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991.
免疫耐受在乙型病毒性肝炎慢性化进程中发挥重要作用已经被多数学者所认可,研究表明,在免疫耐受过程中,树突状细胞(dendritic cells,DC)发挥克隆清除、克隆无能、表达T细胞抑制因子、选择性激活辅助T细胞和诱导调节性T细胞(regulatory Tcells,Treg)尤其是CD4+CD25+Treg的产生等作用。而CD4+CD25+Treg主要以DC为作用靶点,影响其分化成熟,抑制DC向T细胞提呈抗原,并通过非特异性接触抑制T细胞活化,诱导免疫耐受。因此,DC和CD4+CD25+Treg在免疫耐受中相互作用、互为靶点,并发挥协同效应。  相似文献   
992.
AIM: To evaluate immunological protection of nitric oxide (NO) in hepatopulmonary syndrome and probable mechanisms of ischemia-reperfusion (IR) injury in rat liver transplantation.METHODS: Sixty-six healthy male Wistar rats were randomly divided into three groups (11 donor/recipient pairs). In group II, organ preservation solution was lactated Ringer’s solution with heparin 10  000/μL at 4 °C. In groups I and III, the preservation solution added, respectively, L-arginine or NG-L-arginine methyl ester (L-NAME) (1 mmol/L) based on group II, and recipients were injected with L-arginine or L-NAME (50 mg/kg) in the anhepatic phase. Grafted livers in each group were stored for 6 h and implanted into recipients. Five rats were used for observation of postoperative survival in each group. The other six rats in each group were used to obtain tissue samples, and executed at 3 h and 24 h after transplantation. The levels of alanine aminotransferase (ALT), tumor necrosis factor (TNF)-α and NO metabolites (NOx) were detected, and expression of NO synthase, TNF-α and intercellular adhesion molecule 1 (ICAM-1) was examined by triphosphopyridine nucleotide diaphorase histochemical and immunohistochemical staining.RESULTS: By supplementing L-arginine to strengthen the NO pathway, a high survival rate was achieved and hepatic function was improved. One-week survival rate of grafted liver recipients in group I was significantly increased (28.8 ± 36.6 d vs 4 ± 1.7 d, P < 0.01) as compared with groups II and III. Serum levels of ALT in group I were 2-7 times less than those in groups II and III (P < 0.01). The cyclic guanosine monophosphate (cGMP) levels in liver tissue and NOx in group I were 3-4 times higher than those of group II after 3 h and 24 h reperfusion, while in group III, they were significantly reduced as compared with those in group II (P < 0.01). The levels of TNF-α in group I were significantly lower than in group II after 3 h and 24 h reperfusion (P < 0.01), while being significantly higher in group III than group II (P < 0.01). Histopathology revealed more severe tissue damage in graft liver and lung tissues, and a more severe inflammatory response of the recipient after using NO synthase inhibitor, while the pathological damage to grafted liver and the recipient’s lung tissues was significantly reduced in group I after 3 h and 24 h reperfusion. A small amount of constitutive NO synthase (cNOS) was expressed in liver endothelial cells after 6 h cold storage, but there was no expression of inducible NO synthase (iNOS). Expression of cNOS was particularly significant in vascular endothelial cells and liver cells at 3 h and 24 h after reperfusion in group II, but expression of iNOS and ICAM-1 was low in group I. There was diffuse strong expression of ICAM-1 and TNF-α in group III at 3 h after reperfusion.CONCLUSION: The NO/cGMP pathway may be critical in successful organ transplantation, especially in treating hepatopulmonary syndrome during cold IR injury in rat orthotopic liver transplantation.  相似文献   
993.
目的 探讨高龄心房颤动(房颤)患者行导管消融治疗围术期有效而安全的抗凝方案.方法 选取射频消融治疗的高龄(>75岁)房颤患者15例(高龄组),术前服用华法林;同期<75岁射频消融治疗房颤患者15例(非高龄组),根据栓塞风险服用华法林或阿司匹林治疗.术中均用肝素抗凝;高龄组术后以低分子肝素过渡,第3天开始服用华法林,非高龄组术后从第1天开始华法林与低分子肝素重叠应用3d;院外两组服用华法林抗凝3个月.3个月后根据CHADS2评分服用阿司匹林或华法林治疗.门诊随访至少12个月,比较两组凝血酶原时间-国际标准化比值(PT-INR)、6个月内出血和栓塞事件发生率及术后3、6、12个月24 h动态心电图记录心律失常情况.结果 术前高龄组与非高龄组PT-INR值(1.58±0.32对1.37±0.44,P>0.05),术后INR达标天数[(11.73±3.29)d对(9.71±3.63)d,P>0.05];左心房内自发显影情况[3例(20.00%)对4例(26.67%),P>0.05];出血并发症(0对6.67%,P=0.05)、栓塞事件发生率(6.67%对0,P=0.05)差异无统计学意义.两组间术后3、6、12个月心律失常复发情况差异无统计学意义.结论 高龄房颤患者行导管消融治疗术前需严格抗凝并排除心房血栓;术中抗凝与常规用药相同;术后延迟加用华法林治疗同样安全有效.  相似文献   
994.
目的 评估莫雷西嗪治疗阵发性心房颤动(房颤)患者的有效性和不良反应以及其对房颤负荷的影响.方法 入选阵发性房颤患者212例,给莫雷西嗪单药干预,并随访观察治疗1、6、12个月后房颤的再发情况、负荷量和不良反应.结果 服用莫雷西嗪1、6、12个月房颤再发率仅34%、32%、35%;用药前与用药后1、6、12个月平均心率,最大心率和最小心率均无明显变化,房颤负荷均有明显下降,并未见死亡和恶性室性心律失常.结论 莫雷西嗪可以作为预防、治疗阵发性房颤发作的选择药物之一.  相似文献   
995.
AIM:To study the therapeutic efficacy of a new transnasal ileus tube advanced endoscopically for adhesive small bowel obstruction.METHODS:A total of 186 patients with adhesive small bowel obstruction treated from September 2007 to February 2011 were enrolled into this prospective randomized controlled study.The endoscopically advanced new ileus tube was used for gastrointestinal decompression in 96 patients and ordinary nasogastric tube(NGT) was used in 90 patients.The therapeutic efficacy was compared between the two groups.RESULTS:Compared with the NGT group,the ileus tube group experienced significantly shorter time for relief of clinical symptoms and improvement in the findings of abdominal radiograph(4.1 ± 2.3 d vs 8.5 ± 5.0 d) and laboratory tests(P 0.01).The overall effectiveness rate was up to 89.6% in the ileus tube group and 46.7% in the NGT group(P 0.01).And 10.4% of the patients in the ileus tube group and 53.3% of the NGT group underwent surgery.For recurrent adhesive bowel obstruction,ileus tube was also significantly more effective than NGT(95.8% vs 31.6%).In the ileus tube group,the drainage output on the first day and the length of hospital stay were significantly different depending on the treatment success or failure(P 0.05).The abdominal radiographic improvement was correlated with whether or not the patient underwent surgery.CONCLUSION:Ileus tube can be used for adhesive small bowel obstruction.Endoscopic placement of the ileus tube is convenient and worthy to be promoted despite the potential risks.  相似文献   
996.
997.
目的观察营养状况及营养支持治疗对COPD患者治疗及预后的重要性。方法 76例COPD住院患者随机分为营养支持组(A组)和常规对照组(B组),各38例,观察在住院期间临床总有效率,平均住院时间,营养状况,血清尿酸,肺功能变化。结果 A组临床总有效率明显高于B组;平均住院时间A组明显短于B组;营养状况、血清尿酸、肺功能A组明显优于B组。结论在常规治疗的基础上,应用营养支持治疗可以明显改善老年COPD患者营养状况、肺功能,提高临床疗效,减少住院天数。  相似文献   
998.
999.
Congenital adrenal hyperplasia (CAH) is a group of disorders affecting the adrenal steroid synthesis. The most common form, 21-hydroxylase deficiency (21-OHD), leads to decreased production of cortisol and aldosterone with increased androgen secretion. In classic CAH, glucocorticoid treatment can be life-saving and serves to bring the symptoms under control. However, the treatment challenge is to effectively control the excess androgen effect by using the lowest possible glucocorticoid dose. Previous studies suggested a relationship between ovarian cyst formation and adrenal androgen excess, but neonatal large ovarian cysts have been very rarely reported in newborns with CAH. Here, we present the unique case of a neonate with classical 21-OHD who underwent surgery for a giant (10x8x7 cm) unilateral solitary ovarian follicular cyst on the 2nd postnatal day. Hormonal evaluation of the patient revealed high-dose hook effect for serum testosterone levels for the first time by a two-site immunoradiometric assay. Possible mechanisms by which androgen excess may cause ovarian cyst formation are discussed.  相似文献   
1000.
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