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991.
New insights into thyroid stem cells. 总被引:1,自引:0,他引:1
Reigh-Yi Lin 《Thyroid》2007,17(10):1019-1023
Stem cells exhibit an extraordinary ability for self-renewal. They also give rise to many specialized cells. The potential of stem cells in regenerative medicine, developmental biology, and drug discovery has been well documented. Although advances in stem cell science have raised broad ethical concerns, it is clear that stem cell technology has revolutionized our thinking in modern biology and medicine and provided the basis for understanding many of the mechanisms controlling basic biological processes and disease mechanisms. This review details the nascent field of thyroid stem cell research, exploring the current status of thyroid stem cell differentiation from the perspectives of both developmental biology and cell replacement therapy. It highlights successes to date in the generation of thyroid follicular cells from embryonic stem cells in the laboratory and the identification and characterization of adult stem cells from human thyroid glands and thyroid cancers. Finally, it outlines future challenges with a focus on potential stem cell therapy for thyroid patients. 相似文献
992.
关节镜下人工韧带重建前交叉韧带的临床初步体会 总被引:6,自引:0,他引:6
目的探讨关节镜下应用LARS人工韧带重建前交叉韧带的可行性及近期疗效. 方法用法国产LARS人工韧带对16例前交叉韧带(anterior cruciate ligament,ACL)损伤行关节镜下ACL重建术.等距点钻胫骨、股骨骨道,将肌腱拉入骨道,韧带游离部分位于关节腔内,拉紧后2枚螺钉固定韧带,合并损伤同期处理. 结果手术时间51~86 min,平均64 min.术后无滑膜炎、韧带断裂、活动明显受限等并发症.16例均随访1.5~6个月,平均3.8月.按照IKDC评分标准:术前C级6例,D级10例;术后A级6例,B级9例, C级1例(χ2=6.264,P<0.05).Lysholm膝关节功能评分术前36~76分,(63.7±7.3)分;术后86~97分,(94.8±9.6)分(t=10.356,P<0.05). 结论关节镜下LARS人工韧带重建ACL,操作简便,可使膝关节获得即时稳定性,早期康复锻炼,最大限度的防止关节功能受限,近期疗效满意. 相似文献
993.
放射性125I粒子组织间植入或联合放化疗治疗复发直肠癌 总被引:5,自引:1,他引:4
目的探讨超声或CT引导下放射性125I粒子组织间植入治疗复发直肠癌的技术可行性、近期疗效和副反应.方法 15例直肠癌术后盆腔复发患者,女4例,男11例.硬膜外麻醉,2例经阴道超声引导,13例CT引导,行放射性125I粒子植入术.肿瘤匹配周边剂量为90~110 Gy,每颗粒子活度为0.50~0.70 mCi,植入33~70颗.术后24~48 h拍胸、盆腔X线片了解粒子是否发生移位.术后6例加三维适形放疗,4~6野/次,200~300 cGy/次,5次/周,总剂量为4 500~5 000 cGy,间隔4周.2例粒子治疗后加草酸铂、5-氟尿嘧啶和四氢叶酸化疗1个周期,随访3~15个月,根据CT扫描结果判断肿瘤大小. 结果术后平均7天疼痛缓解,其中12例完全缓解,2例部分缓解,1例无变化,有效率93%(14/15).9例肿瘤完全缓解,2例部分缓解,4例局部进展,局部控制率73%(11/15).2例术后6个月和12个月时死于肺转移.1例1颗粒子移位至盆壁,随访12个月无症状.无治疗相关并发症和副作用发生. 结论经超声或CT引导放射性125I粒子植入治疗复发直肠癌具有安全、微创、并发症发生率低和疗效肯定等优势,粒子治疗后应配合外放疗和全身化疗,有望进一步提高疗效. 相似文献
994.
OBJECTIVE: To study the cellular expression of CD45RO, CD20, CD68 and proliferating cell nuclear antigen (PCNA) in nasal polyps. METHODS: Nasal polyp tissues from 50 patients were evaluated for cellular expression of CD45RO, CD20, CD68 and PCNA using immunohistochemistry SP by counting the average number in 5 chosen high-power fields, Histopathological observations were combined with HE. Analyses were performed on SPSS10.0. RESULTS: CD68+ cells were expressed more in nasal polyps dominated by eosinophils than by neutrophils(P < 0.05). There was no difference between CD45RO and CD20, but both of them had negative correlation(P = 0.05). Significant correlation was found between CD68+ cells and eosinophils or PCNA positive cells on epithelium. PCNA positive cells on epithelium had significant correlation on fibroblast (P < 0.05). CONCLUSION: Inflammatory cell infiltration (eosinophilia CD45RO, CD20, CD68) and cell proliferating in epithelium cells, glandular cell and fibroblast are strongly correlated with formation of nasal polyps. The nasal polyps are not only characteristic of eosinophilia but also by lymphocytes dominated by CD45RO and CD68 positive cells. CD68 may be stem cell of nasal polyp. 相似文献
995.
OBJECTIVE: To investigate the clinicopathlogical significance of cyclinE, cyclinD1, P21WAF1/CIP1 and P27KIP1 expression in squamous cell carcinoma of maxillary sinus. METHODS: The expression of cyclinE, cyclinD1, P21WAF1/CIP1 and P27KIP1 was examined by the method of immunohistochemistry in inflammatory mucosa of maxillary sinus(10), inverting papilloma of maxillary sinus(20) and squamous cell carcinoma of maxillary sinus (50). RESULTS: (1) In inflammatory mucosa, inverting papilloma and squamous cell carcinoma, the positive immunostaining rates of cyclinD1 protein were 10.0%, 25.0%, 48.0% respectively (P < 0.05); cyclinE protein was 20.0%, 35.0%, 58.0% respectively (P < 0.05); P21WAF1/CIP1 protein was 80.0%, 65.0%, 40.0% respectively (P < 0.05) and P27KIP1 protein was 70.0%, 75.0%, 40.0% respectively (P < 0.05). (2) There was no significance between the clinical type, T stage and clinical stage of carcinoma of maxillary sinus and the expression of cyclinD1, cyclinE, P21WAF1/CIP1 and P27KIP1 (P > 0.05). (3) P21WAF1/CIP1 positive expression in highly, moderately and poorly differtiated carcinomas were 73.2% (11/15), 58.9% (11/19), 25.0% (4/16) respectively (P < 0.05). CONCLUSION: (1) With the development of the lesion, the positive immunostaining rate of cyclinE and cyclinD1 protein increases, while the rate of P21WAF1/CIP1 and P27KIP1 protein decreases. (2) P21WAF1/CIP1 expression is associated with tumour cell differentiation. (3) The mutual mechenism of cell cycle regulators plays an important role in the squamous cell carcinoma of maxillary sinus. The quantity and the frequency of four kinds of gene expression increase with the progression of maxillary sinus carcinogenesis. 相似文献
996.
997.
998.
目的分析肺癌骨转移引起腰腿痛症状导致误诊的原因及教训。方法对1例误诊为腰椎间盘突出症、腰臀部慢性软组织损害的肺癌骨转移致腰腿痛患者的诊疗过程结合文献进行综合分析。结果肺癌骨转移所致腰腿麻痛症状是因受累椎体发生溶骨性破坏或楔形变,对应椎管位置狭窄,肿瘤侵犯骨皮质或软组织肿块压迫刺激脊髓和神经根而引起,本病误诊的主要原因是病史询问不详,查体简单、粗疏,未做针对性强的影像学检查。结论仔细询问病史,认真查体,与早期行针对性强的影像学检查相结合,可有效降低误诊率。 相似文献
999.
Feng-Yuan Liu Chien-Yu Lin Joseph T Chang Shu-Hang Ng Shy-Chyi Chin Hung-Ming Wang Chun-Ta Liao Sheng-Chieh Chan Tzu-Chen Yen 《Journal of nuclear medicine》2007,48(10):1614-1619
Conventional work-up (CWU) with chest radiography, abdominal ultrasonography, and skeletal scintigraphy has limited value in M staging of nonkeratinizing nasopharyngeal carcinoma (NPC). Our aim was to evaluate whether (18)F-FDG PET could replace CWU by comparing their diagnostic efficacies. METHODS: Patients with histologically proven nonkeratinizing NPC and no prior treatment were prospectively enrolled. All study participants underwent CWU and (18)F-FDG PET for primary M staging. Distant metastasis was considered to be present if there was any reliable evidence identified within 1 y after diagnosis. The comparative diagnostic efficacies of (18)F-FDG PET, CWU, and the combination of (18)F-FDG PET and CWU (PET+CWU) were evaluated using the areas under the receiver-operating-characteristic (ROC) curves. RESULTS: Sixty-one (20.3%) of 300 eligible patients were found to have distant metastases. On a patient-based analysis, (18)F-FDG PET was found to be more effective than CWU (P < 0.001), whereas it was equally effective with PET+CWU (P = 0.130). On region-based analyses, (18)F-FDG PET was more effective than skeletal scintigraphy and chest radiography for detecting bone metastases (P < 0.001) and chest metastases (P < 0.001), respectively. (18)F-FDG PET and abdominal ultrasound were equally effective for detecting hepatic metastases (P = 0.127). On region-based analyses, the combination of (18)F-FDG PET and CWU did not yield any noticeable increase in diagnostic efficacy. CONCLUSION: (18)F-FDG PET can replace CWU in primary M staging of nonkeratinizing NPC. 相似文献
1000.
J C Shih T L Ko M C Lin M K Shyu C N Lee F J Hsieh 《Ultrasound in obstetrics & gynecology》2004,24(2):202-206
The relationship of large and vascularized chorioangiomas to adverse pregnancy outcome is well recognized. We present a patient with a large placental tumor and signs of impending fetal cardiac failure. The angioarchitecture of the tumor depicted by three-dimensional (3D) power Doppler ultrasound enabled us to accurately diagnose a placental chorioangioma. During the follow-up period, quantitative flow data obtained using 3D power Doppler indicated altered hemodynamics in the tumor and concomitant improvement in the condition of the fetus, enabling us to manage the mother conservatively. Spontaneous delivery occurred at 38 weeks without any complications. This report demonstrates the potential value of 3D power Doppler in prenatal diagnosis and monitoring of pregnancies complicated by large, vascularized chorioangioma. 相似文献