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71.
Benzoxazole-2-thiol ( 1 )/dibenzoyl peroxide (Bz2O2) was used as photoinitiator for the polymerization of methyl methacrylate (MMA) in bulk and in solution. The study of initiator decomposition was conducted spectrophotometrically. Kinetic studies of the photopolymerization indicated the formation of a complex between 1 and Bz2O2 in the stoichiometric ratio 2:1. The initiation is believed to occur via in situ formation of bis(benzoxazol-2-yl) disulfide in the presence of light.  相似文献   
72.
Volatile components from diesel exhaust particles and coal gasifier process gas condensate were vacuum fractionated by cryogenic distillation and identified by infrared spectroscopy and gas chromatography/mass spectrometry. The vacuum distillation line consisted of a sample flask and nine traps cooled from 0°C to ?196°C in approximately 20°C steps. The pressure in the vacuum line of about 10?2 Torr was maintained with a vacuum pump. Separated compounds were identified by comparison to reference infrared spectra and confirmed by comparison with standards when practical. Volatile compounds identified from the diesel exhaust particle sample included NOx, carbon dioxide, sulfur dioxide, alkanes, aldehydes, and one and two ring aromatic hydrocarbons. Volatile compounds identified in process gas condensate from a coal gasifier were ammonia, carbonyl sulfide, carbon dioxide, C3-C7 hydrocarbons, one and two ring aromatic hydrocarbons, and phenols. Volatile components collected at either 0° or ?24°C were evaluated to determine their genotoxicity using the Chinese hamster ovary/hypoxanthine-guanine phosphoribosyltransferase (CHO/HGPRT) assay. Neither the gasifier condensate nor diesel particle samples produced mutations at the HGPRT locus. The diesel samples were not cytotoxic at the concentrations tested (100 μg/ml) but the gasifier samples resulted in 50% cell killing at concentrations between 25 and 100 μg/ml depending on the temperature of collection and the test conditions. Vacuum desorption with cryogenic distillation has provided a means to separate the volatile components in complex environmental samples to allow chemical and biological characterization of these components.  相似文献   
73.
ObjectiveFinancial toxicity (FT) has been defined as the patient-level impact of the costs of cancer care. Our objective was to better characterize FT among bladder cancer patients as well as oncologic, demographic and insurance characteristics related to FT.MethodsWe conducted a cross-sectional survey of the Bladder Cancer Advocacy Network Patient Survey Network using the validated COST (COmprehensive Score for financial Toxicity) questionnaire. Our primary outcome was relative degree of FT, with lower COST scores corresponding to worse FT. Wilcoxon rank sum tests and multiple regression were used to evaluate differences in demographic, diagnostic and treatment characteristics as they related to degree of FT.ResultsAmong 226 patients, median age was 68 years with 64% male, 83% married, and 49% with Medicare with supplemental insurance. Respondents reported an average of 65 months since diagnosis, with 62% reporting noninvasive disease. Mean COST was 28.4 (range 0–44). On multivariable analysis, patients who were younger, with a household annual income less than $50,000, not retired, or with insurance that was neither Medicare nor employer paid were significantly more likely to have worse FT. A majority of respondents (63.5%) agreed or strongly agreed that they would be interested in discussing cost in the context of their treatment preferences, independent of COST score (P = 0.24).ConclusionsA national cross-sectional survey demonstrated high prevalence of FT which was worse among younger patients with lower incomes, not retired, and without employer-paid or Medicare insurance. Most patients preferred to discuss treatment costs with their bladder cancer provider.  相似文献   
74.
Archives of Sexual Behavior - The fraternal birth order effect (FBOE) is the repeated finding that older brothers increase the odds of homosexuality in later-born males. It has been our working...  相似文献   
75.
Bulletin of Environmental Contamination and Toxicology - An experiment was conducted to study the effects of co-composted products of municipal solid waste (MSW) and pigeon pea biochar (PPB) on...  相似文献   
76.
77.
OBJECTIVES: The aim of this work was to examine changes in the smoking behavior of elderly Mexican Americans in the southwestern United States from the early 1980s to the early 1990s. METHODS: Data from the 1993-1994 Hispanic EPESE study (n = 2,809) on persons ages 65 to 74 and 75 to 84 residing in the five southwestern states were compared with data from the 1982-1984 Hispanic HANES study (n = 753, persons ages 55 to 74), which included a Mexican American sample from the same five southwestern states. RESULTS: Rates of current smoking in 1993-1994 for persons ages 65 to 74 were approximately half the rates for persons of the same age a decade earlier. Smoking rates for persons ages 75 to 84 in 1993-1994 were significantly lower than rates for persons ages 65 to 74 a decade earlier. Finally, rates for persons ages 65 to 74 in 1993-1994 were significantly lower than those for persons ages 55 to 64 in 1982-1984. CONCLUSIONS: Although some of the declines in smoking in recent years represent aging effects (including declines due to greater mortality among smokers), the much lower rates for same-age people (65 to 74) over the 10-year period are more significant in that they represent cohort differences. It appears that the broader public health message that is causing the general population to quit smoking is reaching the elderly Mexican American population of the Southwest.  相似文献   
78.
Pavement dwelling is likely to aggravate malnutrition among its residents due to extreme poverty, lack of dwelling and access to food and their exposure to polluted environment. Paucity of information about nutritional status of street children compared to that among urban slum dwellers, squatters or rural/tribal population is quite evident. The present study revealed the magnitude of Protein Energy Malnutrition (PEM) and few associated factors among a sample of 435 underfives belonging to pavement dweller families and selected randomly from clusters of such families, from each of the five geographical sectors of Calcutta city. Overall prevalence of PEM was found almost similar (about 70%) to that among other 'urban poor' children viz. slum dwellers etc., but about 16% of them were found severely undernourished (Grade III & V of IAP classification of PEM). About 35% and 70% of street dweller children had wasting and stunting respectively. Severe PEM (Grade III & IV) was more prevalent among 12-23 months old, girl child, those belonged to illiterate parents and housewife mothers rather than wage earners. It also did increase with increase of birth rate of decrease of birth interval.  相似文献   
79.
BACKGROUND: Maternal serum chorionic gonadotropin is measured to screen for fetal chromosomal abnormalities. Whether the results can also be used to predict the risk of complications or an adverse outcome of pregnancy is not known. METHODS: We reviewed the medical records of 28,743 girls and women in whom chorionic gonadotropin was measured during the second trimester of pregnancy (between July 1, 1995, and January 31, 1997), seeking information about the complications and outcome of their pregnancies. We excluded girls and women who had preexisting risk factors for complications or an adverse outcome of pregnancy. RESULTS: Higher serum chorionic gonadotropin concentrations were associated with higher rates of stillbirth (odds ratio for every increase in chorionic gonadotropin of 1 multiple of the median, 1.4; 95 percent confidence interval, 1.1 to 1.9). There was no relation between higher serum chorionic gonadotropin concentrations and the risk of gestational diabetes, premature rupture of membranes or intrauterine growth retardation or small size for gestational age (odds ratio, 1.1; 95 percent confidence interval, 0.9 to 1.2). Higher serum chorionic gonadotropin concentrations were associated with a risk of placental abnormalities (odds ratio, 1.5; 95 percent confidence interval, 1.3 to 1.7), pregnancy-induced hypertension (odds ratio, 1.4; 95 percent confidence interval, 1.3 to 1.5), and preterm delivery without pregnancy-induced hypertension (odds ratio, 1.1; 95 percent confidence interval, 1.0 to 1.2). Inclusion in certain racial or ethnic categories (black, Filipino or Pacific Islander, unknown race or ethnic group, and "other," which included those of Middle Eastern descent and Native Americans) was a better predictor of the risk of an adverse outcome than serum chorionic gonadotropin values. CONCLUSIONS: Measurements of serum chorionic gonadotropin are of little clinical value for predicting the risk of complications and the outcome of pregnancy.  相似文献   
80.
The magnitude of serum thyroxine (T4) binding capacity (sBC) dependent bias in the AXSYM free thyroxine (FT4) assay was assessed using two recently described tests. One of the tests uses a direct equilibrium dialysis (ED) FT4 assay as the reference method. The results obtained with the AXSYM method were compared with those obtained by the ED FT4 method in patient sera having a wide range of sBC. The other test involves comparison of the FT4 results obtained following dilution of sera by an inert buffer, to theoretically derived FT4 results. As serum dilution causes a predictable decrease in sBC, the demonstration of a negative bias whose magnitude increases in parallel to the dilution, is indicative of an sBC-dependent bias. The AXSYM FT4 assay exhibited a significant sBC-dependent bias. This sBC-dependent bias is likely to have been caused by the presence of significant amounts of T4 binding proteins in the assay reagents.  相似文献   
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