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51.
Tumor necrosis factor-alpha (TNFalpha) and Fas are induced after traumatic brain injury (TBI); however, their functional roles are incompletely understood. Using controlled cortical impact (CCI) and mice deficient in TNFalpha, Fas, or both (TNFalpha/Fas-/-), we hypothesized that TNFalpha and Fas receptor mediate secondary TBI in a redundant manner. Compared with wild type (WT), TNFalpha/Fas-/- mice had improved motor performance from 1 to 4 days (P<0.05), improved spatial memory acquisition at 8 to 14 days (P<0.05), and decreased brain lesion size at 2 and 6 weeks after CCI (P<0.05). Protection in TNFalpha/Fas-/- mice from histopathological and motor deficits was reversed by reconstitution with recombinant TNFalpha before CCI, and TNFalpha-/- mice administered anti-Fas ligand antibodies had improved spatial memory acquisition versus similarly treated WT mice (P<0.05). Tumor necrosis factor-alpha/Fas-/- mice had decreased the numbers of cortical cells with plasmalemma damage at 6 h (P<0.05 versus WT), and reduced matrix metalloproteinase-9 activity in injured brain at 48 and 72 h after CCI. In immature mice subjected to CCI, genetic inhibition of TNFalpha and Fas conferred beneficial effects on histopathology and spatial memory acquisition in adulthood (both P<0.05 versus WT), suggesting that the beneficial effects of TNFalpha/Fas inhibition may be permanent. The data suggest that redundant signaling pathways initiated by TNFalpha and Fas play pivotal roles in the pathogenesis of TBI, and that biochemical mechanisms downstream of TNFalpha/Fas may be novel therapeutic targets to limit neurological sequelae in children and adults with severe TBI.  相似文献   
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53.
对我省医学临床教学基地评审结果进行分析,就大部分基地教学意识不强、教学设施不完善、教学条件有待改善、师资队伍素质水平不高等问题进行了阐述,并针对存在的问题提出建议和思考,从建章立制规范管理、加强建设、提供保障、重视培训、提高素质、强化管理、创新机制等方面进行探索,希望能使我省医学临床教学基地质量得以提高、完善,为我省培养一流的医学专业人才奠定基础.  相似文献   
54.
目的 :探讨蝌蝌提取液 (T871)对白血病细胞的诱导分化作用。方法 :利用细胞生长曲线、形态学观察、细胞免疫化学及原位mRNA杂交和完整细胞原位斑点印迹技术 ,观察了T871诱导HL 60细胞分化的作用和分化过程中癌基因c myc、c myb表达的变化。结果 :T871能抑制HL 60细胞的增殖 ,形态学表现为类似单核 /巨噬细胞 ,同时T871还能使HL 60细胞的NBT还原能力、ANAE活性显著增强 ,同时伴有癌基因c myc、c mybmRNA表达的下调。结论 :T871能诱导HL 60细胞向单核 /巨噬细胞方向分化 ,c myc、c myb癌基因可能参与了此过程  相似文献   
55.
运动训练对雄性大鼠垂体─性腺轴功能的影响   总被引:3,自引:2,他引:1  
本研究通过使用自己制造的大鼠流动水游泳池,对雄性大鼠进行了6周递增负荷的游泳训练,以此来探讨运动训练对大鼠垂体-性腺轴功能的影响,结果显示:与安静对照大鼠相比,训练大鼠的一般状态较差,血清睾酮水平显著降低(P<0.05),血清睾酮/皮质酮比值平均降低了30%以上;而血清LH和FSH水平未见明显变化。通过对大鼠睾丸组织LH/CG受体的测定,显示运动训练虽未引起其最大结合量的改变,却能使其解离常数显著升高(P<0.05)。提示此种训练可能通过降低睾丸LH/CG受体对垂体分泌LH的亲和力,从而影响睾酮的合成。  相似文献   
56.
抗体阴性重症肌无力发病与凝集素之间关系研究   总被引:2,自引:0,他引:2  
借助研究抗体阴性重症肌无力(MG)发病与凝集素之间的关系,以阐明其发病过程是否与凝集素有关。方法观察伴刀豆球蛋白A(ConA)和麦胚凝集素(Triticum)及其凝集素-糖复合物对TE671细胞表达的乙酰胆碱受体(AChR)功能的作用,以及对α-BuTx结合试验的影响。结果有两种凝集素对AChR功能均有抑制作用,抑制率(%)分别为54±14(n=11)和47±16(n=10),此作用可被3种糖抑制,抑制率(%)分别为:95±5(n=5)和84±8(n=5);69±6(n=4)和65±5(n=4);39±4(n=5)和57±6(n=5);ConA抑制α-BuTx结合试验,而Triticum则不能。结论Triticum和抗体阴性MG患者非IgG部分对AChR功能和α-BuTx结合试验的作用类同或一致,表明抗体阴性MG患者非IgG部分中的内源性Triticum样糖蛋白在其发病过程中起重要作用。  相似文献   
57.
Background: Recent development of extracorporeal magnetic stimulation (ECMS) which uses current‐changing magnetic fields allows the induction of electrical stimulation in the desired deep tissue. Recent study showed the sacral nerve stimulation reduces corticoanal excitability that may play a functional role in anal continence mechanisms. Preliminary study shows that ECMS of sacral nerve can modify pelvic floor function and expel rectal balloon in patients with pelvic floor dyssynergia (PFD). Aims: To evaluate the effect of ECMS compared with biofeedback therapy (BF) in patients with PFD. Methods and Materials: Thirty‐eight patients who fulfilled Rome II criteria for PFD by colon transit time and anorectal function tests, were randomly treated with 8 sessions of ECMS (2/weeks; n = 19) at prone position or BF (2/weeks; n = 19) at sitting position. Stimulation parameters were set at 50–80% of maximum intensity, 10 and 50 Hz frequency, 3 s burst length with 3 and 6 s off using arm‐typed stimulator (BioCom‐1000, Mcube Co., Korea). Symptom scores for constipation with/without anorectal function test were repeatedly measured after each treatment. Response was defined as 50% or more decreased symptom score after treatment (partial response: 30–50%, poor: <30%). Results: Fifteen patients (age 49.1 ± 13.4 years, mean ± SD; 4 men) completed 8 session of BF and 14 patients (54.5 ± 17.6 years, 3 men) completed 8 session of ECMS. Four patients of BF group discontinued treatment due to unsatisfactory therapeutic effect (n = 1) and withdrew consent (n = 3) and 5 patients of ECMS group discontinued treatment because of same reasons (n = 1, 4). Total symptom scores were significantly decreased after treatment of 8 session in both treatment groups (13.4 ± 6.6 vs. 4.3 ± 4.0 for BF, p = 0.009; 14.9 ± 5.6 vs. 3.4 ± 4.0 for ECMS, p < 0.001). Bowel movements per week were also significantly increased after treatment in both groups (median 2 vs. 7 for BF, p = 0.035; median 2 vs. 7 for ECMS, p = 0.008). Thirteen out of 15 patients showed response in BF group and 12 out of 14 showed good response in ECMS group. No adverse effects in both groups. Conclusions: ECMS is as effective as BF for the treatment of PFD. Long‐term effect of ECMS for the patients with pelvic floor dyssynergia need to be evaluated in the near future.  相似文献   
58.
This report describes our experience with a 60 year old male who suffered from a recrudescence of groove pancreatitis. He had been treated by conservative medication therapy by proton pump inhibitor used for therapy of duodenal ulcer, and was in remission. During a follow-up one year later, endoscopy revealed gastric cancer, for which a proximal gastrectomy and vagotomy were performed. The patient continues to remain in remission for the groove pancreatitis. Our experience with the clinical course of this disease, in which treatment for duodenal ulcer was used effectively, offers new insights into the progression and therapy of groove pancreatitis.  相似文献   
59.
未研究发现,经热休克处理的大鼠注油酸后,肺组织损伤明显减轻,Western印迹分析显示热休克使大鼠肺组织中HSP70含量明显增多;Northern印迹分析证实此乃由于HSP70mRNA转录增加所致。说明热休克处理使肺组织HSP70基因表达增强;提示热休克反应对大鼠油酸肺的保护作用与肺组织细胞中HSP70基因表达增强及与HSP70增多有关。  相似文献   
60.
Nucleotide 6724 of the factor VIII gene harbors a polymorphism of low frequency. A report from Taiwan claimed that 97.9% of the 83 alleles examined were of the A nucleotide at this position, which is quite different to the data from Western populations. Furthermore, this nucleotide is the start of exon 25, located in juxtaposition to the splicing acceptor of intron 24. We wonder if the nucleotide change at this location might have any effect on the splicing process of pre-mRNA. Using genomic DNA with direct sequencing of the polymerase chain reaction-amplified intron 24/exon 25 junction site, we found that 59 of the 60 patient samples were of the GTG sequence at nucleotides 6724-6726. The polymorphism is similar between populations in Taiwan and Western countries. The sequence of intron 24 around the splicing acceptor was always TCCAACTCTATTGCCCTCAG (-20 to -1), except for one hemophiliac patient who had a mutation in which the absolute consensus AG doublet of the intron 24 splicing acceptor changed to the AA dinucleotide. Owing to the mutation, exon 24 was erroneously spliced to exon 26, and exon 25 was skipped. This finding further testifies to the importance of the invariant AG dinucleotide in the example of the factor VIII gene.  相似文献   
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