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81.
Cell metabolism self-organizes into two types of dissipative structures: chemical oscillations and traveling metabolic waves. In the present study we test the hypothesis that traveling NAD(P)H waves within neutrophils are associated spatially and temporally with the release of reactive oxygen metabolites (ROMs). Using high-speed optical microscopy and taking advantage of the autofluorescence of NAD(P)H, we have observed the propagation of NAD(P)H waves within cells. When NAD(P)H waves reach the lamellipodium of morphologically polarized neutrophils, a diffusing plume of superoxide is released as evidenced by the conversion of hydroethidine in the extracellular environment to ethidium bromide. Parallel results were obtained by using high-speed emission microspectrophotometry. These experiments indicate that the spatial and temporal properties of NAD(P)H waves are transformed into ROM pulses in the extracellular environment. Propagating NAD(P)H waves allow neutrophils to specifically deliver substrate to the lamellipodium at high concentrations, thus facilitating the local and periodic release of ROMs in the direction of cell movement and/or a target.  相似文献   
82.
BACKGROUND: The purpose of this study was to develop a rapid and accurate diagnostic test for palpable breast masses in women under age 40. METHODS: Masses were evaluated utilitzing a modified triple test score (MTTS), which assigned scores of 1 point for benign, 2 points for suspicious, or 3 points for malignant findings from physical examination, ultrasonography, and fine needle aspiration. The MTTS was the sum of the three scores and was correlated with biopsy or follow-up. RESULTS: Among 113 masses, 100 scored 3 points, 8 scored 4 points; all were benign. Three scored 5 points; 1 was malignant. Two scored >or=6 points: both were malignant. CONCLUSIONS: The MTTS has 100% diagnostic accuracy when other than 5 points. Masses scoring or=6 points may proceed to definitive therapy. Masses scoring 5 points (3%) require biopsy. This approach avoids open biopsy in the majority of cases, while capturing all malignancies.  相似文献   
83.
Monascus purpureus is a fungus that has been tradi-tionally used in China for thousands of years to produce ricewine . Traditionally the fungus is used to ferment non-gluti-nous cooking of rice ,to produce a kind of famous red ricewine .Its main traditional indications consist of disordersdue to the accumulation of fats (nosologically linked withthe problems of stasis of circulation in traditional Chinesemedicine) ,liver disorders and some forms of tumor as ithelps i mprove the circulation of …  相似文献   
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Data on body composition in conjunction with reference centiles are helpful in identifying the severity of growth and nutritional disorders in infancy and for evaluating the adequacy of treatment given during this important period of rapid growth. Total body fat (TBF) and fat-free mass (FFM) were estimated from total body electrical conductivity (TBEC) measurements in 423 healthy term Caucasian infants, aged 14-379 days. Cross sectional age, weight, and length related centile standards are presented for TBF and FFM. Centiles were calculated using Altman's method, based on polynomial regression and modelling of the residual variation. The TBF percentage steeply increased during the first half year of life, and slowly declined beyond this age. Various simple TBEC derived anthropometric prediction equations for TBF and FFM are available to be used in conjunction with these standards. Regression equations for the P50 and the residual SD, depending on age, weight, or length, are provided for constructing centile charts and calculating standard deviation scores.  相似文献   
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Prognosis in childhood dermatomyositis   总被引:1,自引:0,他引:1  
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89.
This study of etoposide in thyroid cancer was designed to determine the activity and toxicity of etoposide in a variety of inoperable, thyroid hormone insensitive, and radio-iodine resistant primary cancers of the thyroid. The patients were required to have an ECOG performance status of at least 3 and no previous exposure to chemotherapy. The etoposide was given at a dose of 140 mg/m2 daily for 3 days and every 3 weeks until progression. The study was closed after 18 months because of poor accrual. There were no responses seen among the 10 patients accrued. The toxicity was primarily hematologic. There was no evidence of activity of etoposide in thyroid carcinoma, although this study lacked significant power because of the poor accrual.  相似文献   
90.

Objective

To identify opportunities to improve care value for children with disabilities (CWD), we examined CWD prevalence within a commercially insured population and compared outpatient care quality and annual health plan spending levels for CWD relative to children with complex medical conditions without disabilities; children with chronic conditions that are not complex; and children without disabling, complex, or chronic conditions.

Methods

This cross-sectional study comprised 1,118,081 person-years of Blue Cross Blue Shield Massachusetts data for beneficiaries aged 1 to 19years old during 2008 to 2012. We combined the newly developed and validated Children with Disabilities Algorithm with the Pediatric Medical Complexity Algorithm to identify CWD and non-CWD subgroups. We used 14 validated or National Quality Forum–endorsed measures to assess outpatient care quality and paid claims to examine annual plan spending levels and components.

Results

CWD constituted 4.5% of all enrollees. Care quality for CWD was between 11% and 59% for 8 of 14 quality measures and >80% for the 6 remaining measures and was generally comparable to that for non-CWD subgroups. Annual plan spending among CWD was a median and mean 23% and 53% higher than that for children with complex medical conditions without disabilities, respectively; CWD mean and median values were higher than for all other groups as well.

Conclusions

CWD were prevalent in our commercially insured population. CWD experienced suboptimal levels of care, but those levels were comparable to non-CWD groups. Improving the care value for CWD involves a deeper understanding of what higher spending delivers and additional aspects of care quality.  相似文献   
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