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21.
We report the clinical and pathologic findings of two patients with sporadic visceral myopathy. Both presented with chronic intestinal pseudo-obstruction that necessitated colectomy. Microscopically, typical changes of primary visceral myopathy were present, including variable fibrous replacement of the muscularis externa and vacuolar degeneration of myocytes. In addition, the muscle cells contained cytoplasmic inclusions that have only been recently reported in visceral myopathy. These inclusions were numerous and easily visible in routine hematoxylin-eosin-stained sections but greatly enhanced by periodic acid-Schiff staining. They were reactive immunohistochemically at their periphery and were seen to be myofibrils at various stages of degeneration on electron microscopy. Inclusions were present in both muscularis externae and muscularis mucosae and were identified in mucosal biopsy specimens, providing a means of diagnosing this type of myopathic change on endoscopic biopsies.  相似文献   
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African trypanosomes compartmentalize glycolysis in a microbody, the glycosome. When growing in the mammalian bloodstream, trypanosomes contain only a rudimentary mitochondrion, and the first seven glycolytic enzymes, including phosphoglycerate kinase, are located in the glycosome. Procyclic trypanosomes, growing in the gut of tsetse flies, possess a fully developed mitochondrion that is active in oxidative phosphorylation. The first six glycolytic enzymes are still glycosomal, but phosphoglycerate kinase is now found in the cytosol. We demonstrate here that bloodstream trypanosomes are killed by expression of cytosolic phosphoglycerate kinase. The toxicity depends on both enzyme activity and cytosolic location. One possible explanation is that cytosolic phosphoglycerate kinase creates an ATP-generating shunt in the cytosol, thus preventing full ATP regeneration in the glycosome and ultimately inhibiting the first, ATP-consuming, steps of glycolysis.  相似文献   
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Tooth loss diminishes oral function and quality of life, and national health targets aim to reduce population levels of tooth loss. OBJECTIVES: The purpose of this study was to determine tooth loss incidence and predictors of tooth loss among older adults in South Australia. METHODS: Data were obtained from a cohort study of a stratified random sample of community-dwelling dentate people aged 60+ years. Interviews and oral examinations were conducted among 911 individuals at baseline and among 693 of them (76.1%) 2 years later. Incidence rates and relative risks were calculated for population subgroups and multivariate logistic regression was used to construct risk prediction models. A method was developed to calculate 95% confidence intervals (95% CI) for relative risks (RR) from logistic regression models using a Taylor series approximation. RESULTS: Some 19.5% (95% CI = 15.4-23.6%) of people lost one or more teeth during the 2 years. Men, people with a recent extraction, people who brushed their teeth infrequently, smokers and people born outside Australia had significantly (P < 0.05) greater risk of tooth loss. Baseline clinical predictors of tooth loss included more missing teeth, retained roots, decayed root surfaces, periodontal pockets and periodontal recession. In a multivariate model that controlled for baseline clinical predictors, former smokers (RR = 2.55, 95% CI = 1.48-4.40) and current smokers (RR = 2.06, 95% CI = 0.92-4.62) had similarly elevated risks of tooth loss compared with non-smokers. CONCLUSIONS: The findings from this population suggest that a history of smoking contributes to tooth loss through mechanisms in addition to clinical disease processes alone.  相似文献   
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We have screened 57 cases of primary, nonfunctional, pituitary adenomas for loss of heterozygosity of markers on chromosome 9p. Using a panel of 11 microsatellite markers, we found hemizygous deletion with at least one of the markers in 18 tumors (31.5%). The frequency of loss was similar in both noninvasive (8 of 26; 31%) and invasive tumors (10 of 31; 32%), suggesting that loss on this chromosome might be an early event in pituitary tumorigenesis. Two discrete areas of loss were punctuated by a region of retention of heterozygosity between the markers D9S171 and IFNA, indicative of homozygous deletion. However, multiplex PCR analysis (MTS1 and MTS2) and the presence of a 3' untranslated region polymorphism in MTS1 suggested that neither of these tumor suppressor genes was homozygously deleted. In 6 of the 18 tumors showing LOH, sufficient DNA was also available for Southern blot analysis and, in all cases, showed retention of MTS1. Cell mixing experiments of tumor cell DNA homozygously deleted for MTS1 with DNA in which neither copy of the gene was deleted only gave rise to a signal at contamination levels greater than 30% and could discriminate homozygous and hemizygous loss. These studies support the recent findings that mechanisms other than hemi- and homozygous deletion are most likely responsible for the loss of MTS1 gene product in pituitary tumors (M. Woloschak et al., Cancer Res., 56: 2493-2486, 1996.). These data show that losses on either side of 9p21-22, both or either of which may be deleted, are involved in pituitary tumorigenesis and provide evidence for distinct suppressor gene loci, in addition to MTS1, on chromosome 9p.  相似文献   
26.
A test method useful in determining the effects of polymer additives upon water carry-over (WCO) in water quenched, cast film extrusion is presented. Data from this test is obtained on film specimens based in a Spherilene process HDPE resin individually doped with 250 and 500 ppm of six various primary and secondary antioxidants and acid scavengers. Water contact angles and film surface tension data is also presented. The WCO test is reproducible and data may be applied to commercial production. Different additives that carry out the same function in the polymer may have greatly varying WCO properties; these differences are not detected by equilibrium goniometry.  相似文献   
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To select a source of lymphocytes for the generation of an anti-sperm-biased combinatorial phage display library, venous blood was obtained from 34 vasovasostomy (vasectomy reversal) patients approximately 3 mo after surgery. Using a variety of immunoassays, serum was analyzed for antibodies against human spermatozoa, and a patient was selected on the basis of high titer of antibodies that recognized the equatorial region of the sperm head and inhibited sperm fertilizing capacity in vitro. Total RNA isolated from the stored lymphocytes of this individual was reversed transcribed, and gamma1 (Fd) region and kappa chains were amplified by polymerase chain reaction for the successful construction of an antibody phage display library. The library was panned against human spermatozoa to isolate sperm-specific phage that recognized the equatorial region of the sperm head. Three preparations of Fab were tested via the hamster egg penetration test. Each preparation significantly (p < 0. 005) inhibited sperm-egg binding and fusion, with one preparation (designated Fab-G) causing complete inhibition. Sequence analysis of the kappa light gene encoding Fab-G revealed a 93% homology with the light chain of human anti-human immunodeficiency virus gp120 p35 variable region. This technology may have a practical application in characterization of the immune response to spermatozoa and for the design of sperm-based contraceptive vaccines.  相似文献   
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The Eysenck Personality Profiler (EPP), a set of 21 scales measuring primary traits hypothesized to be definers of Neuroticism, Extraversion, and Psychoticism factors, was administered to 229 adults together with the Eysenck Personality Questionnaire--Revised (H. J. Eysenck & S. B. G. Eysenck, 1991) and the Revised NEO Personality Inventory (NEO-PI-R; P. T. Costa & R. R. McCrae, 1992b). Correlations of EPP scales with NEO-PI-R facet scales provided preliminary evidence supporting the convergent and discriminant validity of the EPP scales. However, varimax and targeted validimax factor analyses suggested that some EPP scales were misclassified and that EPP scales could better be understood in terms of the 5-factor model than the intended 3-factor model.  相似文献   
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