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51.
Tatsuo Michiue Akimasa Fukui Akira Yukita Kenji Sakurai Hiroki Danno Akira Kikuchi Makoto Asashima 《Developmental dynamics》2004,230(1):79-90
Wnt signaling pathways are involved during various stages in the development of many species. In Xenopus, the accumulation of beta-catenin on the dorsal side of embryo is required for induction of the organizer, while the head structure formation requires inhibition of Wnt signaling. Here, we report a role for xIdax, a negative regulator of Wnt signaling. XIdax is expressed in neural tissues at the neurula stage, and in the restricted region of the tadpole brain. Ectopic expression of xIdax inhibits the target gene expression, suggesting that xIdax can inhibit canonical Wnt signaling. To examine the function of xIdax, a morpholino oligo for xIdax (xIdaxMO) was designed. An injection into an animal pole cell caused a loss of forebrain. The anterior neural marker expression is decreased in xIdaxMO-injected embryo, suggesting that xIdax is required for anterior neural development. Moreover, a negative regulator that acts downstream of xIdax rescued this defect. We propose that Idax functions are dependent on the canonical Wnt pathway and are crucial for the anterior neural development. 相似文献
52.
A Yoshioka H Naka T Nishimura K Kuze I Tanaka S Mikami M Matsumoto K Yoshioka H Fukui 《The Japanese journal of human genetics》1989,34(2):135-141
Accurate first-trimester prenatal diagnosis was achieved in a Japanese haemophilia A family by the use of a restriction fragment length polymorphism (RFLP) located within the F.VIII gene. Since the pregnant woman's heterozygosity for BclI polymorphism in F.VIII/intron 18 (F8A) probe was informative, chorionic villus sampling (CVS) was performed at 9 weeks of gestation. Restriction analysis showed that the fetus was heterozygous for the BclI site and had received a normal paternal X chromosome (0.9 kb) and a normal maternal X (1.2 kb). Therefore, we concluded that the fetus was a non-carrier female. Pregnancy went to term and woman gave birth to an apparently healthy female. At one week after birth a coagulation study confirmed that the newborn infant is not a carrier. The first-trimester prenatal diagnosis of haemophilia A is possible by CVS due to a RFLP in the F.VIII gene. 相似文献
53.
54.
Takaaki Ohmori Ryo Tabei Keiji Fukui Kazuhiko Sadamoto Saburo Sakaki 《Pathology international》1989,39(3):190-194
Two cases of meningioma revealing conspicuous plasmo lymphocytic tissue and hyalinized fibrous tissue components are reported. Histopathological examination of the plasmo lymphocytic infiltration was performed. Both lesions showed polyclonality of plasma cells as revealed by positive reactions for 1gG and paraimmunoglobulin χ- and λ light chains, and amyloid infiltration into the fibrous stroma and blood vessel walls. The histochemical and immunohistochemical characteristics of the lesion in relation to its etiology are briefly discussed. Acta Pathol. Jpn. 32: 190∼194, 1989. 相似文献
55.
The manner of packing of the terminal DNA loci into nucleosomes and higher order structures may strongly influence their functional
interactions. Besides the structural flexibility of telomeric DNA sequences, conserved features of their chromatin including
short nucleosome phasing (157 bp) and nucleosome sliding have been described previously. To gain a complementary knowledge
of subtelomeres, we have analysed the chromatin structure of two subtelomeric tandem repeats from the plant Silene latifolia: X43.1 and 15Ssp. X43.1 shows two distinct nucleosome periodicities – 157 and 188 bp. Preferred positions of its two nucleosomes
have been mapped at both low and high resolution and the experimental results correspond to computer-predicted positions.
15Ssp is a newly-discovered sequence showing a telomere-associated position by PCR and a subtelomeric location by pulsed-field
gel electrophoresis and fluorescence in situ hybridisation. Its 159 bp sequence unit shows a tandem arrangement and the presence of micrococcal nuclease-hypersensitive
sites when either naked DNA or chromatin is digested. Use of a chemical nuclease results in a regular nucleosome ladder of
157 bp periodicity. Moreover, 15Ssp mononucleosomes show instability and absence of specific positioning, features typical
for telomeric chromatin.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
56.
Mitsuo Masuno Jun-Ichi Asano Kanji Yasuda Tomio Kondo Tadao Orii 《American journal of medical genetics. Part A》1993,45(1):65-67
We report on a 19-month-old girl with a derivative chromosome 9 and a recombinant chromosome 12 resulting from a maternal balanced complex rearrangement involving chromosomes 8, 9, and 12. The karyotype of the phenotypically normal mother was 46,XX,t(8;12) (9;12) (8qter→8p23::12q12→12q15::9q32→9qter;9pter→9q32::12q15→12qter;12pter→12q12::8p23→8pter). The child's karyotype was 46,XX,?9,?12, +der(9) (9pter→9q32::12q15→12qter),+rec(12) (12pter→12q15::9q32→9qter) mat. The child had severe growth retardation, minor anomalies including trigonocephaly, hypertelorism, broad nasal root, apparently low-set and posteriorly angulated ears, triangular face, pectus carinatum, clinodactyly of fifth fingers, and almost normal psychomotor development. To the best of our knowledge, there have been only 3 previous reports of recombination derived from parental complex chromosome rearrangements. In the recombination products, the chromosomes were apparently balanced and the offspring had no clinical abnormalities. The present case exhibited abnormalities and may have a submicroscopic aberration of 12q arising from crossing over during maternal meiotic pairing, although her chromosomes appeared to be balanced. © 1993 Wiley-Liss, Inc. 相似文献
57.
Makoto Yoshimura Isamu Sakurai Toshihiko Shimoda Kenji Abe Tadao Okano Toshio Shikata 《Pathology international》1981,31(4):711-717
Hepatitis B surface antigen (HBsAg) has been reported to be present in other organs than the liver.3,9 So far as our knowledge is concerned, however, any report of cases dealing with pancreatic diseases induced by hepatitis B virus (HBV) has not been described in the English and Japanese literature. We report an autopsy case with a pancreatic lesion characterized by damage of both exocrine and endocrine epithelial cells with inflammatory response, which were immunohistochemically found to be positive for HBsAg, and electron-microscopically to possess core-like particles In the nucleus and cytoplasm. 相似文献
58.
Kazuo Sugiyama Hideo Hatanaka Tadao Nakaya Minoru Imoto 《Macromolecular chemistry and physics.》1973,165(1):163-171
A study was made of the polymerization of acrylonitrile in dimethylformamide (DMF) initiated by the binary systems of tetramethyltetrazene (TMT) and p-substituted benzyl chlorides. The polymerization rate increased linearly with the σ-constants of substituents as electron-releasing groups were introduced to the phenyl ring of benzyl chloride. In order to elucidate the initiation mechanism of the polymerization, a kinetic investigation was also undertaken of the decomposition of TMT in the presence of p-substituted benzyl chlorides in DMF. The decomposition rate was first-order in TMT and first-order in p-substituents benzyl chloride. The decomposition rate also increased with the σ constants of substituents as electron-releasing groups were introduced. On the basis of the results, the initiation mechanism for the polymerization was discussed. 相似文献
59.
Drug adherence is one of the important aspects in caring for patients with allergic rhinitis. To improve clinical efficacy of early treatment for Japanese cedar pollinosis (JCP), we evaluated the effect of drug adherence on patients' outcomes. Patients were randomly selected from 16 ENT clinical sites in Osaka and Wakayama between February 24 and March 8, 2003 (peak pollen season). Efficacy was assessed using patients' ratings of nasal and ocular symptoms and overall assessment in their condition compared with previous season ones. Costs include direct costs of the drugs used for treatment to JCP from January to February. Five hundred one patients taking early treatment were enrolled. Compared to low adherence patients, those who reported higher level of adherence significantly improved overall health condition, and achieved better symptom relief of rhinorrhea and nasal congestion. In multiple logistic regression analysis, the following factors were independent risk factors for low adherence: student (p=0.002), using OTC medications (p=0.006), and short-duration of medication (p=0.001). Low costs were also risk factor for low adherence. We conclude that taking medications for JCP for 22-28 days is the best way to enhance patients' outcomes. 相似文献
60.
Y Inoue T Fukui M Shirahama 《Rinsho byori. The Japanese journal of clinical pathology》1992,40(1):42-48
This study was designed to evaluate signs and stat tests as an indicator of lower urinary tract infection in female subjects with urogenital complaints at an out-patient clinic. Of various symptoms including hematuria, pollakiuria, dysuria, urinary retention, and micturition pain, pain during micturition was present in 48% of 25 patients with urinary tract infections and in 4% of 27 patients without urinary tract infections, and was the sign with the highest positive predictive value. Comparison and discrimination of the infection and non-infection groups using a single laboratory valuable yielded significant F-statistics for urinary leukocyte esterase (14.5) and leukocyte count in urinary sediment (31.1), and revealed large Mahalanobis' distances for the same variables. Multivariate analysis using a discriminant function of categorical data (Hayashi's Suryoka type 2) revealed that combining occult blood with leukocyte esterase in the urine or combining red cell count with leukocyte count in sediment did not yield substantially smaller misclassification error than did leukocyte esterase alone or leukocyte count alone. It was concluded that neither urinary occult blood nor red cell count in sediment contribute substantially to the prediction of urinary tract infection. For the purpose of detecting urinary tract infection among outpatients, a receiver-operating characteristic analysis demonstrated that the optimal cut-off point in sediment was 3 or more leukocytes per microscopic high power field (x 400). Urinary leukocyte esterase was found to have limitations for use in screening, because its optimal decision level is equivalent to trace esterase reading on the dipstick test. 相似文献