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121.
Heat and water vapour transfer of protective clothing systems in a cold environment,measured with a newly developed sweating thermal manikin 总被引:1,自引:0,他引:1
Fukazawa T Lee G Matsuoka T Kano K Tochihara Y 《European journal of applied physiology》2004,92(6):645-648
A moveable sweating thermal manikin has recently been developed. Thermal and water-vapour resistances of three kinds of cold-protective clothing ensembles, laminated with polytetrafluoroethylene, polyurethane and without a laminate were measured, with the aid of the manikin in a cold environment of 5°C with a relative humidity of 70% and an air velocity of around 1.5 m s–1. Two sweating rates of 65 and 130 g m–2 h–1 were employed. Supplied heat fluxes in both of the sweat rates ranged from 350 W m–2 to 400 W m–2. To maintain a comfortable condition, the skin wettedness (w) (mean weighted value) had to be kept at 0.6. The measurements obtained from the manikin when testing the three ensembles were w=0.3 (approximately) for the low sweat rate and w0.6 for the high sweat rate, irrespective of the property differences among the ensembles. In addition, the condensation in the ensembles in comparison with those calculated from an analytical equation is discussed. Condensation mass fluxes in the ensembles obtained byexperiment and those from the calculation agreed sufficiently well. Thus, distribution of the condensation in the ensembles was estimated using the equation. 相似文献
122.
我国福建汉族人HSP70基因多态性分析 总被引:1,自引:0,他引:1
目的了解福建省汉族人HSP70基因多态性分布,进而为探讨HSP70基因多态性与疾病的相关性提供遗传背景资料。方法应用聚合酶链反应技术、限制性内切酶分析检测了127名福建汉族正常人的HSP70基因3个多态性位点,并比较了部分不同地区和人群之间的基因型与等位基因频率。结果福建汉族人HSP70-1基因型(GG,GC和CC)分布频率分别是55.1%、40.2%和4.7%;HSP70-2基因型(从,AG和GG)分布频率分别是44.1%、铝.8%和6.9%;HSP70-hom基因型(Tr,TC和CC)分布频率分别是59.8%、37.0%和3.2%;HSP70-1等位基因频率G和C分别是75.2%和24.8%;HSP70-2等位基因频率A和G分别是68.5%和31.5%;HSP70-hom等位基因频率T和C分别是78.3%和21.7%。福建汉族人HSP70-1的基因型分布和等位基因频率同日本、墨西哥人群比较差异无统计学意义,与美国和西班牙人比较,差异有统计学意义(P〈0.01)。福建汉族人HSP70-1的GG纯合型(55.1%)显著高于美国(42.6%)和西班牙(33.0%)人群;福建汉族人HSP70-2的基因型分布和等位基因频率与日本人比较差异无统计学意义,与墨西哥、美国和西班牙人群比较,差异有统计学意义(P〈0.05),福建汉族人HSP70-2的AA纯合型(44.1%)高于墨西哥(23.O%)、美国(38.8%)和西班牙(20.O%)人群;福建汉族人群的HSP70-hom基因型和等位基因频率分布同日本、墨西哥、美国和西班牙人群的基本一致,差异无统计学意义,福建汉族人群的HSP70基因型和等位基因频率分布同中国台湾汉族人基本一致,差异无统计学意义,与武汉地区汉族人某些位点存在差异。结论福建汉族人HSP70基因多态性分布不同于某些地区的人群,具有种族和地区差异。 相似文献
123.
Elabbassi EB Belghazi K Delanaud S Libert JP 《European journal of applied physiology》2004,92(6):679-682
Keeping premature newborns warm is crucial for their survival. Their ability to prevent excessive heat loss to the environment and to control their body temperature is limited. The risk of hypothermia is particularly important for low-birth-weight newborns with a large body surface area in relation to their mass of heat-producing tissues. The present study was performed to assess the body heat loss difference between small and large body-size premature newborns using two anthropomorphic thermal manikins of premature newborns of 900 g and 1,800 g (respective body surface areas of 0.086 and 0.150 m2). The dry heat loss from the six body segments of the small manikin (S) was measured and compared with that of the large manikin (L). The two manikins were exposed to five different environmental temperatures ranging between 29 and 35°C in a single-walled, air-heated closed incubator. The magnitudes of heat loss decreased significantly by 20.4% between the two manikins [small manikin 110.1 (44.3) W/m2 vs large manikin 87.6 (25.8) W/m2, mean values with one standard deviation]. The results obtained from the comparison of the heat loss measures from the two manikins confirm the fact that the heat loss increases with an increase in the ratio of the body surface area to body mass. The thermal manikin appears to provide an accurate method for the assessment of thermal conditions in neonatal care. 相似文献
124.
Angela Kaysel Cruz Hernán F. Terenzi João A. Jorge Héctor F. Terenzi 《Current genetics》1988,13(5):451-454
Summary We investigated the heat shock response of the adenylate cyclase deficient mutant cr-1 (crisp) of Neurospora crassa. This strain was observed to be much more resistant to a lethal temperature of 50 °C than the wild type. This constitutive thermotolerance was absent in cr-1 conidiospores raised on cyclic AMP (cAMP, 2.5 mM) supplemented solid medium, but was partially restored when the conidiospores were germinated at 30 °C, a temperature which fails to induce thermotolerance in the wild-type strain. Two other crisp-like Neurospora mutants, cr-2 and cr-3 which, in contrast to cr-1, contain normal levels of cAMP, did not exhibit the thermotolerance phenomenon observed for cr-1. A cr-1, pe, fl (crisp-microconidial) strain also lacked the ability to tolerate a lethal heat treatment. Our results demonstrate that the adenylate cyclase deficient cr-1 mutant of Neu-rospora crassa expresses a constitutive thermotolerant phenotype as a consequence of its primary genetic defect: low levels of cAMP. 相似文献
125.
The response of heat shock proteins 25 and 72 to ischaemia in different kidney zones 总被引:1,自引:0,他引:1
A. Schober E. Müller K. Thurau F. X. Beck 《Pflügers Archiv : European journal of physiology》1997,434(3):292-299
Induction of heat shock proteins (HSPs) following cell injury contributes to the protection of vital cell functions. It was,
therefore, of interest to study the effects of transient renal ischaemia on the abundance and distribution of two HSPs, HSP25
and HSP72, in renal tissue using Western-blot techniques. Analyses were performed on the supernatant (HSP25, HSP72) and pellet
(HSP25) of homogenates obtained from cortex (CX) and outer (OM) and inner (IM) medulla of the rat kidney immediately after
60 min of ischaemia followed by varying periods of reperfusion. Ischaemia of the left kidney caused HSP25 contents to decrease
in CX, OM and IM by 73, 89 and 54% respectively, compared with the corresponding zones of the contralateral control kidney.
This initial decrease in supernatant HSP25 was accompanied by an increased abundance of HSP25 in the pellet. Following reperfusion,
HSP25 contents in the supernatant gradually increased in CX and OM, reaching, after 24 h, values that were 5.4- and 2.5-fold
higher, respectively, than those in the control kidneys. After 7 or 14 days of reperfusion, HSP25 contents had not completely
normalised in CX, but had reached control levels in OM. In IM, the HSP25 content remained below control throughout the entire
reperfusion period. HSP72 (supernatant) was below the detection limit in the CX of the control kidney. Similar to the level
of HSP25, that of HSP72 was also markedly lower in OM and IM immediately after ischaemia. The intrarenal distribution of HSP72
and the sequence of zonal changes in HSP72 contents were similar to those observed for HSP25. These results are compatible
with the view that, during ischaemia and the initial reperfusion period, HSP25 migrates from the cytoplasmic compartment (supernatant)
into the nucleus and/or associates with cytoskeletal structures. The observation that both HSP25 and HSP72 are transiently
induced in CX and OM, but not in IM, may be explained by the fact that, while all kidney cells are exposed to ischaemic stress,
only inner medullary cells experience a major postischaemic attenuation of osmotic stress.
Received: 11 February 1997 / Received after revision and accepted: 26 March 1997 相似文献
126.
U波倒置40例,其中孤立性U倒16例(40%),复合性U倒24例(60%)。U波倒置常见于左心前导联V_5V_6,呈现左室肥厚及负荷加重,心电图示“左室劳损”型。U波倒置严重合并症,除心力衰竭外,还有急性心肌梗塞和室性期前收缩。笔者认为,通过本文分析,UV_5倒置对临床诊断冠心病,高血压等是有价值的。 相似文献
127.
Hashaam Akhtar Samar Akhtar Fazal-Ul Rahman Maham Afridi Sundas Khalid Sabahat Ali Nasim Akhtar Yousef S Khader Hamaad Ahmad Muhammad Mujeeb Khan 《JMIR Public Health and Surveillance》2021,7(5)
BackgroundSince the first reports of COVID-19 infection, the foremost requirement has been to identify a treatment regimen that not only fights the causative agent but also controls the associated complications of the infection. Due to the time-consuming process of drug discovery, physicians have used readily available drugs and therapies for treatment of infections to minimize the death toll.ObjectiveThe aim of this study is to provide a snapshot analysis of the major drugs used in a cohort of 1562 Pakistani patients during the period from May to July 2020, when the first wave of COVID-19 peaked in Pakistan.MethodsA retrospective observational study was performed to provide an overview of the major drugs used in a cohort of 1562 patients with COVID-19 admitted to the four major tertiary-care hospitals in the Rawalpindi-Islamabad region of Pakistan during the peak of the first wave of COVID-19 in the country (May-July 2020).ResultsAntibiotics were the most common choice out of all the therapies employed, and they were used as first line of treatment for COVID-19. Azithromycin was the most prescribed drug for treatment. No monthly trend was observed in the choice of antibiotics, and these drugs appeared to be a random but favored choice throughout the months of the study. It was also noted that even antibiotics used for multidrug resistant infections were prescribed irrespective of the severity or progression of the infection. The results of the analysis are alarming, as this approach may lead to antibiotic resistance and complications in immunocompromised patients with COVID-19. A total of 1562 patients (1064 male, 68.1%, and 498 female, 31.9%) with a mean age of 47.35 years (SD 17.03) were included in the study. The highest frequency of patient hospitalizations occurred in June (846/1562, 54.2%).ConclusionsGuidelines for a targeted treatment regime are needed to control related complications and to limit the misuse of antibiotics in the management of COVID-19. 相似文献
128.
目的:观察肾盂肾下盏夹角及结石大小对结石排净率的影响。方法:选择68例肾下盏结石患者,通过IVU影像,测量夹角与结石直径,并经ESWL治疗,随访2月,观察结石排空情况。结果:68例患者,结石完全排出42例,总的排石排空率为61.7%。结论:提示肾盂肾下盏夹角,结石直径对结石排净率有重要影响。 相似文献
129.
The gold-standard method for diagnosing arteriogenic erectile dysfunction (AED) is the penile Doppler ultrasonography. We proposed a novel method for predicting AED using ultrasonic shear wave elastography (SWE) considering that the former was invasive and variable. A total of 98 male patients were enrolled in our study, referred for ED between December 2018 and October 2020. For comparison, we also included 42 volunteers from the Healthy Physical Examination Center of our hospital. The Penile Doppler Ultrasonography (PDU) and SWE were performed for all patients with the intracavernosal injection (ICI). We named three groups as AED group, nonvascular ED group and healthy controls group. No statistically significant differences were found among the three groups in terms of demographic and clinical characteristics. There were no significant differences in IIEF-5 between AED and nonvascular ED. A significant (r = 0.642, p < 0.0001) positive correlation between flaccid and erectile SWE was observed. With a cut-off value of 13.45 KPa, the area under curve, specificity, and sensitivity of the SWE values under the flaccid state in distinguishing AED from healthy subjects were 0.867, 0.786 and 0.896 respectively. The SWE value in the flaccid state can distinguish the AED from healthy subjects. 相似文献
130.