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991.
A patient is described with type III hyperlipidaemia and primary hypothyroidism who had a unique clinical course of hyperlipidaemia. The patient was a 65-year-old man with primary hypothyroidism. His plasma total cholesterol, triglyceride and high density lipoprotein-cholesterol concentrations 1 year after starting thyroid hormone replacement therapy were 7.98, 4.04 and 0.72 mmol/l, respectively. His plasma apolipoprotein (apo) E level was 0.29 g/l and its phenotype was E2/2. Remarkably, this patient had no hyperlipidaemia before starting thyroid hormone replacement therapy but it became overt only after the hypothyroidism had been treated. Although we have not confirmed the mechanism for this, we speculate that a decrease in enzyme activities responsible for cholesterol production may have been sufficient to surpass the effect of apolipoprotein E2/2 and the decrease in enzyme activities involved in degrading and excreting plasma cholesterol, resulting in normolipidaemia.  相似文献   
992.
To explain contact failure phenomena and their development in the gas-insulated switchgear (GIS). tests were conducted by simulating abnormal current-carrying conditions using an actual 300-kV, 2000-A GIS. This paper describes the process observed. ranging from contact failures to ground faults, deteriorative phenomena and some detection methods for initial contact failure conditions. A summary of this study is as follows: (1) The contact resistances are greatly dependent on the materials and construction of contacts. (2) The relation between the initial contact resistance and the carried current resulting in arcing is derived with approximately constant Joule-heat generation. (3) Ground faults result from sagging of a shield melted by arcing or a combination of two causes: (i) scattering of molten metal caused by arcing; and (ii) sagging of a conductor caused by bolt melt down. (4) To detect initial contact failures, it is recommended to observe the contact resistance, the temperature rise on the tank surface, or the electrical partial discharges.  相似文献   
993.
994.
Evoked otoacoustic emissions (EOAEs) are considered to originate from outer hair cell movement and to be transmitted to the external auditory meatus through the ossicular chain and eardrum in a retrograde fashion. Therefore, the effect of the middle ear on EOAEs seems to be large. A sweep frequency middle-ear analyzer (MEA) has been developed that gives much more information on middle-ear dynamic characteristics than a conventional impedance meter. In this paper, applying our own EOAE measuring system and the MEA, EOAEs and middle-ear dynamic characteristics of normal subjects were measured, and an attempt was made to clarify the relationship between EOAEs and middle-ear dynamic characteristics. It is concluded that EOAEs are detected most distinctly at the middle-ear resonance frequency and that EOAEs are most detectable in normal subjects whose middle-ear mobility is moderate.  相似文献   
995.
996.
To assess the degree of noise pollution in relation to the health and safety of the employees and commuters, a study on the levels of noise originating from various locomotives and also from different other sources was undertaken at Kalupur railway station of Gujarat State in India. The sound pressure levels (SPL) were measured on platforms. Noise dose count was monitored on a ticket collector on duty for 8 h. The results reflected that the SPLs in the platforms well exceeded the day time noise exposure limit. Further, the SPLs produced by loudspeakers were high and those by train whistles were intensely high pitched. The noise dose count of the ticket collector was also in excess of ACGIH standard. All these suggest that the SPLs in the platforms can endanger the healthful living of the users. Suitable control measures have been suggested.  相似文献   
997.
998.
We report the results of our attempt to measure the proton nuclear relaxation rate, 1/T 1, in the superconducting state of the title material. The relaxation rate in the superconducting state at a field of 1 T was found much longer than that in the normal state, but it became clear that the dominant contribution came from the normal core region. The nuclear relaxation at zero field was examined by using the field cycling technique. An ln(t) term in the relaxation curve was observed at low temperatures, suggesting the contribution of the creeping motion of vortices. We discuss the possibility to determine the intrinsic temperature dependence of 1/T 1 in the superconducting state.  相似文献   
999.
An 80-year-old male with severe bullous emphysema underwent bilateral volume reduction surgery. He had suffered from dyspnea and was classified into Hugh-Jones III. In spirogram, forced vital capacity in 1 second was markedly low (0.38 l, corresponding to 19.4 % in % FEV1.0). Anesthesia was maintained by isoflurane combined with thoracic-epidural anesthesia to make extubation possible at the end of surgery. We used a critical care type ventilator (Servo 900C, Simens) for pressure controlled ventilation for fear that positive pressuse ventilation creates or aggravates airleaks. Surgery and anesthesia were performed uneventfully. We recommend lower concentration of a volatile agent combine with thoracic epidural analgesia and pressure controlled ventilation for the volume reduction surgery.  相似文献   
1000.
PURPOSE: Kainic acid (KA) has long been used in experimental animals to induce status epilepticus (SE). A mechanistic implication of this is the association between excitotoxicity and brain damage during or after SE. We evaluated KA-induced metabolic impairment and the potential mitigating effects of GYKI 52466 [1-(4-aminophenyl)-4-methyl-7,8-methylenedioxy-5H-2,3-benzodiazepine] in superfused rat cerebral cortical slices. METHODS: Interleaved [31P]/[1H] magnetic resonance spectroscopy (MRS) was used to assess energy metabolism, intracellular pH (pHi), N-acetyl-L-aspartate (NAA) level, and lactate (Lac) formation before, during, and after a 56-min exposure to 4 mM KA in freshly oxygenated artificial cerebrospinal fluid (oxy-ACSF). RESULTS: In the absence of GYKI 52466 and during the KA exposure, NAA, PCr, and ATP levels were decreased to 91.1 +/- 0.8, 62.4 +/- 3.9, and 59.1 +/- 4.3% of the control, respectively; Lac was increased to 118.2 +/- 2.1 %, and pH, was reduced from 7.27 +/- 0.02 to 7.13 +/- 0.02. During 4-h recovery with KA-free ACSF, pHi rapidly and Lac gradually recovered, NAA decreased further to 85.5 +/- 0.3%, and PCr and ATP showed little recovery. Removal of Mg2+ from ACSF during KA exposure caused a more profound Lac increase (to 147.1 +/- 4.0%) during KA exposure and a further NAA decrease (to 80.4 +/- 0.5%) during reperfusion, but did not exacerbate PCr, ATP, and pHi changes. Inclusion of 100 microM GYKI 52466 during KA exposure significantly improved energy metabolism: the PCr and ATP levels were above 76.6 +/- 2.1 and 82.0 +/- 2.9% of the control, respectively, during KA exposure and recovered to 101.4 +/- 2.4 and 95.0 +/- 2.4%, respectively, during reperfusion. NAA level remained at 99.8 +/- 0.6% during exposure and decreased only slightly at a later stage of reperfusion. CONCLUSIONS: Our finding supports the notion that KA-induced SE causes metabolic disturbance and neuronal injury mainly by overexcitation through non-N-methyl-D-aspartate (NMDA) receptor functions.  相似文献   
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