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排序方式: 共有4496条查询结果,搜索用时 15 毫秒
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Sonographic evaluation of gallbladder kinetics: in vitro and in vivo comparison of different methods to assess gallbladder emptying. 总被引:3,自引:0,他引:3
Bernd Wedmann Gabriele Schmidt Martin Wegener Christoph Coenen Dieter Ricken Cornelia Drge 《Journal of clinical ultrasound : JCU》1991,19(6):341-349
In an in vitro study, 10 gallbladders of adult pigs and 6 gallbladders of lambs, all removed immediately after slaughtering, were stimulated in a water bath by electric means to induce active contraction. Gallbladder emptying was followed by ultrasonography employing five measurement procedures: (1) gallbladder width, (2) longitudinal planimetry, (3) transverse planimetry, (4) ellipsoid method, and (5) sum of cylinders method. In an in vivo investigation, gallbladder emptying of 30 volunteers (12 healthy subjects, 18 diabetics) was evaluated in the same way after ingestion of a fatty meal. Gallbladder width was found to be unsuitable to estimate the decrease in gallbladder volume due to a nonlinear relation of the parameters. Longitudinal planimetry tended to be less valid than transverse planimetry in assessing gallbladder volume reduction. The most valid estimation of gallbladder volume decreases was obtained by the two three-dimensional procedures. However, in neither in vitro nor in vivo could a significant difference between the sum of cylinders method and the ellipsoid method in determining relative volume reduction be established. We conclude that a three-dimensional measurement procedure should be used for valid assessments of gallbladder motility. However, according to our data there is no advantage in using the time-consuming sum of cylinders method compared to the simple ellipsoid method. 相似文献
5.
Jens J Bock Peter Maurer Cornelia Otto Robert A W Fuhrmann Johannes Schubert 《Journal of cranio-maxillo-facial surgery》2006,34(3):156-161
AIM: The aim of this study was to analyse possible intra- and postoperative complications and long-term results in combined orthodontic-orthognathic treatment of mentally handicapped patients compared with a control group of patients without handicap. PATIENTS AND METHODS: A group of 20 mentally handicapped patients (male = 7, female = 13) and of 102 non-handicapped patients (male = 36, female = 66) were evaluated retrospectively. The results of the two point-discrimination sensory test and the cephalometric findings of both groups were assessed. Complications during and after the operation, the results of nerve function tests and relapse rates were reported. The statistical analysis was carried out using binary logistical regression analysis with adjustment according to the diagnosis and the type of operation (p < 0.05) RESULTS: No significant differences could be found between the mentally handicapped and the non-handicapped patients. Only the nerve function test immediately postoperatively revealed differences between the two patient groups. The relapse rate in mentally handicapped patients was similar to non-handicapped patients. Forty-seven months after the operation, relapse (change in the ANB angle of more than 0.5 degrees ) was observed in four patients only (handicapped patients). CONCLUSION: Orthognathic surgical procedures in mentally handicapped patients can be carried out with a similarly high success rate as in mentally healthy patients. 相似文献
6.
Claudia Linde Cornelia Löffler Christina Kessler U. Quast 《Naunyn-Schmiedeberg's archives of pharmacology》1997,356(4):467-474
In vascular smooth muscle, openers of ATP-dependent potassium channels (K
ATP channels), such as P1075 (N-cyano-N’-(1,1-dimethylpropyl)-N’’-3-pyridylguanidine), produce relaxation. In this study we have investigated the effects of thiol-modifying agents on the
binding of P1075 and on the 86Rb+ efflux stimulating and vasorelaxant effects of the opener in rat aortic rings. The increase in 86Rb+ efflux induced by P1075 was taken as a qualitative measure of K+ channel opening. The hydrophilic SH-group-oxidizing substance, thimerosal (1 to 100μM), abolished specific binding of [3H]-P1075 with an IC50 value of 7.6±1.2μM; at 30μM, the half time for inhibition was 38min. Two other thiol-oxidizing agents, PMB (4-hydroxy-mercuribenzoic
acid) and DTBNP (2,2’-dithio-bis(5-nitropyridine)), inhibited binding up to 86% and 44%, respectively. The disulphide bond
reducing substance, DTT (1,4-dithiothreitol, 0.1 to 1mM), reduced [3H]-P1075 binding by up to 20% and partially reversed the inhibitory effect of thimerosal. In 86Rb+ efflux experiments, thimerosal (3 to 100μM) concentration-dependently increased basal efflux but inhibited P1075-stimulated
tracer efflux with an IC50 value of 7±1μM. The inhibitory effect occurred with a half-time of approximately 8min and was essentially reversed by DTT.
In rings precontracted with noradrenaline, thimerosal inhibited the vasorelaxant effect in a noncompetitive manner, shifting
the concentration-relaxation curves to the right and reducing maximum relaxation.The data show that oxidation of thiol groups
interferes with the binding of the K
ATP channel opener, P1075; concomitantly, the 86Rb+ efflux stimulating and the vasorelaxant effects are inhibited. Reduction of disulphide bonds by DTT has only minor effects
on the action of P1075. Collectively, the results suggest that intact thiol groups are essential for the functioning of the
KATP channel in rat aorta. The different kinetics governing the inhibition of opener binding and of opener-stimulated 86Rb+ efflux suggest that the SH-groups involved in the two processes differ in their accessibility to thimerosal and/or in their
reactivity.
Received: 7 April / Accepted: 9 July 1997 相似文献
7.
Cornelia Bormann 《Sozial- und Pr?ventivmedizin》1994,39(2):67-74
Zusammenfassung Mit Hilfe der Daten aus dem Nationalen Gesundheitssurvey wird die Frage diskutiert, inwieweit Angaben zu Krankheiten in einer Befragung zur Abschätzung von Prävalenzen für eine Gesundheitsberichterstattung herangezogen werden können. An dem Beispiel der Selbstangaben zum Herzinfarkt wird die Reliabilität und Plausibilität solcher Daten untersucht. Abschliessend werden diese Zahlen Daten aus anderen Quellen, wie dem Herzinfarkt-Register und Fragebogenerhebungen, gegenübergestellt, um beurteilen zu können, ob die Raten plausibel sind Da jedoch auch die anderen Datenquellen ihre Schwächen und Defizite haben, wird der Nutzen von krankheitsbezogenen Selbsteinschätzungen zum Herzinfarkt insgesamt als positiv bewertet, weil damit auch Beziehungen zu sozialen und verhaltensbezogenen Merkmalen untersucht werden können.
Summary With the data of the German National Health Survey the question is discussed, if self-reports on diseases, gained in a survey, are useful for estimating prevalences within the German population. Self-reports on myocardial infarction serve as an example for examining the reliability and plausibility of such data. The prevalence rate for myocardial infarction in this survey is compared with prevalence rates of other data sources as the MONICA-register and surveys. Because these other data sources have some problems and deficits according to their validity too, the value of self-reports on diseases from the National Health Survey is seen positively for establishing a health reporting system.
Résumé Les données de l'Enquête Nationale de la Santé en RFA sont discutées. La question est de savoir siles données subjectives de l'infarctus du myocarde peuvent être utilisées pour estimer des prévalences dans la population allemande. Dans cette étude les problèmes de compatibilité des données d'un questionnaire sont examinées et comparées avec des études similaires. Carles relevés du registre de l'infarctus du myocarde et d'autres enquêtes ont aussi des problèmes de validité, les données subjectives de l'Enquête Nationale sont jugées positivement pour estimer des prévalences de l'infarctus du myocarde. Avecces données il est posible en outre, d'analyser des prévalences se référant aux indicateurs sociaux et concernant une ligne de conduite pour la santé.相似文献
8.
Henriëtte A. van Steensel-Moll Cornelia M. van Duijn Hans A. Valkenburg George E. van Zanen 《Cancer causes & control : CCC》1992,3(4):389-390
Dutch Childhood Leukemia Study Group, Erasmus University Medical School 相似文献
9.
Gysèle S Bleumink Anna F C Schut Miriam C J M Sturkenboom Jaap W Deckers Cornelia M van Duijn Bruno H Ch Stricker 《Genetics in medicine》2004,6(6):465-474
Heart failure is a complex clinical syndrome. There is evidence for a genetic contribution to the pathophysiology of heart failure. Considering the fundamental role of neurohormonal factors in the pathophysiology and progression of cardiac dysfunction and hypertrophy, variants of genes involved in this system are logical candidate genes in heart failure. In this report, genetic polymorphisms of the major neurohormonal systems in heart failure will be discussed. Studies on polymorphisms of the renin-angiotensin-aldosterone system (RAAS), adrenergic receptor polymorphisms, endothelin (receptor) polymorphisms, and a group of miscellaneous polymorphisms that may be involved in the development or phenotypic expression of heart failure will be reviewed. Research on left ventricular hypertrophy is also included. The majority of genetic association studies focused on the ACE I/D polymorphism. Initial genetic associations have often been difficult to replicate, mainly due to problems in study design and lack of power. Promising results have been obtained with genetic polymorphisms of the RAAS and sympathetic system. Considering the evidence so far, a modifying role for these polymorphisms seems more likely than a role of these variants as susceptibility genes. Besides the need for larger studies to examine the effects of single nucleotide polymorphisms and haplotypes, future studies also need to focus on the complexity of these systems and study gene-gene interactions and gene-environment interactions. 相似文献
10.
Mobilization and evolutionary history of miniature inverted-repeat transposable elements (MITEs) in Beta vulgaris L. 总被引:1,自引:0,他引:1
Gerhard Menzel Daryna Dechyeva Heiko Keller Cornelia Lange Heinz Himmelbauer Thomas Schmidt 《Chromosome research》2006,14(8):831-844
We have identified three families of miniature inverted-repeat transposable elements (VulMITEs) in the genome of sugar beet
(Beta vulgaris L.), evidently derived from a member of the Vulmar family of mariner transposons. While VulMITEs I are typical stowaway-like MITEs, VulMITEs II and VulMITEs III are rearranged stowaway elements of increased size. The integration of divergent moderately and highly repetitive sequences into VulMITEs II and,
in particular in VulMITEs III, respectively, shows that amplification of repetitive DNA by MITEs contribute to the increase
of genome size with possible implications for plant genome evolution. Fluorescent in-situ hybridization (FISH), for the first time visualizing stowaway MITE distribution on plant chromosomes, revealed a dispersed localization of VulMITEs along all B. vulgaris chromosomes. Analysis of the flanking sequences identified a dispersed repeat as target site for the integration of the stowaway element VulMITE I. Recent transposition of VulMITE I, which most likely occurred during the domestication of cultivated beets, was concluded from insertional polymorphisms between
different B. vulgaris cultivars and species.
†Sequence data from this article have been deposited in the EMBL/GenBank Data Library under the accession nos. AM231630-AM231653
and AM259123-AM259125. 相似文献