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71.
在制备了两个Cell Ⅰ-Hep Ⅱ 双结构域重组FN多肽(CH50和CH56)的基础上,研究其抑制肿瘤细胞浸润能力的作用。两个多肽的结构差异是CH50中删除了Cell I和HepⅡ之间的Ⅲ-11和ED-A结构顺序。CH50(ED_(50)为30.2 nmol/L)结合细胞的能力略高于CH56(ED_(50)为45.4 nmol/L)。两种多肽均可显著抑制黑色素瘤B16/F1细胞结合层粘素的能力,抑制作用相同。在体内肿瘤浸润抑制试验中,两种多肽均可显著抑制癌细胞浸润能力,使肺转移结节数降低80%左右。结果提示:Ⅲ-11和ED-A结构顺序对Cell Ⅰ-Hep Ⅱ 双结构域多肽结合细胞的能力有一定的影响,但删除Ⅲ-11和ED-A不是重组多肽抑制肿瘤转移的决定因素,Cell I和Hep Ⅱ 这两个结构域单独连接在一起是其抑制肿瘤细胞转移的结构基础。 相似文献
72.
高转移小鼠肺癌株细胞导入人基因组DNA后的转移表型抑制 总被引:2,自引:0,他引:2
目的 探讨从正常人细胞基因组DNA中寻找、分离并鉴定肿瘤转移抑制基因或相应DNA序列的新途径。方法 采用体内转移灶体外再培养再硬琼脂集落克隆化筛选,获体内90%以上高转移率小鼠肺腺癌LM2细胞株;使用磷酸钙共沉淀DNA转染技术,将正常细胞人基因组DNA随机片段,导入高转移小鼠肺癌细胞株LM2后,使用有限稀释法克隆化其中形态扁平的回复突变株。为证实细胞确实含有外源人DNA序列,设计人特异性Alu引物 相似文献
73.
Xianghua Zhang Fumio Tsukuda Norihito Yamamoto Ikumasa Takenaka 《International journal of urology》1997,4(5):519-521
Brain metastases from prostate cancer are rare in postmortem examinations, and even rarer in clinical series. We report an unusual case of brain metastasis from prostate cancer confirmed by antemortem diagnosis in a 72-year-old man. The metastatic brain tumor was surgically resected and the patient was kept stable for more than 19 months after diagnosis of the brain metastasis. 相似文献
74.
The clinical aspects of peritonitis and catheter infections were reviewed in 64 children on continuous ambulatory peritoneal
dialysis living in Saudi Arabia over a period of 6 years. Peritonitis occurred in 41 children (64%). The mean time from starting
dialysis to the first episode of peritonitis was 7.2 months. The incidence of peritonitis was 1 episode in 9 treatment months.
Gram-negative organisms were responsible for the majority of episodes (42%), followed by Gram-positive organisms (20%), and
Candida albicans (6%); 32% were culture negative. Recurrent peritonitis was present in 20 cases. Catheter was replaced in 24 patients: 44%
due to recurrent peritonitis. Peritoneal membrane loss occurred in 7 patients, 3 had Candida peritonitis and 3 had recurrent peritonitis due to Pseudomonas. The mortality rate was 4.6% but none of the deaths were related to peritonitis or dialysis.
Received August 23, 1995; received in revised form October 2, 1996; accepted October 18, 1996 相似文献
75.
目的:探讨乌苯美司对小鼠药物动力学及与实验性肿瘤转移治疗活性间的关系。方法:用放射免疫法测定小鼠在不同给药途径下的乌苯美司血清药物动力学及观察乌苯美司对黑色素瘤肺转移模型的治疗活性。结果:乌苯美司iv的T12较短,初始血药浓度较高。iv和im给药后的曲线下面积较大;po及ip则较小。不同给药途径对实验性肿瘤转移均有治疗作用。结论:乌苯美司的血清T12较短,其治疗活性取决于冲击和高剂量的给药方式。 相似文献
76.
Tatsuya Nomura Tokihiro Yoshikawa Hideo Kato Keiya Nikkuni Koichi Sasaki Yoshio Shirai Katsuyoshi Hatakeyama 《Surgery today》1997,27(4):334-336
A case of early gastric cancer, limited to submucosal layer, which was manifested as cerebral metastasis is presented herein. A 47-year-old man was admitted to Nagaoka Chuo General Hospital with convulsions and a disturbance in consciousness, where a computed tomography (CT) scan revealed a cerebral tumor in the left temporal lobe. The resected tumor was identified as a metastatic adenocarcinoma. Further investigation revealed gastric cancer involving the posterior wall of the cardia. At laparotomy, multiple and small metastases of the liver and a jejunal metastasis were found, and a palliative total gastrectomy was performed. The surgical specimen revealed a protruding, poorly differentiated medullary adenocarcinoma, with invasion of the submucosal layer. The patient died 4 months after undergoing the laparotomy. This case report is presented to make clinicians aware of the possibility that early gastric cancers may present as brain metastasis. 相似文献
77.
The purpose of this study was to evaluate the ability of MRI to identify a primary site of malignancy in the breast of patients who present clinically with ipsilateral lymph nodes containing metastatic carcinoma but whose physical and mammographic examination are negative. MRI of the breast was performed on four patients using a variety of imaging parameters, all with and without gadolinium contrast. All patients had biopsy-proven adenocarcinoma of the ipsilateral axilla, with negative physical and mammographic examinations. Foci of enhancement assessed visually on precontrast and postcontrast scans (n = 1) and on substraction studies (n = 3) were considered suspicious under the clinical circumstances defined for this study. Lesions identified on MRI were re-identified on ultrasound examination and either preoperative localization for excisional biopsy or tissue sampling was performed. Surgery was performed and histopathologic correlation was obtained in all cases. Primary sites of breast carcinoma were identified in all four patients, with multiple sites of malignancy identified in three of four patients. Breast conservation therapy was made possible for three of four patients based on the results of the MRI study showing sites of malignancy and no features of cancer elsewhere in the breast. Follow-up data of 1, 2, and 5 years of these patients show no evidence of recurrent disease. MRI of the breast is a useful technique for identifying primary sites of malignancy in patients presenting with ipsilateral lymph nodes positive for metastatic adenocarcinoma when the physical and mammographic examinations are negative. 相似文献
78.
79.
Objective To study the character of cervical lymph nodes metastasis in nasopharyngeal carcinoma(NPC) by contrast-enhanced uhrasonography(CEUS) and time-intensity curve. Methods Forty-one lymph nodes of metastasis from 32 patients were studied by CEUS. The enhancement of echogenicity was evaluated,and the time-intensity curve was analyzed. Results Of the 41 lymph nodes examined, 10 (24.4%) showed intense homogeneous enhancement by CEUS, 23 (56.1%) showed inhomogeneous enhancement and 8 (19.5 %) showed scarce intranodal enhancement. There were 20 (48.8%) lymph nodes showed necrosis. Most of the lymph nodes (92.7%) showed peripheral type blood flow, 3 (7.3) % showed mixed type blood flow. There were significant differences in them(P < 0.01). The time-intensity curve displayed steeply in upslope, and gently in decent. The arrival time(AT), time to peak(TTP), peak intensity (PI) ,area and gradient were (7.2±2.5)s,(7.6±2.3)s,(9.5±3.3)dB,(203.4±45.7)dB· s,1.2±0.5 respectively. Between the lymph nodes with envelope infringed and not, there were significant differences in PI and area, while there were not significant differences in AT, TTP and gradient. Conclusions The metastasis cervical lymph nodes of NPC had specific character by CEUS and time-intensity curve. In this way,it may help us to diagnosis cervical lymph nodes metastasis of NPC,and provide more information for the therapy and prognosis judgement. 相似文献
80.
Tatsuo Uchida Takahiko Tokumaru Hiroshi Kojima Katsura Nakagawaji Munehisa Imaizumi Toshio Abe 《Surgery today》1992,22(3):265-268
A 36 year old woman was admitted to our department because of a chest X-ray which showed multiple developing shadows. She underwent bilateral exploratory thoracotomies and a total 5 tumors were resected and pathologically diagnosed as benign metastasizing leiomyoma, the largest of which was positive for the progesterone receptor and negative for the estrogen receptor. A histogram of this tumor using a flow cytometer showed a diploid pattern and 4.6 percent of the S phase which was not more than that of a leiomyoma of the uterus from another patient. Two months later, she underwent a hysterectomy and bilateral salpingo-oophorectomy for treatment of the positive progesterone receptor in the pulmonary lesions. The resected uterine myoma and normal myometrium showed positive estrogen and progesterone receptors. For the subsequent 28 months she has been free of any further symptoms. Benign metastasizing leiomyoma of the uterus is a rare disease and very interesting because of its histological benignity and hormonal dependency. However, according to the literature, it is often confused in entity due to the fact that normal lung tissue also possesses hormone receptors. Considering our data on hormone receptors, it is rational to think that multiple leiomyomatous lesions in the lung should only be diagnosed as benign metastasizing leiomyomas when they possess positive estrogen and progesterone receptors. 相似文献