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81.
82.
目的探讨黄芩、板蓝根、白头翁、虎杖、白花蛇舌草5种清热解毒代表药物抗流感病毒感染所致免疫炎性损伤的作用机制。方法在流感病毒亚洲甲型鼠肺适应株FM1感染小鼠后的不同时相(初期、极期、后期),采用ELISA法,动态观察清热解毒代表药物对小鼠血清肿瘤坏死因子-α(TNF-α)、白细胞介素-1(IL-1)、白细胞介素-6(IL-6)、白细胞介素-10(IL-10)、γ干扰素(IFN-γ)5种炎性细胞因子含量的影响。结果黄芩在感染后第3日可显著降低血清TNF-α、IL-1、IL-6含量,并于感染后各时相均可增加IFN-γ含量,感染后第1~5日增加IL-10含量。板蓝根在感染后第3日能显著降低血清TNF-α含量,第3~5日降低IL-6含量,并在感染后第1天升高IL-10含量,在感染后第3~5日能升高IFN-γ含量。白头翁在感染后第3日能明显降低血清TNF-α、IL-1、IL-6含量,同时显著升高IL-10含量。虎杖在感染后第1日可显著升高血清IL-10含量,在感染后第5日升高IFN-γ含量。白花蛇舌草在感染后第3日降低血清IL-6含量,在感染后第5日升高IFN-γ含量。结论黄芩的抗流感作用主要表现在流感病毒感染引起的急性外感热病的极期;板蓝根在流感病毒感染的各个时相均有一定的治疗作用;白头翁在流感病毒感染的极期可抑制炎性损伤;虎杖在感染流感病毒的初期与后期均可减少促炎性细胞因子的分泌;白花蛇舌草在流感病毒感染的极期及后期均可起到一定的抗免疫炎性损伤。各药物均具有抑制炎性损伤、防止多脏器功能衰竭、防止休克、退热和抑制促炎性细胞因子的分泌,调节机体免疫,从而减轻炎症反应的作用。  相似文献   
83.
Survivors of childhood acute lymphoblastic leukemia (ALL) treated with chemotherapy only are at risk for neurocognitive impairment. Regions of interest were identified a priori based on glucocorticoid receptor distribution, and sex‐stratified multivariable linear regression models were used to test associations between brain MRI morphology and total number of intrathecal injections, and serum concentration of dexamethasone and methotrexate. Compared with controls, ALL survivors have persistently smaller volumes in the bilateral cerebellum (P < 0.005), hippocampal subregions (P < 0.03), temporal lobe regions (P < 0.03), frontal lobe regions (P < 0.04), and parietal lobe regions (precuneus; P < 0.002). Long‐term problems with learning may be related to residual posttreatment brain differences.  相似文献   
84.
Major depressive disorder (MDD) has been the subject of many neuroimaging case–control classification studies. Although some studies report accuracies ≥80%, most have investigated relatively small samples of clinically‐ascertained, currently symptomatic cases, and did not attempt replication in larger samples. We here first aimed to replicate previously reported classification accuracies in a small, well‐phenotyped community‐based group of current MDD cases with clinical interview‐based diagnoses (from STratifying Resilience and Depression Longitudinally cohort, ‘STRADL’). We performed a set of exploratory predictive classification analyses with measures related to brain morphometry and white matter integrity. We applied three classifier types—SVM, penalised logistic regression or decision tree—either with or without optimisation, and with or without feature selection. We then determined whether similar accuracies could be replicated in a larger independent population‐based sample with self‐reported current depression (UK Biobank cohort). Additional analyses extended to lifetime MDD diagnoses—remitted MDD in STRADL, and lifetime‐experienced MDD in UK Biobank. The highest cross‐validation accuracy (75%) was achieved in the initial current MDD sample with a decision tree classifier and cortical surface area features. The most frequently selected decision tree split variables included surface areas of bilateral caudal anterior cingulate, left lingual gyrus, left superior frontal, right precentral and paracentral regions. High accuracy was not achieved in the larger samples with self‐reported current depression (53.73%), with remitted MDD (57.48%), or with lifetime‐experienced MDD (52.68–60.29%). Our results indicate that high predictive classification accuracies may not immediately translate to larger samples with broader criteria for depression, and may not be robust across different classification approaches.  相似文献   
85.
常规免疫组织化学(immunohistochemistry,IHC)是组织病理学中广泛应用的诊断技术.但该技术存在诸多局限性,包括观察者间的变异性高,每张组织切片仅能标记一个标志物.本文详细描述了各种多重检测技术,这些技术克服了上述局限性,可在单张切片上同时检测多个标志物,可对细胞组成、细胞功能和细胞间相互作用进行整合...  相似文献   
86.
BACKGROUND AND METHODS: Genotype IV hepatitis E virus (HEV) has been isolated from humans and swine. To study the relationship between the human and swine reservoirs, we estimated their respective viral burden, analyzed the genetic makeup of the virus populations, and assessed the risk of infection associated with swine farming. RESULTS: In 2 swine-farming districts of eastern China, 9.6% of swine and 0.3% of healthy human subjects excreted HEV in stool, as did 68.8% of patients with confirmed HEV infection. The virus population circulating in humans consisted of genotype I and at least 4 phylogenetically distinct subgroups of genotype IV viruses, 2 of which concurrently circulated among swine. Persons engaged in occupations related to swine farming were found to have a 74% higher risk of infection than those engaged in other occupations, and persons living in communities downstream of the swine farms were found to have a 29% higher risk of infection than persons living in communities upstream. CONCLUSIONS: Genotype IV HEV is freely transmitted between humans and swine. Because the size of the swine population and its viral burden are much larger than those of humans, transmission of the virus most likely is directed from swine to humans. Infection can be acquired through contact with swine and their waste.  相似文献   
87.
88.
Snakebites in children and teenagers are relatively uncommon in the metropolitan city of Hong Kong. They are rarely fatal but may cause significant morbidity and fear. We report two cases of snakebites to illustrate that the spectrum of morbidity is independent of the size of the snakes. A 7-year-old boy was bitten in successions by a green snake. Envenomation occurred at the second bite site. He developed local and systemic signs that were promptly relieved with anti-venom therapy at the intensive care unit. An 18-year-old girl was bitten by a large python but only sustained minor local soft tissue injuries. This report serves to alert the public that snake may bite in successions and envenomation may occur with the subsequent bite.
Conclusion:  A small snake may be venomous and a large snake may not be. Avoidable risk factors associated with snakebites (such as avoiding areas known to harbour snakes in the evening in summer and autumn and wearing protective footwear) are highlighted.  相似文献   
89.
Background Recently, mutations in the filaggrin gene (FLG) have been shown to be a major predisposing factor for atopic dermatitis (AD). Objective In this study, we evaluated the influence of four prevalent mutations (R501X, 2282del4, R2447X and S3247X) in a large cohort of 462 Austrian and German AD patients and in 402 control individuals. Results We found a strong association of the FLG mutations with AD. Subgroup analysis revealed a significantly higher proportion of patients with an early age of disease onset and significantly higher median serum IgE levels among mutation carriers. Furthermore, we observed an overrepresentation of null alleles in AD patients with concomitant asthma compared with those without this co‐morbidity. Conclusion Our data confirm and extend the knowledge of the influence of FLG mutations in AD.  相似文献   
90.
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