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101.
Hiroyoshi Suzuki Miburu Emi Akira Komiya Yoshiyuki Fujiwara Ryuichi Yatani Yusuke Nakamura Jun Shimazaki 《Genes, chromosomes & cancer》1995,13(3):168-174
Human prostate cancers frequently show loss of heterozygosity at loci on the short arm of chromosome 8. In order to take a step toward isolation of the putative tumor suppressor gene(s) on 8p via positional cloning, we performed high-resolution deletion mapping in 46 prostate cancers (stage B, 20 cases; stage C, 8 cases; endocrine therapy-resistant cancer death, 18 cases) using new 12 restriction fragment length polymorphism markers for this chromosomal region. Allelic losses were observed in 25 of the 44 cases (57%) that were informative with at least one locus. Detailed deletion mapping defined a 1.2 Mb commonly deleted region at 8p22-p2 1.3 flanked by markers cMSR-32 and C18- 105 1. A second region of common deletion was identified between C18-1312 and C18-494 at 8p21-8p11.22, suggesting that at least two tumor suppressor genes associated with prostate cancer are present on chromosome arm 8p. Allelic losses on 8p were observed more frequently in the cancer death cases (14/17, 82%) than in early-stage tumors (11/27, 40%; P < 0.01, Fisher's exact test). In two out of 7 patients for whom DNA was available from metastatic cancers as well as from normal tissues and primary tumors, the primary cancer foci had no detectable abnormality of 8p, but the metastatic tumors showed loss of heterozygosity. These results suggest that inactivation of tumor suppressor genes on 8p plays an important role in the progression of prostate cancer. © 1995 Wiley-Liss, Inc. 相似文献
102.
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104.
Phencyclidine increases extracellular dopamine metabolites in rat medial frontal cortex as measured by in vivo dialysis 总被引:1,自引:0,他引:1
An acute intraperitoneal injection of phencyclidine (PCP) caused a tetrodotoxin-reversible increase in extracellular release of 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) in the dialysates from the medial frontal cortex of the rat. Moreover, there was an increase in the tissue content of DOPAC and HVA with acceleration of dopamine (DA), but not noradrenaline, utilization in the cortical area after systemic administration of PCP. These results suggest that PCP facilitates DA metabolism in the medial frontal cortex by increasing impulse flow in the DA neurons projecting to the prefrontal region. 相似文献
105.
Toshio Nishikawa Takeshi Kasajima Akira Kajita Mitsunori Yamakawa Gengo Mabuchi Hideo Orihata Toshimitsu Shibata Makoto Nakazawa 《Pathology international》1988,38(5):683-691
A case of adrenocortical carcinoma associated with congenital heart defect in a 6-month-old Japanese girl is reported. A fist-sized tumor was incidentally noted in the right hypochondrium upon admission for cardiac surgery. No clinical endocrinopathy was evident in this case. The resected tumor was encapsulated with smooth surface and no invasion to adjacent tissues or organs was observed. Histologically, the tumor was composed of small cells with granular or clear cytoplasm, and occasional giant cells with single or multiple nuclei. By electron microscopy, the tumor cells showed various nuclear contours with distinct nucleoli and had a moderate amount of cytoplasm containing abundant rough endoplasmic reticulum and mitochondria with variable-sized electron-dense granules. Intercellular desmosome-llke junctions were observed in some tumor cells. Immunohistochemlcally, the tumor cells contained granules positive for estriol, progesterone and Cortisol. These morphological findings including electron microscopic features suggested that the tumor cells had a malignant character. 相似文献
106.
Koichi Kondo Yoshiyuki Miwa Kiichi Takemoto 《Macromolecular chemistry and physics.》1983,184(6):1171-1178
Active β-alanine esters having dipeptide groups, which are capable of forming hydrogen bonds between the side chains, were prepared in the form of hydrogen chloride salts. The polycondensation of these salts was studied in non-polar solvents, in the presence of triethylamine. In the case of the ester with β-alanyl-β-alanine as dipeptide moiety, the polycondensation proceeded smoothly in chloroform solution. To explain the characteristic feature of the polycondensation, an ordered aggregation of the ester molecules is assumed to play an important role. The ester with glycylglycine as dipeptide moiety, however, did not undergo a polycondensation. 相似文献
107.
Kobayashi M Masuda Y Fujimoto Y Matsuya T Yamamura K Yamada Y Maeda N Morimoto T 《Physiology & behavior》2002,75(3):377-385
Although rhythmic jaw movement in feeding has been studied in mammals, such as rats, rabbits and monkeys, the cellular and molecular mechanisms underlying it are not well understood. Transgenic and gene-targeting technologies enable direct control of the genetic makeup of the mouse, and have led to the development of a new category of reagents that have the potential to elucidate the cellular and molecular mechanisms of neural networks. The present study attempts to characterize rhythmic jaw movements in the mouse and to demonstrate its relevance to rhythmic jaw movements found in higher mammals using newly developed jaw-tracking systems and electromyograms of the masticatory muscles. The masticatory sequence of the mouse during feeding was classified into two stages, incision and chewing. Small and rapid (8 Hz) open-close jaw movements were observed during incision, while large and slow (5 Hz) open-close jaw movements were observed during chewing. Integrated electromyograms of the masseteric and digastric muscles were larger during chewing than those observed during incision. Licking behavior was associated with regular (8 Hz), small open-close jaw movements with smaller masseteric activity than those observed during mastication. Grooming showed variable patterns of jaw movement and electromyograms depending on the grooming site. These results suggest that there are neuronal mechanisms producing different frequencies of rhythmic jaw movements in the mouse, and we conclude that the mouse is useful for understanding rhythmic jaw movements in higher mammals. 相似文献
108.
Hirata T Iida A Shiraki-Iida T Kitazato K Kato A Nagai Y Hasegawa M 《Journal of virological methods》2002,104(2):125-133
An improved system is described to recover non-transmissible Sendai virus that lack the envelope fusion (F) gene from cloned cDNA. The system (1) used plasmids that expressed the F and the HN viral envelope proteins, as well as the plasmids that expressed the viral NP, P, and L proteins as helper plasmids for recovery, and (2) overlaid packaging cells that expressed the F protein. With this improved system, we have succeeded in recovery of F-defective Sendai virus expressing two foreign proteins, and expression vectors that do not contain the EGFP reporter gene. This system may provide the basis for constructing recombinant F-defective Sendai virus for preventing and treating human diseases in the form of vaccines and vectors for gene therapy. 相似文献
109.
110.
Hiroshi Fujiwara Atsushi Morita Hideyuki Kobayashi Katsura Hamano Yoshiyuki Fujiwara Koichi Hirai Masahiko Yano Tetsuji Naka Yukihiko Saeki 《Annals of allergy, asthma & immunology》2002,89(4):429-432
BACKGROUND: Idiopathic eosinophilic esophagitis (IEE) is a very rare disease characterized by thickening and eosinophil infiltration of the esophagus. The most potent chemotactic factor for eosinophils is eotaxin, and its pathophysiologic significance in IEE needs to be elucidated. OBJECTIVE: To study the association between eotaxin and IEE. METHODS: We examined eotaxin expression in the esophagus of an IEE patient in comparison to controls by immunohistochemistry using a monoclonal antibody for human eotaxin. We also measured the free eotaxin level and the total (free and bound-form) eotaxin level in blood by enzyme-linked immunosorbent assay before and after the initiation of steroid therapy. RESULTS: Most of the infiltrating eosinophils in the affected esophageal tissue showed immunohistochemical staining with anti-eotaxin antibody. In blood samples, the free eotaxin level was slightly elevated before treatment, whereas the total eotaxin level was within the normal range. Unexpectedly, the total eotaxin level increased dramatically after the initiation of steroid therapy, whereas the increase of free eotaxin was modest. CONCLUSION: Infiltrating eosinophils that express eotaxin and the changes of blood eotaxin levels during steroid therapy suggest that eotaxin may be associated with IEE. 相似文献