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61.
BACKGROUND: 18F-Fluorodeoxyglucose (FDG) assessments have provided clinically important information in cervical cancer. FDG studies can now be performed by both dedicated PET systems and by new-generation gamma cameras. Hybrid systems which consist of positron emission tomography (PET) or a gamma camera with X-ray for fusion of functional-anatomic data without changing the patient's position are now available. CASE: A woman with newly diagnosed cervical cancer underwent preoperative FDG studies using a hybrid gamma camera. In addition to the known primary tumor, FDG detected heretofore unidentified metastatic disease at the liver, bone, and para-aortic lymph nodes: the treatment approach was consequently altered to chemo- and radiotherapy. The fused images provided precise localization of the lesions, guiding bone biopsy and radiation field planning. CONCLUSION: When PET is unavailable, a modified gamma camera can provide clinically relevant data in patients with cervical cancer.  相似文献   
62.

OBJECTIVE

To garner Canadian physicians’ opinions on strategies to reduce hip fractures in long-term care (LTC) facilities, focusing on secondary prevention.

DESIGN

A cross-sectional survey using a mailed, self-administered, written questionnaire.

SETTING

Canada.

PARTICIPANTS

Family physician members of the Ontario Long-Term Care Association (n = 165) and all actively practising geriatricians registered in the Canadian Medical Directory (n = 81).

MAIN OUTCOME MEASURES

The strength of recommendations for fracture-reduction strategies in LTC and barriers to implementing these strategies.

RESULTS

Of the 246 physicians sent the questionnaire, 25 declined study materials and were excluded. Of the 221 remaining, 120 responded for a response rate of 54%. About two-thirds of respondents were family physicians (78 of 120) and the rest were mostly geriatricians. Most respondents strongly recommended the following secondary prevention strategies for use in LTC after hip fracture: calcium, vitamin D, oral aminobisphosphonates, physical therapy, and environmental modification (such as handrails). Most respondents either did not recommend or recommended limited use of etidronate, intravenous bisphosphonates, calcitonin, raloxifene, testosterone (for hypogonadal men), and teriparatide. Postmenopausal hormone therapy was discouraged or not recommended by most respondents. Support was mixed for the use of hip protectors, B vitamins, and folate. Barriers to implementation identified by most respondents included a lack of strong evidence of hip fracture reduction (for B vitamins and folate, cyclic etidronate, and testosterone), side effects (for postmenopausal hormone therapy), poor compliance (for hip protectors), and expense (for intravenous bisphosphonates and teriparatide). Some respondents cited side effects or poor compliance as barriers to using calcium and potent oral bisphosphonates.

CONCLUSION

Canadian physicians favour the use of calcium, vitamin D, potent oral bisphosphonates, physical therapy, and evironmental modifications for LTC residents after hip fracture. Further study at the clinical and administrative levels is required to find ways to overcome the specific barriers to implementation and effectiveness of these interventions.  相似文献   
63.
OBJECTS: The relationship between increased central venous pressure (CVP) and development of hydrocephalus has been extensively discussed in the neuropediatric literature. However, the possibility of a direct connection has not been systematically examined. The purpose of this prospective study was to examine whether there was a correlation between elevated CVP and hydrocephalus in children undergoing cardiac catheterization. METHODS: We used cardiac catheterization to measure the right atrial and superior vena caval pressure in 37 children (mean age 30 months) with congenital heart malformations. The children had CVP higher than normal (mean 10.2+/-3.1 mmHg, range 4-18). To evaluate the size of the lateral and fourth ventricles, we performed CT scans of the brain on each child. Abnormal scans were found in 15/37 children, showing brain atrophy (12/37), ventriculomegaly (3/37), and focal infarction (1/37). Cerebral atrophy was more likely to occur in young children (P<0.001). The average head circumference among these children was less than 2SD below the mean for healthy children of comparable ages. Using a correlation coefficient regression model, no relationship was found between CVP and ventricular diameters or head circumference. CONCLUSIONS: These results argue against the hypothesis that mild to moderately elevated venous pressure is involved in the mechanism and development of pediatric hydrocephalus.  相似文献   
64.
The non-neuronopathic form Gaucher disease, the most prevalent lysosomal storage disorder, is marked by tremendous phenotypic heterogeneity; cardio-pulmonary involvement is distinctly rare except in the most severely affected patients. With the advent of enzyme replacement therapy, most symptomatic patients will not suffer from lung disease. However, because of concern about pulmonary hypertension among adult patients exposed to enzyme replacement therapy, echocardiography has been recommended as an early warning system for routine follow-up of all patients, including children. The purpose of this study was to review the results of more than a decade of echocardiographic findings in children followed semi-annually in a large referral clinic in order to ascertain whether echocardiography as an early signal of pulmonary hypertension in children is appropriate. 330 echocardiographic examinations were performed in 71 children (276 patient follow-up years). Only four patients receiving enzyme therapy each had a single abnormal examination that upon repeat examination six months later reverted to within normal limits. There were no abnormal results among the untreated patients. Therefore, we feel comfortable with rescinding our recommendation with regard to routine echocardiographic examinations in children. At the present time we believe that a baseline examination to rule out abnormalities would be sufficient.  相似文献   
65.
PROBLEM: Abnormal immune activation has been suggested as a contributor to the development of preeclampsia. We hypothesized that intact interleukin (IL)-12 directly, or through its main mediator, interferon (IFN)-γ, contributes to the altered immune response observed in preeclampsia. METHOD OF STUDY: Plasma samples were collected from 20 patients with preeclampsia and 20 normotensive patients with uncomplicated pregnancies who were matched with the preeclamptic patients by age, gestational age, and parity. Samples were collected before the onset of labor, induction, or medical intervention. The samples were assayed for IL-12 and IFN-γ by specific enzyme-linked immunoassays. RESULTS: IL-12 was detected in 35% of the preeclamptic patients and in 5% of the patients with normal pregnancies (P < 0.01). The detection rate and mean concentration of IFN-γ were comparable in both groups. CONCLUSION: Intact plasma IL-12 is detected more frequently in preeclamptic patients, suggesting the involvement of this cytokine in the enhanced immune response observed in preeclampsia.  相似文献   
66.
67.
Abstract Two siblings, a 12-year-old girl and a 7-year-old boy, had recurrent episodes of haemolyticuraemic syndrome/thrombotic thrombocytopenic purpura, manifested mainly by thrombocytopenia and micro-angiopathic haemolytic anaemia. During 11 years of follow up the girl responded only to steroids, whereas many other therapeutic modalities were ineffective. Following treatment with low dose danazol relapses became fewer and of diminished severity and completely subsided after 6 months. The boy started his illness with signs of haemolytic uraemic syndrome and later developed neurological manifestations. During a 6 year follow up he responded only to plasma exchange. Althouth chronic thrombocytopenia persisted during the past 3 years, the boy's clinical condition improved.Conclusion A family with two children with recurrent episodes of thrombotic thrombocytopenic purpura is described. In one child danazol could have had a beneficial effect.  相似文献   
68.
Objective: The decision to treat initial approximal carious lesions is based mainly on interpretation of bitewing radiographs. In a previous report, it was shown that artificial approximal lesions of uniform size are more readily detected on radiographs in premolars than in molars. The objective of the present study was to compare the ability to evaluate the depth of similar size artificial lesions on radiographs and reach decisions concerning treatment, in premolars and molars.

Method: Clinicians were asked to evaluate on radiographs, the size of in vitro prepared artificial lesions, and decide at which point they would perform a restoration.

Results: Significant differences were found in the evaluation of lesion depth between different tooth surfaces. The interaction between lesion depth and tooth surface originated from the examiners' trend to score same size lesions as penetrating deeper into the tooth in premolars than in molars. The probability of the examiners to decide on restorative treatment in shallow lesions (0.25 mm, 0.50 mm) was higher in premolars than in molars.

Conclusions: The findings suggest that clinicians evaluate initial lesions as being deeper and more prone to treatment in premolars than in molars.  相似文献   

69.
The primary aim of this study is to explore how school-related variables predict high school students' subjective judgements of school violence. Using a nationally representative sample (Israel) of 3,518 high school-aged youth, this study tested the hypotheses that (a) students' personal fear of attending school due to violence and (b) students' assessment of a school violence problem are best understood as separate conceptual constructs. The findings support the proposition that student fear of attending school and assessments of school violence as a problem are influenced by different types of school-related variables. Student fear of attending school due to violence was directly related to experiences of personal victimization by students and school staff. In contrast with fear, students'judgements of their schools' overall violence problem were directly associated with the variables of school climate, observed risk behaviors, and personal victimization. Implications for policy, theory, and future research are highlighted.  相似文献   
70.
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