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991.
Differences in age of presentation and anatomic risk factors for obstructive sleep apnea (OSA) in Caucasians and African Americans suggest possible racial differences in the genetic underpinnings of the disorder. In this study, we assess transmission patterns in a Caucasian sample consisting of 177 families (N = 1,195) and in an African American sample consisting of 125 families (N = 720) for two variables: 1) apnea hypopnea index (AHI) log transformed and adjusted for age, and 2) AHI log transformed and adjusted for age and body mass index (BMI). We allowed for residual familial correlations and sex-specific means in all models. Analysis of the Caucasian sample showed transmission patterns consistent with that of a major gene that were stronger in the age-adjusted variable than in the age- and BMI-adjusted variable. However, in the African American families, adjusting for BMI in addition to age gave stronger evidence for segregation of a codominant gene with an allele frequency of 0.14, accounting for 35% of the total variance. These results provide support for an underlying genetic basis for OSA that in African Americans is independent of the contribution of BMI.  相似文献   
992.
OBJECTIVE: To examine the feasibility, efficacy, and safety of a structured 12-week exercise training program for a predominantly African-American group of adults with multiple health conditions who reside in difficult social environments. METHODS: A total of 37 females and 7 males (mean age, 54.1 years) participated in an exercise training regimen 3 days per week for 60 minutes per day (cardiovascular, 30 minutes; strength, 20 minutes; and flexibility, 10 minutes). Outcome measures included peak VO(2) (mL min(-1), mL kg(-1) min(-1)); upper and lower body strength (strength); hand-grip strength (GS); body weight (BW); total skin folds (TS); waist-to-hip ratio (WHR); hamstring/low-back flexibility (HLBF); and shoulder flexibility (SF). RESULTS: Compared to the control group, the exercise group showed significant gains in peak VO(2) (p < 0.01); strength (p < 0.01); and body composition (TS, p < 0.01). There was no significant difference between the exercise and control groups on BW, WHR, HLBF, and GS. Of a total 1116 exercise sessions (31 experimental participants x 36 sessions), 87% of the sessions were attended. CONCLUSIONS: A structured exercise-training program can provide substantial improvement in strength and cardiovascular fitness in low-income, sedentary adults with multiple chronic conditions and/or risk factors for chronic conditions. Future research should explore simple home-based and community-based physical activity interventions that provide ongoing support for increasing and maintaining physical activity participation in this cohort.  相似文献   
993.
The aqueous methanol extract (3:1, v/v) of the seeds of Cajanus cajan was investigated for antisickling properties. The extract possessed significant antisickling activity and was found to be concentration-dependent. The kinetics of reversal of presickled erythrocyte (HbSS) cells using the extract at 0.5 mg/mL, 1.0 mg/mL, 1.5 mg/mL, 2.0 mg/mL and 2.5 mg/mL showed first-order kinetics with rate constants of 5.833 x 10(-3) min(-1), 6.143 x 10(-3) min(-1), 5.957 x 10(-3) min(-1) 6.00 x 10(-3) min(-1) and 6.046 x 10(-3) min(-1), respectively, and with an average half-life 115.6 min. Phytochemical screening of the extract revealed the presence of free amino acids, phenolic compounds, tannins, globulins and saponins. These results show that the extract has potential use in the management of painful episodes experienced by sickle cell patients.  相似文献   
994.
Post-menopausal hormonal therapy and gallbladder cancer risk   总被引:3,自引:0,他引:3  
The relation between post-menopausal hormone replacement therapy (HRT) and gallbladder cancer was analyzed in women above age 45 years, using data of a case-control study conducted in Italy between 1985 and 1997, on 31 incident, histologically confirmed cases and 3,702 controls in hospital for acute, non-neoplastic conditions. The multivariate odds ratio (OR) was 3.2 (95% confidence interval: 1.1-9.3) for those who had ever used HRT and the OR tended to rise with longer duration. Although based on small numbers, due to the rarity of the disease, these findings provide the first direct epidemiological evidence of an association between HRT and gallbladder cancer.  相似文献   
995.
Ritter J 《Mycoses》2002,45(Z3):34-38
More than 40 years after its approval, Amphotericin B is still the gold standard in the treatment of invasive fungal infections due to Candida and Aspergillus spp. Three different lipid formulations of Amphotericin B have been available for over 10 years, with only one of them, i.e. liposomal Amphotericin B (Ambisome), approved in Germany. Liposomal Amphotericin B is superior to conventional Amphotericin B due to its reduced nephrotoxicity, the option of a higher initial loading-dose, and fewer infusion-related side-effects, all this with identical or even higher efficacy.  相似文献   
996.
997.
Epidemiological findings indicate that hormonal influences may play a role in the etiology of renal cell cancer (RCC). The possible effect of childbearing remains enigmatic; while some investigators have reported a positive association between number of births and renal cell cancer risk, others have not. A case-control study, nested within a nation-wide Fertility Register covering Swedish women born 1925 and later, was undertaken to explore possible associations between parity and age at first birth and the risk of renal cell cancer. Among these women a total of 1465 cases of RCC were identified in the Swedish Cancer Register between 1958 and 1992 and information on the number of live childbirths and age at each birth was obtained by linkage to the Fertility Database. For each case, five age-matched controls were randomly selected from the same register. Compared to nulliparous women, ever-parous women were at a 40% increased risk of RCC (Odds Ratio [OR]=1.42; 95% CI 1.19-1.69). The corresponding OR for women of high parity (five or more live births) was 1.91 (95% CI 1.40-2.62). After controlling for age at first birth among parous women, each additional birth was associated with a 15% increase in risk (OR=1.15; 95% CI 1.08-1.22). The observed positive association between parity and renal cell cancer risk is unlikely to be fully explained by uncontrolled confounding, but warrants further evaluation in large studies, with allowance for body mass index.  相似文献   
998.
Both parity and a young age at first pregnancy are associated with a reduction in breast cancer risk. The hormones involved in this process are not fully investigated. Human chorionic gonadotropin is a placental hormone, which in rats and in human breast cells in vitro has been shown to prevent against breast cancer. Hyperemesis, a severe nausea combined with vomiting during pregnancy, is associated with increased levels of human chorionic gonadotropin. We investigated the possible relationship between hyperemesis and subsequent breast cancer risk in a case-control study based on registry data. Among 13 079 breast cancer cases and 34 348 individually matched controls we found 148 cases and 405 controls who had been hospitalised for hyperemesis. Hyperemesis was not associated with breast cancer risk (adjusted odds ratio 1.05, 95% confidence interval 0.86-1.27), and similar risks were observed regardless of age at diagnosis, number of hospitalisations for hyperemesis or time of follow-up. Our results do not support the hypothesis that human chorionic gonadotropin is responsible for the protective effect of pregnancies upon breast cancer risk.  相似文献   
999.
Most multicenter randomized AML studies use randomizations of patients early or later in complete remission which necessarily occur with exclusions and positive selection of patients included. Since the exclusion criterias are regimen related and do not follow common standards, incomparabilities between treatment results across different studies are produced by these late randomizations. In order to overcome this problem, we here propose a cooperation of studies on the basis of a general up-front randomization with attribution of 10% patients from each study to a common standard arm. A validation of complete treatment strategies according to intent-to-treat against the standard arm and thus also across the studies is provided by this inter-group model which may contribute to accelerate the therapeutic progress in AML.  相似文献   
1000.
Studies of the relationship between the fragile X (FRAXA) mutation and autism have been controversial. Although there are differences between the two populations, individuals with FRAXA and autism exhibit remarkably similar aberrant behavior patterns. We examined comparably aged children and adolescents with FRAXA or autism to determine whether longitudinal changes in cognitive ability and adaptive behavior were similar in the two groups. We found decreases in IQ scores in young children with FRAXA as well as in those with autism. Declines in IQ scores were steeper among children with FRAXA. Older children and adolescents with autism exhibit stable test-retest scores, whereas older children with FRAXA continue to show decreases. Comparable declines in adaptive behavior composite scores were observed in both groups, at all ages tested, and across all adaptive behavior domains.  相似文献   
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