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41.
Fibronectins are a family of glycoproteins with modular functional domains. They mediate cell-cell and cell-matrix interactions which are important in embryogenesis, wound healing, metastasis and other processes. We present data on the influence of fibronectin on wound implantation of a murine mammary carcinoma line, TA3Ha. Fibronectin used in these studies was derived from bovine plasma, human serum, human foreskin fibroblasts, and mouse embryo cultures. TA3Ha cells rarely form tumors in the liver of syngeneic mice when injected intravenously but after hepatic wedge resection, 45% (107/240) of the mice develop tumors in the hepatic wound. Wound implantation is markedly reduced when the cells are pre-exposed to 200 µg/ml bovine plasma fibronectin (13%, P = 0.007), human serum fibronectin (0%, P = 0.02), human cellular fibronectin (0%, P = 0.02), or mouse cellular fibronectin (0%, P = 0.04). Lung colonization is also reduced by these fibronectins. These effects are not due to a cytotoxic action of fibronectin, since intraperitoneally injected fibronectin-treated cells form ascites tumor as effectively as do control untreated cells. Local application of a solution containing 0.25 mg/ml mouse cellular fibronectin to the hepatic wound reduces the frequency of tumor implantation from 45% to 5% (1/21, P = 0.001). No tumor implantation inhibition is seen when only suspending medium or albumin in suspending medium is used. The mechanism by which topical application of fibronectin reduces hepatic wound implantation of tumor cells is unclear, but this finding raises an exciting possibility of preventing local recurrence of cancer.  相似文献   
42.
乙/丙型肝炎病毒双重感染患者前C区终止变异低频率   总被引:1,自引:0,他引:1  
目的了解乙型肝炎病毒(HBV)与丙型肝炎病毒(HCV)双重感染患者前C区基因变异,及其可能的临床意义。方法用聚合酶链反应(PCR)与限制片段长度多态性(RFLP)来分析25例HBVDNA和HCVRNA均阳性(A组)和31例HBsAg和HBVDNA阳性但抗-HCV和HCVRNA均阴性(B组)的慢性肝病患者前C区密码28终止变异(终28)。结果HBV和HCV双重感染患者(A组)血清HBVDNA第1次PCR阳性率(16%)明显低于单独HBV感染组(65%)(P<0.001);前C终28检出率(28%)亦明显低于单独HBV感染(68%)(P<0.001)。结论提示双重感染患者HBV前C终止变异低频率可能与HBV低水平复制有关  相似文献   
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In 2 unrelated families 9 males presented with ataxia, apraxia, and neuropsychological abnormalities or mental deficiency, inherited as an X-linked recessive syndrome with partial clinical expression in obligate female carriers. The symptoms were present in early childhood and were non-progressive. Additional findings in 2 males were congenital "club-feet" and generalized seizures. The affected males were 13-62 years old at the time of our examination. Chromosome abnormalities including fragile X fra(X) could not be demonstrated in any case. Results of metabolic screenings were also normal. The clinical picture with X-linked recessive inheritance distinguishes this syndrome from previously described inherited hereditary ataxias.  相似文献   
46.
新型微波热疗机研制及其临床应用   总被引:6,自引:0,他引:6  
重点对新型电脑微波热疗机的构成、测温控温方案进行了研究。采用自适应广义预测控制算法对热疗温度进行控制,解决了因更换不同辐射器导致对象特性变化使控制性能降低的问题,从而得到了满意的疗效。文中介绍了该仪器关键的硬件、软件设计,基本的特点和临床应用  相似文献   
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Six cases of uncommon profunda femoris artery injury are analyzed. One half of the cases were not treated surgically at the time of injury and resulted in chronic arteriovenous fistulas. Even after operative correction, residual symptoms persisted in two of these three cases. The generous use of arteriography is recommended in cases of proximal thigh penetrating injuries to avoid this problem. Either repair or ligation of the injured vessel yielded the same good results. The postoperative hospital stay was short in all instances, ranging from four to eight days, and there were no deaths.  相似文献   
49.
采用多分辨率分析和人工神经网络相结合的方法实现对心室晚电位的检测。首先利用多分辨率分解技术提取高分辨率心电信号不同频带的能量构成一组特征值 ,再利用这些特征值训练BP神经网络 ,并完成对心室晚电位的识别。经过对 2 8例 3导高分辨率心电图实验数据的处理 ,取得了较高的识别准确率  相似文献   
50.
OBJECTIVE: To investigate the incidence of chromosome 11 abnormality in acute myeloid leukemia and its relationship with the clinical aspects and prognosis. METHODS:Conventional cytogenetic analysis of R-band was used to detect the abnormalities of chromosome 11 in 356 acute myeloid leukemia patients. RESULTS: Thirty-four out of 356 patients (9.55%) had abnormalities of chromosome 11, of which 20 (58.8%) involved in 11q23, 7 (19.9%) had translocations involving 11p15, 5 (14.7%) had-11, and the rest had other abnormalities such as +11, and t(11;14). The incidence of 11q23 involvement in M4 and M5 was higher than other subtypes of acute myeloid leukemia (AML). Ten cases with 11q23 abnormality had additional cytogenetic aberrations. In 30 cases treated with chemotherapy, 13 cases acquired complete remission (CR). The CR rate was lower than that of whole cases of acute myeloid leukemia(34.3% versus 64.0%). The CR rate of AML with 11q23 abnormality was lower than that of AML with normal karyotype (25% versus 55.6%). In other 10 patients with additional chromosome aberrations, the CR rate was lower than that of AML with 11q23 alone. In 7 patients with translocations at 11p15, only 3 patients acquired CR, and 2 patients relapsed early. Only 2 patients acquired CR in 5 patients with-11. CONCLUSION: 11q23 was a frequent aberration in chromosome 11 anomaly, which was often detected in M4 and M5. It might be associated with the pathogenesis of acute monolytic leukemia. The patients with chromosome 11 anomaly had poorer prognosis.  相似文献   
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