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91.
We report on the development of a monitoring test for recurrent breast cancer, using metabolite-profiling methods. Using a combination of nuclear magnetic resonance (NMR) and two-dimensional gas chromatography-mass spectrometry (GC×GC-MS) methods, we analyzed the metabolite profiles of 257 retrospective serial serum samples from 56 previously diagnosed and surgically treated breast cancer patients. One hundred sixteen of the serial samples were from 20 patients with recurrent breast cancer, and 141 samples were from 36 patients with no clinical evidence of the disease during ~6 years of sample collection. NMR and GC×GC-MS data were analyzed by multivariate statistical methods to compare identified metabolite signals between the recurrence samples and those with no evidence of disease. Eleven metabolite markers (seven from NMR and four from GC×GC-MS) were shortlisted from an analysis of all patient samples by using logistic regression and 5-fold cross-validation. A partial least squares discriminant analysis model built using these markers with leave-one-out cross-validation provided a sensitivity of 86% and a specificity of 84% (area under the receiver operating characteristic curve = 0.88). Strikingly, 55% of the patients could be correctly predicted to have recurrence 13 months (on average) before the recurrence was clinically diagnosed, representing a large improvement over the current breast cancer-monitoring assay CA 27.29. To the best of our knowledge, this is the first study to develop and prevalidate a prediction model for early detection of recurrent breast cancer based on metabolic profiles. In particular, the combination of two advanced analytical methods, NMR and MS, provides a powerful approach for the early detection of recurrent breast cancer.  相似文献   
92.
The goal of this study was to determine the normal levels of CD4+ T lymphocytes in healthy individuals who were HIV seronegative in the Manya and Yilo Krobo Districts of Ghana's Eastern Region. This enabled comparisons with normal CD4 count ranges established by the World Health Organization (WHO). The study population consisted of 249 HIV-seronegative clients from a mobile free Voluntary Counseling and Testing (VCT) service in communities of the two districts during a one-month period. The mean CD4 count of these individuals was 1067 cells/microl with women demonstrating higher baseline CD4 counts than men. This study found a WHO comparable HIV seronegative baseline CD4 count as well as gender-based differences in the CD4 count and CD4/CD8 ratio. Establishment of the adult baseline for the country provides important demographic data and indicates the appropriateness of current global treatment guidelines with regards to CD4 levels in Ghana.  相似文献   
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Neonates and infants are relatively protected from clinical malaria, but the mechanism of this protection is not well understood. Maternally derived antibodies are commonly believed to provide protection against many infectious diseases, including malaria, for periods of up to 6-9 months but several recent epidemiological studies have produced conflicting results regarding a protective role of passively acquired antimalarial antibodies. In this article, we review the epidemiological evidence for resistance of young infants to malaria, summarize the data on antimalarial antibody levels and specificity and their association with protection from malaria infection or clinical disease, and explore alternative explanations for resistance to malaria in infants.  相似文献   
95.
The fluoroquinolone antibiotics sparfloxacin, grepafloxacin, gatifloxacin, and levofloxacin have been reported to cause torsades de pointes. Pre-existing risk factors increase vulnerability to this life-threatening arrhythmia. In a 65-year-old woman with a history of hypertension, coronary artery disease, systemic lupus erythematosus, and osteomyelitis, QTc interval prolongation (605 ms) and torsades de pointes developed after the initiation of levofloxacin, 250 mg intravenously once daily. The patient was hypokalemic and mildly hypomagnesemic before the initiation of levofloxacin and at the time of occurrence of torsades de pointes. The QTc interval decreased to 399 ms within hours of discontinuation of the levofloxacin, after which she had no further arrhythmias. In this and the majority of other published cases of fluoroquinolone-associated torsades de pointes, patients had at least 1 risk factor for the arrhythmia, and most had multiple risk factors. Fluoroquinolone antibiotics should be avoided whenever possible in patients with pre-existing risk factors for torsades de pointes.  相似文献   
96.
ObjectivesTo describe the rate of do-not-resuscitate (DNR) and do-not-hospitalize (DNH) orders among residents newly admitted into long-term care homes. We also assessed the association between DNR and DNH orders with hospital admissions, deaths in hospital, and survival.DesignA retrospective cohort study.Setting and participantsAdmissions in all 640 publicly funded long-term care homes in Ontario, Canada, between January 1, 2010 and March 1, 2012 (n = 49,390).MeasuresWe examined if a DNR and/or DNH was recorded on resident's admission assessment. All residents were followed until death, discharge, or end of study to ascertain rates of several outcomes, including death and hospitalization, controlling for resident characteristics.ResultsUpon admission, 60.7% of residents were recorded to have a DNR and 14.8% a DNH order. Those who were older, female, widowed, lived in rural facilities, lived in higher income neighborhoods prior to entry, had higher health instability or cognitive impairment, and spoke English or French were more likely to receive a DNR or DNH. Survival time was only slightly shorter for those with a DNR and DNH with a mean of 145 and 133 days, respectively, vs 160 and 153 days for those without a DNR and DNH. After controlling for age, sex, rurality, neighborhood income, marital status, health instability, cognitive performance score, and multimorbidity, DNR and DNH were associated with an odds ratio of 0.57 [95% confidence interval (CI) 0.53-0.62] and 0.41 (95% CI 0.37-0.46) for dying in hospital, respectively. Those with a DNR and DNH, after adjustment, had an incidence rate ratio of 0.87 (95% CI 0.83-0.90) and 0.70 (95% CI 0.67-0.73), respectively, days spent in hospital.Conclusions and implicationsThis study outlines identifiable factors influencing whether residents have a DNR and/or DNH order upon admission. Both orders led to lower rates, but not absolute avoidance, of hospitalizations near and at death.  相似文献   
97.
Quality health care is a fundamental human right, which is enshrined in several international and domestic legislative instruments. In the Ghanaian context, there are reports that adults with disabilities encounter barriers in their attempts to access health care. However, scholarly attention is yet to explore the perspectives of young people and adolescents with disabilities. Therefore, this quantitative study was conducted from the perspective of critical disability studies, where young deaf adolescents (YDAs) were regarded as right bearers, and where they shared their perspectives on health accessibility decisions, barriers, and needs. Sixty‐seven participants, made up of 44 male and 23 female students, took part in this quantitative study. Although many YDAs who took part in this study indicated that it was not difficult to access health facilities, they claim to have encountered communication barriers. Sign language interpreters in health facilities and introduction of sign language courses in health training institutions to improve communication between health professionals and deaf patients have been suggested as ways of addressing the barriers faced by YDAs in Ghana.  相似文献   
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99.

Background  

Ghana has not conducted a national tuberculin survey or tuberculosis prevalence survey since the establishment of the National Tuberculosis Control Programme. The primary objective of this study was therefore to determine the prevalence of tuberculin skin sensitivity in Ghanaian school children aged 6-10 years in 8 out of 10 regions of Ghana between 2004 and 2006.  相似文献   
100.

Background  

This paper draws from research completed in 2007 to assess the effect of the Department of Health, England, Code of Practice for the international recruitment of health professionals.  相似文献   
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