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81.
Radiation exposure is an occupational hazard for military personnel, some health care professionals, airport security screeners, and medical patients, with some individuals at risk for acute, high-dose exposures. Therefore, the biological effects of radiation, especially the potential for chromosome damage, are major occupational and health concerns. However, the biophysical mechanisms of chromosome instability subsequent to radiation-induced DNA damage are poorly understood. It is clear that interphase chromosomes occupy discrete structural and functional subnuclear domains, termed chromosome territories (CT), which may be organized into ‘neighborhoods’ comprising groups of specific CTs. We directly evaluated the relationship between chromosome positioning, neighborhood composition, and translocation partner choice in primary lymphocytes, using a cell-based system in which we could induce multiple, concentrated DNA breaks via high-dose irradiation. We critically evaluated mis-rejoining profiles and tested whether breaks occurring nearby were more likely to fuse than breaks occurring at a distance. We show that CT neighborhoods comprise heterologous chromosomes, within which inter-CT distances directly relate to translocation partner choice. These findings demonstrate that interphase chromosome arrangement is a principal factor in genomic instability outcomes in primary lymphocytes, providing a structural context for understanding the biological effects of radiation exposure, and the molecular etiology of tumor-specific translocation patterns.  相似文献   
82.
Polyketones with carbonyl groups in the polymer backbone (ethylene-carbon monoxide copolymer) have been converted into a novel polyoxime by means of C-nitrosation of the methylene groups and oximation of the carbonyl groups. The polyoxime is considered to be composed largely of 1,2-bis(hydroxyimino)trimethylene units. From the polyoxime and divalent Fe-, Co-, or Ni-salts, polymeric metal chelate complexes were prepared which are capable of combining reversibly with molecular oxygen and, especially the Fe-complex, also with carbon monoxide.  相似文献   
83.
This report describes an uncommon case of hypertrophic obstructive cardiomyopathy (HOCM) accompanying infundibular stenosis of the right ventricle treated by alcohol ablation therapy, in a 28-yr-old male patient presenting with dyspnea on exertion. HOCM with infundibular stenosis was detected by echocardiogram and cardiac catheterization and patient has dynamic obstructions of both ventricular outflow tracts. We performed alcohol ablation therapy to improve clinical symptoms and to relieve dynamic obstructions of both ventricular outflow tracts. This is the first case in which HOCM with infundibular stenosis of the right ventricle was treated by alcohol ablation therapy.  相似文献   
84.
Scrotal leiomyomas with atypical bizarre nuclei are rare, which might be misdiagnosed as malignant tumor. We describe a case of scrotal bizarre leiomyoma in a 65-yr-old man. The tumor was a 1 cm-sized, well circumscribed, oval mass arising from the tunica dartos muscle. Histologically, it was formed by whorling bundles of fusiform cells with occasional atypical, pleomorphic nuclei and pseudo-inclusions. Mitosis was not found. Although morphologically atypical, scrotal bizarre leiomyomas take on a biologic behavior not different from that of conventional leiomyoma, they should be distinguished from leiomyosarcoma to avoid unnecessary treatment.  相似文献   
85.
The herbal formulation "Jeo Dang-Tang" (JDT) has long been used for various cerebrovascular diseases. However, very little has scientific investigation been carried out. The aim of the present study is to investigate the effect of JDT on the production of various cytokines in the patients with cerebral infarction (CI). Peripheral blood mononuclear cells (PBMC) obtained from the patients with CI were cultured for 24h in the presence or absence of lipopolysaccharide (LPS) or phytohemagglutinin (PHA). The amount of interleukin (IL)-4, IL-10 and transforming growth factor (TGF)-1beta, in culture supernatant, was significantly increased in the JDT, LPS or PHA treated cells compared to unstimulated cells (P < 0.05). We also show that increased IL-4, and IL-10 level by LPS or PHA was significantly inhibited by JDT in a dose-dependent manner. Maximal inhibition rate of IL-4 and IL-10 production by JDT was 45 +/- 2% and 51 +/- 5% for LPS-stimulated cell and 41.5 +/- 3% and 70.8 +/- 2% for PHA-stimulated cells, respectively (P < 0.05). On the other hand, JDT significantly increased the LPS or PHA-induced TGF-beta1 production (P < 0.05). These data suggest that JDT has a regulatory effect on the cytokines production, which might explain its beneficial effect in the treatment of CI.  相似文献   
86.
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   
87.
综合ICU中低年资护士培训方法探讨   总被引:1,自引:0,他引:1  
目的探讨为综合ICU培养合格的护理人员的方法。方法根据ICU护士应具备的素质及低年资护士的特点,采用定期集中培训、一对一带教、参加护理查房等方法,对基础理论和基本技能进行强化,重点加强了ICU专科护理知识地训练。结果通过客观考核和主观考核,效果良好。结论经过为期12个月两个时段较规范的岗位培训,低年资护士能较好的适应ICU工作。  相似文献   
88.
Effect of aging on neuroglobin expression in rodent brain   总被引:5,自引:0,他引:5  
Neuroglobin (Ngb), a recently discovered O2-binding heme protein related to hemoglobin and myoglobin, protects neurons from hypoxic-ischemic injury in vitro and in vivo. In immunostained mouse brain sections, we found widespread expression of Ngb protein in neurons, but not astrocytes, of several brain regions that are prominently involved in age-related neurodegenerative disorders. Western blots from young adult (3 month), middle-aged (12 month), and aged (24 month) rats showed an age-related decline in Ngb expression in cerebral neocortex, hippocampus, caudate-putamen, and cerebellum. Loss of this neuroprotective protein may have a role in increasing susceptibility to age-related neurological disorders.  相似文献   
89.
The pathophysiology of meconium aspiration syndrome(MAS) is related to mechanical obstruction of the airways and to chemical pneumonitis. Meconium is also suggested to cause functional deterioration of pulmonary surfactant. Recent studies have reported that meconium inhibits the physical surface properties of pulmonary surfactant, and that administration of exogenous surfactant may provide therapeutic benefits in animal models or infants with respiratory distress due to MAS. To assess the effects of meconium on physical surface properties, especially the changes on the air-liquid interface and hypophase of pulmonary surfactant in vitro, we studied the following findings; a) the surface spreading rate(SSR) and the surface adsorption rate(SAR), b) the viscosity, c) the electron microscopic changes, on a series of mixtures with various concentrations of lyophilized human meconium and Surfactant-TA(SurfactenTM). The human meconium has significantly increased the surface tension of SSR and the viscosity of pulmonary surfactant, but had decreased the surface pressure of SAR of surfactant, and changed the electron microscopic findings of surfactant. We have concluded that these findings support the concept that meconium-induced surfactant dysfunction may play a role in the pathophysiology of MAS.  相似文献   
90.
The pre-transplantation goal of the urologist is the optimization of urinary tract condition. Therefore, urologic surgery may be needed before or after renal transplantation. We analyzed the results of urologic surgery performed because of de novo urologic diseases. Between January 1986 and January 2001, 281 patients underwent renal transplantation, and 23 urologic surgical procedures were performed on 21 transplant recipients before or after renal transplantation because of de novo urologic diseases. By review the major reasons for urologic surgery in recipients were polycystic kidney diseases, vesicoureteral reflux, and dysfunctional voiding disorders. Nineteen surgical corrective procedures were done average 2.9 months before transplantation. The mortality rate was 10.5%. Four patients underwent urologic surgery at an average 57.5 months after transplantation. We highlight the fact that patients with uremia are vulnerable to surgical complications, and conclude that more intensive longterm urologic follow-ups should be conducted on recipients.  相似文献   
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