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51.
Purpose: To investigate the relationships between the axonal sprouting and target neurotization by central neurons after nerve heterocon-nection. Methods: Unilateral (right) vagal-hypoglossal nerve anastomosis (VHA) was performed in adult cats. Following 3-315 days postoperation (dpo), quantitative analyses and ultrastructural changes in the proximal portion of the vagal-hypoglossal heteroconnected nerve as well as the time course of neuronal regeneration were studied. Along with this, horseradish peroxidase (HRP) retrograde tracing technique was used to label the neurons of dorsal motor vagal nucleus (DMV) and nucleus ambiguus (NA) to ascertain if target neurotization was established. Results: The contralateral (left) intact vagus nerve proximal to the level of ansa cervicalis showed an average of 33 +/- 1 myelinated and 74 +/- 4 unmyelinated axons in 727 &mgr;m(2) sectional area of the nerve. In the heteroconnected nerve at the corresponding level just proximal to the anastomosis site, there was a marked increase in the number of small axons sprouting from the unmyelinated nerve fibers between 18 and 25 dpo. The number of these axonal sprouts appeared to decline at 32 dpo but its increase of 131 % was sustained until the late regeneration stage at 315 dpo when compared with the contralateral nerve serving as a control. The mean number of myelinated axons per area unit (727 &mgr;m(2)) was reduced to 18 at 3 dpo but was immediately restored to the normal range at 7 dpo. The retrograde labelling of neurons in both the DMV and NA was first detected at 22 dpo and was progressively increased peaking by about 67 dpo. Conclusions: We conclude that compared with the unmyelinated axons, the myelinated axons may acquire a superior interaction with the new target. Furthermore, the postoperative neurotization of tongue muscles may initiate and facilitate the retraction of the redundant axonal sprouts. 相似文献
52.
K Kian Ang Jonathan Harris Adam S Garden Andy Trotti Christopher U Jones Luis Carrascosa Jonathan D Cheng Sharon S Spencer Arlene Forastiere Randal S Weber 《Journal of clinical oncology》2005,23(13):3008-3015
PURPOSE: To investigate the feasibility of combining concomitant boost accelerated radiation regimen (AFX-C) with cisplatin and to assess its toxicity and the relapse pattern and survival in patients with advanced head and neck carcinoma (HNC). PATIENTS AND METHODS: Between April and November of 2000, 84 patients with stage III to IV HNC who met the eligibility criteria were enrolled; 76 of these patients were analyzable. Radiation consisted of 72 Gy in 42 fractions over 6 weeks (daily for 3.5 weeks, then twice a day for 2.5 weeks). Cisplatin dose was 100 mg/m(2) on days 1 and 22. Tumor and clinical status were assessed, and acute late toxicities were graded. RESULTS: Sixty-five patients (86%) received both radiation and chemotherapy per protocol or with minor variations. The estimated 2-year locoregional relapse and distant metastasis rates were 34.7% and 16.1%, respectively. The estimated 2-year overall survival and disease-free survival rates were 71.6% and 53.5%, respectively. Three patients (4%) died of complications, 19 patients (25%) had acute grade 4 toxicity, and 49 patients (64%) had acute grade 3 toxicity. The 2-year cumulative incidence of late grade 3 to 5 toxicities was 51.3%. CONCLUSION: These data showed that it was feasible to combine AFX-C with cisplatin. The compliance to therapy was high, and the locoregional control and survival rates achieved compared favorably with AFX-C alone or other concurrent chemoradiation regimens tested by the Radiation Therapy Oncology Group. A phase III trial comparing AFX-C plus cisplatin against standard radiation plus cisplatin is ongoing to determine whether the use of AFX-C in the concurrent chemoradiation setting further improves outcome. 相似文献
53.
Anna van Rhenen Nicole Feller Angèle Kelder August H Westra Elwin Rombouts Sonja Zweegman Marjolein A van der Pol Quinten Waisfisz Gert J Ossenkoppele Gerrit Jan Schuurhuis 《Clinical cancer research》2005,11(18):6520-6527
PURPOSE: In CD34-positive acute myeloid leukemia (AML), the leukemia-initiating event originates from the CD34(+)CD38(-) stem cell compartment. Survival of these cells after chemotherapy may lead to minimal residual disease (MRD) and subsequently to relapse. Therefore, the prognostic impact of stem cell frequency in CD34-positive AML was investigated. EXPERIMENTAL DESIGN: First, the leukemogenic potential of unpurified CD34(+)CD38(-) cells, present among other cells, was investigated in vivo using nonobese diabetic/severe combined immunodeficient mice transplantation experiments. Second, we analyzed whether the CD34(+)CD38(-) compartment at diagnosis correlates with MRD frequency after chemotherapy and clinical outcome in 92 AML patients. RESULTS: In vivo data showed that engraftment of AML blasts in nonobese diabetic/severe combined immunodeficient mice directly correlated with stem cell frequency of the graft. In patients, a high percentage of CD34(+)CD38(-) stem cells at diagnosis significantly correlated with a high MRD frequency, especially after the third course of chemotherapy. Also, it directly correlated with poor survival. In contrast, total CD34(+) percentage showed no such correlations. CONCLUSIONS: Both in vivo data, as well as the correlation studies, show that AML stem cell frequency at diagnosis offers a new prognostic factor. From our data, it is tempting to hypothesize that a large CD34(+)CD38(-) population at diagnosis reflects a higher percentage of chemotherapy-resistant cells that will lead to the outgrowth of MRD, thereby affecting clinical outcome. Ultimately, future therapies should be directed toward malignant stem cells. 相似文献
54.
目的 考察复方肝素口服结肠靶向胶囊对大鼠溃疡性结肠炎(ulcerative colitis, UC)的治疗作用。方法 将大鼠随机分为模型组,正常对照组,阳性对照组,辅料对照组,复方肝素高、低剂量组共6组。其中除正常对照组外,其余5组均采用三硝基苯磺酸造模。连续灌胃给药12 d后,从组织损伤评分、髓过氧化物酶(myeloperioxidase, MPO)活性、肠道微生态的变化3方面对复方制剂的药效进行考察。结果 与模型组相比,复方肝素高剂量组结肠部位炎性损伤明显好转(P<0.01),MPO水平明显降低(P<0.01),肠道有益菌显著增加,有害菌明显降低。结论 复方肝素口服结肠靶向制剂对大鼠溃疡性结肠炎有较好的抗炎及改善肠道微生态的作用。 相似文献
55.
目的评价深板层角膜移植术治疗某些角膜疾病的临床疗效。方法回顾性分析我院16例(16眼)罹患角膜疾病但内皮细胞功能正常而行深板层角膜移植者,对所有病例随访6月-2年,观察术后视力、角膜移植片的透明性、角膜上皮完整性及术中术后并发症的情况。结果术后有7眼最佳矫正视力达0.4或0.4以上,5眼达0.1~0.3,4眼达0.05~0.1。角膜移植片透明者9眼,半透明者7眼。主要并发症为术中后弹力层微穿孔6眼,其中3眼术后形成植片轻度水肿,角膜层间少量积液;持续性上皮缺损2眼;真菌性角膜溃疡复发1眼,移植排斥反应1眼,经积极治疗,并发症得到控制,取得良好疗效。结论深板层角膜移植术治疗内皮功能正常的角膜疾病疗效确切,严格掌握手术适应证、提高手术技巧是提高手术成功率的关键。 相似文献
56.
57.
Ikram Hussain Saba Ishrat Veeraraghavan Meyyur Aravamudan Shahab R. Khan Babu P. Mohan Rahul Lohan Muhammad Bilal Abid Tiing Leong Ang 《Medicine》2022,101(17)
Background:Mesenteric panniculitis (MP) is a non-specific, localized inflammation at the mesentery of small intestines which often gets detected on computed tomography. An association with malignant neoplasms remains unclear. We performed a systematic review and meta-analysis to examine the association of malignancy with MP.Methods:MEDLINE, EMBASE, Web of Science, and Cochrane databases were searched for articles published from inception to 2020 that evaluated the association of malignant neoplasms with MP in comparison with control groups. Using random-effects method, a summary odds ratio (OR) estimate with 95% confidence intervals for malignant neoplasms in MP was estimated.Results:Four case-control studies reporting data on 415 MP patients against 1132 matched-controls met inclusion criteria and were analyzed. The pooled OR for finding a malignant neoplasm in patients with MP was 0.907 (95% CI: 0.688–1.196; P = .489). The heterogeneity was mild and non-significant. Also, there was no heightened risk of any specific type of malignancy with MP. Three more case-series with unmatched-control groups (MP: 282, unmatched-controls: 17,691) were included in a separate analysis where the pooled OR of finding a malignant neoplasm was 2.963 (95% CI: 1.434–6.121; P = .003). There was substantial heterogeneity in this group.Conclusion:This meta-analysis of matched controlled studies proves absence of any significant association of malignant neoplasms with MP. Our study also demonstrates that the putative association of malignancy with MP is mainly driven by uncontrolled studies or case-series. 相似文献
58.
目的在3.0T MRI检查仪上分析前列腺癌的表观扩散系数的变化,以病理结果作对照,探讨常规MRI、DWI两种成像方法及其联合应用对前列腺癌进行定性诊断的价值。方法收集28例前列腺癌(PCa)及20例前列腺增生(BPH)患者资料;在DWI上观察病灶的信号并进行ADC值测量,通过受试者操作特性曲线(ROC)评估ADC值对PCa的诊断效能,比较常规MRI单独应用及和ADC值二者联合应用对前列腺癌的诊断价值。结果 PCa平均ADC值为(0.78±0.025)×10-3,BPH平均ADC值为(1.59±0.045)×10-3。PCa与BPH的ADC值存在明显差异(P<0.05),根据ADC值诊断PCa的最佳诊断域值为1.182×10-3,此诊断域值敏感度为85.1%,特异性为96.4%。诊断效能:常规MRI诊断PCa的敏感度为82.14%,特异性为80.00%,准确度为81.25%。MRI+DWI诊断PCa的敏感度达92.85%,特异性为85%,准确度为89.58%。结论联合应用常规MRI和DWI的诊断效能优于单独应用常规MRI,3.0T MRI结合DWI有助于前列腺癌的早期诊断及鉴别诊断。 相似文献
59.
壁虎鲜品和炮制品抗肿瘤活性比较研究 总被引:4,自引:0,他引:4
目的:比较中药壁虎鲜品与炮制品对小鼠H22肝癌细胞体内外生长抑制作用的强弱。方法:体外试验采用MTT法,检测壁虎提取液冻干粉对H22细胞的增殖抑制情况;体内试验采用小鼠肝癌H22移植瘤法,比较对实体肿瘤的抑制作用,并检测药物对小鼠胸腺指数及脾指数的影响。结果:在体外试验中,壁虎鲜品和炮制品对H22细胞的半数抑制率IC50分别为8.53、6.42 mg/ml;体内试验,鲜品和炮制品最大抑瘤率分别为53.0%和47.4%。炮制品各组的胸腺指数和脾指数均高于环磷酰胺(CTX)阳性对照组,鲜壁虎的中、高剂量组胸腺指数和低剂量组脾指数较阳性对照组高。结论:鲜品与炮制品均有抗肿瘤作用,但二者活性差异不显著;炮制品对胸腺和脾脏有生长刺激作用。 相似文献
60.
Early side effects of radiation therapy are generally the result of mitotic-linked cell death in rapidly renewing tissues and secondary impaired tissue function. Various types of acute normal tissue reactions are briefly summarized in this article. In general, with conventionally fractionated radiation treatment, the acute normal tissue reactions are within acceptable limits. However, new radiotherapy strategies, such as hyperfractionation and accelerated fractionation, induce more severe acute toxicity. Particularly, with most altered fractionation schedules, the mucosal reaction of the upper aerodigestive tract is elevated to the upper limit of tolerance. Early mucosal reactions may also become dose limiting when radiation is combined with chemotherapy as, for instance, for the treatment of head and neck cancer or pelvic neoplasms. Bone marrow is the critical organ for combination of chemotherapy and wide field irradiation. There is an increasing body of evidence that iatrogenic acute normal tissue toxicity has become a major obstacle for treatment intensification for a variety of cancers. Therefore, effective measures to ameliorate these side effects are essential for further development of cancer therapy. Methods to reduce the severity of acute toxicity are being investigated. 相似文献