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101.
目的:观察含0.02%吡格列酮的饲料对NOD鼠糖尿病发病率的影响,分析巨噬细胞在吡格列酮预防NOD鼠糖尿病中的作用。方法:实验于2003-01/2005-01在中南大学湘雅二医院动物实验室及中心实验室完成。4周龄NOD雌鼠56只,随机数字表法分为吡格列酮组(n=25)和对照组(n=26),分别摄食含0.02%吡格列酮的混合饲料和普通营养饲料。自10周龄开始,每周测尿糖1次,尿糖阳性后用血糖仪测血糖,连续两次血糖≥16.7mmol/L即诊断为糖尿病。两组各取12周龄NOD雌鼠15只,处死前4d腹腔注射30g/L的硫代乙醇酸钠2mL,麻醉后摘除眼球法处死小鼠后腹腔灌洗收集巨噬细胞,加入脂多糖共同培养24d后收集上清,ELISA法测细胞因子肿瘤坏死因子α、白细胞介素6水平。结果:小鼠56只全部进入糖尿病发病率分析;进入腹腔巨噬细胞肿瘤坏死因子α、白细胞介素6的水平结果分析20只。①30周龄时,对照组25只小鼠有20只发生了糖尿病,发病率80.0%,平均发病时间为(139.2±38.2)d;吡格列酮组26只中有14只发生了糖尿病,发病率为53.8%,平均发病时间为(153.0±28.1)d,与对照组相比,吡格列酮组发病率明显降低(P<0.05)。②12周龄时对照组NOD鼠腹腔巨噬细胞肿瘤坏死因子α、白细胞介素6水平与吡格列酮组差异无显著性意义[(537.4±112.49),(448.9±92.18)ng/L;(551.2±108.23),(461.7±80.49)ng/L,P>0.05]。结论:吡格列酮在一定程度上预防和延缓NOD鼠糖尿病的发生;吡格列酮对NOD鼠糖尿病和胰岛炎的预防作用可能与巨噬细胞无明显关系。  相似文献   
102.
BACKGROUND: Platelets become activated during storage, which results in secretion of granules, vesiculation of microparticles, secretion of protein, and a number of other biochemical and morphologic processes that decrease the utility of platelet concentrates stored for transfusion. STUDY DESIGN AND METHODS: To evaluate the quality of stored platelet concentrates, the cell surface expression of specific activation-dependent antigens (CD62 and lysosome-associated membrane proteins 1 and 2 [LAMP-1, LAMP-2]) on platelets stored in a hospital blood bank over a 7-day period was examined. Relative microparticle counts and the expression of CD62 by microparticles, as well as platelet concentrate supernatant levels of soluble CD62, were determined. RESULTS: The percentage of platelets expressing CD62 increased significantly from Day 1 to Day 5 (p < 0.05) of storage; the mean fluorescence values for CD62 did not. In contrast, the mean fluorescence values of LAMP-1 and LAMP-2 rose significantly (p < 0.01 and p < 0.05, respectively) between Days 1 and 5. Significant declines in CD62, LAMP-1, and LAMP-2 percent expression and mean fluorescence were seen on Day 6 of storage (p < 0.001). Microparticle numbers increased significantly during storage and correlated with levels of CD62 protein (free and membrane-bound) (r = 0.95 vs. Day 2, p < 0.05; r = 0.88 vs. Day 5, p < 0.05). CONCLUSION: Flow cytometric evaluations of the expression of cell surface CD62, LAMP-1, and LAMP-2 are complementary tests that, especially when used in conjunction with the quantitation of CD62 protein, provided a simple and effective means of evaluating the quality of platelet concentrates stored for transfusion.  相似文献   
103.
Early interactions between lung dendritic cells (LDCs) and Mycobacterium tuberculosis, the etiological agent of tuberculosis, are thought to be critical for mounting a protective anti-mycobacterial immune response and for determining the outcome of infection. However, these interactions are poorly understood, at least at the molecular level. Here we show that M. tuberculosis enters human monocyte-derived DCs after binding to the recently identified lectin DC-specific intercellular adhesion molecule-3 grabbing nonintegrin (DC-SIGN). By contrast, complement receptor (CR)3 and mannose receptor (MR), which are the main M. tuberculosis receptors on macrophages (Mphis), appeared to play a minor role, if any, in mycobacterial binding to DCs. The mycobacteria-specific lipoglycan lipoarabinomannan (LAM) was identified as a key ligand of DC-SIGN. Freshly isolated human LDCs were found to express DC-SIGN, and M. tuberculosis-derived material was detected in CD14(-)HLA-DR(+)DC-SIGN(+) cells in lymph nodes (LNs) from patients with tuberculosis. Thus, as for human immunodeficiency virus (HIV), which is captured by the same receptor, DC-SIGN-mediated entry of M. tuberculosis in DCs in vivo is likely to influence bacterial persistence and host immunity.  相似文献   
104.

Background

Flap surgery for deep pelvic pressure ulcers (PPUs) has been found effective, but the recurrence rate remains high and few risk factors have been identified.

Objective

We evaluated risk factors for PU recurrence after primary flap surgery in people with spinal cord injury (SCI).

Patients and methods

This observational retrospective study based on medical charts included all individuals with SCI who underwent primary flap surgery for a PPU in the Hérault department in France between 2006 and 2014. Overall, 100 biomedical, psychological, socioeconomic and care management factors were studied. The primary outcome was PPU recurrence (surgical site and/or other pelvic site). The secondary outcome was recurrence at the surgical site. Cox proportional hazards regression was used to determine associated factors, estimating hazard ratios (HRs) and 95% confidence intervals (CIs).

Results

We included 85 patients. Half had a PPU recurrence, and in one-third, the recurrence was at the surgical site. On multivariate analysis, global PPU recurrence was associated with colostomy (HR = 2.79) and living with a partner (HR = 2.29). Non-traumatic SCI and sacral wound were associated with PPU recurrence (HR = 3.39, HR = 0.48) and recurrence at the surgical site (HR = 3.3, HR = 0.3).

Conclusion

Risk factors of PPU recurrence are based on both biomedical and social models. After primary flap surgery, the risk of recurrence justifies regular follow-up and strict monitoring.  相似文献   
105.
The butterfly lizard (Leiolepis reevesii rubritaeniata) has the diploid chromosome number of 2n = 36, comprising two distinctive components, macrochromosomes and microchromosomes. To clarify the conserved linkage homology between lizard and snake chromosomes and to delineate the process of karyotypic evolution in Squamata, we constructed a cytogenetic map of L. reevesii rubritaeniata with 54 functional genes and compared it with that of the Japanese four-striped rat snake (E. quadrivirgata, 2n = 36). Six pairs of the lizard macrochromosomes were homologous to eight pairs of the snake macrochromosomes. The lizard chromosomes 1, 2, 4, and 6 corresponded to the snake chromosomes 1, 2, 3, and Z, respectively. LRE3p and LRE3q showed the homology with EQU5 and EQU4, respectively, and LRE5p and LRE5q corresponded to EQU7 and EQU6, respectively. These results suggest that the genetic linkages have been highly conserved between the two species and that their karyotypic difference might be caused by the telomere-to-telomere fusion events followed by inactivation of one of two centromeres on the derived dicentric chromosomes in the lineage of L. reevesii rubritaeniata or the centric fission events of the bi-armed macrochromosomes and subsequent centromere repositioning in the lineage of E. quadrivirgata. The homology with L. reevesii rubritaeniata microchromosomes were also identified in the distal regions of EQU1p and 1q, indicating the occurrence of telomere-to-telomere fusions of microchromosomes to the p and q arms of EQU1.  相似文献   
106.
Youths, aged 15–24 years, comprise a large fragment of the total population in Thailand, and unsafe sexual behaviours are increasing, nowadays, among young people. The study was conducted to explore the characteristics of youths and other conducive, facilitating and reinforcing factors associated with risk perception of sexually transmitted infections (STIs) among the study population. Data employed in this study were derived from the site of the Kanchanaburi Demographic Surveillance System of Thailand 2004 using a stratified systemic design. The study population was mainly young current condom-users aged 15–24 years, and cross-sectional analysis was done on this populace. The findings revealed that youths who fell into the single (unmarried) category having temporary partners were more likely to perceive the risks associated with STIs in relation to using condom. A greater proportion of unmarried youths was engaged in sexual activity before the age of 20 years and that condom-use was also inconsistent. Youths having temporary partners were more likely to perceive risk and reason for using a condom than when with their regular partner. Education played a significant role in risk perception of STIs. Risk perception was increasing with the increasing level of education. Other conducive and facilitating factors, such as household wealth, living in urban or semi-urban areas, and access to mass media such as television, also had a positive influence on risk perception. The odds ratio showed that condom-users who had indulgence in liquor were less likely to perceive the risk of STIs. Overall, socioeconomic status had a great influence on risk perception of STIs. Finally, youths exhibiting high-risk sexual behaviour need realistic risk assessments and positive ways of incorporating condom into their sexual lives.Key words: Condom-use, Education, Risk perception, Sexual partners, Youths, Thailand  相似文献   
107.
Ecotoxicology - To characterize environmental risks linked to former uranium mines in the Limousin region of France, a study was conducted on fish health effects from uranium releases. Two private...  相似文献   
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