蠕变局部损伤开裂的有限元模型

建立了蠕变局部损伤法模型,并给出单元进入损伤态的判据和失效的临界拉伸应变条件,局部蠕变损伤理论的实质就是试样是多种不同蠕变性能材料的统一,并由蠕变应力再分布得到证实,应用有限元对双缺口圆试样作了蠕变局部损伤分析,启裂时间和断裂蠕变应变值均与实验结果相吻合。     

Analysis of the factors influencing the therapeutic effects of onychomycosis

From July 1 994to June 1 999,5 4 5 onychomyco-sis patients were treated with Itraconazole and com-pleted their treatment courses with complete follow-up in out- patientdepartment.The recovery rate was83.1 4% and 79.2 3% in fingernail and toenail dis-eases respectively.But following phenomena werefound:( 1 ) Some new nails stopped growing in cer-tain length,even if the treatment continued;( 2 )Some damaged nails reappeared soon after the treat-ment ceased;( 3) Some damaged nails with deep- co…     

一氧化氮对犬下食管括约肌压力的作用

目的 :应用苄基二甲基十四烷氯化铵 (benzyldim ethyltetradecyl amm onium chloride,BAC)建立犬下食管括约肌(L ES)无神经动物模型 ,研究一氧化氮 (NO)对 L ES压力的作用。方法 :将 BAC环周注入犬 L ES,对照组注入等量生理盐水 ,均于注射前及注射后 6周测定 L ES压力 ;并观察 L -精氨酸、D -精氨酸、硝普钠及一氧化氮合酶 (NOS)抑制剂 N-硝基 - L -精氨酸 (L - NNA)对 L ES压力的影响 ;此外还测定了两组犬 L ES中 NO含量和 NOS活性。结果 :BAC处理组 L ES压力 [(4 2 .43±4.19) m m Hg,1m m Hg=0 .133 k Pa]显著高于对照组 [(2 2 .71± 5 .19) mm Hg]。 L -精氨酸可使对照组 L ES压力降低 ;L - NNA使其增高 ,但对 BAC处理组 L ES压力均无影响。硝普钠可降低两组犬 L ES压力。对照组 L ES中 NO为 (6 .0 5 8± 2 .0 6 7)μm ol/g,NOS为 (1.45 8± 0 .146 ) U /mg;而 BAC处理组 NO为 (1.797± 0 .873)μmol/g,NOS为 (0 .46 3± 0 .0 39) U /m g,均较对照组显著降低 (P<0 .0 1)。 结论 :BAC可使犬 L ES压力增高 ,其机制可能与 L ES局部 NO减少有关。     

家兔急性实验性面神经损伤的组织病理观察

目的　观察家兔面神经急性损伤后髓鞘和轴索的组织病理变化。方法　用丝线结扎茎乳孔以外的面神经总干 ,观察结扎后 1天、3天及 5天面神经的组织病理改变。结果　家兔面神经受损后 ,先后在髓鞘和轴索出现轻重不等、程度不同的形态学改变。结论　结扎家兔面神经后 ,其髓鞘及轴索会出现相应的病理改变 ,且随着结扎天数的增加 ,面神经损伤亦呈加重的趋势     

Probucol improves erectile function by regulating endoplasmic reticulum stress in rats with streptozotocin-induced diabetes

This study was to explore the effect and mechanism of Probucol on STZ-induced erectile dysfunction in diabetic rats. Thirty SD male rats aged 12 weeks were given intraperitoneal injection of STZ after fasting for 12 hr. Diabetic rats were haphazardly partitioned under two assemblies and administered 0 or 500 mg/kg probucol by oral gavage to 12 weeks. Control group was intraperitoneally injected with physiological saline, and saline was administered by oral gavage daily. Intracorporeal pressure was used to evaluate erectile function. Levels of proteins were detected using immunohistochemistry and Western blotting. α-SMA and vWF were detected using immunofluorescence staining. After treatment, erectile function in probucol group was significantly improved. Endoplasmic reticulum stress-related proteins were expressed higher in DM group than in sham group, while expression of these proteins decreased significantly in probucol group. However, α-SMA and vWF were expressed at lower levels in DM group than in sham group, and probucol treatment reversed this phenomenon. Finally, Bax and Caspase3 were expressed at higher levels and Bcl-2 was expressed at lower levels in DM group, while the opposite result was obtained in probucol group. In conclusions, probucol improves erectile function by reducing endothelial dysfunction and inhibiting PERK/ATF4/CHOP pathway in STZ-induced diabetic rats.     

Safety and efficacy of thulium laser resection of bladder tumors versus transurethral resection of bladder tumors: a systematic review and meta-analysis

Lasers in Medical Science - The thulium laser resection of bladder tumor (TmLRBT) is widely used in the treatment of non-muscle-invasive bladder cancer (NMIBC), and we conduct this study to compare...