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Defining con-founders that affect the reliability of diagnostic tests for coronavirus disease 2019 is vital to breaking the chain of infection. The elderly population is a higher risk group for the emerging virus. However, gender seems to exert a critical role in modifying the infection risk among women owing to hormonal changes. The menopause transition is an exceptional period for older women where the protective and immunomodulatory effects of the estrogen hormone are lost. Accordingly, attention should be given to postmenopausal women since they will have an increased risk compared to their pre-menopausal peers. 相似文献
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Platelets are needed to prevent or arrest bleeding and aggregate at the site of injury upon vascular damage. Platelets express receptors for estrogens which might affect the function of the platelets and their hemostatic ability. The aim was to identify possible differences in platelet function related to age, gender, and phases of the menstrual cycle by use of impedance aggregometry with Multiplate. In the first part of the study, platelet function was assessed in 60 healthy individuals (30 men and 30 women) in each of three age groups (20–25, 40–45, and 60–65 years). In the second part of the study, the platelet function was analyzed on four occasions during the menstrual cycle in women without oral contraceptives (OCs) (n = 17) and compared to 19 women on OCs and 18 men of similar age (20–40 years). For the women on OCs, aggregation was analyzed once during the tablet-free week and once late during the period with OCs. The men were sampled once. Women of younger age (<45 years) had significantly higher agonist-induced aggregation response than both men and post-menopausal women (60–65 years). The agonist-induced aggregation response did not differ between phases of the menstrual cycle or OC use. The results suggest that estradiol and/or progesterone affect spontaneous aggregation since it was found to be lowest in the mid-luteal phase. Spontaneous aggregation was significantly lower in women on OCs than in both men and women without OCs. Our findings indicate that fertile age is associated with higher aggregation response capacity of the platelets, possibly to prevent excessive bleeding during menstruation, but this response capacity is not altered during the menstrual cycle or by use of OCs. 相似文献
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目的 通过观察早产儿不同胎龄Toll样受体9(TLR9)的表达,探讨早产儿免疫功能低下的机制。方法 采集2010年7月至2014年6月在上海市嘉定区妇幼保健院产科出生的活产新生儿的脐血229份,按胎龄分为4组,28~31周组,31~34周组,34~37周组,≥37周组,采用流式细胞术和实时荧光定量PCR方法,分别检测其TLR9的蛋白和mRNA表达情况,了解其与胎龄之间的关系,并分析mRNA和蛋白表达间的相关性。结果 TLR9阳性细胞率在28~31周组,31~34周组,34~37周组,≥37周组分别为(15.93±6.23)%,(11.63±6.70)%,(13.66±6.88)%,(20.51±12.06)%;其在胎龄28~31周较高,至31~34周逐渐下降至最低,两组差异有统计学意义(P<0.05);34~37周后TLR9阳性细胞率表达逐渐升高,至≥37周达最高,两胎龄组比较,差异具有统计学意义(P<0.05)。31~37周间新生儿脐血TLR9阳性细胞率与胎龄呈正相关(r=0.273,P=0.006)。TLR9 mRNA表达在28~31周组,31~34周组,34~37周组,≥37周组分别为(4.95±3.44)%,(8.89±8.49)%,(13.91±10.92)%,(7.19±7.11)%;其在28~36周逐渐升高,与胎龄呈正相关(r=0.355,P< 0.001)。≥37周TLR9 mRNA表达量下降,该值虽高于28~31周,但差异无统计学意义(P>0.05)。相关性分析表明,同胎龄时期同样本新生儿的TLR9 mRNA和TLR9阳性细胞率之间存在负相关(r=-0.227,P=0.011)。结论 TLR9阳性细胞率和TLR9 mRNA表达在不同胎龄组新生儿间有差异,TLR9阳性细胞率表达在31~37周间随着胎龄的增加而增加,TLR9 mRNA在28~36周间随着胎龄的增加而增加。 相似文献
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Many studies have reported age-associated DNA methylation changes and age-predictive models in various tissues and body fluids. Although age-associated DNA methylation changes can be tissue-specific, a multi-tissue age predictor that is applicable to various tissues and body fluids with considerable prediction accuracy might be valuable. In this study, DNA methylation at 5 CpG sites from the ELOVL2, FHL2, KLF14, C1orf132/MIR29B2C, and TRIM59 genes were investigated in 448 samples from blood, saliva, and buccal swabs. A multiplex methylation SNaPshot assay was developed to measure DNA methylation simultaneously at the 5 CpG sites. Among the 5 CpG sites, 3 CpG sites in the ELOVL2, KLF14 and TRIM59 genes demonstrated strong correlation between DNA methylation and age in all 3 sample types. Age prediction models built separately for each sample type using the DNA methylation values at the 5 CpG sites showed high prediction accuracy with a Mean Absolute Deviation from the chronological age (MAD) of 3.478 years in blood, 3.552 years in saliva and 4.293 years in buccal swab samples. A tissue-combined model constructed with 300 training samples including 100 samples from each blood, saliva and buccal swab samples demonstrated a very strong correlation between predicted and chronological ages (r = 0.937) and a high prediction accuracy with a MAD of 3.844 years in the 148 independent test set samples of 50 blood, 50 saliva and 48 buccal swab samples. Although more validation might be needed, the tissue-combined model’s prediction accuracies in each sample type were very much similar to those obtained from each tissue-specific model. The multiplex methylation SNaPshot assay and the age prediction models in our study would be useful in forensic analysis, which frequently involves DNA from blood, saliva, and buccal swab samples. 相似文献
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《中国现代医生》2020,58(31):130-133+141
目的 研究产褥感染的危险因素及常见致病微生物耐药情况,为临床治疗提供参考。方法 回顾性分析我院2017 年1 月~2019 年12 月发生的84 例产褥感染病例的临床资料,与同时期未发生产褥感染的200 例产妇进行对照研究,分析产褥感染的影响因素,并对分离获得的致病微生物进行耐药性分析。结果 感染组妊娠糖尿病、产钳助产、宫口开全后中转剖宫产患者的分布率高于对照组,差异有统计学意义(P<0.05);经多因素Logistic 回归分析,妊娠糖尿病是产褥感染的独立影响因素(P<0.05)。本研究中共检出致病微生物40 株,其中革兰阴性菌13 株(占32.50%),革兰阳性菌10 株(占25.00%),支原体16 株(占40.00%),衣原体1 株(占2.50%),革兰阴性菌中以大肠埃希菌最常见,对二代头孢菌素类抗生素耐药率20%。革兰阳性菌以金黄色葡萄球菌最常见,对青霉素及头孢菌素耐药率高,未发现对亚胺培南及万古霉素耐药。结论 产钳助产、妊娠糖尿病、宫口开全后中转剖宫产是产褥感染可能的危险因素,其中,妊娠糖尿病是产褥感染的独立危险因素。目前临床常见致病微生物谱及耐药率未发生明显变化。 相似文献