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81.
目的为了探讨地塞米松对实验性变态反应性神经炎(EAN)小鼠胸腺细胞的影响。方法应用原位末端标记法和电镜检测EAN小鼠胸腺细胞的凋亡。结果以上两种方法均发现地塞米松处理组胸腺细胞凋亡率明显高于自然病程组和正常对照组。结论地塞米松可明显增强EAN小鼠胸腺细胞凋亡。 相似文献
82.
Tartaro A. Onofrj M. Delli Pizzi C. Bonomo L. Thomas A. Fulgente T. Gambi D. 《The Italian Journal of Neurological Sciences》1996,17(1):35-42
Magnetic resonance images of optic nerves were obtained in 20 patients with acute optic neuritis (ON), and assessed by means of clinical, visual field and visual evoked potential evaluations; the imaging was repeated 1 year later. The results of the conventional Short Tau Inversion Recovery (STIR) sequence obtained using short time echo (STE-STIR: 22 msec) were compared with those of the long time echo sequence (LTE-STIR: 80 msec). The conventional STE-STIR sequence revealed lesions in 57.2% cases of acute ON and in 42.9% of the optic nerves affected by previous ON: the LTE-STIR sequence was diagnostic in 95.2% of acute ON cases and in 85% of patients with previous ON. The calculated length of the optic nerve lesions was significantly longer in the images obtained using the LTE-STIR sequence than in those obtained using conventional STE-STIR sequences.
Sommario Si descrivono i risultati ottenuti con indagini di Risonanza Magnetica (RM) dei nervi ottici (eseguite all'esordio e 12 mesi dopo) in 20 pazienti affetti da Neurite Ottica (NO) acuta, valutata in funzione della sintomatologia clinica e delle alterazioni campimetriche e del potenziale evocato visivo.Sono state analizzate le immagini RM in Short Tau Inversion Recovery (STIR) mettendo a confronto i rilievi ottenuti con sequenza Short Time Echo (STE-STIR: 22 msec) rispetto a quelli ottenuti con Long Time Echo (LTE-STIR: 20 msec). Mentre con la convenzionale STE-STIR è stato possibile rilevare lesioni a carico dei nervi ottici nel 57.2% delle Neuriti Acute e nel 42.9% delle Neuriti Pregresse, la metodica LTE-STIR è risultata diagnostica nel 95.2% delle Neuriti Acute e nel 85% delle Neuriti Pregresse.Sia nelle NO acute che nelle pregresse, la lunghezza delle lesioni a carico dei nervi ottici sono risultate significativamente maggiori rispetto a quelle ottenute con la convenzionale metodica STE-STIR.相似文献
83.
The subcutaneous pedicled V-Y advancement flap (also known as the kite flap of Dufourmentel) has been described by many authors. Its versatility in reconstructive surgery is well known, both in facial reconstructive surgery as well as surgery of the trunk and extremities. Its advantages in achieving aesthetic reconstruction in specific facial regions have been less well emphasized in the literature. The flap can be designed within natural facial creases and heals inconspicuously because of its widely based subcutaneous or muscle pedicle which incorporates venous and lymphatic drainage over most of its length. The undesirable biscuiting or flap edema frequently observed with other conventional transposition flaps is avoided. We have found the V-Y flap particularly useful in reconstructing the lower eyelid/medial canthus, supra-alar, and nasolabial regions. Our experience with over 40 such flaps is described, and technical considerations in designing and elevating the flap are discussed. 相似文献
84.
By intra-adnexal injection of glucose in the rabbit embryo, we were able to stimulate all the anomalies associated with "Amniotic Disease". Since we were even able to obtain amniotic bands, this study provides an excellent experimental model of this disease. Resulting lesions occur early in development, corresponding to the first trimester of human gestation. All of the anomalies can ultimately be explained by the destruction of the most superficial cells: epiblastic cells of the embryo and the amnion, subjacent mesenchyme, and endothelial cells. The subsequent lack of interaction between these cells and the importance of the anatomical localizations of resulting hematomas can lead to the pathogenetic approach to this disease. In light of the present study, the disease appears to be caused by an external factor within the amniotic fluid. The exact nature of the destructive agent(s) remains a mystery in man. 相似文献
85.
Mikaels A Livet J Westphal H De Lapeyrière O Ernfors P 《The European journal of neuroscience》2000,12(2):446-456
Glial cell line-derived neurotrophic factor (GDNF) family ligands promote the survival of developing motor neurons in vivo and in vitro. However, not all neurons survive with any single ligand in culture and GDNF null mutant mice display only a partial motor neuron loss. An interesting possibility is that subpopulations of motor neurons based on their function and/or their myotopic organization require distinct members of GDNF family ligands. Because responsiveness to the different ligands depends on the expression of their cognate ligand-binding receptor we have herein addressed this issue by examining the expression of GDNF-family receptors (gfr) during development and in the adult in cranial motor nuclei subpopulations. We have furthermore examined the in vivo role of GDNF for cranial motor neuron subpopulations. The shared ret receptor was expressed in all somatic, branchial and visceral cranial embryonic motor nuclei examined, showing that they are all competent to respond to GDNF family ligands during development. At early stages of development both the GDNF receptor, gfralpha1, and the neurturin (NTN) receptor, gfralpha2, were expressed in the oculomotor, facial and spinal accessory, and only gfralpha1 in the trochlear, superior salivatory, trigeminal, hypoglossal and weakly in the dorsal motor nucleus of the vagus and the ambiguous nucleus. The abducens nucleus was negative for both gfralpha1 and gfralpha2. The artemin (ART) receptor, gfralpha3, was expressed only in the superior salivatory nucleus. A motor neuron subnuclei-specific expression of gfralpha1 and gfralpha2 was seen in the facial and trigeminal nuclei which corresponded to their dependence on GDNF in null mutant mice. We found that the expression was dynamic in these nuclei, which may reflect developmental changes in their trophic factor dependency. Analysis of GDNF null mutant mice revealed that the dynamic receptor expression is regulated by the ligand in vivo, indicating that the attainment of changes in dependency could be ligand induced. Our results indicate that specific GDNF family ligands support selective muscle-motor neuron circuits during development. 相似文献
86.
针刺对实验性变态反应性神经炎TNF-α和IL-4的影响 总被引:2,自引:0,他引:2
目的 探讨肿瘤坏死因子-α(TNF-α)和白细胞介素-4(IL-4)与实验性变态反应性神经炎(EAN)发病的关系,从细胞因子水平研究针刺疗法对本病的免疫调节作用。方法 40只大鼠分为正常对照组、模型组、针刺组、药物组,建立大鼠EAN动物模型,观察大鼠发病率及致病程度,针刺组取腰。夹脊、足三里、悬钟穴,药物组用泼尼松灌胃给药。采用双抗体夹心ELISA法,检测大鼠血清的TNF-αa和IL-4的含量变化。结果 模型组TNF-α含量较正常组明显升高。针刺组和药物组均能降低TNF-α的含量,使其水平接近正常,尤以药物组抑制作用明显。IL-4的含量各组间均无明显差异。结论 提示本病存在Th1/Th2细胞因子间的失衡,其中以Th1型细胞占优势。针刺主要是通过抑制TNF-α等Th1细胞,来重建细胞因子间的平衡。 相似文献
87.
脉络宁注射液治疗半面痉挛的实验研究 总被引:1,自引:0,他引:1
目的:探讨脉络宁对半面痉挛脱髓鞘面神经的保护作用,为半面痉挛的治疗提供依据。方法:将24只新西兰大白兔随机分为对照组、脉络宁组和生理盐水组,在手术显微镜下分离出其茎乳孔处的面神经主干和颞浅动脉,使二者密切接触,以制备半面痉挛动物模型;术后第5周起对脉络宁组和生理盐水组分别自耳缘静脉推注脉络宁注射液和生理盐水持续2周;第7周取3组动物血清测定丙二醛(MDA)和超氧化物歧化酶(SOD),并处死取材行面神经光、电镜观察。结果:脉络宁组血清MDA明显低于生理盐水组(P<0.05),SOD明显高于生理盐水组(P<0.01),而与对照组比较变化不明显(P>0.05)。生理盐水组面神经纤维溃变明显,髓鞘松解分离,轴突肿胀有空泡或全部消失;脉络宁组面神经病变较轻。结论:脉络宁注射液对半面痉挛脱髓鞘面神经有明显的保护作用,对半面痉挛的治疗具有极其重要的应用价值。 相似文献
88.
Growth rate of non‐vestibular intracranial schwannomas A group of nine patients with non‐vestibular intracranial neuromas (four jugular, four facial, one trigeminal) underwent an interval scanning management policy, with serial annual magnetic resonance (MR) imaging. Tumour volume was assessed by manual measurement of the tumour area by MR imaging. Tumour volume was assessed by manual measurement of the tumour area on MR imaging axial cuts. The mean tumour size at presentation was 4.6 cm3 (range 0.7–17.8 cm3). During a mean follow‐up of 36 months (range 22–50 months), five out of nine tumours grew significantly at a rate of more than 5% of their initial volume per year. Only those tumours growing at a rate of more than 20% initial volume per year exhibited symptom progression. During a 36‐month period of interval scanning, just over 50% of non‐vestibular intracranial neuromas exhibited significant growth. Symptom progression was found to be a strong indicator of a high growth rate. This proportion exhibiting growth is higher than that demonstrated by unilateral sporadic vestibular schwannomas, but less than in patients with neurofibromatosis II. Early treatment of non‐vestibular intracranial neuromas should therefore be considered. 相似文献
89.
We conducted a meta-analysis of randomized controlled clinical trials on steroid treatment for multiple sclerosis and optic
neuritis. Of the 25 trials comparing steroids and controls without steroid treatment that we identified 12 were selected for
this review. A meta-analysis was conducted to calculate the overall odds ratio across the studies for the numbers of patients
without functional improvement and with new relapses. The trials included a total of 1714 patients: 998 with multiple sclerosis
and 716 with optic neuritis. Any type of corticosteroids or adrenocorticotropic hormone (ACTH) treatment was considered, as
was any dosage, route of administration, and length of treatment. Main outcome measures were: (a) number of multiple sclerosis
patients who did not improve by at least one point on the EDSS or equivalent scale, or number of optic neuritis patients without
complete recovery of visual acuity at 8 or 30 days and at longer follow-up; (b) number of multiple sclerosis patients with
at least one new relapse, or number of optic neuritis patients in whom definite multiple sclerosis was diagnosed at longer
follow-up. We found that corticosteroids or ACTH produced a significant improvement in disability or visual acuity at 30 days
(odds ratio 0.49; 95 % CI 0.37–0.64). The improvement was not statistically significant at longer follow-up (0.85; 95 % CI
0.67–1.09). The treatment did not significantly reduce the number of patients with relapses (0.74; 95 % CI 0.54–1.01). Both
low and high doses were effective for 30-day improvement, but only high-dose and short-term therapy were factors that identified
subgroups with some reduction in the risk of new relapse. However, the power of the statistical analysis to detect a reliable
difference in the subgroups was low. Steroid treatment is therefore effective in accelerating short-term recovery in patients
with multiple sclerosis or optic neuritis. Whether steroids are also effective in reducing the risk of relapse, and the optimal
dose and length of treatment must still be determined.
Received: 5 August 1999, Received in revised form: 29 December 1999, Accepted: 22 January 2000 相似文献
90.
面部皮损激光术后积雪甙乳膏治疗的效果 总被引:1,自引:0,他引:1
目的观察面部皮损激光术后应用积雪甙乳膏治疗的效果。方法将61例病人的面部皮损随机分为积雪甙乳膏试验组和对照组。试验组面部皮损激光术后,创面每日应用0.5 g/L碘附消毒1次,消毒后创面涂积雪甙乳膏适量;对照组创面每日应用0.5 g/L碘附消毒1次并保持创面清洁。比较两组创面愈合时间及1月与6月后创面情况积分。结果试验组创面愈合时间明显短于对照组,差异有显著性(t=3.30,P<0.01)。两组1月后创面情况积分比较差异有显著性(t=4.04,P<0.01);两组6月后创面情况积分比较差异有显著性(t=7.81,P<0.01)。结论积雪甙乳膏具有促进创面愈合、防治病理性瘢痕形成的作用,面部皮损激光术后应用积雪甙乳膏治疗效果确切,值得进一步研究和临床应用。 相似文献