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81.
微血管减压术治疗舌咽神经痛16例临床分析   总被引:4,自引:1,他引:3  
目的 研究舌咽神经痛 (glossopharyngealneuralgia,GPN)手术治疗的最佳术式 ,评估微血管减压手术(microvasculardecompression ,MVD)的效果、并发症和随访结果 ,探讨可能的治疗机制。方法  2 0 0 0年 12月到2 0 0 3年 10月间 ,16例GPN患者接受了MVD ,无一例行神经根切断术。患者全部进行了电话或信件随访。结果 15例患者术后疼痛消失 ,1例患者为不典型GPN ,术后疼痛减轻。 1例患者术后出现轻度声音嘶哑和吞咽困难 ,1例患者出现偶发干咳。本组患者平均随访时间为 14 .1± 6 .3月 ,随访期间无一例复发。结论 MVD是治疗舌咽神经痛的一种安全、有效的手术方式 ,尤其适用于典型的GPN患者。  相似文献   
82.
The mechanisms underlying neurologic deficits and delayed neuronal death after ischemia are not fully understood. In the present study, we report that transient cerebral ischemia induces accumulation of ubiquitinated proteins (ubi-proteins) in postsynaptic densities (PSDs). By immunoelectron microscopy, we demonstrated that ubi-proteins were highly accumulated in PSD structures after ischemia. On Western blots, ubi-proteins were markedly increased in purified PSDs at 30 minutes of reperfusion, and the increase persisted until cell death in the CA1 region after ischemia. In the resistant DG area, however, the changes were transient and significantly less pronounced. Deposition of ubi-proteins in PSDs after ischemia correlates well with PSD structural damage in the CA1 region as viewed by electron microscopy. These results suggest that the ubiquitin-proteasome system fails to repair and remove damaged proteins in PSDs. The changes may demolish synaptic neurotransmission, contribute to neurologic deficits, and eventually lead to delayed neuronal death after transient cerebral ischemia.  相似文献   
83.
T lymphocytes play a fundamental role in the initiation and regulation of chronic inflammatory responses in patients with asthma. CD69 is an early marker of T‐cell activation. The levels of intercellular adhesion molecule‐1 (ICAM‐1, CD54) and L ‐selectin have been reported to increase in patients with allergic diseases and asthma. The present study was therefore undertaken to investigate the expression of CD69, CD54, and L ‐selectin by T lymphocytes of children with asthma, before and after immunotherapy. Eighteen children newly diagnosed with asthma, 11 good and nine poor responders to immunotherapy, and 16 normal subjects, were enrolled in this study. The percentages of CD69+, CD54+, and CD62L+ cells in T lymphocytes were measured by using flow cytometry. The levels of CD69, CD54, and CD62L in serum and culture supernatants were determined by using enzyme‐linked immunosorbent assay (ELISA). The expression of CD69 and CD54 on CD3+ T lymphocytes was significantly higher in children with asthma than in control patients. All the patient groups expressed (spontaneously and following stimulation with phorbol myristate acetate and ionomycin together with mite‐extract proteins) greater amounts of CD69 and CD54 than did control subjects. With long‐term immunotherapy, the percentages of CD69+ and CD54+ T lymphocytes were significantly lower in patients with a good response to immunotherapy. Our results also showed significantly lower serum L ‐selectin levels following immunotherapy. In conclusion, successful immunotherapy resulted in decreased expression and production of CD69 and CD54. These results may explain, in part, the clinical efficacy of immunotherapy.  相似文献   
84.
Parvalbumin 3 is an Abundant Ca2+ Buffer in Hair Cells   总被引:3,自引:0,他引:3  
Ca2+ signaling serves distinct purposes in different parts of a hair cell. The Ca2+ concentration in stereocilia regulates adaptation and, through rapid transduction-channel reclosure, underlies amplification of mechanical signals. In presynaptic active zones, Ca2+ mediates the exocytotic release of afferent neurotransmitter. At efferent synapses, Ca2+ activates the K+ channels that dominate the inhibitory postsynaptic potential. A copious supply of diffusible protein buffer isolates the three signals by restricting the spread of free Ca2+ and limiting the duration of its action. Using cDNA subtraction and a gene expression assay based on in situ hybridization, we detected abundant expression of mRNAs encoding the Ca2+ buffer parvalbumin 3 in bullfrog saccular and chicken cochlear hair cells. We cloned cDNAs encoding this protein from the corresponding inner-ear libraries and raised antisera against recombinant bullfrog parvalbumin 3. Immunohistochemical labeling indicated that parvalbumin 3 is a prominent Ca2+-binding protein in the compact, cylindrical hair cells of the bullfrog's sacculus, and occurs as well in the narrow, peanut-shaped hair cells of that organ. Using quantitative Western blot analysis, we ascertained that the concentration of parvalbumin 3 in saccular hair cells is approximately 3 mM. Parvalbumin 3 is therefore a significant mobile Ca2+ buffer, and perhaps the dominant buffer, in many types of hair cell. Moreover, parvalbumin 3 provides an early marker for developing hair cells in the frog, chicken, and zebrafish.  相似文献   
85.
The feasibility and early results of a new technique of outpatient proctoscopic coagulation of haemorrhoids by means of an electronic probe (Ultroid®, Microvasive Inc., USA) were evaluated in comparison to conventional injection sclerotherapy. Age, symptom and sex-matched groups were analysed before and 6 weeks after outpatient treatment, using scoring systems (n=51). A mean of 6.2±0.4 ml of phenol in oil were injected over 2.4±0.2 min compared to a mean current of 15.8 ±0.2 mA over a period of 11.9±0.8 min (p<0.001, treatment time). Sclerotherapy was found significantly less tedious than coagulation. More patients complained of discomfort during coagulation, but the difference in tolerance scores between the 2 groups was not significant. Three patients in the coagulation group but none in the injection group refused to be treated by the same method again due to discomfort. Significant benefits were achieved by both modes of treatment after 6 weeks. The early cure rates for bleeding were 84% for sclerotherapy and 64% for coagulation (p=0.2) and for prolapse 56% and 44% respectively (p=0.72). Injection sclerotherapy is preferable to Ultroid® coagulation for the outpatient treatment of haemorrhoids because it is a quicker, less tedious and more comfortable procedure with equally effective early results.
Résumé La réalisation et les premiers résultats d'une nouvelle technique de coagulation ambulatoire des hémorroïdes au moyen d'une sonde électronique (Ultroïd, Microvasive inc. USA) on été évalués par comparaison avec la sclérothérapie conventionnelle. Deux groupes appariés selon l'âge, les signes et le sexe ont été analysés avant et six semaines après un traitement ambulatoire en utilisant un score (n=51). Une moyenne de 6,2±0,4 ml d'huile phéniquée a été injectée en 2,4±0,2 mn comparée à une application de courant moyen de 15,8±0,2 mA dans une période de 11,9±0,8 mn (p<0,001, temps de traitement). La sclérothérapie a été trouvée moins pénible que la coagulation. Plus de malades se plaignaient d'inconfort durant la coagulation mais la différence de tolérance n'était pas significative entre les deux groupes. Trois malades dans le groupe de coagulation ont refusé de poursuivre le traitement en raison du disconfort contre aucun malade dans le groupe d'injection. Les résultats furent bons dans les deux groupes après six semaines. Les résultats immédiats pour les saignements étaient de 84% et de 64% pour la coagulation (p=0,2) et pour les procidences de 56% pour la scléro-thérapie contre 44% pour la coagulation (p=0,72). Les injections sclérosantes sont préférables à la coagulation Ultroid comme traitement ambulatoire des hémorroïdes car il s'agit d'un procédé plus rapide, moins pénible et plus confortable avec des résultats immédiats aussi bons.


Paper presented at the Spring Meeting of the British Society of Gastroenterology, University of Warwick, UK, March 1990  相似文献   
86.
The ability of nicotine to induce a cytoprotective or neuroprotective action occurs through several down-stream mechanisms. One possibility is that the drug increases the expression of tyrosine kinase A (TrkA) nerve growth factor (NGF) receptors. Certain β-amyloid peptides (e.g., Aβ1–42) have been shown to bind with high affinity to α7 nicotinic receptors and thus interfere with a potentially neurotrophic influence. Treatment of differentiated PC-12 cells with nicotine produced a concentration-dependent increase in cell-surface TrkA receptors that occurred concomitantly with cytoprotection. The effect of nicotine was blocked by either of the α7 receptor antagonists α-bungarotoxin (α-BTX) or methyllycaconatine. The cytoprotective action of nicotine also was inhibited by pretreatment with 10–100 nM Aβ1–42. Nicotine also was administered (four injections of 30 μg, spaced evenly over 24 h) to rats by direct injection into a lateral cerebral ventricle. Brain TrkA expression was increased significantly in hippocampus and entorhinal cortex (up to 32% above control), with no changes found in cerebral cortex or hypothalamus. The nicotine-induced increases in TrKA expression in hippocampus and entorhinal cortex were significantly inhibited by 10 μg α-BTX or by 10 nmol Aβ1–42. Therefore, physiologically relevant concentrations of Aβ1–42 can prevent nicotine-induced TrkA receptor expression in brain regions containing cholinergic neurons susceptible to the neurotoxicity associated with Alzheimer’s disease.  相似文献   
87.
目的 解决南方红豆杉细胞生长缓慢及代谢水平低下的问题。方法 对对数期(20d)和静止期(30d)的红豆杉细胞分别进行继代,在整个生长周期中测定了培养基中的碳源、氮源、磷酸盐的变化并分析了红豆杉细胞生长及紫杉醇的合成情况。结果 对数期继代细胞吸收碳源和硝态氮早于静止期继代的细胞,且前者的比生长速度是后者的1.5倍,紫杉醇含量提高了近4倍。结论 对数期继代有利于生物量的积累及紫杉醇的合成。  相似文献   
88.
小切口胆囊切除术108例临床观察   总被引:1,自引:0,他引:1  
本文报告腹部切口5-8cm的小切口胆囊切除术108例,与同期大切口胆囊切除术相比,具有创伤较小、恢复较快、并发症少、切口疤痕小的优点,虽不如腹腔镜胆囊切除术(LC)的疼痛轻、恢复快,但并症比LC少,只要适应症选择得当,在术者的经验和技术较成熟的情况下,不昔为一种可供选择的方法。  相似文献   
89.
In order to investigate the antagonistic effect of Glycyrrhiza Uralensis Fish (GUF) and Chelidonium maJus L (CML) on gastrccarcinogenesis induced by MNNG in Wastar rats, we treated the rats with MNNG alone (group 1) and with MNNG plus GUF and CML (group 2 and 3) respectively. The incidence of infiltrating adenocarcinoma of the glandular stomach and duodenum in group 2 was significantly lower than that in group 1 (26.7% vs. 67.8%). The differentiation and aggressivenees of carcinomas occured in group 2 were much better and mild than those in group 1. Present study also demonstrated that the inhibitory effect of CML on proliferation of human stomach carcinoma cell line MGC-803 was very remarkable; in addition, GUF and CML were able to antagonise the mutagenic activation of MNNG. These results suggest that GUF and CML may be empoyed in prevention of gastric carcinoma.  相似文献   
90.
短暂性脑缺血发作患者血浆中TXB2和PGF1α含量检测   总被引:3,自引:0,他引:3  
本文用放射免疫法测定47例短暂性脑缺血发作(TIA)患者血浆中血栓素B_2(TXB_2)和6酮-前列腺F_(1α)(PGF_(1α))的含量。结果发现TIA患者血浆中TXB_2含量增高,PGF_(1α)降低;头颅CT或MRI示有小灶性梗塞者及TIA发作持续时间长于30min者TXB_2升高和PGF_(1α)降低更显著。治疗3个月后,血浆PGF_(1α)显著增高。TXB_2和PGF_(1α)在体内的失平衡是急性脑血管疾病发病的重要机理之一。  相似文献   
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