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101.
102.
An association between chromosomal fragile sites and cancer-specific breakpoints has been found to be statistically significant. Cancer patients have been shown to be carriers of fragile sites in chromosome regions involved in rearrangements in malignant cells. Based on these observations it has been hypothesized that fragile sites may be involved in the pathogenesis of human tumors. We have recently described a new recurrent cancer breakpoint at chromosomal region 12q13-q14 in adipose tissue tumors. The possible involvement in these tumors of the rare folate-sensitive fragile site 12q13.1 has been investigated in PHA-stimulated peripheral blood cells from three patients carrying the t(12;16)(q13;p11) in their liposarcoma cells and one patient with the t(3;12)(q28;q14) in his lipoma cells. No expression of the fragile site 12q13.1 could be detected in the blood lymphocytes of any of the patients. The involvement of the fragile site 12q13.1 in the pathogenesis of adipose tissue tumors with a 12q13-q14 breakpoint remains to be established.  相似文献   
103.
There have been comparatively few scanning electron microscopic (SEM) studies of mucosal biopsies of the human upper gastrointestinal tract. This study reviews the use of SEM in human oesophageal research and deals with the results of a SEM study of thirty two biopsies of human oesophagus, taken from eighteen patients during endoscopy for upper gastrointestinal symptoms. For each biopsy, three areas of the mucosal surface chosen at random were examined using standard magnifications. The SEM showed three mucosal patterns, which were designated typical squamous, atypical squamous and nonsquamous, each displaying common features in relation to desquamation, cell boundaries and microridges. The two squamous epithelial groups showed surface microridges. The typical group displayed clear cut cell boundaries and well developed microridges arranged in rows. The atypical squamous group showed desquamation, less well developed cell boundaries and variation in microridge patterns. Many nonsquamous specimens displayed simple columnar epithelium, similar to mucosa of gastric type. Care was taken to correlate the surface structure of the oesophagus with the endoscopic appearance. The two assessments were done independently and the material was coded throughout. The broad subdivision of the biopsies into groups using these qualitative topographical criteria gave good correspondence with the endoscopic appearance.  相似文献   
104.
105.
The aim of this study was to evaluate the immunoexpression of HER-2 in gastric cells of cats infected with Non H. pylori Helicobacter (NHPH) and to investigate an association with the presence of inflammatory infiltrate. Forty-eight paraffin-embedded gastric samples were retrieved from the archives of the Veterinary Anatomic Pathology Laboratory that had previously been shown to be positive for NHPH with the rapid urease test and cytology. Infection by NHPH was confirmed by histopathology using the Warthin-Starry staining. Hematoxylin-eosin stained sections were reviewed to evaluate inflammatory cell infiltrates. Immunohistochemical analysis was done using anti- H. pylori antibody and anti-HER-2 antibody. Molecular analysis was performed by PCR to confirm the presence of Helicobacter. Statistical analysis was performed to determine whether there was an association between the presence of H. Heilmannii and HER-2 expression in gastric samples. All samples were positive for NHPH, by immunohistochemistry, and confirmed by PCR as H. Heilmannii. On histopathologic analysis, 56,3% of the samples had lymphocytes and plasma cells infiltrates, 52,1% of which were mild and 4,2% moderate. The intensity of the inflammatory infiltrate in the gastric mucosa was significantly greater in the complete plasma membrane of parietal cells of gastric glands that had greater HER-2 immunoexpression (p = 0.0001). A statistically significant association (p = 0.007) between the H. Heilmannii infection score and the expression of HER-2 in the lateral membrane of gastric surface cells was observed. HER-2 expression may be increased in feline gastric cells infected by H. Heilmannii and in parietal cells of gastric glands with an increased inflammatory infiltrate.  相似文献   
106.
European Journal of Applied Physiology - This study examined the time course of contralateral adaptations in maximal isometric strength (MVC), rate of force development (RFD), and rate of...  相似文献   
107.
Summary We have analyzed the expression and function of the intron-encoded bI4 maturase when frame-shift mutations in the upstream exon alter the translational process. By constructing secondary cis-acting mutations within the b14 intron, we observed (1) that the bI4 maturase is still translated in the presence of the upstream mutation, albeit in very low amounts, and (2) that the limited amounts of bI4 maturase made under these conditions is no longer able to promote the splicing process of the aI4 intron. These observations, which further strengthen the maturase model, strongly suggest that bI4 maturase acts sequentially on the bI4 intron and then on the aI4 intron.  相似文献   
108.
BACKGROUND: The incidence of cystic fibrosis (CF) in Asians is rare. How these patients fare in terms of morbidity and mortality in the UK compared to their non-Asian peers is not well documented. AIMS: To retrospectively study annual reviews of 31 Asian CF patients from three London paediatric CF centres. METHODS: Disease severity was assessed by lung function, age at first infection with Pseudomonas aeruginosa, and body mass index (BMI). The Asian children were compared with 143 matched non-Asian patients with CF. Matching criteria used were same sex and treatment centre as the Asian index patient. In addition, the controls were matched so that their date of birth, date of diagnosis, and date at annual review were within 12 months of the index patient. RESULTS: There was no significant difference in age at diagnosis or age at annual review between the Asian and non-Asian children. Mean Z-scores for FEV1 and FVC were significantly lower for the Asian girls. There was no significant difference in Z-scores for BMI between the Asian children and their controls. Age at first isolation of Pseudomonas aeruginosa in Asian girls was significantly later than for their controls (8.3 years compared to 5.6 years for non-Asian girls). CONCLUSIONS: While the Asian boys' lung function seems comparable with that of their non-Asian peers, the Asian girls emerge as a potentially vulnerable group and more work is required to discover why this is the case.  相似文献   
109.
Summary An electron microscopic study of cell cultures and bovine foetal tracheal organ cultures infected with infectious bovine rhinotracheitis (IBR) virus showed the following. a) The difference in the site at which the outer envelope is acquired in the infected cell is responsible for some morphological differences between the virions. Where envelopment of the capsids occurs by budding into cytoplasmic tubules, dense material adjacent to the tubules is often incorporated between the capsid and the outer envelope, giving a pleomorphic appearance to the latter. No dense material is seen in the same position if envelopment occurs in the nucleus. b) Dense material adjacent to the cytoplasmic tubules is not only incorporated in the virions, but may also bud into the cytoplasmic tubules without nucleocapsids, thus giving rise to dense bodies. c) Dense material in the virions is closely adjacent to the inner side of the outer envelope, but is separated from the capsid by a lucent zone. A similar zone can be seen around some nucleocapsids in the nucleus. d) The outer envelope of numerous extracellular virions and of those located in the cytoplasmic tubules shows the unit membrane structure with projections. The outer envelope of intranuclear particles and of those located in the perinuclear cisterna had the appearance of a dense membrane.With 11 Figures  相似文献   
110.
Nebulised colistin is regularly used as antipseudomonal therapy in children with cystic fibrosis. We assessed bronchoconstriction in response to nebulised colistin in 58 children. Nebulised colistin significantly reduced FEV(1), MEF(25%), and SaO(2) for 15 minutes. In 20 children the reduction was greater than 10% from baseline FEV(1), and was still at that level in five at 30 minutes. Subjective assessment, baseline FEV(1), and serum IgE were unable to identify susceptible children. It is recommended that children receiving colistin should be carefully assessed for bronchoconstriction.  相似文献   
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