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GS Wood 《Canadian Metallurgical Quarterly》1998,29(1-2):93-101
To observe the expression of p16, pRb, cdk4 and cyclinD1 in non-small cell lung cancers, 104 cases of resected lung cancers were collected, which included squamous cell carcinomas, adenocarcinomas and large cell carcinomas. Immunohistochemistry assay was carried out. The results showed that 67% of squamous cell carcinomas and 46% of adenocarcinomas expressed p16, 64% of squamous cell carcinomas and 85% of adenocarcinomas expressed pRb and 66% of cancers expressed p16 or pRb. About 70% of the tumors expressed cyclinD1. More than 90% of the tumors expressed cdk4 and there was an increased trend with decreasing differentiation of both squamous cell carcinomas and adenocarcinomas. Sixty-seven percent of the highly differentiated and 100% of the poorly differentiated squamous cell carcinomas expressed cdk4. The aberrant p16 and pRb gene product expression played a significant role in the development and histological subtype of lung cancers by conditioning the biological behavior of NSCLC. cdk4 was an important factor in histological differentiation. 相似文献
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Ninety-two patients with Dukes' class C colonic carcinoma, divided equally into those who survived 5 years or more and those surviving less than 5 years after resection for cure, underwent evaluation of multiple histopathologic characteristics of the primary tumor and the uninvolved regional lymph nodes. These characteristics were analyzed by the chi-square test for correlation with survival. A statistically significant correlation (P less than 0.05) in the group who survived 5 years or more was observed for Broders' grades 1 and 2, tumor not involving serosa, and a pushing tumor margin. Of the 14 patients who had a pushing tumor margin and tumor not involving serosa, 12 (86%) survived 5 years or more. Seven patients had an infiltrating tumor margin and peritumor venous invasion, and of this group, only one (14%) survived 5 years or more. Histopathologic characteristics of host immune reaction at the tumor or in the uninvolved regional lymph nodes did not correlate with survival. 相似文献
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If a spinal root of a baboon or rhesus monkey is trapped in an initially loose-fitting silicone rubber channel containing two or more platinum electrodes, electrical pulses sent through these electrodes can stimulate nerve fibres close to the cathode and block the resulting impulses close to the anode. We show (1) how anodal break excitation and excitation of fibres outside the silicone rubber channel can be avoided; (2) that an implant 26 months old behaves like a recent one; (3) that in a root containing somatic motor fibres and parasympathetic fibres, all somatic motor fibres can be blocked and most or all parasympathetic fibres excited but not blocked; (4) that provided that the electrodes pass no net direct current, prolonged stimulation with block can be harmless; (5) how block can be achieved in one direction only along a root; (6) that a peripheral nerve can be blocked by the same techniques. 相似文献
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T Cartmell T Southgate GS Rees MG Castro PR Lowenstein GN Luheshi 《Canadian Metallurgical Quarterly》1999,19(4):1517-1523
Adenovirus-mediated gene transfer into the brain is associated with significant inflammation and activation of anti-vector and anti-transgene immune responses that curtail the gene delivery of adenoviruses and therapeutic efficacy. Elucidating the molecular mediators of inflammatory and immune responses to adenoviruses injected into the brain should allow us to inhibit their inflammatory actions, thereby reducing vector clearance and enhance adenoviral-mediated gene transfer into the CNS. Cytokines are primary mediators of the immune response and are released during inflammation. Here we report for the first time that injection of replication-deficient adenovirus vectors into the cerebral ventricles of rats causes a rapid increase in body temperature. This fever response precedes any vector-encoded transgene expression and occurs with vectors encoding no transgene, as well as with vectors encoding a therapeutic transgene i.e., HSV1-thymidine kinase. No fever is detected after infection of the striatum, an important brain target in studies on neurodegeneration. After infection of the brain ventricles, CSF levels of immunoreactive tumor necrosis factor (TNF)-alpha and interleukin (IL)-1beta increase significantly (up to 300-fold). In the hypothalamus, the locus of thermoregulation in the brain, only IL-1beta and IL-6 are significantly elevated. A neutralizing TNF-alpha antibody has no effect on adenovirus-induced fever. However, pretreatment with either the IL-1 receptor antagonist or the cyclooxygenase inhibitor flurbiprofen completely abolishes adenovirus-induced fever, suggesting that IL-1 and prostaglandins are direct mediators of this response. These results are the first to demonstrate that IL-1, but not TNF-alpha, is the main mediator of a very early inflammatory response to adenovirus in the brain. 相似文献
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Wegener's granulomatosis (WG) is a systemic disease characterized by necrotizing granulomatous vasculitis that involves primarily the upper and lower respiratory tracts and, in most cases, the kidneys. Kidney involvement in WG presenting as a mass is recognized, but is very rare. We describe a case of WG presenting with upper and lower respiratory symptoms and a renal mass due to both WG and renal cell carcinoma. 相似文献