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81.
慢性癫痫大鼠脑组织生长抑素受体功能的变化   总被引:1,自引:0,他引:1  
探讨癫痫发病的生化机制。方法用125I-SOM作为配基,采用放射性配基受体结合分析法,对戊四氮诱导的慢性癫痫大鼠海马生长抑素(SOM)受体功能进行了测定。结果慢性癫痫大鼠及对照组海马SOM受体的Bmax值分别为246.0±18.2pmol/g蛋白质及220.0±15.3pmol/g蛋白质,Kd值分别为4.19±0.34nmol/L及3.89±0.22nmol/L。常用的抗痫药卡马西平(CBZ)、丙戌酸钠(VPA)及钙桔抗剂尼莫地平(NIM)能降低受体的亲和力,而苯妥因钠(PHT)则无影响。结论SOM受体活性增高在癫痫发病中起着重要作用,常用抗痫药的抗痫活性可能与其降低SOM受体活性有关。  相似文献   
82.
From a Pediatric Rheumatology Clinic 361 children diagnosed as juvenile rheumatoid arthritis (JRA) according to American Rheumatism Association-JRA criteria were studied retrospectively for their clinico-immunological profile. The mean age of onset in systemic, pauciarticular and polyarticular onset, JRA subtypes were 5.2, 6.8 and 7.2 years respectively. There was male preponderance in systemic and pauciarticular JRA. In seropositive polyarticular JRA, girls outnumbered boys. The frequency of occurence of systemic, pauciarticular and polyarticular disease was 87 (24%), 108 (30%) and 166 (46%) respectively. The systemic onset disease was dominated by extra-articular manifestations in terms of fever (100%), rash (57%), hepatomegaly (51%) and lymphadenopathy (25%). The pauci- and polyarticular illnesses were commonly dominated by joint involvement, morning stiffness, and in few patients, by extra-articular manifestations also. The joints were involved symmetrically. Most commonly involved joints in order of decreasing frequency were knee, ankle, wrist and elbow in all the subtypes. Anemia and leucocytosis were observed in majority with higher frequency in systemic onset JRA. The rheumatoid factor (RF) was present in 15% of polyarticular JRA. RF was also present in 7 and 9% of patients with pauciarticular and systemic subtypes respectively. The antinuclear antibody was positive in only 3 out of 66 patients in whom the test was carried out. The demographic profile and trends in clinical features were similar to the studies reported on caucasian population with difference in the actual frequency of various clinical features.  相似文献   
83.
Important inroads are being made into understanding the pathophysiology of diarrhea. Clear understanding of key mechanisms should suggest new approaches to combat disease. Exciting developments are occurring in terms of super-ORS solutions, particularly with the promise of short chained glucose polymers and glutamine. Perhaps the most important development is the prospect of a good rotavirus vaccine being available before the end of the decade. Chronic diarrhea seems to be on the increase globally, probably because of the success of ORS. The mechanisms that lead to mucosal injury are elusive, and therapy still largely supportive and empiric. Celiac disease continues to be a puzzle, because of the uncomfortable feeling that a majority of cases may be missed because of atypical presentations. The successful use of long term parenteral nutrition has allowed survival and better charaterization of cases that otherwise would have perished as ‘lethal protracted diarrhea’. Microvillus inclusion disease may be the commonest congenital secretory diarrhea. The role of the recently reported high prevalence of glucoamlase deficiency may be important. Lastly, attention to micronutrients, particularly low vitamin A and probably zinc may prove to be important in prevention and amelioration of diarrhea and growth failure.  相似文献   
84.
Summary In 20 patients with an acute exacerbation of chronic respiratory tract infection the effectiveness of oral erythromicin succinate 3×500 mg daily has been tested. The duration of treatment was 10 days in all cases. The criteria of success, in addition to the clinical findings, were the results of bacteriological investigations and assessment of the appearance of the sputum. In all patients sputum and serum concentrations or erythromicin were determined. All pathogens isolated from the sputum of the patients were erythromicin-sensitive. One instance of development of resistance was observed. The drug was well tolerated.  相似文献   
85.
Summary In the irreversible stage of lymphedema corrective surgery is often mandatory. A choice has to be made between two different basic selective procedures. As no totally satisfactory surgical method has as yet been established surgical management is difficult and implies considerable personal responsibility. This is a report on the long-term results of operations carried out on 16 patients between 1958 and 1979 using the so called Charles procedure. It concludes that this radical operation gives an acceptable long-term result in long-standing, elephantiastic primary lymphedema of the lower extremity.  相似文献   
86.
Variant X-linked chronic granulomatous disease (CGD) is characterised by a decreased but still measurable respiratory burst and cytochrome b content of phagocytes resulting in a clinically milder form of the disease. We examined the in vivo effect of recombinant human granulocyte-macrophage colony stimulating factor (rh-GM-CSF) on the neutrophil functions of a patient treated for liver abscess. The number of white blood cells was markedly increased at the highest dose of GM-CSF injected (30 g/kg per day). This was mainly due to a large increase in eosinophils and to a lesser extent in neutrophils. No change in the deficient neutrophil respiratory burst nitroblue tetrazolium (NBT)-reduction, superoxide (O 2 )-production and cytochrome b content was observed during 6 weeks of therapy with increasing doses of GM-CSF. No significant clinical improvement of the liver abscess was observed during treatment with GM-CSF.  相似文献   
87.
Summary The role of PGE2 in the sensitization of highthreshold tarsal joint mechanoreceptors (putative nociceptors) has been investigated in 11 arthritic and 16 normal rats. Injections of a low dose of Freund's complete adjuvant at multiple sites into the tissues surrounding the ankle joint induced a chronic unilateral monoarthritis in the injected limb. Measurements of both spontaneous activity and responses of tarsal joint mechanoreceptors to repeated graded mechanical stimuli were made. All of the mechanoreceptors examined had afferent fibres with conduction velocities in the C or A- range. Using this new model of joint inflammation we have shown that lysine acetylsalicylate reduces the mechanical sensitivity of these joint mechanoreceptors and reduces the spontaneous activity in afferent nerve fibres. Prostaglandin E2 is unable to restore either the spontaneous activity in the afferent axon or the mechanical sensitivity of tarsal joint mechanoreceptors after lysine acetylsalicylate in the arthritic rat. Similarly, PGE2 does not sensitize or excite tarsal joint mechanoreceptors in the normal rat. In the normal rat, however, PGE2 potentiates the excitatory action of bradykinin and enhances the sensitizing effect of bradykinin on the responses of joint mechanoreceptors to mechanical stimulation when both substances are injected simultaneously. These results indicate that PGE2 is not important in the sensitization of these joint mechanoreceptors in this model of chronic joint inflammation but that in other circumstances PGE2 may be able to contribute to a sensitization of joint mechanoreceptors by enhancing the action of bradykinin.  相似文献   
88.
Summary The qualitative and quantitative synaptology of flat synaptic vesicle containing F type terminals was analysed in normal and in chronically cortically deafferented dorsal Lateral Geniculate Nucleus (dLGN) of the cat using an electron microscopic immunogold technique for visualization of GABA. A direct correlation was found between the density (number of gold particles) of GABA immunostaining and the number of synaptic vesicles in different F terminals. This suggested a quantitative relationship between transmitter content and the number of vesicles in the labeled terminals. Not only the number but also the size of synaptic vesicles was found to be different in the two main groups of F profiles, i.e. the axonal F1 and dendritic F2 terminals. Measurement of the size of synaptic vesicles in F1 axon terminals revealed two subpopulations of these endings: F11 and F12 terminals with vesicle diameters of 31.56 ± 0.08 nm and 33.73 ± 0.12 nm (P < 0.01; Chi2 test) respectively. The size of synaptic vesicles in axonal F12 terminals was identical to that found in F2 dendritic profiles, suggesting that both processes belonged to the same, intrageniculate (interneuronal) cell population. F11 terminals, however, appeared to be axonal endings of extrageniculate (most probably of perigeniculate) neurons. Quantitative analysis of the two types of GABAergic axon terminals revealed the geniculocortical relay cells to be the main postsynaptic targets for F11 (extrageniculate) terminals while F12 axons terminated equally on both interneurons and relay cells. Following chronic decortication of the dLGN, the distribution pattern of both GABAergic axonal types had changed considerably. As a result of a severe loss in relay cells, more F11 and F12 axon terminals were found on GABA-containing interneuronal processes than on relay cells. An increase in the number of F1 axonal terminals per neuron was also revealed, (particularly on GABAergic interneurons), suggesting a compensatory reactive synaptogenesis by both F axonal types following decortication.  相似文献   
89.
Summary The turnover of noradrenaline (NA) and dopamine (DA) was estimated in various rat brain regions by measuring the depletion of the amines after inhibition of their biosynthesis by -methyltyrosine. Acute treatment with clonidine (0.1 mg/kg) reduced NA turnover in the brain stem, hypothalamus and rest of the brain but had no effect on DA turnover in the corpus striatum and rest of the brain. After chronic clonidine treatment (0.1 mg/kg, twice daily for 15 days), NA turnover was not affected by an additional injection of clonidine in the brain stem or in the hypothalamus but was still markedly reduced in the rest of the brain. In addition, DA turnover was reduced in the corpus striatum and rest of the brain, an effect which was also observed after a single injection of a high dose of clonidine (1 mg/kg). These findings suggest that a chronic administration of clonidine may cause regionally differential changes in the sensitivity of central NA receptors.  相似文献   
90.
The effect of early splenectomy and of polychemotherapy with hydroxyurea, busulfan, and alternate bimonthly courses of arabinosyl cytosine and vincristine plus prednisone, was evaluated in 139 previously untreated patients with chronic myeloid leukemia (CML), consecutively admitted to 18 hospitals from March 1973 to October 1974. Fifty-six patients were splenectomized and 83 patients were not splenectomized. Splenectomy did not influence the duration of chronic and blastic phase, and did not prolong survival. The prognosis of high risk patients was not improved. During the chronic phase, high platelet counts were more frequent in splenectomy group, and five patients developed thrombotic or thromboembolic complications, 5 to 19 months after the operation. The median survival of the whole group was 50 months, with 32 of 139 patients (actuarial proportion 30%) remaining alive 72 months after diagnosis, but the slope of the survival curve was similar to that of historical controls. The results of this trial suggests that new strategies should be developed for the therapy of CML.  相似文献   
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