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991.
We have identified a novel mutation within the linker L12 region of keratin 5 (K5) in a family with the K?bner variant of epidermolysis bullosa simplex. The pattern of inheritance of the disorder in this family is consistent with an autosomal dominant mode of transmission. Affected individuals develop extensive and generalized blistering at birth or early infancy but in later years clinical manifestations are largely confined to palmoplantar surfaces. Direct sequencing of polymerase chain reaction products revealed a T to C transition within codon 323 of K5 in affected individuals, resulting in a valine to alanine substitution of the seventh residue within the L12 linker domain. This mutation was not observed in unaffected family members or in 100 K5 alleles of unrelated individuals with normal skin. The other critical regions of K5 and K14 were unremarkable in this family except for common polymorphisms that have been previously described. The valine at position 7 of the L12 domain is absolutely conserved in all type II keratins, and in other intermediate filament subunits as well, which suggests that this residue makes an important contribution to filament integrity. Secondary structure analysis revealed that alanine at this position markedly reduces both the hydrophobicity and the beta-sheet nature of the L12 domain. This is the first report of a mutation at this position in an intermediate filament subunit and reinforces the importance of this region to filament biology. 相似文献
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Bacteria of genus Klebsiella were found to possess group-specific antigens of ABO system. Representatives of conditionally pathogenic species, K. rhinoscleromatis, K. pneumoniae, K. ozaenae, K. oxytoca, contain 9.4 to 38% of the antigens. In the process of interaction of plant organisms and Klebsiella, which passed three times in green tomato fruits, the latter have been found to influence some biological features of the bacteria which is manifested in the loss of the mimicry antigens by a considerable part of the strains as well as in developing capsules by some capsule-free variants of klebsiellae. 相似文献
995.
H Ren RS Poston RH Hruban WA Baumgartner KL Baughman GM Hutchins 《Canadian Metallurgical Quarterly》1993,6(4):402-407
Several aspects of giant cell myocarditis remain controversial, including the natural history of the disease and the nature of the giant cells. We have observed three patients who had long survival with chronic active giant cell myocarditis. The first patient was a 59-yr-old female who had a 10-yr history of complete heart block which was found at autopsy to have been caused by giant cell myocarditis. The second patient is a 36-yr-old female who received a heart transplant 5 yr after a biopsy proven episode of active myocarditis, and examination of the explanted heart revealed giant cell myocarditis. The third patient was a 41-yr-old male who received a heart transplant 2 yr after developing progressive heart failure, and the explanted heart had giant cell myocarditis. On immunohistochemical study of the three hearts, the giant cells stained with the macrophage markers lysozyme and KP-1 (CD-68). Staining of the same cells with desmin and actin was focally positive in a punctate pattern, correlating with the ultrastructural presence of myofibrils within giant cell phagolysosomes. The associated lymphocytic infiltrate stained primarily for the T-cell markers CD-3, CD-45RO, and CD-43 whereas only a few of the lymphocytes stained with the B-cell marker CD-20. The long histories of cardiac dysfunction in the three patients show that giant cell myocarditis may have a protracted course. The morphologic studies show that the giant cells are of histiocytic origin but can contain phagocytosed components of myocytes, observations that may account for the controversy surrounding the nature of the giant cells in giant cell myocarditis. 相似文献
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PURPOSE: To examine the blastocyst formation rates of day-2 fertilized oocytes. METHODS: A retrospective study of the outcomes/blastocyst formation of day-2 fertilized oocytes was undertaken. RESULTS: Fertilization rates of day-1 and -2 oocytes by intra-cytoplasmic sperm injection were similar. The development frequencies to four cells were similar. However, the blastulation rates were significantly lower from the day-2 fertilized eggs. The fertilization rates from day-2 conventional in vitro fertilization reinsemination were lower than the fertilization rates of day-1 oocytes. The blastulation rates from day-2 fertilized eggs were also lower than the rates from day-1 fertilized eggs in the in vitro fertilization group. CONCLUSIONS: Fertilization is not a good indicator to predict the viability of fertilized oocytes. Day-2 fertilized oocytes had significantly lower blastocyst formation rates than the rates from day-1 fertilized oocytes. 相似文献
1000.
GM Mullen MA Silver K Malinowska CE Lawless RC Lichtenberg PC Barath PJ O'Keefe JA Robinson V Yeldandi 《Canadian Metallurgical Quarterly》1998,30(8):4110-4112
The presented data show the combined sequential use of i.v. G for 14 days followed by PO G for 90 days is a much more effective prophylaxis for CMVD after heart transplantation than use of i.v. G for 14 days followed by PO A for 90 days. A need for hospitalization due to CMVD is significantly reduced by this new strategy. The follow-up in group II is shorter than in group I but is now at least 6 months in group II, without any new cases in the first 6 months after cardiac transplantation. Some currently unknown adverse effect of prolonged PO G, which may be present, is not identified in this analysis. 相似文献