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1.
背景:Sauvegrain方法是通过分析肘部X线片来评估骨龄,常用于青春期生长发育最为迅速的两年间的骨龄测定。本文旨在研究该方法的准确性以及在小儿骨科中的应用价值。 方法:Sauvegrmn法主要评估肘部的4个解剖标志点:外髁、肱骨滑车、尺骨鹰嘴突以及桡骨近端骨骺。它是一个27分制的评分系统。对上述结构所得的评分进行合计而得出一个总分,然后使用标准图表确定骨龄。让三位观察者分别利用该方法进行骨龄评估。三位观察者通过分析60个男孩和60个女孩样本左肘部的前后位和侧位X线片来测定骨龄,并将该结果与通过分析左手和腕部后前位X线片的Greulich和Pyle图谱而得出的骨龄结果进行比较。间隔4周后每个观察者再测定骨龄一次。 结果:通过分析肘部X线片的方法测定骨龄更为精确,因为采用该方法测定骨龄可以精确到半岁。根据观察者的评定,Sauvegrain法显示出很好的观察者之间的相关性(r=0.93)和可重复性(r=0.96)。Sauvegrain法与Greulich和Pyle图谱之间有很好的相关性(r=0.85)。然而,一些肘部生长中心显示出一种中间的发育形态,这种形态学不适合Sauvegrain法的评分。这就导致了数据分析时出现误差。我们建议对于这些样本设定中间评分,并且通过修改原始图表而使评分更为精确。 结论:改良的Sauvegrain法简单、可靠而且可重复性高,它补充了Greulich和Pyle图谱的不足。在临床实践中,骨骼成熟度可以通过骨龄、年生长率以及第二性征而得以很准确的评估。因此,当青春期需要进行骨骺或脊柱关节融合术时,这种方法对于确定手术时间具有重要意义。 可信水平:诊断性研究,Ⅱ级,进一步可信度参见作者介绍。  相似文献   
2.
The haemodynamic effects of nitrovasodilators and their mechanisms of action on portal hypertension remain unclear. The splanchnic and systemic haemodynamic response to the infusion of isosorbide dinitrate (100 μg/kg per min), a nitrovasodilator, was investigated in cirrhotic rats. The role of the conscious state in the haemodynamic response to isosorbide dinitrate was examined using rats that were anaesthetized with pentobarbitone. The role of sympathetic tone in the haemodynamic response to isosorbide dinitrate was examined using rats pretreated with the ganglion blocker hexamethonium. Isosorbide dinitrate had no haemodynamic effects in conscious, unblocked normal and cirrhotic rats. Isosorbide dinitrate had no haemodynamic effects in normal and cirrhotic rats treated with hexamethonium. In normal anaesthetized rats, isosorbide dinitrate significantly decreased systemic vascular resistance (414±25 vs 290±26 dyn.s/cm5 per 100 g). In cirrhotic anaesthetized rats, isosorbide dinitrate significantly decreased mean arterial pressure (98±6 vs 79±7 mmHg), systemic vascular resistance (318±30 vs 207±10 dyn.s/cm5 per 100 g), portal pressure (14.0±1.0 vs 11.3±0.9 mmHg) and portal territory vascular resistance (1362±163 vs 1031±182 dyn.s/cm5 per 100 g). In conclusion, this study shows that the portal hypotensive effects of isosorbide dinitrate depend upon the alterations of vascular tone by pentobarbitone.  相似文献   
3.
Chronic alcoholization by alcohol inhalation was used to studythe properties of magnesium, a non-competitive NMDA receptorantagonist, and CGP 39551, a competitive NMDA receptor antagonist,on behavioural dependence as estimated by the free-choice paradigm[alcohol 10% (v/v) vs. water], on the hypermotility after alcoholwithdrawal, and finally on the cortical vascularization. Thefirst experimental group received the drugs per os during thewhole alcoholization period. Magnesium (20 mg/kg/day) decreasedthe alcohol dependence while CGP 39551 (5 and 10 mg/kg/day)increased, in a dose-dependent manner, the dependence to alcohol.A second group of animals received the same drugs at the samedosages, not simultaneously during chronic alcoholization, butimmediately after alcoholization in one shot i.p. injection.In this case, rats receiving 5 mg/kg CGP 39551 never showedany dependence towards alcohol, while 10 mg/kg CGP 39551 or20 mg/kg magnesium prolonged the number of days of alcohol dependence.These results thus indicate the close interaction between NMDAreceptor function and dependence for alcohol. Magnesium hadno effects on hypermotility, while CGP 39551-treated animalspresented a decrease in the hypermotility observed after alcoholwithdrawal. Neither drug affected the hypervasculanzation accompanyingthe chronic alcoholization.  相似文献   
4.
Aprikalim is a potent, specific, and selective opener of ATP-sensitiveK+ (KATP) channels. By virtue of this pharmacological property,aprikalim affords cardioprotection in experimental models ofischemia/reperfusion injury, and, at higher doses, also causesperipheral or coronary vasodilatation. Direct-acting peripheralvasodilators can cause myocardial lesions, particularly in ratsand dogs. However, unexpectedly, aprikalim produced this effectalso in monkeys. Thus, the primary aim of this investigationwas to assess whether in monkeys these myocardial lesions werethe direct or indirect consequence of the vascular effects ofaprikalim. Cyno-mologus monkeys were given the ß-adrenoceptorantagonist nado-lol (2 mg/kg po, twice daily) for 4 consecutivedays. On the third and fourth day of the experiment, they receivedaprikalim (1 mg/kg po). In another series, two monkeys carryingtelemetry transmitters for blood pressure and heart rate measurementswere also given aprikalim or its vehicle. Finally, aprikalim(1 mg/kg po for 2 days) or its vehicle was administered to ratswhich were concurrently treated with the ß-adrenoceptorantagonist atenolol (5 mg/ kg sc) or its vehicle. In cynomologusmonkeys, aprikalim produced focal and multifocal myocardialnecrosis of minimal to moderate intensity in or near the papillarymuscles of the left ventricle. These effects were abrogatedby nadolol. Similarly, necrotic lesions were caused by aprikalimonly in those rats which had not been pretreated with atenolol.In monkeys, aprikalim produced a marked and long-lasting decreasein aortic blood pressure, accompanied by an even more prolongedtachycardia. These results demonstrate that aprikalim can producemyocardial necrosis not only in rats but also in monkeys. Toour knowledge, this is the first time that such adverse effectsare reported for a vasodilator in monkeys. More importantly,these effects were prevented by blocking cardiac ß-adrenoceptors.Thus, the myocardial lesions produced by aprikalim may be attributedto its profound and prolonged hemodynamic effects.  相似文献   
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ABSTRACT. This case report concerns a 7-month-old infant with severe height retardation (–5.0 SD), typical growth hormone (GH)-deficient phenotype, and undetectable GH serum levels in response to three pharmacological stimuli. Diagnosis of isolated GH deficiency type 1A was confirmed by restriction endonuclease analysis of genomic DNA which pointed out GH-N gene deletion. The introduction of bio-methionyl-GH therapy in this patient was followed by a transient and clinically irrelevant appearance of low binding capacity GH antibodies as well as by a long-lasting catch-up growth (42.2 cm) which is continuing 44 months after beginning of treatment. This atypical pattern confirms that immune and growth response to exogenous GH in isolated GH deficiency 1A may be very heterogeneous.  相似文献   
8.
ABSTRACT. In Rwanda, both HIV infection and bacteraemia represent major health problems among paediatric populations. We carried out a prospective study to determine if bacteraemia is a marker of HIV infection among ambulatory and hospitalized Rwandese children. All children presenting at the Department of Paediatrics of the Centre Hospitalier de Kigali and who had their blood cultured during a two-month period were eligible for the study. One hundred and thirty-five children were included in the study. A pathogen was isolated from 36 children (26.7 %): S. typhimurium (10 cases), S. enteritidis (6), S. typhi (4), Str. pneumoniae (9). H. influenzae (6) and S. aureus (1). No association was found between bacteraemia and HIV seropositivity when all the children were considered. However, among patients less than 2 years old, bacteraemic subjects were more frequently ( p ≤0.05) HIV seropositive (44 %) than those with negative blood cultures (19 %). Our study shows that in young children in Central Africa, the presence of bacteraemia may be an important marker of HIV seropositivity.  相似文献   
9.
METHOD : It is possible to induce increased fetal resorption in a number of inbred murine matings by injecting Poly (I) Poly (C12U) 3.5 days postconception, a maneuver associated with natural killer-mediated damage to the feto placental unit such as occurs in spontaneous fetal resorptions. RESULTS : We show here that alloimmunization can block this effect. In addition, maternal immune responses induced by alloimmunization against isolated mutant class I or class II, as well as by immunization with class I MHC alloantigens (Kd) transfected L cells are sufficient to restore normal fetal viability. It is not necessary that the maternal immune response be specifically directed against paternal alloantigens fr the fetal protecton to ensue, since the effect occurs in inbred matings when the mother is immunized against unrelated class I or class II alloantigens. As in previous studies conducted in the murine species, not all MHC alloimmunizations are protective. In addition, as control, immunization with a monomorphic class I MHC molecular (37), transfected L cells, sheep red blood cells or hen egg lysozyme is without effect. CONCLUSION : These results indicate that defined MHC antigens can mediate fetal protection from induced fetal resorption, and suggest that one driving force in promoting MHC antigen polymorphism in mammals is their capacity to confer protection from NK mediated fetal demise.  相似文献   
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