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71.
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Predicting abdominal adipose tissue in overweight Latino youth.   总被引:1,自引:0,他引:1  
OBJECTIVES: 1) Examine associations between visceral adipose tissue (VAT), subcutaneous abdominal adipose tissue (SAAT), and anthropometric and demographic variables; 2) generate and cross-validate prediction equations for estimating VAT and SAAT in overweight Latino children. STUDY DESIGN: Cross-sectional. PARTICIPANTS: 196 overweight 8-13-year-old Latino youth. Two-thirds (n = 131) were randomly assigned to a development group to generate prediction equations for VAT and SAAT; one-third (n = 65) was used as a cross-validation group. METHODS AND PROCEDURES: Anthropometric measurements (height, weight, skinfold thicknesses, and circumferences) were performed. VAT and SAAT were measured using magnetic resonance imaging (MRI). RESULTS: The strongest univariate correlate for VAT was waist circumference (WC) (r = 0.65, p < 0.01) while the strongest correlate for SAAT was hip circumference (r = 0.88, p < 0.001). Regression analyses showed approximately 50% of the variance in VAT was explained by WC (43.8%), Tanner stage (4.2%) and calf skinfold (1.7%). Variance in the SAAT model was explained by WC (77.8%), triceps skinfold (4.2%) and gender (2.3%). Residual analyses showed no bias in either equation. Though mean differences between measured and predicted VAT and SAAT were small, there was a large degree of variability at the individual level especially for VAT. CONCLUSIONS: Both VAT and SAAT prediction equations performed well at the group level, but the relatively high degree of variability suggests limited clinical utility of the VAT equation. MRI is currently required to derive an accurate measure of VAT at the individual level.  相似文献   
73.

Background  

Our goal was to quantify the evidence that is available to the physicians of a pediatric emergency department (PED) in making treatment decisions. Further, we wished to ascertain what percentage of evidence for treatment provided in the PED comes from pediatric studies.  相似文献   
74.
Imexon is an aziridine-containing small molecule currently in Phase I clinical trials. This agent has been shown to bind to thiols and increase intracellular oxidants, inducing apoptosis in hematologic cancer cells. Pancreatic cancers are known to be sensitive to oxidation, suggesting this disease may be an appropriate target for this agent. The current report examines the activity of imexon in pancreatic cells. Imexon induced concentration-dependent and time-dependent apoptosis in a panel of six human pancreatic carcinoma cell (PCC) lines. The mean IC50 (SD) for growth inhibition by the SRB assay was 200 (101) µM for a 48 h exposure with a range of 64–358 µM. Cell killing was schedule-dependent, favoring exposure times ≥48 h. Imexon-treated MiaPaCa-2 cells underwent non-lethal growth arrest following exposure to concentrations ≤200 µM for 48 h. When concentrations were increased to 300 µM for ≥48 h, the MiaPaCa-2 cells arrested in G2 phase and activated caspases 3, 8, and 9 were detected. After a 72 h exposure to the IC80 concentration of imexon, cells exhibited a loss of mitochondrial membrane potential detected by CMXRos staining. However, there was no loss of reduced cellular thiols unless very high concentrations of ≥400 µM were used. In contrast, reactive oxygen species (ROS) were elevated in a dose-dependent fashion, starting at very low imexon concentrations. Imexon also significantly inhibited MiaPaCa-2 tumor growth in SCID mice at 100 mg/kg/d for 9 d. The tumor growth inhibition (% T/C) was 27% of control, and the tumor growth delay was 21 d, indicating an active agent by NCI standards. The levels of imexon that are cytotoxic in human PCC’s are achievable based on the preliminary results of the ongoing Phase I trial. Imexon appears to be active against PCCs in vitro and has an entirely novel mechanism of action involving G2 arrest, accumulation of ROS, and the induction of apoptosis.  相似文献   
75.
Breast Cancer Research and Treatment - Many patients seek breast reconstruction following mastectomy. Debate exists regarding the best reconstructive option. The authors evaluate outcomes comparing...  相似文献   
76.
OBJECTIVE: To determine the validity of patients' self-reported symptoms of vulvovaginal candidiasis and the accuracy of clinical wet mount examinations compared with vulvovaginal yeast culture results in a specialty clinic. STUDY DESIGN: A retrospective chart review of new patients seen at the Saint Louis University Vulvar and Vaginal Disease Clinic from January 2005 to March 2006 was performed. Patients' age, medication use, symptom scores on a rating scale for vaginal/vulvar pain, burning, itching, dyspareunia and wet mount analyses were compared with yeast culture results. RESULTS: Of 153 patients, 40 had positive yeast cultures (prevalence rate 26.1%). Compared with yeast cultures, self-reported symptom scores >4 resulted in high sensitivity (90%) and low specificity (7%). Positive wet mount result showed low sensitivity (18%) and high specificity (99%). Patient symptom scores were a poor predictor of yeast infections based on yeast culture results. No correlation was found among wet mount, self-reported symptoms and yeast culture results. No significant difference between age or symptom scores to culture result was found. CONCLUSION: Wet mount analysis for recurrent or persistent patient symptoms should be reevaluated. Self-reported symptoms are not reliable for diagnosis. Wet mount analysis resulted in low sensitivity. Yeast cultures should be considered the gold standard for identification of vulvovaginal candidiasis in persistent or recurrent cases.  相似文献   
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78.
This study uses two types of independent variables, age and the location of the physical wound, to develop a model of injury patterning that identifies violent behavior without direct observation of the assault. In this research, domestic violence injuries are compared to accidental injuries. The results indicate that there are specific and predictable injury patterns that separate abuse from other kinds of wounds. A logistic regression model was developed to identify the regions of the body most susceptible to injury from domestic assault. Using the age of the victim and the injury regions, probabilities were calculated to determine which wounds were caused by abuse.  相似文献   
79.
In nearly 50 per cent. of the cases, virulent trypanosome virus inoculated directly through the stomach wall of rats failed to infect these animals. The percentage of infections after inoculation of this kind seemed to vary with the virus. Surra of India proved to be the most virulent, and caderas the least. Nagana and dourine occupied intermediate positions. The rats that escaped infection showed no trace of immunity when tested with small quantities of the same virus between the twelfth and the twenty-eighth days after the intra-stomachal inoculations. The majority of the rats tested for immunity with surra of India and nagana seemed to have acquired, instead of an immunity, a certain hypersensitiveness to infection. Five of the seven nagana rats died before their controls. The results of testing the vitality of the trypanosomes of caderas, dourine, and nagana introduced directly into the stomachs and intestines of living rats seem to show that both motility and virulence are usually lost in less than two hours. Surra of India proved exceptionally resistant to the harmful influences of the stomach, for in one case, surra trypanosomes introduced into the intestines were found to be sluggishly motile in the stomach one hour and fifty-five minutes later, and in another instance, surra parasites injected into the stomach were found, when removed from that organ two hours later, to be actively motile and infectious.  相似文献   
80.
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