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21.
环氧氯丙烷具有升高血糖作用。血糖升高有良好的剂量效应关系和时间效应关系。血糖达峰值后恢复10%,50%,90%的效应与持续时间曲线斜率随剂量增加而递减,提示环氧氯丙烷在体内消除和转运具有多房室模型特性,血糖达峰值持续时间较长。说明环氯氧丙烷升高血糖作用部位在周边室。环氧氯丙烷引起肾上腺皮质束状带细胞光面内质网增多和脂滴增加,髓质肾上腺素细胞分泌颗粒增多和高尔基复合体发达。说明环氧氯丙烷作用于肾上腺皮质束状带细胞,引起糖皮质激素增加,诱导髓质肾上腺素细胞内PNMT增加和活性增强,促使肾上腺素增多,导致血糖升高。  相似文献   
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目的 调查贵州省江口土家族男性葡萄糖-6-磷酸脱氢酶(G6PD)缺陷症的基因频率。方法 2002年10-11月随机选取227名江口当地土家族男性居民,采用四氮唑蓝(NBT)纸片定性法初筛G6PD缺陷症。G6PD/6PGD比值法定量确诊。结果 对贵州省江口县227名土家族男性进行筛查,共检出17例G6PD缺陷阳性。其基因频率为0.0749。结论 通过对贵州土家族G6PD缺乏症基因频率的调查和分析,初步了解了贵州省土家族G6PD缺乏症的分布特征。为该地区预防该疾病、指导临床、提高少数民族的素质及研究该民族起源提供了一定的依据。  相似文献   
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Summary Pefloxacin was applied to a newborn suffering from ventriculitis caused byKlebsiella pneumoniae after failure of routine antibiotics. Treatment was successful. Blood and CSF levels were high, thus documenting good CSF penetration. In addition to this case report, a review of the literature regarding seven neonates with CNS infection treated with fluoroquinolones and from whom CSF levels were obtained, is presented. In conclusion, due to their excellent activity against gram-negative microorganisms, fluoroquinolones may be considered in the treatment of neonatal CNS infections if the pathogen is resistant to routinely used antibiotics. Only limited experience is available with fluoroquinolones in pediatric patients given their potential for cartilage toxicity in young animals.
Ventrikulitis durchKlebsiella pneumoniae bei einem Neugeborenen. Erfolgreiche Behandlung mit Pefloxacin
Zusammenfassung Nach Versagen von Routineantibiotika wurde Pefloxacin eingesetzt, um eine durchKlebsiella pneumoniae verursachte Ventrikulitis bei einem Neugeborenen zu behandeln. Die Therapie war erfolgreich. Im Blut und im Liquor cerebrospinalis fanden sich hohe Spiegel von Pefloxacin. Die hohe Penetrationsrate von Pefloxacin in den Liquor ist damit dokumentiert. In einer Literaturübersicht werden sieben weitere Fälle von ZNS-Infektionen bei Neugeborenen dargestellt, die unter Bestimmung der Liquorspiegel mit Fluorochinolonen behandelt wurden. Fluorochinolone kommen wegen ihrer hohen Aktivität gegen gramnegative Bakterien für die Behandlung einer gegen herkömmliche Antibiotika resistenten gramnegativen ZNS-Infektion bei Neugeborenen in Frage. Die Erfahrungen mit Fluorochinolonen sind bei pädiatrischen Patienten jedoch wegen der Möglichkeit einer bei jungen Tieren beobachteten Knorpelschädigung begrenzt.
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Seventy-four patients recovering from acute myocardial infarction underwent right atrial pacing before hospital discharge, and treadmill exercise testing 6 months later. The early right atrial pacing test was positive in 32 patients (43 percent) and the late treadmill test was positive in 32 patients (42 percent). The results of the two tests were concordant in 77 percent of the patients, 23 with an ischemic response and 34 with a normal response on both tests. In nine patients a positive right atrial pacing test was followed by a negative treadmill test, and in eight patients a negative pacing test was followed by a positive treadmill test. A positive right atrial pacing test at hospital discharge had an 81.0 percent predictive accuracy for a positive late treadmill test; chest pain, congestive heart failure or increased cardiothoracic ratio at discharge had a predictive value of only 52.9, 42.8 and 42.8 percent, respectively. Both the early right atrial pacing test and the late treadmill test were positive in a significantly higher proportion of patients with inferior or subendocardial infarction than of patients with anterior myocardial infarction. During early right atrial pacing the mean maximal heart rate achieved was higher than that during late treadmill testing (148 versus 133 beats/min) and the mean systolic blood pressure was lower (137 versus 162 mm Hg), but the pressure-rate product was similar on the two tests (20,282 versus 21,455 mm Hg/min). This finding may explain the similar frequency of ischemic responses to the two tests. These results indicate that the response to right atrial pacing soon after myocardial infarction is a good predictor for the presence or absence of an ischemic response to treadmill testing 6 months later. Thus, early right atrial pacing at the time of hospital discharge may be used to determine the pace of rehabilitation and short-term prognosis.  相似文献   
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Cardiac performance and mitral regurgitation were measured by Doppler echocardiography and right heart catheterization in 12 patients with severe congestive heart failure who performed isometric exercise during control and intravenous administration of dobutamine and nitroglycerin. During control isometric exercise, mitral regurgitant volume increased from 18 +/- 13 to 31 +/- 17 ml (p less than 0.01), while forward stroke volume, by both thermodilution and Doppler echocardiography, substantially decreased. At rest, dobutamine decreased mitral regurgitant volume from 18 +/- 13 to 11 +/- 10 ml (p less than 0.05), while forward stroke volume increased from 46 +/- 13 to 55 +/- 15 ml (p less than 0.05). During isometric exercise, dobutamine tended to decrease mitral regurgitant volume (24 +/- 12 vs. 31 +/- 17 ml; NS) when compared with control exercise. At rest, nitroglycerin decreased mitral regurgitant volume from 18 +/- 13 to 11 +/- 11 ml (p less than 0.05), while forward stroke volume, by both thermodilution and Doppler echocardiography, substantially increased. Similarly, during isometric exercise, nitroglycerin decreased mitral regurgitant volume from 31 +/- 17 to 20 +/- 14 ml (p less than 0.05), while significantly increasing forward stroke volume. At control rest, the median mitral regurgitant fraction was 24% for the 12 patients. Neither dobutamine nor nitroglycerin changed significantly forward stroke and mitral regurgitant volumes at rest and during isometric exercise in the six patients with resting mitral regurgitant fraction below the median. In contrast, dobutamine and nitroglycerin significantly decreased mitral regurgitant volume and increased forward stroke volume both at rest and during isometric exercise in the six patients with mitral regurgitant fraction greater than the median.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
29.
Here we aim to evaluate the ability of transcranial direct current stimulation (tDCS), which is applied over Wernicke’s area and its right homologue, to influence lexical decisions and semantic priming and establish an involvement for temporo-parietal areas in lexical and semantic processing. Thirty-two subjects (17 women) completed a lexical decision task and a semantic priming task while receiving 20 min of bilateral tDCS stimulation (right anodal/left cathodal or left anodal/right cathodal stimulation) or sham stimulation. We hypothesized that right anodal/left cathodal stimulation over temporo-parietal areas would selectively interrupt the typical lexical processing dominance of the left hemisphere and facilitate mediated priming, while left anodal/right cathodal stimulation would selectively facilitate lexical processing and direct priming. Results showed impaired lexical processing under right anodal/left cathodal stimulation in comparison with sham and left anodal/right cathodal stimulation. Results are discussed in light of previous findings and hemispheric lateralization models.  相似文献   
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