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31.
The effects of freezing on the proteolysis of beef during storage at 4°C after being thawed was investigated.

A sarcoplasmic 32-kDa protein in frozen as well as unfrozen beef decreased rapidly during storage at 4°C, and a more than 100-kDa protein appeared in both beef samples. And the increment of peptides in the frozen beef during the storage at 4°C was larger than that in the unfrozen beef, suggesting that the proteolysis was faster during the storage of the former than the latter. However, its increment in the frozen beef for 10 weeks during the storage at 4°C became smaller than that of the one frozen for less than 5 weeks.

To discover an indicator for evaluation of the conditioning of frozen and unfrozen beef, peptides produced during the storage of beef at 4°C were surveyed. A peptide, APPPPAEVPEVHEEV, was detected and seemed to be available as an indicator in the conditioning of beef.  相似文献   
32.
目的分析慢性支气管炎急性加重期病原菌的类型、分布以及药物敏感性试验的情况。方法收集2004年1月至2007年12月我所住院的慢性支气管炎急性加重期患者共送检168例次痰标本进行培养和药物敏感试验。结果从痰液中共检出156株需氧菌,其中革兰阴性菌93株(59.62%),革兰阳性菌41株(26.28%),真菌22株(14.1%);在革兰阴性菌中,以克雷伯菌属为主,占总分离率的21.15%(33/156),其次是铜绿假单胞菌,分离出24株(15.38%);革兰阳性菌则以金黄色葡萄球菌及肺炎链球菌居多。感染以革兰阴性杆菌为主,对11种临床常用的抗生素敏感率较高的是亚胺培南,其次是氨基糖苷类。结论本试验可提高对慢性支气管炎的临床诊断,根据其病原学特点合理使用抗菌药物。  相似文献   
33.
目的探讨硫酸特布他林、布地奈德联合雾化吸入对婴幼儿毛细支气管炎的疗效。方法将142例患者随机分为试验组(72例)与对照组(70例)。对照组进行抗病毒吸氧、止咳化痰等常规治疗;试验组在常规治疗的基础上,加用雾化吸入硫酸特布他林、布地奈德雾化液,比较两组疗效。结果试验组的疗效明显优于对照组(P〈0.01)。结论硫酸特布他林雾化液、布地奈德混悬液吸入能较快地改善呼吸功能,有效改善毛细支气管炎患儿症状,值得在基层医院推广。  相似文献   
34.
根据GenBank上发表的IBV S2基因序列,自行设计了两对引物,分别扩增SD/97/02株S2基因的上游1100bp部分和下游的900bp部分,两段序列拼接后包含了S2全基因的序列。将此两段分别克隆入pGEM T-easy载体,测序后将序列用分析软件DNASTAR和网上的BLAST软件进行分析,结果表明,S2基因比S1基因相对来说更保守,位于氨基酸第560-600位很有是与囊膜锚着的部位,而S2与S1的交界处以HRRRR为特征,这不同地常规的RRF/SRR。  相似文献   
35.
Cold‐inducible RNA‐binding protein (CIRP) is a stress‐response protein that is expressed in various types of cells and acts as an RNA chaperone, modifying the stability of its targeted mRNA. Intracellular CIRP could also be released into extracellular space and once released, extracellular CIRP (eCIRP) acts as a damage‐associated molecular pattern (DAMP) to induce and amplify inflammation. Recent studies have found that eCIRP could promote acute lung injury (ALI) via activation of macrophages, neutrophils, pneumocytes and lung vascular endothelial cells in context of sepsis, haemorrhagic shock, intestinal ischemia/reperfusion injury and severe acute pancreatitis. In addition, CIRP is also highly expressed in the bronchial epithelial cells and its expression is upregulated in the bronchial epithelial cells of patients with chronic obstructive pulmonary diseases (COPD) and rat models with chronic bronchitis. CIRP is a key contributing factor in the cold‐induced exacerbation of COPD by promoting the expression of inflammatory genes and hypersecretion of airway mucus in the bronchial epithelial cells. Besides, CIRP is also involved in regulating pulmonary fibrosis, as eCIRP could directly activate and induce an inflammatory phenotype in pulmonary fibroblast. This review summarizes the findings of CIRP investigation in respiratory diseases and the underlying molecular mechanisms.  相似文献   
36.
易祖志广  黄文珊 《蛇志》1997,9(3):60-62
55岁以下中青年肺心病90例与同期收治的60岁以上老年肺心病90例作对照,发现中青年组有如下特点:①原发疾病两组均以慢性支气管炎多见,但中青年组肺结核、支气管扩张常见,合并高血压、冠心病少见。②主要症状、体征以咯血、杵状指、体温大于37℃多见,神志改变、早搏较老年组少见。③白细胞总数增高、痰培养G+球菌多见。G-杆菌少见。④血气分析低氧血症多见。⑤心电图以右室肥厚多见,与X线右室肥厚多相一致。⑥多脏器衰竭(MSOF)为主要死因  相似文献   
37.
鸡传染性支气管炎(Infectious Bronchitis,IB)是由传染性支气管炎病毒(Infectious Bronchitis Virus,IBV)引起的鸡的一种急性、高度接触性传染病.该病是危害全球养禽业的重要传染病之一[1,2].其感染的主要特征是气管啰音、咳嗽和打喷嚏.此外,该病还可以引起蛋鸡产蛋量下降和蛋品质下降.雏鸡可由于呼吸道或肾脏的感染而死亡.虽然疫苗的使用对IB的流行起到了一定的预防和控制作用,但由于IBV血清型众多,不同血清型毒株之间具有较小的交叉保护性甚至无交叉保护性.因此,IB目前仍在免疫鸡群和非免疫鸡群发生和传播,给养禽业造成了严重的经济损失.  相似文献   
38.
【目的】传染性支气管炎病毒(Infectious bronchitis virus,IBV)主要引起鸡群呼吸道与肾脏疾病,是影响养禽业重要的病毒性病原之一。了解我国IBV的流行及基因重组情况。【方法】收集GenBank中我国2002?2016年间分离的92株IBV S1基因及55株IBV基因组序列,并对这些序列进行比对分析。【结果】IBV S1基因序列分析结果表明,2002?2016年间我国流行的92株IBV可以分为13个基因型,包括QX、4/91、Mass、tl/CH/LDT3/03、CK/CH/LSC/99I、TW-I、TW-II、TC07-2、Ck/CH/LDL/97I、N1/62-associated、Arkansas、New-I及一个新鉴定的基因分支New-II。值得注意的是,属于美国相关基因分支的ck/CH/LSD/110712已在我国出现。RDP4方法进行重组分析显示,新出现的基因分支New-II病毒S1基因来源于tl/CH/LDT3/03型与QX型毒株重组,我国2002?2016年间流行的55株IBV中有52株IBV基因组存在重组事件,其中25个IBV分离株基因组中发现有疫苗型(Mass,tl/CH/LDT3/03及4/91型等)病毒基因组片段的重组,这一结果在SimPlot分析中进一步得到确认。【结论】根据生物信息学分析结果,证明流行于我国的IBV基因型众多,疫苗毒株基因频繁参与了IBV基因重组,导致IBV新的基因型或变异株出现,提示在防控IB时要注意合理使用IBV疫苗。  相似文献   
39.
40.

Background

The GOLD classification of COPD severity introduces a stage 0 (at risk) comprising individuals with productive cough and normal lung function. The aims of this study were to investigate total mortality risks in GOLD stages 0–4 with special focus on stage 0, and furthermore to assess the influence of symptoms of chronic bronchitis on mortality risks in GOLD stages 1–4.

Method

Between 1974 and 1992, a total of 22 044 middle-aged individuals participated in a health screening, which included a spirometry as well as recording of respiratory symptoms and smoking habits. Individuals with comorbidity at baseline (diabetes, stroke, cancer, angina pectoris, or heart infarction) were excluded from the analyses. Hazard ratios (HR 95% CI) of total mortality were analyzed in GOLD stages 0–4 with individuals with normal lung function and without symptoms of chronic bronchitis as a reference group. HR:s in smoking individuals with symptoms of chronic bronchitis within the stages 1–4 were calculated with individuals with the same GOLD stage but without symptoms of chronic bronchitis as reference.

Results

The number of deaths was 3674 for men and 832 for women based on 352 324 and 150 050 person-years respectively. The proportion of smokers among men was 50% and among women 40%. Self reported comorbidity was present in 4.6% of the men and 6.6% of the women. Among smoking men, Stage 0 was associated with an increased mortality risk, HR; 1.65 (1.32–2.08), of similar magnitude as in stage 2, HR; 1.41 (1.31–1.70). The hazard ratio in stage 0 was significantly higher than in stage 1 HR; 1.13 (0.98–1.29). Among male smokers with stage 1; HR: 2.04 (1.34–3.11), and among female smokers with stage 2 disease; HR: 3.16 (1.38–7.23), increased HR:s were found in individuals with symptoms of chronic bronchitis as compared to those without symptoms of chronic bronchitis.

Conclusion

Symptoms fulfilling the definition of chronic bronchitis were associated with an increased mortality risk among male smokers with normal pulmonary function (stage 0) and also with an increased risk of death among smoking individuals with mild to moderate COPD (stage 1 and 2).  相似文献   
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