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41.
A. G. BIRKS H. IZZARD D. R. MORROLL J. R. PRIOR S. A. TROUP B. A. LIEBERMAN I. L. MATSON 《International journal of andrology》1994,17(6):289-291
The World Health Organization (WHO) laboratory manual (1992) states that assessment of sperm motility can be performed at either 37O C or room temperature (20–24O C). The motility of spermatozoa in 44 semen samples (22 fresh samples and 22 frozen-thawed samples) was assessed at both of these temperatures and a significant difference in the motility profiles was noted, specifically an increase at 37O C in the percentage (expressed here as median and ranges) of spermatozoa with excellent progressive motility and an overall increase in the percentage with total progressive motility. With fresh samples the excellent progressive motility increased from 41 (19–53) to 54 (30–66) and the overall motility from 58.5 (39–74) to 65.0 (40–79). With the frozen—thawed samples the excellent motility increased from 14 (1–33) to 25 (6–45) and the overall motility from 30.5 (14–51) to 33.0 (16–52). As the WHO laboratory manual was published. 'In response to a growing need for the standardisation of procedures for the examination of human spermatozoa' it is proposed that only one temperature for routine analysis should be used, namely 37O C, which may have more physiological relevance and eliminate effects of fluctuations in ambient laboratory temperature. 相似文献
42.
M. S. Avidan N. Jones R. Ing M. Khoosal C. Lundgren & D. F. Morrell 《Anaesthesia》1997,52(11):1073-1076
We sought to determine whether the forced air convection warmers (nine Bair Huggers, Augustine Medical, and one Warm Touch, Mallinkrodt Medical) used in our operating theatres could be a source of microbial pathogens. Agar plates were placed directly in the air stream of the warmers. Four of these grew potentially pathogenic organisms. When the warmers were set to blow through perforated blankets, no growth occurred. Three of the warmers were swabbed and sites of colonisation were found in their hoses. After fixing a microbial filter to the end of the hose, organisms were no longer detectable. We conclude that these warming devices are a potential source of nosocomial infection. They should only be used in conjunction with perforated blankets, should have their microbial filters changed regularly and their hoses sterilised. The inclusion of a microbial filter into the nozzle of the hose could be incorporated into the design of the warmer. 相似文献
43.
S. A. Carter 《Clinical physiology and functional imaging》1991,11(3):253-261
Summary. The effect of changes in local and body temperature on the toe systolic pressures was studied in 20 subjects with and 30 without Raynaud's syndrome in the toes. The pressures were significantly lower in the group with Raynaud's syndrome under all experimental conditions (P < 0·01). The pressures were significantly lower during body cooling than during body warming in both groups (P < 0·01). The mean decrease with body cooling was 58 mmHg in the group with Raynaud's syndrome and 24 mmHg in the control subjects (P < 0·01). During body cooling pressures fell to less than 30 mmHg in 70% of subjects with Raynaud's syndrome and in 3% of the controls. Local cooling from 30 to 10°C during body cooling resulted in a significant mean decrease in pressure of over 40 mmHg in both groups (P < 0·01) and the pressure fell below 30 mmHg in over 90% of the group with and in 26% of those without Raynaud's attacks. The results indicate the importance of body cooling and local temperature in the mechanism of vasospasm in the toes. They are also relevant to the diagnosis of Raynaud's syndrome in the lower limbs and have implications for the testing of patients with arteriosclerotic occlusion since erroneously low pressure values could be obtained in tests when the feet are cold. 相似文献
44.
45.
Using radio-biotelemetry, the timecourse of recovery and sensitivity to ambient temperature (Ta) of the thermogenic response
of methylenedioxymethamphetamine (MDMA or “Ecstasy”) was examined. Ambient temperatures of 17 and 22°C produced very different
response profiles, with the lower temperature producing a hypothermic response to 10 and 15 mg/kg doses of MDMA, and the higher
temperature producing a profound hyperthermia to the same doses. Although the peak responses to the drug had subsided within
5 h of administration, residual effects, in the form of an elevation of body temperature during the “low” phase of the diurnal
cycle, were present for a further 48 h. Long-lasting disruption of the thermoregulatory system following a short series of
MDMA administrations (10 mg/kg once per day for 4 days) was shown by exposing the rats in the undrugged state to a thermoregulatory
challenge, consisting of 60-min exposure to a Ta of 30°C, at 1 week before, and at 4 weeks and 14 weeks after the drug administration.
MDMA-treated rats showed a prolonged hyperthermic response to the challenge at both post-drug intervals compared with fenfluramine-treated
rats and saline-treated controls. Thus, the results indicate both that MDMA’s thermogenic effects are more sensitive to Ta
than previously demonstrated, and that the serotonergic neurotoxicity of the drug may produce long-lasting changes in thermoregulatory
mechanisms.
Received: 7 December 1997/Final version: 23 January 1998 相似文献
46.
J. E NAGTEGAAL G. A KERKHOF M. G SMITS SWART & Y. G VAN DER MEER 《Journal of sleep research》1998,7(2):135-143
In a double-blind placebo-controlled cross-over study, 30 patients with Delayed Sleep Phase Syndrome (DSPS) were included, of whom 25 finished the study. Melatonin 5 mg was administered during two weeks in a double-blind setting and two weeks in an open setting successively or interrupted by two weeks of placebo. The study's impact was assessed by measurements of the 24-h curves of endogenous melatonin production and rectal temperature (n=14), polysomnography (n=22), actigraphy (n=13), sleep log (n=22), and subjective sleep quality (n=25). Mean dim light melatonin onset (DLMO) (±SD), before treatment, occurred at 23.17 hours (±138 min). Melatonin was administered five hours before the individual DLMO. After treatment, the onset of the nocturnal melatonin profile was significantly advanced by approximately 1.5 hour. Body temperature trough did not advance significantly. During melatonin use, actigraphy showed a significant advance of sleep onset and polysomnography, a significant decreased sleep latency. Sleep architecture was not influenced. During melatonin treatment patients felt significantly more refreshed in the morning. These results show that analysis of DLMO of patients suffering from DSPS is important both for diagnosis and therapy. These results are discussed in terms of the biochemistry of the pineal. 相似文献
47.
Thermal cameras are used in research laboratories to measure tissue temperature during laser irradiation. This study was an evaluation of the accuracy of a 3-5 microns thermal camera and two 8-12 microns cameras in detecting the maximum temperatures of small targets. The size of the targets was within the range of laser spot diameters which are used for vessel welding, angioplasty, and dermatology. The response to a sharp thermal edge was measured and analyzed for the three cameras, which had a scanning rate of 30 frames per second. The response of the 3-5 microns camera to reference black body targets of different sizes was also studied. It was found that the detector system required an average of 2.44 microseconds to reach 90% of maximum step response for the 8-12 microns system and 5.85 microseconds for the 3-5 microns system. With a 3 x telescope and a 9.5 inch focal distance close-up lens, the 3-5 microns camera underestimated the temperature of targets smaller than 2.0 mm because of its slow detector response. Although the 8-12 microns camera provides more accurate measurements due to its faster detector response, it still underestimates the temperature of targets smaller than 900 microns, when similar magnification and focal distance are used. Methods to compensate for the inaccuracies are discussed, including empirical correction factors and the inverse filtering technique. 相似文献
48.
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目的通过建立完全性睡眠剥夺的幼鼠模型,探讨短期完全性睡眠剥夺对幼鼠体温调节及生长的影响。方法2005-01-03将上海交通大学附属新华医院儿科研究所12只出生后3周刚断奶的雄性幼鼠,随机分为试验组和对照组。采用小站台水环境的方法对幼鼠进行48h的睡眠剥夺。睡眠剥夺前、24h及48h后,分别进行体温、体重及进食量的监测,并计算日能耗,睡眠剥夺结束后处死幼鼠并对重要脏器进行称量。结果实验结果表明48h睡眠剥夺后,两组幼鼠体温均出现随时间变化特点,在睡眠剥夺24h后增高,48h后出现体温下降;睡眠剥夺后试验组幼鼠体重明显低于对照组,而试验组的进食量在48h后明显多于对照组;在日能量消耗的比较中,试验组在24h睡眠剥夺后的能耗明显高于对照组;睡眠剥夺48h后各器官重量仅双肺重量与体重的比值在两组间存在差异。结论幼鼠完全性睡眠剥夺的早期即出现体温显著下降,较早显现体温调节中枢的失衡,并且体格发育受到显著影响。 相似文献
49.
根据对婴儿培养箱多年的临床使用与维修体会,阐述了婴儿培养箱基本性能要求,并指出现行的此类设备存在的问题,及具体改进方法。 相似文献
50.
Summary In a series of 6 severely head injured patients, intraventricular as well as rectal, bladder and jugular vein temperature is recorded. The relationship between these temperatures in different conditions is evaluated. Intracerebral temperature is 0.5±0.2 °C (mean ± SD) higher than bladder temperature except in conditions such as brain death. It is concluded that rectal temperature is not representative and therefore not a good alternative to the measurement of brain temperature. More data on human intracerebral temperature are mandatory as well as prospective studies correlating intracerebral temperature with final outcome in head injury. 相似文献