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61.
62.
Abstract Exercise induced asthma is a common complaint and the prevalence appears to be increasing worldwide. Once confined to the research domain of university teaching hospitals, the study of EIA has extended into the school playground, defence force establishments and sports institutions. Standardized protocols have been developed to study EIA in the laboratory and in the field. A surrogate challenge using eucapnic or isocapnic hyperventilation with dry air is becoming popular because it has advantages over exercise, at least for adults. The stimulus that leads the airways to narrow is caused by the inhalation of dry air during hyperventilation and exercise, during which water is evaporated from the airways in order to condition the inspired air. The mechanism whereby the airways narrow is thought to be due to the dehydrating effects of water loss, particularly in relation to its potential to cause the airways to become hyperosmolar. Mast cell mediators such as histamine and the leucotrienes are probably involved in EIA because specific antagonists reduce severity. As a result of the osmotic theory of EIA, studies were carried out to determine whether subjects with EIA were sensitive to the effects of increasing airway osmolarity by inhalation of hyperosmolar aerosols of sodium chloride. A challenge protocol using an aerosol of 4.5% sodium chloride, generated from an ultrasonic nebulizer, has been used to identify persons with asthma and to assess response to drug therapy. There are many similarities between responses to exercise, hyperventilation and hypertonic saline in the physiological and biochemical responses and the responses to drugs. Challenge with hypertonic saline is easier and cheaper to use because expensive equipment and a source of dry air is not required as with exercise or hyperventilation. The ability to obtain a dose-response curve rather than a single response and the ability to collect inflammatory cells at the same time make challenge with hypertonic saline an attractive technique to study patients suspected of having asthma.  相似文献   
63.
目的评价小剂量聚乙二醇干扰素α-2b联合利巴韦林治疗慢性丙型病毒性肝炎的疗效和安全性.方法192例慢性丙型肝炎患者随机分为两组:聚乙二醇干扰素α-2b 0.5μg/kg每周一次联合利巴韦林750~1050 mg/d,或普通干扰素α-2b 3 MIU每周3次联合利巴韦林750~1050 mg/d.疗程48周,治疗结束后随访24周.结果聚乙二醇干扰素α-2b联合利巴韦林治疗的持续病毒学应答率为53.8%,而普通干扰素α-2b联合利巴韦林治疗的持续病毒学应答率为58.1%,两组持续病毒学应答率相当(P=0.966).聚乙二醇干扰素α-2b治疗组的药物相关性不良反应发生率为100%,而普通干扰素α-2b治疗组的不良反应发生率为95.2%,两组间差异有统计学意义(P=0.033).但是没有与干扰素α-2b聚乙二醇化相关的特有的新的不良反应发生.结论小剂量聚乙二醇干扰素α-2b联合利巴韦林治疗慢性丙型肝炎的疗效和安全性与普通干扰素α-2b联合利巴韦林治疗的疗效和安全性相当.  相似文献   
64.
INTRODUCTION Retreatment of hepatitis C patients who relapsed after recombinant interferon (rIFN) monotherapy has a fair rate of success when ribavirin is added to the original protocol. About 30% of patients infected with hepatitis C virus (HCV) genotype…  相似文献   
65.
AIM:To conduct a multicentre retrospective review of virological response rates in Asians infected with genotype 1 chronic hepatitis C(CHC) treated with combination interferon and ribavirin and then to compare their responses to that among Caucasians.
METHODS:Asian patients infected with genotype 1 CHC treated at 4 Australian centres between 2001 to 2005 were identified through hospital databases.Baseline demographic characteristics,biochemical,virological and histological data and details of treatment were collected.Sustained virological responses(SVR) in this cohort were then compared to that in Caucasian subjects,matched by genotype,age,gender and the stage of hepatic fibrosis.
RESULTS:A total of 108 Asians with genotype 1 CHC were identified.The end of treatment response(ETR) for the cohort was 79% while the SVR was 67%.Due to the relatively advanced age of the Asian cohort,only sixty-four subjects could be matched with Caucasians.The ETR among matched Asians and Caucasians was 81% and 56% respectively(P=0.003),while the SVR rates were 73% and 36%(P 〈0.001) respectively.This difference remained significant after adjusting for other predictive variables.
CONCLUSION: Genotype 1 CHC in Asian subjects is associated with higher rates of virological response compared to that in Caucasians.  相似文献   
66.
The relative distributions of ventilation as measured by 99Tc-sulfur colloid aerosol deposition and pulmonary perfusion (measured with radiolabeled microspheres) were determined in 12 preterm lambs that were delivered at 138 days gestational age and ventilated for 4 hrs. To verify that unventilated lung segments in these lambs would have decreased perfusion, a balloon catheter was placed in a major bronchus either at birth or after 2 hrs of ventilation. This catheter prevented ventilation of 24.5 +/- 3.2% of the lung tissue. After 4 hrs of ventilation, the lambs were sacrificed and the lungs were divided into about 60 1-g pieces. Apart from the occluded, atelectatic segments, the lungs were visually well aerated with only 5.3 +/- 1.8% of the nonobstructed lungs being spontaneously atelectatic. There was a 66.5 +/- 0.07% decrease in blood flow to the area of lung made atelectatic by the balloon. The blood flow also was decreased to lung regions assessed to be spontaneously atelectatic. No 99Tc-sulfur colloid was recovered from balloon-occluded lung regions, and less 99Tc-sulfur colloid was found in the spontaneously atelectatic areas than in aerated lung regions. There were significant correlations (P less than 0.001) between pulmonary blood flow and aerosol recovery in each of the 12 animals. Premature lambs had a wide variability in ventilation and perfusion, but the relative ventilation to perfusion ratio was regulated to minimize the intrapulmonary shunt.  相似文献   
67.
BACKGROUND/AIMS: We performed a randomized trial on pegylated interferon alfa-2a (Peg-IFNalpha) monotherapy vs Peg-IFNalpha and ribavirin in non-cirrhotic liver transplant recipients with recurrent hepatitis C. METHODS: Forty-two patients transplanted for HCV-related cirrhosis 12-96 months earlier were randomized to Peg-IFNalpha monotherapy (180 microg weekly) or Peg-IFNalpha and ribavirin, up to the maximum tolerated dose, for 48 weeks. RESULTS: Early virological response (EVR, i.e., HCV-RNA2 log drop at week 12) occurred in 76% of the monotherapy and 71% of the combination groups, respectively (intention-to treat). Sustained virological response (SVR) occurred in 8 (38%) and 7 (33%) patients, respectively. EVR had a positive predictive value for SVR of 50% and 47%, respectively, and a 100% negative predictive value in both groups. Six drop-outs occurred in the monotherapy (including 3 rejections) and 7 in the combination groups (including one rejection). Peg-INFalpha dose was reduced in 7 and 8 patients, respectively. The average daily dose of ribavirin was 435 mg/day. CONCLUSIONS: Peg-IFNalpha-2a, with or without ribavirin, induces SVR in one-third of transplant recipients with recurrent hepatitis C. Treatment cessation is indicated in patients without EVR. The low SVR rate is mainly due to inability to sustain full doses of antivirals and lack of the booster effect of ribavirin.  相似文献   
68.
AIM: The clinical significance of co-infection of SENV-D among patients with chronic hepatitis C (CMC) and response of both viruses to combination therapy with high-dose interferon-alfa (IFN) plus ribavirin remain uncertain and are being investigated. METHODS: Total 164 (97 males and 67 females, the mean age 48.1±11.4 years, range: 20-73 years, 128 histologically proved) naive CMC patients were enrolled in this study. SENV-D DNA was tested by PCR method. Detection of serum HCV RNA was performed using a standardized automated qualitative RT-PCR assay (COBAS AMPLICOR HCV Test, version 2.0). HCV genotypes la, 1b, 2a, 2b, and 3a were determined by using genotype-specific primers. Pretreatment HCV RNA levels were determined by using the branched DNA assay (Quantiplex HCV RNA 3.0). There are 156 patients receiving combination therapy with IFN 6 MU plus ribavirin for 24 wk and the response to therapy is determined. RESULTS: Sixty-one (37.2%) patients were positive for SENV-D DNA and had higher mean age than those who were negative (50.7±10.6 years vs46.6±11.6 years, P= 0.026). The rate of sustained viral response (SVR) for HCV and SENV-D were 67.3% (105/156) and 56.3% (27/48), respectively. By univariate analysis, the higher rate of SVR was significantly related to HCV genotype non-1b (P<0.001), younger ages (P = 0.014), lower pretreatment levels of HCV RNA (P = 0.019) and higher histological activity index (HAI) score for intralobular regeneration and focal necrosis (P= 0.037). By multivariate analyses, HCV genotype non-lb, younger age and lower pretreatment HCV RNA levels were significantly associated with HCV SVR (odds ratio (OR)/95% confidence interval (CI): 12.098/0.02-0.19, 0.936/0.890-0.998, and 3.131/1.080-9.077, respectively). The SVR of SENV-D was higher among patients clearing SENV-D than those who had viremia at the end of therapy (P= 0.04). CONCLUSION: Coexistent SENV-D infection, apparently associated with higher ages, is found in more than one-third Taiwanese CHC patients. Both HCV and SENV-D are highly susceptible to combination therapy with high-dose IFN and ribavirin and SENV-D co-infection does not affect the HCV response. HCV genotype, pretreatment HCV RNA levels and age are predictive factors for HCV SVR.  相似文献   
69.
目的研究快乐护理及图文诱导在学龄前儿童肺炎雾化吸入治疗中的应用效果。方法选取2018年3月~2019年8月我科肺炎雾化吸入的学龄前儿童112例,按照就诊先后顺序进行编号,单号为观察组,双号为对照组,各56例。对照组采用常规护理方法。观察组采用快乐护理及图文诱导干预。比较两组快乐感受、吸入依从性、治疗效果和家属满意度。结果观察组雾化吸入总有效54例(96.43%),高于对照组的45例(80.36%),差异有统计学意义(P<0.05);积极情绪评分高于对照组、消极情绪评分低于对照组,差异均有统计学意义(P<0.05)。雾化吸入依从55例(98.21%),高于对照组的45例(80.36%);家属满意56例(100.0%),高于对照组的46例(82.14%),差异均有统计学意义(P<0.05)。结论快乐护理及配合图文诱导通过改善学龄前儿童雾化吸入依从性和满意度,有助于提高雾化吸入治疗效果,从而促进病情好转,是一种可行、有效的护理对策。  相似文献   
70.
目的建设空气消毒专用实验室,完善消毒产品评价技术平台。方法通过科学的工艺设计和精确的施工,完成了军事医学科学院消毒检测中心空气消毒实验室建设。结果在静态环境条件下经过净化处理,该实验室主要指标均符合国家设计和施工及验收规范。2个气雾室内和单独气雾柜内温度在18℃~25℃范围内可调,相对湿度为30%~60%范围可调;送风量为254~1 402 m3/h;换气次数为15~70次/h;噪声为48.1 dB~58.7 dB;照度262 lx~599 lx;洁净度为273~1865个/L;静压差+11 Pa~+16 Pa。结论本所设计建造的空气消毒实验室建筑布局和硬件设备以及各种洁净指标均符合设计要求。  相似文献   
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