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21.
The model biological organisms Drosophila melanogaster and Drosophila virilis have been utilized to assess effects on apoptotic cell death of follicles during oogenesis and reproductive capacity (fecundity) decline. A total of 280 different experiments were performed using newly emerged flies exposed for short time daily for 3–7?d to various EMF sources including: GSM 900/1800?MHz mobile phone, 1880–1900?MHz DECT wireless base, DECT wireless handset, mobile phone-DECT handset combination, 2.44?GHz wireless network (Wi-Fi), 2.44?GHz blue tooth, 92.8?MHz FM generator, 27.15?MHz baby monitor, 900?MHz CW RF generator and microwave oven’s 2.44?GHz RF and magnetic field components. Mobile phone was used as a reference exposure system for evaluating factors considered very important in dosimetry extending our published work with D. melanogaster to the insect D. virilis. Distance from the emitting source, the exposure duration and the repeatability were examined. All EMF sources used created statistically significant effects regarding fecundity and cell death-apoptosis induction, even at very low intensity levels (0.3?V/m blue tooth radiation), well below ICNIRP’s guidelines, suggesting that Drosophila oogenesis system is suitable to be used as a biomarker for exploring potential EMF bioactivity. Also, there is no linear cumulative effect when increasing the duration of exposure or using one EMF source after the other (i.e. mobile phone and DECT handset) at the specific conditions used. The role of the average versus the peak E-field values as measured by spectrum analyzers on the final effects is discussed.  相似文献   
22.
Existing wireless coal mine environmental monitoring system has large transmissions of redundancy data. Monitoring and treatment of multiple environmental parameters are mutually independent, with low instantaneity and reliability. To solve the above problems, this paper designs the coal mine environmental monitoring system based on multi-agent, taking advantages of the harmony and intelligence of the multi-agent technology. This system designs the environmental monitoring agent from both hardware and software aspects which can cooperate mutually and work harmoniously between each other. Thus, the quantity of transmission of data can be reduced, which optimizes the structure of the coal mine environmental monitoring system. Results of simulation experiments prove that the multi-agent-based coal mine environmental monitoring system can reduce the transmission delay and packet loss probability of data and enhance the instantaneity and reliability of data transmission in the system. Therefore, the new system is more applicable and advanced in the field of coal mine environmental monitoring.  相似文献   
23.
An account is given of the use of Enteromorpha to monitor zinc, cadmium, mercury and lead pollution in six estuaries and the British North Sea coast. The ranges for each element were: Zn, 19–437 µg g–1; µg g–1 Cd, 0.07–4.8 µg g–1; Hg, 0.02–0.23 µg g–1. It is suggested that tissue analysis of Enteromorpha is one of the most useful biological techniques available in estuaries for pin-pointing aqueous (as opposed to sediment) metal contamination, and also for providing data suitable for world-wide comparisons. Provisional values are given for concentrations corresponding to moderate and high pollution.Deceased  相似文献   
24.
Tendons transmit contractile muscular force to bone to produce movement, and it is believed cells can generate endogenous forces on the extracellular matrix to maintain tissue homeostasis. However, little is known about the direct mechanical measurement of cell-matrix interaction in cell-generated human tendon constructs. In this study we examined if cell-generated force could be detected and quantified in engineered human tendon constructs, and if glycosaminoglycans (GAGs) contribute to tendon force transmission. Following de-tensioning of the tendon constructs it was possible to quantify an endogenous re-tensioning. Further, it was demonstrated that the endogenous re-tensioning response was markedly blunted after interference with the cytoskeleton (inhibiting non-muscle myosin-dependent cell contraction by blebbistatin), which confirmed that re-tensioning was cell generated. When the constructs were elongated and held at a constant length a stress relaxation response was quantified, and removing 27% of the GAG content of tendon did not alter the relaxation behavior, which indicates that GAGs do not play a meaningful role in force transmission within this system.  相似文献   
25.
为加强医院门诊血液透析事件的监控,设计开发了门诊血液透析事件监测软件,对血液透析事件进行实时监测和统计分析,实现了门诊血液透析事件的信息化监测和数据的即时共享,提高了医院感染目标性监测和干预的质量和效率。  相似文献   
26.
徐湘盛  封黎明 《蛇志》1991,3(3):43-44
本文通过116例二尖瓣决窄分离术中监护和输液,从中体会到术中监护是心脏手术成功必不可少的条件。只有做好术中监护,才能及时了解病情发展,正确指导复苏和输液,提高手术的安全系数。  相似文献   
27.
ABSTRACT The nocturnal activity of burrow‐nesting seabirds, such as storm‐petrels and shearwaters, makes it difficult to study their incubation behavior. In particular, little is known about possible differences in the incubation behavior of adults at successful and unsuccessful nests. We combined the use of passive integrated transponder (PIT) technology and nest‐temperature data loggers to monitor the incubation behavior of 10 pairs of Leach's Storm‐Petrels (Oceanodroma leucorhoa). The mean incubation bout length was 3.31 ± 0.59 (SD) days for individual adults at successful nests (N= 4) and 1.84 ± 1.16 d for individuals at unsuccessful nests (N= 6). Mean bout length for pairs in successful burrows (3.51 ± 0.56 d) did not differ significantly (P= 0.07) from that for pairs in unsuccessful burrows (1.80 ± 1.20 d), perhaps due to one failed nest with a high mean bout length (4.15 d). The total number of incubation bouts per parent (4.3 ± 1.9 bouts) did not differ with hatching success. Adults whose nests failed repeatedly exhibited truncated incubation bouts (< 12 h) prior to complete nest failure and were more likely than successful parents to make brief visits to nearby, occupied nesting burrows. Our results suggest that the decision by Leach's Storm‐Petrels to abandon a nest is not an abrupt one. Rather, failed nesting attempts may be characterized by truncated incubation bouts where individuals pay the energetic cost of travel to and from the burrow, but do not remain long enough to successfully incubate the egg.  相似文献   
28.
Intraoperative measurement of hip posture is the basis for assessing hip range of motion (ROM) and predicting postoperative functional limits allowable for activities of daily living. Although computer navigation for total hip arthroplasty (THA) has improved the accuracy of intraoperative ROM evaluation, it has not gained widespread popularity due to its complex and time-consuming protocol. We therefore developed an inertial measurement unit-based hip smart trial system (IMUHST) for intraoperative monitoring of hip posture. An in vitro validation experiment was conducted using bone models with a three-dimensional measurement model as the reference standard. The absolute mean error, Bland – Altman analysis and intra-class correlation coefficient demonstrated that the validity and reliability of this system meets the requirement for clinical application. Given that monitoring posture is the basis for evaluating the direction(s) of potential impingement, subluxation and dislocation, the IMUHST is a promising development direction of computer assisted surgery in THA.  相似文献   
29.
摘要 目的:观察阿戈美拉汀联合舍曲林治疗抑郁症伴失眠的疗效及对睡眠质量评分、多导睡眠(PSG)监测参数和血清神经递质的影响。方法:选取2020年4月~2021年12月期间来贵州省第二人民医院就诊的80例抑郁症伴失眠患者作为观察对象,采用随机数字表法分为实验组和对照组各40例,对照组患者接受舍曲林治疗,实验组患者接受阿戈美拉汀联合舍曲林治疗,对比两组疗效、匹兹堡睡眠质量指数(PQSI)评分、PSG相关指标参数、汉密尔顿抑郁量表(HAMD)评分、血清神经递质水平变化,记录两组治疗期间不良反应发生情况。结果:实验组的临床总有效率为90.00%(36/40),高于对照组的67.50%(27/40),差异有统计学意义(P<0.05)。两组治疗8周后PSQI、HAMD评分均下降,且实验组的变化程度大于对照组(P<0.05)。两组治疗8周后睡眠总时间(TST)、睡眠效率(SE)、非快速眼动睡眠阶段3+4的百分比(SWS)、快速眼动睡眠阶段睡眠时间(RT)增加,非快速眼动睡眠阶段1的百分比(S1)、非快速眼动睡眠阶段2的百分比(S2)减少,且实验组的变化程度大于对照组(P<0.05)。两组治疗8周后去甲肾上腺素(NE)、5-羟色胺(5-HT)水平均升高,且实验组的升高程度大于对照组(P<0.05)。两组不良反应发生率组间对比未见差异(P>0.05)。结论:阿戈美拉汀联合舍曲林治疗抑郁症伴失眠,可有效改善抑郁和失眠症状,同时还可调节血清神经递质水平,是一个较为安全可靠的治疗方案。  相似文献   
30.
针对心电信号处理过程中的心电信号数字滤波、心电波形的动态显示、心电数据存储等问题,阐述了3个可用于心电信号实时处理的方法:一是运用滤波器频谱的周期性减少了滤波器系数个数,提高了运算速度,并根据卷积公式特点实现了数字滤波的实时性;二是运用基于内存虚拟屏幕技术实现心电波形动态显示,解决了屏幕闪烁和绘图不连续问题;三是采用嵌入式数据库SQLITE实现了心电数据存储。所有方法均考虑实时性要求,并已成功用于课题组开发的便携式心电监护仪,效果较为理想,具有很强的实用价值。  相似文献   
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