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31.
Peptides may function as neurotransmitters liberated antidromically by sensory nerve fibres, provoking vascular responses having potential importance in some neurological disorders. Dose-response relaxation curves induced by substance P (SP) and calcitonin gene related peptide (CGRP) have been studied in porcine ophthalmic arteries in vitro. Both peptides induced vasodilation when tested separately (CGRP much greater than SP). Because of the putative interactions between such peptides in this vascular territory, a computerised system was also used for analysing over time the response to a single addition of either 10(-8) M CGRP, 10(-8) M SP or a combination of 10(-8) M SP + 10(-8) M CGRP. SP did not augment the maximum relaxation induced by CGRP alone, but increased significantly the rate of relaxation during the initial phase of the response. The effect induced by the SP+CGRP combination was stronger than the sum of the individual SP and CGRP-induced relaxations during the first 4 min of the response, which suggests a SP-CGRP synergism in this artery.  相似文献   
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Our group has previously reported significant changes in the incorporation of precursors into glycerophospholipids, particularly phosphatidylserine, in polymorphonuclear cells obtained from the peripheral blood of cluster headache patients, when compared with controls. The potential of these results led to further work using both the previous methodology and a modified isolation technique to obtain polymorphonuclear cells in as pure a state as possible. Neither the new results obtained using the original technique, nor the results with high purity polymorphonuclear cells from controls and cluster headache patients, confirm the marked changes in precursor uptake into glycerophospholipids originally reported.  相似文献   
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Résumé Parallèlement à l'enregistrement systématique des cas d'infarctus, le projet MONICA prévoit de mesurer à trois reprises le niveau des facteurs de risque cardio-vasculaires auprès d'un échantillon aléatoire. L'article présente le plan d'échantillonnage de ce premier «examen de santé» MONICA réalisé dans les cantons de Vaud, de Fribourg et du Tessin. Il s'agit d'un plan à deux niveaux, avec tirage stratifié des communes en fonction de leur taille, puis tirage des individus dans les fichiers communaux. Les conditions d'un plan d'échantillonnage efficace dans le cadre plus général de l'inférence statistique sont abordées dans une première partie théorique. Les raisons pratiques (contraintes budgétaires, problèmes de logistique, disponibilité des fichiers administratifs) qui ont motivé le choix de ce plan sont exposées ensuite. Une troisième partie décrit toutes les étapes de sa réalisation, avec les difficultés méthodologiques et concrètes rencontrées. La discussion porte sur une évaluation critique de toute la procédure qui, dans le cadre du projet MONICA, a produit des échantillons dont le degré d'adéquation avec la population est assez élevé.
Theoretical and practical aspects of sampling: the MONICA-Project.
Summary In parallel with the systematic registration of myocardial infarction, the MONICA-Project attempts to investigate at three different times the prevalence of risk factors for cardiovascular disease in the population. This article presents the sampling plan of the first MONICA survey in the cantons of Vaud, Fribourg and Tessin. The sampling procedure was at two levels: first, a sample of communes stratified according to community size was chosen, and secondly, within these communities, individuals were selected from the population registries. The prerequisites for an efficient sampling plan are discussed on a theoretical level. In addition, the practical constraints (budget, organizational problems, population registry files) are presented. Finally, all steps of the sampling procedure are described including the difficulties encountered. The discussion attempts a critical evaluation of the whole MONICA sampling procedure whose results are largely satisfactory.

Theorie und Praxis der Stichprobenbildung: das Beispiel des MONICA-Projektes
Zusammenfassung Neben einer systematischen Erfassung der Infarktfälle sieht das MONICA-Projekt eine dreimalige Erfassung der Risikofaktorenprävalenz vermittels einer Zufallsauswahl vor. Der vorliegende Artikel schildert den Stichprobenplan der ersten in den Kantonen Waadt, Freiburg und Tessin durchgeführten Untersuchung. Es handelt sich um einen zweistufigen Stichprobenplan: zuerst wurde eine Ziehung der Gemeinden — stratifiziert nach Gemeindegrösse — vorgenommen, danach wurden die Individuen auf Grund der Einwohnerregister gezogen. Die Grundbedingungen für einen effizienten Stichprobenplan werden in einem ersten theoretischen Abschnitt diskutiert. Im weiteren werden die konkreten Bedingungen der MONICA-Stichprobenziehung dargestellt (Budget-Limiten, organisatorische Probleme, Aufbau der Einwohnerregister). Ein dritter Teil beschreibt sämtliche Schritte der eigentlichen Stichprobenbildung einschliesslich der aufgetretenen Schwierigkeiten. Die Diskussion nimmt eine Gesamtbeurteilung der Stichprobenziehung im MONICA-Projekt vor, deren Ergebnis recht befriedigend ausfällt.
  相似文献   
34.
For the past decade, US physicians have failed to embrace disease management (DM) approaches offered by private DM companies and health plans. Until recently, physicians have not offered an alternative, systematic approach to caring for patients with chronic illnesses and conditions.The medical home model has become the centerpiece of reforms proposed by associations that represent family medicine physicians (the American Academy of Family Physicians [AAFP]) and general internal medicine physicians (the American College of Physicians [ACP]). In February 2007, the AAFP and the ACP were joined by the American Academy of Pediatrics and the American Osteopathic Association in issuing joint principles for the patient-centered medical home. While the medical home model is promoted primarily as a comprehensive approach to primary care reform, there is one aspect where the medical home and DM overlap: care coordination.Medicare has been exploring alternative mechanisms to manage and reimburse chronic care and care-coordination activities. In 2003, the US Congress passed legislation to require pilot projects for chronic care improvement programs; the program implementing this legislation is Medicare Health Support (MHS). To date, very little information has been available about the progress of MHS projects. The three early announcements about MHS progress have not been encouraging: the expected financial results are not being achieved.In December 2006, Congress passed legislation authorizing the Medicare Medical Home Demonstration (MMHD) project. MHS and MMHD are directed at similar patient populations: high-cost, frail, elderly patients with multiple co-morbid conditions. The medical home concept being advanced by primary care physicians has the potential to be competitive with DM companies. Health plans that have built their own DM programs are more likely to be supportive of the medical home model. Do physicians have the ability to compete at providing care-coordination services? There are strong arguments suggesting ‘no’ and strong arguments suggesting ‘yes’.While the medical home model is focused on primary care reform, its effect could be competitive to DM companies and others. The medical home model could affect the flow of hundreds of billions of dollars — money that over time might flow either to physicians or to private companies.  相似文献   
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SUMMARY Disease-modifying antirheumatic drugs are used in virtually all patients with established rheumatoid arthritis. An increasingly large number of new drugs is now available. Furthermore, old therapies are being used in novel ways. Treatment is now begun earlier and patients are rarely left untreated. This report summarises recent developments regarding the drugs currently in use and those that may be available in the near future.  相似文献   
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Success of meniscal repair with early or immediate motion depends on the ability of the suture fixation to withstand the loads applied. Vertical and horizontal mattress suture techniques were tested using 2-0 Ethibond, and 0-PDS and 1-PDS sutures (Ethicon, Somerville, NJ). Mulberry knot technique was tested with 0-PDS and 1-PDS sutures. Twenty menisci (60 sutures) were tested for each suture material. Sutures were placed 3 to 4 mm from the peripheral edge of the meniscus with double barreled cannulas for vertical and horizontal mattress techniques or a spinal needle for the mulberry knot technique, reproducing clinical techniques of meniscal repair. Mechanical testing of suture fixation was performed to failure at a rate of 10 mm/min on a MTS material testing system (MTS Systems Corp. Minneapolis, MN). Suture pullouts were reported as the load displacement to failure from the inner fragment only, because clinical failure would ensue should a suture pull through the inner fragment of a tear. Vertical mattress technique with 1-PDS suture had significantly greater load to failure than any other combination (P < .05). Analysis of variance showed that the vertical mattress technique had statistically superior pullout strength (P < .0001) compared with the horizontal mattress and mulberry knot techniques, which were statistically similar. There were significant differences (P < .0001) between suture types, with 1-PDS proving best compared with 0-PDS, which was stronger than 2-0 Ethibond. Selection of suture material had the greatest impact on vertical mattress load to failure and was not important to the strength of the other techniques.  相似文献   
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