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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.
Control of HIV-1 replication by RNA interference 总被引:15,自引:0,他引:15
993.
PCR primers specific for the recently described antimicrobial resistance-associated Escherichia coli clonal group A (CGA), a widespread cause of drug-resistant urinary tract infections in the United States, were devised on the basis of a novel single-nucleotide polymorphism identified within the housekeeping gene fumC, i.e., C288T. In comparison with two reference PCR-based fingerprinting methods, ERIC2 PCR and random amplified polymorphic DNA (RAPD) analysis, a PCR assay incorporating the new primers provided 100% sensitivity and 100% specificity for the detection of CGA among 138 diverse clinical and reference E. coli isolates. E. coli reference (ECOR) strain 47 was shown to be a member or a close relative of CGA (by ERIC2 PCR and RAPD analysis, respectively) and yielded a positive assay result. The new CGA-specific PCR assay, which exhibited interlaboratory reproducibility and stability under various experimental conditions, should allow the rapid and specific detection of CGA by any laboratory equipped for diagnostic PCR. 相似文献
994.
Hong KE Ock SM Kang MH Kim CE Bae JN Lim MK Suh CH Chung SJ Cho SC Lee JS 《Journal of Korean medical science》2002,17(4):530-536
Neuropathological deficits are an etiological factor in Tourette syndrome (TS), and implicate a network linking the basal ganglia and the cerebrum, not a particular single brain region. In this study, the volumes of 20 cerebral and cerebellar regions and their symmetries were measured in normal boys and TS boys by brain magnetic resonance imaging. Brain magnetic resonance images were obtained prospectively in 19 boys with TS and 17 age-matched normal control boys. Cerebral and cerebellar regions were segmented to gray and white fractions using algorithm for semi-automated fuzzy tissue segmentation. The frontal, parietal, temporal, and the occipital lobes and the cerebellum were defined using the semiautomated Talairach atlas-based parcellation method. Boys with TS had smaller total brain volumes than control subjects. In the gray matter, although the smaller brain volume was taken into account, TS boys had a smaller right frontal lobe and a larger left frontal lobe and increased normal asymmetry (left>right). In addition, TS boys had more frontal lobe white matter. There were no significant differences in regions of interest of the parietal, temporal, or the occipital lobes or the cerebellum. These findings suggest that boys with TS may have neuropathological abnormalities in the gray and the white matter of the frontal lobe. 相似文献
995.
Bong Hyo Lee Rong Jie Zhao Jin Young Moon Seong Shoon Yoon Jung-Ae Kim Heeduk An Young Kyu Kwon Meeyul Hwang Seong Hun Choi Insop Shim Bong Hyun Kim Chae Ha Yang 《Neuroscience letters》2008
In our previous study we demonstrated that acupuncture at Shenmen (HT7) points suppressed a decrease of accumbal dopamine (DA) release in ethanol-withdrawn rats. Furthermore, here we found that it inhibited behavioral withdrawal signs of ethanol. In an effort to better understand the mechanisms underlying this inhibition, the potential role of GABA receptor system in acupuncture was investigated. Male Sprague–Dawley rats were treated with 3 g/kg/day of ethanol (20%, w/v) or saline by intraperitoneal injection for 21 days. Following 48 or 72 h of ethanol withdrawal, acupuncture was applied at bilateral HT7 for 1 min. The selective GABAA antagonist bicuculline and the selective GABAB antagonist SCH 50911 were injected intraperitoneally 20 min before acupuncture, respectively. Importantly, suppressive effects of acupuncture on DA deficiency were completely abolished by SCH 50911, but not by bicuculline, whereas ameliorating effects of acupuncture on ethanol withdrawal syndrome were completely blocked either by SCH 50911 or bicuculline. These results suggest that acupuncture at specific acupoint HT7 may normalize the DA release in the mesolimbic system and attenuate withdrawal syndrome through the GABAB receptor system in ethanol-withdrawn rats. 相似文献
996.
Traditionally, radiology has been conceived as a support department providing patient scanning services to the other clinical
departments in a hospital. However, recent advancements in networking technology and related information systems such as picture
archiving and communication system (PACS) and radiology information system (RIS) provide new opportunities for inventing different
types of diagnostic imaging businesses such as teleradiology. In this article, we examined the business processes of currently
operating imaging centers and proposed a prototype of an information system that can facilitate their workflows in a more
efficient way. The principal component of our proposed system is a report management module built on extensible markup language
(XML) technologies that allows much flexibility and convenience for both imaging technicians and radiologists. 相似文献
997.
I. C. Park S. Y. Lee D. G. Jeon J. S. Lee C. S. Hwang B. G. Hwang S. H. Lee W. S. Hong S. I. Hong 《Journal of Korean medical science》1996,11(2):144-148
Cathepsin L is a kind of cystein proteases which are known to facilitate the invasion and metastasis of tumor cells by degrading the components of basement membrane and extracellular matrix. This study was undertaken to investigate the expression of cathepsin L by Northern blot analysis with radiolabeled cDNA specific for cathepsin L in six normal tissues, two osteosarcoma cell lines, MG-63 and Saos-2, six primary bone tumors and six metastatic bone tumors. In six normal tissues, the highest level of cathepsin L was expressed in liver with the descending order of liver > lung > thymus > ovary > kidney > esophagus. One of the two osteosarcoma cell lines established from the primary sites expressed a high level of cathepsin L mRNA. Out of six primary bone tumors, three (50%) expressed cathepsin L mRNA, while all (100%) of six metastatic bone tumors expressed the mRNA. These results demonstrating the higher frequency of expression of cathepsin L in metastatic bone tumors suggest that cathepsin L may participate in tumor invasion and metastasis. 相似文献
998.
999.