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991.
992.
Maria G. Matera Mario Cazzola Maria Constantino Dante De Santis Francesco Rossi 《Clinical and experimental pharmacology & physiology》1992,19(9):627-630
1. Airways derived from different levels of the lung exhibit a difference in the reactivity and sensitivity to agonists. We have evaluated the effect of acetylcholine and cholinergic selective (pirenzepine, gallamine and 4-dipherylacetoxymethyl piperidine [4-DAMP]) and non-selective (atropine) antagonists on bovine proximal and distal smooth muscle preparations. 2. The distal preparations are more sensitive to acetylcholine than proximal bronchi. The relaxant effect of three selective antagonists on the distal and proximal tissues was the same when the results for each drug were compared. 3. Atropine and 4-DAMP were more potent than pirenzepine and gallamine in relaxing both proximal and distal bovine smooth muscle preparations. 4. These data suggest that the muscarinic sites on the smooth muscle of bovine airways are of the M3 subtype. 相似文献
993.
以超微结构、线粒体形态计量及LDH,SOD活性为依据,探讨3,4-二羟基苯乙酮(DHAP)对家兔缺血-再灌心肌细胞的影响。结果表明:DHAP组缺血-再灌心肌细胞的损伤、LDH丢失及SOD活性下降的程度均明显低于未用药组。提示该药物对缺血-再灌心肌有保护作用。 相似文献
994.
R Vettor C Martini L Calò S Cantaro C Macor C De Palo N Sicolo C Scandellari G Federspil 《Diabète & métabolisme》1992,18(3):213-217
Anomalies in prostaglandin (PG) synthesis have been suggested in both experimental and human diabetes mellitus; increased levels of plasma and tissue eicosanoids has been recently reported by several investigators. One step in prostaglandin synthesis is the enzymatic hydrolysis of membrane phospholipids by Phospholipase A2 (PLA2). Nevertheless the alternative pathway involving Phospholipase C must be considered. An evaluation of PLA2 activity is therefore a useful method for studying prostaglandin synthesis in the peripheral target tissues of insulin activity. We studied PLA2 activity in normal and diabetic rat muscle. Streptozotocin-induced diabetic rats showed significantly higher muscular PLA2 activity when compared with controls (3.04 x 10(-2) +/- 0.50 x 10(-2) versus 1.34 x 10(-2) +/- 0.35 x 10(-2) arachidonic acid pMol.mg protein-1.min-1 (p less than 0.01). This effect was not observed in diabetic animals successfully treated with insulin (1.78 x 10(-2) +/- 0.5 x 10(-2) versus 1.34 x 10(-2) +/- 0.35 x 10(-2) arachidonic acid pMol.mg protein-1.min-1), and a significant correlation was found between blood glucose and muscular PLA2 activity (r = 0.42; p less than 0.05). Our results clearly show that in streptozotocin-induced diabetic rats muscular PLA2 activity is significantly higher. The relationship between blood glucose levels and muscular PLA2 activity and the decrease of PLA2 activity after insulin treatment suggest that these changes may be related to a defect in insulin effect. 相似文献
995.
Dr. A. Belluzzi MD C. Brignola MD M. Campieri MD E. P. Camporesi BS P. Gionchetti MD F. Rizzello MD C. Belloli MD G. De Simone MD S. Boschi MD M. Miglioli MD L. Barbara MD 《Digestive diseases and sciences》1994,39(12):2589-2594
Fish oil has been recently proposed as a possible effective treatment in inflammatory bowel disease (IBD); however, a lot of annoying side effects (ie, belching, halitosis, diarrhea, etc) affect patient compliance. We carried out a study of patient tolerance in a group of Crohn's disease (CD) patients with a new fish oil derivative consisting of 500-mg capsules of eicosapentaenoic-docosahexaenoic (EPA 40%-DHA 20%), a free fatty acid mixture (Purepa), and we also evaluated its incorporation into phospholipids, both in plasma and in red cell membranes. Five groups of 10 CD patients in remission received nine Purepa capsules daily in four different preparations (A: uncoated, B: coated, pH 5.5; C: coated, pH 5.5, 60 min time release; D: coated, pH 6.9) and 12 × 1-g capsules daily of a triglyceride preparation (Max-EPA, EPA 18%-DHA 10%), respectively. We coated three of the four Purepa preparations in order to delay the release of contents in an attempt to minimize the side effects. After six weeks of treatment, the group taking Purepa capsules, coated, pH 5.5, 60 min time release (group C) showed the best incorporation of EPA and DHA in red blood cell phospholipid membranes (EPA from 0.2 to 4.4%, DHA from 3.7 to 6.3%), and no side effects were registered, whereas in all other groups side effects were experienced in 50% or more of subjects. This new preparation will make it possible to treat patients for long periods. 相似文献
996.
目的 评价国产流行性感冒(简称流感)病毒裂解疫苗的安全性和免疫效果.方法 选择6岁~、16岁~和>60岁3个年龄段人群共606名,每个年龄段人群按数字表法随机分入试验组(共213名)、对照组1(共195名)和对照组2(共198名),分别接种国产流感疫苗和2种进口流感疫苗,比较三组人群接种后副反应发牛率、抗体阳转率、保护率及几何平均滴度(GMT)增长倍数的差异.率的比较采用X2检验,几何平均滴度(GMT)增长倍数采用方差分析,P<0.05为差异有统计学意义.结果 试验组、对照组1、对照组2副反应发生率分别为3.76%(8/213)、4.10%(8/195)和3.54%(7/198),差异无统计学意义(X2=0.87,P=0.93).3个组H1N1、H3N2和B(亚)型血凝抑制(H1)抗体总阳转率分别为89.2%(190/213)、63.4%(135/213)、86.4%(184/213),88.7%(173/195)、61.5%(120/195)、87.2%(170/195),87.9%(174/198)、61.6%(122/198)、84.8%(168/198),各(亚)型抗体总阳转率差异无统计学意义(X2H1N1=0.94,PH1N1=0.63;X2H1N2=0.94,PH3N2=0.63;X2B=0.75,PB=0.69);3个组H1N1、H3N2及B型H1抗体平均增长倍数分别为10.7、7.3、8.4倍,10.5、6.3、8.3倍,10.2、7.1、8.8倍,各(亚)型H1抗体GMT增长倍数差异无统计学意义(FH1N1=0.35,PH1N1=0.70;FH3N2=2.22,PH3N2=0.11;FB=1.51,PB=0.35);3个组H1N1、H3N2及B型H1抗体保护率分别为100%(213/213)、70.0%(149/213)、95.3%(203/213),100%(195/195)、66.7%(130/195)、97.9%(191/195),99.5%(197/198)、66.2%(131/198)、96.5%(191/198),各(亚)型抗体保护率差异无统计学意义(X2H1N1=2.04,PH1N1=0.36;X2H3N2=0.74,PH3N2=0.69;X2B=0.42,PB=0.82).结论 国产裂解流感疫苗具有良好的安全性和免疫效果,可用于群体性接种. 相似文献
997.
998.
前列腺素E1对大鼠肝脏缺血再灌注损伤的保护作用 总被引:2,自引:0,他引:2
目的 探讨前列腺素E1(PGE1)对肝脏 因再灌注损伤的保护作用。方法 制作常温下大鼠部分肝叶缺血再灌注模型,于缺血前经门静脉给予PGE1,45min后恢复血流灌注,并于1h后取门静脉血测定血清谷草转氨酶(GOT)、谷丙转氨酶(GPT)、乳酸脱氢酶(LDH)、肿瘤坏死因子-α(TNF-α)及内皮素1(ET-1),同时取缺血肝叶行病理组织学检查。结果 缺血再灌注组GOT、GPT、LDH及TNF-α和ET-1均明显高于正常对照组,PGE1组则明显低于缺血再灌注组。PGE1组的肝脏病理组织学改变明显轻于缺血再灌注组,并接近正常对照组。结论 PGE1对肝缺血再灌注具有保护作用。 相似文献
999.
Hypocalcemia after thyroidectomy. 总被引:7,自引:0,他引:7
N Demeester-Mirkine L Hooghe J Van Geertruyden V De Maertelaer 《Archives of surgery (Chicago, Ill. : 1960)》1992,127(7):854-858
Serum calcium, sodium, potassium, chloride, magnesium, phosphorus, osmolarity, total protein, albumin, parathyroid hormone, and calcitonin values were systematically surveyed in 135 patients who underwent thyroidectomy and in 104 control surgical patients. A transient and moderate hypocalcemia developed after operation in thyroidectomized and control patients. Concentrations of other electrolytes, osmolarity, proteins, and albumin followed the same pattern of evolution. After thyroidectomy, the degree and duration of hypocalcemia increased with the extent of thyroid resection. A profound hypocalcemia (less than 2.0 mmol/L) and a marked reduction of the parathyroid hormone concentration (below normal) were present in 12% and 8% of cases after subtotal thyroidectomy and in 22% after total thyroidectomy. Calcitonin values did not increase after thyroidectomy. A slight correlation was observed between the preoperative serum alkaline phosphatase level and the minimal postoperative serum calcium level. It is concluded that post-thyroidectomy hypocalcemia is a multifactorial phenomenon. It is due, at least in part, to hemodilution. A temporary parathyroid insufficiency after subtotal and total thyroidectomy, and an avidity of the skeleton for calcium in hyperthyroid patients, may aggravate the hypocalcemia. 相似文献
1000.
目的:测定妊高征患者血清睾酮水平并探讨其临床意义。方法:采用放射免疫分析法测定妊高征患者30例、正常孕妇20例血清及其新生儿脐血睾酮水平。结果:妊高征患者血清睾酮水平(0.153±0.078nmol/L)明显高于正常孕妇组(0.023±0.015nmol/L),有显著性差异(P<0.001)。妊高征组脐血睾酮水平(0.052±0.041nmol/L)低于正常孕妇组(0.119±0.059nmol/L),有显著性差异(P<0.05),两组睾酮水平与新生儿性别无关(P>0.05)。结论:孕妇血清睾酮在妊高征的病理生理中起调节或加强作用。 相似文献