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31.
目的探讨引起花斑癣不同临床色素表现的马拉色菌与角质形成细胞共培养,导致与黑素合成相关的细胞因子的变化。方法MTT法筛选不同比例的马拉色菌对角质形成细胞增殖率的影响;用色沉和色减区分离的马拉色菌与角质形成细胞共培养,在不同时间段收集上清液,ELISA法测定碱性成纤维细胞因子(b-FGF)、内皮素-1(ET-1)、神经生长因子-β(NGF-β)、白介素-1α(IL-1α)、白介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)和干细胞因子(SCF)的动态变化。结果角质形成细胞与马拉色菌在1∶10比例以下,角质形成细胞的生长状况不受马拉色菌的影响(P〉0.05)。当比例提高至1∶20以上时,角质形成细胞的生长受到显著抑制(P〈0.01)。马拉色菌刺激角质形成细胞分泌IL-1α、IL-6、TNF-α、ET-1增加(P〈0.01)。未检测到b-FGF、NGF-β和SCF的产生(P〉0.05)。色沉区马拉色菌刺激产生的ET-1显著高于色减区(P〈0.01)。结论马拉色菌刺激角质形成细胞分泌黑素合成相关因子的能力不同。ET-1在花斑癣色素沉着中可能起了一定作用。  相似文献   
32.
ObjectiveTo explore the association between lipid profiles and left ventricular hypertrophy in a Chinese general population.MethodsWe conducted a retrospective observational study to investigate the relationship between lipid markers [including triglycerides, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein (HDL) cholesterol, non-HDL-cholesterol, apolipoprotein A-I, apolipoprotein B, lipoprotein[a], and composite lipid profiles] and left ventricular hypertrophy. A total of 309,400 participants of two populations (one from Beijing and another from nationwide) who underwent physical examinations at different health management centers between 2009 and 2018 in China were included in the cross-sectional study. 7,475 participants who had multiple physical examinations and initially did not have left ventricular hypertrophy constituted a longitudinal cohort to analyze the association between lipid markers and the new-onset of left ventricular hypertrophy. Left ventricular hypertrophy was measured by echocardiography and defined as an end-diastolic thickness of the interventricular septum or left ventricle posterior wall > 11 mm. The Logistic regression model was used in the cross-sectional study. Cox model and Cox model with restricted cubic splines were used in the longitudinal cohort.ResultsIn the cross-sectional study, for participants in the highest tertile of each lipid marker compared to the respective lowest, triglycerides [odds ratio (OR): 1.250, 95%CI: 1.060 to 1.474], HDL-cholesterol (OR: 0.780, 95%CI: 0.662 to 0.918), and lipoprotein(a) (OR: 1.311, 95%CI: 1.115 to 1.541) had an association with left ventricular hypertrophy. In the longitudinal cohort, for participants in the highest tertile of each lipid marker at the baseline compared to the respective lowest, triglycerides [hazard ratio (HR): 3.277, 95%CI: 1.720 to 6.244], HDL-cholesterol (HR: 0.516, 95%CI: 0.283 to 0.940), non-HDL-cholesterol (HR: 2.309, 95%CI: 1.296 to 4.112), apolipoprotein B (HR: 2.244, 95%CI: 1.251 to 4.032) showed an association with new-onset left ventricular hypertrophy. In the Cox model with forward stepwise selection, triglycerides were the only lipid markers entered into the final model.ConclusionLipids levels, especially triglycerides, are associated with left ventricular hypertrophy. Controlling triglycerides level potentiate to be a strategy in harnessing cardiac remodeling but deserve to be further investigated.  相似文献   
33.
目的 评价高压氧治疗对阿尔茨海默病(alzheimer's disease,AD)大鼠海马内神经元凋亡及p38丝裂原蛋白激酶(p38 mitogenactivated protein kinases,p38MAPK)表达的影响. 方法 18只雄性SD大鼠,体重260 g~290 g,采用随机数字表法分为3组(每组6只):生理盐水组(NS组),海马区注射生理盐水;阿尔茨海默病组(AD组),海马区注射Aβ1-40;高压氧组(HBO组),海马区注射Aβ1-40,并于术后1 d~7d行每天1次的高压氧治疗.应用脑立体定位仪于大鼠海马区注射Aβ1-40制备AD模型.于术前1d和术后1、7、14、21 d行水迷宫行为学测试.于术后21 d水迷宫行为学测试结束后处死大鼠,采用苏木精-伊红染色(hematoxylin-eosin,HE)方法染色海马组织病理结构,TUNEL法标记检测凋亡细胞,免疫印迹法(Western bolt)法测定海马内p38MAPK蛋白磷酸化水平. 结果 术后21 d时,与NS组比较,AD组大鼠上台前路程和逃避潜伏期增加[(379±41)、(1 978±120) cm,(16.0±2.8)、(78.4±10.8)s](P<0.05);与AD组比较,HBO组大鼠上台前路程和逃避潜伏期减少[(1978±120)、(1 246±96) cm,(78.4±10.8)、(51.7±6.2)s](P<0.05).与NS组比较,AD组和HBO组大鼠海马组织细胞凋亡率[(6.3±13)%,(45.2±5.1)%]及p38MAPK蛋白磷酸化表达升高(0.16±0.06),(0.54±0.10)(P<0.05);与AD组比较,HBO组海马组织细胞凋亡率[(45.2±5.1)%,(22.5±3.7)%]及p38 MAPK蛋白磷酸化表达下降[(0.54±0.10),(0.31±0.08)](P<0.05).结论 高压氧治疗可有效缓解AD大鼠认知功能障碍,且能够抑制海马内神经元凋亡,其机制与降低p38MAPK的磷酸化水平有关.  相似文献   
34.

OBJECTIVE

Gut microbiome dysbiosis is associated with numerous diseases, including type 1 diabetes. This pilot study determines how geographical location affects the microbiome of infants at high risk for type 1 diabetes in a population of homogenous HLA class II genotypes.

RESEARCH DESIGN AND METHODS

High-throughput 16S rRNA sequencing was performed on stool samples collected from 90 high-risk, nonautoimmune infants participating in The Environmental Determinants of Diabetes in the Young (TEDDY) study in the U.S., Germany, Sweden, and Finland.

RESULTS

Study site–specific patterns of gut colonization share characteristics across continents. Finland and Colorado have a significantly lower bacterial diversity, while Sweden and Washington state are dominated by Bifidobacterium in early life. Bacterial community diversity over time is significantly different by geographical location.

CONCLUSIONS

The microbiome of high-risk infants is associated with geographical location. Future studies aiming to identify the microbiome disease phenotype need to carefully consider the geographical origin of subjects.  相似文献   
35.
AIM: To evaluate the peripheral arterial filling time (PAFT) and venous filling time (VFT) in eyes without known diseases that may influence filling process using ultra-widefield (UWF) fluorescein angiography (FA), and to review the peripheral retina fluorescence features. METHODS: A total of 30 eyes of 30 patients were retrospectively reviewed in this observational study. UWF-FA was performed using Optos 200Tx. PAFT and VFT was recorded. The interval between the arterial or venous filling completion and the previous photo was documented. The appearance of the far peripheral retina was described as either granular background fluorescence or mottled fluorescent band or vascular leakage. Terminal vascular patterns was described as loop pattern or branching pattern. Microvascular abnormalities such as arteriovenous shunting, vessels crossing the horizontal raphe, right angle vessels, terminal networks, capillary nonperfusion, drusen or microaneurysms were evaluated. RESULTS: The normal limits of PAFT was 3.397-8.984s and 4.399-11.753s for VFT. The appearance of the far peripheral retina, defined as granular background (63%), mottled fluorescence (20%), or vascular leakage (17%), was symmetrical between both eyes. Capillary nonperfusion (23%) and microaneurysms (40%) were more frequently found in eyes with loop pattern than in eyes with branching pattern. Other peripheral signs such as right angle vessels (73%), and terminal networks (80%) were commonly seen on UWF-FA in the normal peripheral retina. CONCLUSION: The main courses of retinal artery and vein filling time are overlapping with each other on UWF-FA. Notably, the arterial filling process is completed in the arteriovenous phase rather than the traditionally named arterial phase. There are various manifestations in the peripheral retina of normal eyes.  相似文献   
36.
Diffusion and sorption of five gases (H2, N2, O2, CO2, CH4) in hydrogenated nitrile butadiene rubber (HNBR) and ethylene–propylene–diene rubber (EPDM) have been investigated by molecular dynamics (MD) and grand canonical Monte Carlo (GCMC) simulations. The diffusion coefficients of gas molecules in HNBR and EPDM are well correlated with the effective penetrant diameter except for CO2. CO2 shows a lower diffusion coefficient due to its linear shape. Additionally, the favorable interaction between CO2 and HNBR is another factor for its lower diffusion coefficient in HNBR. HNBR shows lower diffusion coefficients than EPDM. This is because the polar –CN groups in HNBR chains increase interchain cohesion and result in tight intermolecular packing, low free volume and poor chain mobility, which decreases the diffusion coefficients of HNBR. The solubility coefficients of CH4, O2, N2 and H2 in HNBR are lower than those in EPDM, which is a result of the weak HNBR–penetrant interactions and low free volume of HNBR. However, the solubility coefficient of CO2 in HNBR is higher than in EPDM. This is attributed to the strong interaction between CO2 and HNBR. H2, O2, N2 and CH4 show lower permeability coefficients in HNBR than in EPDM, while CO2 has higher permeability coefficients in HNBR. These molecular details provide critical information for the understanding of structures and gas transport between HNBR and EPDM.

Diffusion and sorption of five gases (H2, N2, O2, CO2, CH4) in HNBR and EPDM were explored by MD and GCMC simulations.  相似文献   
37.
Chen WH  Wang M  Yu SS  Su L  Zhu DM  She JQ  Cao XJ  Ruan DY 《Neuroscience》2007,147(3):853-864
Lead (Pb(2+)) exposure in development induces impairments of synaptic plasticity in the hippocampal dentate gyrus (DG) area of the anesthetized rats in vivo. The common chelating agents have many adverse effects and are incapable of alleviating lead-induced neurotoxicity. Recently, CQ, clioquinol (5-chloro-7-iodo-8-hydroxy-quinoline), which is a transition metal ion chelator and/or ionophore with low affinity for metal ions, has yielded some promising results in animal models and clinical trials related to dysfunctions of metal ions. In addition, CQ-associated side effects are believed to be overcome with vitamin B12 (VB12) supplementation. To determine whether CQ treatment could rescue impairments of synaptic plasticity induced by chronic Pb(2+) exposure, we investigated the input/output functions (I/Os), paired-pulse reactions (PPRs) and long-term potentiation (LTP) of different treatment groups in hippocampal DG area of the anesthetized rat in vivo by recording field potentials and measured hippocampal Pb(2+) concentrations of different treatment groups by PlasmaQuad 3 inductive coupled plasma mass spectroscopy. The results show: CQ alone does not rescue the lead-induced impairments of synaptic plasticity in hippocampal DG area of the anesthetized rats in vivo; VB12 alone partly rescues the lead-induced impairments of LTP; however the co-administration of CQ and VB12 totally rescues these impairments of synaptic plasticity and moreover, the effects of CQ and VB12 co-administration are specific to the lead-exposed animals.  相似文献   
38.
Clinicians use molecular tests to detect Herpesviridae from blood without fully appreciating limitations of testing. Studies are needed to enhance our understanding of the impact of Herpesviridae latency on molecular testing. We retrospectively performed quantitative Epstein-Barr virus (EBV) on sera from patients between the ages of 1 and 30 who demonstrated serologic evidence of acute EBV (n = 50) or remote EBV (n = 50) infection. Epstein-Barr virus DNA was detected in 70% of acutely infected and 4% of remotely infected patients. Sera from acutely infected patients had higher EBV copy number than convalescent sera. Our results suggest that serology should be performed as the initial diagnostic test for acute EBV. The role for polymerase chain reaction in immunocompromised patients with impaired antibody responses or as a 2nd-line diagnostic test when serologic results are equivocal deserves further study.  相似文献   
39.
目的研究床上体操配合音疗对脑卒中早期患者偏瘫肢体功能的影响.方法将100例脑卒中偏瘫患者分为2组,常规组(n=50),常规+训练组(n=50).常规组给予常规内科治疗护理.常规+训练组除常规内科治疗护理外,根据患者肢体运动功能情况选择适合不同时期的床上体操和音疗训练,治疗前后予Brunnstrom法运动功能评估,日常生活活动能力Barthel指数评估,心理评估.结果治疗前2组日常生活活动能力、肢体运动功能、心理评估无差异,治疗后1个月常规+训练组日常生活活动能力(Barthel指数)、运动功能(Brunnstrom法)明显高于常规组(P<0.05).常规+训练组的恐怖、抑郁、强迫、焦虑症状得到明显改善(P<0.05).常规组治疗护理组抑郁、强迫、焦虑症状无明显改善(P>0.05),仅恐怖症状有改善(P<0.05).结论音乐床上体操对脑卒中早期偏瘫肢体功能恢复和心理障碍治疗有明显作用,有利于提高患者的生活质量.  相似文献   
40.
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