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41.
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Background The timing of aggressive airway intervention in adult epiglottitis is controversial. Aims To correlate Friedman’s staging of epiglottitis on admission with the airway interventions undertaken. Methods A retrospective study of 23 adult patients, mean age 51 years (range 29–81 years), who had been admitted with acute supraglottitis between March 1988 and December 2000 was undertaken. Results Three patients (13%) had airway interventions; two with tracheostomy and one with tracheal intubation. All were Friedman stage III and had rapid symptom progression during the 24 hours prior to admission. Three other stage III patients with symptom progression longer than 24 hours and all the remaining patients (stage II or less) were managed with observation and intravenous therapy. Conclusions Friedman originally advocated airway intervention in any patient stage II or worse, but this intubation threshold should probably be lowered to those patients with rapid-onset stage III (moderate respiratory distress, stridor, respiratory rate >30 per minute, pCO2 >45mmHg) disease.  相似文献   
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I R Pickford  J L Craven  R Hall  G Thomas  W D Stone 《Gut》1984,25(4):393-397
In York between 1941 and 1949, 632 patients underwent Polya partial gastrectomy for peptic ulcer. Of 307 patients who were followed up in the York Gastric Clinic from 1971 to 1980, nine died of gastric cancer, three times the expected number. If gastrectomy was performed for gastric ulcer the risk of later development of carcinoma (7%) was significantly greater than that following operation for duodenal ulcer (1.6%) (p less than 0.001). No cancers were diagnosed in the 54 patients endoscoped. Atrophic gastritis was found in 98% of patients and intestinal metaplasia in 44%. Dysplasia was present in 35% but in no case was it severe. Although we have found that there is an increased risk of cancer developing in the gastric remnant we do not consider routine endoscopic follow up of all postgastrectomy patients to be a practical proposition.  相似文献   
45.
The hematopoietic stem cells of alpha-thalassemic mice   总被引:1,自引:0,他引:1  
Barker  JE; McFarland  E 《Blood》1985,66(3):595-601
The alpha-thalassemic mouse has a hereditary microcytic anemia, almost certainly has a shortened RBC life span, and is a potential candidate for cell replacement therapy. In a routine study of bone marrow repopulating capacity using hemoglobin as a cell marker, normal donor marrow cells, but not alpha-thalassemic donor marrow cells, completely replaced the host cells. Further analysis showed that at least 30 times more alpha-thalassemic cells were required to outcompete normal donor cells injected simultaneously. The results were more extreme then expected and suggested a defect in a stem cell population as well as in the RBCs. Evidence that the multipotent and erythroid-committed stem cells in alpha-thalassemic mice are not decreased was shown by CFU-S and CFU-E assays. The combined results indicate that the deletion expresses itself most conspicuously in the RBC population. Tests were also performed to analyze repopulation kinetics in the Hbath-J/+ mice. In unirradiated alpha-thalassemic hosts, the hemoglobin from a normal donor persisted but did not replace the host hemoglobin. Sublethally irradiated alpha-thalassemic hosts, on the other hand, were easily repopulated with normal cells. We conclude that the alpha-thalassemic mouse is a good model for cell replacement therapy.  相似文献   
46.
The aim of this study is to examine relationships of sleep duration with sociodemographic and health‐related factors, psychiatric disorders and sleep disturbances in a nationwide sample in Korea. A total of 6510 subjects aged 18–64 years participated in this study. Logistic regression was used to calculate the odd ratios and 95% confidence intervals of the covariates, psychiatric disorders and sleep disturbances across the following sleep duration categories: 5 h or less, 6, 7, 8 and 9 h or more per day. Low levels of education, unemployment and physical illness were associated with sleeping for 5 h or less and 9 h or more. Being older and widowed/divorced/separated, high levels of physical activity, pain/discomfort, obesity and high scores on the General Health Questionnaires were associated with sleeping for 5 h or less. Female, being younger and underweight were associated with sleeping for 9 h or more. Alcohol dependence, anxiety disorder and social phobia were associated significantly with sleeping for 5 h or less and 9 h or more. Other psychiatric disorders were more common in subjects who slept for 5 h or less (e.g. alcohol use disorder, mood disorder, major depressive disorder, dysthymic disorder, obsessive‐compulsive disorder and specific phobia) or 9 h or more (e.g. post‐traumatic stress disorder). In addition, subjects who slept for 5 h or less reported more sleep disturbances than did subjects who slept for 7 h. Short or long sleep is associated with psychiatric disorders and/or sleep disturbance, therefore attention to the mental health of short or long sleepers is needed.  相似文献   
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Clostridium perfringens strains (type A) isolated from an integrated poultry operation were subtyped using repetitive-element PCR with Dt primers. Isolates were obtained from fecal, egg shell, fluff, and carcass rinse samples as part of a previously reported temporally linked epidemiological survey. A total of 48 isolates of C. perfringens were obtained from different stages of the broiler chicken production chain from two separate breeder farms that supplied a single hatchery that in turn provided chicks to a single grow-out farm whose flocks were processed at a single plant. All 48 isolates were typeable (100% typeability) by repetitive-element PCR with Dt primers. This subtyping method was highly reproducible and discriminatory. By repetitive-element PCR with Dt primers, isolates were classified into four major branches with 12 subgroups or clades. The Simpson's index of discrimination was calculated to be 0.96 for groupings of >95% correlation. Toxin gene profiles of the isolates indicated that all of the isolates were C. perfringens alpha-toxin gene positive and 46 of 48 isolates were beta2-toxin gene positive. All strains were negative for beta- and epsilon-toxin genes. Repetitive sequence-based PCR was found to be a technically practical and reproducible means of subtyping C. perfringens libraries from specific epidemiological or production environment settings.  相似文献   
49.
Height is a highly heritable and classic polygenic trait. Recent genome-wide association studies (GWAS) have revealed that at least 180 genetic variants influence adult height. However, these variants explain only about 10% of the phenotypic variation in height. Genetic analysis of short individuals can lead to the discovery of novel rare gene defects with a large effect on growth. In an effort to identify novel genes associated with short stature, genome-wide analysis for copy number variants (CNVs), using single-nucleotide polymorphism arrays, in 162 patients (149 families) with short stature was performed. Segregation analysis was performed if possible, and genes in CNVs were compared with information from GWAS, gene expression in rodents'' growth plates and published information. CNVs were detected in 40 families. In six families, a known cause of short stature was found (SHOX deletion or duplication, IGF1R deletion), in two combined with a de novo potentially pathogenic CNV. Thirty-three families had one or more potentially pathogenic CNVs (n=40). In 24 of these families, segregation analysis could be performed, identifying three de novo CNVs and nine CNVs segregating with short stature. Four were located near loci associated with height in GWAS (ADAMTS17, TULP4, PRKG2/BMP3 and PAPPA). Besides six CNVs known to be causative for short stature, 40 CNVs with possible pathogenicity were identified. Segregation studies and bioinformatics analysis suggested various potential candidate genes.  相似文献   
50.
Maternal Smoking,Intrauterine Growth Restriction,and Placental Apoptosis   总被引:2,自引:0,他引:2  
Pregnant women who smoke are at greater risk of delivering a growth-restricted infant than nonsmoking mothers. We wanted to see if apoptosis could be involved in the mechanisms behind smoke-induced growth restriction, and our aim was to compare apoptosis in the placenta of smoking mothers giving birth to growth-restricted infants and nonsmoking mothers with infants of appropriate weight. The project was conducted at the Magee—Womens Hospital and Magee—Womens Research Institute, University of Pittsburgh, PA. Histological sections from 20 placentas were selected from smoking mothers who had given birth to small-for-gestational-age infants (birth weight 2 SD). The controls were gestational-age matched nonsmoking mothers with infants having appropriate-for-gestational-age weight. The TUNEL method was used to demonstrate DNA fragmentation in nuclei, and a monoclonal antibody M30, specific for a neo-epitope on cytokeratin 18, was used to identify apoptotic epithelial cells. The positive nuclei (TUNEL) and positive cells (M30-positive cytoplasm) were counted blindly both in villous tissue and in decidual/basal plate tissue. M30-positive cells in villous tissues were significantly increased in placentas from smoking mothers compared to nonsmoking mothers. When evaluated by the TUNEL method, the difference between the two groups of women was not significant. Our study shows that apoptosis was increased in the placentas of smoking mothers with growth-restricted infants. The difference between the two groups was mainly in the syncytiotrophoblast layer and in connection with perivillous fibrin deposition. Cigarette smoke with reduction in blood flow has previously been shown to increase apoptosis, and it is possible that this could be one of the mechanisms playing a role in the growth restriction.The work was performed at Magee—Womens Hospital and Magee—Womens Institute, University of Pittsburgh, Pittsburgh, PA, USA. 1; Deceased April 1, 2003, former address: Valley View Medical Center, 595 South 75 East, Cedar City, UT 84720, USA.  相似文献   
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