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Background:

Associations between medical conditions and pancreatic cancer risk are controversial and are thus evaluated in a study conducted during 1994–1998 in Minnesota.

Methods:

Cases (n=215) were ascertained from hospitals in the metropolitan area of the Twin Cities and the Mayo Clinic. Controls (n=676) were randomly selected from the general population and frequency matched to cases by age and sex. The history of medical conditions was gathered with a questionnaire during in-person interviews. Odds ratios (OR) and 95% confidence intervals (95% CI) were estimated using unconditional logistic regression.

Results:

After adjustment for confounders, subjects who had cholecystectomy or gallstones experienced a significantly higher risk of pancreatic cancer than those who did not (OR (95% CI): 2.11 (1.32–3.35) for cholecystectomy and 1.97 (1.23–3.12) for gallstones), whereas opposite results were observed for tonsillectomy (0.67 (0.48–0.94)). Increased risk associated with cholecystectomy was the greatest when it occurred ⩽2 years before the cancer diagnosis (5.93 (2.36–15.7)) but remained statistically significant when that interval was ⩾20 years (2.27 (1.16–4.32)).

Conclusions:

Cholecystectomy, gallstones, and tonsillectomy were associated with an altered risk of pancreatic cancer. Our study suggests that cholecystectomy increased risk but reverse causality may partially account for high risk associated with recent cholecystectomy.  相似文献   
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目的探讨脂肪来源干细胞表达的CD44,可以被糖基化技术进行修饰,成为造血干细胞E/L选择素配体(HCELL),进而可有效的骨髓归巢并原位分化成骨。 方法应用α-1,3-唾液盐藻糖酶:FTV以及其底物GDP-海藻糖处理人脂肪来源干细胞,使该细胞表面CD44分子糖基化为HCELL,检测其增殖、分化等细胞生物学特性。平行平板流动腔试验以及免疫荧光染色验证其小鼠体内归巢及成骨能力。 结果α-1,3-岩藻糖基化的hASC在不损害细胞活力的情况下表达HCELL,能够诱导血管内皮细胞表面E-选择素与其结合,并在剪切力条件下,使hASCs与内皮E-选择素产生强大的滚动粘附效应,促进hASCs迁移到骨髓中,并在小鼠骨髓中产生人骨样细胞。 结论本研究证明糖基化技术能够增强干细胞的骨髓归巢能力,且不对干细胞自身细胞活性产生负向作用。  相似文献   
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Objectives: to evaluate the diagnostic value of clinical symptoms and signs in enteric fever and to propose a clinical diagnostic criterion. Design: Prospective observational study Setting: Kathmandu Medical College, Teaching Hospital, Kathmandu, Nepal Materials and methods: febrile patients with clinical diagnosis of enteric fever were included in the study with the aim of confirming diagnosis with blood culture, or bone marrow culture and evaluating the diagnostic accuracy of various clinical signs and symptoms. Results: 64% of the clinically diagnosed cases had blood/ bone marrow culture positive. The diagnostic accuracy of the various symptoms and signs excluding fever was between 42%-75.5%. Majority of the symptom and sign did not have very high diagnostic accuracy. Hence a diagnostic criterion was proposed and clinical features with diagnostic accuracy more than 50% were taken into consideration. Major criteria included fever with diagnostic accuracy of 64%, headache with accuracy of 75.5% and relative bradycardia with an accuracy of 66%. Minor criteria included vomiting, diarrhoea, Splenomegaly, chills and abdominal pain /discomfort with diagnostic accuracy of 57%, 55%, 55%, 53% and 51% respectively. Finally after combination of various major and minor criteria a final diagnostic criterion was proposed having an accuracy of 66% and including both major and minor clinical symptom and sign. Conclusion: clinical diagnosis of enteric fever will be very helpful in a country like ours. Though none of the clinical symptoms and sign have very high diagnostic accuracy a diagnostic criteria may be helpful. Criteria including both major and minor signs and symptoms would be the most appropriate diagnostic tool as it includes the important abdominal symptoms and signs of enteric fever. Key words: enteric fever, clinical features, diagnostic criteria.  相似文献   
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Introduction: Perinatal mortality rate is a sensitive indicator of quality of care provided to women in pregnancy, at and after child birth and to the newborns in the first week of life. Regular perinatal audit would help in identifying all the factors that play a role in causing perinatal deaths and thus help in appropriate interventions to reduce avoidable perinatal deaths. Aims and objectives: This study was carried out to determine perinatal mortality rate (PMR) and the factors responsible for perinatal deaths at KMCTH in the two year period from November 2003 to October 2005 (Kartik 2060 B.S. to Ashoj 2062). Methodology: This is a prospective study of all the still births and early neonatal deaths in KMCTH during the two year period from November 2003 to October 2005. Details of each perinatal death were filled in the standard perinatal death audit forms of the Department of Pediatrics, KMCTH. Perinatal deaths were analyzed according to maternal characteristics like maternal age, parity, type of delivery and fetal characteristics like sex, birth weight and gestational age and classify neonatal deaths according to Wigglesworth's classification and comparison made with earlier similar study. Results: Out of the 1517 total births in the two year period, 22 were still births (SB) and 10 were early neonatal deaths (ENND). Out of the 22 SB, two were of < 1 kg in weight and out of 10 ENND, one was of <1 kg. Thus, perinatal mortality rate during the study period was 19.1 and extended perinatal mortality rate was 21.1 per 1000 births. The important causes of perinatal deaths were extreme prematurity, birth asphyxia, congenital anomalies and associated maternal factors like antepartum hemorrhage and most babies were of very low birth weight. According to Wigglesworth's classification, 43.8% of perinatal deaths were in Group I, 12.5% in Group II, 28.1% in Group III, 12.5% in Group IV and 12.5% in Group V. Discussion: The perinatal death audit done in KMCTH for 1 year period from September 2002 to August 2003 showed perinatal mortality rate of 30.7 and extended perinatal mortality rate of 47.9 per 1000 births. There has been a significant reduction in the perinatal mortality rate in the last 2 years at KMCTH. Main reasons for improvement in perinatal mortality rate were improvement in care of both the mothers and the newborns and the number of births have also increased significantly in the last 2 years without appropriate increase in perinatal deaths. Conclusion: Good and regular antenatal care, good care at the time of birth including appropriate and timely intervention and proper care of the sick neonates are important in reducing perinatal deaths. Prevention of preterm births, better care and monitoring during the intranatal period and intensive care of low birth weight babies would help in further reducing perinatal deaths. Key words: Perinatal mortality rate (PMR), still births, early neonatal death (ENND), Total perinatal death (PND).  相似文献   
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Obesity and other diet-related health conditions have received much attention in the public health literature over the past two decades. This study investigates the relationship between household food budget shares at different food outlets with diet quality and weight-related health outcomes in the United States. Our analysis used event-level food purchase data from the national household food acquisition and purchases survey (FoodAPS). We find that, after controlling for observables, food purchase location is significantly associated with diet quality and body mass index (BMI). Our findings indicate that larger food budget shares at convenience stores and restaurants are linked with poor diet quality based on the healthy eating index-2015 (HEI-2015) scores and higher BMI. We further explored potential heterogeneity on outcomes of interest across income groups. Results suggest heterogeneous effects may exist across income groups: low-income households, who spent a larger share of their food budget at convenience stores and fast-food restaurants are related to poor diet quality and more likely to be obese. Our findings will help improve understanding of the causes of diet-related health problems and may illuminate potential avenues of intervention to address obesity.  相似文献   
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