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81.
Object A radiation dose of 40–50 Gy is able to produce a cure rate of more than 90% in intracranial pure germinoma. However, many attempts have been made to reduce the dose and volume of radiation without compromising the disease control rate because of the toxicity of irradiation. This retrospective study is intended to provide the physician with an appropriate therapeutic strategy. Materials and methods We reviewed a series of 10 recurrent germinomas among 117 germinomas diagnosed histologically or clinically between 1979 and 2002. These patients involved underwent three different treatment modalities; radiation alone (N = 71), chemotherapy alone (N = 9), and combined therapy (N = 37). The 10-year overall and relapse-free survival rates were 97 and 93% in the radiation alone group, 89 and 67% in the chemotherapy alone group, and 92 and 92% in the combined therapy group, respectively. As expected, both radiation therapy and combined therapy were effective in controlling the disease. Tumor recurrence was closely related to the volume of radiation but not to the dose of radiation. If the tumor bed and craniospinal axis were fully covered, the radiation dose might be reduced. Chemotherapy alone showed earlier recurrence and a higher tumor recurrence rate. In the case of combined therapy, chemotherapy was useful in reducing the radiation dose but revealed some toxicity (death of two patients). Conclusions The investigation of a possible further dose reduction seems worthwhile. Radiation therapy alone with a dose of less than 40 Gy should be compared with ongoing chemotherapeutic protocols combined with low-dose irradiation.  相似文献   
82.
肾上腺区神经节细胞瘤(附18例报告)   总被引:3,自引:0,他引:3  
目的较全面的了解神经节细胞瘤的临床特点及治疗方法。方法回顾性分析18例病理确诊的神经节细胞瘤患者临床表现、实验室检查、影像学检查和治疗效果。结果15例是无临床症状的影像学偶然发现病例,内分泌检查均在正常范围;另外3例以阵发性高血压为主要临床表现,其中1例尿儿茶酚胺升高,肾上腺髄质显像(MIBG)阳性。18例B型超声检查均为低回声;13例CT平扫见散在点状高密度影,12例CT增强扫描肿瘤周边强化明显。手术前诊断为嗜铬细胞瘤12例,神经节细胞瘤4例,肾上腺无功能腺瘤2例。18例行肿瘤切除,随访6个月~7年,高血压症状消失,2例肿瘤复发。结论肾上腺区神经节细胞瘤与肾上腺髄质肿瘤难以鉴别,综合各项影像学检查对诊断有较高的参考价值。手术治疗是唯一的有效方法。  相似文献   
83.
目的:探讨急诊外伤性胃肠穿孔的CT征象及诊断价值。方法:收集18例经手术证实的外伤性胃肠道穿孔的临床资料及CT征象,分析与总结胃肠道破裂穿孔CT扫描的各种有价值的表现。结果:18例外伤急诊患者中,胃、十二指肠、空回肠与结肠穿孔各1,2,12,3例,其中空回肠为多处破裂,CT主要征象为腹腔散在积液征、游离气腹征、肠系膜与肠壁增厚模糊征、造影剂外溢征。结论:CT扫描在外伤性胃肠道穿孔急诊患者的检查中有定性诊断价值,综合分析各种征象,会明显提高CT的诊断正确率。  相似文献   
84.
目的:探讨和研究治疗晚期面瘫的手术治疗,总结应用以足底内侧动静脉为蒂的(足母)展肌游离移植一期修复晚期面瘫40例效果和经验.方法:选取(足母)展肌为供肌,以足底内侧动静脉及其延续的胫后动静脉为血管蒂,以支配(足母)展肌神经及其延续的足底内侧神经和胫神经为神经蒂.(足母)展肌移植于患侧面部皮下,肌近断固定于口角,远端固定于耳前颧弓,血管神经蒂通过上唇皮下隧道与健侧面动静脉和面神经颊支吻合.结果:经随访一年以上,23例恢复了面部静态对称和理想的下面部随意和不随意运动;8例恢复了面部静态对称和部分下面部随意和不随意运动;9例仅恢复了面部静态对称.结论:(足母)展肌游离移植一期修复晚期面瘫具有疗效好、手术操作简便、肌肉大小适中、血管神经蒂走行位置恒定紧密伴行、血管神经蒂可切取较长、变跨面神经移植和肌肉移植的两期移植为一期移植等优点;而且,神经是血管化移植.  相似文献   
85.
A patient with skeletal Class III malocclusion was treated in 2 phases during the early permanent dentition. In phase 1, maxillary protraction was combined with rapid palatal expansion; in phase 2, fixed appliances were placed. The results were good posttreatment, and, 1 year later, a favorable growth tendency could be observed. This report shows that treatment for a patient with skeletal Class III malocclusion can be started in the early permanent dentition, with very good final results.  相似文献   
86.
Transforminggrowthfactor-β1(TGF-β1)is amultifunctionalpolypeptidethatregulatesanum-berofcellularprocesses,includingcellprolifera-tion,differentiation,apoptosis,migration,matrix synthesis,andtheimmuneresponse[1,2].Inchron-icrenaldiseases,TGF-β1isakeymediatorofex-tracellularmatrix(ECM)accumulation[3].Oneof thetargetrenalcellsforTGF-β1isglomerular mesangialcellsthatarecapableofproducingcom-ponentsofECM,suchascollagens,lamininand fibronectin[4,5].Recentstudiesindicatedthatinhi-bitionofT…  相似文献   
87.
88.
Transforming growth factor-β1 (TGF-β1) is known to be a potent growth inhibitor for many cell types, including most epithelial cells. In skin keratinocytes, TGF-β1 has been shown to inhibit growth and to rapidly reduce c-mycexpression. However, the molecular mechanism of TGF-β1 action on cell growth of cervical carcinoma has not yet been elucidated. We thus assessed the effect of TGF-β1 on the growth of cervical carcinoma cell lines. Two cervical squamous carcinoma cell lines, CUMC-3 and CUMC-6, were incubated with varying concentrations of TGF-β1, and growth inhibition was evaluated with tetrazolium-based colorimetric assay. After culture in TGF-β1 for 24 h, inhibition of growth was detected in a dose-dependent manner at concentrations of 0.1–10 ng/ml in both cell lines. This effect of TGF-β1 on cultured carcinoma cells was associated with apoptotic process including oligonucleosomal ladder DNA and apoptotic body formations. Northern blot analysis revealed c-mycmRNA expression was suppressed by 10 ng/ml of TGF-β1 following 3 h of treatment in both cell lines. Western blot analysis showed that the level of p27Kip1protein was increased after TGF-β1 treatment in both cell lines. These results suggest that the mechanisms by which TGF-β1 inhibits the growth of cervical carcinoma are complex and may include effects on down-regulation of c-mycgene, and overexpression of p27Kip1protein.  相似文献   
89.
Emphysematous cystitis is characterized by gas collection within the bladder wall and lumen. We report two cases of emphysematous cystitis of the urinary bladder in a 67-year-old and a 63-year-old women. They presented with bladder irritation symptoms such as dysuria, hematuria and frequency. Urinalysis showed pyuria. Cystoscopic examination revealed that bladder mucosa was studded with vesicles varying in size and arranged in clumps. CT scans of the pelvis showed mottled gas bubbles within the bladder. They were treated with antibiotics. Four days after the treatment, the symptoms subsided and plain abdominal film showed no evidence of gas shadows in the pelvic cavity.  相似文献   
90.
The determination of a unicellular or a multicellular origin of a tumor is an important due for understanding its etiology. To investigate this issue, we performed clonality assay of cervix cancer using polymerase chain reaction based on highly polymorphic locus of the androgen receptor gene, in which methylation of DNA correlates with inactivation of X chromosome. DNA samples were obtained from formalin-fixed, paraffin-embedded tissue of 20 invasive epidermoid carcinomas and 10 carcinoma in situ. Seven of ten carcinoma in situ, heterozygous for the androgen receptor locus, were monoclonal pattern. Among twenty invasive epidermoid carcinomas, eighteen of which showed heterozygous, twelve were monoclonal pattern and six were polyclonal pattern. We conclude that carcinoma in situ arises from a single cell. In invasive epidermoid carcinoma, most cases were monoclonal, although some cases were polyclonal. These suggest that invasive carcinoma of the cervix does not always arise from a single cell, but may arise from several cells with different mechanisms.  相似文献   
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