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61.
62.
Deletion of a single chromosome band 4q26 in a malformed girl: exclusion of Rieger syndrome associated gene(s) from the 4q26 segment. 下载免费PDF全文
T Motegi K Nakamura T Terakawa A Oohira K Minoda K Kishi Y Yanagawa H Hayakawa 《Journal of medical genetics》1988,25(9):628-630
We report a malformed girl with a single chromosome band deletion of 4q26 in peripheral lymphocytes. This patient is the fourth case reported with an interstitial deletion involving 4q26 and has the smallest deletion of those reported. Deletion mapping indicates that psychomotor retardation, coloboma, prominent forehead, epicanthus, broad based nose, and broad, thin upper lip are associated with monosomy 4q26, and that gene(s) associated with Rieger syndrome can be excluded from the 4q26 segment. 相似文献
63.
Akira Uehara Kiyoko Uehara Koichi Ogawa 《Anatomical record (Hoboken, N.J. : 2007)》1994,240(1):141-147
Background: The presence of efferent fibers in the anteromedial eye of liphistiid spiders kept in natural daily cycles of illuminance has been reported. However, this report is limited to innervation by the efferent fiber and daily rhabdomal changes, and there have been no detailed ultrastructural accounts of the eye. Methods: The fine structure of this eye was examined by electron microscopy. Results and conclusions: The eye consists of a cornea, a lens, a vitreous body, and a retina. The retina contains 13 or 14 receptor cells and glial cells. The rhabdoms are distal to the nuclei of the receptor cells. In the distal region of the receptive segment, the rhabdomeres lie in the center of the cell. In the middle region, anisomorphic rhabdoms formed by microvilli from adjacent cells are at the cell periphery. In the proximal region, the rhabdomeres are situated in the center of the cell. The ocellar nerve of the eye runs toward the protocerebrum and enters the posterior part of the first optic ganglion of the secondary eyes. Pigmented cells and nonpigmented cells are observed. The pigmented cells are located in the most lateral of the eye and cover the whole eye. The nonpigmented cells are located in the receptor cell bodies and extend to the origin of the ocellar nerve. They wind to form capillaries filled with electron-dense material. These structures are discussed in comparison with those of other spiders and other chelicerates. © 1994 Wiley-Liss, Inc. 相似文献
64.
Yukio Nishimoto Tsukasa Iwahashi Toru Nishihara Hiroyuki Katayama Koichi Kueibayashi Toshihiko Takao Koji Saito 《Pathology international》1987,37(1):155-166
An autopsy case of hepatitis associated aplastic anemia was presented. A 58-year-old Japanese female with non-A, non-B hepatitis was admitted on August 2, 1983. Moderate grade of fever and hemorrhagic diathesis appeared on September 16, when hepatitis was evaluated as being under resolving. The peripheral blood and bone marrow findings were consistent with aplastic anemia. Since infection was suggested by increased levels of serum gamma-globulin and CRP, treatment with antibiotics as well as prednisolone and blood transfusion was initiated. Since September 21, gradual tenderness and edema on the right lower abdominal wall appeared. She died on October 3.
On postmortem examination, systemic plasmacytosis with lymphadenopathy and septic monilial infection was revealed. Numerous plasma cells were atypical, but were immunohistochemically proved to be polyclonal. The bone marrow showed a massive and diffuse plasma cell proliferation with extremely scarce myeloid cells and megakaryocytes. There was a large granulomatous lesion with monilial infection in the wall of the ileocecum. By these findings, systemic plasmacytosis was suspected to be due to chronic monilial infection.
The pathogenesis of systemic plasmacytosis in aplastic anemias and in other diseases were discussed with relation to the present case. 相似文献
On postmortem examination, systemic plasmacytosis with lymphadenopathy and septic monilial infection was revealed. Numerous plasma cells were atypical, but were immunohistochemically proved to be polyclonal. The bone marrow showed a massive and diffuse plasma cell proliferation with extremely scarce myeloid cells and megakaryocytes. There was a large granulomatous lesion with monilial infection in the wall of the ileocecum. By these findings, systemic plasmacytosis was suspected to be due to chronic monilial infection.
The pathogenesis of systemic plasmacytosis in aplastic anemias and in other diseases were discussed with relation to the present case. 相似文献
65.
Kazuhiko Yasuml Rong-Jun Guo Hiroyuki Hanai Hajime Arai Eizo Kaneko Hiroyuki Konno Selichi Takenoshita Koichi Hagiwara Haruhiko Sugimura 《Pathology international》1998,48(2):134-137
A new mutation in the serine-threonine klnase domain of the transforming growth factor β type II receptor (TGFpRII) was found in a case of diffuse, B cell non-Hodgkin's lymphoma of the stomach. A mfssense mutation (ACA to GCA, Thr to Ala) was detected In exon 5, and a wild type allele was also present. This Is the first naturally occurring mutation in the klnase domain of this gene identified in human primary lymphoma. The replication error at three loci was negative, and the poly A tract of exon 3, which is frequently a target of mismatch repair genes, was intact. Malignant lymphoma of B cell origin in the stomach Is an addition to an expanding catalogue of tumors with TGFβRII alterations, and the biological sequelae of the change in the functional domain and the clinical characteristics of the patient in this study are intriguing. 相似文献
66.
Clostridium sordellii phospholipase C: gene cloning and comparison of enzymatic and biological activities with those of Clostridium perfringens and Clostridium bifermentans phospholipase C 下载免费PDF全文
Karasawa T Wang X Maegawa T Michiwa Y Kita H Miwa K Nakamura S 《Infection and immunity》2003,71(2):641-646
The gene encoding Clostridium sordellii phospholipase C (Csp) was cloned and expressed as a histidine-tagged (His-tag) protein, and the protein was purified to compare its enzymatic and biological activities with those of Clostridium perfringens phospholipase C (Cpa) and Clostridium bifermentans phospholipase C (Cbp). Csp was found to consist of 371 amino acid residues in the mature form and to be more homologous to Cbp than to Cpa. The egg yolk phospholipid hydrolysis activity of the His-tag Csp was about one-third of that of His-tag Cpa, but the hemolytic activity was less than 1% of that of His-tag Cpa. His-tag Csp was nontoxic to mice. Immunization of mice with His-tag Cbp or His-tag Csp did not provide effective protection against the lethal activity of His-tag Cpa. These results indicate that Csp possesses similar molecular properties to Cbp and suggest that comparative analysis of toxic and nontoxic clostridial phospholipases is helpful for characterization of the toxic properties of clostridial phospholipases. 相似文献
67.
Length-tension relationships and contractile responses to agonists associated with cyclic nucleotide levels in aortas from atherosclerotic rabbits were studied. The same number of tissues from healthy rabbits was also studied. Diffuse lesions were produced by denudation of the vascular endothelium of rabbit aorta using a balloon catheter and then feeding these rabbits a high cholesterol diet for two months. Stretch-passive tension curves and length-active tension curves which developed in the presence of 60 mM KCl significantly shifted to the left. The altered length-tension relationships indicate a decreased distensibility in these strips and this is attributed to an enhanced accumulation of collagen. Dose-response curve analysis revealed a marked hypersensitivity to serotonin as indicated by greater pD2 values (negative logarithm of half maximum dose) than seen in the controls. In addition, the mean absolute values of the maximum contraction induced by serotonin and KCl were significantly higher than in the controls. Although cyclic AMP levels in the strips with a pathology were lower and cyclic GMP/cyclic AMP ratios were higher than the controls in the basal state, serotonin induced no marked alterations in the cyclic nucleotides levels in the strips from either the diseased or control rabbits. These mechanical and pharmacological alterations of atherosclerotic vessels may relate to clinical events such as coronary spasm. 相似文献
68.
Kakinuma C Suda K Shibutani Y 《Virchows Archiv : an international journal of pathology》1999,434(1):83-89
We investigated the time-course of changes in pancreatic fibrosis accompanied with pancreatitis in WBN/Kob rats. The areas
of fibrosis and fatty replacement were analysed morphometrically, and biochemical measurements of pancreatic and plasma prolyl
hydroxylase and of pancreatic collagenase were assessed. Male rats showed acute pancreatitis at 2–3 months of age, lesions
that later underwent a transition to widespread fibrosis. The fibrosis then decreased, and the fibrotic tissue was replaced
with adipose tissue. Morphometrically, the fibrotic area reached its maximal size when the rats were 4 months old, diminishing
thereafter. The fibrosis occurred mainly in the intralobular space, and was principally attributable to type-III collagen.
Type-I collagen scarcely appeared throughout the experimental period. α-Smooth muscle actin appeared in and around myofibroblasts
that developed in an early stage and diminished later in accordance with the progressive manner of fibrosis. The plasma prolyl
hydroxylase level was higher in males than in females from 4 through 10 months of age. Pancreatic collagenase activity in
the males also increased during the same period. These findings suggest that pancreatic fibrosis in male WBN/Kob rats is affected
by the balance between prolyl hydroxylase and collagenase.
Received: 1 October 1998 / Accepted: 2 October 1998 相似文献
69.
Ohara-Nemoto Y Kishi K Satho M Tajika S Sasaki M Namioka A Kimura S 《Journal of clinical microbiology》2005,43(3):1405-1407
We studied the pheno- and genotypes of an oral Granulicatella elegans strain in comparison with those of a blood-derived isolate which caused infective endocarditis. The two isolates exhibited identical biochemical characteristics and had the same drug MICs. Their genotypes were indistinguishable, indicating that these were from the same clone. The transmission of G. elegans from the oral cavity thus should be noted as a possible cause of infective endocarditis. 相似文献
70.
Morita Y Nakata K Kim YH Sekino T Niihara K Ikeuchi K 《Bio-medical materials and engineering》2004,14(3):263-270
While only alumina is applied to all-ceramic joint prostheses at present, a stronger ceramic is required to prevent fracture and chipping due to impingement and stress concentration. Zirconia could be a potential substitute for alumina because it has high strength and fracture toughness. However, the wear of zirconia/zirconia combination is too high for clinical use. Although some investigations on composite ceramics revealed that mixing of different ceramics was able to improve the mechanical properties of ceramics, there are few reports about wear properties of composite ceramics for joint prosthesis. Since acetabular cup and femoral head of artificial hip joint are finished precisely, they indicate high geometric conformity. Therefore, wear test under flat contact was carried out with an end-face wear testing apparatus for four kinds of ceramics: alumina monolith, zirconia monolith, alumina-based composite ceramic, and zirconia based composite ceramic. Mean contact pressure was 10 MPa and sliding velocity was 40 mm/s. The wear test continued for 72 hours and total sliding distance was 10 km. After the test, the wear factor was calculated. Worn surfaces were observed with a scanning electron micrograph (SEM). The results of this wear test show that the wear factors of the both composite ceramics are similarly low and their mechanical properties are much better than those of the alumina monolith and the zirconia monolith. According to these results, it is predicted that joint prostheses of the composite ceramics are safer against break down and have longer lifetime compared with alumina/alumina joint prostheses. 相似文献