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991.
Arenosclerins A (2), B (3), and C (4), as well as haliclonacyclamine E (1), are new tetracyclic alkylpiperidine alkaloids isolated from a new species of marine sponge belonging to the order Haplosclerida, Arenosclera brasiliensis, a species endemic to the southeastern Brazilian coast. The alkaloids were isolated as their hydrochloride salts and identified by analysis of spectroscopic data. Data obtained from (1)H-(1)H COSY, HMBC, and HSQC-TOCSY NMR experiments allowed complete assignment of the (1)H and (13)C resonances, and analysis of the NOESY and ROESY spectra showed that the only differences between 2, 3, and 4 were the relative stereochemistries of the bispiperidine ring system. Arenosclerins A-C are the first haliclonacyclamine/halicyclamine-related alkaloids with a hydroxy group in the bridging alkyl chain.  相似文献   
992.
This cross-sectional study aimed to identify the prevalence of smoking among employees of a university hospital in Southern Brazil. Data collection happened in 2008, during the periodic health exam, using a questionnaire, according to the smoking status of the employees. The sample consisted of 1,475 subjects, in which 979 (66.4%) were non-smokers, 295 (20%) former smokers and 201 (13.6%) smokers. Smoking was more prevalent among employees with lower education levels and among professionals in administrative positions. Among smokers, low dependence was identified, as well as desire and high degree of motivation to stop smoking, with health concerns as the main reason. Thus, taking into account the motivation of smokers to stop smoking, this is an appropriate time for health education and specific support to employees in the process of smoking cessation.  相似文献   
993.
A series of 2-(benzo[d]thiazol-2-yl)-8-substituted-2H-pyrazolo[4,3-c]quinolin-3(5H)-ones (3a-g) have been synthesized and evaluated for their in vitro antiproliferative activities against four human cancer cell lines: MDA-MB-435 (breast), HL-60 (leukemia), HCT-8 (colon) and SF-295 (central nervous system). The results showed that the compounds 3b (2-(benzo[d]thiazol-2-yl)-8-methyl-2H-pyrazolo[4,3-c]quinolin-3(5H)-one) and 3c (2-(benzo[d]thiazol-2-yl)-8-bromo-2H-pyrazolo[4,3-c]quinolin-3(5H)-one) exhibited good cytotoxicity for three cell lines with IC50 values lower than 5 μg/mL. Analysis of theoretical toxicity risks have shown medium tumorigenic and irritant risks related to 3b and 3c in contrast to doxorubicin, the positive control.  相似文献   
994.
The available chemotherapy for Chagas disease, caused by Trypanosoma cruzi, is unsatisfactory; therefore, there is an intense effort to find new drugs for the treatment of this disease. In our laboratory, we have analyzed the effect on bloodstream trypomastigotes of 16 new naphthoquinone analogues of β-lapachone modified in the pyran ring, aiming to find a new prototype with high trypanocidal activity. The new compounds presented a broad spectrum of activity, and five of them presented IC50/24 h in the range of 22-63 μM, whereas β-lapachone had a higher value of 391.5 ± 16.5 μM.  相似文献   
995.
The right aberrant subclavian artery or "arteria lusoria" is the most common anatomical variant of the embryonic development of the aorta and its branches, with a presence in 0.5-2% of the population. Less frequently, a right aortic arch with aberrant left subclavian artery may be present. These anatomical variations should be included in the differential diagnosis of superior mediastinal widening seen on chest radiographs. In this report, we present a right aortic arch with left aberrant subclavian artery dilated at its origin (Kommerell's diverticulum) as a cause of superior mediastinal widening detected incidentally on a chest radiograph.  相似文献   
996.
The main nutritional deficiencies during childhood, namely anemia and malnutrition, are predominantly related to socio-economic factors. Thus, as the Bolsa Família Program (BFP) is the main policy to combat poverty, it is expected that it will have an impact on child nutrition. The aim was to analyze the differences in the nutritional situation of children registered with the BFP of a municipality located in Zona da Mata of Minas Gerais state. 446 children aged between 6 and 84 months were evaluated, of which 262 were non-beneficiaries and 184 were beneficiaries. Nutritional evaluation included analysis of weight and height parameters through weight/age, weight/height, height/age and Body Mass Index/age indexes and hemoglobin levels, using the Hemocue. The prevalence of anemia, short stature and obesity were 22.6, 6.3 and 5.2%, respectively, and there were no statistical differences between beneficiaries and non-beneficiaries. The beneficiary group initially had worse socio-economic conditions, but with the BFP it managed to financially match the non-beneficiary group. It is possible that the similarity between the two groups, also in the nutritional status, can be attributed to the program benefits, due to the financial funding as well as to the nutritional monitoring required as a condition of the program.  相似文献   
997.
998.
This cross-sectional study aimed to identify the social and biological determinants of anemia in children enrolled in the Brazilian Income Transfer Program (PBF). The study evaluated 446 children (69.1% of the total enrolled) ranging from 6 to 84 months of age, of whom 262 were receiving the income transfer (60.2% of the beneficiaries) and 184 were not (87.6% of the non-beneficiaries). Testing for anemia was performed with the Hemocue portable hemoglobinometer, and the cutoff points were set at 11.0 and 11.5 g/dL, according to age bracket. The data were analyzed using Poisson hierarchical regression with robust variance for multivariate analysis. There was no difference in the anemia prevalence rates between the beneficiary and non-beneficiary groups. Risk factors for anemia were low paternal schooling, cesarean birth, consumption of untreated water, stunting, and age less than 24 months. Prevalence of anemia in the group of non-beneficiary children under two years of age was significantly higher than in the beneficiary group in the same age bracket, suggesting the importance of the PBF income transfer for preventing anemia in children.  相似文献   
999.
This cross-sectional study focused on alcohol consumption according to gender, age, income, and schooling in Jequié, Bahia State, Brazil. The random sample consisted of 270 individuals over 14 years of age living in the urban area of Jequié from January to March 2010. Alcohol consumption was assessed using the Alcohol Use Disorders Identification Test (AUDIT). Of the total sample, 21.8% consumed four or more drinks on a typical day, 14.1% admitted having caused any harm after drinking, and 26.3% reported that someone had already suggested they should stop drinking. Forty percent of men had more than four drinks on a typical day, and 50.5% of young people drank frequently. Distribution of the variables was consistent with higher frequency and greater amounts of alcohol among men and young people. There was a large proportion of heavy episodic alcohol consumption. The study identified vulnerable groups that are still not addicted to alcohol, and that should be targeted for public health promotion and prevention policies.  相似文献   
1000.
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