15 cases and an inversed endoprosthesis in six cases (average age 55.5/66.6 years).

Results

The Constant score improved from 23 to 65 points for the anatomical prosthesis and from 15 to 67 points for the inversed endoprosthesis. An analogous improvement was also noted for mobility, strength and pain relief.

Conclusion

The results of anatomical prostheses depend substantially on the extent of damage to the rotator cuff. Implantation of a semi-constrained inversed prosthesis provides a solution for severely damaged joints since it has a fixed centre of rotation. One prerequisite of success, however, is a sufficient bone stock in the glenoid region. The indication for bipolar prostheses, in contrast, is particularly strong when implantation of an inverse prosthesis is no longer possible.  相似文献   
103.
Due to the reduction of air change rates in low-energy houses, the contribution to indoor air quality of volatile organic compounds (VOCs) emitting from oriented strand boards (OSB) has become increasingly important. The aim of this study was to evaluate sensory irritations, pulmonary effects and odor annoyance of emissions from OSB in healthy human volunteers compared to clean air. Twenty-four healthy non-smokers were exposed to clean air and OSB emissions for 2 h under controlled conditions in a 48 m(3) test chamber at three different time points: to fresh OSB panels and to the same panels after open storage for 2 and 8 weeks. Chemosensory irritation, exhaled nitric oxide (NO) concentration, eye blink frequency, lung function and subjective perception of irritation of eyes, nose and throat were examined before, during and after exposure. Additionally, olfactory perception was investigated. Total VOC exposure concentrations reached 8.9 ± 0.8 mg/m(3) for the fresh OSB panels. Emissions consisted predominantly of α-pinene, Δ(3)-carene and hexanal. Two-hour exposure to high VOC concentrations revealed no irritating or pulmonary effects. All the subjective ratings of discomfort were at a low level and the medians did not exceed the expression 'hardly at all.' Only the ratings for smell of emissions increased significantly during exposure in comparison to clean air. In conclusion, exposure of healthy volunteers to OSB emissions did not elicit sensory irritations or pulmonary effects up to a VOC concentration of about 9 mg/m(3). Sensory intensity of OSB emissions in the chamber air was rated as 'neutral to pleasant.'  相似文献   
104.

INTRODUCTION

Early carotid endarterectomy (CEA) in symptomatic patients may prevent repeat cerebral events. This study investigates the relationship between waiting time for CEA and the incidence of repeat cerebral events prior to surgery in symptomatic patients.

PATIENTS AND METHODS

A prospective database of consecutive patients undergoing CEA between January 2002 and December 2006 was reviewed. Repeat event rates prior to surgery were calculated using Kaplan–Meier analysis and predictive factors identified using Cox regression analysis.

RESULTS

A total of 118 patients underwent CEA for non-disabling stroke, TIA and amaurosis fugax. Repeat cerebral events occurred in 34 of 118 (29%) patients at a median 51 days (range, 2–360 days) after the first event. The estimated risk of repeat events was 2% at 7 days and 9% at 1 month after first event (Kaplan–Meier survival analysis). Age (HR 1.059; 95% CI 1.014–1.106; P = 0.009] was identified as a predictor of repeat events. Patients underwent surgery at median 97 days (range, 7–621 days) after the first event. Eleven of 60 (18%) patients waiting ≤?97 days for surgery and 23 of 58 (40%) patients waiting >?97 days had repeat events. (P = 0.011, chi-squared test).

CONCLUSIONS

Delays in surgery should be reduced in order to minimise repeat cerebral events in patients with symptomatic carotid stenosis, particularly in the elderly population.  相似文献   
105.
India has a high prevalence of diabetes mellitus and the numbers are increasing at an alarming rate. In India alone, diabetes is expected to increase from 40.6 million in 2006 to 79.4 million by 2030. Studies have shown that the prevalence of diabetes in urban Indian adults is about 12.1%, the onset of which is about a decade earlier than their western counterparts and the prevalence of Type 2 diabetes is 4–6 times higher in urban than in rural areas. The risk factors peculiar for developing diabetes among Indians include high familial aggregation, central obesity, insulin resistance and life style changes due to urbanization. Screening for gestational diabetes and impaired glucose tolerance among pregnant women provides a scope for primary prevention of the disease in mothers as well as in their children. The problems of obesity and impaired glucose tolerance (IGT) (important predisposing factors) are not confined to adults alone but children are also increasingly getting affected. Most long standing macro and micro vascular complications are also more common among Indian diabetics as compared to other races and ethnic groups. A strong familial clustering of diabetic nephropathy among Indian Type 2 diabetics has also been noted. Clustering of cardiovascular risk factor like Syndrome X is common among urban Indians. The rising incidence of diabetes and its complications are going to pose a grave health care burden on our country. Timely effective interventions/measures and screening tests for complications at the time of diagnosis becomes imperative not only for early detection, but also to prevent progression to end stage disease. Screening for gestational diabetes among pregnant women would also go a long way in primary prevention of the disease. Life style changes/interventions and drugs like rosiglitazone are the current strategies that can prevent and/or delay the onset of diabetes. Simple interventional strategies like “Eat less, Eat on time and Walk more” can go a long way in preventing these chronic disorders among present as well as in the future generations.  相似文献   
106.

Background

Disorders of visual acuity are known to affect the learning abilities of school children. Various authors have reported varying prevalence in India and abroad.

Methods

A rapid, community based survey was conducted to assess the prevalence of disorders of visual acuity among adolescent school children in three schools in Pune Cantonment. A sample of 236 children studying in six sections were examined after random selection by a two stage sampling technique ensuring representation to each of the classes. Visual acuity was assessed for all the children available in the selected section on the date of survey. A questionnaire based study of the knowledge and attitude of the parents of the 50 affected children was also conducted.

Result

50 children (25 males and 25 females) were found to have errors of refraction, resulting in prevalence rate of 21.19% with confidence intervals of 15.97% to 26.40%.

Conclusion

The study highlights significantly high prevalence of uncorrected errors of visual acuity among adolescent school children as well as the need for instituting IEC activities aimed at improving the general lack of appreciation of the seriousness of the problem by the parents and consequent neglect of urgent corrective measures.Key Words: Visual defects, Adolescent school children  相似文献   
107.
108.
109.
Fabry disease is a disorder of alpha-D-galactosyl-containing glycolipids resulting from a deficiency of alpha-galactosidase A. Patients have a poorly understood vascular dysregulation. We hypothesized that disease-related perturbation by using enzyme replacement therapy in the murine model of Fabry disease would provide insight into abnormal biological processes in Fabry disease. Gene expression analyses of the heart, aorta, and liver of male alpha-galactosidase A knockout mice 28 weeks of age were compared with that of WT mice. Microarray analyses were performed before and after six weekly injections of alpha-galactosidase A. Alteration of Rpgrip1 ranked highest statistically in all three organs when knockout mice were compared with WT, and its splice variants responded in a unique way to alpha-galactosidase A. Enzyme replacement therapy tended to not only normalize gene expression, e.g., reduce the overexpression of securin, but also specifically modified gene expression in each tissue examined. Following multiple comparison analysis, gene expression correlation graphs were constructed, and a priori hypotheses were examined by using structural equation modeling. This systems biology approach demonstrated multiple and complex parallel cellular abnormalities in Fabry disease. These abnormalities form the basis for informed, in a Bayesian sense, sequential, hypothesis-driven research that can be subsequently tested experimentally.  相似文献   
110.
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