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21.
Detection of DNA from infectious laryngotracheitis virus by colourimetric analyses of polymerase chain reactions 总被引:3,自引:0,他引:3
A combination of the polymerase chain reaction and a novel ELISA-type DNA colourimetric assay (developed from studies with a retrovirus from man) was used in a preliminary study to detect DNA from avian infectious laryngotracheitis virus. The method is sensitive, specific and easy to perform. Since it can be readily adapted for the detection of DNA from other sources it could be useful for the identification of a variety of pathogens from other species of veterinary importance. 相似文献
22.
Albert Z. Kapikian Anthony R. Kalica J.Wai-Kuo Shih W.Lee Cline Thomas S. Thornhill Richard G. Wyatt Robert M. Chanock Hyun Wha Kim John L. Gerin 《Virology》1976,70(2):564-569
The buoyant density in cesium chloride of the human reoviruslike (HRVL) agent of infantile gastroenteritis was studied utilizing electron microscopy and complement fixation (CF) for the detection of reoviruslike particles in fractions of the density gradient. Three virus positive stool filtrates were studied. “Full” reoviruslike particles had a density of 1.35–1.37 g/cm3, whereas “empty” particles had a density of 1.29 g/cm3. Peak CF activity coincided with the peak fraction of both the “full” and “empty” reoviruslike particles. In addition, by differential centrifugation, CF activity was also associated with the virion and not a “soluble” antigen. 相似文献
23.
Michael Kaliner 《The Journal of allergy and clinical immunology》1976,58(2):308-315
The cholinergically innervated human eccrine sweat gland is a readily available organ permitting the assessment in allergic patients of cholinergic reactivity with few or no adrenergic influences. The sweat responses of four matched groups (male allergic, female allergic, male control, and female control) to intradermal Mecholyl from 0.1 μg to 100 μg was compared; the 45 male and 45 female allergic patients demonstrated statistically significant increases in sweat responses to essentially all concentrations of Mecholyl examined. No difference in the sweat responses of patients with allergic rhinitis alone as compared with patients with both allergic rhinitis and allergic asthma was noted. Five patients with intrinsic asthma most closely resembled the allergic groups in their responses and 8 patients with vasomotor rhinitis sweated at or below the control groups. The increased sensitivity of allergic patients to cholinergic stimulation as measured by eccrine sweat responses suggests that this hyperresponsiveness may be one of the underlying defects in allergic disease. 相似文献
24.
25.
目的分析124例巴尔病毒(EBV)感染患儿的临床特征和血清免疫因子水平。方法选择2016年12月-2019年12月于海南医学院第一附属医院确诊的124例EBV感染患儿为研究组,根据临床表现分为传染性单核细胞增多症(IM)组43例和单纯性EBV组81例,选择同期健康体检儿童62名为对照组。记录所有患儿入组时的年龄、性别、临床症状;荧光定量PCR反应检测外周血淋巴细胞中EBV DNA载量;检测血清白细胞介素-6(IL-6)、IL-2和肿瘤坏死因子-α(TNF-α)水平,流式细胞仪分析外周血T淋巴细胞水平;Pearson相关性分析外周血T淋巴细胞亚群与EBV DNA载量之间的相关性。结果 IM组患儿的年龄为(5.13±1.56)岁,大于单纯性EBV组(P<0.05),出现发热、咽峡炎、淋巴结肿大、脾肿大、肝肿大、眼睑水肿、鼻塞、打鼾的比例为88.37%、93.02%、93.02%、48.84%、60.47%、32.56%、55.81%和46.51%,高于单纯性EBV组(P<0.05);IM组患儿的血CD3+T、CD8+T细胞、IL-6、TNF-α为分别为(73.25±7.16)%、(40.19±4.21)%、(33.68±5.71)ng/L、(72.52±11.26)ng/L高于对照组,而CD4+T、CD4+/CD8+T细胞、IL-2分别为(34.86±3.75)%、(0.89±0.15)、(10.43±3.38)ng/L则均低于对照组(P<0.05);外周血CD3+T和CD8+T细胞水平均与病毒载量呈正相关(r=0.314,0.447,P<0.05),CD4+T和CD4+/CD8+T细胞水平与病毒载量呈负相关(r=-0.425,-0.376,P<0.05)。结论 EBV感染患儿的临床症状和细胞免疫功能与病毒载量有关,有望应用于临床评估EBV感染的病情发展。 相似文献
26.
近年严重急性呼吸综合征冠状病毒2(severe acute respiratory syndrome corona virus 2,SARS-CoV-2)大流行对人类健康造成了威胁。研究表明,SARS-CoV-2对人类生育能力有潜在影响,对男性生育力的影响远大于女性。目前研究表明接种疫苗可能不会对人类的生育能力存在不利影响。感染SARS-CoV-2会不会发生性传播、垂直传播及母婴传播,从而对下一代产生影响,目前暂不清楚。尚需要从生殖医学科、传染病学科角度探讨SARS-CoV-2及其疫苗对生育的影响,并讨论可能存在的性传播、垂直传播和母婴传播,以提高对SARS-CoV-2及其疫苗的认识。 相似文献
27.
中国6个KM小鼠群体外形形态特征调查 总被引:3,自引:1,他引:2
对来自我国南方6个科研机构饲养的KM小鼠的外形进行了调查,测量了成年KM小鼠(每个机构20♂,20♀)的体全长、尾长和头体长3个主要外形指标。结果显示:各群体间在这3项指标上存在着不同程度的差异,表明中国KM小鼠的外形特征出现了一定程度的种群分化。 相似文献
28.
Louise B. Russell Sun-Young Kim Cristiana Toscano Ben Cosgriff Ruth Minamisava Ana Lucia Andrade Colin Sanderson Anushua Sinha 《Vaccine》2021,39(1):158-166
BackgroundThis paper compares cost-effectiveness results from two models of maternal immunization to prevent pertussis in infants in Brazil, one static, one dynamic, to explore when static models are adequate for public health decisions and when the extra effort required by dynamic models is worthwhile.MethodsWe defined two scenarios to explore key differences between static and dynamic models, herd immunity and time horizon. Scenario 1 evaluates the incremental cost/DALY of maternal acellular pertussis (aP) immunization as routine infant vaccination coverage ranges from low/moderate up to, and above, the threshold at which herd immunity begins to eliminate pertussis. Scenario 2 compares cost-effectiveness estimates over the models’ different time horizons. Maternal vaccine prices of $9.55/dose (base case) and $1/dose were evaluated.ResultsThe dynamic model shows that maternal immunization could be cost-saving as well as life-saving at low levels of infant vaccination coverage. When infant coverage reaches the threshold range (90–95%), it is expensive: the dynamic model estimates that maternal immunization costs $2 million/DALY at infant coverage > 95% and maternal vaccine price of $9.55/dose; at $1/dose, cost/DALY is $200,000. By contrast, the static model estimates costs/DALY only modestly higher at high than at low infant coverage. When the models’ estimates over their different time horizons are compared at infant coverage < 90–95%, their projections fall in the same range.ConclusionsStatic models may serve to explore an intervention’s cost-effectiveness against infectious disease: the direction and principal drivers of change were the same in both models. When, however, an intervention too small to have significant herd immunity effects itself, such as maternal aP immunization, takes place against a background of vaccination in the rest of the population, a dynamic model is crucial to accurate estimates of cost-effectiveness. This finding is particularly important in the context of widely varying routine infant vaccination rates globally.Clinical Trial registryClinical Trial registry name and registration number: Not applicable. 相似文献
29.
《Vaccine》2022,40(5):706-713
BackgroundThe COVID-19 pandemic has disrupted healthcare, including immunization practice and well child visit attendance. Maintaining vaccination coverage is important to prevent disease outbreaks and morbidity. We assessed the impact of the COVID-19 pandemic on pediatric and adolescent vaccination administration and well child visit attendance in the United States.MethodsThis cross-sectional study used IBM MarketScan Commercial Database (IMC) with Early View (healthcare claims database) and TriNetX Dataworks Global Network (electronic medical records database) from January 2018–March 2021. Individuals ≤ 18 years of age who were enrolled during the analysis month of interest (IMC with Early View) or had ≥ 1 health encounter at a participating institution (TriNetX Dataworks) were included. We calculated the monthly percent difference between well child visit attendance and vaccine administration rates for 10 recommended pediatric/adolescent vaccines in 2020 and 2021 compared with 2018–2019. Data were stratified by the age groups 0–2 years, 4–6 years, and 9–16 years.ResultsIn IMC with Early View, the average monthly enrollment for children 0–18 years of age was 5.2 million. In TriNetX Dataworks, 12.2 million eligible individuals were included. Well child visits and vaccinations reached the lowest point in April 2020 compared with 2018–2019. Well child visit attendance and vaccine administration rates were inversely related to age, with initial reductions highest for adolescents and lowest for ages 0–2 years. Rates rebounded in June and September 2020 and stabilized to pre-pandemic levels in Fall 2020. Rates dropped below baseline in early 2021 for groups 0–2 years and 4–6 years.ConclusionsWe found substantial disruptions in well child visit attendance and vaccination administration for children and adolescents during the COVID-19 pandemic in 2020 and early 2021. Continued efforts are needed to monitor recovery and catch up to avoid outbreaks and morbidity associated with vaccine-preventable diseases. 相似文献
30.
Neutropenia, fever, and infection 总被引:5,自引:0,他引:5
A E Brown 《The American journal of medicine》1984,76(3):421-428
With the advances in the management of various neoplastic diseases and subsequent improvement in "disease-free" states, complications of therapy--particularly, infectious complications--have evolved as stumbling blocks to survival. Among neutropenic (absolute neutrophil count below 1,000/mm3) patients with cancer, infection is the major autopsy-determined cause of death. With expected "cure rates" of childhood leukemia approaching 60 to 70 percent, it seems unreasonable to lose such patients to an infectious cause of death, yet this, indeed, happens. The purpose of this review is to (1) define the magnitude of the problem; (2) describe the various agents responsible for infections in neutropenic patients; (3) attempt to more sharply define degrees of neutropenia and mechanical defenses; and (4) consider various approaches to studying and treating these infections. 相似文献