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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Atsuo Ogura Toshihiko Asano Junichiro Matsuda Minako Koura Masaro Nakagawa Hiroshi Kawaguchi Yutaka Yamaguchi 《Virchows Archiv : an international journal of pathology》1990,417(3):223-228
Summary Glomerular lesions in hereditary nephrotic mice (ICGN strain) were investigated by electron microscopy. The glomeruli of unaffected animals, which appeared normal by light microscopy, had developed an ultrastructural change in the glomerular capillary basement membrane (GCBM). There was a partial thickening of the GCBM with bilaminar splitting of the lamina densa and an electron-dense fibrillar material exhibiting cross-striations. In affected animals, light microscopy revealed a marked thickening of GCBM and an increase of mesangial matrix without cellular proliferaton. By electron microscopy, multilaminar splitting of the lamina densa in the thickened GCBMs and fusion of the epithelial foot processes were observed. In some severely affected animals, immune complex deposition was found in GCBM, but little if any was observed in other animals. In the end, the glomeruli were globally sclerosed. Our findings suggest that initial structural abnormalities in GCBM may play an important role in the onset and development of the disease, though subsequent events such as immune complex deposition would modify the disease. 相似文献
992.
Kenji Naritomi Yoshinori Izumikawa Noriko Kinjo Chuken Miyagi Kiyotake Hirayama 《Journal of human genetics》1989,34(2):113-121
To identify the origin of a small inserted segment in ade novo 8p+ chromosome, an originally programmed computerized data-base for chromosomal aberration syndromes was utilized. The system selected 3q2 trisomy and 10q2 trisomy as candidates. As a result of a careful comparison of several high-resolution banding patterns among chromosomes 3, 10 and the inserted segment, her karyotype was disignated as: 46,XX,–8,+der(8), inv ins(8;3)(p21.1;q26.32q24)de novo. A small segment from 3q24 to 3q26.32 was trisomic, and invertedly inserted into the short arm of chromosome 8. This computerized database was considered to be useful for analyses of the smallde novo inserted chromosomal segment. 相似文献
993.
Orazio Gabrielli Anna Ficcadenti Giancarlo Fabrizzi Paolo Perri Antonio Mercuri Giovanni V. Coppa Pierluigi Giorgi 《American journal of medical genetics. Part A》1994,53(3):290-293
We report on a male infant with oral, facial, digital, and skeletal anomalies in association with severe psychomotor delay. This may represent a new oral-facial-digital syndrome. © 1994 Wiley-Liss, Inc. 相似文献
994.
Akagi M Inui K Nakajima S Shima M Nishigaki T Muramatsu T Kokubu C Tsukamoto H Sakai N Okada S 《Journal of human genetics》2000,45(1):60-62
Fanconi-Bickel syndrome (FBS), or glycogen storage disease type XI, is a rare autosomal recessive disorder characterized
by hepatorenal glycogen accumulation, Fanconi nephropathy, and impaired utilization of glucose and galactose. Recently, this
disease was elucidated to link mutations in the glucose transporter 2 (GLUT2) gene. Only three mutations in three FBS families have been reported. Therefore, it is important to elucidate mutations in
the GLUT2 gene in FBS by answering the question of whether the syndrome is a single gene disease. In this report, we describe two patients
in two unrelated families clinically diagnosed with FBS. No mutation in the entire protein coding region of the GLUT2 gene was detected in patient 1, which suggested that no mutation existed in the GLUT 2 gene, or that some mutations had affected the expression of the GLUT 2 gene. In patient 2, a novel homozygous nonsense mutation (W420X, Trp at codon 420 to stop codon) was detected. These results
support the correlation between GLTU2 gene mutation and FBS syndrome. However, many patients must be analyzed to determine whether other genes are involved in
FBS.
Received: July 16, 1999 / Accepted: September 3, 1999 相似文献
995.
Terada T Matsunaga Y Maeta H Endo K Horie S Ohta T 《Virchows Archiv : an international journal of pathology》1999,435(6):606-611
We report an autopsy case of mixed ductal-endocrine carcinoma of the pancreas presenting as gastrinoma with Zollinger-Ellison
syndrome. A 38-year-old Japanese male was found to have Zollinger-Ellison syndrome and pancreatic gastrinoma, and gastrectomy
and resection of the pancreatic tumor were performed. However, hypergastrinemia persisted, and the patient died of disseminated
carcinomatosis at 62 years of age, 24 years after the onset of Zollinger-Ellison syndrome. At autopsy, the main tumor was
present in the residual pancreas, and metastases were noted in many organs. In the pancreas and other organs, ductal and endocrine
carcinoma areas were mixed and there was a gradual transition between the two. No acinar differentiation was noted. The ductal
elements were positive for mucins and carcinoembryonic antigen but negative for neuroendocrine markers, while endocrine elements
were positive for chromogranin A and synaptophysin and to a lesser extent for gastrin, but negative for mucins and carcinoembryonic
antigen. The ductal elements comprised about 30% of the tumor cells, and endocrine elements 70%. According to the revised
World Health Organization classification, our case was diagnosed as mixed ductal-endocrine carcinoma. Our case is rare because
the tumor manifested as gastrinoma with Zollinger-Ellison syndrome and the patient survived for 24 years. To the best of our
knowledge, no such case has been reported. Our case suggests that pancreatic endocrine tumors may evolve into mixed ductal-endocrine
carcinomas.
Received: 14 April 1999 / Accepted: 7 July 1999 相似文献
996.
Ulrike Fuhrmann Karsten Parczyk Michael Klotzbücher Helmut Klocker A. C. B. Cato 《Journal of molecular medicine (Berlin, Germany)》1998,76(7):512-524
Antihormones are by definition antagonists of steroid hormone action. They interact with the ligand binding domains of steroid
hormone receptors and competitively inhibit the action of the receptors by mechanisms that are not quite understood. In certain
cases antihormones also exhibit agonistic activity especially in connection with certain naturally occurring receptor mutants.
These observations together with findings of indiscriminate interaction of antihormones with several classes of steroid receptors
have necessitated a search of more effective and reliable antihormones. Recent advances in the resolution of the crystal structure
of the ligand binding domains of certain members of the steroid receptor family and identification of non-liganded activation
of steroid receptors have produced considerable information that can be harnessed into a fruitful search for a new generation
of antihormones.
Received: 19 June 1997 / Accepted: 10 October 1997 相似文献
997.
Petros M Pavlopoulos Anastasia E Konstantinidou Emmanuel Agapitos Panagiotis Davaris 《Clinical genetics》1998,54(6):512-516
Roberts syndrome (RS) is a rare autosomal recessive disorder characterized primarily by symmetric reduction anomalies of all limbs, growth retardation and craniofacial abnormalities. Most RS patients are reported to present a typical abnormality of their constitutive heterochromatin, accompanied by abnormal cytological growth characteristics. We present an extremely severe case of an RS fetus, karyotypically documented, with a clinical presentation including growth deficiency, tetraphocomelia, frontal meningocele, craniofacial abnormalities and penile enlargement with hypospadias. Nuclear morphometrical analysis in tissues of various organs revealed a reduced nuclear size in RS as compared to normal controls, and statistically significant differences in morphometric parameters related to the nuclear shape. Immunohistochemical study of the same organs showed a reduced expression of proliferating cell nuclear antigen in the presented case, thus indicating a decreased cell proliferation rate in RS. Our results reconfirm previously reported findings in cultured fibroblasts of RS cases, thereby reinforcing on a histologic level, the hypothesis that reduced cell proliferation may be involved in the growth retardation and the reduction abnormalities observed in RS. 相似文献
998.
Cytogenetic and molecular cytogenetic studies of a case of interstitial deletion of proximal 15q 总被引:3,自引:0,他引:3
Vijay Tonk Herman E. Wyandt Peter Osella James Skare Bai Lin Wu Bassem Haddad Aubrey Milunsky 《Clinical genetics》1995,48(3):151-155
A 4-month-old child with multiple anomalies was determined to have an interstitial deletion of chromosome 15, i.e., del(15) (q12q14). The deletion appears not to be a typical deletion of 15q12 such as seen in Angelman and Prader-Willi syndromes, but appears to be more distal, involving either loss of all of 15q12 and part of 15q14, or part of 15q12 and most of 15q14. In either case, 15q13 is missing. Fluorescent in situ hybridization with probes for 15 centromere (D15Z), pericentromeric satellite sequences (D15Z1), and chromosome 15 painting probes shows the deleted chromosome to involve only 15 and no other acrocentric chromosome. Hybridization with probes for the AS and PWS loci (D15S11 and GABAB3, Oncor) show both sites to be intact in the deleted 15. The case is compared with two other reports with overlapping interstitial deletions of proximal 15q, neither of which shows typical features of Angelman or Prader-Willi syndromes. 相似文献
999.
Sonia Ehrlich Tania Bustos Inder J. Paika Aubrey Milunsky John M. Opitz 《American journal of medical genetics. Part A》1983,15(2):261-263
Some variation in the phenotype of patients with dup(18q) is recognized. Our patient has the phenotype described for dup(18qter). 相似文献
1000.
Theodore Kushnick Thomas G. Irons John E. Wiley Elizabeth A. Gettig Kathleen W. Rao Susan Bowyer John M. Opitz James F. Reynolds 《American journal of medical genetics. Part A》1987,28(3):567-574
Two white females, age 2 1/2 and 33 years, respectively, were investigated because of severe mental retardation associated with neurologic abnormalities, coarse face, and soft tissue syndactyly involving upper and lower limbs. Each had cytogenetic findings of a mosaic variant of Ullrich-Turner syndrome with X ring chromosome in peripheral lymphocyte and skin fibroblasts. Early X replication occurred in one-third of the X ring chromosomes; there was no evidence for X-autosome translocation involving either X and an autosomal duplication; results of studies for fragility of the X chromosomes were unremarkable. In situ hybridization with an X centromere probe was positive for the ring. To our knowledge, the unusual constellation of cytogenetic, physical, and mental findings seen in these 2 individuals has not been reported previously. 相似文献