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21.
FUMIHIKO YASUMA md HIROSHI HAYASHI md KAORU SHIMOKATA md MITSUHIRO YOKOTA md TAMOTSU OKADA md JUNZOH KITOH p hd 《Psychiatry and clinical neurosciences》1997,51(4):237-239
Abstract Although respiration in trained canines is well investigated, the process of preparing dogs has not been described in any great detail. Moreover, their daytime patterns of sleep and wakefulness during 1 or 2 h of electroencephalogram (EEG) and electrocardiogram (ECG) recordings are not clear. Therefore, we describe the process of selecting and training dogs, in which we recorded EEG and ECG in the laboratory. First, 14 of 1242 dogs dealt with over a 1 year period were chosen. They were trained for 2 h to lie quietly and to sleep in the laboratory; this training procedure was repeated 152 times. Three dogs were then selected and a permanent tracheostomy was performed in one. Finally, EEG and ECG were recorded with the bipolar fine needle electrodes; respiration was recorded simultaneously through a tube inserted to a tracheostomy in one dog. Wakefulness, slow wave sleep (SWS) and rapid eye movement (REM) sleep (REMS) were identified according to the EEG pattern and on the basis of the behavioral criteria. Recordings were performed 12 or 13 times in each dog. Complete sleep cycles, including wakefulness, SWS and REMS in this sequence, were observed 3.9–4.1 times. The mean duration of SWS was 2.2–4.4 min and that of REMS was 3.5–4.6 min. The REMS latency was 33.9–41.8 min. Fluctuation of heart rate with respiration, termed respiratory sinus arrhythmia, was noted in the ECG. Heart beat increased with inspiration and decreased with expiration. The present study demonstrates how to select and train sleeping dogs and shows their undisturbed daytime sleep and wakefulness patterns. 相似文献
22.
James R. Trudell Wei-Qi Lin Dale A. Chrystof Gary Kirshenbaum C. Murray Ardies 《Alcoholism, clinical and experimental research》1995,19(3):753-758
Ethanol-induced fatty liver in rats was attenuated by repeated running exercise, and the protective effect of exercise was associated with the synergistic expression of heat shock proteins (HSP72). Rats were placed in four groups of six. The two ethanol-fed groups of rats received a liquid diet (Lieber-DeCarli formulation) in which 36% of the calories were derived from ethanol. One group remained sedentary (S/E), whereas the other was trained to run on a rodent treadmill at a speed of 27 m/min, 1 hr/day, 5 days/week, for 7 weeks (R/E). Two other groups–one exercised as previously mentioned (R/C) and one sedentary (S/C)–received control-liquid diets in which the ethanol was isocalorically substituted with a dextran/maltose mixture. The degree of fatty infiltration in liver sections stained with hematoxylin and eosin was graded on a 0–4 scale and the data analyzed by ANOVA on ranks. Ethanol significantly induced fatty infiltration in the S/E group, whereas fatty infiltration in the livers of the R/E group was not different from the S/C group. Electrophoresis and Western blotting of liver homogenates demonstrated that HSP72 was not expressed in either the S/C or S/E groups and was only slightly expressed in the R/C group. The combination of exercise and ethanol, however, resulted in an elevated expression of HSP72 in the R/E group. The content of HSP73 was unaffected by any treatment. 相似文献
23.
本文报道1988年6月~11月,单独应用上海交通大学电力工程系研制的JT—ESWL—Ⅱ型体外震波碎石机,治疗尿路结石506例,其中肾结石304例(双侧12例)输尿管结石199例(双侧5例),膀胱结石3例。冲击能量15~40焦耳,每次治疗冲击波次数为400~2800次。本组无开放手术、无肾脏丧失、无死亡。效果满意者96.44%。其并发症主要有血尿、结石串。作者认为单用ESWL治疗小于3Cm的尿路结石安全可靠、无严重并发症。文中对单用体外震波碎石(ESWL)治疗尿路结石病例选择,如何减少并发症,提高治疗效果进行了讨论。 相似文献
24.
热休克反应对大鼠感染性脑水肿脑组织诱生型一氧化氮合酶mRNA表达的影响 总被引:1,自引:0,他引:1
:探讨热休克反应 (HSR)对百日咳杆菌所致的大鼠感染性脑水肿诱生型一氧化氮合酶 (iNOS)mRNA表达的影响。方法 :从大鼠左侧颈内动脉注入百日咳菌液制备感染性脑水肿 (感脑 )模型 ,采用组织细胞原位杂交技术检测脑组织iNOSmRNA的表达。结果 :生理盐水组、4h感脑组及 4h热休克处理组均未见iNOSmRNA表达 ,8h ,2 4h时感染性脑水肿组均有明显的杂交信号 ,以 2 4h更为明显 ;而 8h ,2 4h热休克处理组仅有少数细胞有阳性信号。结论 :热休克反应对感染性脑水肿的保护作用可能与抑制iNOSmRNA的表达有关 相似文献
25.
G. Dewasmes B. Bothorel A. Hoeft V. Candas 《European journal of applied physiology》1993,66(6):542-546
Summary Thermoregulatory sweating [total body (m
sw,b), chest (m
sw,c) and thigh (m
sw,t) sweating], body temperatures [oesophageal (T
oes) and mean skin temperature (T
sk)] and heart rate were investigated in five sleep-deprived subjects (kept awake for 27 h) while exercising on a cycle (45 min at approximately 50% maximal oxygen consumption) in moderate heat (T
air andT
wall at 35° C. Them
sw,c andm
sw,t were measured under local thermal clamp (T
sk,1), set at 35.5° C. After sleep deprivation, neither the levels of body temperatures (T
oes,T
sk) nor the levels ofm
sw, b,m
sw, c orm
sw, t differed from control at rest or during exercise steady state. During the transient phase of exercise (whenT
sk andT
sk,1 were unvarying), them
sw, c andm
sw, t changes were positively correlated with those ofT
oes. The slopes of them
sw, c versusT
oes, orm
sw, t versusT
oes relationships remained unchanged between control and sleep-loss experiments. Thus the slopes of the local sweating versusT
oes, relationships (m
sw, c andm
sw, t sweating data pooled which reached 1.05 (SEM 0.14) mg·cm–2·min–1°C–1 and 1.14 (SEM 0.18) mg·cm–2·min–1·°C–1 before and after sleep deprivation) respectively did not differ. However, in our experiment, sleep deprivation significantly increased theT
oes threshold for the onset of bothm
sw, c andm
sw, t (+0.3° C,P<0.001). From our investigations it would seem that the delayed core temperature for sweating onset in sleep-deprived humans, while exercising moderately in the heat, is likely to have been due to alterations occurring at the central level. 相似文献
26.
The pharmacokinetics and haemodynamic effects of isosorbide dinitrate (ISDN) have been investigated following administration of single doses as a sublingual (SL) spray (2.5 mg), sublingual tablet (5 mg) and peroral tablet (10 mg) in a randomised, placebo-controlled double-blind cross-over trial in 16 healthy volunteers.After the sublingual spray Cmax was higher (39.0 ng·ml-1) and tmax was shorter (3.9 min) than after the sublingual (22.8 ng·ml-1 and 13.8 min) and peroral (16.9 ng·ml-1 and 25.6 min) tablets. The AUC of ISDN did not differ following any of the three formulations (1031; 879; 997 ng·ml-1·min, for the spray, SL tablet and PO-tablet, respectively). Mononitrate metabolites of ISDN (IS-2-MN and IS-5-MN) and total nitrates in plasma increased in proportion to the administered dose. This indicates that the fraction of the dose absorbed was the same for all the formulations but that the extent of first-pass metabolism increased in the order sublingual spray < sublingual tablet < peroral tablet. Thus, compared to the spray, the relative bioavailability of ISDN was 48% and 28% from the sublingual and peroral tablets, respectively.The haemodynamic effects were quantified using the a/b ratio of the finger pulse wave and the systolic blood pressure and heart rate under orthostatic conditions. For the a/b ratio of the finger pulse, the maximal effect was higher (emax=130%) and the time to emax (temax) shorter (16.6 min) after the spray than the sublingual tablet (84.4% and 25.5 min) or peroral tablet (90.2 and 31.3 min). The onset of effect was within 3, 5 and 7.5 min after the spray, sublingual and peroral tablets, respectively. A larger change in the orthostatically-induced decrease in systolic blood pressure and increase in heart rate was obtained following peroral than sublingual administration despite the similar plasma concentrations of ISDN. This probably reflects the larger amount of pharmacodynamically active mononitrate metabolites formed after oral dosing. The integrated effect following administration of 2.5 mg ISDN as spray was similar to that of a sublingual tablet of 5 mg. 相似文献
27.
彩色多普勒在心脏起搏器综合征诊断中的应用价值 总被引:1,自引:1,他引:0
目的 :探讨运用彩色多普勒血流显像 (CDFI)并结合心电图 (ECG)诊断起搏器综合征 (PMS)的临床价值。方法 :对具有详实临床及ECG资料的心室按需 (VVI)起搏器安置患者 6 0例及对照组 4 8例进行CDEI检查 ,观察起搏组与对照组的三尖瓣返流 (TR)的发生率、返流程度 ,并分析二者之间的相关性。结果 :起搏组出现逆传P波 (即PMS阳性 )者 15例 ,CDFI检测出现TR者 2 0例 ,明显高于对照组 ,且PMS阳性者TR发生率明显高于PMS阴性者 ,表明安置VVI起搏器后出现逆传P波与TR的发生相关性良好。结论 :CDFI对PMS的诊断具有重要意义 ,尤其将ECG与CDFI结合应用有助于诊断率的提高。 相似文献
28.
膜表达热休克蛋白70真核表达载体的构建及其对肿瘤细胞的转染 总被引:2,自引:0,他引:2
目的构建普遍适合性的膜表达热休克蛋白70(HSP70)的真核表达载体,修饰并建立HSP 70表达并结合在细胞膜表面的肿瘤细胞.方法RT-PCR法从人胚肾中获取HSP 70的cDNA,扩增成带酶切位点的目的基因.选择载体pDisplay,将目的基因插入载体多克隆酶位点中.DNA测序证实后,以脂质体转染的方法,将载体转染到黑色素瘤细胞.用G418抗性筛选获得阳性克隆.结果酶切电泳和DNA测序证实载体构建正确;目的基因的上游带信号肽序列,下游带跨膜序列.RT-PCR产物电泳、Westem Blotting、激光共聚焦显微镜和流式细胞术证实大量HSP 70表达并结合在转染的黑色素瘤细胞膜表面.结论成功地构建了膜表达HSP 70的真核表达载体;转染到黑色素瘤细胞后,细胞膜表面表达丰富的HSP70.转染细胞可以进一步制备新型瘤苗. 相似文献
29.
超声波在医疗领域中的应用及分析例举 总被引:1,自引:0,他引:1
本文简要介绍了超声波的三个特点,并从诊断、治疗、辅助用途三方面论述了超声波在临床的普遍应用,其中重点介绍了三维超声成像技术。 相似文献
30.
目的研究脊髓损伤后热休克蛋白27(HSP27)、表皮脂肪酸结合蛋白(FABPs)和金属蛋白酶组织抑制因子-1(TIMP-1)的基因表达及甲基强的松龙(MP)对其表达的影响.方法SD大鼠30只.随机分为假手术组、单纯脊髓损伤组(损伤组)及脊髓损伤+大剂量MP治疗组(MP组),每组10只.应用改良的Allen's打击法致T8脊髓损伤.MP组大鼠伤后即刻从尾静脉内注射大剂量MP(30mg/kg).损伤后24h切取损伤平面上下0.5cm的脊髓组织,进行RT-PCR反应,检测HSP27、FABPs和TIMP-1的基因表达.结果术后24h假手术组HSP27、FABPs和TIMP-1的基因表达相对丰度分别为0.0643±0.0152、0.6413±0.1005和0.7091±0.0577;损伤组上述三个因子的表达升高,分别为1.0013±0.3861、1.2187±0.2851和0.8971±0.1092,与假手术组比较差异有显著性(P<0.01、P<0.05、P<0.05);MP组上述三个因子的表达继续升高,分别为1.2858±0.1384、1.7122±0.1766和1.2081±0.1093,与损伤组比较差异有显著性(P<0.05、P<0.01和P<0.01).结论脊髓损伤后,邻近损伤处的脊髓组织中HSP27、FABPs及TIMP-1的基因表达显著增高,大剂量MP能进一步促进三个因子表达,发挥组织保护作用. 相似文献