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Nasal swab from patients with acute flu-like illness were evaluated for the presence of respiratory viruses in the Rhone-Alpes region of France from 1 October 1994 through 2 May 1995. The relative frequencies and seasonal distributions of the specific viruses were assessed. In addition, virus type was correlated with specific clinical signs and symptoms. During the study, 962 samples were collected by 75 medical practitioners participating in the Groupe Regional d'Observation de la Grippe surveillance network. One or more viruses were detected from 348 samples (36.1%), including 108 respiratory syncytial virus (RSV), 64 influenza virus A type H3N2, 47 influenza virus B, 64 coronavirus, 35 rhinovirus, 22 adenovirus, 5 enterovirus, and 3 parainfluenza-fluenza strains. There were 16 mixed infections. RSV infections peaked in the early winter, and influenza viruses A and B infections peaked during the late winter and early spring. There were two peaks of coronavirus infections (late fall and late winter). Other viruses were detected at lower levels throughout the study period. Patients from whom adenovirus was isolated were significantly more likely to have a fever of > 39.5 degrees C than were patients with other detectable viruses (P < 0.001). Furthermore, there was a significant correlation between influenza and cough (P < 0.01) and RSV and bronchiolitis (P < .001). Thus, the current study defined the overall and relative frequencies of respiratory virus detection from nasal swab specimens in patients with an acute flu-like illness in the Rhone-Alpes region of France during a 7-month period. Correlation with clinical signs and symptoms and provisional conclusions regarding seasonality were also determined.  相似文献   
24.
OBJECTIVE: The increasing prevalence of HIV-1 transmission through heterosexual contacts and the growing number of immigrants from non-Western countries, where non-B subtypes and recombinant forms are prevalent, suggest the possible emergence in Italy of a new epidemic wave of HIV-1 non-B subtypes as well as recombinant forms. METHODS: The distribution of HIV-1 subtypes has been evaluated in 63 seropositive individuals residing in Italy, most of whom were infected through a sexual route during the last 5 years. A modified heteroduplex mobility assay (HMA) strategy, reverse HMA (rHMA), has been developed in our laboratory, allowing rapid identification of divergent-from-B-subtype isolates, which have been subsequently characterized by detailed molecular and phylogenetic analyses. RESULTS: Five samples show, on rHMA, an electrophoretic pattern compatible with a non-B subtype classification. Their phylogenetic analysis, performed on both env and gag regions, confirms the rHMA subtyping prediction, given that 3 samples fall into the "A-family" subtype and 2 into the G subtype. The 5 non-B-subtype HIV-1 isolates have been identified among 23 variants (prevalence, 21.74%) isolated during the 2000 to 2001 period in heterosexuals. In parallel, B-subtype isolates show high levels of intrasubtype nucleotide divergence, compatible with a constant HIV-1 molecular diversification. CONCLUSION: The Italian HIV-1 epidemic is still mostly attributable to the B subtype, which shows an increasing nucleotide heterogeneity. Heterosexual transmission and the interracial blending, however, are slowly introducing novel HIV-1 subtypes, and the data indicate that rHMA represents a powerful tool for HIV-1 biomolecular screening in epidemics characterized by a mono-/dual-subtype predominance.  相似文献   
25.
Head and neck squamous cell carcinoma is a disease associated with tobacco and alcohol abuse. There is evidence that the oncogenic human papillomavirus (HPV) may also be a risk for upper aerodigestive tract cancers. High-risk HPVs encode two early proteins, E6 and E7, that can bind to p53 and pRb, respectively, and induce its degradation or inactivation. The TP53 gene has a single polymorphism at codon 72 of exon 4 that encodes either arginine (Arg) or proline (Pro). The purpose of this study was to evaluate the role of HPV infection and TP53 polymorphism in head and neck cancer. We analyzed 50 tumors, as well swabs of oral mucosa from 142 control individuals, with a polymerase chain reaction technique. The prevalence of HPV in controls was 10.6% and in cancer specimens 16%. The frequency distribution of genotypes in controls was 50% Arg/Arg, 43% Arg/Pro and 7% Pro/Pro; in tumors, it was 52% Arg/Arg, 32% Arg/Pro, and 16% Pro/Pro. Contrary to the results of some studies on cervical cancer, no association between any TP53 genotype or allele and the development of head and neck cancer was observed, regardless of HPV status, except for the Pro/Pro genotype, which is associated with the absence of HPV. The arginine allele appears to protect against head and neck cancers. Also, the data showed that HPV infection results in no increased risk of developing head and neck tumors.  相似文献   
26.
目的 :观察五味子和头孢氨苄对大肠埃希氏菌和金黄色葡萄球菌的抑制作用。方法 :试管稀释法。结果 :五味子水煎剂 (1g/ml,pH =2 .8)对二株受试菌的MBC分别是 6 2 .5g/L和 31.2 5g/L ,而五味子水煎剂调pH为 7 0后 ,其MBC均大于 5 0 0g/L。头孢氨苄对大肠埃希氏菌的MIC和MBC分别是 4 88mg/L和 15 6 2 5mg/L ;对金黄色葡萄球菌的MIC和MBC分别是 2 44mg/L和 78 13mg/L。pH为 7 0的五味子联用头孢氨苄对大肠埃希氏菌的MBC分别为大于 2 5 0g/L和 15 6 2 5mg/L ,部分抑菌浓度指数为 1 5。结论 :pH为 2 8的五味子水煎剂有一定抑制致病菌作用 ;pH为 7 0的五味子水煎剂与头孢氨苄联用 ,两药呈现无关作用。  相似文献   
27.
血管内超声(IVUS)图像是观测血管内部结构的首选影像学手段,基于IVUS图像的内膜和中外膜边界的提取是实现冠脉粥样硬化精准诊断的前提和关键。针对IVUS图像结构复杂、对比度低、边界提取困难等问题,本研究提出一种基于改进TransUnet网络的分割方法。首先,针对IVUS图像边界提取难点,对边血管、血管分叉、导丝伪像、阴影等4种图像结构进行建模,并基于建模结果予以定向数据增强;而后,结合IVUS图像的环状结构分布特点,在TransUnet网络中提出了Polar-bias归纳偏置的策略,并对IVUS图像进行像素级的分类;最后,基于分类结果优化GVF snake模型的外力场,进而提取IVUS图像的内膜和中外膜边界。采用国际标准IVUS图像数据集(两组不同中心频率,共512幅图像)对算法进行评测,引入JMard距离(JM),Hausdorff距离(HD)和面积差异百分比(PAD)等3个评测指标,在数据集A中JM为0.87, HD为0.87, PAD为0.18,数据集B中JM为0.91, HD为0.25, PAD为0.08。实验结果表明,所提出的算法在两组数据集的内膜及中外膜提取问题中的表现均...  相似文献   
28.
Down syndrome regression disorder (DSRD) is a clinical symptom cluster of acute or subacute neurocognitive regression in otherwise health persons with Down syndrome. The objective of this study was to evaluate if adverse childhood experiences (ACEs) were more prevalent in children with DSRD than those with DS alone. A survey-based, cohort-based study was performed. Caregivers of individuals with DSRD with onset of symptoms between age 10 and 30 years and DS alone were administered the ACEs questionnaire via an online REDCap survey. A total of 159 responses were collected after excluding incomplete surveys and those not meeting criteria for DSRD. Individuals with DSRD were not more likely to experience ACEs (p = 0.18, 95% confidence interval [CI]: 0.43–1.17). In those with ACEs prior to the onset of symptoms, the median time prior was 7 months (interquartile range: 5–10). Individuals with DSRD were more likely to report three or more ACEs (52, 33%) compared to those with DS alone (39, 22%) (p = 0.02, 95% CI: 1.08–2.87). Exposure to ACEs were not predictive of response to particular therapeutic interventions although those with multiple ACEs 3 months prior to the onset of symptoms was associated with lower response rates to benzodiazepines and immunotherapy (p = 0.02, 95% CI: −3.64–−1.13). This study provides preliminary data that individuals with DSRD experience ACEs at a similar rate to individuals with only DS alone, although three or more ACEs, often preceding the onset of symptoms, was more prevalent in individuals with DSRD.  相似文献   
29.
  1. This study was aimed at characterizing ATP-induced rises in cytosolic free calcium ion, [Ca2+]i, in a population of rat striatal astrocytes loaded with the fluorescent Ca2+ probe Fura2, by means of fluorescence spectrometry.
  2. ATP triggered a fast and transient elevation of [Ca2+]i in a concentration-dependent manner. The responses of the purine analogues 2-methylthio-ATP (2-meSATP), adenosine-5′-O-(2-thiodiphosphate) (ADPβS), as well as uridine-5′-triphosphate (UTP) resembled that of ATP, while α,β-methylene-ATP (α,β-meATP) and β,γ-methylene-ATP (β,γ-meATP) were totally ineffective.
  3. Suramin (50 μM) had only a minor effect on the ATP response, whereas pyridoxal phosphate-6-azophenyl-2′,4′-disulphonic acid (PPADS) (5 μM) significantly depressed the maximum response.
  4. Extracellular Ca2+ did not contribute to the observed [Ca2+]i rise: removing calcium from the extracellular medium (with 1 mM EGTA) or blocking its influx by means of either Ni2+ (1 mM) or Mn2+ (1 mM) did not modify the nucleotide responses.
  5. Furthermore, after preincubation with 10 μM thapsigargin, the nucleotide-evoked [Ca2+]i increments were completely abolished. In contrast, 10 mM caffeine did not affect the responses, suggesting that thapsigargin-, but not caffeine/ryanodine-sensitive stores are involved.
  6. Both application of the G-protein blocker guanosine-5′-O-(2-thiodiphosphate) (GDPβS) (1 mM) and preincubation with pertussis toxin (PTx) (350 ng ml−1) partially inhibited the nucleotide-mediated responses. Moreover, the phospholipase C (PLC) inhibitor U-73122, but not its inactive stereoisomer U-73343 (5 μM), significantly reduced the ATP-evoked [Ca2+]i rise.
  7. In conclusion, our results suggest that, in rat striatal astrocytes, ATP-elicited elevation of [Ca2+]i is due solely to release from intracellular stores and is mediated by a G-protein-linked P2Y receptor, partially sensitive to PTx and coupled to PLC.
  相似文献   
30.
目的:探讨中西医结合治疗再生障碍性贫血的疗效。方法:采用中医补肾健脾,益气活血的克障汤,辅以西药综合治疗。结果:本组共治疗再生障碍性贫血30 例,经26 个月治疗,总有效率80% 。结论:中西医结合治疗疗效明显优于单纯使用西药组,早期诊断、早期治疗和坚持长期治疗是本病早日康复的关键。  相似文献   
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