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91.
Chen Li Liu Maryann E Martone Bingren R Hu 《Journal of cerebral blood flow and metabolism》2004,24(11):1219-1225
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
92.
Jing‐Long Huang Liang‐Shiou Ou Ching‐Hsiung Tsao Li‐Chen Chen Ming‐Ling Kuo 《Pediatric allergy and immunology》2002,13(6):426-433
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
93.
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.
Paper presented at the Spring Meeting of the British Society of Gastroenterology, University of Warwick, UK, March 1990 相似文献
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
94.
Xinyu D. Li Esperanza Arias Ramamohana R. Jonnala Shyamala Mruthinti Jerry J. Buccafusco 《Journal of molecular neuroscience : MN》1996,27(3):325-336
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
95.
96.
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
97.
Jiyou Li Yuquan Xie Guizhi Shi Heling Sun Xinhua Ji Maolin Jin Boqin Yang Mingsheng Wang 《中国癌症研究》1992,4(2):10-12
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
98.
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
99.
100.
Principles for managing penetrating craniocerebral injuries caused by firearm missiles 总被引:1,自引:0,他引:1
X Zhang S Y Yi W P Liu Z W Zhang L G Wang A M Li 《Journal of clinical neuroscience》1996,3(3):229-233
Penetrating craniocerebral firearm injuries remain one of the most lethal causes of all trauma and are common both in war or peace time. Data were reviewed for 4140 severely head-injured patients (Glasgow Coma Scale (GCS) scores 3-8) treated at Xi-Jing Hospital between 1973 and 1993; 51 of these patients had acute penetrating craniocerebral injuries caused by firearm missiles. These patients consisted of 46 males (90.2%) and 5 females (9.8%) ranging in age from 3 months to 48 years (median 22.4 years). The lesion types included 2 tangential wounds, 37 tubular wounds and 12 through-and-through wounds. All cases were urgent with the patients in severe and unstable states. After emergency treatment and operation, 5 cases died (9.8%). Follow up studies at three months showed that 23 cases (45.1%) had made a good recovery. Moderate disability, severe disability and vegetative states in this series were 29.4%, 13.7% and 2.0% respectively. Long term follow up studies indicated that 32 were able to resume their occupation. The principles for managing penetrating craniocerebral firearm injuries and suggestions for operation are discussed. 相似文献