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41.
Lymphocyte subpopulations were studied in 20 hypertransfused patients with beta-thalassaemia major, some of whom had been splenectomised. B-lymphocytes were normal but T-lymphocytes were decreased in all patients. The T-cell count was lower in the splenectomised patients than in the nonsplenectomised ones. In the former, the active rosette-forming lymphocytes were also diminished, but the difference was not significant. In all patients the percentage of null cells was greater and the activity of K-cells increased compared with controls.  相似文献   
42.
PURPOSE: Fenretinide (4-HPR) is a synthetic retinoid that has shown a preventive activity in prostate cancer animal models. EXPERIMENTAL DESIGN: We measured the changes in total and free prostate-specific antigen (PSA) and its association with insulin-like growth factor I (IGF-I) and IGFBP-3 levels after 1 year of treatment in 24 subjects given 4-HPR and 24 control subjects enrolled in a randomized bladder cancer prevention trial. RESULTS: No significant effect of 4-HPR was observed on total and free fraction of PSA levels. The median percentage [95 confidence interval (95% CI)] change for % free PSA and total PSA in the 4-HPR and the control group were, respectively, 7.6 (95% CI, -4.0 to 69.3) versus 5.1 (95% CI, -21.4 to 59.8) and -7.8 (95% CI, -18.2 to 52.5) versus -12.3 (95% CI, -44.6 to 9.6). However, in patients ages <60 years, there was a trend to an increase of total free PSA and % free PSA after treatment with 4-HPR that was different from a trend to a decrease in the control group (P = 0.002 and 0.052, respectively). The interaction between age and treatment was statistically significant on free PSA (P = 0.001). A similar pattern was noted with smoking status (P = 0.011 for the interaction on free PSA). No association was observed between PSA levels and IGF-I or IGFBP-3 levels. CONCLUSIONS: We conclude that 4-HPR has no significant effect on circulating PSA, but it increases significantly free PSA levels in subjects younger than 60 years and in nonsmokers. These effects might support an activity in prostate cancer prevention but further studies are required.  相似文献   
43.
Bivariate copula regression allows for the flexible combination of two arbitrary, continuous marginal distributions with regression effects being placed on potentially all parameters of the resulting bivariate joint response distribution. Motivated by the risk factors for adverse birth outcomes, many of which are dichotomous, we consider mixed binary-continuous responses that extend the bivariate continuous framework to the situation where one response variable is discrete (more precisely, binary) whereas the other response remains continuous. Utilizing the latent continuous representation of binary regression models, we implement a penalized likelihood–based approach for the resulting class of copula regression models and employ it in the context of modeling gestational age and the presence/absence of low birth weight. The analysis demonstrates the advantage of the flexible specification of regression impacts including nonlinear effects of continuous covariates and spatial effects. Our results imply that racial and spatial inequalities in the risk factors for infant mortality are even greater than previously suggested.  相似文献   
44.
ABSTRACT

Background: Depression is a pervasive psychological issue facing hemodialysis (HD) patients. Novel technology-based treatment strategies that deploy psychology-based interventions have not been the focus for therapy and few published studies exist. The aim of the current trial is to determine the feasibility and acceptability of an Internet-based positive psychological intervention in HD patients with comorbid depressive symptoms. Methods: HD patients (n = 14) with elevated symptoms of depression were enrolled in a single-arm pre-post trial with clinical assessments at baseline and immediately post intervention. Chairside during regularly scheduled HD treatment, patients utilized a web browser to complete online modules promoting skills for increasing positive emotion over a 5-week period using Apple IPads. Targeted skills included noting of daily positive events, gratitude, positive reappraisal, acts of kindness, and mindfulness/meditation. Results: Twelve of 14 patients completed the program for an 85.7% retention rate. Participants felt satisfied with each session and offered consistently positive feedback. On average, participants visited the website 3.5 times per week. Significant improvements were evident for depressive symptoms (15.3 vs. 10.9; = 0.04), as per the Center for Epidemiological Studies Depression Scale. Conclusions: An innovative Internet-based positive psychological intervention represents a feasible and useful therapeutic option for HD patients with depressive symptoms.  相似文献   
45.
Background: Vitamin D plays a pivotal role in calcium and phosphorus metabolism, also influencing bone tissue. Several studies have reported that vitamin D blood levels were significantly lower in people with obesity, probably due to its uptake by the adipose tissue. Clinical studies that investigated the changes of circulating levels of vitamin D following weight loss reported controversial data. A very low-calorie ketogenic diet is acknowledged as a reliable treatment to achieve a rapid weight loss. Therefore, we investigated the effect of weight loss, consequent to a very low-calorie ketogenic diet, on vitamin D blood concentrations. Methods: A cohort of 31 people with obesity underwent a very low-calorie ketogenic diet for 10–12 weeks. The serum concentrations of vitamin D, parathormone, calcium and phosphorous were measured before and after weight loss; they were compared to a control group of 20 non-obese, non-diabetic, age- and gender-matched persons. Results: Patients with obesity had a higher habitual intake of vitamin D than the control group (p < 0.05). However, the vitamin D blood levels of the obese group were significantly lower than those of the control group (p < 0.005) and they increased after weight loss (p < 0.001). At baseline, vitamin D blood concentrations of the persons with obesity were significantly correlated with both fat mass–kg (r = −0.40; p < 0.05) and body mass index (r = −0.47; p < 0.01). Following very low-calorie ketogenic diet, the change in vitamin D serum concentrations was correlated only with the change in fat mass–kg (r = −0.43; p < 0.01). Conclusion: This study confirmed that patients with obesity have lower vitamin D levels that normalize after significant weight loss, supporting the hypothesis that vitamin D is stored in the adipose tissue and released following weight loss.  相似文献   
46.
The aim of this research was to compare parental stress, coping strategies and social support perceived in families of children with low functioning autism (n = 8), high functioning autism (n = 10), Down syndrome (n = 12) and parents of typically developing children (n = 20). Specifically, the objective was to investigate which variables (coping strategies and perception of social support available) might better predict different stress outcomes in the four groups. Parents were asked to fill in three questionnaires: Parent Stress Index, Coping Orientation to Problems Experienced and Social Support Questionnaire. Significant differences among groups in all of the variables considered were found. These results suggest the advisability of fostering functional coping strategies and social support received in families of children with disabilities, and especially in those with children with low functioning autism.  相似文献   
47.
In the present study, we evaluated the relationship between nutritional status, disease stage and quality of life (QoL) in 100 patients recently diagnosed with gastric carcinoma. The patients' nutritional status was investigated with anthropometric, biochemical, inflammatory and functional variables; and we also evaluated the nutritional risk with the Nutritional Risk Screening 2002. Oncological staging was standard. QoL was evaluated using the Functional Assessment of Anorexia/Cachexia Therapy questionnaire. The statistical correlation between nutritional risk score (NRS) and oncological characteristics or QoL was evaluated using both univariable and multivariable analyses. Weight loss and reduction of food intake were the most frequent pathological nutritional indicators, while biochemical, inflammatory and functional variables were in the normal range. According to NRS, thirty-six patients were malnourished or at risk for malnutrition. Patients with NRS?≥?3 presented a significantly greater percentage of stage IV gastric cancer and pathological values of C-reactive protein, while no correlation was found with the site of tumour. NRS was negatively associated with QoL (P?相似文献   
48.
Enterobacter sakazakii is a pathogen of increasing medical concern, due to it being implicated in cases of meningitis, sepis, and necrotizing enterocolitis associated with the consumption of contaminated infant milk formula. At present, the method adopted by the Mexican food industry for the isolation and identification of E. sakazakii is based on the methodology of the United States Food and Drug Administration (FDA). However, this procedure is laborious and requires 7 days to obtain a confirmative result. The objective of this study was to determine the presence of E. sakazakii in two types of powdered infant milk formula, using an alternative method that requires less time and a smaller sample size than the FDA protocol. We adapted Leuschner's procedure by eliminating violet red bile glucose agar (VRBG) plates and instead adopting white light incubation to stimulate yellow pigment development. This allowed for isolation of E. sakazakii from powdered infant milk formula using a smaller sample and requiring only 5 days for analysis. Results showed that 92% of formula 1 and 32% of formula 2 was positive for E. sakazakii. The high contamination level of E. sakazakii suggests the need for monitoring hygienic conditions in the manufacturing plant and to assess the prevalence of E. sakazakii in powdered infant milk formulas sold in México.  相似文献   
49.
BACKGROUND: The aim of the study was to perform a comprehensive diagnostic evaluation of six popular, non-proprietary, indirect markers of liver fibrosis in a cohort of patients with chronic hepatitis C representing the full spectrum of disease severity. METHODS: A total of 167 consecutive, hepatitis C virus RNA positive, untreated patients with chronic hepatitis C were studied. Liver biopsy with histological evaluation and age/platelet index, aspartate aminotransferase/alanine aminotransferase ratio, aspartate aminotransferase to platelet ratio index, Bonacini's discriminant score, Forn's fibrosis index and FibroIndex were assessed in all patients. RESULTS: The area under the receiver operating characteristic curves of the six tests was always greater when performed to discriminate patients with METAVIR score F4 than when assessed to discriminate patients with METAVIR score > or =F2. At step-wise discriminant analysis the only indirect marker of fibrosis entered was FibroIndex, with the following correct classification of the patients: total=52.1, patients with scores F0-F1=62.2, patients with scores F2-F3=26.0 and patients with score F4=68.4. CONCLUSIONS: The ability to correctly classify patients using a panel of non-proprietary indirect markers of liver fibrosis is far from being ideal. Among them, FibroIndex appears to possess the best discriminating capacity. The simultaneous use of several indirect markers of liver fibrosis does not improve their diagnostic accuracy.  相似文献   
50.
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