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This study evaluated the genetic variation of 17 autosomal short tandem repeat (STR) loci included in the PowerPlex® 18D Kit. Samples of 562 unrelated healthy Lahu individuals living in Yunnan Province in southwestern China were investigated. The data were analyzed to provide information on allele frequencies and other statistical parameters relevant to the forensic population. Of the 17 loci, 16 reached the Hardy–Weinberg equilibrium after Bonferroni correction. A total of 176 alleles were identified in 17 STR loci, and allele frequencies ranged from 0.000 890 to 0.578 292. The combined discrimination power (CPD) and probability of excluding paternity (CPE) of the 17 STR loci were 0.999 999 999 999 999 999 489 and 0.999 998 301 753 122. The genetic relationships among 28 populations were also estimated.  相似文献   
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ObjectivesTo determine screening outcomes in women who have no recorded risk factors for breast cancer.MethodsA retrospective population-based cohort study included all 1,026,137 mammography screening episodes in 323,082 women attending the BreastScreen Western Australia (part of national biennial screening) program between July 2007 and June 2017. Cancer detection rates (CDR) and interval cancer rates (ICR) were calculated in screening episodes with no recorded risk factors for breast cancer versus at least one risk factor stratified by age. CDR was further stratified by timeliness of screening (<27 versus ≥27 months); ICR was stratified by breast density.ResultsAmongst 566,948 screens (55.3%) that had no recorded risk factors, 2347 (40.9%) screen-detected cancers were observed. In screens with no risk factors, CDR was 50 (95%CI 48–52) per 10,000 screens and ICR was 7.9 (95%CI 7.4–8.4) per 10,000 women-years, estimates that were lower than screens with at least one risk factor (CDR 83 (95%CI 80–86) per 10,000 screens, ICR 12.2 (95%CI 11.5–13.0) per 10,000 women-years). Compared to timely screens with risk factors, delayed screens with no risk factors had similar CDR across all age groups and a higher proportion of node positive cancers (26.1% vs 20.7%). ICR was lowest in screens that had no risk factors nor dense breasts in all age groups.ConclusionsMajority of screens had no recorded breast cancer risk factors, hence a substantial proportion of screen-detected cancers occur in these screening episodes. Our findings may not justify less frequent screening in women with no risk factors.  相似文献   
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《Human immunology》2020,81(9):550-552
We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) alleles by PCR-SSP based typing in 144 Mexicans from the state of Guerrero to obtain information regarding allelic and haplotypic frequencies. We find that the ten most frequent haplotypes in the state of Guerrero include eight Native American and two European haplotypes. Admixture estimates revealed that the main genetic components in the state of Guerrero are Native American (61.36 ± 2.69% by ML; 54.17% of Native American haplotypes) and European (35.01 ± 4.59% by ML; 32.29% of European haplotypes), and a relatively low African genetic component (3.63 ± 2.38% by ML; 5.90% of African haplotypes).  相似文献   
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ObjectiveTo examine differences in lower limb muscle strength between older people with varying degrees of hallux valgus deformity.MethodsMuscle strength was measured at the knee, ankle and foot using hand-held dynamometry and a clinical test of toe strength (the paper grip test) in 157 older people (99 women and 58 men) aged 65 to 91 (mean 74.1, SD 5.9) years. Hallux valgus severity was documented as none, mild, moderate or severe using validated photographs. Differences in muscle strength according to hallux valgus severity were evaluated using analysis of variance, adjusting for age. Paper grip test performance was compared across the hallux valgus severity groups using the chi-square (χ2) statistic.ResultsKnee extension, ankle joint dorsiflexion, ankle joint plantar flexion, ankle joint inversion, ankle joint eversion and lesser toe plantarflexion strength were not significantly different across the four hallux valgus severity groups. However, there was a significant, dose-response reduction in hallux plantarflexion strength with increasing severity of hallux valgus. This persisted after adjustment for age (F3 = 5.5, p = 0.001) with a medium effect size (partial η2 = 0.10). The number of participants who could successfully complete the paper grip test of the hallux significantly reduced across the four hallux valgus categories (χ2 = 18.5, p < 0.001).ConclusionsThere is a specific and progressive reduction in hallux plantarflexion strength with increasing severity of hallux valgus in older people. This finding has potential implications for both the aetiology and treatment of this common and disabling condition.  相似文献   
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《Alzheimer's & dementia》2019,15(12):1507-1515
IntroductionWe estimated the prevalence and correlates of mild cognitive impairment (MCI) among middle-aged and older diverse Hispanics/Latinos.MethodsMiddle-aged and older diverse Hispanics/Latinos enrolled (n = 6377; 50–86 years) in this multisite prospective cohort study were evaluated for MCI using the National Institute on Aging–Alzheimer's Association diagnostic criteria.ResultsThe overall MCI prevalence was 9.8%, which varied between Hispanic/Latino groups. Older age, high cardiovascular disease (CVD) risk, and elevated depressive symptoms were significant correlates of MCI prevalence. Apolipoprotein E4 (APOE) and APOE2 were not significantly associated with MCI.DiscussionMCI prevalence varied among Hispanic/Latino backgrounds, but not as widely as reported in the previous studies. CVD risk and depressive symptoms were associated with increased MCI, whereas APOE4 was not, suggesting alternative etiologies for MCI among diverse Hispanics/Latinos. Our findings suggest that mitigating CVD risk factors may offer important pathways to understanding and reducing MCI and possibly dementia among diverse Hispanics/Latinos.  相似文献   
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The results of cardiovascular autonomic reflex tests on 224 healthy, randomly selected subjects were analysed to study possible sex differences in the autonomic responses. The heart rate response to the Valsalva manoeuvre (Valsalva ratio) was greater in females over 50 years than in males of the same age (1.58 ± 0.34 vs. 1.44 ± 0.30,p < 0.05). The heart rate response to deep breathing (E/I ratio) was higher in females under 50 years than in males under 50 years (1.37 ± 0.17 vs. 1.34 ± 0.18,p < 0.001). The diastolic blood pressure response to isometric handgrip was higher in males under 50 years than in females of the same age (p < 0.05). Although there were sex differences in the magnitude of the responses, the effect of age was similar in males and females and accelerated attenuation of the autonomic responses could not be demonstrated with increasing age. It can be concluded that significant sex differences exist in cardiovascular autonomic responses. The implication of such differences need consideration.  相似文献   
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在这篇文章中,应用圆形分布法计算了泰安市1984—1985两年流行出血热的发病平均日期,分别为1984年11月5号和1985年11月11号,两年合计的平均发病日期为11月9号。另外,还分析了发病的年龄和职业。这将为预防工作提供准确的科学数据。  相似文献   
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Evidence of the effect of exercise on bone loss comes mainly from studies in voluntary postmenopausal women, and no population-based, long-term interventions have been performed. The purpose of this population-based, randomized, controlled trial was to determine the effect of long-term impact exercise on bone mass at various skeletal sites in elderly women with low bone mineral density (BMD) at the radius and hip. Participants ( n =160) were randomly assigned to 30 months either of supervised and home-based impact exercise training or of no intervention. The primary outcome measures were femoral neck, trochanter and total hip BMD, and the secondary outcomes were bone density measures at the radius and calcaneum. Outcomes were assessed at baseline, 12 months and 30 months using blinded operators. The analyses were performed on an intention-to-treat analysis. Mean femoral neck and trochanter BMD decreased in the control group [–1.1%, 95% confidence interval (CI) –0.1% to –2.1% and –1.6%, 95% CI –0.4% to –2.7%], while no change occurred in the exercise group. Mean trochanter BMC decreased more in the control group (–7.7%, 95% CI –9.7% to –5.6% vs. –2.9%, 95% CI –5.3 to –0.9). There were six falls that resulted in fractures in the exercise group and 16 in the control group during the 30-month intervention ( P =0.019). A significant bone loss occurred in both groups at the radius and calcaneum. In multivariate analysis, weight gain was associated with increased BMD and BMC at all femur sites both in the exercise group and in the pooled groups. In conclusion, impact exercise had no effect on BMD, while there was a positive effect on BMC at the trochanter. Exercise may prevent fall-related fractures in elderly women with low bone mass.There was no conflict of interest.  相似文献   
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