Negative inotropic effect of 3,6-dimethamidodibenzopyriodonium citrate (I-65) on guinea pig papillary muscles

The effects of 3,6-dimethamidodibenzopyriodonium citrate (I-65) on the contractile response of electrically paced guinea pig papillary muscles in vitro were studied. I-65 (0.1-300 mumol/L) decreased the contractile force and inhibited isoprenaline-induced restoration of the contractile response in papillary muscles rendered inexcitable by KCl 22 mmol/L. Both effects were concentration-dependent, and the IC50 were 36.0 and 7.3 mumol/L, respectively. I-65 antagonized the positive inotropic effects of Iso and CaCl2 in a non-competitive manner. Like verapamil, I-65 had a frequency-dependent negative inotropic effect, and delayed the recovery of post-rest potentiation. It is concluded that the negative inotropic effect of I-65 results not only from the reduction of Ca2+-influx through the sarcolemmal membrane, but also from the inhibition of Ca2+ translocation in the sarcoplasmic reticulum.     

Effectiveness of montelukast in the treatment of cough variant asthma.

BACKGROUND: Antileukotriene agents have been shown to be beneficial in chronic asthma. Although patients with cough variant asthma have cough with minimal wheezing and dyspnea, airway hyperresponsiveness from chronic inflammation is believed to be the underlying mechanism. OBJECTIVE: To evaluate the effectiveness of montelukast, a leukotriene receptor antagonist, in the treatment of cough variant asthma. METHODS: Fourteen patients with cough variant asthma participated in a randomized, double-blind, placebo-controlled trial with a 7- to 10-day baseline period and a 4-week treatment period with montelukast, 10 mg, or placebo daily. Inclusion criteria were (1) chronic cough with a duration of at least 4 weeks with minimal or no wheezing or dyspnea and (2) forced expiratory volume in 1 second of 50% to 85% of predicted and reversibility of 12% with use of an inhaled beta-agonist or forced expiratory volume in 1 second greater than 85% and positive methacholine challenge results. Patients fulfilled the minimum criteria for cough frequency and symptom scores for randomization. RESULTS: Eight patients received montelukast and 6 received placebo. The primary efficacy variable, mean percentage change from baseline in cough frequency, was significantly improved by the second week, and by the fourth week the mean percentage change from baseline was 75.7% for the treatment group and 20.7% for the placebo group. CONCLUSIONS: The leukotriene receptor antagonist montelukast seems to be effective in the treatment of cough variant asthma. Larger studies are recommended to confirm this effect.     

喉癌组织T淋巴细胞亚群与外周血前列环素及血栓素的检测

目的 探讨喉癌局部组织的细胞免疫状态与前列腺素类物质前列环素及血栓素的关系。方法 应用免疫组化法检测了28例喉鳞癌患者局部组织内淋巴细胞亚群的分布状况，并与该患者残喉健康侧组织及喉良性肿瘤患者的瘤组织进行对比；同时采用放射免疫分析法分别检测了上述喉鳞癌、喉良性肿瘤患者和正常人血浆前列环素(PGI2)及血栓素A2(TXA2)的含量，并以它们在健康人血浆中的含量为正常对照。结果 喉癌组织内浸润的CD4和CD8细胞数明显升高，而且CD8细胞多于CD4细胞，提示喉癌组织局部的细胞免疫功能受抑。同时喉癌患者血浆中PGI2和TXA2的稳定代谢产物6-酮-前列腺素F1α及血栓素B2(TXB2)的含量高于正常对照组，以TXB2升高更明显。结论 喉癌患者体内前列腺素类物质PGI2／TXA2与其癌组织局部细胞免疫受抑有关，因而可作为生物学标记提示喉癌组织局部的细胞免疫功能状态。     

谈耳鼻喉科教学中多媒体技术的应用

多媒体教学技术应用于耳鼻喉科教学,具有直观性好、动态感强、信息量大等优点,能使教学信息直接、形象、具体、生动地展现给学生,让学生体会到学习的乐趣,是耳鼻喉科现代化教学的理想模式.     

消化道手术中医源性脾损伤的预防和处理

医源性脾损伤(iatrogenicsplenicinjury)通常是指处理脾脏邻近器官的手术时,由于手术操作、医疗器械使用不当或局部解剖变异所造成的脾脏损伤。在临床上因各种原因导致的医源性脾损伤并不罕见,而且一旦发生损伤将会引发手术时间延长、术中失血量增加、病人住院时间延长等一系列问题;有的尚须行无辜性脾切除,导致脾切除术后发生并发症的风险增加,不仅给病人带来痛苦,甚至危及其生命。因此,医源性脾损伤已成为外科领域值得关注的问题。1应尽力避免医源性脾损伤消化道手术中医源性脾损伤的发病情况国内外报道不尽相同。Cassar等[1]报告,近40%…     

大鼠骨髓间充质干细胞转染人TH基因的实验研究

目的评价酪氨酸羟化酶(tyrosine hydroxylase,TH)基因修饰骨髓间充质干细胞(mesenchymalstem cells,MSCs)后TH的表达情况及转染TH基因对MSCs的影响.方法构建含人TH基因的pCMV/hTH质粒,用脂质体转染原代培养的大鼠MSCs;Western blot及免疫细胞化学染色鉴定TH基因的表达及MSCs的分化情况;MTT比色法测定转染后的MSCs细胞活性,并与未转染的MSCs进行细胞活性比较.结果构建的pCMV/hTH质粒经ECoRI酶切后产生1.9okb和5.3kb的片段,与回收的目的基因及载体基因片段大小相符;转基因后的MSCs Western blot及免疫细胞化学染色显示TH染色阳性;转染后MSCs未见有NeuN,GFAP的表达;MTT比色法测定细胞活性,未转染与转染者差异无显著性.结论构建的TH基因能在体外培养的鼠MSCs中较好的表达,转染不会诱导MSCs向神经样细胞分化,对MSCs细胞活性无明显影响.     

急性缺血性脑血管疾病的药物序贯治疗

目的:探讨药物的序贯治疗对急性缺血性脑血管病的治疗效果。方法:随机分成去纤酶、奥扎格雷钠、盐酸丁格地尔序贯治疗组和使用肠溶阿斯匹林、复方丹参针对照组,治疗组和对照组在治疗前后作神经功能评估,患者的生活能力状态评价及脑循环血流变化的测定。结果:治疗组显效率76.1%,有效率8.7%,总有效率84.8%,对照组显效率23.5%,有效率14.7%,总有效率38.2%(P<0.05)。结论:药物序贯治疗急性缺血性脑血管病比常规治疗疗效显著。     

~3H-α-第二丁基对羟基苄醇在家兔体内的药物动力学研究

本文报道给家兔注入不同剂量的~3H-α-第二丁基对羟基苄醇,观察该药在其体内的药物动力学。结果表明,血中分布相快,消除相慢,消除半衰期T_1/1β为12h。经F值检验和理论计算值与实测值的契合程度比较,表明该药在兔体内的运转符合二室开放模型的动力学方程。     

Effects of diet-induced ketosis in rats with hypoglycaemia due to a serially transplantable insulinoma

In view of the ability of ketones to partially replace glucose as an alternative fuel in the brain, the potential protective effects of diet-induced ketosis were examined in male NEDH rats with hypoglycaemia due to a serially transplantable radiation-induced insulinoma. Ketosis was induced by daily oral administration of medium chain triglycerides to normal rats and to insulinoma-bearing rats 1 day after subcutaneous subscapular implantation of tumours fragments. All rats treated with medium chain triglycerides became ketotic within 72 hours, and plasma 3-hydroxybutyrate concentrations remained 5-10 fold elevated at 24 days. Untreated insulinoma-bearing rats became moderately hyperinsuliaemic and hypoglycaemic by 17 days, with the later manifestation of more marked hyperinsulineamia (21.6 +/- 0.8 ng/ml, mean +/- SEM) severe hypoglycaemia (1.5 +/- 0.1 mmol/l) and death by 24-28 (26 +/- 1) days. Induction and maintenance of hyperketonaemia did not affect the development of hyperinsulineamia, hypoglycaemia or the exaggerated fall of plasma glucose produced by an 8 hour fast in these rats. However by day 21, the severity of hypoglycaemia was greater in insulinoma-bearing rats receiving medium chain triglycerides, culminating in accelerated death by 22-25 (23 +/- 1) days and an accompanying 50% decrease in final tumour weight. These results demonstrate that induction of ketosis in the face of marked hyperinsulinaemia did not afford protection against the profound hypoglycaemia produced by a serially transplantable rat insulinoma.