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Hereditary coproporphyria (HCP) is an acute hepatic porphyriawith autosomal dominant inheritance, but with a variable degreeof clinical expression. Molecular cloning, sequencing and expressionof the defective gene for coproporphyrinogen oxidase (CPO) ina patient with HCP were carried out. Enzyme assays revealedthat CPO activity in EBV-transformed lymphoblastoid cells fromthe proband and one of her sisters was  相似文献   
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We investigated the presence of osteocyte apoptosis in the necrotic trabeculae of the femoral head of spontaneously hypertensive rat (SHR) using the in situ nick end labeling (TUNEL) method and transmission electron microscopy. The occurrence of osteonecrosis and ossification disturbance was significantly higher in SHR compared with Wistar Kyoto (WKY) rats, and Wistar (WT) rats used as control animals (P < 0.01). A high population of TUNEL positive osteocytes was detected mainly in 10- and 15-week-old SHRs. Sectioned examination of the femoral head of SHRs and WKY rats by electron microscopy revealed apoptotic cell appearances such as aggregation of chromatin particles and lipid formation. In contrast, a positive reaction was significantly lower in osteocytes in the femoral heads of WT rats (P < 0.01). Our results indicate that apoptosis forms an important component of the global pathologic process affecting the femoral head of SHR, which leads to osteonecrosis in this region.  相似文献   
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T Kondo 《Arerugī》1969,18(1):81-85
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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   
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We report a case of isolated unilateral absence of a pulmonary artery. The first clinical symptom that was manifested in the patient was recurrent hemoptysis, and subsequent angiography revealed that the main pulmonary artery was absent in the right lung, which was being fed only from the systemic circulation. Right pneumonectomy was performed, and neither the main pulmonary artery nor its remnant was detected in the resected right lung. Histologically, there were many muscular vessels in the resected lung, with intimal proliferation, or with plexiform-like lesions. The alveolar septum was moderately thickened and alveolar capillary vessels were dilated. We examined the alveolar capillary endothelial cells of the resected lung for immunoreactivity to thrombomodulin (TM) and von Willebrand factor (vWF). The endothelial cells were negative for TM and positive for vWF, while in the normal lung control group, these cells were positive for TM and negative for vWF. We considered that the hemodynamics of the systemic circulation in the resected lung caused the alteration of immunohistochemical characteristics in alveolar capillary endothelial cells.  相似文献   
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Superior cervical ganglia of rats were centrifuged at 40,000 rpm (160,500 g) for 1 h at 4 degrees C. Most neuronal somata exhibit a minor centripetal domain free of organelles and a major centrifugal domain rich in organelles. The former is occupied by numerous fine granules having low electron density unlike ribosomes in epoxy sections stained with uranium and lead, and is occupied by a meshwork of microtrabecular or filamentous elements similar to that of the centrifugal domain as well as that of the normal cells in PEG (polyethylene glycol)-processed embedment-free sections without staining. The latter centrifugal domain contains regular cell organelles except for neurofilaments without stratification. All the organelles are suspended in the meshwork of microtrabecular or filamentous elements. In immunolight microscopy, NFPs (neurofilament proteins) are confined to the centripetal domain. In immunoelectron microscopy using ultrathin cryosections and the protein A-gold labeling, numerous gold-particles for NFPs were deposited randomly in the centripetal cytoplasmic domain without long linear alignment. In the PEG sections the gold-labelings for NFPs are randomly deposited on portions of the microtrabecular strands in the centripetal domain. After incubation of the centrifuged ganglia in the anterior eye chamber overnight, NFPs-immunoreactivity appears again diffusely throughout the entire cytoplasm of all neuronal somata in immunolight microscopy. The organelle-free domain of the cytoplasm is no longer visible in electron microscopy. The present findings are discussed in relation to the state of the cytoplasmic soluble proteins and the reality of the microtrabecular or filamentous elements in the cytoplasm.  相似文献   
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