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961.
962.
胃癌细胞肿瘤坏死因子受体的研究 总被引:2,自引:0,他引:2
目的 探讨人胃癌细胞肿瘤坏死因子受体 ( TNFR)的数目与胃癌细胞分化程度以及与肿瘤坏死因子突变体 ( TNF- m)细胞毒效应之间的关系。方法 以12 5I- TNF- m为配体 ,用放射配体结合分析法 ,检测了高、中、低不同分化程度的体外培养胃癌细胞 ( MKN2 8、SGC790 1、MKN4 5)的 TNFR,同时用 MTT比色法研究了 TNF- m对三株胃癌细胞的细胞毒效应。结果 三株胃癌细胞 TNFR数目分别为每细胞 9.8× 10 -12 nmol、5.6× 10 -12 nmol、3.2× 10 -12 nmol,三者之间比较 ,TNFR数目差异有显著性 ( P<0 .0 5)。解离常数基本一致 ,同一温度时三株胃癌细胞 TNF- m的内化率几乎相等 ,且呈温度依赖关系。TNFR的半衰期大约为 90分钟 ,胞膜与胞浆 TNFR数目之比约为 1∶ 2 ,TNF- m对三株胃癌细胞的最大杀伤率分别为 86%、60 %、34 % ,差异有显著性 ( P<0 .0 5) ,且 39℃时的杀伤率高于37℃时的杀伤率。结论 胃癌细胞表面 TNFR数目与胃癌分化程度相关。 TNF- m的细胞毒效应与TNF数目及 TNF- m的内化量有关。 相似文献
963.
喉癌中13号染色体杂合性丢失研究 总被引:1,自引:0,他引:1
目的 为初步限定喉癌中 13号染色体抑癌基因的缺失区域和为发现及定位抑癌基因提供线索和依据。方法 应用聚合酶链反应 ( PCR) ,筛查了 58例喉癌 (包括 3例原位癌 )组织中染色体13q上 D13S765( 13q13) ,RB1.2 0 ( 13q14.2 ) ,D13S133( 13q14.3) ,D13S318( 13q2 1) 4个座位微卫星多态标记的杂合性丢失。结果 3例原位癌中无一例发生 13q的杂合性丢失 ,55例浸润癌中在 13q一个以上座位出现杂合性丢失的频率为 4 5% ( 2 4 / 53) ,D13S765座位的杂合性丢失的频率最高 ,为 52 %( 2 2 / 4 2 )。结论 喉癌组织中染色体 13q缺失区域在 D13S765( 13q13)座位附近 ,RB1的近端 ,即在D13S765座位附近存在着与喉癌发生发展密切相关的抑癌基因 ,可能包括 RB1基因 ,它的失活与浸润期喉癌发生发展密切相关。 相似文献
964.
p53反义RNA对肠癌细胞恶性表型的抑制作用 总被引:8,自引:0,他引:8
研究p53反义RNA对大肠癌细胞中突变型p53致癌性的抑制效应,为肿瘤基因治疗提供新思路。方法2.1kb的人p53全长cDNA反向插入哺乳动物表达载体pREP9,得到p53反义RNA表达载体pREP9-p53(AS),并将其导入人肠癌细胞株SW1116(内源性突变型p53),采用MTT和FCM方法测定pREP9-p53(AS)表达的p53反义RNA对SW1116细胞生长的影响。结果带有pREP9-p53(AS)的SW1116细胞,与对照组SW1116细胞和带pREP9空载体的SW1116细胞相比,由于p53反义RNA的表达,其增殖速度显著下降,FCM的结果也证明带pREP9-p53(AS)的细胞部分受阻于G0/1期,而带pREP9空载体的细胞则无明显变化。结论p53反义RNA可以有效地抑制大肠癌细胞中突变型p53的致癌性,可用于实验性肿瘤基因治疗研究 相似文献
965.
Sakuragi T Fujiwara K Akashi-Tanaka S Tsuda H Fukutomi T 《Breast cancer (Tokyo, Japan)》1997,4(1):53-56
Dermatofibrosarcoma protuberans (DFSP) is a slow-growing but locally aggressive, fibrous tumor that has a high rate of local
recurrence after surgical resection. This tumor occurs most commonly in the trunk and proximal extremities. In this report
we present a case of dermatofibrosarcoma protuberans in the skin over the breast which was re-excised after pathological diagnosis,
considering cosmetic aspects. Only three other cases of dermatofibrosarcoma protuberans of the anterior chest wall have been
encountered in our hospital, and all of these cases were male. The presence of this tumor in the skin over the breast appears
to be rare in females. Careful complete resection is recommended for this type of tumor. 相似文献
966.
We report a case of angiosarcoma of the breast and the autopsy findings. The patient was a 35-year-old premenopausal woman
who complained of a tumor in her left breast. We found a tumor measuring 55 mm in diameter in the lower external quadrant.
The tumor was elastic and soft, smooth surfaced, well-defined and mobile. Dimpling sign or change of skin color were not observed.
Clinically it was diagnosed as phyllodes tumor, but tumorectomy revealed primary angiosarcoma of the breast. Further extended
surgery was recommended, but the patient refused additional therapy. Histological findings revealed a free surgical margin
and neither lymph node metastasis nor distant metastasis were clinically observed. Seven months later, local recurrence in
the same breast was recognized and finally radical mastectomy was carried out. Histological findings showed recurrence of
angiosarcoma in the left breast but lymph node metastasis was not detected. Two months after mastectomy, metastases to the
cervical and thoracic vertebrae were observed and radiation therapy was performed. Sixteen months from onset, she died due
to multi-organ failure as general metastases of angiosarcoma. At autopsy, metastases to many organs including the digestive
system were observed. The incidence of primary angiosarcoma of the breast is low but its prognosis is poor. This case emphasized
the difficulties in clinical diagnosis and treatment for the angiosarcoma of the breast. 相似文献
967.
Cytogenetic analysis was performed on 7 lowgrade astrocytomas, 10 anaplastic astrocytomas, and 14 glioblastomas. Abnormal
chromosome numbers were noted in all cases of high-grade astrocytomas but were rarely noted in low-grade astrocytomas (28%).
The most consistent changes in high-grade astrocytomas were complete loss of chromosome 10 (61%), gain of chromosome 7 (56%),
and loss of chromosome 17 (28%). Certain structural abnormalities, such as marker chromosomes and double minutes (33%), and
the deletion and translocation of chromosomes 1 (33%) and 17 (17%), were also noted. These results indicate that changes in
the number and/or structure of chromosomes with related inactivation of tumor suppressor gene or oncogene activation might
play a critical role in the formation and anaplastic progression of astrocytic tumors. 相似文献
968.
Dr. Martin Scholz Stefanie Märzheuser-Brands Joachim Gottschalk Johannes C. Böck Wolfgang R. Lanksch 《Neurosurgical review》1994,17(1):89-93
The authors add to the literature a case report of a 32-year-old man with an intramedullary epidermoid cyst at the level of D 3/4, that was successfully operated on. There are several previous reports in the literature, but only five of these include MRI studies. 相似文献
969.
The purpose of this investigation was to determine whether paraplegia induced by neoplastic cord compression affects the pharmacodynamics of phenobarbital general anesthesia or of pentylenetet-razol (PTZ)-induced convulsions. Paraplegic rats harboring a thora-columbar epidural tumor, or an identical hindlimb tumor mass, received an i.v. infusion of phenobarbital until the onset of anesthesia. At that point, the phenobarbital concentrations in the CSF and serum were measured. Similarly, PTZ was infused until the onset of maximal seizures. It was found that changes related to systemic tumor growth and newly developed paraplegia due to neoplastic spinal cord compression did not attenuate the pharmacodynamics of phenobarbital. However, sustained paraplegia of 4 days duration reduced CNS sensitivity to the hypnotic action of the barbiturate as evidenced by the higher cerebrospinal fluid phenobarbital concentration required to induce anesthesia (170 ± 31 vs 125 ± 20 mg/L; P < 0.05). On the other hand, sustained paraplegia did not affect brain threshold concentration for PTZ-induced seizures. 相似文献
970.
Harry T. Whelan Lucy H. Kras Kutlan Ozker Dawn Bajic Meic H. Schmidt Yu Liu Lisa Ann Trembath Fusun Uzum Glenn A. Meyer Annette D. Segura B. David Collier 《Journal of neuro-oncology》1994,22(1):7-13
The use of PHOTOFRIN for photodynamic therapy of human gliomas has been studied by i.v. administration and laser photosensitization. Defining the uptake of PHOTOFRIN in the patient's tumor in comparison with the surrounding normal brain tissue is highly desirable for patient selection and study ofin vivo kinetics. We utilized a non-invasive approach to the detection of PHOTOFRIN uptake in brain tumors with111In-oxine radiolabeled PHOTOFRIN and external imaging and quantitation using a gamma camera. Biodistribution of111In-labeled PHOTOFRIN in 13 organs was determined in four dogs and 15 mice with gliomas.99mTc-DTPA was used as a control for nonspecific uptake. The greatest concentration of111In-PHOTOFRIN in the brain tumor occurred at 24 hours post i.v. administration. The brain tumor PHOTOFRIN uptake was seven times greater than that of normal brain. The decreased blood background at 72 hours made this the optimum time for imaging. Specific tumor tissue uptake of111In-PHOTOFRIN occurred, well beyond that resulting from blood-brain-barrier (BBB) breakdown. 相似文献