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This study compared the effects of pre-exercise cooling with control water immersions on exercise-induced thermal loads derived from steady-state submaximal exercise. Eight healthy male participants [mean (SEM) age 29 (1) years, maximal oxygen uptake 3.81 (0.74) l·min–1, and body surface area 1.85 (0.11) m2] took part in experiments that included 30 min of baseline data collection [ambient temperature 21.3 (0.2°C)], 30 min of immersion in water to the level of the supra-iliac crest [water temperatures of 35.1 (0.3)°C for thermoneutral and 17.7 (0.5)°C for precooled treatments], and 60 min of cycling exercise at 60% of maximal oxygen uptake. No significant differences were noted during exercise in net mechanical efficiency, metabolic rate, O2 pulse, or ratings of perceived exertion between the two treatments. Precooling resulted in a significant negative body heat storage during immersion and allowed greater heat storage during exercise. However, net body heat storage for the entire protocol was no different between treatments. Cooling significantly lowered rectal, mean skin, and mean body temperatures as well as more than doubling the exercise time until a 0.5°C rectal temperature increase was observed. The cooling trial significantly delayed onset of sweating by 19.62 min and decreased sweat rate by 255 ml·h–1 compared to control. Thermal and sweat sensation scores were lower after the cooling treatment compared to control. These data suggest that lower-body precooling is effective at decreasing body heat storage prior to exercise and decreases reliance on heat dissipation mechanisms during exercise. Therefore, this unique, well-tolerated cooling treatment should have a broader application than other precooling treatments. Electronic Publication  相似文献   
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Zusammenfassung Es wird in Kürze der Stand des Untersuchungsverfahrens bei der Erforschung des leicht abspaltbaren Eisens im Serum besprochen, sowie die ungeklärte und schwierige Lage der klinischen Bearbeitung dieses Gebietes im allgemeinen dargelegt. Es folgt eine Schilderung der bei der eigenen Arbeit verwandten Barkanschen Methode und der mit ihr gemachten Erfahrungen.Aus der Darstellung der Ergebnisse und den Tabellen am Schluß, die einen Überblick über Untersuchungsweise und klinische Befunde der verschiedenen Untersucher bieten sollen, geht ein widerspruchsvolles Bild hervor, aus dem auch auf die Schwierigkeit und teilweise Unzuverlässigkeit der Methoden geschlossen werden darf. Die hohe Fehlergrenze, die ich mit der Barkanschen Methode hatte, zeigt dasselbe.Im übrigen darf man wohl aus den Zusammenstellungen folgern, daß zwischen dem Serumeisen und dem Blutfarbstoff kein unmittelbarer Zusammenhang besteht, ein Schluß, zu dem sowohl Kliniker, wie Chemiker auch im einzelnen schon gekommen sind, der jedoch nicht unwidersprochen ist.Herrn Prof.Schottmüller danke ich für die Überlassung des erforderlichen Materials an seiner Klinik, Herrn Prof.Schumm für die freundliche Überlassung eines Arbeitsplatzes und seine liebenswürdige Unterstützung meiner Arbeit, sowie Fräulein Dr.Mertens und den Herren Dr.Budelmann und Dr.Dohmen für ihre freundliche Hilfsbereitschaft.  相似文献   
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Five wild-type strains of tetracycline-resistantUreaplasma urealyticum and one tetracycline-sensitiveUreaplasma urealyticum strain were tested for presence of thetetM sequence by hydridization assays. Two sorts of probes were used, a plasmid containing thetetM fragment and thetetM fragment alone. Two sorts of label were used for each, digoxigenin and radio-labelling. Both purified DNA at various concentrations and non-purified DNA in the pellet from a 10 ml culture were used as targets. The digoxigenin-labelled whole plasmid probe was as specific as the insert alone when hybridized with non-purified DNA, and was more sensitive than radio-labelled probes.  相似文献   
15.
Syndecan-4 and its cytoplasmic binding partner, synectin, are known to play a role in FGF-2 signaling and vascular growth. To determine their roles in coronary artery/arteriolar formation and growth, we compared syndecan-4 and synectin null mice with their wild-type counterparts. Image analysis of arterioles visualized by smooth muscle alpha-actin immunostaining revealed that synectin (-/-) mice had lower arteriolar length and volume densities than wild-type mice. As shown by electron microscopic analysis, arterioles from the two did not differ in morphology, including their endothelial cell junctions, and the organization and distribution of smooth muscle. Using micro-computer tomography, we found that the size and branching patterns of coronary arteries (diameters > 50 microm) were similar for the two groups, a finding that indicates that the growth of arteries is not influenced by a loss of synectin. Syndecan-4 null male mice also had lower arteriolar length densities than their gender wild-type controls. However, female syndecan-4 null mice were characterized by higher arteriolar length and volume densities than their gender-matched wild-type controls. Thus, we conclude that both synectin and syndecan-4 play a role in arteriolar development, a finding that is consistent with previous evidence that FGF-2 plays a role in coronary arterial growth. Moreover, our data reveal that gender influences the arteriolar growth response to syndecan-4 but not to synectin.  相似文献   
16.
This is the first application of flow cytometry for the detection of lamina propria plasma cells and their intracellular immunoglobulins in patients with inflammatory bowel disease compared to healthy controls. The study has been focused on the distribution of IgA, IgG, IgM and the four IgG subclasses. Plasma cells were detected as high CD38 positive cells. For fixation and permeabilisation a single step reagent, Ortho Permeafix®, was used.

By flow cytometry, in patients with inflammatory bowel disease compared to healthy controls, a higher percentage of IgG+ cells can be observed, in Crohn's disease also a higher percentage of IgM+ cells. Regarding the IgG subclass distribution, patients with Crohn's disease show an increase in IgG2+ cells, patients with ulcerative colitis an increase in IgG1+ and IgG3+ cells. These results do agree with and expand the results of earlier immunohistochemical and functional studies, which are favoured today. For the determination of lymphocyte subset proportions and the detection of intracellular antigens, flow cytometry provides a useful alternative to well-established immunohistochemical methods. By analysing a larger number of cells, this method is more reproducible and less prone to interobserver variations than immunohistochemistry, which needs the pre-selection of a mucosal area, the microscopic scoring of a limited number of cells and the circumvention of high background staining. The optimized flow cytometric protocol used in this study might be a promising tool for further investigations of various purposes.  相似文献   

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Problem  Anti-beta2-Glicoprotein-1 antibodies (anti-β2GPI-ab) have been related to recurrent miscarriage (RM) with conflicting results. The aim was to evaluate the role of anti-β2-GPI-ab as unique biological marker in RM related to antiphospholipid (aPL).
Method of study  A cohort study that included 59 cases, divided in two groups, was designed: group 1 comprised 43 pregnant women with 'obstetric' antiphospholipid syndrome (APS) and group 2 included 16 cases with similar complaints but only having repeatedly anti-β2-GPI-ab. Previous thrombosis and/or inherited thrombophilia were excluded. Lupus anticoagulant, anticardiolipin antibodies (aCA), anti-β2-GPI-ab, and other autoantibodies were analyzed. Miscarriages, premature births, pre-eclampsia, live births, placental and systemic thromboses were studied.
Results  No differences in previous obstetric complications were detected ( P  =   1.00–0.164). After the treatment, differences in number of obstetric complications were not seen ( P  =   1.00). Live births were similar in two groups (88.4% and 93.7%; P  =   1.00). Placental thrombosis was equal in both groups, 93.3% versus 80% ( P  =   1.00).
Conclusion  These results suggest that anti-β2-GPI-ab may be considered a biological marker for obstetric APS.  相似文献   
20.
According to a growing body of research, betrayal by a romantic partner is increasingly considered as a form of interpersonal trauma. Between 30% and 60% of betrayed individuals experience symptoms of post-traumatic stress disorder (PTSD), depression and anxiety to clinically meaningful levels. From a clinical perspective, this constellation of symptoms can be conceptualized as a stressor-related adjustment disorder. Yet, no qualitative research has examined the association between romantic betrayal and traumatic stress from the perspective of betrayed individuals. Face-to-face semi-structured interviews were conducted with 13 participants who had completed a clinical trial for a new treatment for adjustment disorder stemming from betrayal. Data were analysed using thematic content analysis. Although betrayal was experienced as a shocking and destabilizing event, and participants used trauma or ‘feeling traumatized’ as a metaphor to describe their experience, few had constructed their reaction as traumatic stress. In fact, participants reported experiencing difficulties understanding the intensity of their experience. However, when exposed to external sources (e.g., books and interviews by psychologists and researchers) that used a trauma and PTSD framework to explain the effects of betrayal, participants reported feeling clarity, validation and relief. Findings are discussed in the light of theoretical and clinical implications.  相似文献   
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