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61.
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   
62.
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   
63.
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   
64.
Early gastric cancer manifested as brain metastasis: Report of a case   总被引:1,自引:0,他引:1  
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   
65.
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   
66.
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   
67.
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   
68.
We report a patient with metastatic thyroid carcinoma invading the esophagus in whom barium and MR examinations revealed an expansile intraluminal mass indistinguishable from that of a primary esophageal malignancy. Metastatic thyroid carcinoma should therefore be included in the differential diagnosis of an expansile esophageal mass. As in our patient, MR imaging may be useful for showing that the mass originates in the thyroid gland.  相似文献   
69.
Recent advances in molecular lymphology and lymphatic phenotyping techniques in small animals offer new opportunities to delineate mutant mouse models. Chy-3 mutant mice were originally named for their chylous ascites, but the underlying lymphatic disorder was not defined. We now re-examined these mice and applied advanced genotyping and lymphatic phenotyping techniques to pinpoint the specific lymphatic defect in this mouse model. We demonstrated that Chy-3 mice carry a large chromosomal deletion that includes Vegfc and narrowed this region by monitoring the heterozygosity of genetic markers. We found that Chy-3 mice not only exhibited chylous ascites but also lymphedema of the hind paws and, in approximately half of the males, lymphedema of the penis. Visual lymphangiography and immunofluorescence staining showed a hypoplastic dermal lymphatic network, whereas the blood vasculature appeared unaffected. This hypoplastic lymphatic network was functional, and all adult Chy-3 mice exhibited a lateral lymphatic pathway directly connecting the inguinal to the axillary lymph node. The dermal superficial to deep lymphatic connections in upper limbs and in all cervical regions were intact and functionally drained the upper body. Lymphatic tracer was not transported from the dermal to the deep truncal lymphatic system in the lower limbs, even though the deep lymphatic vessels and nodes were present and patent. These findings further delineate the lymphatic phenotype of Chy-3 mice, identify a collateral lymph drainage pathway previously undescribed in other genetic models of lymphedema, and demonstrate a predilection for lymphatic abnormalities of the lower limbs.  相似文献   
70.
Summary The efficacy and safety of ivermectin in the treatment of filariasis due to Wuchereria bancrofti was assessed by a meta-analysis of the results from 15 published clinical trials. Seven hundred and forty-eight microfilaraemic patients were enrolled in 7 dose-finding and 8 comparative studies. Administered as a single dose, ivermectin induced nearly complete clearance of microfilariae from the blood from the first day to 30 days post-treatment, followed by gradual recurrence of microfilaraemia and increase in its intensity. Higher doses of ivermectin showed greater clearance effects and maintained lower microfilaraemia levels for a longer time. The adverse reactions caused by the drug were flu-like, transient, generally mild and well tolerated by patients. The frequency and intensity of adverse reactions were strongly associated with pretreatment microfilaria counts in the blood, but independent of dose. The findings of the meta-analysis suggest that ivermectin given at a single annual dose of 200 μg/kg body weight or higher, whether or not in combination with DEC, has great potential for therapeutic strategies to control bancroftian filariasis.  相似文献   
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