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41.
Summary The effects of atenolol (2–5 mmol/l), sotalol (1–2 mmol/l) and pamatolol (0.1–1 mmol/l), together with N-tertiary butyl phenoxypropanolamines with o-methyl (D-2T: 50–100 mol/l) m-methyl (D-3T: 50–100 mol/l) and p-methyl (D-4T:100–200 mol/l) group as well as with o,p-methyl groups (D-24T) (50–100 mol/l) on action potentials (APs) were investigated in isolated guinea-pig papillary muscles. All the drugs in these concentrations produced a concentration-dependent reduction of the maximum upstroke velocity (V max). The reduction ofV max in premature APs induced by stimuli interpolated between the basic driving rate of 0.25, 0.1 or 0.027 Hz decayed exponentially during diastolic intervals. The time constants of these decay processes for atenolol, pamatolol and sotalol ranged between 260–541 ms, those for D-3T and D-4T between 655–1,166 ms, and D-2T and D-24T between 1,565–1,931 ms. A drug which provided larger values caused the reduction ofV max in a wider range of the frequency. With respect to the aryloxypropanolamine derivatives so far studied (Sada and Ban 1980, 1981 a, b; Sada et al. 1983) fairly good correlations were found as follows: between logn-octanol/water partition coefficient (logP) and ED20 at 0.25 Hz, ED30 at 1 and 4 Hz for 11–14 compounds; between logP and resting block, between molecular weight and A o c i.e. the value extrapolated to the time of APD90 of the conditioning response relative to the predrugV max value which may represent a fraction of channels blocked per AP for 100 mol/l of 20–22 compounds. With respect to 8 compounds with methyl substituents in the benzene ring or amine part the ortho methyl group makes a major contribution to increase the resting block and to increase log values.  相似文献   
42.
The marital adjustment of patients with psychogenic pain disorder was evaluated and compared with a matched group of patients with other neurotic disorders. Pain patients spouses were found to have better marital adjustment and less psychiatric morbidity than the spouses of neurotic patients. These findings are discussed in terms of the concepts of "sick role homeostasis" and "tertiary gain".  相似文献   
43.
The COVID-19 pandemic has had a significant impact on populations at an economic, health, and on an interpersonal level, it is still unclear how it has affected health-risk behaviors, such as comfort food consumption over time. This study longitudinally examines the effect of the perceived impact of COVID-19 on comfort food consumption and whether this effect is mediated by emotional distress. A convenience sample of 1048 students and university staff (academic and non-academic) from two universities completed monthly online surveys during the COVID-19 pandemic across six waves (W; W1 to W6). Participants reported their perceived impact of COVID-19 (economic, interpersonal, and health), comfort food consumption, and emotional distress (DASS-21). Using structural equation models, we found an indirect longitudinal effect of the perceived impact of COVID-19 (W1) on comfort food consumption (W3 to W6) through increased emotional distress (W2). The perceived negative impact of COVID-19 on comfort food consumption was fully mediated by the emotional distress during the first waves (W3 and W4), ending in a partial mediation in the last waves (W5 and W6). These findings contribute to disentangling the mechanisms by which the perceived impact of COVID-19 affects comfort food consumption over time, and highlight the role of emotional distress. Future interventions should address comfort food consumption by focusing on handling emotional distress during a crisis.  相似文献   
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45.
目的 了解广西省医用电子直线加速器设备性能的质量控制水平,为卫生行政部门研究制定医用电子直线加速器卫生标准和质量控制检测规范提供技术支持。方法 采用随机抽样方法,对广西省部分医用电子直线加速器进行质控检测。结果 2017—2019年累计检测118台次加速器,加速器质控检测(包括X射线和电子束)总初检合格率为56.8%,总复检合格率为96.6%;二级、三级医院加速器质控检测初检合格率分别为32.0%、62.2%,差异有统计学意义(P < 0.05),初检合格率最低的指标是辐射剂量示值误差,其次是辐射野均整度。结论 广西省医用电子直线加速器质量控制水平有待提高;卫生行政部门应进一步加强对加速器质控检测的监督,定期开展加速器质控检测。  相似文献   
46.
通过运用仿真人体模型对松果体区靶病灶直线加速器多聚弧照射的监测,论证直线加速器作为放射外科工具治疗颅内病变的科学性,探讨有关辐射参数对剂量分布的影响。作者认为,直线器放射外科可实现与伽玛马相似的剂量分布,同是神经外科安全有效的治疗技术,准直器孔径越小,照射范围越大,则剂量梯度即越大,剂量分布越理想;靶区最大剂量对上器孔径有相当高的依赖性,本文还就合理的照射弧范围及边缘处方剂量作了讨论。  相似文献   
47.
心房纤颤(atrial fibrillation, AF)是临床上最常见的心律失常之一,也是心血管疾病发病率和死亡率增加的重要原因。心外膜脂肪(epicardial adipose tissue, EAT)是位于脏层心包和心肌之间的一种特殊脂肪组织,研究表明EAT参与AF的发生与维持,但是具体机制尚未得到完全阐释。EAT来源的脂肪干细胞(adipose-derived stromal cells, ADSCs)分泌的细胞外囊泡(extracellular vesicles, EVs) 近年来受到重视。该文主要从EAT特点、定量检测及其与心肌结构与电重构的关系,特别是EVs对AF发生的影响等方面进行综述,以期进一步认识AF的发病机制,为今后的治疗提供新的思路。  相似文献   
48.
To determine the optimum dose of epidural morphine for postoperative pain control, 0.5–4.0mg of morphine was administered to 198 patients who had undergone operations on lower abdomen or lower extremities under continuous epidural anesthesia. Analgesic effect of morphine and incidence of nausea or vomiting were studied using linear discriminant analysis. As explanatory variables, age and dose of morphine were statistically significant in discriminating analgesic effect of morphine. Among indices for physique of patients, height was the most useful for predicting the analgesic effect. The dose which made the discriminant function zero corresponded to the minimum effective dose (MED) of morphine and it was expressed as follows; MED (mg·meter–1) = –0.0107 × age + 1.85. Predicting the incidence of nausea or vomiting in relation to the dose of morphine did not reach a level of statistical significance.(Ochi G, Yamane C, Arai T: Optimum dose of epidural morphine for postsurgical analgesia. J Anesth 4: 35–39, 1990)  相似文献   
49.
Compared with the nucleic acid amplification test (NATT), the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) rapid antigen self-testing (RAST) has advantages in speed and convenience. However, little is known about people's acceptance and influencing factors for SARS-CoV-2 RAST. A cross-sectional study was conducted from April 21 to 30, 2022 in China. The χ2 test and multivariate logistic regressions were used to identify the influencing factors. The structural equation model was used to test the extended protective motivation theory (PMT) model hypotheses. Among the total of 5107 participants, 62.5% were willing to accept the SARS-CoV-2 RAST. There were significant differences in acceptance among different residences (p < 0.001), educational level (p < 0.001), occupation (p < 0.001), monthly income (p < 0.001), travel frequency (p < 0.05), and feelings about NATT (p < 0.001). Response efficacy (β = 0.05; p = 0.025) and self-efficacy (β = 0.84; p < 0.001) had a positive effect, while response cost showed a negative effect (β = −0.07; p < 0.001). The public's major concerns about SARS-CoV-2 RAST are its reliability, testing method, price, and authority. Overall, a moderate intention to use SARS-CoV-2 RAST was found among the Chinese population. The extended PMT can be used for the prediction of intention to accept the RAST. We need to take measures to increase people's acceptance of SARS-CoV-2 RAST.  相似文献   
50.
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