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71.
Zusammenfassung Bei der Messung der thermischen Ausdehnung von ungedehnten oder nur wenig gedehnten tierischen Geweben mit Faserstruktur machte sich bisher die thermische Änderung des Auftriebes der Versuchsobjekte in der sie umgebendenRinger-Lösung störend bemerkbar. Um diesen Auftriebsfehler auszuschalten und somit auch an ungedehnten Geweben quantitative Versuche über thermische Ausdehnung anstellen zu können, wurde das optische Lineardilatometer vonWöhlisch dadurch verbessert, daß die Versuchsobjekte durch eine an dem festen Dilatometerarm angebrachte Quarzplatte unterstützt wurden. Die Auswirkung der scheinbaren Gewichtsänderungen auf den Dilatometerzeiger wird hierdurch aufgehoben. Eine Störung des Versuches durch die Platte findet infolge der außerordentlich geringen thermischen Ausdehnung des Quarzes nicht statt.Mit dieser Apparatur wurden erstmalig Versuche zur direkten Bestimmung der thermischen Ausdehnung der Herzmuskulatur vorgenommen. Als Versuchsobjekt dienten Streifenpräparate aus dem Ventrikel von R. esculenta. Die Versuche wurden in einem weiten Bereiche der Dehnungen (0% bis über 50%) angestellt. Es ergab sich eine weitgehende Übereinstimmung im Verhalten des Herzmuskels und des Skeletmuskels: Im Bereiche kleiner Dehnungen ist der lineare thermische Ausdehnungskoeffizient (l. th. A.K.) des erregbaren Herzmuskels negativ; an völlig ungedehnten Streifen ergab sich der Mittelwert =–(3,47±0,78) · 10–5. Durch stärkere Dehnung kommt es wie beim Skeletmuskel und beim Nackenband zu einem Umschlagen des l. th. A.K. zu positiven Werten. Beim toten Herzmuskel ist derl. th. A.K. stets positiv.D 20. 相似文献
72.
Comment on Pfäfflin’s (2008) “Good Enough to Eat” 总被引:1,自引:1,他引:0
Klaus M. Beier 《Archives of sexual behavior》2009,38(2):164-165
73.
74.
Computer-assisted LISS plate osteosynthesis of proximal tibia fractures: feasibility study and first clinical results. 总被引:1,自引:0,他引:1
Paul Alfred Grützner Frank Langlotz Guoyan Zheng Jan von Recum Christina Keil Lutz P Nolte Andreas Wentzensen Klaus Wendl 《Computer aided surgery》2005,10(3):141-149
Fluoroscopy is the most common tool for the intraoperative control of long-bone fracture reduction. Limitations of this technology include high radiation exposure for the patient and the surgical team, limited visual field, distorted images, and cumbersome verification of image updating. Fluoroscopy-based navigation systems partially address these limitations by allowing fluoroscopic images to be used for real-time surgical localization and instrument tracking. Existing fluoroscopy-based navigation systems are still limited as far as the virtual representation of true surgical reality is concerned. This article, for the first time, presents a reality-enhanced virtual fluoroscopy with radiation-free updates of in situ surgical fluoroscopic images to control metaphyseal fracture reduction. A virtual fluoroscopy is created using the projection properties of the fluoroscope; it allows the display of detailed three-dimensional (3D) geometric models of surgical tools and implants superimposed on the X-ray images. Starting from multiple registered fluoroscopy images, a virtual 3D cylinder model for each principal bone fragment is constructed. This spatial cylinder model not only supplies a 3D image of the fracture, but also allows effective fragment projection recovery from the fluoroscopic images and enables radiation-free updates of in situ surgical fluoroscopic images by non-linear interpolation and warping algorithms. Initial clinical experience was gained during four tibia fracture fixations that were treated by LISS (Less Invasive Stabilization System) osteosynthesis. In the cases operated on, after primary image acquisition, the image intensifier was replaced by the virtual reality system. In all cases, the procedure including fracture reduction and LISS osteosynthesis was performed entirely in virtual reality. A significant disadvantage was the unfamiliar operation of this prototype software and the need for an additional operator for the navigation system. 相似文献
75.
76.
Klaus Kuch M.D. F.R.C.P.. Brian J. Cox Ph.D. David M. Direnfeld B.A. 《Journal of anxiety disorders》1995,9(6)
The Accident Fear Questionnaire (AFQ) is a new self-rated scale for PTSD and “accident phobia” (subsyndromal PTSD) after road vehicle accident (RVA). AFQ data from 54 RVA survivors were compared with two clinician-rated and three self-report measures of psychopathology. Diagnoses were based on the DSM-III-R structured clinical interview for PTSD and on DSM-III-R criteria for specific phobia. Diagnostic groups were similar in regards to demographic variables, duration of illness, measures of pain, self-rated physical impairment, and duration of illness. The AFQ had good internal consistency with a Crohnbach's alpha of 0.89 and yielded the largest group differences between PTSD (n = 12), “accident phobia” (n = 14), and neither diagnosis (n = 28). Subjects with PTSD tended to score highest on all self-report measures of psychopathology, followed by “accident phobics”, followed by subjects with neither diagnosis. On the AFQ, this order of severity was preserved after subjects with major depression had been removed from the analysis. Lacking effects from depression and from pain suggest that the AFQ is a specific measure of RVA-related phobic avoidance. 相似文献
77.
78.
Rachelle Bouffard Lily Hechtman Klaus Minde Fiorella Iaboni-Kassab 《Revue canadienne de psychiatrie》2003,48(8):546-554
OBJECTIVE: To evaluate the efficacy of methylphenidate in treating adults with attention-deficit hyperactivity disorder (ADHD), using subjective (self-report) and objective (computerized test) measures. METHOD: This double-blind crossover trial of placebo vs methylphenidate included subjects with childhood and current ADHD symptoms, IQs above 80, no other psychiatric condition explaining their difficulties or requiring other treatment, and no substance abuse in the previous 6 months. We administered 10 mg 3 times daily of medication (that is, placebo or methylphenidate) for 2 weeks. On the final day, subjects completed self-report measures and were tested on computerized tests. We then increased dosage to 15 mg 3 times daily for 2 weeks and administered a complete reassessment on the final day. Following a 1-week washout, we repeated this process on the second medication (that is, placebo or methylphenidate). RESULTS: Thirty adults with ADHD participated. Self-report measures and computerized tests showed significant improvements in ADHD symptoms on methylphenidate, compared with placebo. Other psychiatric symptoms (notably, anxiety and depression) were alleviated with methylphenidate. There was no significant difference between the 2 dosages of methylphenidate. CONCLUSION: Methylphenidate is effective in improving ADHD symptoms in adults with ADHD, is well tolerated, and has minimal side effects. 相似文献
79.
The pharmacokinetic behaviour of the 131-iodine-labelled title compound 3 * and its metabolites in mice was investigated. A two phase, 1st order elimination profile was observed. The second phase is very slow leaving about 35% of radioactivity in the mice even 100h after i.v. injection, because of high affinity to liver and spleen, caused by strong binding of oligoamines to phospholipids of liver and blood cell membranes. The blood-brain-barrier is not passed. No deep compartments were observed. The doses necessary for antithrombotic effects in vivo were calculated from the blood levels to be 20.5–39.7 μmol/kg for a time interval of 1–6 h after administration. 相似文献
80.
Kaisa M. Heiskanen Silvia Münzing Fritz Krombach Kai M. Savolainen 《Archives of toxicology》1997,71(10):627-632
The effects of linoleic acid, linoleic acid anilide, and arachidonic acid on the expression of CD11b/CD18, CD11c/CD18 integrins
and l-selectin on human neutrophils were studied by flow cytometry in a whole blood assay. None of these compounds had any effect
on the basal expression of CD11b, CD11c, or l-selectin in the concentration range of 20–100 μM. However, linoleic acid at a concentration of 1000 μM slightly up-regulated
CD11b and CD11c by a factor of 2.1 and 1.7, respectively. Linoleic acid, linoleic acid anilide, and arachidonic acid did not
affect the formyl-methionyl-leucyl-phenylalanine induced up-regulation of CD11b or CD11c. However, linoleic acid and linoleic
acid anilide slightly inhibited the phorbol myristate acetate (PMA)-induced expression of CD11b, which was decreased by 27
and 21% at concentrations of 100 and 1000 μM, respectively. Likewise, arachidonic acid at 40 μM inhibited the PMA-induced
expression of CD11b by 19%. Our results suggest that linoleic acid, linoleic acid anilide, and arachidonic acid do not dramatically
affect the expression of leukocyte adhesion molecules in a whole blood assay.
Received: 17 February 1997 / Accepted: 5 May 1997 相似文献