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291.
Only four independent double-blind studies have been reported of the effect of ascorbic acid regularly ingested in daily amounts more than 100 mg, in comparison with a placebo, in decreasing the incidence and integrated morbidity of the common cold for subjects exposed to cold viruses in the ordinary way and without colds when the test period began. A statistical analysis of these four studies leads to rejection of the null hypothesis that ascorbic acid has no more protective power than the placebo at the 99.86% level of confidence for the incidence of colds and the 99.9978% level of confidence for the integrated morbidity.  相似文献   
292.
BACKGROUND: This Phase II study assessed the response rate and toxicity profile of the combination CPT-11 and cisplatin administered weekly to patients with untreated, advanced adenocarcinoma of the stomach or the gastroesophageal junction. METHODS: Patients with histologic proof of adenocarcinoma of the stomach or the gastroesophageal junction with adequate liver, kidney, and bone marrow functions were treated with 65 mg/m(2) CPT-11 plus 30 mg/m(2) cisplatin, both administered intravenously 1 day per week for 4 consecutive weeks, followed by a recovery period of 2 consecutive weeks. The response rate, time to disease progression, survival, and toxic effects were analyzed. RESULTS: Thirty-six of 38 registered patients (95%) were assessable. The median number of 6-week cycles per patient was 2.5 (range, 1-7 6-week cycles). Four patients (11%) achieved a complete response, and 17 patients (47%) had a partial response for an overall response rate of 58%. The median time to progression of carcinoma was 24 weeks, and the median survival was 9 months (range, 1-23+ months). There was one treatment-related death. Major toxic effects included diarrhea, neutropenia, and fatigue. Ninety percent of all planned doses were delivered on time; however, 53 of 79 canceled or delayed weekly doses (66%) occurred in the third or fourth week of the therapy cycle. CONCLUSIONS: The combination of CPT-11 and cisplatin is active against gastric or gastroesophageal adenocarcinoma and needs to be studied further. A modification in doses and schedules may be warranted to make the regimen more tolerable to patients. The addition of other active drugs or radiation therapy to this regimen would be of interest.  相似文献   
293.
294.

Background/Aims

Improved data and methods are needed for modeling disease progression in Alzheimer’s disease (AD) for economic evaluation of treatments. The aim is to estimate prediction models for long-term AD progression and subsequently economic outcomes.

Methods

Three-year follow-up data on 435 patients treated with the cholinesterase inhibitor donepezil in clinical practise were analyzed. Regression models were estimated for long-term prediction of decline in cognitive function (ADAS-cog) and activities in daily living (ADL) ability, risk of institutionalization and costs of care.

Results

The cognitive deterioration was estimated at between 1.6 and 4 ADAS-cog points per every 6?months, increasing with disease severity. Cognitive function was an important predictor of ADL-ability, which itself was the most important predictor of the risk of institutionalization and costs of care. Combining all models in a cross-validation process generated accurate predictions of costs of care at each 6?months follow-up.

Conclusion

The proposed methods for representing AD progression and economic outcomes can be used in micro-simulation models for the economic evaluation of new treatments.  相似文献   
295.

Background

Esophageal atresia (EA) often leads to persistent symptoms and impaired respiratory function in adulthood. The role of peripheral airways in this impairment has not been previously investigated. Furthermore, asthma-like symptoms are common in these patients.

Purpose

The purpose of this study was to investigate pulmonary outcome, including possible peripheral airway dysfunction, perhaps missed by conventional pulmonary function tests and to see if the diagnosis asthma was accurate.

Methods

Twenty eight patients operated for EA in Gothenburg 1968–1983 answered a questionnaire regarding respiratory symptoms and underwent pulmonary function tests. Peripheral airway function was measured by multiple breath washout.

Results

22/28 (79%) patients had a history of respiratory symptoms. Abnormal peripheral airway function was found in 17 (61%) patients, while only 6 (21%) patients displayed values indicating central obstruction. Nine patients had restrictive disease. Airway hyperresponsiveness was frequent and associated with atopy and airway inflammation. However, respiratory symptoms or doctor-diagnosed asthma did not correlate with any specific lung function test abnormality.

Conclusion

Different lung function abnormalities are present in EA survivors, and peripheral airway disease is common. Classical asthma seems to be difficult to diagnose in this patient group. Given the high prevalence of respiratory morbidity, long-term follow-up of pulmonary function, including peripheral airway function, is warranted.  相似文献   
296.
297.
The endothelium serves as a selective barrier and controls the exchange of nutrients, hormones, and leukocytes between blood and tissues. Molecular mechanisms contributing to the pathogenesis of endothelial barrier dysfunction remain incompletely understood. Accumulating evidence implicates bone morphogenetic protein (BMP)-modulator BMPER as a key regulator in endothelial biology. Herein, we analyze the impact of BMPER in the control of endothelial barrier function. To assess the role of BMPER in vascular barrier function in mice, we measured the leakage of Evans blue dye from blood into interstitial lung tissue. BMPER+/? mice exhibited a significantly higher degree of vascular leak compared with wild-type siblings. In accordance with our in vivo observation, siRNA-based BMPER knockdown in human umbilical endothelial cells increased endothelial permeability measured by FITC-dextran passage in transwell assays. Mechanistically, BMPER knockdown reduced the expression of VE-cadherin, a pivotal component of endothelial adherens junctions. Conversely, recombinant human BMPER protein upregulated VE-cadherin protein levels and improved endothelial barrier function in transwell assays. The effects of BMPER knockdown on VE-cadherin expression and endothelial permeability were induced by enhanced BMP activity. Supporting this notion, activation of BMP4-Smad-Id1 signaling reduced VE-cadherin levels and impaired endothelial barrier function in vitro. In vivo, Evans blue dye accumulation was higher in the lungs of BMP4-treated C57BL/6 mice compared to controls indicating that BMP4 increased vascular permeability. High levels of BMPER antagonized BMP4-Smad5-Id1 signaling and prevented BMP4-induced downregulation of VE-cadherin and endothelial leakage, suggesting that BMPER exerts anti-BMP effects and restores endothelial barrier function. Taken together, this data demonstrates that BMPER-modulated BMP pathway activity regulates VE-cadherin expression and vascular barrier function.  相似文献   
298.
Maspin (SERPINB5), a serine proteinase inhibitor, was first identified as a potential tumor suppressor on the basis of its differential expression between normal mammary epithelial cells and human breast carcinoma cell lines. Recent studies have shown that maspin might be a prognostic tumor marker. Pancreatic ductal adenocarcinoma acquires maspin expression through hypomethylation of the maspin promoter. However, no study has investigated the prognostic significance of maspin expression in pancreatic ductal adenocarcinomas. In this study, we investigated maspin protein expression in a large series of 223 surgically resected pancreatic ductal adenocarcinomas using immunohistochemical staining and high throughput tissue microarrays. Maspin expression was correlated with postoperative survival and other clinicopathologic factors. Maspin was detected in 209 of these 223 (94% cases) pancreatic ductal adenocarcinomas including 39 (18% cases) focal (5-50% tumor cells) and 170 (76% cases) diffuse (>50% tumor cells). Fourteen (or 6% cases) pancreatic ductal adenocarcinomas did not show maspin expression by immunohistochemical staining (<5% tumor cells). Normal ductal epithelium is not labeled with maspin. Overexpression of maspin in pancreatic ductal adenocarcinoma is associated with worse postoperative survival especially in patients whose tumors exhibit diffuse expression of maspin. After adjusting other clinicopathologic factors, maspin expression remains to be an independent adverse prognosticator for postoperative survival. Maspin expression is not associated with patient age, gender, tumor size, tumor pathologic stage, lymph node status, and vascular invasion or perineural invasion. Nuclear labeling of maspin is associated with better tumor differentiation although this staining pattern is not associated with a better prognosis. In addition, maspin overexpression is also observed in 48% low-grade (grades 1a and 1b) pancreatic intraepithelial neoplasias (PanINs) and 78% high-grade (grades 2 and 3) PanINs, suggesting that maspin upregulation occurs early during the multi-step progression model of pancreatic ductal adenocarcinoma.  相似文献   
299.
Research on incompetent humans raises ethical challenges, especially when there is no direct benefit to these research subjects. Contemporary codes of research ethics typically require that such research must specifically serve to benefit the population to which the research subjects belong. The article critically examines this ??same-population condition??, raising issues of both interpretation and moral justification. Of particular concern is the risk that the way in which the condition is articulated and rationalized in effect disguises or downplays the instrumentalization of incompetent individuals.  相似文献   
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