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Zusammenfassung An insgesamt 33 gesunden Versuchspersonen im Alter von 18–32 Jahren wurde der Tagesgang der Phasenkoppelung zwischen Herzschlag (R-Zacke im EKG) und Atmung (Inspirationsbeginn) mit dem Koincidenzmeßgerät Synchromet unter verschiedenen Bedingungen untersucht. Bei 10 Probanden erfolgten die Messungen bei Bettruhe in einstündigen Abständen, weitere 10 Personen wurden alle 2 Std im Anschluß an die Koppelungsmessung mit dosierter Tretkurbelarbeit belastet, die übrigen 13 Probanden nur in vierstündigen Abständen, wobei die Phasenkoppelung zweistündlich kontrolliert wurde.In der Ruhegruppe fand sich im Mittel ein signifikanter tagesrhythmischer Gang des Koppelungsgrades mit einem nächtlichen Maximum gegen 1.00 Uhr und einem Minimum zwischen 12.00 und 17.00 Uhr. Die individuellen Tagesamplituden des Koppelungsgrades betragen zwischen 2,8 und 11,6 E (Mittelwert 6,4); sie waren um so größer, je höher das individuelle Tagesniveau von Pulsfrequenz und Puls-Atem-Quotient lag. Die individuellen Tagesmaxima lagen in Ruhe zu 85% in der Nachthälfte (19.00-7.00 Uhr), die Minima zu 75% am Tage (7.00-19.00 Uhr).Bei vierstündlich wiederholter Arbeitsbelastung war die Amplitude im mittleren Tagesgang des Koppelungsgrades, der zwei Gipfel mit 12stündigem Abstand aufwies, signifikant kleiner, bei zweistündlicher Belastungsfolge fehlte sie vollständig. Die individuellen Amplitudenwerte betrugen zwischen 1,3 und 7,5 (Mittelwert 3,1) bzw. 1,1 und 5,5 E (Mittelwert 2,8). Die individuellen Tagesmaxima lagen bei vierstündlicher Belastung noch zu 65% in der Nachthälfte, bei zweistündlicher Belastung nur noch zu 60%, die entsprechende Minimahäufigkeit in der Tageshälfte betrug 58 bzw. 50%. Die Häufigkeitsverteilung der Maxima und Minima war vorzugsweise zweigipfelig mit etwa 12stündigen Gipfelabständen.Im Gegensatz zu der Abschwächung bzw. Unterdrückung der nächtlichen Zunahme des Koppelungsgrades näherte sich das mittlere Frequenzverhältnis aus Puls und Atmung auch in den Belastungsgruppen während der Nacht der Norm 41 an. Der mittlere Tagesgang der Herzfrequenz war bei ähnlichem Niveau aller drei Gruppen nur bei vierstündlicher Belastungsfolge deutlich zweigipfelig mit 12stündigem Gipfelabstand.Die tagesrhythmische Schwankung des Koppelungsgrades wird auf vegetative Umstellungen zurückgeführt, die nicht unmittelbar an den Schlaf gebunden sind. Aus den Befunden bei Arbeitsbelastung wird geschlossen, daß die Phasenkoordination zwischen Herzschlag und Atmung schon durch leichte Arbeitsbelastung nach-haltig gestört wird und längere Erholungszeiten benötigt als Frequenz und Frequenzkoordination beider Rhythmen. Die Phasenkoppelung wird daher als empfindlichster Indicator für die Erholungsvorgänge im Bereich der rhythmischen Koordination angesehen. 相似文献
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The headline compounds were prepared from purified cyanophenylalanines after presenting arylsulfonylglycyl residues, activation of the carboxyl group by formation of the p- nitrophenylester followed by aminolysis and transfer of a cyano in an amidine function. Besides some esters and an acid were synthetized with the basic structure mentioned in the headline . The p-compounds with a cycloaliphatic amide component proved as "tight binding inhibitors". The greatest antithrombin effect shows N alpha-(2- naphthylsulphonylglycyl )-4- amidinophenylalaninpiperidi d with a Ki-value of 6 X 10(-9) mol/l using S-2238 as a substrate. 相似文献
25.
Katharina Voigt Emily Giddens Romana Stark Emma Frisch Neda Moskovsky Naomi Kakoschke Julie C. Stout Mark A. Bellgrove Zane B. Andrews Antonio Verdejo-Garcia 《Nutrients》2021,13(6)
Food homeostatic states (hunger and satiety) influence the cognitive systems regulating impulsive responses, but the direction and specific mechanisms involved in this effect remain elusive. We examined how fasting, and satiety, affect cognitive mechanisms underpinning disinhibition using a novel framework and a gamified test-battery. Thirty-four participants completed the test-battery measuring three cognitive facets of disinhibition: attentional control, information gathering and monitoring of feedback, across two experimental sessions: one after overnight fasting and another after a standardised meal. Homeostatic state was assessed using subjective self-reports and biological markers (i.e., blood-derived liver-expressed antimicrobial protein 2 (LEAP-2), insulin and leptin). We found that participants who experienced greater subjective hunger during the satiety session were more impulsive in the information gathering task; results were not confounded by changes in mood or anxiety. Homeostatic state did not significantly influence disinhibition mechanisms linked to attentional control or feedback monitoring. However, we found a significant interaction between homeostatic state and LEAP-2 on attentional control, with higher LEAP-2 associated with faster reaction times in the fasted condition only. Our findings indicate lingering hunger after eating increases impulsive behaviour via reduced information gathering. These findings identify a novel mechanism that may underpin the tendency to overeat and/or engage in broader impulsive behaviours. 相似文献
26.
The meta-analysis was performed to assess the efficacy and safety of daily oral L-arginine and phosphodiesterase type 5 inhibitors (PDE5Is) alone or combination in treating patients with erectile dysfunction (ED). We performed a search of randomised controlled trials in the following databases: PubMed, EMBASE and Cochrane Library databases. Four articles including 373 patients were studied. Erectile functions were significantly improved in three therapy groups compared with baseline. Patients who received the combination of L-arginine and PDE5Is showed significant improvement compared to those treated with L-arginine and PDE5Is alone, as assessed by sexual function index (p <0.00001 and p =0.005, respectively) and total testosterone (p <0.00001 and p =0.0007, respectively). Furthermore, patients who treated with PDE5Is alone exhibited the better efficacy than those treated with L-arginine alone in respects of sexual function index (p <0.00001) and total testosterone (p =0.0001). However, the combination of L-arginine and PDE5Is had no obvious difference relative to PDE5Is alone in terms of various adverse events (AEs). Conclusively, compared with monotherapy, the combination of L-arginine and PDE5Is showed a greater improvement of sexual function and total testosterone, and did not significantly increase the AEs. Besides, PDE5Is alone revealed a better effect than those treated with L-arginine alone for patients with ED. 相似文献
27.
Jue Chen MD PhD Lei Guo MM Lian Gu MPsy Hui Han MPsy 《The International journal of eating disorders》2021,54(1):102-106
In the past 40 years, the prevalence of eating disorders (ED) in China has shown an increasing trend, leading to an urgent need to develop efficient treatment modes and methods. Since the beginning of the new century, the diagnosis, treatment, and research of ED in China have been under development. This article gives an introduction and commentary on the treatment modes, treatment methods and their applications in ED in China. There are two main treatment forms for ED until now, that is, inpatient treatment and outpatient treatment. Inpatient treatment is recommended as the first choice. Since 2008, clinical psychotherapies such as cognitive behavioral therapy (CBT), dialectical behavioral therapy (DBT), and family-based treatment (FBT), which are effective for pathological symptoms of ED, have been introduced into China and developed clinically. Group CBT and group DBT for patients with ED and group FBT for caregivers might be the most efficient psychotherapy in China nowadays. A multi-family FBT support group could be developed as the basic treatment of ED patients. Although these new types of psychotherapy have observed effectiveness in clinical application, the Randomized Controlled Trials (RCT) are rare and need to be developed. 相似文献
28.
T E Johnson D T Tse G E Byrne A Restrepo C C Whitcomb W Voigt P Benedetto V Curtin 《Ophthalmic plastic and reconstructive surgery》1999,15(3):171-179
PURPOSE: To determine whether molecular genetic analysis of ocular-adnexal lymphoid tumors, combined with histopathology and tumor location, is helpful in predicting which patients will develop systemic lymphoma. METHODS: A combined retrospective and prospective study of 77 patients with ocular-adnexal lymphoid tumors was performed. The tumors were subdivided into conjunctival, orbital, and eyelid lesions, and all were studied using both routine histopathology and molecular genetic analysis. RESULTS: Most lesions (70%) were small cell lymphomas of the mucosa-associated lymphoid tissue type, and the majority of tumors (90%) contained monoclonal or oligoclonal populations of lymphocytes discovered on molecular genetic analysis. Additionally, 72% of tumors exhibiting clonality had more than one gene rearrangement. Fifty-three percent of patients developed extraocular lymphoma sometime during the course of their disease. Patients with gene rearrangements on Southern blot hybridization had a 52% incidence of nonocular disease, compared with 63% of those without rearrangements. Patients with conjunctival tumors had a 37.5% incidence of nonocular disease, those with orbital tumors had a 54% incidence, and those with eyelid tumors had a 100% incidence of nonocular lymphoma. Only two patients died as result of systemic lymphoma. CONCLUSIONS: Most ocular-adnexal lymphoid tumors are lymphomas of the mucosa-associated lymphoid tissue type. The majority of tumors exhibit gene rearrangements on molecular genetic analysis, and this technique was not helpful in predicting which patients would develop nonocular lymphoma. Tumor location did have predictive value: Conjunctival lesions had the lowest incidence of nonocular lymphoma, and lid lesions had the highest incidence. Even with disseminated disease, most patients have a favorable prognosis with treatment. 相似文献
29.
R. Voigt M. Halaska M. John A. Martan P. Voigt W. Michels 《International urogynecology journal》1992,3(2):129-132
The cause of female urethral instability is still controversial. With the help of this retrospective analysis of 1168 continuous long-term recordings of the intraurethral pressure at the maximum point of urethral pressure, the correlation between pressure variations (UPV) and simultaneous bladder instability was investigated. It could be stated that clinically important UPV (more than 15 cmH2O) are found more often in women who suffer from signs of bladder instability (defined as low bladder compliance combined with uninhibited detrusor contractions and/or urinary leakage) than in patients without signs of unstable bladder. 相似文献
30.
Studies of ambulance patients with ischemic heart disease. 11. Selection of patients for ambulance telemetry. 总被引:1,自引:1,他引:0 下载免费PDF全文
One hundred eighty-two of 1,928 patients (9.4 per cent) transported by ambulance during a six-month period in Baltimore had ECGs transmitted. Review of the remaining 1,746 records by two cardiologists indicated that an additional 113 patients should have had their ECGs transmitted because of life-threatening conditions. Of patients with acute ischemic heart disease, 47 had ECG monitoring and 24 did not. There were 22 per cent more Killip 111/1V patients with a 19 per cent higher mortality at three months among the "non-transmitted" patients as compared to the "transmitted" patients, controlling for all other relevant variables. Critical presentations inappropriately affect ambulance staffs' selection of patients for monitoring. 相似文献