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41.
OBJECTIVE: Although breastfeeding is associated with lower rates of a variety of infant illnesses, skeptics have suggested that much of the association is attributable to confounding, even after appropriate statistical adjustment. This article utilizes a novel design to investigate changes in infant illness at the community level after a successful breastfeeding promotion program. METHODS: In this population-based cohort study, the medical records of all infants born in one Navajo community the year before a breastfeeding promotion program (n = 977) and the year during the intervention (n = 858) were reviewed. Outcomes assessed include changes after the intervention in: proportion breastfeeding and/or breastfeeding exclusively; incidence of common infant illnesses in the first year of life; and feeding-group specific incidence of illness. RESULTS: The proportion of women breastfeeding exclusively for any period of time increased from 16.4% to 54.6% after the intervention. The percent of children having pneumonia and gastroenteritis declined 32. 2% and 14.6%, respectively, after the intervention. Feeding-group specific rates of these illnesses were unchanged, indicating that the decline observed was attributable to the increased proportion of infants breastfeeding. In contrast, rates of croup and bronchiolitis increased after the intervention among those fed formula from birth, suggesting a viral epidemic which was limited to those never exclusively breastfed. Finally, sepsis declined in both formula-fed and breastfed infants after the intervention, suggesting that other factors affected this illness outcome after the intervention. CONCLUSIONS: Increasing the proportion of exclusively breastfed infants seems to be an effective means of reducing infant illness at the community level. The experimental design suggests that the increased incidence of illness among minimally breastfed infants is causally related to lack of breast milk, rather than being attributable to confounding.  相似文献   
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PCR-SSCP快速检测耐多药结核分枝杆菌   总被引:1,自引:0,他引:1  
目的:了解本地区结核病耐药基因突变情况,探讨PCR-SSCP作为新的分子药敏试验方法在临床的应用价值。方法:通过提取耐INH、RFP、SM的肺结核患者痰中结核分枝杆菌DNA,进行PCR-SSCP分析,检测结核分枝杆菌rpoB、katG、rpsL基因是否存在突变,并与传统L-J药敏实验对照。结果:30株耐多药株中,耐RPF、INH、SM基因突变阳性率为90%(27/30)、63%(19/30)、53%(16/30)。3个基因联合突变共8株(26.7%),2个基因联合突变共18株(60%),即26株(86.7%)。单基因突变共2株,2株无基因突变。结论:通过PCR-SSCP方法可检测出绝大部分耐多药结核病的耐药基因,rpoB、katG、rpsL基因突变与本地区结核杆菌对RFP、INH、SM耐药性有关。与传统L-J药敏实验对比,PCR-SSCP是一种敏感、快速的指导临床用药的先进检测方法。  相似文献   
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Female circumcision is a traditional practice common in African countries. It involves partial or total removal of external female genitalia. It has led to many complications, in particular, the scarring of the external genitalia. The consequence is a very narrow introitus making the intracavitary brachytherapy treatment component difficult when these women develop cancer of cervix. We present two such cases from our institution. Our aim is to make the radiation and gynecological oncologists, both in developed and developing countries, aware of this practice and the problems they can encounter in the management of such cases. Intracavitary brachytherapy is an important component in the potentially curative role of radiation therapy for cervical cancer. Every effort should be made to ensure that the sequelae of genital mutilation does not deprive these women of the same standard of care as the general population.  相似文献   
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We report the case of a 48-year-old woman operated on for rectal carcinoma and subsequently for metastasis located in three unusual sites (i.e., laryngeal, muscular and cutaneous). Three months after the last surgery, the patient was still alive, without any detectable metastasis.  相似文献   
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We aimed to determine the oxidative stress status in placentas obtained from gestational (GDM) and type 1 (T1D) diabetic pregnancies. Malonaldehyde and protein carbonyls, two biomarkers of oxidative damage, were higher in T1D but not in GDM placentas. Also, higher reduced glutathione and lower oxidized glutathione levels and higher glutathione peroxidase activity were found in T1D but not in GDM placentas. These results suggest that T1D placentas may develop a protective antioxidant mechanism to overcome higher oxidative stress levels.  相似文献   
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Background: In order to better understand the recent rise in nonprescribed use of psychostimulants on college campuses, motives, outcomes, and acceptability of nonprescribed psychostimulants have been evaluated. Despite knowledge that students use nonprescribed medical stimulants for improved academic performance and recreational use, gender differences in these motives have not been examined, despite the fact that the social construction of gender may well affect motives for use. Objectives: The goal of the present study was to examine gender differences in motives, outcomes, and acceptability of nonprescribed psychostimulant use. Methods: 2716 undergraduates (1448 male) between the ages of 17 and 57 years (M = 19.43 years, SD = 1.7 years) completed an online survey examining subjective motives of nonprescribed psychostimulant use, as well as behaviors after use and moral views of nonprescribed use. Results: Consistent with hypotheses and known gender differences in social motivation, results suggested that while females are more likely to use nonprescribed psychostimulants for reasons related to schoolwork, males are typically more likely to use psychostimulants for reasons related to partying and socializing. Additional gender differences were that males are more likely to take part in other risky behaviors after use of psychostimulants, as well as view nonprescribed use as more moral and less physically dangerous than females. Conclusions/Importance: This work suggests that there are striking gender differences in motivation and outcomes of use of nonprescribed psychostimulants, which may have implications for personalized approaches for prevention of nonprescribed psychostimulant use on campuses based on gender.  相似文献   
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