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1.
肛直肠抑制反射时门静脉血中P物质变化   总被引:1,自引:0,他引:1  
目的探讨肛直肠抑制反射(RAIR)时门静脉血中P物质(SP)的变化规律及外源性内脏神经对其变化的影响。方法将实验大白鼠分为7组,其中6组先按去与不去直肠肛管外源性内脏神经支配而分为不去神经和去神经两大组,每组中又按Foley导管上气囊置入直肠腔中的位置分为2、4、6cm组;同时再设1个对照组,将Foley导管置入直肠腔中,但不注水扩张球囊。检测并比较在直肠腔内刺激后,各组门静脉血中的SP值及变化情况。结果去神经组中2、4cm组与不去神经组之间及对照组之间,门静脉血中SP值变化比较,P〉0.05,差异无统计学意义。不去神经组中的6cm组与对照组及去神经组中2cm和4cm组之间SP值比较,P〈0.01,差异有统计学意义;去神经组和不去神经组中的6cm组之间SP值比较,P〈0.01,差异有统计学意义。结论直肠腔内上部的刺激不引出RAIR可能与该部位的刺激使内括约肌兴奋性递质(SP)的释放有关;外源性内脏神经对RAIR中门静脉血的SP变化有调控作用。  相似文献   
2.
This paper outlines the impact of granulocyte‐colony stimulating factor (G‐CSF) used as a single modality therapy in 17 patients with secondary autoimmune neutropenia (S‐AIN) who had been treated a multiple number of times previously. Fifteen of these patients had demonstrable antineutrophil antibodies and two had cellular S‐AIN with haemopoietic inhibitory T‐cells present in the marrow. Prior to treatment, all had had problems with infection. All patients responded within 7 days of commencement of treatment. Provided G‐CSF neutrophil counts were maintained above 1 × 109/l, no further infections occurred. This was achievable by using G‐CSF administered as infrequently as once every 8 days. Eight of the 17 patients remained on G‐CSF, although five switched to the glycosylated form because of side‐effects. None have developed osteoporosis despite 47.29 patient years of total experience with G‐CSF. In conclusion both glycosylated and nonglycosylated G‐CSF can be used effectively in treating AIN on a long‐term basis.  相似文献   
3.
蜂王浆冻干粉对小鼠肿瘤的抑制作用   总被引:4,自引:0,他引:4  
目的研究蜂王浆冻干粉对小鼠肿瘤的抑制作用.方法按每公斤体重0g、0.25g、0.50g、0.75g设对照及低、中、高3个剂量组,经口给予蜂王浆冻干粉30d后,接种小鼠肉瘤180(S180)和艾氏癌腹水型(EAC)两个瘤种.结果在两次重复的小鼠S180和EAC抑瘤试验中发现中剂量组瘤重明显低于阴性对照组(P<0.05),抑制率可达34%;中剂量组荷瘤小鼠平均生存时间均明显高于对照组(P<0.05).结论蜂王浆冻干粉具有抑制肿瘤的作用.  相似文献   
4.
Bacterial and fungal peritonitis is associated with a high riskof morbidity and mortality in patients undergoing continuousambulatory peritoneal dialysis (CAPD). Impaired cellular hostdefence in the peritoneal cavity underlies this risk. Two granulocyteinhibitory proteins with a molecular weight of 28000 dalton(GIP I) and about 9500 dalton (GIP II) with homology to light-chainproteins and beta respectively, were isolated from peritonealdialysis effluents. In vitro, both granulocyte inhibitory proteinsinhibit PMNL glucose uptake, phagocytosis and intracellularkilling of bacteria. The IC50 of GIP I or GIP II required forinhibition of half-maximal FMLP-induced or PMA-stimulated PMNLfunction was found to be in the nanomolar range, suggestingvery specific inhibition. These data may explain, at least inpart, defective local cellular host defence in CAPD patients.  相似文献   
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6.
以液体稀释法比较了自制与进口十六烷基吡啶作用于4种口腔常见微生物的最低抑菌浓度和最低杀菌浓度的实验结果,经t检验证明两者间无显著差异,提示自制氯化十六烷基吡啶的药效质量可靠。并就控制接种菌量及杀菌机理等问题作了初步探讨。  相似文献   
7.
50种传统清热解毒药的抑菌实验   总被引:13,自引:1,他引:12  
华娟  周明康 《中药材》1995,18(5):255-258
本文报告了传统药物文献收载的50种清热解毒药的抑菌实验结果。显示抑菌作用的有41种,占82%。对阳性球菌显示有抑菌作用的有36种;对阴性杆菌显示有抑菌作用的有24种。其中的地胡椒、金果榄、毛果算盘子等显示有较广的抗菌效应,值得进一步研究。  相似文献   
8.
Summary The influence of antiepileptics on the evolution of rat amygdaloid kindling was studied.Under placebo conditions clonic convulsions and a spike-wave EEG pattern developed. Diazepam, clonazepam, clobazam and phenobarbital were most effective in suppressing the evolution of kindling; the effects of valproate sodium, ethosuximide and acetazolamide were somewhat less pronounced in this respect. Carbamazepine, oxcarbazepine and phenytoin, on the other hand, enhanced kindling development, i.e. the increase in duration of after-discharge was faster than in the placebo group. The results indicate that under the above experimental conditions drugs with no anti-absence component can be distinguished from those with an anti-absence component. The mechanism of action underlying the observed effects is not yet known; the hypothesis that under special conditions protective inhibitory neuronal activity can develop to absence type seizures is proposed.  相似文献   
9.
The purpose of this study was to determine whether the late component of somatosensory evoked potentials (SEP) induced by electrical tooth stimulation and pain intensity are inhibited by heterotopic ischemic stimulation. The tourniquet pressure with 50 mmHg greater than the individual's systolic pressure was applied to the left upper arm for 10 min as ischemic conditioning stimulation. The late component of SEP and visual analogue scale (VAS) were recorded at 4 times and both were significantly decreased when ischemic conditioning stimulation was applied. The maximum reductions in SEP amplitude and the VAS value were 26.1% and 21.2%, respectively, during ischemic conditioning stimulation. After-effect was observed 5 min after removal of the conditioning stimulation. The present study revealed that heterotopic ischemic stimulation attenuated the late component of SEP induced by electrical tooth stimulation, triggering diffuse noxious inhibitory controls (DNIC) and after-effects in the trigeminal nerve territory. It was also suggested that the DNIC effect differs, depending on the intensity, kind, and quality of the test and conditioning stimuli.  相似文献   
10.
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