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991.
Pulmonary pathological features in coronavirus associated severe acute respiratory syndrome (SARS) 总被引:5,自引:0,他引:5
Tse GM To KF Chan PK Lo AW Ng KC Wu A Lee N Wong HC Mak SM Chan KF Hui DS Sung JJ Ng HK 《Journal of clinical pathology》2004,57(3):260-265
BACKGROUND: Severe acute respiratory syndrome (SARS) became a worldwide outbreak with a mortality of 9.2%. This new human emergent infectious disease is dominated by severe lower respiratory illness and is aetiologically linked to a new coronavirus (SARS-CoV). METHODS: Pulmonary pathology and clinical correlates were investigated in seven patients who died of SARS in whom there was a strong epidemiological link. Investigations include a review of clinical features, morphological assessment, histochemical and immunohistochemical stainings, ultrastructural study, and virological investigations in postmortem tissue. RESULTS: Positive viral culture for coronavirus was detected in most premortem nasopharyngeal aspirate specimens (five of six) and postmortem lung tissues (two of seven). Viral particles, consistent with coronavirus, could be detected in lung pneumocytes in most of the patients. These features suggested that pneumocytes are probably the primary target of infection. The pathological features were dominated by diffuse alveolar damage, with the presence of multinucleated pneumocytes. Fibrogranulation tissue proliferation in small airways and airspaces (bronchiolitis obliterans organising pneumonia-like lesions) in subpleural locations was also seen in some patients. CONCLUSIONS: Viable SARS-CoV could be isolated from postmortem tissues. Postmortem examination allows tissue to be sampled for virological investigations and ultrastructural examination, and when coupled with the appropriate lung morphological changes, is valuable to confirm the diagnosis of SARS-CoV, particularly in clinically unapparent or suspicious but unconfirmed cases. 相似文献
992.
间变性大细胞淋巴瘤形态学及免疫表型观察 总被引:1,自引:1,他引:1
目的:探讨间变性大细胞淋巴瘤(ALCL)的形态学和免疫表型特征。方法:对6例ALCL和2例弥温性大B细胞淋巴瘤(DLBCL)进行形态学和免疫组织化学染色(ABC法)观察。结果:6例ALCL中,普通型2例、淋巴组织细胞型2例、ALK-变型2例,均可见单型性或多形性的标志性大细胞。普通型和ALK-变型大细胞沿淋巴窦内生长,而淋巴组织细胞型大细胞则呈散在分布;2例DLBCL形态上颇似ALCL;6例ALCL均为T细胞,CD30+,儿童患者共同表达ALK+和EMA+,年长者则ALK-和EMA-。2例DLBCL均为B细胞,ALK+、CD30-和EMA-。结论:不论何型ALCL,均可见CD30+的标志性大细胞,淋巴窦内生长多见于普通型和ALK-变型。ALCK均为T细胞,儿童常有ALK和EMA共同表达,年长者则ALK和EMA-。DLBCL的免疫表型不同于ALCL。 相似文献
993.
994.
Huang W Sher YP Delgado-West D Wu JT Peck K Fung YC 《Annals of biomedical engineering》2001,29(7):535-551
The remodeling of the pulmonary arterial tissue in response to a step change of the oxygen concentration in the gas in which a rat lives was recorded as function of time and function of O2 concentration. Three steps of changing from 20.9% to 17.2%, 13.6%, and 10% O2 were imposed. Earlier work in our laboratory has shown that pulmonary arterial tissue remodeling is significant in the first 24 h after a step change of oxygen tension. Hence we made measurements in this period. Furthermore, data were obtained for tissue remodeling of circumferential and axial lengths of the pulmonary arteries. We recorded the activities of gene expressions in the lung tissues by microarray, determined the dose response curves of gene expression in the homogenized whole lungs with respect to four levels of O2 concentration, and obtained the time courses of gene expression in the lung parenchyma in 30 days after a step decrease of O2 concentration from 20.9% to 10%. We would like to suggest that the correlation of gene expression with physiological function parameters, i.e., time, O2 tension, blood pressure, opening angle, wall thicknesses, etc., is the way to narrow down the search for specific genes for specific physiological functions. © 2001 Biomedical Engineering Society.
PAC01: 8719Uv 相似文献
995.
Yu-Li Liu Cathy Shen-Jang Fann Chih-Min Liu Jer-Yuarn Wu Shuen-Iu Hung Hung-Yu Chan Jiahn-Jyh Chen Chin-Yu Lin Shih-Kai Liu Ming H Hsieh Tzung-Jeng Hwang Wen-Chen Ouyang Chun-Ying Chen Jin-Jia Lin Frank Huang-Chih Chou Ching-Mo Chueh Wei-Ming Liu Ming-Min Tsuang Stephen V Faraone Ming T Tsuang Wei J Chen Hai-Gwo Hwu 《American journal of medical genetics. Part B, Neuropsychiatric genetics》2006,(4):418-420
Several studies have suggested that the regulator of G-protein signaling 4 (RGS4) may be a positional and functional candidate gene for schizophrenia. Three single nucleotide polymorphisms (SNP) located at the promoter region (SNP4 and SNP7) and the intron 1 (SNP18) of RGS4 have been verified in different ethnic groups. Positive results have been reported in these SNPs with different numbers of SNP combinatory haplotypes. In this study, these three SNP markers were genotyped in 218 schizophrenia pedigrees of Taiwan (864 individuals) for association analysis. Among these three SNPs, neither SNP4, SNP7, SNP18 has shown significant association with schizophrenia in single locus association analysis, nor any compositions of the three SNP haplotypes has shown significantly associations with the DSM-IV diagnosed schizophrenia. Our results fail to support the RGS4 as a candidate gene for schizophrenia when evaluated from these three SNP markers. 相似文献
996.
Jihai Xu Jing Wu Xiaofeng Teng Libing Cai Huizong Yuan Xiaokun Chen Mu Hu Xin Wang Ning Jiang Hong Chen 《American journal of medical genetics. Part A》2020,182(9):2117-2123
Polydactyly and syndactyly are digital abnormalities in limb‐associated birth defects usually caused by genetic disorders. In this study, a five‐generation Chinese pedigree was found with triphalangeal thumb polysyndactyly syndrome (TPTPS), showing an autosomal dominant pattern of inheritance. We utilized linkage analysis and whole genome sequencing (WGS) for the genetic diagnosis of this pedigree. Linkage analysis was performed using a genome‐wide single nucleotide polymorphism (SNP) chip and three genomic regions were identified in chromosomes 2, 6, and 7 with significant linkage signals. WGS discovered a copy number variation (CNV) mutation caused by a large duplication region at the tail of chromosome 7 located in exons 1–5 of the LMBR1 gene, including the zone of polarizing activity regulatory sequence (ZRS), with a length of approximately 180 kb. A real‐time polymerase chain reaction (PCR) assay confirmed the duplication. The findings of our study supported the notion that large duplications including the ZRS caused TPTPS. Our study showed that linkage analysis in combination with WGS could successfully identify the disease locus and causative mutation in TPTPS, which could help elucidate the molecular mechanisms and genotype–phenotype correlations in polydactyly. 相似文献
997.
M. T. Lin Y. C. Chen P. J. Chen Y. C. Yang J. L. Tang J. M. Wu S. E. Chuang C. S. Yang 《Archives of virology》1996,141(2):219-229
Summary Three major types of HTLV-I had been proposed, the Melanesian type, the Zairian type, and the cosmopolitan type, which was further divided into subtypes A, B and C, according to the phylogenetic tree constructed from LTR sequences of current HLTV-I isolates. In this study, the envelope gene sequences of HTLV-I from 9 Taiwanese were analyzed. Based on the phylogenetic tree constructed by unweighed pair group method and the sequence homology analysis by GCG computer programs, the envelope gene sequences of HTLV-I proviruses from these 9 Taiwanese belonged to subtype A or subtype B of the cosmopolitan type and were closely related to HTLV-I from Japan. Twelve subtype-specific nucleotide variations were deduced from the comparison of complete or partial envelope gene sequences of 16 HTLV-I isolates of known subtypes as well as those of 9 Taiwanese. These data provided the basis for subtyping the cosmopolitan type of HTLV-I by amplification of envelope gene sequences and restriction fragment length polymorphism studies. A more extensive survey based upon this proposal was warranted. 相似文献
998.
999.
Chee-Kin Hui Eva Lau Helen Wu Alexander Monto Michael Kim John M Luk George K K Lau Teresa Lyn Wright 《Journal of clinical virology》2006,35(2):185-192
Occult hepatitis B virus (HBV) infection in individuals without hepatitis B surface antigen (HBsAg) can be identified in hepatitis C virus (HCV) infected patients. However, its role in fibrosis progression remains uncertain. This retrospective study compared the fibrosis progression (defined as fibrosis progression by at least one stage) and progression to severe fibrosis (fibrosis stage 3 or 4) in HCV patients with occult HBV infection. Occult HBV infection was diagnosed by the detection of HBV DNA in the serum of 74 consecutive anti-HCV positive patients by PCR. Thirty-one patients (41.9%) had occult HBV infection. All 74 patients had a median of 2 (range 2-3) liver biopsies. The median time between the first and last liver biopsy was 57.7 (range 15.0-132.8) months. Eleven of the 31 patients with occult HBV infection compared with 12 of the 43 patients without occult HBV infection had fibrosis progression (35.5% versus 27.9%, respectively, p=0.608). Six of the 31 patients with occult HBV infection compared with 8 of the 43 patients without occult HBV infection developed severe fibrosis (19.4% versus 18.6%, respectively, p=0.946). In conclusion, chronic HCV patients with occult HBV co-infection does not seem to progress more than patients without occult HBV infection. However, more large-scale studies are needed before a definite conclusion can be obtained. 相似文献
1000.