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71.
重症甲型H1N1流感是甲型H1N1流感病毒侵袭肺脏而产生的一种急性呼吸道传染性疾病,患者表现为持续高热、剧烈咳嗽、痰多、胸闷、口唇发紫,甚至出现呼吸衰竭及多器官功能损伤,导致死亡。孕产妇处于低免疫状态,如感染甲型H1N1流感病毒,容易发展成为肺炎型或重症甲型H1N1流感。  相似文献   
72.
BackgroundVarious serosurveys and studies were conducted globally on pandemic influenza. H1N1 virus reported so far provides ample evidence of differing perspectives, regarding its epidemiology especially with regard to prevalence, populations groups, and behaviour related to vaccine acceptance. A multigroup, cross-sectional survey among 658 healthy subjects was carried out, in Pune among students, health-care workers (HCWs), and soldiers to assess the seroprevalence of pandemic influenza H1N1 virus and its associated factors.MethodsThe total sample size, based on forecasted prevalence of 33%, worked out to be 640. We studied 658 subjects including 103 students, 201 HCWs, and 354 serving soldiers. The sample for each group was selected from the respective study population by simple random sampling using a random number table. Haemagglutination inhibition test was carried out at the National Institute of Virology.ResultsThe overall seroprevalence of pandemic influenza H1N1 (2009) virus was found to be 46.5% (95% confidence interval 42.6–50.4) which was adjusted to 39.4% after excluding those vaccinated. The availability of vaccine for high-risk group such as HCWs did not find much favour with the HCWs who did not accept vaccine for various reasons. Whereas only one student was vaccinated, 21.4% of HCWs and 32.5% of soldiers were vaccinated.ConclusionBased on high seroprevalence of antibodies against H1N1 virus during pandemic, vaccination of general population is not recommended. However, high-risk groups and HCWs need to be protected with flu vaccine. There is a need to encourage HCWs for accepting vaccination.  相似文献   
73.
ObjectiveTo survey avian influenza A viruses (AIVs) in the environment and explore the reasons for the surge in human H7N9 cases.MethodsA total of 1,045 samples were collected from routine surveillance on poultry-related environments and 307 samples from human H7N9 cases-exposed environments in Henan from 2016 to 2017. The nucleic acids of influenza A (Flu A), H5, H7, and H9 subtypes were detected by real-time polymerase chain reaction.ResultsA total of 27 H7N9 cases were confirmed in Henan from 2016 to 2017, 24 had a history of live poultry exposure, and 15 had H7N9 virus detected in the related live poultry markets (LPMs). About 96% (264/275) Flu A positive-environmental samples were from LPMs. H9 was the main AIV subtype (10.05%) from routine surveillance sites with only 1 H7-positive sample, whereas 21.17% samples were H7-positive in H7N9 cases-exposed environments. Samples from H7N9 cases-exposed LPMs (47.56%) had much higher AIVs positive rates than those from routine surveillance sites (12.34%). The H7+H9 combination of mixed infection was 78.18% (43/55) of H7-positive samples and 41.34% (43/104) of H9-positive samples.ConclusionThe contamination status of AIVs in poultry-related environments is closely associated with the incidence of human infection caused by AIVs. Therefore, systematic surveillance of AIVs in LPMs in China is essential for the detection of novel reassortant viruses and their potential for interspecies transmission.  相似文献   
74.
BACKGROUND: The incidence and patterns of nodal spread in previously irradiated N0 necks are not well defined. Therefore, the safety and efficacy of selective neck dissection (SND) in this patient population is not well established. In a previous report from our institution, SND in irradiated patients with recurrent disease at the primary site but clinically negative necks resulted in excellent tumor control in the neck. The objective of this study is to validate our initial observations in a larger sample of patients with longer follow-up. METHODS: A retrospective chart analysis of patients previously treated with primary radiation therapy or chemoradiotherapy for squamous cell carcinoma (SCC) of the head and neck between January 1997 and June 2003 was performed. Patients with recurrent or persistent disease at the primary site or a second primary head and neck SCC, with no clinical or radiologic disease in the neck, who underwent surgical salvage with resection of the primary site along with a site-specific SND were analyzed. Patients who remained disease free at the primary site were analyzed for regional control after SND. RESULTS: Sixty-nine patients underwent a total of 96 site-specific SNDs. The mean age was 64.1 years (range, 39-91 years). There was histologically positive nodal disease in 17 of 69 patients (25%), and 22 of 96 necks (23%). Fifty-three patients had at least a 12-month follow-up. The mean follow-up was 23.3 months (range, 1-96 months). Of the patients with 1-year of follow-up, six patients died from recurrence at the primary site, and nine died from distant metastasis. There were no cases of neck recurrence with the primary site controlled. All patients who had more than two positive nodes had recurrence either at the primary site or distant metastasis. CONCLUSIONS: Our results confirm that the patterns of lymphatic spread are not affected by radiation. We conclude that SND is oncologically safe in the management of the N0 irradiated neck and that the finding of more than two positive nodes predicts a poor outcome.  相似文献   
75.
Epidemiological outbreak investigations were conducted in highly pathogenic avian influenza virus of the subtype H5N8 (HPAIV H5N8)‐affected poultry holdings and a zoo to identify potential routes of entry of the pathogen via water, feedstuffs, animals, people, bedding material, other fomites (equipment, vehicles etc.) and the presence of wild birds near affected holdings. Indirect introduction of HPAIV H5N8 via material contaminated by infected wild bird seems the most reasonable explanation for the observed outbreak series in three commercial holdings in Mecklenburg‐Western Pomerania and Lower Saxony, while direct contact to infected wild birds may have led to outbreaks in a zoo in Rostock and in two small free‐range holdings in Anklam, Mecklenburg‐Western Pomerania.  相似文献   
76.

OBJECTIVE

To examine the correlation between partial bladder outlet obstruction (PBOO) and bladder carcinogenesis.

MATERIALS AND METHODS

Female Wistar rats (6 weeks old) were divided into three groups of 10 each: group 1 was exposed to n‐butyl‐n‐butanol nitrosamine (BBN, a carcinogen) in drinking water for 8 weeks; group 2 had PBOO induced surgically after exposure to BBN for 8 weeks; group 3 had a sham operation and the rats drank normal water (control group). After 20 weeks, all of the rats were killed humanely and their bladders analysed.

RESULTS

There were no significant differences in body weight among the groups. The bladder weight of group 2 was significantly greater than either group 1 or group 3. Histopathologically, bladder smooth muscle hypertrophy was the major cause of the increased bladder weight for group 2. In group 2 there were increases in bladder wall thickness and many nipple‐shaped urothelial tumours. Basic fibroblast growth factor and hypoxia‐inducible factor‐1α expression were significantly greater in group 2 than in groups 1 and 3.

CONCLUSIONS

Exposure of the bladder to carcinogens during bladder hyperplasia and hypertrophy induced by PBOO results in a greater incidence of superficial bladder carcinoma.  相似文献   
77.
甲型H1N1流感是由变异后的甲型H1N1流感病毒引起的急性呼吸道传染病。2009年5月30日,杭州市第六人民医院收治浙江省首例甲型H1N1流感患者,6月14日收治第2例。由于是浙江省较早发现的甲型H1N1流感患者,受到相关媒体高度关注。2例患者在隔离期间均出现极强的抵触心理,不配合隔离及医护治疗,但经护理人员积极、耐心的心理疏导后,不良情绪有所改善,主动配合检查,接受治疗,一周后顺利出院。  相似文献   
78.
目的本研究旨在合成N-酰基高丝氨酸内酯(N-acyl-homoserine lactone,AHL)全抗原,为建立AHL免疫检测新方法奠定基础。方法以γ-丁内酯和高丝氨酸内酯为原料,经保护、缩合、脱保护、氧化等一系列反应,获得N-丁酰高丝氨酸内酯、N-己酰高丝氨酸内酯和含有化学交联活性基团的羧基丁酰高丝氨酸内酯半抗原衍生物,用核磁共振氢谱和质谱方法进行结构确证,并采用活泼酯法合成N-酰基高丝氨酸内酯全抗原。结果质谱与核磁共振氢谱分析结果与理论预测相同,表明成功合成目标产物N-丁酰(己酰)高丝氨酸内酯和羧基丁酰高丝氨酸内酯半抗原衍生物;紫外吸收光谱扫描结果显示半抗原AHL已分别与载体牛血清白蛋白和鸡卵白蛋白交联,成功制备其全抗原。结论本实验成功合成了N-酰基高丝氨酸内酯半抗原衍生物和全抗原,为制备AHL相应抗体奠定了基础。  相似文献   
79.
目的观察不同H5N1亚型禽流感病毒株空斑特性,对比研究不同空斑类型H5N1病毒致病性和复制能力差异。方法将不同稀释度的H5N1亚型禽流感病毒株分别接种于MDCK单层细胞,加盖营养琼脂,合适时间染色,观察不同H5N1亚型禽流感病毒株空斑形成特点,按照DullbeccoR的方法计算病毒PFU数;根据空斑大小进行挑选、纯化、筛选不同类型空斑病毒,测定这些病毒对Balb/c小鼠致病性差异和在MDCK细胞上复制差异。结果野生的人源H5N1禽流感病毒株在空斑形成上都存在不同程度的不均一性,空斑大小、形状差异明显:A/Vietnam/1194/2004(H5N1)以大圆形斑为主,夹杂少量小点状斑。A/Beijing/01/03(H5N1)大多数为中等大小空斑,并有少数针尖状斑。野生A/Vietnam/1194/2004经过分离纯化后,得到的两种空斑类型病毒在致病性和复制能力存在明显差异。结论野生的人源H5N1禽流感病毒株在空斑形成上都存在不同程度的不均一性,从野生病毒株中分离、纯化的大小斑病毒在致病性和复制能力上存在明显差异。  相似文献   
80.
目的从厦门海域单鳍电鳐的电器官中提取烟碱型乙酰胆碱受体(N2-AchR)纯品,用纯化的N2-AchR免疫Lewis大鼠,建立实验性自身免疫性重症肌无力(EAMG)动物模型。方法参照文献报道从电鳐电器官提取N2-AchR纯品,并采用SDS凝胶电泳蛋白定性鉴定及考马斯亮兰定蛋白含量;以纯提的蛋白主动免疫Lewis大鼠,共免疫3次,于末次免疫后第3日进行EAMG大鼠临床评分及攀网时间、肌电图、血清N2-AchRab含量、突触后膜上N2-AchR数目的检测。结果纯化的蛋白含量为1.097mg/ml(标准品为1mg/ml);EAMG模型组与佐剂组比较,攀网时间明显降低(P〈0.01);临床评分及肌电图第五个反应幅度衰减百分率显著升高(P〈0.01);血清N2-AchRab含量明显增加(P〈0.01);突触后膜上N2-AchR数目显著减少(P〈0.01)。结论从单鳍电鳐电器官纯提的N2-AchR蛋白成功诱导EAMG模型,为进一步研究重症肌无力创造了良好条件。  相似文献   
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