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121.
122.
目前国内超声医学界对最佳耦合剂声阻数值的选择尚无较为准确的说法。作者从声束通过介质薄层透射率公式出发,用近似计算方法,找出了最佳耦合剂数值的大小,并对适宜的声头材料、耦合剂材料提出建议。 相似文献
123.
Mental Health of Mothers of Children with Juvenile Rheumatoid Arthritis: Appraisal as a Mediator 总被引:1,自引:3,他引:1
Lustig Julie L.; Ireys Henry T.; Sills Edward M.; Walsh Beverly B. 《Journal of pediatric psychology》1996,21(5):719-733
Examined direct and mediated relations between condition parametersand maternal mental health for 53 mothers of 2- to 11-year-oldchildren with juvenile rheumatoid arthritis (JRA). Multivariateanalyses revealed that when considered simultaneously, indicesof both biological severity and functional severity were associatedsignificantly with maternal mental health. Further, mother'sappraisals of the impact of the child's illness on the familypartially mediated the effects of medication type and child'sfunctional status on mother's mental health. Results providesupport for conceptual models that emphasize the cognitive mechanismsby which condition parameters such as biological and functionalseverity might affect maternal mental health. Explicating theprocesses by which a child's JRA might lead to psychologicaladjustment problems in the parent has implications for developingpreventive and treatment interventions. 相似文献
124.
计算机嗓音测试参数的特点及临床意义 总被引:5,自引:0,他引:5
电子计算机嗓音测试及频谱分析已成为嗓音客观检查的重要手段。其测试参数为喉部疾病诊断、疗效评价的主要指标。但嗓音的声学参数是一种多维函数,与声带振动的生物力学密切相关。为了更好的理解和掌握嗓音的声学参数,对嗓音测试的参数进行详细的分析。以便于准确地选用和科学、客观地评价嗓音。 相似文献
125.
Yu. P. Denisov P. V. Sergeev N. P. Saksonov G. V. Shutko 《Bulletin of experimental biology and medicine》1980,89(2):147-150
Parameters of binding of cortisone and estradiol to plasma membranes of rat hepatocytes were studied by the method of liquid scintillation radiometry. The presence of two systems for the binding of these hormones in the membranes was demonstrated. One system is specific (saturable) and binds hormones in physiological concentrations. The capacity and affinity of this system for cortisone are significantly higher than for estradiol. The binding parameters within the temperature range from 4 to 37°C for cortisone and estradiol respectively are: Dissociation constant 2.1–3 and 2.7–4.5 nM, number of binding sites 2–2.4 and 0.14–0.18 nmoles/mg protein. Experiments with p-chloromercuribenzoate demonstrate the role of proteins in the working of this system. The second (unsaturable) system is nonspecific and its function is determined by the lipid component of the membranes. The affinity of corticosteroids for hepatocytes is probably due to the activity of the (saturable) specific system of the plasma membranes of these cells.Department of Molecular Pharmacology and Radiobiology, Medico-Biological Faculty, N. I. Pirogov Second Moscow Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR N. A. Yudaev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 89, No. 2, pp. 172–174, February, 1980. 相似文献
126.
The membrane properties of the neurons located in the ventral part of the periaqueductal grey (PAG) of the guinea-pig were studied using an in vitro slice preparation. Cells had low values of resting membrane potential (-53.3 +/- 1.3 mV, mean +/- standard error), high input resistance (195. +/- 16.2 M ohm) and moderate values of membrane time constant (12.6 +/- 0.7 ms). The last two parameters changed as recordings were made along the sagittal axis, higher values corresponding to the more rostral cells. Three main neuronal types-fusiform, triangular and stellate-were found in the ventral PAG using intracellular injection of Lucifer yellow. A study of the cell number and cell density was carried out in coronal and sagittal sections of the ventral PAG. This analysis showed a clear gradient of size in this region arising from the gradual disappearance of large (17 to 40 microm) neurons in the caudorostral direction. The neuronal density also increased in this direction. Therefore, some electrotonic and morphological parameters differ along the sagittal axis. These findings suggest a larger neuronal heterogeneity of the caudal part of the PAG, and might contribute to a functional segregation of this region. 相似文献
127.
Summary The study concerns the clinical outcome and later prognosis (regarding permanent insulin treatment) of patients who develop insulin-dependent diabetes mellitus during pregnancy (which is different from gestational diabetes). Sixty-three such patients (27±1 (SEM) years old) were delivered at the Copenhagen Centre for Diabetes and Pregnancy during the years 1966–1980. Obstetric complications such as toxaemia were seen in 9.5% of these study patients and the perinatal mortality was 6.3%, both percentages being higher than in the general population (1.1%,p<10–7 and 1.0%,p<10–3, respectively), but similar to those observed in patients with Type 1 diabetes diagnosed before pregnancy. In contrast, the frequency of malformations was 1.6%, the same as in the general population (1.4%), but lowerthan that seen in patients with long-standing diabetes (8.3%,p<0.05). At follow-up examination 8±1 years after diagnosis all patients were diabetic; 77% were insulin treated, having no or virtually no residual B-cell function, and were clearly Type 1 diabetic patients. After delivery 80% of the patients had a remission period (median 256 days) without insulin treatment. This remission period was absent or shortest in patients with the following characteristics (p0.03): low age, first parity, not overweight, and high blood glucose level at diagnosis. These prognostic parameters should be considered in obligatory, clinical follow-up plans for such patients. 相似文献
128.
回顾性分析1990~1993年全国28省、市、自治区233所医院,住院分娩的孕满28周的2158例神经管缺陷儿的产前诊断情况,了解我国神经管缺陷儿产前B型超声波诊断情况.结果显示:我国神经管缺陷产前诊断的比例为61.8%,产前B型超声波诊断的比例为56.5%,其中无脑畸形、脑膜脑膨出、脊髓外翻的产前B型超声波诊断比例分别为66.7% 、62.5%、52.5%.胸段(46.4%)、腰段(43.4%)的脊柱裂产前B型超声波诊断的病例较颈段 (35.5%)、骶段(31.7%)高(P<0.05).省级、市级、县级及部队工矿医院神经管缺陷的产前B型超声波诊断比例分别为55.7%、59.4%、49.0%、57.2%.1991~1993年神经管缺陷产前B型超声波诊断比例分别为53.5%、55.8%、60.7%、54.7%.无脑畸形、脑膜脑膨出、脊髓外翻产前B型超声波诊断的比例较高. 相似文献
129.
青海省甘德县人群包虫病流行病学调查 总被引:1,自引:0,他引:1
用Dot-ELISA和B超、X线在果洛州甘德县进行了人群包虫病的流行病学调查。结果表明,人群包虫病血清阳性率为10.83%。男性和女性分别为9.29%和12.92%。B超、X线检查阳性率为5.77%,男性和女性分别为4.83%和7.05%。女性高于男性不同职业血清阳性率和B超、X线检查阳性率均以牧民最高(17.56^和11.56%)随年龄增加,人群包虫病血清阳性率和B超、X线检查阳性率越高。不同地 相似文献
130.