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1.
ObjectivesTo explore the relationships among potentially modifiable factors related to childbirth and effective breastfeeding initiation at approximately 36 hours after birth and duration and exclusivity at hospital discharge, 2 weeks, 2 months, and 6 months after birth in primiparous women and to explore whether modifiable and nonmodifiable secondary factors and covariates influenced the relationships among factors related to childbirth and these breastfeeding outcomes.DesignA prospective, longitudinal, cohort study.SettingThe postpartum units of two general hospitals in eastern Canada.ParticipantsNinety-seven mother–infant dyads.MethodsWe recorded demographic, childbirth, obstetric history, and breastfeeding data through chart review. A breastfeeding observation was completed at approximately 36 hours after birth by unit nurses. Participants maintained breastfeeding logs in hospital and for 6 months after birth and completed three self-report questionnaires before discharge. We analyzed outcomes using backward stepwise linear and logistic regression.ResultsOne childbirth factor, labor induced with oxytocin, was negatively associated with effective initiation of breastfeeding, and none was related to breastfeeding duration and exclusivity at any time point. Maternal weight; professional support; and newborn’s gestational age at birth, 5-minute Apgar score, weight loss, LATCH score, and active feeds (newborn actively suckled at the breast) were significantly associated with breastfeeding outcomes.ConclusionInduction of labor with oxytocin should be used judiciously; when used, nurses must be hypervigilant to assess the mother–infant dyad for breastfeeding issues and to intervene to prevent or remediate them.  相似文献   
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BACKGROUND: In patients with chronic kidney disease (CKD), although strong associations have been observed between malnutrition and atherosclerosis, the relationship between serum albumin concentration and angiographic changes of coronary artery disease (CAD) remains poorly explored. The goal of the present study was, in patients with CKD, to clarify the relationship between the angiographic severity of CAD and serum albumin concentration reflecting either inflammation or nutrition or both. METHODS: In this study, 100 end-stage renal disease (ESRD) patients were enrolled, who commenced long-term dialysis therapy at our hospital and underwent coronary angiography within 3 months of the first haemodialysis (HD) session. Mean age was 63+/-11 years, 20% of the subjects were female and 62% had diabetes. Severity of CAD was evaluated in terms of (i) number of vessels exhibiting CAD (>or=75% stenosis) and (ii) Gensini score (GS). Clinical characteristics and laboratory findings were recorded at initiation of long-term HD therapy. We then evaluated a possible association with the presence and degree of CAD. RESULTS: Sixty-four patients exhibited signs of CAD. Forty-one among them (64%) had multivessel disease. On univariate logistic regression analysis, age, diabetes and hypoalbuminaemia were significantly associated with multivessel CAD. Univariate linear regression analysis demonstrated a positive correlation of age and diabetes with GS, and an inverse correlation of BMI and serum albumin level with GS. Stepwise regression analysis showed age and serum albumin level to be independently associated with multivessel CAD and GS. The ROC curves demonstrated best cut-off levels of age and albumin for predicting multivessel CAD to be 70 years and 3.15 g/dl, respectively. CONCLUSION: Hypoalbuminaemia at the initiation of dialysis is an important predictor of advanced CAD, particularly in male and in diabetic patients. It may reflect mainly a state of inflammation. However, malnutrition as a confounding factor cannot be entirely excluded.  相似文献   
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目的 探讨失眠症患者对睡眠质量的主观评估,并通过对多导睡眠图(PSG)睡眠参数的定量分析,对失眠症患者的睡眠状况进行客观评估,进一步将二者进行对比分析.方法 对失眠症患者和健康人各100例运用匹兹堡睡眠质量指数问卷(PSQI)进行评定,并分别进行多导睡眠图的整夜睡眠描记,次日晨起后询问夜间睡眠情况.结果 失眠症组PSQI各成分得分及总分均高于对照组,差异有统计学意义(P<0.01).与对照组相比,失眠症组的睡眠潜伏期(min)延长(失眠症组43.69±11.54,对照组16.01±10.44)、总睡眠时间(min)减少(失眠症组314.65±91.89,对照组446.41±77.81)、睡眠效率降低(失眠症组64.51%±18.59%,对照组91.32%±3.58%)、快眼动睡眠时间(min)减少(失眠症组33.26±15.61,对照组93.21±21.63),差异有统计学意义(P<0.01).失眠症组对总睡眠时间的评估较PSG检测值显著减低、对睡眠潜伏期的评估较PSG检测值显著增高,自我评估与实际睡眠情况不一致.结论 失眠症患者睡眠质量较差.失眠症患者的PSG各睡眠参数有特征性的改变,利用PSG检查发现失眠症患者对失眠情况的主客观评估不一致,存在过高估价睡眠潜伏期和过低估价睡眠时间的倾向.  相似文献   
5.
More than wisdom     
This paper presents and interprets empirical findings from field studies in a Bambara village in the Republic of Mali in order to place the traditional position of the elderly in cultural context. The significance of a seniority principle underlying the social structure of African society is emphasized. Thus attitude and behavioral changes which affect the status of the elderly have wider ramifications for the society as a whole. Attention centers on the role of age sets, myth and ritual, ancestor worship and socialization practices as elements of a total cultural system in which the rules of seniority provide an organizing force. In the last section, the ways in which social change threatens the viability of a social system governed by the seniority principle are reviewed. Signs of breaks in the solidarity of the traditional community are noted. Finally, two strategies for improving the position of the elderly in the African countryside as the traditional system disintegrates are proposed.To the people of Sonongo in gratitude.  相似文献   
6.
ART技术封闭恒牙的3年临床效果观察   总被引:4,自引:1,他引:3  
目的 :评价非创伤性充填 (ART)技术对恒牙窝沟封闭后 ,封闭剂保留及新生龋病发生情况。方法 :1996年在四川省德阳市 4所中学选取 12~ 13岁儿童 14 0名作 191个ART封闭。采用WHO的ART标准器械 ,德国ESPE公司生产的高强度玻璃离子材料 ,对选择的牙面窝沟进行封闭 ;操作者为经中等口腔专业训练的医生。试验 3年后对ART封闭及牙龋病情况进行评价。结果 :封闭后 1、2、3年的封闭成功率分别为 89.6% ,78.8% ,71.9%。试验后 1年没有新生龋齿的发生 ,试验后 2、3年 ,龋患率较低 ,分别为 1.6% ,2 .8%。结论 :ART封闭试验 3年的保存率较高 ,新生龋发生率低 ;作为恒牙龋病防治的措施是适合和可接受的 ;是一种适合于在学校、社区开展的有效、实用的龋病预防方法。  相似文献   
7.
Stigma is a recognised problem for effective prevention, treatment, and care of HIV/AIDS. However, few studies have measured changes in the magnitude and character of stigma over time. This paper provides the first quantitative evaluation in Africa of the changing nature of stigma and the potential determinants of these changes. More specifically, it evaluates the dynamic relationship between stigma and (1) increased personal contact with people living with HIV/AIDS and (2) knowing people who died of AIDS. Panel survey data collected in Cape town 2003 and 2006 for 1074 young adults aged 14–22 years were used to evaluate changes in three distinct dimensions of stigma: behavioural intentions towards people living with HIV/AIDS; instrumental stigma; and symbolic stigma. Individual fixed effects regression models are used to evaluate factors that influence stigma over time. Each dimension of stigma increased in the population as a whole, and for all racial and gender sub-groups. Symbolic stigma increased the most, followed by instrumental stigma, while negative behavioural intentions showed a modest increase. Knowing someone who died of AIDS was significantly associated with an increase in instrumental stigma and symbolic stigma, while increased personal contact with people living with HIV/AIDS was not significantly associated with any changes in stigma. Despite interventions, such as public-sector provision of antiretroviral treatment (which some hoped would have reduced stigma), stigma increased among a sample highly targeted with HIV-prevention messages. These findings emphasise that changes in stigma are difficult to predict and thus important to monitor. They also indicate the imperative for renewed efforts to reduce stigma, perhaps through interventions to weaken the association between HIV/AIDS and death, to reduce fear of HIV/AIDS, and to recast HIV as a chronic manageable disease.  相似文献   
8.
OBJECTIVES: Damage mechanics has been defined as the study of the initiation (initial failure) and accumulation of damage to and including rupture (final failure). This study was designed to evaluate the effect of increasing fiber-reinforced composite (FRC) substructure within a standardized fixed partial denture (FPD) model on the failure performance, in terms of damage mechanics. METHODS: The two FRC restorative systems, Targis/Vectris (TV) (Ivoclar Vivadent) and EverStick (ES) (Stick Tech with Gradia, GC Corp.), were used to restore the molar FPD model (1.5 mm axial and 2.0 mm occlusal reduction). Templates were used to standardize substructure designs with 0, 18, 43, and 66% cross-sectional FRC volume fraction (V(FRC)) of fiber substructure. Specimens (n = 5) were homogenized at 29 points and stored for 1 week at 37 degrees C in distilled water. Specimens were luted with calcium hydroxide, then statically loaded until failure. Initial failure (IF), final failure (FF) and the mode of failure were recorded. RESULTS: The lowest mean load to initial failure was 530 N (TV 18%) and the highest was 1208 N (ES 66%). Linear regression analysis calculated the Pearson's correlation coefficient (r) for the interactions between V(FRC) and IF (ES: r = 0.7879, TV: r = 0.6184), V(FRC) and FF (ES: r = 0.912, TV: r = 0.8152), and between IF and FF (ES: r = 0.892, TV: r = 0.7237). Unreinforced specimens universally fractured instantaneously. SIGNIFICANCE: The highest loads to initial and final failure were yielded by specimens with the highest cross-sectional V(FRC).  相似文献   
9.
Immunoglobulin mimicry by Hepatitis C Virus envelope protein E2   总被引:4,自引:0,他引:4  
Hu YW  Rocheleau L  Larke B  Chui L  Lee B  Ma M  Liu S  Omlin T  Pelchat M  Brown EG 《Virology》2005,332(2):538-549
Hepatitis C virus (HCV) establishes persistent infection in the majority of infected individuals. The currently accepted hypothesis of immune evasion by antigenic variation in hypervariable region 1 (HVR1) of glycoprotein E2 does not however, explain the lack of subsequent immune recognition. Here, we show that the N-terminal region of E2 is antigenically and structurally similar to human immunoglobulin (Ig) variable domains. E2 is recognized by anti-human IgG antibodies and also possesses common amino acid (aa) sequence features of the conserved v-gene framework regions of human Ig light chains in particular but also heavy chains and T cell receptors. Using a position specific scoring system, the degree of similarity of HVR1 to Ig types correlated with immune escape and persistence in humans and experimentally infected chimpanzees. We propose a unique role for threshold levels of Ig molecular mimicry in HCV biology that not only advances our concept of viral immune escape and persistent infection but also provides insight into host-dependent disease patterns.  相似文献   
10.
Human oocytes isolated from healthy non-preovulatory antralfollicles which had not been stimulated spontaneously resumedmeiosis at a low rate (31%) when compared with those from atreticfollicles (73%). Human follicular fluid did not inhibit spontaneousmaturation of rat oocytes in vitro, regardless of the qualityor maturity of the follicle or the treatment of the patient.In the human, oocyte maturation may involve a stimulatory processas well as a removal of inhibition.  相似文献   
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