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41.
Loss of intestinal lactase activity among adults could theoretically limit milk consumption and hence dietary availability of calcium during pregnancy. The present study sought to define, using breath hydrogen (H2) production as an index of incomplete carbohydrate absorption, the prevalence during pregnancy of lactose maldigestion of 360 mL of milk (18 g of lactose), and to determine whether lactose digestion improved as pregnancy advanced. The prevalence of lactose maldigestion among 114 pregnant women tested before the 15th week of gestation was 54%. By term, 44% of those originally classified as maldigesters had become digesters. There was a significant reduction in the four-hour sum of the changes in breath H2 concentration from the period before 15 weeks (116.6 +/- 9.6 ppm) to the time after 36 weeks (54.4 +/- 7.3 ppm; P less than .01). This apparent adaptive improvement in intestinal handling of milk lactose during gestation has implications for calcium intake and absorption.  相似文献   
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Hispanic student and faculty representation at US Schools of Public Health from 1975-1979 was investigated. Findings indicate a substantial underrepresentation of Hispanic students and faculty members at these schools. Hispanic public health graduates were found to be less likely than other graduates to receive an MPH degree or a doctorate. It appears that the University of Puerto Rico graduates one-half of all Hispanic graduates and employs two-thirds of all Hispanic public health faculty.  相似文献   
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Absolute lymphocyte count (ALC) >or=500 cells/microl at day 15 after autologous stem cell transplantation (ASCT) is a powerful independent, prognostic indicator for survival in multiple hematological malignancies. A limitation in these studies was the selection of a single time point (day 15 post-ASCT) as the only discriminator of clinical outcome in relation to ALC recovery. We hypothesized there is a continuous and not discrete relationship between ALC recovery and clinical outcome post-ASCT in NHL. Therefore, we analyzed 274 consecutive patients who underwent ASCT for NHL between 1987 and 2001. The primary end point was to assess the impact of the kinetics of post-ASCT lymphocyte recovery>or=500 cells/microl (K-ALC) on overall survival (OS) and progression-free survival (PFS). K-ALC was a predictor of OS and PFS when the Cox proportional hazards model was used with K-ALC entered as a continuous variable (p<0.0001). Multivariate analysis demonstrated K-ALC recovery post-ASCT to be an independent prognostic indicator for OS and PFS. These data support our hypothesis that the K-ALC post-ASCT is associated with clinical outcome in NHL.  相似文献   
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We examined the effect of dietary supplementation with L-arginine on breath condensate VEGF, exhaled nitric oxide (NO), plasma erythropoietin, symptoms of acute mountain sickness, and respiratory related sensations at 4,342 m through the course of 24 h in seven healthy male subjects. Serum L-arginine levels increased in treated subjects at time 0, 8, and 24 h compared with placebo, indicating the effectiveness of our treatment. L-arginine had no significant effect on overall Lake Louise scores compared with placebo. However, there was a significant increase in headache within the L-arginine treatment group at 12 h compared with time 0, a change not seen in the placebo condition between these two time points. There was a trend (p = 0.087) toward greater exhaled NO and significant increases in breath condensate VEGF with L-arginine treatment, but no L-arginine effect on serum EPO. These results suggest that L-arginine supplementation increases HIF-1 stabilization in the lung, possibly through a NO-dependent pathway. In total, our observations indicate that L-arginine supplementation is not beneficial in the prophylactic treatment of AMS.  相似文献   
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Pediatric and young adult renal transplant recipients may experience feelings of depression and emotional trauma. A study was conducted to (1) determine the prevalence of depression and emotional trauma and (2) assess the utility of the Formal Elements of Art Therapy Scale (FEATS). Sixty-four renal transplant recipients, 6-21 yr of age, were evaluated using self-report measures (CDI and Davidson) and art-based assessments. Subject art was analyzed by art therapists using seven of the 14 elements of the (FEATS), to assess depression. Unlike CDI and Davidson self-report testing, all patients were able to complete the art-based directives. When self-report measures and art-based assessments were combined, 36% of the study population had testing results consistent with depression and/or post-traumatic stress. The FEATS assessments identified a subset of patients who were not identified using the self-report measures. There was a correlation between CDI and Davidson scores (p < 0.0001), Davidson scores correlated with hospital days (p = 0.05), and FEATS correlated with height Z score (p = 0.04) and donor type (p = 0.01). Patients who required psychological interventions including antidepressant therapy, psychological counseling and psychiatric hospitalization during the year after the study were identified as depressed. Sensitivity for FEATS and CDI were 22 and 50% respectively. The results suggest that while art therapy may be of utility in the identification of pediatric and young adult transplant recipients who are suffering from depression, FEATS analysis appears to lack sufficient sensitivity to warrant its use in this population. Study of other quantitative art-based assessment techniques may be warranted.  相似文献   
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Objectives: Severity and timing are key aspects of disability experience for individuals. They also generate a populations disability structure (prevalence, counts, patterns). We study links among severity, duration, and structure for community-dwelling adults in the US.Methods: The data source is the National Health Interview Survey Disability Supplement. Disabilities in personal care (ADL), household management (IADL), and physical functions (PLIM) are analyzed.  相似文献   
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