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21.
Abstract Nitric oxide (NO) plays an important physiological role in regulating gastrointestinal motility. Involvement of endogenous NO was evaluated in the response to non-adrenergic, non-cholinergic (NANC) nerve stimulation of the dog sphincter muscle of Oddi. Transmural electrical stimulation (TES), nicotine (10?5M) and K+ (10 mM) produced only a relaxation in the sphincter muscle strips contracted with substance P, which was not potentiated by atropine. The TES-induced relaxation was abolished by tetrodotoxin (3 times 10?7 M) and oxyhaemoglobin (1.6 times 10?5 M), but not affected by atropine (10?7 M), propranolol (10?7 M), phentolamine (10?7 M), indomethacin (10?6 M), chole-cystokinin (CCK, 10?8 M) and vasoactive intestinal polypeptide (VIP, 10?8 M). The relaxation was also abolished by treatment with NG-nitro-L-arginine (L-NA, 10?5 M), an NO synthase inhibitor. Nicotine produced a transient relaxation, which was abolished by tetrodotoxin, hexamethonium (10?5 M) and L-NA, but not affected by atropine and NG-nitro-D-arginine (D-NA, 10?5 M). The addition of K+ elicited a transient relaxation, which was abolished by tetrodotoxin and L-NA. The inhibitory effects of L-NA were antagonized by L-arginine (10?3 M). The presence of neurons containing nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase was histochemically demonstrated in the sphincter of Oddi. These findings may indicate that TES, nicotine and K+ liberate NO from NANC inhibitory nerve which is involved in the relaxation of the dog sphincter of Oddi. The muscular tone does not seem to be regulated by cholinergic nerves under the experimental conditions used. 相似文献
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Stuart M. Lichtman Abraham Mittelman Daniel R. Budman Carmelo A. Puccio Hoo G. Chun Steven L. Allen Tauseef Ahmed Zalmen A. Arlin 《Leukemia & lymphoma》1991,6(1):61-63
A phase II trial of fludarabine phosphate using a bolus and continuous infusion regimen in previously treated multiple myeloma was performed. No responses were observed in eleven patients. There was no significant non-hematologic toxicity noted. Fludarabine phosphate is inactive in multiple myeloma using this schedule. 相似文献
24.
对TOCP染毒母鸡进行为期7周的神经电生理监测,结果表明,TOCP主要影响远端周围神经,导致坐骨神经远端MCV和SCV减慢及腓肠肌EMG失神经样改变,而胫后神经H反射及重复电刺激无明显异常。 相似文献
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载银磷酸锆纱布对烧伤创面常见细菌作用的实验研究 总被引:1,自引:1,他引:0
目的 了解载银磷酸锆纱布对烧伤大鼠创面感染常见细菌的抗菌效力。方法制作Wistar大鼠烫伤(以下称烧伤)感染模型,采用试管双倍稀释法测定载银磷酸锆及磺胺嘧啶银的最低抑菌浓度(MIC)及最低杀菌浓度(MBC)。观察大鼠创面用磺胺嘧啶银纱布、普通尢菌纱布、载银磷酸锆纱布(小水洗及水洗20次)后痂下组织的细菌计数和对创面愈合的作用。结果载银磷酸锆对金黄色葡萄球菌、铜绿假单胞菌、大肠竹菌的MIC各为8、8、16mg/L,MBC各为16、8、32mg/L,为磺胺嘧啶银的2~8倍?大鼠创面用未水洗的载银磷酸锆纱布覆盖后,痂下细菌计数比用磺胺嘧啶银纱布低91%,比普通无菌纱布低99%未水洗的载银磷酸锆纱布对创面愈合的作用明显优于其他两种纱布,且其痂下组织细菌计数与水洗20次的效银磷酸锆纱布比较,差异无显著性意义(P>0.05)。结论载银磷酸锆埘烧伤创面感染常见细菌有较强的抑制和杀灭作用,其敷料可作为治疗措施中新的选择。 相似文献
27.
Alvarez-Arroyo M. V. Traba M. L. Rapado A. de la Piedra C. Torralbo M. 《Urological research》1992,20(1):96-97
Summary Different mechanisms could explain the elevated calcium elimination, the main cause of calcium oxalate renal stones. Our results suggest that phosphate levels are decreased in patients with absorptive hypercalciuric nephrolithiasis and elevated serum dihydroxyvitamin D. This could be the reason why in this group of patients oral phosphate treatment prevented hypercalciuria and renal lithiasis.This work was supported by FlSss 89/0799 相似文献
28.
Shane L. Carney Alastair H. B. Gillies Cheryl D. Ray 《Clinical and experimental pharmacology & physiology》1995,22(9):629-634
1. Despite human and animal studies, the direct effect of ethanol on renal water and electrolyte transport is poorly understood. The acute effect of increasing plasma concentrations of ethanol was evaluated in a water diuretic anaesthetized rat model which inhibits endogenous arginine vaso-pressin (AVP) release. 2. Ethanol at a plasma concentration of 1.69 ±0.28 mmol/L produced an immediate increase in urine flow (174 ± 11 μL/min pre-ethanol and 189 ± 13 and then 206 ± 12 μL/min during the ethanol infusion; P<0.001) as well as an increase in fractional sodium excretion (0.17 ± 0.04 to 0.28 ± 0.05 and 0.27 ± 0.05%; P<0.001). There was also a brief phosphaturia. These increases in electrolyte excretion had returned to control values by 20 min despite a further increase in the plasma ethanol concentration. 3. The urinary excretion of potassium, calcium and magnesium was not altered nor was glomerular filtration rate or renal plasma flow. 4. Ethanol at a mean concentration of 1.60 mmol/L did not alter the action of a maximal concentration of AVP (75 ng/kg) on water or electrolyte transport. However, the antidiuretic effect of a submaximal concentration of AVP (7.5 ng/kg) was augmented by ethanol at concentrations of 1.63 and 0.98 mmol/L. 5. These studies suggest that the ethanol induced diuresis commonly ascribed to inhibition of AVP secretion may also be due to other intrarenal effects of ethanol, possibly acting within the proximal tubule. These results also confirm recent in vitro findings that while ethanol does not inhibit the action of a maximal concentration of AVP, it does modulate the effects of lower AVP concentrations. 相似文献
29.
目的:应用磷酸镁骨水泥(magnesium phosphate cement,MPC)粘接固定家兔胫骨平台骨折,探讨其治疗效果、粘接和降解机理。方法:20只家兔分为两组,第1组15只,第2组5只,通过开放截骨法建立家兔双侧胫骨平台骨折模型。第1组:实验组用MPC骨水泥固定,对照组用“L”形钢板固定。第2组:实验组也同样用MPC骨水泥固定,而对照组作空白对照。通过大体观察、影像学、组织学及电解质检查,探讨MPC骨水泥治疗骨折的效果、对体内电解质的影响、粘接和降解机理。结果:6周后实验组都获得稳定的骨折愈合,没有发现骨折错位及延迟愈合,MPC骨水泥逐渐被吸收,对体内电解质无明显影响,其对骨折的治疗和钢板固定组达到同样的治疗效果。而空白对照侧均出现骨折错位、畸形愈合。通过对标本的组织学检查发现其粘接机理为镶嵌固定,并通过溶解而逐步降解。结论:MPC骨水泥具有一定的粘接强度,能降解,对体内电解质干扰小,是一种较为理想的骨水泥,可以用于骨折的粘接固定。 相似文献
30.
Distal radial fractures Injectable calcium phosphate bone cement versus conventional treatment 总被引:2,自引:0,他引:2
AMEDLINEsearchwasconductedtoidentifystudiespublishedfromJanuary1999toMarch2004thatcom-paredinjectablecalciumphosphatebone(NorianSRS)cementwithconventionaltreatmentindistalradialfrac-tures.Fromalistof13articlesidentifiedfromthesearchstrategy,fourarticleswe… 相似文献