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241.
用常规心电图及动态心电图监测的方法,分别观察30例糖尿病人和30例非糖尿病人无症状心肌缺血的发生率。发现无症状心肌缺血在糖尿病组显著高于非糖尿病组(P〈0.05),部分糖尿病人有严重心肌缺血却无胸痛症状,可能与其植物神经功能损害引起痛阈提高、血中内啡肽水平增高导致痛觉敏感性下降有关,用动态心电图监测可提高无症状心肌缺血的检出率。 相似文献
242.
目的 观察拜新同 (长效 )及艾克地平 (中效 )两种钙拮抗剂对高血压患者血压变异性的影响。方法 79例原发性高血压分为 3组 :未用药组 ;拜新同组 (30mg每日 1次口服 ) ;艾克地平组 (2 0mg每日 2次口服 )。用药的第7d做动态血压监测 ,观察血压变异性。结果 与未用药组比较 :艾克地平组血压变异性改变不显著 (P >0 .0 5 ) ;拜新同组的收缩压变异性下降 (P <0 .0 5 ) ,舒张压变异性改变不明显 (P >0 .0 5 )。结论 拜新同可降低原发性高血压患者的收缩压变异性 ,艾克地平不改变血压变异性。 相似文献
243.
CHM. SAMAMA R. QUEZADA B. RIOU E. MOURGEON M. AROCK A. ANKRI P. VIARS 《Acta anaesthesiologica Scandinavica》1994,38(3):232-237
A prospective study was conducted to evaluate a new compact portable coagulation monitor (Ciba–Corning Biotrack 512 Monitor), which enables the clinician to perform instantaneous activated partial thromboplastin time (APTT) and prothrombin time (PT). 126 patients scheduled for heparinized and nonheparinized vascular surgery, and gynaecological surgery, were included. A drop of capillary or venous whole blood was applied in disposable cartridges to successively perform APTT and PT, and the results of the tests were compared with conventional laboratory methods, performed in two different laboratories (Lab. A and B). Comparisons between Lab. A. and Lab. B. enables determination of the bias, precision, and percent of outliers (patients whose values differed more than 20%) in conventional methods. The reference value was defined as the mean of Lab. A. and Lab. B. values. For PT, there were no statistical differences between the capillary and venous samples performed with the portable monitor, and the reference value, for the bias, the precision and the proportion of outliers. For APTT, there were no statistical differences between the capillary and venous samples performed with the portable monitor, and the reference value, for the bias and the precision. The percent of outliers, however, was significantly greater with the venous sample of the compact monitor than with the reference (48 versus 22%), and even if it did not reach the statistical significance ( P = 0.07) it was also higher with the capillary sample performed with the Ciba Monitor than with the reference (33%). In conclusion the assessment of blood coagulation using this new compact monitor could be of major interest during the intraoperative period when immediate results are mandatory, even if PT is more accurate than APTT with this new method. 相似文献
244.
245.
顺铂对结直肠癌肿瘤浸润淋巴细胞杀伤活性的影响 总被引:1,自引:0,他引:1
为在临床选择有效的免疫化疗方案提供一定的理论依据,作者以结直肠癌肿瘤浸润淋巴细胞(TIL)和顺铂(CDDP)为研究对象,对16名手术治疗的结直肠癌患者,分别观察CDDP体内注射及体外预处理TIL和Raji细胞对TIL表面标志和杀伤活性的影响。流式细胞仪检测结果显示,静脉注射CDDP能增加结直肠癌TIL中CD3+/CD4+和CD3+/CD8+细胞含量,同时增强TIL体外杀伤Raji细胞的活性;而体外以CDDP处理Raji细胞能增强其对结直肠癌TIL杀伤的敏感性。作者认为,对于联合应用TIL和CDDP治疗结直肠癌的临床效果有必要进一步研究。 相似文献
246.
247.
Topographical analysis of the EEG effects of a subconvulsive dose of lidocaine in healthy volunteers
O. DETSCH U. ERKENS U. JACOFSKY A. THIEL E. KOCHS G. HEMPELMANN 《Acta anaesthesiologica Scandinavica》1997,41(8):1039-1046
Background: The purpose of the present study was to assess the effects of intravenous lidocaine on spatial changes of electroen-cephalographic power and on psychomotoric status in conscious volunteers.
Methods: In 11 healthy volunteers lidocaine (2-min bolus, 100 mg; 15-min infusion, 40 μg kg-1 min-1 ) or placebo were given intravenously in a randomized, single-blinded, two-way crossover study. Haemodynamics and lidocaine plasma concentrations were measured at baseline and within a period of 30 min following bolus injection. Vigilance and emotional status were tested using visual analogue scales (VAS). Toxic CNS effects were evaluated by a questionnaire. The raw EEG (17 leads, reference Cz ) and computed power spectra were continuously recorded.
Results: The chosen lidocaine dosage led to nearly constant plasma concentrations (unbound lidocaine 2.5 min and 15 min after bolus 0.36±0.14 μg/ml and 0.30±0.06 μg/ml, respectively [mean±SD]). The placebo caused no symptoms, changes in VAS-scores or EEG-parameters. Lidocaine induced pronounced subjective symptoms and significant increases in delta activity for 15 min, most dominant at the frontotemporal and occipital leads (max. +219% O1 ). Frontal and occipital beta1 and beta2 power (max. +131% and +124% at O1 , respectively) was immediately increased after the bolus injection. No EEG changes occurred at central region Cz , and no interhemispheric EEG differences were noted. Theta, alphal, and alpha2 power remained unchanged.
Conclusion: The current data demonstrate simultaneous changes in psychomotoric status as well as delta and beta spectral power during lidocaine infusion. These data could be an indication that the pronounced frontotemporal and occipital EEG changes are the electroencephalographic expression of subjective sensations. 相似文献
Methods: In 11 healthy volunteers lidocaine (2-min bolus, 100 mg; 15-min infusion, 40 μg kg
Results: The chosen lidocaine dosage led to nearly constant plasma concentrations (unbound lidocaine 2.5 min and 15 min after bolus 0.36±0.14 μg/ml and 0.30±0.06 μg/ml, respectively [mean±SD]). The placebo caused no symptoms, changes in VAS-scores or EEG-parameters. Lidocaine induced pronounced subjective symptoms and significant increases in delta activity for 15 min, most dominant at the frontotemporal and occipital leads (max. +219% O
Conclusion: The current data demonstrate simultaneous changes in psychomotoric status as well as delta and beta spectral power during lidocaine infusion. These data could be an indication that the pronounced frontotemporal and occipital EEG changes are the electroencephalographic expression of subjective sensations. 相似文献
248.
J. D. Kakisis F. Abir C. D. Liapis B. E. Sumpio 《European journal of vascular and endovascular surgery》2003,25(6):493-504
OBJECTIVES: to summarize existing evidence regarding the benefits and the risks of all available interventional and medical means aimed at cardiac risk reduction in patients undergoing vascular surgery. DESIGN: review of the literature. MATERIALS AND METHODS: a critical review of all studies examining the impact of various prophylactic cardiac maneuvers on perioperative outcome following vascular surgery was performed. Overall mortality, cardiac mortality and myocardial infarction rate were used as the outcome measures. RESULTS: coronary artery bypass grafting is associated with a 60% decrease in perioperative mortality in patients undergoing vascular surgery, but in most of the cases this decrease does not outweigh the combined risk of the cardiac and the subsequent noncardiac vascular procedure. Data supporting the cardioprotective effect of percutaneous transluminal angioplasty in the perioperative setting are insufficient. beta-blockade has been shown to decrease perioperative mortality and cardiac morbidity in both high-risk (strong evidence) and low-risk (weak evidence) patients. CONCLUSIONS: coronary revascularization is rarely indicated to simply get the patient through vascular surgery and should be reserved for patients who would need it irrespective of the scheduled vascular procedure. Among all available pharmacological agents, including beta-blockers, alpha-agonists, calcium channel blockers and nitrates, only beta-blockers have been proven to reduce the cardiac risk of vascular surgery. 相似文献
249.
Acute toxicity of two pyrethroids,permethrin, and cypermethrin in neonatal and adult rats 总被引:2,自引:0,他引:2
Franco Cantalamessa 《Archives of toxicology》1993,67(7):510-513
The present study aims specifically at obtaining a comparison of the acute toxicity of cypermethrin (CY), a type I pyrethroid, and permethrin (PERM), a type II pyrethroid, administered orally as a single dose to neonatal and adult rats, and at assessing the importance of pyrethroid biotransformation in CY and PERM toxicity through use of drug metabolism inhibitors. Our experiments show that CY is more toxic than PERM to adult and neonatal rats. The sensitivity of neonatal rats both to CY and to PERM toxicity is higher, the younger the animals. CY is much more toxic than PERM in the neonatal rat, compared with the adult. In rats aged 8, 16, and 21 days, pretreatment with piperonil butoxide (PB), a monooxygenase inhibitor, or with tri-o-tolyl phosphate (TOTP), an esterase inhibitor, does not produce significant variations in the lethal effects of CY and PERM. Instead, in the adult rats, a significant increase in CY (X2=5.97;p<0.05) and PERM (X2=4.37;p<0.05) mortality occurred in rats pretreated with esterase inhibitors, whereas no increase in CY and PERM toxicity was found in adult animals pretreated with monooxygenase inhibitor. It was concluded that the higher level of sensitivity of the neonate rat to pyrethroid toxicity is probably due to incomplete development of the enzymes which catalyze the metabolism of pyrethroids in the liver of young animals. It is suggested that ester hydrolysis is an important pyrethroids detoxification reaction in the adult rat. 相似文献
250.
Jan Sollenberg Rasmus Bjurström Kent Wrangskog Olof Vesterberg 《International archives of occupational and environmental health》1988,60(5):365-370
Summary Styrene exposure of 18 workers in fiber-glass reinforced plastic industries was measured for 30-min periods throughout each workday for a week. The styrene uptake was estimated using pulmonary ventilation measurements. All urine voidings were collected separately and the styrene metabolites, mandelic acid (MA) and phenylglyoxylic acid (PGA) were determined. The relationship between both exposure and uptake versus excretion of these metabolites was studied. Styrene metabolite concentrations and excretion rates (with 95% tolerance limits) were calculated to correspond to a constant 8-h exposure at the Swedish exposure limit level (25 ppm) or an uptake of an exposure limit related styrene dose (6.3 mmol). The tightest tolerance limits were obtained for excretion rate of MA + PGA per 24 h. The calculated biological exposure limit was 3.4 (± 0.7) mmol MA + PGA/24 h for a dose of 6.3 mmol styrene. 相似文献