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601.
Determinants of glomerular filtration rate in the dog 总被引:2,自引:0,他引:2
602.
The influence of 15 or 25 mg/m2 of daily oral hydrocortisone with fludrocortisone 0.1 mg/day on growth and laboratory findings was evaluated in a prospective randomised crossover trial over 12 months in 26 children with 21-hydroxylase deficiency. Nine non-salt losers had fludrocortisone stopped for a further six month period. Height velocity was significantly decreased during treatment with 25 mg/m2 as compared with 15 mg/m2. This was the most sensitive indicator of corticosteroid treatment excess. A dose dependent effect upon plasma concentrations of 17-hydroxyprogesterone, testosterone, and androstenedione was found but increased values were still detected in more than half of the determinations made during the 25 mg/m2 period. Height velocity and 17-hydroxyprogesterone concentrations were positively correlated. Growth hormone response to clonidine stimulation and insulin-like growth factor-1 concentrations were both within reference values and there was no difference between treatment periods. Withdrawal of fludrocortisone did not result in any difference for the non-salt losers. It was concluded that 25 mg/m2 of hydrocortisone depressed growth in children with congenital adrenal hyperplasia, and that full suppression, or even normalisation, of plasma concentrations of 17-hydroxyprogesterone and androgens should not be considered a treatment goal, but instead an indication of corticosteroid treatment excess. 相似文献
603.
Extrahepatic obstruction of the portal vein is a well known cause of portal hypertension in childhood, that causes severe morbidity. We evaluated 34 children (24 boys, 10 girls, age 4.5 months to 12 years, mean 5.5 ± 3.8 years) with this diagnosis, to define the clinical picture, laboratory changes, diagnostic tools and therapeutic modalities. Gastrointestinal bleeding was the commonest mode of presentation (64.7%), with the second being splenomegaly. The cause of the obstruction could be determined in 38.2% (13/34) of the subjects. At the beginning of the study the main diagnostic procedure was splenoportography although in more recent years pulsed duplex Doppler ultrasonography has been used. The follow up period was a median of 5 years (range 1–11 years). The mean number of bleeding episodes was 4.7 ± 5.9 (range 1–26), while nine patients never bled. There was no mortality. Ten patients underwent surgery, while sclerotherapy was performed on 10. Twenty-one patients received beta-blocker drugs. No difference was found among these therapeutic modalities. It is well established that the major risk for children with extrahepatic portal vein obstruction is gastrointestinal bleeding which is tolerated quite well. Surgery should be indicated only in children where bleeding cannot be controlled by medical means including sclerotherapy. 相似文献
604.
Observer performance tests were conducted to compare the effects on diagnostic accuracy of hard copy (film) versus video display and to determine the diagnostic merits of conventional negative ("white bone") versus positive ("black bone") video displays. Subjective preferences were elicited from each observer for each display modality, and diagnostic accuracy was determined with receiver operating characteristic analysis. Digitized chest radiographs were used, including normal and abnormal cases with a variety of subtle abnormalities. The hard copy was printed with a 1,024 X 1,024-matrix by a high-quality drum scanner in conventional white bone format only. The video images were displayed on a 1,023-line monitor (30 Hz, interlaced) in both white bone and black bone formats with fixed window and brightness settings. Most observers preferred hard copy to video, but preferences were sharply divided between white bone and black bone video. Diagnostic accuracy was significantly greater with hard copy than with video display, and the conventional white bone format was significantly superior in accuracy to the black bone display. 相似文献
605.
Gefter WB; Spritzer CE; Eisenberg B; LiVolsi VA; Axel L; Velchik M; Alavi A; Schenck J; Kressel HY 《Radiology》1987,164(2):483-490
Magnetic resonance (MR) imaging of the thyroid was performed with a 1.5-T system and local receiver coil in 19 "healthy" subjects and 34 patients with various focal and diffuse thyroid disorders. The normal gland was typically homogeneous with increased intensity relative to that of muscle on images obtained with long repetition times (TRs) and long echo times (TEs). Adjacent structures in the neck and upper mediastinum were well displayed. Thyroid nodules as small as 4-5 mm were identified. Follicular adenomas appeared as well-circumscribed nodules of heterogeneous intensity, increasing significantly in signal with long TRs/TEs. Colloid cysts and hemorrhagic cysts had homogeneous high signal with both short and long TRs/TEs. Two of three carcinomas were seen as poorly marginated lesions with associated cervical lymphadenopathy clearly depicted as increased intensity with long TRs/TEs. A follicular adenoma containing microscopic papillary carcinoma appeared similar to other benign adenomatoid nodules. A functioning nodule was isointense with normal gland at all pulse sequences. Characteristic patterns of diffuse abnormality were observed in cases of multinodular goiter, Hashimoto thyroiditis, and Graves disease, although additional cases are required to determine specificity. High-field-strength surface-coil MR imaging appears to be a sensitive method for identifying gross morphology of focal, multinodular, and diffuse disorders of the thyroid and involvement of surrounding structures in the neck. 相似文献
606.
We report that erythroid-potentiating activity (EPA), known to stimulate the proliferation of normal human erythroid precursors in vitro, has a growth-promoting effect on human K562 erythroleukemia cells and Friend mouse erythroleukemia cells. Detailed studies were carried out using an EPA produced by a human T-lymphoblast line (Mo). Although EPA has not been purified to homogeneity, several observations indicate that the factor elaborated by Mo cells that stimulates erythroleukemia cell growth is the EPA molecule. The erythroleukemia growth factor cofractionates with EPA using gel exclusion chromatography, isoelectric focusing, and ion exchange chromatography. In addition, the activities exhibit similar kinetics of heat inactivation. A granulocyte-macrophage colony-stimulating factor also elaborated by Mo cells had no effect on the growth of the erythroleukemia cells. Other sources of EPA, such as peripheral blood leukocyte-conditioned medium, preparations from urine of anemic patients, and medium conditioned by a human monocyte-like cell line, stimulated erythroleukemia cell growth. Mouse sources of EPA (termed "burst-promoting activity") stimulated mouse but not human erythroleukemia cells. The availability of cell lines apparently responsive to EPA should prove useful for examining the mode of action of this regulator of erythropoiesis. 相似文献
607.
Cabrera Pivaral CE Martínez Ramírez A Vega López MG González Pérez G Muñoz De La Torre A 《Cadernos de saúde pública / Ministério da Saúde, Funda??o Oswaldo Cruz, Escola Nacional de Saúde Pública》1996,12(4):525-530
Nutritional practices of diabetics reflect both human behavior and the health culture of such patients. They also represent how the diabetic deals with the health/illness issue. The purpose of this survey was to identify and relate nutritional practices with metabolic control, age, sex, years of schooling, and time since diagnosis of illness. The sample was taken from 114 cases selected through systematic random sampling in five family practice units in Guadalajara. Using thirteen structured, coded, and quantified questions of the Likert type, the study evaluated nutritional practice with a range of 0-65. Results showed that 21% of the diabetics had appropriate nutritional practices (>31 points), and when related with years of schooling and time since diagnosis of illness, they showed statistically significant differences (p=0.05). Simple regression showed that 9% of metabolic control can be explained by nutritional practices. 相似文献
608.
Effect of sustained inflations applied directly after cord clamping on lung function in premature newborn lambs 总被引:1,自引:0,他引:1
WAA Klöpping-Ketelaars WJ Maertzdorf CE Blanco 《Acta paediatrica (Oslo, Norway : 1992)》1994,83(10):1017-1021
We studied the possibility of improving lung volume and therefore clinical outcome in premature newborn lambs by increasing the inspiratory volumes during the first minute after birth. Sixteen lambs from eight were delivered by hysterotomy after 130–131 days' gestation. In eight lambs the lungs were inflated with a bag with a sustained inspiratory inflation (SI) of 5 s and expiratory time of 5 s during the first four inflations after cord clamping and then mechanically ventilated. Their siblings did not receive SI and served as a control group. At 8 h postnatally, the SI and control groups showed the following results (mean ± SEM): mean airway pressure 14.8 ± 1.8 cmH2 O versus 11.9 ± 1.1 cmH2 O, PaO2 41.5 ± 7.3 kPa versus 31.3 ± 7.7kPa, alveolar-arterial oxygen gradient 359 ± 55 mmHg versus 437 ± 58 mmHg. Clinical course, incidence of pneumothorax, oxygenation index, total static compliance, parenchymal-alveolar air area ratio or mortality rate were not different. There was no significant difference between the two groups at this time or at any other time during the experiments. 相似文献
609.
BD Riggeal GP Crucian P Seignourel CE Jacobson IV MS Okun RL Rodriguez Hubert H Fernandez 《Neuropsychiatric Disease and Treatment》2007,3(6):955-958
We performed an analysis of prospectively-acquired cross sectional data on 106 Parkinson disease (PD) patients who underwent comprehensive neuropsychological testing and the Unified Parkinson Disease Rating Scale (UPDRS) motor scale. A significant correlation between the UPDRS motor and neuropsychological tests in all cognitive domains except for general intelligence and visuo-spatial function was seen. In this study, cognitive decline within this PD cohort correlated with motor impairment but not disease duration. Our findings suggest that overall cognitive impairment (except visuospatial dysfunction) may track motor progression in PD more than duration of disease. Longitudinal studies are needed to confirm our results. 相似文献
610.