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71.
72.

Objectives

We aimed to evaluate the relationship between baseline renal function and changes in telomere length in Han Chinese.

Methods

The telomere restriction fragment (TRF) length of leukocytes in the peripheral blood was measured in healthy volunteers recruited in 2014. The estimated glomerular filtration rate (eGFR) was calculated based on serum creatinine (Scr) and serum cystatin C (CysC)-eGFRcys and eGFRScr-cys through the Cockcroft-Gault formula (eGFRC-G) or the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI / eGFRCKD-EPI) equation. The correlation between telomere length changes over time and renal function was analyzed.

Results

Leukocyte TRF lengths were negatively correlated to age (r = -0.393, p < 0.001) and serum CysC (r = -0.180, p < 0.01), while positively associated with eGFRCKD-EPI, eGFRC-G, eGFRcys, and eGFRScr-cys (r = 0.182, 0.122, 0.290, and 0.254 respectively, p < 0.01). The 3-year change of telomere length was 46 bp/years. When adjusted for age, the associations between telomere length changes and baseline, subsequent TRF lengths, and serum CysC were no longer present. No association was observed between TRF length changes and renal function.

Conclusion

The rate of telomere length changes was affected by age and baseline telomere length. The telomere length changes might be important markers for aging.
  相似文献   
73.
Objective: The objective of this study was to answer three questions: (1) Is perceived discrimination adversely related to self-rated stress via the social capital and health care system distrust pathways? (2) Does the relationship between perceived discrimination and self-rated stress vary across race/ethnicity groups? and (3) Do the two pathways differ by one’s race/ethnicity background?

Design: Using the Philadelphia Health Management Corporation’s Southeastern Pennsylvania Household Survey, we classified 9831 respondents into 4 race/ethnicity groups: non-Hispanic White (n?=?6621), non-Hispanic Black (n?=?2359), Hispanic (n?=?505), and non-Hispanic other races (n?=?346). Structural equation modeling was employed to simultaneously estimate five sets of equations, including the confirmatory factor analysis for both social capital and health care distrust and both direct and indirect effects from perceived discrimination to self-rated stress.

Results: The key findings drawn from the analysis include the following: (1) in general, people who experienced racial discrimination have higher distrust and weaker social capital than those without perceived discrimination and both distrust and social capital are ultimately related to self-rated stress. (2) The direct relationship between perceived discrimination and self-rated stress is found for all race/ethnicity groups (except non-Hispanic other races) and it does not vary across groups. (3) The two pathways can be applied to non-Hispanic White and Black, but for Hispanic and non-Hispanic other races, we found little evidence for the social capital pathway.

Conclusions: For non-Hispanic White, non-Hispanic Black, and Hispanic, perceived discrimination is negatively related to self-rated stress. This finding highlights the importance of reducing interpersonal discriminatory behavior even for non-Hispanic White. The health care system distrust pathway can be used to address the racial health disparity in stress as it holds true for all four race/ethnicity groups. On the other hand, the social capital pathway seems to better help non-Hispanic White and Black to mediate the adverse effect of perceived discrimination on stress.  相似文献   
74.
目的:观察蓝布正提取物(GHE)对血管性痴呆(VD)大鼠学习记忆能力的影响并探讨其作用的机制。方法:采用双侧颈总动脉结扎法制作VD大鼠模型,将大鼠随机分成假手术组,模型组,GHE高、中、低剂量组(7,3.5,1.75 g·kg~(-1))和阳性药组(天保宁银杏叶片,0.007 g·kg~(-1)),各组灌胃相应药物,每日1次,连续35 d,在第30~35天进行Morris水迷宫实验检测大鼠的学习记忆能力,Morris水迷宫实验结束后处死大鼠,收集大脑样本,免疫组化法检测海马CA1区B细胞淋巴瘤-2(Bcl-2)相关X蛋白(Bax),Bcl-2,神经营养因子-3(NT-3),脑源性神经营养因子(BDNF)蛋白表达。结果:与模型组比较,GHE高、中剂量组可明显缩短大鼠的逃避潜伏期,增加穿越平台数(P0.05);GHE高、中、低剂量组可显著降低海马CA1区Bax表达,升高Bcl-2,NT-3,BDNF表达(P0.05,P0.01)。结论:GHE能改善VD大鼠的学习记忆能力,其机制可能与促进海马CA1区NT-3,BDNF的表达,抑制神经细胞凋亡有关。  相似文献   
75.
楔状缺损的生物力学探讨   总被引:23,自引:10,他引:23  
  相似文献   
76.
DF暂封糊剂的研制   总被引:2,自引:1,他引:2  
目的:研制一种单组份、糊剂型、水硬性暂封材料。方法:通过测定材料在水中的凝固速度及凝固后材料表面性状,对水硬性材料成份的种类、赋形剂的种类及凝固促进剂的种类进行筛选。结果:水硬性材料A2的凝固速度最快,赋形剂B2的效果最好,凝固促进剂C1的作用优于C2。结论:采用A2、B2、C1作为暂封材料基本组成效果最佳,凝固24h后抗压强度达13.94MPa±2.07MPa。  相似文献   
77.
Fan B  Yang J  Gutmann JL  Fan M 《Journal of endodontics》2008,34(11):1337-1341
The purpose of this study was to investigate the morphology of the radicular grooves and root canal cross-sections in mandibular first premolars that exhibit a C-shaped root. Eighty-six mandibular first premolars with C-shaped roots were scanned from the coronal to anatomical apex using microCT80. The location, length, and depth of the radicular grooves were measured. The cross-sectional morphology of root canal systems was evaluated at 11 levels. Results were subject to the Kruskal-Wallis test. Of the 86 C-shaped roots, a total of 93 radicular grooves were noted. Most of the grooves (78.5%) were located on the mesiolingual surface of the root. The C-shaped canal could vary considerably in shape at different levels, and the incidence of two canals at the middle and apical was 21% and 80%, respectively. This study shows that radicular grooves may present relevant morphologic variations in the root canal system when the C-shaped root is present.  相似文献   
78.
We divided healthy newborns (aged between 2 weeks and 6 months) into four groups, less than 2 weeks old, 60 +/- 7 days, 120 +/- 7 days, and 180 +/- 7 days, between June 2001 and February 2002, and each group had 40 infants. The lineal distances included 13 items related to the nose, mouth, and lips.The average width of the columella at the midpoint was 3.2, 3.5, 3.7, and 3.8 mm for the 2-week-old group, the 2-month-old group, the 4-month-old group, and the 6-month-old group, respectively. The average height of the columella was 4.7, 4.9, 5.2, and 5.3 mm. The average length between the medial alar bases was 13.7, 14.4, 17.4, and 17.6 mm. The average length from the base to the tip of Cupid's bow was 9.5, 10.0, 10.5, and 10.6 mm. The average length from the columella lateral base to the tip of Cupid's bow was 8.4, 9.9, 10.2, and 10.5 mm. The average length from the columella central base to the center of Cupid's bow was 8.3, 9.5, 9.8, and 9.9 mm. The average width of one limb of Cupid's bow was 2.7, 3.1, 3.4, and 3.5 mm. The average length from the tip of Cupid's bow to the commissure was 13.4, 14.7, 16.4, and 16.9 mm. The average intercommissural distance was 26.8, 30.3, 30.8, and 32.7 mm. The average width of the philtral column at the columella base was 3.1, 3.6, 3.7, and 4.0 mm. The average width of the philtral columns at the mid-portion was 3.7, 4.6, 4.6, and 4.6 mm. The average height of the nasal tip protrusion was 8.7, 11.0, 11.7, and 12.1 mm. The average width of the nose was 20.7, 23.7, 25.3, and 25.9 mm. In conclusion, these data are expected to be useful for patients with a bilateral cleft lip.  相似文献   
79.
目的:评估生长期不同程度矢状向和垂直向骨性不调的安氏Ⅱ类1分类错患者的疗效差异。方法:选择28例治疗后获得Ⅰ类尖牙磨牙关系的中、重度安氏Ⅱ类1分类错患者。以治疗前矢状向和垂直向不调程度分为3组。利用治疗前、后头颅侧位片分析各组治疗前、后软硬组织变化。采用SPSS12.0软件包对数据进行统计学分析。结果:3组患者治疗后ANB角均减小,第2组、第3组较第1组ANB角减小更多(P<0.01)。第3组治疗后SNA角明显减小(P<0.01),第1组(P<0.01)、第2组(P<0.05)治疗后SNB角明显增加。治疗后3组上前牙均变得直立,下前牙位置基本不变,各组间无显著差异(P>0.05)。软组织指标治疗前、后组间无显著性差异(P>0.05),但鼻唇角(P<0.05)、面凸角(P<0.05)、Z角(P<0.01)在第3组治疗前、后有显著差异。结论:对于处于生长期的不同矢状向和垂直向不调的安氏Ⅱ类1分类错患者,单纯正畸治疗结合矫形治疗,可以取得明显牙骨性及软硬组织改善。重度矢状不调伴垂直向异常的患者,能取得更显著的侧貌改变。  相似文献   
80.
A Bi2Te3 VA–VIA group compound thin film was prepared via the route of electrochemical atomic layer epitaxy in this paper. The dependence of thin film formation on the electrochemical conditions (such as deposition potential control, supporting electrolyte and substrate) was studied, and the formation process of Bi2Te3 film was determined. The results show that Bi upd on Pt occurs at more negative potential in a HNO3 supporting electrolyte than in a HClO4 supporting electrolyte, and the Te upd peak moves to a more negative potential in HClO4 supporting electrolyte solution than that in HNO3 solution; Both Te and Bi upd on an Ag substrate occur at more negative potentials than that on a Pt substrate. In order to reach steady state deposition, a potential adjustment is necessary for the first 30 or more cycles of each component. After deposition of this initial ‘buffer layer’, the potentials can be kept constant for the remaining cycles. The effect of the slope of the shift of potential used to deposit the first 30 atomic layers of Bi and Te on the deposit has also been investigated. The deposit exhibits a two phase mixture of excess elemental Bi and Bi2Te3 compound when the slope is larger than ?4 mV/p (p indicates per cycle); a single-phase Bi2Te3 compound was obtained at a slope of ?6 mV/p, and Bi4Te3 compound also appears in the deposit along with Bi2Te3 when the slope is decreased to a more negative value of ?10 mV/p.  相似文献   
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