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排序方式: 共有9002条查询结果,搜索用时 15 毫秒
991.
Rodrigo N. Angerami Milena Câmara Márcia R. Pacola Regina C.M. Rezende Raquel M.R. Duarte Elvira M.M. Nascimento Silvia Colombo Fabiana C.P. Santos Ruth M. Leite Gizelda Katz Luiz J. Silva 《Ticks and Tick》2012,3(5-6):346-348
Brazilian spotted fever (BSF) caused by Rickettsia rickettsii is the most important rickettsiosis and the only reportable tick-borne disease in Brazil. In Brazil, the hard tick Amblyomma cajennense is the most important BSF vector; however, in São Paulo State, A. aureolatum was also recognized as a vector species in remaining Atlantic forest areas near the metropolitan area of São Paulo city. We analyzed clinical and epidemiological features of BSF cases from two distinct areas where A. cajennense (Area 1) and A. aureolatum (Area 2) are the incriminated vectors. The clinical features demonstrate the same severity pattern of BSF in both endemic areas. Differences in seasonality, patient characteristics (median age and gender), and epidemiological risk factors (animals host contact and vegetation characteristics) were observed and possibly could be attributed to the characteristics of each vector and their typical biological cycle (hosts and environment). 相似文献
992.
993.
Conlon MA Kerr CA McSweeney CS Dunne RA Shaw JM Kang S Bird AR Morell MK Lockett TJ Molloy PL Regina A Toden S Clarke JM Topping DL 《The Journal of nutrition》2012,142(5):832-840
Resistant starch (RS), fed as high amylose maize starch (HAMS) or butyrylated HAMS (HAMSB), opposes dietary protein-induced colonocyte DNA damage in rats. In this study, rats were fed Western-type diets moderate in fat (19%) and protein (20%) containing digestible starches [low amylose maize starch (LAMS) or low amylose whole wheat (LAW)] or RS [HAMS, HAMSB, or a whole high amylose wheat (HAW) generated by RNA interference] for 11 wk (n = 10/group). A control diet included 7% fat, 13% protein, and LAMS. Colonocyte DNA single-strand breaks (SSB) were significantly higher (by 70%) in rats fed the Western diet containing LAMS relative to controls. Dietary HAW, HAMS, and HAMSB opposed this effect while raising digesta levels of SCFA and lowering ammonia and phenol levels. SSB correlated inversely with total large bowel SCFA, including colonic butyrate concentration (R(2) = 0.40; P = 0.009), and positively with colonic ammonia concentration (R(2) = 0.40; P = 0.014). Analysis of gut microbiota populations using a phylogenetic microarray revealed profiles that fell into 3 distinct groups: control and LAMS; HAMS and HAMSB; and LAW and HAW. The expression of colonic genes associated with the maintenance of genomic integrity (notably Mdm2, Top1, Msh3, Ung, Rere, Cebpa, Gmnn, and Parg) was altered and varied with RS source. HAW is as effective as HAMS and HAMSB in opposing diet-induced colonic DNA damage in rats, but their effects on the large bowel microbiota and colonocyte gene expression differ, possibly due to the presence of other fiber components in HAW. 相似文献
994.
995.
Joy Noel Baumgartner Chelsea Morroni Regina Dlakulu Mlobeli Conrad Otterness Geoffrey Buga Mario Chen 《Studies in family planning》2012,43(4):305-314
Arriving late for scheduled contraceptive reinjections is common in many countries and contributes to discontinuation when providers are unsure how to manage such clients. A clinic‐randomized cohort and cross‐sectional study with more than 5,000 clients using injectable contraceptives was conducted in the Eastern Cape province of South Africa to test the effectiveness of a provider job aid for managing late‐returning clients and promoting continued use of the method. A marginally significant difference in reinjection rates between intervention and control groups was found for those up to two weeks late, and reanalysis excluding one clinic that experienced stockout issues revealed a significant difference. The difference in reinjection rates for those 2–12 weeks late was also found to be significant. The one‐reinjection cycle continuation rate for the intervention group was higher than that for the control group, but the difference was not statistically significant. Appropriate management of late‐returning clients is critical, and this study illustrates that reinjection rates can be significantly increased with a low‐resource provider job aid. 相似文献
996.
Wierzejska R 《Roczniki Państwowego Zak?adu Higieny》2012,63(2):141-147
Caffeine is widely consumed by people of all ages. In the last period a market of caffeine-containing products, particularly energy drinks and food supplements increased. Caffeine for years is under discussion, whether has positive whether adverse impact on health. Children are a group of special anxieties. Caffeine is a stimulant of central nervous system and therefore is probably the most commonly used psychoactive substance in the world. The physiological effect of caffeine and the lack of nutrition value causes a great interest its impact on health, especially with reference to the risk of cardiovascular diseases. Results of scientific research are not clear. The influence of caffeine on the human body is conditioned with the individual metabolism of caffeine which also depends on many endogenic and environmental factors. According to the current knowledge moderate caffeine intake by healthy adults at a dose level of 400 mg a day is not associated with adverse effects, but it also depends on other health determinants of a lifestyle. Excessive caffeine consumption can cause negative health consequences such as psychomotor agitation, insomnia, headache, gastrointestinal complaints. Adverse effect of caffeine intoxication is classified in World Health Organization's International Classification of Diseases (ICD-10). Metabolism of caffeine by pregnant woman is slowed down. Caffeine and its metabolites pass freely across the placenta into a fetus. For this reason pregnant women should limit caffeine intake. Children and adolescents should also limit daily caffeine consumption. It results from the influence of caffeine on the central nervous system in the period of rapid growth and the final stage of brain development, calcium balance and sleep duration. Average daily caffeine consumption in European countries ranging from 280-490 mg. The highest caffeine intake is in Scandinavian countries what results from the great consumption of the coffee. As far as caffeine consumption by Polish population is concerned there is very few data in this subject so far. In the nineties of the previous century it was 141 mg per day, whereas according to recent survey daily caffeine intake by women from the Warsaw region was 251 mg and 15% of examined women consumed an excessive quantity of caffeine (> or = 400 mg). Smokers consume more caffeine than nonsmokers, similarly to persons with mental illnesses. With reference to the caffeine consumption it should be underline that caffeine content in coffee and tea beverages varies greatly depending on the method of brewing whereas the content of caffeine in many brands of energy drinks can much vary. This should be taken into account in the daily caffeine intake. 相似文献
997.
Yano SR Santana VS 《Cadernos de saúde pública / Ministério da Saúde, Funda??o Oswaldo Cruz, Escola Nacional de Saúde Pública》2012,28(5):945-954
This cross-sectional study estimated the prevalence of work days lost due to health problems and associated factors among industrial workers. The study population was a simple random cluster sample of 3,403 workers from 16 to 65 years of age in the city of Salvador, Bahia State, Brazil. Data were collected with individual home interviews. Among industrial workers, one-year prevalence of work days lost to health problems was 12.5%, of which 5.5% were directly work-related and 4.1% aggravated by work. There were no statistically significant differences when compared to other worker categories. Self-perceived workplace hazards, history of work-related injury, and poor self-rated health were associated with work days lost due to work-related injuries/diseases. The findings showed that work days lost are common among both industrial and non-industrial workers, thereby affecting productivity and requiring prevention programs. 相似文献
998.
Nogueira LA Baitelli C Alvarenga RM Thuler LC 《Cadernos de saúde pública / Ministério da Saúde, Funda??o Oswaldo Cruz, Escola Nacional de Saúde Pública》2012,28(5):998-1004
Poor walking performance is predictive of heart disease and osteoporosis and increases the risk of death in the elderly. Gait and vision have been identified as the most valuable physical functions according to multiple sclerosis patients' perceptions. The objective of this study was to perform a translation and cross-cultural adaptation of the Multiple Sclerosis Walking Scale (MSWS-12) into Brazilian Portuguese. A study of cross-cultural adaptation was conducted in ten steps. Participation in the study included four translators, two back-translators, twelve medical experts, twelve patients, twelve healthy subjects, and a Portuguese language expert. Only the question "Did standing make it more difficult to do things?" posed difficulty in the translation process. Maximum time for completion was less than three minutes (171 seconds). Internal consistency analyses showed high reliability (Cronbach's alpha = 0.94). The content validation and internal consistency stages were completed satisfactorily. 相似文献
999.
This study aims to understand the experience of adolescents with cancer, family and the health team regarding death in the healthcare context, in the light of Edgar Morin's proposed theoretical framework of complexity. Participants were 12 adolescents, 14 relatives and 25 health professionals. The interview was used for data collection. The discussion of data was guided by the dialogic life-death in the context of care to adolescents with cancer. It was observed that the singularity in the way the adolescent experiences time and faces death and the possibility that the family will lose a loved one may not be in accordance with the care the health team offers, considering structural, organizational and affective aspects. It is not enough for the team just to rationally make choices on the use of diagnostic-therapeutic devices, in line with predefined moments in the disease. Instead, a contextualized and sensitive understanding of each situation is needed. 相似文献
1000.
Souza DS Ramos AP Nunes FF Moresco V Taniguchi S Leal DA Sasaki ST Bícego MC Montone RC Durigan M Teixeira AL Pilotto MR Delfino N Franco RM Melo CM Bainy AC Barardi CR 《Ecotoxicology and environmental safety》2012,76(2):153-161
Florianópolis, a city located in the Santa Catarina State in southern Brazil, is the national leading producer of bivalve mollusks. The quality of bivalve mollusks is closely related to the sanitary conditions of surrounding waters where they are cultivated. Presently, cultivation areas receive large amounts of effluents derived mainly from treated and non-treated domestic, rural, and urban sewage. This contributes to the contamination of mollusks with trace metals, pesticides, other organic compounds, and human pathogens such as viruses, bacteria, and protozoan. The aim of this study was to perform a thorough diagnosis of the shellfish growing areas in Florianópolis, on the coast of Santa Catarina. The contamination levels of seawater, sediments, and oysters were evaluated for their microbiological, biochemical, and chemical parameters at five sea sites in Florianópolis, namely three regular oyster cultivation areas (Sites 1, 2, and oyster supplier), a polluted site (Site 3), and a heavily polluted site (Site 4). Samples were evaluated at day zero and after 14 days. Seawater and sediment samples were collected just once, at the end of the experiment. Antioxidant defenses, which may occur in contaminated environments in response to the increased production of reactive oxygen species (ROS) by organisms, were analyzed in oysters, as well as organic compounds (in oysters and sediment samples) and microbiological contamination (in oysters and seawater samples). The results showed the presence of the following contaminants: fecal coliforms in seawater samples (four sites), human adenovirus (all sites), human noroviruses GI and GII (two sites), Hepatitis A viruses (one site), JC Polyomavirus in an oyster sample from the oyster supplier, Giardia duodenalis cysts, and Cryptosporidium sp oocysts (one site). Among organochlorine pesticides, only DDT (dichlorodiphenyltrichloroethane) and HCH (hexachlorocyclohexane) were detected in some sediment and oysters samples in very low levels; site 4 had the highest concentrations of total aliphatic hydrocarbons, PAHs, and linear alkylbenzenes (LABs) found either in oysters or in sediment samples. The major concentration of fecal sterol coprostanol was found at site 4, followed by site 3. After 14 days of allocation in the four selected sites, there was a significant difference in the enzymes analyzed at the monitored spots. The detection of different contaminants in oysters, seawater, and sediment samples in the present study shows the impact untreated or inadequately treated effluents have on coastal areas. These results highlight the need for public investment in adequate wastewater treatment and adequate treatment of oysters, ensuring safe areas for shellfish production as well as healthier bivalve mollusks for consumption. 相似文献