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11.
Oncogenesis is the consequence of a series of genetic alterations that allow unrestrained cellular growth, tissue invasion, and eventual metastases. Tumor-related genes can be classified into functional categories. Proto-oncogenes/oncogenes have a stimulatory role in cell growth, and the inactivation of cancer-suppressor genes/antioncogenes results in the loss of cell cycle regulation. More recently, three other groups of tumor-related genes have been recognized. They include the antiapoptosis genes which protect from programmed cell death, the antimetastasis genes, and multidrug resistance genes. Besides aiding in tumor diagnosis, the detection of such tumor-associated genes and their products allows the identification of individuals with an inherited predisposition to neoplastic growths, and the overexpression of many of these oncogene products has been shown to be a potential marker of tumor behavior and a predictor of treatment outcome and response. The ability to utilize DNA and RNA probes for nucleic acid hybridization and polymerase chain reaction procedures in cell and tissue preparations of solid tumors and lymphoid proliferations expands and complements the information provided by immunohistochemical techniques. These probes allow direct visualization and correlation of specific genes and their protein products with cytomorphologic features, and form a powerful addition to the armamentarium of the cytopathologist and surgical pathologist. © 1995 Wiley-Liss, Inc. 相似文献
12.
1,25-Dihydroxyvitamin D3 Induces Nitric Oxide Synthase and Suppresses Growth of Mycobacterium tuberculosis in a Human Macrophage-Like Cell Line 总被引:3,自引:0,他引:3 下载免费PDF全文
13.
脑啡肽与生长抑素在鸡视网膜无长突细胞共存的免疫组织化学研究 总被引:1,自引:0,他引:1
本文介绍用免疫组织化学的单标和双标技术研究脑啡肽(ENK)和生长抑素(SOM)在鸡视网膜无长突细胞的定位和共存。单标的实验结果表明,一些SOM免疫反应阳性无长突细胞的形态、胞体在内核层的位置及其突起在内网层的分支式样与某些ENK免疫反应阳性无长突细胞相似,虽然其突起在内网层的第3、4亚层形成的丛网不象ENK免疫反应阳性突起那样丛密,在内网层的第5亚层也未见SOM免疫阳性突起。双标的实验结果表明,一些无长突细胞显示ENK和SOM两种免疫阳性反应,而另一些无长突细胞分别只显示ENK或SOM阳性免疫反应。文中还对视网膜神经多肽间或与经典神经递质的共存进行了讨论。 相似文献
14.
Duchenne muscular dystrophy is a severe life-threatening X-linked recessive disorder, caused by mutations in the dystrophin gene, for which currently there is no effective treatment. Because of the large size of the dystrophin cDNA (14 kb) this precluded it from being used in early adenovirus- or retrovirus-based gene therapy vectors. However, some therapeutic success has been achieved in mdx mice using adenovirus- and retrovirus-mediated transfer of a 6.3 kb recombinant mini-dystrophin cDNA. Despite this, problems with immunogenicity and inefficient transduction of mature myofibres make these vectors less than ideal for gene transfer to skeletal muscle. Adeno-associated viral (AAV) vectors overcome many of the problems associated with other vector systems. However, AAV vectors can only accommodate <5 kb of foreign DNA. For this reason we have produced a micro-dystrophin cDNA gene construct that is <3.8 kb. This construct, driven by a CMV promoter, was introduced into the skeletal muscle of 12-day-old nude/mdx mice using an AAV vector, resulting in specific sarcolemmal expression of micro-dystrophin in >50% of myofibres up to 20 weeks of age, and effective restoration of the dystrophin-associated protein (DAP) complex components. Additionally, evaluation of central nucleation indicated a significant inhibition of degenerative dystrophic muscle pathology. We have therefore shown that the current micro-dystrophin gene delivered in vivo using an AAV vector is not only capable of restoring sarcolemmal DAP complexes, but can also ameliorate dystrophic pathology at the cellular level. 相似文献
15.
Ursula R. Kees Jette Ford Pamela R. Ranford Susanne E. Peroni Jaclyn A. Biegel Annette H. Parmiter Lavinia A. Hallam Michael L. N. Willoughby Dominic Spagnolo 《Genes, chromosomes & cancer》1994,9(2):129-135
We have established two cell lines, PER-452 and PER-453, from an 8-month-old girl with an extensive pineoblastoma. Characterization of these lines revealed that the proto-oncogenes MYC and MYCN were not amplified, but both cell lines showed MYCN expression comparable to a cell line with 200-fold MYCN amplification. Both cell lines contained an i( 17q). These results support the concept that pineoblastomas belong to a larger group of primitive neuroectodermal tumors of the central nervous system. These two cell lines provide a unique opportunity to investigate the molecular genetic mechanisms underlying these neoplasms further. Genes Chrom Cancer 9:129-135 (1994).© 1994 Wiley-Liss, Inc. 相似文献
16.
17.
Richard S. Surwit Marilyn N. Bradner Cynthia H. Fenton Robert N. Pilon 《Psychophysiology》1978,15(4):320-323
The purpose of the present study was to assess the relationship between lateralization of body image and right versus left vasomotor activity. Fifteen right-handed female patients suffering from idiopathic Raynaud's disease demonstrated a relationship between the extent of right lateralization of body image and bilateral digital skin temperature during a controlled temperature stress test. In addition, subjects showing a reliable right side awareness demonstrated more unilateral vasospastic attacks in their right hand than their left hand white subjects showing no clear right lateralization by body image reported more left hand attacks than right hand attacks. These results were taken as consistent with previous work on the relationship between skin conductance and lateralization of body image. 相似文献
18.
Rodi?O.?Ojoo George?E.?Otiang’a-Owiti Dominic?Oduor-Okelo Daniel?W.?Onyango Email author 《Brain structure & function》2005,209(5):381-389
Spermatogenesis in the thick-tailed bush baby, Otolemur garnetti, was studied using light microscopy. The stages and stage frequencies of the cycle of the seminiferous epithelium were determined using semithin sections stained with methylene blue-azure II. These sections were obtained from the testes of six healthy adult males (n=6). They revealed 11 stages of the seminiferous epithelial cycle in this species. The mean relative frequencies of the stages I–XI were 10.9, 6.0, 5.9, 7.3, 13.2, 10.7, 11.7, 9.2, 7.6, 8.9 and 8.6, respectively. Comparisons were made between the frequency data in the thick-tailed bush baby and equivalent data in the rat, hamster, macaque, baboon, chimpanzee and man. There was a significant correlation (P<0.05) between the Otolemur data and equivalent stage frequency data of two rodent species (rat and hamster) and monkey (Macaca arctoides). However, there was no significant correlation between the present data and those of the baboon, chimpanzee and man. Possible phylogenetic implications of these findings are discussed. 相似文献
19.
TNF-alpha impairs peripheral tolerance towards beta-cells,and local costimulation by B7.1 enhances the effector function of diabetogenic T cells 总被引:1,自引:0,他引:1
Skak K Guerder S Picarella DE Brenden N Flavell RA Michelsen BK 《European journal of immunology》2003,33(5):1341-1350
Maintenance of peripheral tolerance and inactivation of autoreactive T cells is based on a delicate balance between pro-inflammatory and protective cytokines that is poorly understood. We have here addressed how the local expression of the inflammatory cytokine TNF-alpha can impair peripheral tolerance and lead to autoreactivity. After transplantation of pancreata that are immunogenic due to beta-cell expression of B7.1 and TNF-alpha, into thymectomized and euthymic syngeneic mice, we found that only euthymic mice rejected the grafts. This result suggests that under normal circumstances autoreactive T cells are functionally inactivated, and initiation of an autoreactive response requires de-novo generation of T cells. By contrast, thymectomized mice expressing TNF-alpha on the endogenous islets rejected the grafts, showing that expression of TNF-alpha prevents functional silencing of the autoreactive T cells. Thus, this study provides a mechanism by which TNF-alpha and possibly chronic inflammatory responses may promote autoimmune diseases. Furthermore, we have investigated whether B7.1 can enhance T cell responses of already activated T cells leading to islet rejection. By transplantation of wild-type and B7.1-expressing islets into overtly diabetic mice we found that only the wild-type islets could restore normoglycemia, suggesting that costimulation by B7.1 is required in the expansion or effector phase of the response. 相似文献
20.
Elizabeth Billington Jane Simpson Jen Unwin Dominic Bray David Giles 《British journal of health psychology》2008,13(4):683-699
Objectives Hope is important in determining positive outcomes in a range of chronic illnesses. This study examined the role of hope in adjustment to end‐stage renal failure (ESRF) and consequent dialysis. Design A cross‐sectional design examined the ability of hope to predict adjustment to ESRF over and above other relevant variables. Methods Individuals receiving dialysis at 4 units in the North‐West UK were invited to take part in the study. 103 questionnaire packs were included in the analysis. Multiple regression equations determined whether hope was able to predict significant variance in adjustment over and above that accounted for by other factors (demographic and illness‐related factors, perceived control, and social support). Measures of anxiety, depression, and quality of life constituted a multidimensional measure of adjustment to ESRF. Results Each of the regression models was significant. Hope emerged as an independent significant predictor in five of the multiple regressions: anxiety; depression; effects and symptoms of kidney disease; and mental health quality of life. Age also emerged as an important predictor of outcome. Conclusions It appears that hope is a significant predictor of adjustment to ESRF. Clinical implications of this research are discussed, along with suggestions for future research. 相似文献