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51.
Eosinophilic bronchitis without asthma can cause a persistent non-productive cough which is resistant to bronchodilator therapy. To understand the mechanism of the cough in this disorder, an animal model of eosinophilic bronchitis was developed. Guinea-pigs were treated with transnasal administration of polymyxin B or saline twice a week for 3 weeks. The number of eosinophils in bronchoalveolar lavage fluid increased in polymyxin B-treated animals when compared with those treated with saline. In addition, histological examination showed that the number of eosinophils infiltrated into the tracheal epithelium increased; injury to the tracheal epithelium was greater in polymyxin B-treated animals. The numbers of coughs induced by saline and each concentration of capsaicin (10–18, 10–16, 10–14M) were greater in the polymyxin B-treated animals. FK-224 (a neurokinin receptor antagonist) decreased the heightened cough reflex in this animal model of eosinophilic bronchitis. These findings suggest that neuropeptides, and particularly neurokinins, are involved in the heightened cough receptor sensitivity in eosinophilic bronchitis without asthma. This has implications for better understanding of this disorder and its treatment.  相似文献   
52.
早期营养对IUGR大鼠糖耐量和胰岛素敏感性的远期影响   总被引:3,自引:0,他引:3  
【目的】了解宫内发育迟缓(IUGR)和生后早期蛋白质营养不良对IUGR大鼠糖耐量和胰岛素敏感指数(ISI)及胰岛素抵抗指数(IRI)的远期影响。【方法】采用被动吸烟法制作IUGR大鼠动物模型,新生正常鼠仔102只和IUGR鼠仔105只随机分为4组:①正常对照组;②IUGR模型组;③正常大鼠低蛋白饮食组(CLP组);④IUGR大鼠低蛋白饮食组(SLP组)。观察各组大鼠在生后4周(幼年期)、12周(成年期)和48周龄(老年期)时糖耐量和胰岛素释放试验变化。【结果】①SLP组大鼠宫内发育迟缓和生后早期蛋白质营养不良其远期葡萄糖-胰岛素代谢功能受损明显,至48周时空腹血糖(5.2±1.4)mmol/L已升高,胰岛素(31. 2±3.4)mU/L水平明显升高,ISI(1.7±0.4)明显下降,IRI(8.7±1.8)明显升高,与正常对照组[(4.5±1.1)mmol/L,(12.9±1.0)mU/L和2.8±0.2,2.3±0.41比较均有显著性差异(P<0.05或P<0.01)。②CLP组大鼠生后早期单纯蛋白质营养不良的远期影响主要表现为糖负荷后胰岛素对血糖升高的应答分泌反应延迟和糖耐量减低。③IUGR模型组大鼠生后即给予正常营养供给,其葡萄糖-胰岛素代谢紊乱的程度减轻,但仍有糖耐量减低。【结论】在宫内和/或生后早期机体发育的关键时期,蛋白质营养不良将对葡萄糖-胰岛素代谢功能产生长期的不良影响,主要表现为糖耐量减  相似文献   
53.
The aim of the present work was to investigate the role of GABA and glycine, the two main inhibitory neurotransmitters in the retina, in the spectral sensitivity coding under conditions of light adaptation. To study this question, spectral sensitivity curves, based on the turtle ERG responses to stimuli of different wavelengths, were constructed. The spectral sensitivity curves, obtained before and during treatment with picrotoxin (PT), a GABAA antagonist, or with strychnine (ST), a glycine antagonist, were compared. Both PT and ST increased the b- and d-wave absolute sensitivity in a wavelength-dependent manner. PT significantly changed the shape of the b- and d-wave spectral sensitivity curves and the latter lost their peaks. It is concluded that, under conditions of light adaptation, GABA and glycine took part in the formation of the b- and d-wave spectral sensitivity curves, that both of them exerted an effect on the gain and that, furthermore, GABA had a well pronounced effect on the tuning of the spectral sensitivity curves.  相似文献   
54.
目的:探讨缬沙坦与吲达帕胺联合应用对原发性高血压(EH)患者动态血压及胰岛素敏感性的影响。方法:对65例EH患者于治疗前和治疗24周后分别进行动态血压监测(ABPM)和胰岛素敏感性测定。结果:治疗后24h平均pSB、pDB,血压负荷较治疗前均显著降低(P<0.01)。治疗后血压昼夜节律消失者8例,较治疗前42例显著减少(P<0.01)。治疗后各时点胰岛素与血糖比值(I/G)均明显下降(P<0.01),治疗后胰岛素敏感指数(ISD)显著增高(P<0.01);治疗后葡萄糖 耐量试验120min和180min两个时点C/I比值比治疗前显著增高(P<0.01-0.05)。结论:缬沙坦与吲达帕胺联合应用可显著降低EH患者动态血压水平和血压负荷,改善血压昼夜节律,显著改善胰岛素敏感性。  相似文献   
55.
56.
目的 研究虹膜夹型有晶状体眼人工晶状体(iris-claw phakic intraocular lens,ICPIOL)植人术后对比敏感度(contrastsensitivity,CS)的变化。方法 2005年5月至12月于温州医学院附属眼视光医院和中山大学中山眼科中心接受ICPIOL(Verisyse,美国AMO公司)植入术的高度近视眼患者12例(23只眼),分别在术前、术后1、3、6个月采用CS测试灯箱(CSV-1000型,美国Vector Vision公司)检查暗视状态下无/有眩光时的对比敏感度函数(contrast sensitivity function,CSF)。结果 术后1、3、6个月等效球镜度数分别为(-0.60±0.77)D,(-0.48±0.77)D,(-0.34±0.53)D,与术前(-15.53D±3.65D)差异均有显著统计学意义(P均〈0.001),最佳矫正视力(IogMAR)分别为0.064-0.12,0.02±0.09,-0.003±0.08,与术前(0.21±0.12)差异均有显著统计学意义(P均〈0.001)。术后各空间频率的CS与术前比较有增高趋势。术后3个月6、12、18周/度的CS在无眩光时和有眩光时均明显提高(P均〈0.01),开始接近正常范围。术后3、6个月在各空间频率上CS差异均无统计学意义(P均〉0.05)。结论 ICPIOL植入术矫治高度近视眼可以使CSF恢复到接近正常范围,显著改善视功能,是一种适用于高度乃至超高度近视眼的可供选择的屈光手术。  相似文献   
57.
58.
左氧氟沙星治疗细菌性感染70例   总被引:40,自引:2,他引:38  
目的:观察左氧氟沙星治疗细菌感染的疗效和安全性。方法:以左氧氟沙星治疗细菌性感染70例(男性35例,女性35例,年龄54±s15a),其中下呼吸道感染40例,尿路感染30例,剂量一般为0.2g,po,bid,疗程7~14d;单纯性下尿路感染为0.2g,po,qd,疗程5~7d。结果:总有效率93%,细菌清除率88%,不良反应轻微,呈一过性,发生率为6%。结论:左氧氟沙星治疗细菌性感染有效而安全。  相似文献   
59.
In order to evaluate the possibility of finding persons whohave suffered a myocardial infarction (MI) by postal questionnaire,a self-administered questionnaire was sent to a random sampleof 4400 men aged 45–64 years, drawn from the general population.The response rate was 95%. 176 men indicated that they had beenhospitalized for MI, out of which 124 cases could be verifiedfrom medical records. Of the remaining men, 33 had evidenceof cardiovascular disease (CVD) in their records but no MI,and 19 men had no evidence of CVD. The sensitivity (estimatedfrom a subsample) was 100% and the specificity 98.7%. The predictivevalue was 100% for a negative response and 70.5% for a positiveresponse. The 33 positive responders whose MI could not be verified butwho had evidence of CVD had characteristics fairly similar tothe responders with verified Mis. However, the 19 positive responderswhose MI could not be verified and who had no evidence of CVDhad characteristics that were dissimilar from the MI group aswell as from the negative responders. The questionnaire thus identified all the MI cases. The needfor validation can be limited to the relatively small groupof positive responders.  相似文献   
60.
A 10-year-old Persian girl has symptoms of congenital stationary night blindness and some drusen-like lesions in the region of the vascular arcades. Her electroretinogram shows no rod response to a weak stimulus, but a large (475 V) slow scotopic response to a strong stimulus that is unchanged by photopic conditions (15 F1 background illumination). However, the response to flicker had the typical (smaller) amplitude of a cone signal. This may represent a new form of night blindness in which rod sensitivity is reduced so that there is no vision under dim conditions but rod function still persists under photopic conditions.  相似文献   
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