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991.
人类体细胞突变的发生和积累,又称体细胞嵌合现象。其中,嵌合染色体变异(mCA)对基因组完整性的影响最为显著,被视为人类衰老的表型之一。随着全球人口老龄化进程的加速,了解mCA的人群流行病学分布及其影响因素,有助于探索人体衰老进程中“基因组失稳”及其相关生物学机制,为人类年龄相关疾病的一级预防提供科学依据。本文旨在汇总既往大规模人群研究结果,对外周血常染色体mCA的人群流行病学分布及其影响因素进行综述。 相似文献
992.
目的 分析广州市外籍人员的社会支持、网络社交、性行为特征及相关因素,为有效开展外籍人员干预活动提供参考依据。方法 采用横断面调查研究设计,在2019年11月至2020年1月,对符合标准的研究对象采用线下和线上相结合的方式开展调查,收集人口学特征、社会支持、网络社交行为、性行为等信息。采用统计学方法对可能影响临时性行为的因素进行分析。结果 纳入研究的434名外籍人员中,线下调查241人,线上调查193人。男性占68.4%(297/434);年龄(31.0±8.8)岁;来源地为非洲地区的占79.0%(343/434);经商占46.5%(202/434),学生占48.2%(209/434);在中国有生意伙伴、家人陪伴的比例分别为59.4%(258/434)和28.1%(122/434);在中国有关系密切的朋友<10人的比例为57.1%(248/434);每日使用社交软件时间为1~3 h的占43.3%(188/434);最近3个月发生临时性行为占15.2%(55/363)。Logistic多元回归分析结果显示,与每日使用社交软件时间<1 h者相比,>6 h者更有可能最近3个月发生临时性行为(OR=3.63,95%CI:1.31~10.08)。结论 广州市外籍人员中每日使用社交软件时间较长者更有可能发生临时性行为。合理运用社交软件进行艾滋病宣传教育可促进外籍人员的健康意识。 相似文献
993.
孤独症谱系障碍(ASD)的核心诊断特征是社会交流障碍以及受限和重复的行为和兴趣,症状常在生命的最初几年出现。过去的二十年内,神经成像揭示了许多“社会性”大脑的非典型活动和异常连通性的发现,包括梭状回对面部和凝视的分析、杏仁核的情绪处理、默认模式网络的心智化以及镜像神经元相关区域对他人行为的模仿和理解,但对于社交功能缺陷潜在的神经生理机制还未达成一致。除了方法学上的挑战以及聚焦于单个大脑网络的连通性研究以外,更深层次的问题是ASD的极强异质性。这种不一致的发现,可能是由于诊断标准的变化以及学龄前期的ASD患儿存在非典型的神经发育轨迹,因此,有必要进行孤独症亚型的队列研究和大样本的纵向队列研究。 相似文献
994.
目的 评价润燥止痒胶囊联合枸地氯雷他定治疗慢性荨麻疹(CU)安全性和有效性。方法 计算机检索Embase、Cochrane图书馆、PubMed、中国知网、万方数据库,纳入评价润燥止痒胶囊联合枸地氯雷他定治疗CU的随机对照试验,检索时间从建库到2021年6月。由两名作者提取资料、选取文献、并评价纳入文章的偏倚风险后,采用RevMan5.4软件进行meta分析。结果 共纳入7项随机对照试验,包括611例CU患者,其中研究组307例,对照组304例。meta分析结果显示,研究组总有效率(OR=6.72,95%CI:3.62~12.46)、痊愈率(OR=1.93,95%CI:1.35~2.75)和降低免疫球蛋白E水平(MD=-34.54,95%CI:-39.12~-29.95)优于对照组,不良反应发生率(OR=0.36,95%CI:0.14~0.93,P<0.05)低于对照组,差异有统计学意义(P<0.05)。结论 润燥止痒胶囊联合枸地氯雷他定治疗CU安全、有效。 相似文献
995.
996.
Minji Kang Ryeon Heo Seojin Park Seo-Yeong Mun Minju Park Eun-Taek Han Jin-Hee Han Wanjoo Chun Kwon-Soo Ha Hongzoo Park Won-Kyo Jung Il-Whan Choi Won Sun Park 《The Korean journal of physiology & pharmacology》2022,26(4):277
To investigate the adverse effects of clozapine on cardiovascular ion channels, we examined the inhibitory effect of clozapine on voltage-dependent K+ (Kv) channels in rabbit coronary arterial smooth muscle cells. Clozapine-induced inhibition of Kv channels occurred in a concentration-dependent manner with an half-inhibitory concentration value of 7.84 ± 4.86 µM and a Hill coefficient of 0.47 ± 0.06. Clozapine did not shift the steady-state activation or inactivation curves, suggesting that it inhibited Kv channels regardless of gating properties. Application of train pulses (1 and 2 Hz) progressively augmented the clozapine-induced inhibition of Kv channels in the presence of the drug. Furthermore, the recovery time constant from inactivation was increased in the presence of clozapine, suggesting that clozapine-induced inhibition of Kv channels is use (state)-dependent. Pretreatment of a Kv1.5 subtype inhibitor decreased the Kv current amplitudes, but additional application of clozapine did not further inhibit the Kv current. Pretreatment with Kv2.1 or Kv7 subtype inhibitors partially blocked the inhibitory effect of clozapine. Based on these results, we conclude that clozapine inhibits arterial Kv channels in a concentration- and use (state)-dependent manner. Kv1.5 is the major subtype involved in clozapine-induced inhibition of Kv channels, and Kv2.1 and Kv7 subtypes are partially involved. 相似文献
997.
Dongdong Lu Yu Pi Hao Ye Yujun Wu Yu Bai Shuai Lian Dandan Han Dongjiao Ni Xinhua Zou Jinbiao Zhao Shuai Zhang Bas Kemp Nicoline Soede Junjun Wang 《Nutrients》2022,14(12)
Constipation is a common problem in sows and women during late pregnancy. Dietary fiber has potential in the regulation of intestinal microbiota, thereby promoting intestinal motility and reducing constipation. However, the effects of fibers with different physicochemical properties on intestinal microbe and constipation during late pregnancy have not been fully explored. In this study, a total of 80 sows were randomly allocated to control and one of three dietary fiber treatments from day 85 of gestation to delivery: LIG (lignocellulose), PRS (resistant starch), and KON (konjaku flour). Results showed that the defecation frequency and fecal consistency scores were highest in PRS. PRS and KON significantly increased the level of gut motility regulatory factors, 5-hydroxytryptamine (5-HT), motilin (MTL), and acetylcholinesterase (AChE) in serum. Moreover, PRS and KON promoted the IL-10 level and reduced the TNF-α level in serum. Furthermore, maternal PRS and KON supplementation significantly reduced the number of stillborn piglets. Microbial sequencing analysis showed that PRS and KON increased short-chain fatty acids (SCFAs)-producing genera Bacteroides and Parabacteroides and decreased the abundance of endotoxin-producing bacteria Desulfovibrio and Oscillibacter in feces. Moreover, the relative abundance of Turicibacter and the fecal butyrate concentration in PRS were the highest. Correlation analysis further revealed that the defecation frequency and serum 5-HT were positively correlated with Turicibacter and butyrate. In conclusion, PRS is the best fiber source for promoting gut motility, which was associated with increased levels of 5-HT under specific bacteria Turicibacter and butyrate stimulation, thereby relieving constipation. Our findings provide a reference for dietary fiber selection to improve intestinal motility in late pregnant mothers. 相似文献
998.
Yong Zhuo Pu Yang Lun Hua Lei Zhu Xin Zhu Xinfa Han Xiaoxue Pang Shengyu Xu Xuemei Jiang Yan Lin Lianqiang Che Zhengfeng Fang Bin Feng Jianping Wang Jian Li De Wu Jiankui Huang Chao Jin 《Toxins》2022,14(6)
Background: We investigated the effect of replacing normal corn (NC) or normal wheat bran (NW) with moldy corn (MC) or moldy wheat bran (MW) on growth, ovarian follicular reserves, and oxidative status. Methods: Sixty-three Landrace × Yorkshire gilts were assigned to seven diets formulated by using MC to replace 0% (control), 25% (25% MC), 50% (50% MC), 75% (75% MC), and 100% NC (100% MC), MW to replace 100% NW (100% MW), and MC and MW to replace 100% NC and 100% NW (100% MC + MW), from postnatal day 110 to day 19 of the second estrous cycle. Results: Feeding the gilts with MC or MW induced a lower average daily gain at days 29–56 of the experiment. Age at puberty remained unchanged, but MC inclusion resulted in a linear decrease in antral follicles with diameter >3.0 mm, and control gilts had a 12.7 more large antral follicles than gilts in the 100% MC + MW treatment. MC inclusion linearly decreased the numbers of primordial follicles, growing follicles, and corpora lutea, associated with a lower anti-Müllerian hormone level in serum and 17β-estradiol level in follicular fluid. MC inclusion decreased the serum concentrations of insulin-like growth factor 1 and its mRNA levels in the liver, combined with higher malondialdehyde concentration and lower total superoxide dismutase activities in serum and liver. Conclusion: Chronic exposure to MC-containing diets caused the loss of follicles, even if levels of deoxynivalenol, zearalenone, and aflatoxin B1 were below the levels allowed by China and Europe standards. 相似文献
999.
1000.
Choeum Kang Haesung Yoon Sowon Park Jisoo Kim Kyunghwa Han Seung Kim Hong Koh Mi-Jung Lee Hyun Joo Shin 《Yonsei medical journal》2022,63(7):675
PurposeTo identify initial abdominal computed tomography (CT) and laboratory findings prior to a diagnosis of Crohn’s disease (CD) in children.Materials and MethodsIn this retrospective study, patients (≤18 year-old) who were diagnosed with CD from 2004 to 2019 and had abdominal CT just prior to being diagnosed with CD were included in the CD group. Patients (≤18 years old) who were diagnosed with infectious enterocolitis from 2018 to 2019 and had undergone CT prior to being diagnosed with enterocolitis were included as a control group. We assessed the diagnostic performances of initial CT and laboratory findings for the diagnosis of CD using logistic regression and the area under the curve (AUC).ResultsIn total, 107 patients (50 CD patients, 57 control patients) were included, without an age difference between groups (median 13 years old vs. 11 years old, p=0.119). On univariate logistic regression analysis, multisegmental bowel involvement, mesenteric vessel engorgement, higher portal vein/aorta diameter ratio, longer liver longitudinal diameter, lower hemoglobin (≤12.5 g/dL), lower albumin (≤4 g/dL), and higher platelet (>320×103/µL) levels were significant factors for CD. On multivariate analysis, multisegmental bowel involvement [odds ratio (OR) 111.6, 95% confidence interval (CI) 4.778–2605.925] and lower albumin levels (OR 0.9, 95% CI 0.891–0.993) were significant factors. When these two features were combined, the AUC value was 0.985 with a sensitivity of 96% and specificity of 100% for differentiating CD.ConclusionMultisegmental bowel involvement on CT and decreased albumin levels can help differentiate CD from infectious enterocolitis in children prior to a definite diagnosis of CD. 相似文献