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81.

Background  

To develop a sensitive and specific screening tool for knee and hip osteoarthritis in the general population of elderly people.  相似文献   
82.
The use of myocardial perfusion (82)Rb PET/CT studies continues to increase but its accuracy using database quantification methods for the diagnosis of coronary artery disease (CAD) has not been established. METHODS: A sex-independent normal database and criteria for abnormality for rest-stress (82)Rb PET/CT myocardial perfusion imaging were developed and validated by evaluation of 281 patients (136 females: mean age +/- SD, 63.3 +/- 13.3 y; 145 males: mean age +/- SD, 63.9 +/- 12.8 y) who underwent a rest-adenosine stress (82)Rb PET/CT study. These patients were divided into 3 groups: (a) healthy group: 30 patients, with <5% likelihood of CAD (low likelihood [LLK]) based on sequential Bayesian analysis; these patients were used to generate the normal distribution; (b) pilot group: 174 patients; these patients were used to determine the optimal criteria for detecting and localizing the perfusion abnormality; and (c) validation group: 76 patients (23 with LLK of CAD and 53 who underwent coronary angiography; these patients were used for prospective validation. RESULTS: Of the 53 patients who underwent coronary angiography, 8 had <50% stenosis and 45 patients had at least one stenosis > or =50% in one major artery. Fifteen patients had single-vessel disease, 17 had double-vessel disease, and 13 had triple-vessel disease. The prospective validation shows a normalcy rate of 78% (18/23) for global CAD. The analyses by individual arteries show a normalcy rate of 96% (22/23) for the left anterior descending coronary artery, 96% for the left circumflex coronary artery (22/23), and 100% for the right coronary artery (23/23). The overall sensitivity for detection of CAD (> or =50% stenosis) was 93% (42/45). The overall specificity for detection of the absence of CAD (< or =50% stenosis) was 75% (6/8). Also, the positive predictive value for global CAD was 95% (42/44), the negative predictive value was 67% (6/9), and the accuracy was 91% (48/53). CONCLUSION: The quantitative (82)Rb PET/CT database created and validated in this study is highly accurate for the detection and localization of CAD. Physicians should consider using the quantitative output of these algorithms as decision support tools to aid with image interpretation.  相似文献   
83.
84.
CD24 expression on human keratinocytes   总被引:4,自引:0,他引:4  
Abstract: CD24 or Nectadrin is a cell surface glycoprotein expressed in pre-B lymphocytes, T lymphocytes, neurons, muscle cells and carcinoma cells. Its function is not completely known, but it has been suggested that it is involved in cell adhesion and signalling. CD24 has recently been identified as the human molecule homologous to the murine heat-stable antigen (HSA). HSA is expressed by murine keratinocytes and delivers costimulatory signals in T-cell activation. Long-term cultures of normal human keratinocytes (HKC) were obtained from skin of human female breast sections and either left untreated or were treated with phorbol-12-myristate-13-acetate (PMA) at 10–100 ng/ml, calcium 0.5–2 mM or IFN-γ 100–1000 U/ml, for 24–48 h. Using RT-PCR and flow cytometry we showed that HKC express low levels of CD24 even under basal conditions, and the treatment with calcium, PMA or IFN-γ increased levels of CD24 mRNA and protein. To the best of our knowledge, this is the first report to measure CD24 expression and production by cultured HKC in basal conditions and after stimulation. Further studies are needed to determine biological and therapeutical relevance of these findings.  相似文献   
85.
86.
Rib fractures in children: a marker of severe trauma   总被引:4,自引:0,他引:4  
The early recognition of life-threatening injury is paramount to the prompt initiation of appropriate care. This study assesses the importance of multiple rib fractures as a marker of severe injury in children. We analyzed physiologic, etiologic, and injury data for 2,080 children with blunt or penetrating trauma aged 0-14 years consecutively admitted to a Level I pediatric trauma center. Analysis of variance, Student's t-test, and the Chi-square test of independence were used to test for differences between children with rib fractures and other children. Probability of survival was modeled using stepwise logistic regression. There were 14 deaths among 33 children with rib fractures, a mortality rate of 42%. Child abuse accounted for 63% of the injuries to children less than 3 years old, while pedestrian injuries predominated among older children. Children with rib fractures were significantly more severely injured than children with blunt or penetrating trauma but without rib fractures. When compared to children without rib fractures, children with rib fractures had a higher mortality rate, but no statistically significant difference in morbidity. The mortality rate for the 18 children with both rib fractures and head injury was 71%. A logistic model with variables measuring severity of head injury and number of ribs fractured correctly predicted survival in more than 85% of children with thoracic trauma. Although rib fractures are rare injuries in childhood, they are associated with a high risk of death. The risk of mortality increases with the number of ribs fractured. The combination of rib fractures and head injury was usually fatal.  相似文献   
87.
88.
We present a new case of Pilomatrix Carcinoma after having review the 22 cases previously published. The tumor arisen in a 74 years old male, in the left preauricular region. The lesion was excised with wide margins. A year after there is not any evidence of recurrence or metastases.  相似文献   
89.
The aim of this study was to evaluate the rate of alcohol recidivism after orthotopic liver transplantation (OLT) for alcoholic liver disease (ALD) and its influence on the allograft and patient survival, as well as the development of comorbidities and de novo cancers. The study was performed on 54 subjects previously analyzed and transplanted in our center for ALD, whose follow-up was prolonged to a mean of 99.2 (SD 31.7) months (range, 14-155). Medical records were reviewed, and data on alcohol consumption, therapeutic compliance, graft evolution, rejection, infections, comorbidities, rates of de novo malignancies and other clinical events, and survival were collected. Comparisons between groups were performed by the Fisher's exact test, and survival was assessed by the Kaplan-Meier method. Survival curves were compared using the Mantel-Cox statistic. The risk of death resulting from alcohol recidivism was analyzed with a Cox proportional hazards model. Fourteen patients who underwent transplantation for ALD (25.9%) returned to alcohol use between 5.0 and 86.9 months after OLT (median, 47.5). There was no significant association between the presence or absence of alcohol recidivism and the occurrence of graft rejection, infections, associated comorbidities after OLT, or compliance. The 5- and 10-year survival rates for patients with alcohol recidivism were 92.9% and 45.1%, respectively, compared with 92.4% and 85.5%, respectively, for patients without alcohol recidivism. These figures show significantly lower survival rates in recidivistic patients after 10 years (P < 0.01, Mantel-Cox). The fact that patients who resumed alcohol consumption have a worse 10-year survival rate might be attributed to a higher frequency of deaths, primarily from cancer and cardiovascular events.  相似文献   
90.
OBJECTIVES: This research studied the correlates of health insurance status among three major subpopulations (Mexican, Puerto Rican, and Cuban) of adult (ages of 20 to 64) Latino women. METHODS: Data from the Hispanic Health and Nutrition Examination Survey (HHANES), 1982-1984, were examined to determine the percentages of health insurance coverage among the sample populations and to assess the relationship between access to coverage and selected sociodemographic employment/income, ancestry, and acculturation variables. RESULTS: Variations in health insurance coverage existed by Latina subpopulation. While Puerto Rican women had the highest percentage of any health insurance coverage, Mexican-origin women (particularly those 50 to 64 years old) had the lowest. For all three Latina groups, health insurance coverage was greater among those who reported a family income above the poverty level than among those whose income fell below the poverty level; employment location, acculturation variables, and ancestry were also related to coverage. CONCLUSIONS: Eligibility requirements, particularly for Mexican-and Cuban-origin women, need to be streamlined, and innovative health insurance programs need to be developed to increase access of Latinas to health insurance.  相似文献   
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