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1.
A study was undertaken of all drowning deaths that occurred over a 30-year period from 1988 to 2017 in the urban section of the River Torrens, Adelaide, South Australia, an augmented waterway that runs through the central business district. Autopsy records from Forensic Science South Australia (FSSA) were reviewed. There were 34 drownings (0–5 cases/yr) with 28 males and 6 females (M;F = 4.6:1), with an age range for males of 18-76yrs (mean 42.0; SD 18.0) and for females of 20-84yrs (mean 69.3; SD 24.5). There were 15 (44%) accidents, 11 (32%) suicides, 1 (3%) homicide and 7 (21%) undetermined. Of the 22 cases during or after 1994 with complete toxicology reports, 10 (45%) had a blood alcohol concentration (BAC) of greater than 0.05% (g/100 mL) with an illicit substance detected in 4 (18%) cases: (MDMA (3,4-methylenedioxymethamphetamine), methylamphetamine and THC (delta-9-tetrahydrocannabinol) acid). The presence of various therapeutic drugs was also detected in 10 cases (45%) including temazepam, fluoxetine, diazepam, olanzapine, amitriptyline, carbamazepine, codeine, citalopram and valproate. Although the numbers of cases were not high, the urban portion of the River Torrens had a much higher number of drowning events per kilometre compared to other inland waterways in South Australia such as the Murray River. This is most likely due to the vulnerability that exists for intoxicated individuals in the city from falls into the water and to the availability of the river as a means of suicide to members of the adjacent urban population. 相似文献
2.
As a consequence of the time-varying magnetic field induced by eddy currents, frequency drifting occurs when the sampling window of localized spectroscopy continuously shifts. The frequency drifting and the concomitant phase variations can severely affect spectroscopy results when data are acquired with multiple echo times (TEs), such as in the measurement of glutamate (Glu) concentration using the TE-averaged method. Specifically, the averaged spectra are further broadened and distorted in the presence of residual eddy currents, and editing of the coupled spins of Glu C4 protons is affected, resulting in errors in the measured relative intensity ratio. Postacquisition correction using unsuppressed water as reference can effectively minimize this detrimental effect, as manifested by the significantly enhanced signal intensity. Also, it is demonstrated that the methyl signals of creatine (Cr) at 3.0 ppm and choline (Cho) at 3.2 ppm can be used as internal references in finding frequency and phase disparities between different TEs. 相似文献
3.
目的了解常用消毒剂及自来水对弓形虫速殖子活力的影响。方法将各种消毒剂分别加入等体积含弓形虫速殖子的小鼠腹水中,在不同时间内观察虫体胎盘蓝(trypanblue)着色率及活动率,并将经消毒剂处理不同时间的速殖予接种昆明鼠,观察速殖子能否在接种鼠体内复苏繁殖,导致小鼠死亡。用类似方法观察自来水时速殖子的影响。结果除甲醛个速殖子在常用浓度的不同消毒剂中,lmin月台盘蓝着色率均为100%,活动率为0。经消毒剂处理1min的速殖子接种小鼠后,各组接种鼠(包括甲醛处理组)无一死亡。经自来水处理4h的速殖子接种小鼠后仍能在小鼠体内复苏繁殖,小鼠于接种1wk内全部死亡。结论弓形虫速殖子对常用消毒剂均很敏感;而在自来水中途殖子可保持感染力4h以上。 相似文献
4.
目的:了解改水降氟后地氟病的防治效果。方法:水氟,尿氟测定均为电极法,氟斑牙诊断为Dean‘s法。结果:该村自1985年改饮低氟水,水氟含量由改水前的6.05mg/L降至改水后的0.48mg/L。改水后未出现新的氟骨症患者,8-12岁儿童氟斑牙患病率呈逐年下降趋势,改水后7-15年间氟斑牙病率均已稳定,表明病情得到有效控制,且达到稳定控制状态,结论:坚持长年饮用低氟水,地方性氟中毒就能得到有效控制。 相似文献
5.
Long-term neurotoxicity of chlorpyrifos: spatial learning impairment on repeated acquisition in a water maze. 总被引:2,自引:0,他引:2
Fernando Ca?adas Diana Cardona Eva Dávila Fernando Sánchez-Santed 《Toxicological sciences》2005,85(2):944-951
Organophosphate compounds are cholinesterase inhibitors widely used in agriculture, industry, household products, and even as chemical weapons. Their major mechanism of acute toxic action is the inhibition of acetylcholinesterase, which is responsible for the degradation of the neurotransmitter acetylcholine. An organophosphorus ester-induced chronic neurotoxicity (OPICN) syndrome has been proposed. The OPICN syndrome could result from both long-term exposure to subclinical doses of OPs and after acute poisoning. Development of animal models for the cognitive decline are required and could later help to elucidate the mechanisms involved in this long-term effect on the central nervous system. Previously, we have found performance decrements in a four-trial repeated acquisition spatial task in a water maze. The present study includes two experiments to extend the long-term behavioral effects observed. Rats were injected either once or twice with chlorpyrifos (CPF) and then tested months after in a two-trial repeated acquisition task in a water maze. Our results confirm and extend the long-term behavioral effects of subcutaneous administration of CPF. The two treatments used produced performance decrements that suggest functional central nervous system alterations. 相似文献
6.
7.
Teng-Yi Huang Hsiao-Wen Chung Fu-Nien Wang Cheng-Wen Ko Cheng-Yu Chen 《Magnetic resonance in medicine》2004,51(2):243-247
In this work the feasibility of separating fat and water signals using the balanced steady-state free precession (SSFP) technique is demonstrated. The technique is based on the observation (Scheffler and Hennig, Magnetic Resonance in Medicine 2003;49:395-397) that at the nominal values of TE = TR/2 in SSFP imaging, phase coherence can be achieved at essentially only two orientations (0 degrees and 180 degrees ) relative to the RF pulses in the rotating frame, under the assumption of TR < T2, and independently of the SSFP angle. This property allows in-phase and out-of-phase SSFP images to be obtained by proper choices of the center frequency offset, and thus allows the Dixon subtraction method to be utilized for effective fat-water separation. The TR and frequency offset for optimal fat-water separation are derived from theories. Experimental results from healthy subjects, using a 3.0 Tesla system, show that nearly complete fat suppression can be accomplished. 相似文献
8.
连续性静脉-静脉血液滤过联合机械通气治疗ARDS的临床观察 总被引:12,自引:5,他引:7
目的 观察连续性静脉 -静脉血液滤过 (CVVH)联合机械通气治疗ARDS患者的临床疗效。方法 选择入住ICU符合ARDS诊断标准的患者 4 0例 ,随机分为 2组 :A组 2 1例 ,采用常规治疗 +机械通气 ;B组 1 9例 ,采用常规治疗 +机械通气 +CVVH。分别观察 2组患者在使用呼吸机时间、氧合指数、吸入氧浓度、动脉血氧分压、PEEP水平、心率、血压及病死率等方面的差别。结果 A、B两组患者在病因、年龄、性别、APACHEⅡ评分及平均脏器功能障碍数等方面相似 ,B组患者加用CVVH后 ,各项指标经统计学处理显示 :病死率 ,B组与A组比较 ,差异有显著性意义 (P <0 0 5 ) :其他指标与A组比较 ,差异均有高度显著性意义 (P <0 0 1 )。结论 CVVH疗法可有效清除ARDS患者血管外肺水和各种应激激素、致炎介质 ,明显改善了ARDS患者肺部氧合功能及血流动力学指标 ,提高了抢救成功率 相似文献
9.
Elemental composition and water content of myelinated axons and glial cells in rat central nervous system 总被引:1,自引:0,他引:1
The distribution of elements (e.g. Na, Cl, K) and water in CNS cells is unknown. Therefore, electron probe X-ray microanalysis (EPMA) was used to measure water content and concentrations (mmol/kg dry or wet weight) of Na, Mg, P, S, Cl, K and Ca in morphological compartments of myelinated axons and glial cells from rat optic nerve and cervical spinal cord white matter. Axons in both CNS regions exhibited similar water content ( 90%), and relatively high concentrations (wet and dry weight) of K with low Na and Ca levels. The K content of axons was related to diameter, i.e. small axons in spinal cord and optic nerve had significantly less (25–50%) K than larger diameter axons from the same CNS region. The elemental composition of spinal cord mitochondria was similar to corresponding axoplasm, whereas the water content (75%) of these organelles was substantially lower than that of axoplasm. In glial cell cytoplasm of both CNS areas, P and K (wet and dry weight) were the most abundant elements and water content was approximately 75%. CNS myelin had predominantly high P levels and the lowest water content (33–55%) of any compartment measured. The results of this study demonstrate that each morphological compartment of CNS axons and glia exhibits a characteristic elemental composition and water content which might be related to the structure and function of that neuronal region. 相似文献
10.
Alan T. Villavicencio MD Lloyd A. Hey MD Dhavalkumar Patel MD PhD Peter Bressler MD 《The Journal of allergy and clinical immunology》1997,100(6):853-854
J Allergy Clin Immunol 1997;100:853-4. 相似文献