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Radioiodinated serum albumin has been used as a blood marker to define and quantitate physiological volumes for 12 organs and tissue types. The concentration of gallium-67 in "blood-free" tissues of rats was also determined at various times after intravenous administration. Tissues were divided into two kinetically distinguishable types based on reported nonuniform distribution of the blood marker and the gallium distribution observed in the present study. Gallium distribution into the liver and spleen was observed to be slow, with a discernable accumulation phase followed by monoexponential elimination. In contrast, gallium accumulation into the stomach, small and large intestines, heart, lung, skin/adipose tissue, and muscle was rapid and elimination was monophasic.  相似文献   
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European Journal of Epidemiology - The apolipoprotein E allele 4 (APOE-ε4) is established as a major genetic risk factor for cognitive decline and late-onset Alzheimer’s disease....  相似文献   
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This study compares the characteristics of rural hospitals with urban safety-net hospitals and with "other urban hospitals" (non-teaching, non-safety-net urban hospitals that provide mainstream care in the United States). The objective is to examine if there are similarities between rural and urban safety-net hospitals, both of which serve underserved populations. The authors also wish to study if there are areas in which rural and urban safety-net hospitals are closer together compared to "other" urban hospitals. Based on the results, some potential areas of cooperation between rural and urban safety-net hospitals are discussed.  相似文献   
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PURPOSE: RRM1 has important functions in the determination of the malignant phenotype. It controls cell proliferation through deoxynucleotide production and metastatic propensity through PTEN induction. It is located in a region of loss of heterozygosity in non-small-cell lung cancer (NSCLC), which is a predictor of poor survival. We hypothesized that RRM1 expression would be a significant predictor of outcome in NSCLC. PATIENTS AND METHODS: A retrospective data set of 49 patients and a prospective data set of 77 patients with resectable NSCLC were studied. RNA was extracted from tumor and normal lung tissue, and expression of the genes RRM1, PTEN, and RRM2 was determined by real-time quantitative polymerase chain reaction. RESULTS: RRM1 expression was significantly correlated with PTEN and RRM2 expression in tumor tissue. RRM1 and PTEN expression in tumor tissue was highly predictive of overall (P =.011 and.018, respectively) and disease-free survival (P =.002 and.026, respectively). Patients with high levels of expression lived longer and had disease recurrence later than patients with low levels of RRM1 and PTEN. In a multivariate analysis, high RRM1 expression was predictive of long survival independent of tumor stage, performance status, and weight loss. CONCLUSION: RRM1 is a biologically and clinically important determinant of malignant behavior in NSCLC. Knowing the level of expression of this gene adds significant information to management decisions independent of the currently used outcome predictors of tumor stage, performance status, and weight loss. Future clinical trials should stratify patients based on expression of this gene to avoid unwanted biases.  相似文献   
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Objective To assess the risk of maternal osteoporosis associated with antenatal corticosterioid administration for neonatal respiratory distress syndrome prophylaxis.
Design Prospective longitudinal study.
Setting Maternity unit of Chelsea and Westminster Hospital, London.
Population Fourteen pregnant women who received dexamethasone therapy for fetal lung maturation in anticipation of delivery before 34 completed weeks of gestation.
Methods Blood samples were collected before dexamethasone administration, 24 hours and 48 hours after the course of dexamethasone, and within 24 hours of delivery. Serum levels of carboxy terminal pro-peptide of type I pro-collagen (PICP) were measured to monitor the rate of bone formation, and serum levels of cross-linked carboxy terminal telopeptide (ICTP) were measured as a marker of bone resorption.
Main outcome measures Changes in the markers of bone turnover following dexamethasone administration.
Results Serum PICP levels dropped 24 hours after dexamethasone therapy (   P = 0.001  ), but partially recovered by 48 hours (   P = 0.014  ) to reach higher than pre-therapy levels at delivery (   P = 0.044  ). Although there were no corresponding changes in the serum levels of ICTP after 24 and 48 hours of therapy, levels increased from pretherapy to delivery (   P = 0.006  ).
Conclusion Antenatal corticosteroid therapy leads to a transient suppression of, followed by an increase in, bone formation without any significant alteration in the pattern of bone resorption expected during pregnancy.  相似文献   
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Two rare cases of Waardenburg type II are reported. First case had three main features of WS-profound SN hearing loss, hetrochromia iris and white forelock of hair. Second case had moderate SNHL and depigmentation of hair. Key words: Hetrochromia iris, white forelock hair.  相似文献   
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