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1.
This study uses data from a population-based survey to examine the fertility schedules of 704 women in a rural district of Malawi. The main objective is to assess self-reported fecundity status as a measure of fertility impairment. Life tables are used to examine the timing and tempo of births for women reporting difficulty getting pregnant as compared to women with no reported fecundity difficulties. Results of the analysis indicate that women with self-reported fecundity difficulties are older at each birth and have longer median birth intervals than do women with no reported difficulties. Cox proportional hazards models show that the report of a difficulty getting pregnant is significantly associated with at least a 30% lower likelihood of a first, second, or third birth. The relationships are not modified when accounting for demographic characteristics, previous sexual behaviors, or STI status.  相似文献   
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BACKGROUND: The most recent major U.S. trials that evaluated community-level programs to influence risk factors and health behaviors identified secular trends in the risk factors and health behaviors among the factors that might have limited community-level effects. The research reported in this paper uses data from one of the trials to examine the secular trend explanation directly. METHODS: Data from the 22-community Community Intervention Trial for Smoking Cessation (COMMIT) were analyzed to test a hypothesis based on secular trend reasoning: program effects for smoking prevalence were larger for treatment communities matched to control communities with small declines in smoking than in treatment communities matched to control communities with larger declines in smoking. RESULTS: Consistent with the secular trend explanation, program effects were larger when control communities had relatively small declines in smoking prevalence. CONCLUSIONS: The findings suggest that secular trends masked community-level program effects in COMMIT.  相似文献   
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Knowledge concerning patterns of health care utilization among Latino-adolescent immigrants is needed to develop culturally-appropriate programs. The objectives of this study were to estimate the annual prevalence of having had a routine physical exam and episodes of adolescents’ not seeking health care when they thought they should (forgone health care) among Latino adolescents by immigrant-generational status. Cross-sectional analysis of data from Latino adolescents in Wave I of the National Longitudinal Adolescent Health Study. First-generation immigrants who had lived in the U.S. ≤ 5 years were less likely to receive routine care than third-generation immigrants (39.0% vs. 54.9%). This disparity decreased after adjustment for insurance status, parental education and poverty among Mexican origin adolescents. On average, 16.0% of first-generation immigrants who had lived in the U.S. ≤ 5 years and 22.5% of third-generation immigrants reported forgoing health care. After adjustment for age, insurance status, parental education and routine care, recent arrivals were less likely than third-generation immigrants to forgo health care. Recent arrivals were less likely to receive a routine physical exam and to forgo care than third-generation immigrants. Future studies should explore the effect of acculturation on knowledge, beliefs and perceptions about health, illness and care-seeking behaviors.  相似文献   
5.

Background

Evaluation of stable symptomatic outpatients with suspected coronary artery disease (CAD) may be challenging because they have a wide range of cardiovascular risk. The role of troponin testing to assist clinical decision making in this setting is unexplored.

Objectives

This study sought to evaluate the prognostic meaning of single-molecule counting high-sensitivity troponin I (hsTnI) (normal range <6 ng/l) among outpatients with stable chest symptoms and suspected CAD.

Methods

Participants with available blood samples in PROMISE (Prospective Multicenter Imaging Study for Evaluation of Chest Pain) were studied, and hsTnI results were analyzed relative to the primary outcome of death, acute myocardial infarction (MI), or hospitalization for unstable angina by 1 year. The secondary outcome was the composite of cardiovascular death or acute MI.

Results

The study sample consisted of 4,021 participants; 98.6% had measurable hsTnI concentrations. The median hsTnI value was 1.6 ng/l. In upper hsTnI quartiles, patients had higher-risk clinical profiles. Higher hsTnI concentrations were associated with greater event probabilities for death, acute MI, or hospitalization for unstable angina. In multivariable models, hsTnI concentrations independently predicted death, acute MI, or hospitalization for unstable angina (hazard ratio: 1.54 per increase in log-hsTnI interquartile range; p < 0.001) and cardiovascular death or acute MI (hazard ratio: 1.52 per increase in log-hsTnI interquartile range; p < 0.001) and were particularly associated with near-term events, compared with longer follow-up.

Conclusions

In symptomatic outpatients with suspected CAD, higher concentrations of hsTnI within the normal range were associated with heightened near-term risk for death, acute MI, or hospitalization. (Prospective Multicenter Imaging Study for Evaluation of Chest Pain [PROMISE]; NCT01174550)  相似文献   
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Fibromas are benign tumors that are composed of fibrous or connective tissue. They can grow in all organs, arising from mesenchymal tissue (a type of loose connective tissue). The term “fibroblastic” or “fibromatous” is used to describe tumors like the fibroma. This 69-year-old male presented to us with giant, multiple, very slowly progressive, painless, noninflammatory, soft, trans-illuminant, pedunculated lid swellings with a two decade history. There were no other swellings on the body. He was clinically normal on systemic examination except for the immature cataracts in both eyes. The diagnosis was confirmed on histopathology. Simple excision removed all the soft fibromas virtually leaving no scar. A review of literature world-wide using Medline Plus/PubMed revealed this to be the only reported case of multiple giant soft fibromas of the lid.  相似文献   
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Young women in South Africa are at high risk for HIV infection. Cash transfers offer promise to reduce HIV risk. We present the design and baseline results from HPTN 068, a phase III, individually randomized trial to assess the effect of a conditional cash transfer on HIV acquisition among South African young women. A total of 2533 young women were randomized to receive a monthly cash transfer conditional on school attendance or to a control group. A number of individual-, partner-, household- and school-level factors were associated with HIV and HSV-2 infection. After adjusting for age, all levels were associated with an increased odds of HIV infection with partner-level factors conveying the strongest association (aOR 3.05 95 % CI 1.84–5.06). Interventions like cash transfers that address structural factors such as schooling and poverty have the potential to reduce HIV risk in young women in South Africa.  相似文献   
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BACKGROUND: Patients with recessive dystrophic epidermolysis bullosa (RDEB) are at high risk of developing squamous cell carcinoma on or after midadolescence, and most patients die of metastatic squamous cell carcinoma within 5 years of diagnosis of their first squamous cell carcinoma. OBJECTIVE: We sought to determine whether isotretinoin can be safely administered to patients with RDEB as a possible chemopreventive agent. METHODS: A total of 20 patients with RDEB aged 15 years or older were treated daily for 8 months with isotretinoin (with a targeted dosage of 0.5 mg/kg/d). RESULTS: No unusual adverse reactions were noted in this patient population. Several patients experienced reduced blistering at lower doses and increased mechanical fragility at maintenance dosage. CONCLUSIONS: Isotretinoin, at least up to a dosage of 0.5 mg/kg/d, may be safely used in patients with RDEB. Although increased fragility may occur, patients tolerated this drug well and were receptive to its long-term use for possible chemoprevention of cancer. Whether such an effect will occur is yet to be proven.  相似文献   
10.
Assessment of usual dietary intake of a population is essential to understand the nutrition status of the population. Methods like 24-hour dietary recall and food records are commonly used for this task. However, within-individual variation exists in the food record data. Methods considering measurement errors have been used to evaluate the association between nutrient intakes and diseases. Few have been devoted to estimating the distribution of usual daily intakes. This paper proposes applying the formulation of the overdispersed exponential family to estimate the distribution of usual nutrient intake and applies the adjustments developed by Liu to reduce the variance of the distribution. The proposed method has the advantages of working on the original scale of data and implementation convenience. The adjustment of the variance is carried out by dividing the variance into within-individual variance and among-individual variance. The adjusted variance, then, is used to estimate the distribution of the usual daily intake. Sampling weights are considered in all the steps, except the estimation of the ratio of within to among variance. The data for this study are from the Nutritional and Health Survey in Taiwan conducted between 1993 and 1996 (NAHSIT, 1993-1996). An independent external set of data for people aged between 18 and 28 years (49 males and 20 females) is used to estimate the ratio of within to among individual variance. Due to the availability of data in estimating the ratio of within to among individual variance, 430 males and 422 females in the NAHSIT sample are used to estimate the distribution of usual daily intakes for people aged between 18 and 28 in Taiwan. The distribution also allows us to estimate the proportion of people who do not meet the recommended daily nutrient allowance (RDNA). The results show that the intakes of calcium and vitamin E of this group of people fall far below RDNA.  相似文献   
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