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61.
D Eidelman 《Medical hypotheses》1979,5(3):339-346
"Fatigue on Rest", headache, vertigo and the feeling of loss of balance, blurred vision, nausea, tension and irritability, were found to be prevalent amongst patients who had locally asymptomatic, unerupted impacted teeth. A comparative pressure sign was developed, which, when positive, confirmed the relationship between the impacted teeth and the medical symptoms. Removal of the impactions resulted in the alleviation of the symptoms. Stress and psychogenic factors are considered as trigger mechanisms, rather than as basic causes of the symptoms. 相似文献
62.
Valrie Kouskoff Jean-Luc Vonesch Christophe Benoist Diane Mathis 《European journal of immunology》1995,25(1):54-58
The expression of recombination activating gene (RAG) products, responsible for T cell receptor (TcR) gene rearrangement, is shut off during positive selection of thymocytes. The precise stage at which this down-regulation occurs remains somewhat controversial. We have analyzed RAG-1 expression in thymocytes of TcR transgenic mice carried on selecting versus non-selecting genetic backgrounds, both by in situ hybridization on thymus sections and by polymerase chain reaction amplification of RNA from sorted cells. The data from several transgenic lines indicate that RAG expression is already reduced in immature, cortical, CD4+CD8+ cells in the presence of positively selecting major histocompatibility complex molecules, although complete shut-off is not achieved until the mature, medullary, single-positive stage. This finding has practical and theoretical significance for studies on the mechanism of positive selection. 相似文献
63.
Summary Experiments were carried out to elucidate the mechanism that the positive inotropic effect mediated by 1-adrenoceptors is more susceptible to organic calcium antagonists than the -adrenoceptor-mediated effect. Verapamil and diltiazem displaced the specific binding of [3H]prazosin to the membrane fraction derived from the rabbit ventricular myocardium, verapamil being about 70 times more potent than diltiazem. Nifedipine did not displace the binding. While these compounds suppressed the positive inotropic effect mediated via l-adrenoceptors in 1- concentration-dependent manner, there was no correlation between the potency of the compounds to displace the [3H]prazosin binding and to inhibit the -mediated positive inotropic effect. The relative potency of three calcium antagonists to decrease the basal force of contraction and the al-mediated effect (of the same extent as compared to basal force of contraction) was consistent to each other. The positive inotropic effect mediated by -adrenoceptors was inhibited much less, and was enhanced by low concentrations of organic calcium antagonists. The differential action of calcium antagonists on the - and -mediated positive inotropic effect was mimicked by lowering the extracellular calcium concentration to 1/2, 1/4 and 1/8 of that in normal Krebs-Henseleit solution (2.5 mmol/l). These results indicate that the 1-adrenoceptor blocking activity does not play an essential role for the preferential inhibition of -mediated positive inotropic effect by organic calcium antagonists. Difference in the subcellular mechanism involved in mobilization of intracellular Ca2+ subsequent to 1-and -adrenoceptor activation may be responsible for the differential inhibitory action of calcium antagonists in the rabbit heart.
Send offprint requests to M. Endoh at the above address 相似文献
64.
目的 :探讨抗精神病药物及临床常见因素对精神分裂症患者阴、阳性症状疗效的影响。方法 :采用前瞻性设计的方法 ,对连续入院的 12 9例精神分裂症病人 ,分别在 6周的单一抗精神病药物治疗前后使用BPRS ,SANS ,SAPS及自编问卷进行调查和评估。并应用t检验和多逐步回归进行统计学分析。结果 :各量表总分治疗前后差异有显著意义 (P <0 .0 0 1) ,但SANS与SAPS各自治疗前后差值之间无显著差异 (P >0 .0 5 )。阴、阳性症状的疗效与性别和家族史的关系特别密切 (P <0 .0 5 )。结论 :性别和家族史对于精神分裂症阴、阳性症状的疗效有显著影响而抗精神病药物似乎不存在明显的优劣之分。有关发现值得进一步探讨研究。 相似文献
65.
Tohru Ozaki Toshihiko Uematsu Satoru Nagashima Masahiko Nishimoto Mitsuyoshi Nakashima 《Naunyn-Schmiedeberg's archives of pharmacology》1991,344(4):478-487
Summary DPI 201-106 (DPI), a novel and potent cardiotonic agent, exhibits its effects by prolonging the open state of Na+ channels, resulting in an increase in action potential duration, and thus, is supposed to share the class III antiarrhythmic activity. The effects of DPI on the hemodynamics, intraventricular conduction and refractoriness of heart, and the incidence of arrhythmias induced by programmed electrical ventricular stimulation (PES) were compared with (±)-dobutamine. Dogs which survived for 5 to 7 days after the induction of myocardial infarction were used as the model. The presence of sub-acute myocardial infarction caused by occluding the left anterior descending coronary artery elicited a mild left ventricular dysfunction represented by a significant decrease in peak LV dp/dt by about 20%.Both i.v. bolus injection of DPI (1, 3 and 5 mg/kg) and i. v. continuous infusion of dobutamine (3, 5 and 10 g/kg/min), which were administered in a cumulative manner, dose-dependently improved the hemodynamic parameters. At the higher doses of both DPI (3 and 5 mg/kg) and dobutamine (5 and 10 g/kg/min) the control values were reached or even exceeded. DPI dose-dependently increased the effective refractory period (ERP) of both non-infarcted and infarcted ventricular myocardia to a similar degree, but the conduction time showed a frequency-dependent increase in the infarcted myocardium to a greater degree than in the non-infarcted myocardium after DPI. In contrast, dobutamine decreased the ERP in both non-infarcted and infarcted myocardia, and slightly increased the difference of refractoriness between the non-infarcted and infarcted zones with no effect on the intraventricular conduction. In the PES study, DPI (3 and 5 mg/kg) produced a significant decrease in the incidence of ventricular tachycardia, whereas dobutamine (5 and 10 g/kg/min) tended to worsen the arrhythmias. These findings suggest that cardiotonic agents with a class III antiarrhythmic property such as DPI may be potentially useful for the management of heart failure accompanied by ischemic heart disease.Abbreviations DPI, DPI 201-106; PES
programmed electrical ventricular stimulation
- LV dp/dt
the rate of rise of left ventricular pressure
- ERP
effective refractory period
- RVOT
right ventricular outflow tract
- VT
ventricular tachycardia
- LAD
left anterior discending coronary artery
Send offprint requests to T. Uematsu at the above address 相似文献
66.
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68.
重度阻塞性睡眠呼吸暂停低通气综合征围手术期持续正压通气治疗 总被引:1,自引:0,他引:1
目的 观察重度阻塞性睡眠呼吸暂停低通气综合征 (obstructivesleepapneahypopneasyndrome ,OSAHS)围手术期病情变化和持续正压通气治疗 (continuouspositiveairwaypressure,CPAP)的影响 ,探讨围手术期治疗的必要性。方法 45例重度OSAHS患者均接受了完整保留悬雍垂的改良悬雍垂腭咽成形术。其中 2 4例不做围手术期CPAP治疗的作对照组 ,2 1例行围手术期CPAP治疗 :术前CPAP治疗 7d以上 ,于术后 1~ 3d夜应用自动调节治疗压力的CPAP(autotitratedCPAP ,AutoSet)进行治疗。治疗组患者术后第二夜在AutoSet治疗下同时做多导睡眠监测 (polysomnography,PSG)。对呼吸暂停低通气指数 (apneahyponeaindex ,AHI)、最低血氧饱和度 (lowestSaO2 ,LSaO2 )、血压以及睡眠结构等指标进行观察。结果 对照组 2 4例患者中有 6例于术后第二夜LSaO2 比术前下降 ,AHI升高 ,另外 1 8例患者LSaO2 升高 ,AHI下降。治疗组 2 1例患者CPAP治疗前AHI为 (61 1± 9 9)次 /h( x±s,以下同 ) ,LSaO2 为 65 0 %± 9 6 % ,手术前CPAP治疗后AHI为 (2 2± 1 4)次 /h ,LSaO2 为 94 5 %± 2 9% ,t检验P <0 0 0 1 ;手术前经CPAP治疗临床症状消失。术后患者均能良好耐受AutoSet治疗 ,术后第二夜应用AutoSet治疗时AHI为 (3 6± 1 8)次 /h 相似文献
69.
70.
建筑工地外来务工人员心理卫生状况调查 总被引:9,自引:1,他引:9
目的 :了解建筑工地外来务工人员的心理卫生状况 ,为预防心理疾病 ,增进身心健康提供依据。方法 :采用症状自评量表 (SCL - 90 )对建筑工地外来务工人员 5 18人的心理卫生状况进行评价。结果 :9个因子分与中国常模比较差异均有显著性 (P<0 .0 1) ,且各年龄组与中国常模比较差异也有显著性 ,均低于常模 ;各因子分在不同年岭 ,不同文化的建筑工地外来务工人员间比较差异无显著性。研究还发现做事“必须反复检查”、“必须反复洗手、点数目或触摸某些东西”、“做事必须做得很慢以保证做得正确”等强迫症状是建筑工地外来务工人员中较常见的阳性项目。结论 :建筑工地外来务工人员强迫症状发生频率较其它症状高 ,应加强其心理卫生教育 相似文献