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981.
982.
983.
OBJECTIVE: An endoleak is defined as the presence of contrast medium within the aneurysm sac on post-operative contrast-enhanced computed tomography scans (CT) in patients following endovascular repair (EVR) of abdominal aortic aneurysms (AAA). The aim of this study was to correlate the incidence of endoleaks with the presence of patent lumbar (LA) and inferior mesenteric arteries (IMA) as seen on pre-operative angiography. DESIGN, MATERIALS AND METHODS: Forty-seven patients were assessed pre-operatively by both CT and angiography by a blinded radiologist prior to EVR of AAA. The number and size of patent vessels was recorded and correlated with the incidence of LA or IMA endoleaks on follow-up CT. Patent lumbar vessels were scored: 1 = small, 2 = medium, 3 = large. RESULTS: Five patients were noted to have patent IMA on pre-operative angiography but none developed an endoleak. In this series, five patients had an endoleak due to a patent LA. The median score for patients with no endoleak was 1 (0-9) and for those with a lumbar endoleak 2 (0-5) (P = 0.26, Mann-Whitney U-test). The number of patent lumbar arteries was not predictive of a subsequent endoleak. Two out of nine (22 %) patients with large patent LA subsequently developed an endoleak. If a policy of pre-operative embolization on the basis of large patent LA had been adopted, seven patients would have had an unnecessary invasive procedure. CONCLUSION: Pre-operative angiography to look for patent LA and IMAs is not required in patients undergoing EVR or AAA.  相似文献   
984.
The neuromuscular hamartoma (also referred to as the neuromuscular choristoma or benign triton tumor) is a rare developmental lesion composed of mature elements of both striated muscle and nerve. To date, less than 20 cases have been reported in the English language literature. The majority of these have involved large nerves, such as the sciatic or brachial plexus, but cutaneous lesions have also been reported. We report 2 cases that involve the head and neck and that are among the few described in this location. The majority of cases have been described in infants and young children. However, 1 of our cases (and at least 1 previously reported case) occurred in an adult. While surgical excision has been the most widely used form of therapy, a few cases have been complicated by and/or associated with a second lesion, such as a fibromatosis or lymphangioma.  相似文献   
985.
Three methods have been used to assess the conformational effects associated with ligand binding to two unrelated cyclic nucleotide receptor proteins: the cGMP-binding, cGMP-specific phosphodiesterase (cGB-PDE or PDE5A) and the cGMP-dependent protein kinase (PKG). The methods should be applicable to other proteins and to other types of modification such as phosphorylation. The procedures use either ion-exchange chromatography, size-exclusion chromatography, or native gel electrophoresis of these proteins in the absence and presence of regulatory ligands. Measurements from these respective approaches allow documentation of changes in the quaternary structure, surface electronegativity, and relative compactness (Stokes radius) of the protein molecule. The combined data allow the changes in protein conformation to be quantitated in terms of alterations in the axial ratio or length/width dimension of the molecule. The methods can be applied to partially purified proteins and to proteins that are available in limited quantities. Conformational changes due to stable modifications of proteins can be potentially examined in crude extracts of intact cells. Each of the methods can be tailored to optimize resolution of a particular protein under a variety of conditions. Activity measurements, Coomassie brilliant blue or silver staining of gels, radioautography, or Western blot analysis can be used for detection of the protein.  相似文献   
986.
This is a report on a questionnaire in Germany reflecting the activity in antireflux surgery, both in open and laparoscopic modifications in the time period of 1990 through 1995. It serves as an overview of the acceptance of diagnostic workup, indication, applied techniques, and different antireflux procedures. In a total of 104 representative hospitals, 2,036 patients were operated during this time. Almost 80% of the hospitals provide antireflux surgery in the open technique and only 1/3 of the hospitals have experience in the laparoscopic technique. There is a total rise in antireflux surgery during the last 5 years, since the number of laparoscopic antireflux operations rises constantly with a total amount of open operations of about 250 cases per year. In open surgery the most favourite technique is the Nissen-Rossetti procedure, while in laparoscopic technique the choice for the original Nissen, the Nissen-Rossetti, or the floppy Nissen technique is divided in almost equal parts.  相似文献   
987.
988.
Several cDNAs isolated from brains of diapausing pupae of the flesh fly, Sarcophaga crassipalpis, show expression patterns unique to diapause. To isolate such cDNAs a diapause pupal brain cDNA library was screened by using an elimination hybridization technique, and cDNAs that did not hybridize with cDNA probes constructed from the RNA of nondiapausing pupae were selected for further screening. The 95 clones that did not hybridize in the initial library screen were selected for further characterization. These clones were then screened against diapause and nondiapause pupal poly(A)+ Northern blots. The secondary screen identified 4 diapause-up-regulated clones, 7 diapause-down-regulated clones, 8 clones expressed equally in both diapause and nondiapause, and 75 clones without detectable expression. The diapause-up-regulated and down-regulated clones were further characterized by partial DNA sequencing and identity searches by using GenBank. Identities between our cloned cDNAs and other genes included those linked to cell cycle progression, stress responses, and DNA repair processes. The results suggest that insect diapause is not merely a shutdown of gene expression but is a unique, developmental pathway characterized by the expression of a novel set of genes.  相似文献   
989.
Insulin-dependent diabetes mellitus (IDDM) and Graves' disease (GD) are autoimmune endocrinopathies and associated with distinct HLA-DR and -DQ alleles as well as several tumor necrosis factor alpha (TNF-alpha) and beta (TNF-beta) alleles. TNF-alpha and TNF-beta interact with TNF receptor (TNF-R), of which two subtypes have been described: TNF-R1 and TNF-R2. We investigated TNF-R2 alleles in 90 patients with IDDM, 101 with GD and 70 healthy controls. Genomic DNA was amplified with specific flanking primers for the untranslated 3' region of TNF-R2. SSCP analysis revealed two alleles by different fragment patterns: TNF-R2*1 and TNF-R2*2. Patients with IDDM or Graves' disease and controls did not differ significantly: TNF-R2*1/*1:IDDM(8%)/GD(2%)/KO(4%); TNF-R2*2/*2:IDDM(34%)/GD(48%)/KO(42%), heterozygosity TNF-R2*1/*2:IDDM(58%)/GD(50%)/KO(54%) (IDDM vs KO: P=0.46, chi2=1.57; GD vs KO: P=0.59, chi2=1.05). In conclusion, the studied polymorphism of TNF-R2 was associated with neither IDDM nor GD in a German population.  相似文献   
990.
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