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41.
OBJECTIVES: To determine the spectrum of N and G genotypes of respiratory syncytial virus (RSV) causing respiratory tract infection and whether particular genotypes are associated with severity of infection. PATIENTS AND METHODS: Nasopharyngeal aspirates (NPAs) were obtained from 114 infants with acute respiratory tract infection due to RSV over two seasons. Viral mRNA was extracted from NPAs or cultured virus, reverse transcribed, and the cDNA amplified by the polymerase chain reaction using primers directed to parts of the N and G gene respectively. Amplicons were separately digested with four different restriction endonucleases for each gene. The fragments were separated by agarose gel, electrophoresis, and the electrophoretic patterns used to assign the various genotypes. Disease severity was assessed as very mild (upper respiratory tract signs only), mild (coryza and signs of lower respiratory tract infection), moderate (requiring nasogastric or intravenous fluids), and severe (requiring oxygen or ventilation). RESULTS: Five of the six known N genotypes were detected, but NP4 and NP2 were found most frequently. There was no association between N genotype and disease severity. Six G (SHL) genotypes were detected. Significantly (p = 0.04) more of the infants infected with the SHL2 genotype had severe or moderate disease. CONCLUSIONS: During the seasonal peaks of RSV respiratory tract infection at least 10 different RSV genotypes cocirculated. While there is no association between N genotypes and disease severity, infection with the SHL2 G genotype appears to result in moderate to severe disease. 相似文献
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Predicting readmission to hospital with asthma 总被引:2,自引:0,他引:2
D RAYMOND RL HENRY N HIGGINBOTHAM & M COORY 《Journal of paediatrics and child health》1998,34(6):534-538
44.
Bolontrade MF; Stern MC; Binder RL; Zenklusen JC; Gimenez-Conti IB; Conti CJ 《Carcinogenesis》1998,19(12):2107-2113
In this study we have analyzed the vascular response induced in the two-
stage carcinogenesis model in SENCAR mice. The role of angiogenesis has not
been explored in this model, which is the paradigm of multistage
carcinogenesis and a model for neoplastic lesions derived from exophytic
premalignant lesions (e.g. colon carcinoma, bladder papilloma). We
investigated if angiogenesis is involved in the formation of papillomas and
in the progression from papilloma to carcinoma. To this end we analyzed the
vasculature of normal and hyperplastic skin, focal epidermal hyperplasias
that are precursors of papillomas, papillomas at different stages and
squamous cell carcinomas. We also analyzed the vascularization of
papillomas induced in two strains of mice that differ in their
susceptibility to malignant progression. We show here that angiogenesis is
turned on in the earliest stages of papilloma formation. In late stages,
regardless of state of progression, the predominant response is an increase
in the size of blood vessels. Thus, in the SENCAR mouse model,
representative of exophytic tumors, the angiogenesis switch is a very early
event, probably mechanistically related to the development of the primarily
exophytic lesions. Therefore, the density of blood vessels cannot be used
as a predictor of malignant progression in this model.
相似文献
45.
Femmy M Bijnsdorp Allard J van der Beek Marjolein I Broese van Groenou Karin I Proper Swenneke G van den Heuvel Ccile RL Boot 《Scandinavian journal of work, environment & health》2022,48(3):190
ObjectivesThis study aims to provide insight into (i) how the combination of paid work and family care is longitudinally associated with gender-related differences in depressive symptoms and (ii) the role of work characteristics in this association.MethodsData were derived from STREAM, a Dutch prospective cohort study of older workers aged 45–64 years. Respondents were included if they were employed in at least one measurement between 2015 and 2017 (N=12 447). Mixed-models were applied to disentangle between-person (BP) and within-person (WP) effects of family caregiving on depressive symptoms. Analyses were stratified by gender. Work characteristics (social support, autonomy, emotional and mental workload) were separately added to the multivariable models.ResultsFor older employees, family caregiving was positively associated with depressive symptoms between and within persons for both women [BP B=0.80, 95% confidence interval (CI) 0.52–1.08; WP B=0.32, 95% CI 0.08–0.56] and men (BP B=0.75, 95% CI 0.45–1.05; WP B=0.25, 95% CI 0.01–0.48). Social support at work reduced the adverse effect of family care on depressive symptoms for women (BP) and men (BP and WP). Emotional workload partly explained the effect of family care for both women and men (BP).ConclusionsThe longitudinal association between family care and mental health was similar for male and female employees. Resources at work (ie, social support) could protect caregiving employees against depressive symptoms. More research is needed regarding the relative impact of the care context compared to the work context of working family caregivers. 相似文献
46.
为了寻找毒性低、增敏作用强的乏氧细胞放射增敏剂,设计并合成了一系列5-溴-,5-甲基-,和5-未取代的3-硝基-1,2,4-三唑-1-乙酰胺类化合物,用HeLaS3细胞进行了体外试验。结果表明5-溴取代衍生物的增敏作用强于相应的5-甲基-或5-未取代的硝基三唑衍生物,但是它们的毒性亦增大。修饰1位乙酰胺侧链也可以改变化合物的增敏作用和亲脂性。在所测定的化合物中TA-101[2-(3-硝基-1-三唑基)乙酰胺]由于有高的增敏作用和低亲脂性,可能是一个有希望的放射增敏剂。 相似文献
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