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排序方式: 共有1569条查询结果,搜索用时 15 毫秒
1.
Yawata Ayumi; Kanzaki Akio; Gilsanz Florinda; Delaunay Jean; Yawata Yoshihito 《Blood》1997,90(6):2471-2481
2.
Yamamoto Kazuhiko; Nakajima Akira; Eimoto Hiroyuki; Tsutsumi Masahiro; Maruyama Hiroshi; Denda Ayumi; Nii Hiroaki; Mori Yukio; Konishi Yoichi 《Carcinogenesis》1989,10(9):1607-1611
The carcinogenic activity of endogenously synthesized N-nitrosobis(2-hydroxypropyl)amine(BHP) was investigated in male Wistar rats administered bis(2-hydroxypropyl)amine(BHPA) mixed in powder diet at a concentration of 1%, and sodiumnitrite (SN) dissolved in distilled water at concentrationsof 0.15 and 0.3%, for 94 weeks. Urinary excretion of BHP wasdetected in rats given 1% BHPA and 0.3% SN but not in the groupsreceiving either of these precursors alone. Nasal cavity, lung,esophagus, liver and urinary bladder tumors were found in animalstreated with combinations of 1% BHPA and 0.15 or 0.3% SN, suggestingthat the target organs of the endogenously synthesized BHP aresimilar to those affected when the carcinogen is administeredexogenously. The incidences of nasal cavity and lung tumorsreached 74 and 58% in rats given 1% BHPA and 0.3% SN, respectively.Tumors at sites other than target organs were only found atlevels similar to those previously reported for spontaneoustumors in male Wistars. The present results clearly indicatedthe tumor inducibility of a nhrosatable amine, BHA, throughan endogenous nitrosation by feeding to rats in conjunctionwith nitrite, and provide further suggestive evidence that endogenousnitrosations of environmental nitrosatable amines can be a potentialrisk factor in human cancer development. 相似文献
3.
Introduction The authors report a case of interhemispheric ependymal cyst accompanied with agenesis of the corpus callosum in a fetus.
Discussion Routine ultrasound and subsequent magnetic resonance imaging of a 20-year-old woman at 33 weeks and 1 day of gestation detected
a large interhemispheric cystic lesion in the fetal cranial cavity. Caesarian section was carried out at 36 weeks because
of the progressive enlargement of the fetal head. The cyst was multiloculated and a cyst peritoneal shunt placement resulted
in collapse of the drained cyst components followed by enlargement of others. After wrack-a-mole-like shunt revisions, open
surgery was performed at the age of 2 years. Cyst walls were fenestrated and the cavities were communicated with each other
and eventually with the lateral ventricle. Pathological diagnosis of the cyst wall was ependymal cyst. The boy is now 3 years
old, and growing without apparent developmental delay or recurrence. Current concept and management policy of the interhemispheric
cyst accompanied with agenesis of the corpus callosum is reviewed. 相似文献
4.
Possible involvement of arachidonic acid metabolism in phenobarbital promotion of hepatocarcinogenesis 总被引:8,自引:4,他引:4
Denda Ayumi; Ura Hitoshi; Tsujiuchi Toshifumi; Masahiro Tsutsumi; Eimoto Hiroyuki; Takashima Yoshiharu; Kitazawa Shunji; Kinugasa Tetsuo; Konishi Yoich 《Carcinogenesis》1989,10(10):1929-1935
The effects of inhibitors of arachidonic acid metabolism andantioxidants on the rat liver tumor promotion activity of phenobarbital(PB) were assessed using the enzyme-altered focus as the end-pointlesion. Fischer 344 male rats were initiated with N-nitrosodiethylamine(200 mg/kg) and then divided into five groups placed on basaldiet, diet containing 0.05% PB, diet containing 0.05% PB plus0.75%, 1% or 1.5% levels of various inhibitors of arachidonicacid metabolism or antioxidants, or diet containing 1% or 1.5%inhibitors or antioxidants alone for 10 weeks, and then killed.-Bromo phenacyl bromide, an inhibitor of phospholipase A2 significantly inhibited the promotion activity of PB at dose levelsof 0.75% and 1.5%, reaching plateau at 0.75%. Both quercetin,an inhibitor of lipoxygenase, and morin, a dual inhibitor oflipoxygenase-cyclooxygenase, significantly reduced the promotionactivity of PB at the 1.5% but not 0.75% dose levels. Moreover,acetylsalicylic acid, an inhibitor of cyclooxygenase dose-dependentlyinhibited the promotion activity of PB. Among the antioxidantsinvestigated, vitamin E did not affect, but n-propyl gallateand ethoxyquin exerted a dose-dependent inhibition of PB promotion.These results are strongly suggestive of an involvement of phospholipaseA2 lipoxygenase and cyclooxygenase arachidonic acid metabolicpathways in the mechanisms underlying PB enhancement of hepatocarcinogenesis. 相似文献
5.
Fukui K Kominami R Kaneuji A Matsumoto T Shinohara H 《Okajimas folia anatomica Japonica》2004,81(4):57-62
We report a new method of perfusion fixation for the proximal one-third of the femur of the Japanese white rabbit. Fluids to flush the blood and fix the marrow were injected into the abdominal aorta and drained from the stump of the femur. The oozing of the fluids from the stumps guaranteed complete flushing and fixation. The new method facilitated fixation and decreased the volume of necessary fluids. Scanning electron microscopy (SEM) images of bone marrow fixed using the new method and using the conventional method did not differ. Large fat globules were not observed in the SEM specimens produced using either the new or the conventional method. 相似文献
6.
Tanaka G Kanaji S Hirano A Arima K Shinagawa A Goda C Yasunaga S Ikizawa K Yanagihara Y Kubo M Kuriyama-Fujii Y Sugita Y Inokuchi A Izuhara K 《International immunology》2005,17(6):797-805
It is widely known that IL-4 and IL-13 act on various kinds of cells, including B cells, resulting in enhancement of proliferation, class switching to IgE and expression of several surface proteins. These functions are important for the recognition of the various antigens in B cells and are known to be involved in the pathogenesis of allergic diseases. However, it has not been known whether IL-4/IL-13 is involved in the metabolism of various kinds of xenobiotics including 2,3,7,8-tetra-chlorodibenzo-p-dioxin (TCDD), and it remains undetermined whether TCDD, an environmental pollutant, influences IgE production in B cells, exaggerating allergic reactions. We identified IL-4- or IL-13-inducible genes in a human Burkitt lymphoma cell line, DND-39, using microarray technology, in which the AHR gene was included. The AHR gene product, the aryl hydrocarbon receptor (AhR), was induced by IL-4 in both mouse and human B cells in a STAT6-dependent manner. IL-4 alone had the ability to translocate the induced AhR to the nuclei. TCDD, a ligand for AhR, rapidly degraded the induced AhR by the proteasomal pathway, although IL-4-activated AhR sustained its expression. AhR activated by IL-4 caused expression of a xenobiotic-metabolizing gene, CYP1A1, and TCDD synergistically acted on the induction of this gene by IL-4. However, the induction of AhR had no effect on IgE synthesis or CD23 expression. These results indicate that the metabolism of xenobiotics would be a novel biological function of IL-4 and IL-13 in B cells, whereas TCDD is not involved in IgE synthesis in B cells. 相似文献
7.
Yoko Mamada Takahiro Murata Ayumi Taniguchi Yuki Hasegawa Tetsuomi Suzuki Kyoko Kohda Kiyoto Nasuno Toshiaki Watanabe Seiji Yamaguchi Akira Ishiguro 《Arerugī》2008,57(5):552-557
We reported a 4-month-old girl with biotin deficiency caused by amino acid formula. Two weeks after birth, she was diagnosed as having a milk protein allergy. After switching to amino acid formula from usual formula, her symptoms and laboratory findings became normal. About three weeks after the beginning of amino acid formula, she developed intractable skin erosions around the eyes, mouth, neck, and anogenital area. By measuring concentrations of some trace elements, she was diagnosed as having a biotin deficit, because of the organic aciduria and undetectable serum biotin concentration. Her serum biotinidase level was normal. Upon administration of oral biotin supplementation, all her symptoms and laboratory findings were dramatically improved. Since amino acid formula contains very few biotin, we should pay attention to biotin deficiency when infants receiving amino acid formula. 相似文献
8.
Yamada A 《Shinrigaku kenkyu : The Japanese journal of psychology》2004,75(2):134-141
This study investigated the effects of repeated exposures to male and female targets on trait impressions and the role of stereotyped knowledge for the target's social category in impression formation process. The participants were repeatedly exposed to slides of male and female faces for subliminal durations. For each of 12 pairs containing both previously presented slide and newly presented slide, the participants made forced-choice liking judgments (Experiment 1), trait judgments (Experiment 2) and recognition judgments (Experiments 1 and 2). It was found that participants' attitude toward the targets became more positive, even though target recognition was not significantly greater than the chance level. Yet, when the dimension of judgment was stereotypically associated with the target's social category, exposure effects were obtained for the targets whose social category and its dimension were inferentially matched, but not obtained for the targets whose social category and its dimension were not inferentially matched. Some theoretical implications of the role of social category information in the mere exposure phenomenon are discussed. 相似文献
9.
Sasaki F Doshita A Matsumoto Y Kuwahara S Tsukamoto Y Ogawa K 《Cells, tissues, organs》2003,173(2):65-74
Pituitary glands of chicken, from stages 20 (70 approximately 72 h of incubation) to 46 (20 days) of Hamburger and Hamilton (1951), were studied by immunocytochemical and histological stainings and India ink injection into blood vessels. Using the distribution pattern of 6 types of immunoreactive adenohypophyseal cells and the location of pituitary stalk as guideposts, we found how specific areas in the epithelium of Rathke's pouch differentiate into specific regions of the adenohypophysis at 20 days. In the sagittal plane, the walls of Rathke's pouch were tentatively divided into the upper part (A(1) + A(2)) and lower part (A(3)) of the anterior wall, and the posterior wall (P(1) + P(2) + P(3)). The cephalic lobe was mainly assembled by the proliferation of parenchymal cells in the areas A(2) + A(3) + P(2) of Rathke's pouch epithelia at 3 days of incubation. The caudal lobe was derived from A(1) + P(1) + P(3). The pars tuberalis was derived from A(1) + A(2). Thus, the avian adenohypophysis is established at 13 days, though the blood supply to the pars distalis is established at 20 days. Therefore, the cephalic lobe and caudal lobe of the pars distalis and the pars tuberalis of the chicken adenohypophysis are derived from specific areas of the cell cords of Rathke's pouch at 3 days of incubation. 相似文献
10.
Ura Hitoshi; Denda Ayumi; Yokose Yoshihiko; Tsutsumi Masahiro; Konishi Yoichi 《Carcinogenesis》1987,8(11):1595-1600
The effects of dietary vitamin E (VE) on the steps of hepatocarcinogenesis,the induction and growth of -glutamyltranspeptidase (GGT)-positivefoci and their evolution into persistent nodules, were analyzedin the liver of rats treated with diethylnitrosamine (DEN).The induction of GGT-positive foci was inhibited by a diet containing0.361.5% VE given after initiation with 200 mg/kg bodyweight (b.w.) DEN for 6 weeks with partial hepatectomy (PH)on week 3. The numbers and areas of GGT-positive foci were enhancedby diets containing 036 and 0.72% VE, given for 1 week afterinitiation with 10 mg/kg b.w. DEN and PH, followed by selectionby 0.02/ 2-acetylaminofluorene (AAF) and carbon tetrachloride(CCl4), but these were not enhanced by a diet containing 1.5%VE. Remodeling of hyperplastic nodules was not affected by thediet containing 0.72% VE given after initiation with DEN andselection for 12 weeks. The staining characteristics of GGTwere different between remodeling and persistent nodules, exceptfor those of the glutathione-S-transferase placental form (GST-P).The results obtained suggest that VE could prevent the veryearly events during hepatocarcinogenesis, the induction of phenotypicallyaltered foci, but could no longer affect the later stages, theevolution of foci into persistent nodules. 相似文献