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排序方式: 共有1023条查询结果,搜索用时 12 毫秒
1.
本文报道一种广谱、高效且有一定洗涤作用的杀菌抗病毒溶液——DF-88消毒洗涤剂,对其杀灭常见细菌和灭活乙肝病毒的效果及其稳定性、毒性作用等进行了初步观察。结果表明,当有效碘含量为2.54mg时,能完全杀死常见细菌;有效碘含量为23mg时,可有效地灭活乙肝病毒。此外,其LD_(50)为487mg/kg,皮肤刺激试验无任何充血、红斑等改变。  相似文献   
2.
This study was undertaken to determine if PG490-88 and tacrolimus (Tac) act synergistically to prevent renal allograft rejection in monkeys and to explore possible mechanisms of synergy between these agents. MHC-mismatched renal allografts were transplanted into cynomolgus monkeys after bilateral nephrectomy. Recipients were divided into the following groups: (i) no treatment; (ii) PG490-88 (0.03 mg/kg); (iii) Tac (1 mg/kg); (iv) PG490-88 (0.01 mg/kg) + Tac (1 mg/kg) and (v) PG490-88 (0.03 mg/kg) + Tac (1 mg/kg). Through synergy PG490-88 and Tac inhibited anti-CD3/PMA-induced T-cell proliferation and IFN-gamma expression in vitro. Tac monotherapy only marginally prolonged survival (27 +/- 3.2 days), while the combination of PG490-88 and Tac significantly prolonged graft survival to a median of 99 days (PG490-88 at 0.03 mg) and 38.5 days (PG490-88 at 0.01 mg/kg). Prolonged survival correlated with inhibited IgM production as well as reduced T-cell infiltration, IL-2 protein expression and NF-AT/NF-kappaB activity. We conclude that PG490-88 and a subtherapeutic dose of Tac significantly prolong renal allograft survival in monkeys through the synergistic inhibition of T-cell activation and a decrease in IFN-gamma production and NF-AT/NF-kappaB activity.  相似文献   
3.
Testosterone, administered in the form of an inclusion complex with 2-hydroxypropyl--cyclodextrin by subcutaneous injection, enters the circulation in a manner markedly similar to the natural episodic release by the testes. The effects of a regimen of once-a-day administration of complexed testosterone to adult (castrated or intact) rats and to senescent (intact) rats were investigated. Although this procedure left the castrated animals with concentrations of circulatory hormone far below physiological levels for much of the day, a significant improvement in androgen-sensitive behavior and physiology was obtained. Furthermore, the testosterone effects were more pronounced when high doses were used periodically rather than when the same total amount of testosterone was equally divided among doses. The same supplementation to intact rats intensified androgen-sensitive behavior and physiology over normal levels. In senescent rats uniform pulses of the testosterone complex also improved behavior and physiology. Specifically, spermatogenesis was stimulated and, notably, the treatment increased muscle weight without substantial enlargement of the prostate. Since the testosterone–cyclodextrin complex also can be effectively administered as a sublingual tablet, the data suggest that similar regimens may be recommended for elderly men suffering from decreases in muscle mass.  相似文献   
4.
目的:探究桃红四物汤对糖尿病周围神经病变(DPN)大鼠炎症反应及对Toll样受体4(TLR4)/髓样分化因子88(MyD88)/核转录因子kappan B(NF-κB)通路的影响。方法:从45只SD大鼠中随机选取10只为对照组,其余35只大鼠建立DPN模型,3只大鼠建模失败,其余随机分为模型组,桃红四物汤低、高剂量组及α-硫辛酸组,每组各8只。桃红四物汤低、高剂量组分别给予4.5、18 g/(kg·d)的桃红四物汤,α-硫辛酸组给予α-硫辛酸20 mg/(kg·d),对照组及模型组给予等量的0.9%氯化钠溶液,均灌胃给药。连续给药8周后,检测大鼠血清炎症因子、血糖及血脂指标及神经传导情况,观察坐骨神经病理学变化,检测TLR4相关通路蛋白表达情况。结果:与对照组比较,模型组血清肿瘤坏死因子-α(TNF-α)、白细胞介素-1β(IL-1β)及白细胞介素-6(IL-6)水平升高,血糖、糖化血红蛋白(HbA1c)、甘油三酯(TG)及血清总胆固醇(TC)水平升高,感觉神经传导速度(SNCV)及运动神经传导速度(MNCV)水平降低,TLR4、MyD88、NF-κB蛋白表达上调(P<0.05)...  相似文献   
5.
Young semi-domesticated pigeons captured or hatched from eggs gathered in Bratislava during 1989–1991 were examined for complement fixing antibodies to Chlamydia psittaci and agglutinating antibodies to Coxiella burnetii. Antibodies to Ch. psittaci were present in 76% of birds younger than 24 h, in 47.7% between 1 and 10 days of age and in 12% of nestlings over 10 days old. Antibodies to Ch. psittaci were also detected in crop milk of 4.1% of 1 to 10 day old birds and in 4.5% of specimens older than 10 days. Antibodies to C. burnetii were not found in juvenile birds under 24 h old, but antibodies against this agent were present in 16.4% birds between 1 and 10 days old and in 18% over 10 days old. Antibodies to C. burnetii were also detected in crop milk collected from crops of 2% of the young birds between 1 and 10 days.  相似文献   
6.
目的:探讨木犀草素通过Toll样受体(Toll-like receptors,TLR)/髓样分化因子(myeloid differentiation factor 88, MyD88)/核因子κB(nuclear factor kappa-B,NF-κB)通路减轻急性痛风性关节大鼠炎症的作用及其机制。方法: 将60 只雄性Wistar 大鼠随机分为5 组:正常对照组、尿酸钠(monosodium urate,MSU)组、秋水仙碱组、木犀草素低剂量 组(50 mg/kg)、木犀草素高剂量组(150 mg/kg)。于大鼠踝关节局部注射尿酸钠晶体混悬液制备急性痛风性关节炎模 型,观察各组大鼠不同时间点的关节肿胀指数,并测定各组大鼠血清及滑膜中白细胞介素1β (interleukin-1β,IL-1β)、 白细胞介素6(interleukin-6,IL-6)、肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)的水平,采用实时PCR检测滑膜 组织中TLR2,TLR4,MyD88 mRNA 水平,蛋白质印迹测定滑膜组织中TLR2,TLR4,MyD88,磷酸化核因子 κBp65(phosphorylated-nuclear factor κB,p-NF-κB p65)蛋白表达,HE染色观察踝关节及其周围软组织炎症细胞情况, 免疫组织化学法测定NF-κB表达。结果: 与MSU组相比,木犀草素高、低剂量组及秋水仙碱组的关节肿胀指数均明 显降低(P<0.05),IL-1β,IL-6,TNF-α 的水平也显著降低(P<0.01),TLR2,TLR4,MyD88 mRNA和蛋白水平及NF- κB的蛋白水平均显著降低(P<0.01)。免疫组织化学结果显示:与正常对照组比较,木犀草素和秋水仙碱组大鼠踝关 节的炎症细胞明显减少,滑膜增生减少,软骨表面光滑,无明显软骨和骨侵蚀。结论: 木犀草素可通过下调TLR/ MyD88/NF-κB通路减轻急性痛风性关节炎的炎症反应,有望成为治疗急性痛风性关节炎的有效药物。  相似文献   
7.
447C88 (N-Heptyl-N-(2,4 difluoro-4-6-(2(-4-(2,2 dimethylpropyl)phenyl)ethyl)phenyl)urea) is an inhibitor of human microsomal AcylCoA:Cholesterol acyltransferase (ACAT) with an IC50 of 10.2 ng·ml–1 (23 nM). It is poorly absorbed but 5 mg·kg–1·day–1 completely abolishes the rise in plasma cholesterol in cholesterol-fed rats.In this study, twelve healthy, male volunteers received single, oral doses of 25, 50, 100, 200, 400 and 800 mg of 447C88 (n+8) or placebo (n+4) with food in a double-blind study with at least a week between occasions. The 400 mg dose was repeated after an overnight fast. Subsequently, fourteen different volunteers received a single 200 mg dose of 447C88 (n+8) or placebo (n+6) with food and, a week later, the same dose twice daily for 10 days; all doses were given with food.All doses were well tolerated with no significant changes in vital signs, full blood counts or plasma biochemical profiles. Plasma concentrations of 447C88 were unquantifiable after the fasting dose and low after all other doses. Mean Cmax and AUC were 1.8 ng·ml–1 and 9.0 ng·ml–1·h after 200 mg rising to 5.4 ng·ml–1 and 23.8 ng·ml–1·h respectively after 800 mg; t1/2 was 1.3 to 5.2 h. After 10 days dosing, plasma 447C88 concentrations were higher in the evening than the morning probably due to administration of the evening dose with more food. There were no significant changes in plasma triglcerides or total, LDL- or HDL-cholesterol after dosing with 447C88.  相似文献   
8.
Summary The coagulation cascade has a potential role in brain edema formation due to intracerebral hemorrhage. In this study blood and other solutions were injected stereotactically into the right basal ganglia in rats. Twenty-four hours following injection, brain water and ion contents were measured to determine the amount of brain edema. Intracerebral blood resulted in an increase in brain water content. The amount of brain edema surrounding the intracerebral hematoma was reduced by a thrombin inhibitor Na-(2-Naphthalenesulfonylglycyl)-4-amidino-DL-phenylalaninepiperidide, (-NAPAP) infused into the hematoma after the clot had been allowed to solidify. The inhibitor did not alter the actual size of the clot mass. An artificial clot composed of fibrinogen, thrombin, and styrene microspheres also produced brain edema. A fibrin clot led to edema formation even in the absence of mass effect provided by the microspheres. The single component responsible for production of brain edema in all these models was thrombin. The edema was formed in response to a fibrinogen-independent pathway. These results indicate that the coagulation cascade is involved in brain edema that develops adjacent to an intracerebral hematoma.  相似文献   
9.
Summary The aim of the present investigation was to examine whether or not presynaptic facilitatory -adrenoceptors are detectable on the postganglionic nerves in the rabbit isolated ear artery. Strips of rabbit central ear artery were incubated with 3H-noradrenaline (10–7 mol/l; 30 min or 10–6 mol/l; 60 min). Subsequently, they were washed repeatedly with physiological salt solution. The strips were subjected to electrical-field stimulation (S1–S8) and the resultant 3H-overflow was determined.When the ear artery was stimulated with 150 pulses (0.5 ms; 3 Hz; 225 mA), isoprenaline (10–9–10–6 mol/l) either alone or in the presence of either rauwolscine (10–6 mol/l) or phentolamine (10–6 mol/l) did not alter the stimulation-evoked 3H-overflow. This was also the case in the presence of rauwolscine (10–6 mol/l) plus either the selective phosphodiesterase inhibitor ICI 63 197 (3 × 10–5 mol/l) or forskolin (10–6 mol/l). When the ear artery was stimulated with 300 pulses (1 ms; 5 Hz; 225 mA), isoprenaline had no effect on the stimulation-evoked 3H-overflow. This was also the case when phentolamine (10–6 mol/l) was present. Propranolol (10–7–10–5 mol/l) did not alter the stimulation-evoked 3H-overflow. In some experiments, the stimulation current was reduced to 175 mA in order to obtain similar reference release (S3) values despite the presence of rauwolscine (150 pulses; 0.5 ms; 3 Hz). Even then, isoprenaline (10–9–10–6 mol/l) did not change stimulation-evoked 3H-overflow. The results suggest that postganglionic sympathetic nerves in rabbit central ear artery do not possess presynaptic facilitatory -adrenoceptors. Send offprint requests to J. Abrahamsen at the above address  相似文献   
10.
目的:初步了解WM88拮抗庆大霉素耳毒性的性能及其影响力.方法:设置庆大霉素组与庆大霉素加不同剂量WM88(10mg、20mg)的两组进行比较,观察听性脑干反应(ABR)阈值,眼震电图(ENG)的频率,了解其听功能及前庭功能的变化.仅结合耳蜗铺片琥珀酸脱氢酶(SDH)染色方法和扫描电镜观察耳蜗形态学变化.结果:听生理检查数据统计显示各组间无显著性差异;形态结果显示各组间无显著性差异.结论:本实验没有发现WM88对庆大霉素引起的耳蜗和前庭毒性有拮抗作用.  相似文献   
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