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1.
Cell surface hydrophobicity, haemagglutination pattern and adherence to HeLa cells were examined in 230 strains of Escherichia coli collected from women (n = 61 strains) and children (n = 65 strains) with non-obstructive acute pyelonephritis and in 104 faecal control strains of E. coli from healthy adults (n = 71 strains) and children (n = 33 strains). Pyelonephritogenic E. coli strains showed a significantly increased incidence of hydrophobic properties (90%) and mannose resistant haemagglutination (MRHA) of human erythrocytes (83%) than faecal control strains (64 and 23% respectively, P less than 0.001 in both cases). Mannose sensitive haemagglutination (MSHA) was observed in 48% of the pyelonephritogenic E. coli strains and in 50% of the faecal control strains (NS). The incidence of adherence to HeLa cells was low both in pyelonephritogenic and faecal control strains, 6 and 7% respectively (NS). The bacterial phenotypes MRHA + MSHA + and MRHA + MSHA- appeared significantly more often in pyelonephritogenic E. coli strains (35 and 48% respectively) than in faecal control strains (5 and 17% respectively, P less than 0.001 in both cases). The phenotype MRHA- MSHA + occurred significantly more often in control strains (45%) than in pyelonephritogenic strains (13%, P less than 0.001). Eighty-three per cent of the pyelonephritogenic E. coli strains expressing hydrophobic properties showed MRHA and 50% of the hydrophobic strains showed MSHA. There were no significant correlations between cell surface hydrophobic properties and haemagglutination pattern or adherence to HeLa cells in pyelonephritogenic E. coli strains nor in faecal control strains.  相似文献   
2.
A technique using high pressure liquid chromatography gel filtration was used to evaluate GH-binding proteins (GH-BPs) in human plasma; eluate was monitored for radioactivity in a gamma-detection system connected to a computer. Plasma (200 microliters) was incubated with 125I-human (h) GH (200,000 cpm) at 4 degrees C for 20 hours. Our GH binding assay offers important gains in terms of rapidity and resolution; it has permitted a clear separation and characterization of the two GH-binding components present in human plasma.  相似文献   
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Central diabetes insipidus (DI) is extremely rare during the neonatal period. Most cases of central DI are secondary to a known aetiology. Substitutive treatment with desmopressin is effective with nasal or oral preparation, but doses are variable and must be tailored individually. We report on a case in a very low birth weight infant with an idiopathic central DI during the first month of life. He was successfully treated with oral desmopressin. The treatment was maintained after discharge with low doses desmospressin.  相似文献   
5.
Ultrasound examination in 8 patients with occlusive jaundice demonstrated non-lithiasic extrahepatic intracanalar obstacles, a malignant tumor in 4 and a non-tumoral process (granuloma on suture thread, ball sludge, hemobilia in 2 cases) in the other 4. Analysis of echographic data suggested possible differential diagnosis criteria for these two types of occlusion.  相似文献   
6.
Abnormalities of thyroid function, specially hypothyroidism, are common complications of head and neck irradiation for childhood cancer. Hyperthyroidism is rare and can be misdiagnosed. We report two observations of this condition. OBSERVATIONS: The first patient received conventional craniospinal irradiation for a localized medulloblastoma. Three years later, he presented with profuse sweating, irritability and paroxysmal tachycardia. Biologic evaluation revealed a peripheral hyperthyroidism. The patient was treated with antithyroidian hormonal treatment. The second patient received an irradiation for an undifferentiated nasopharyngeal carcinoma. Three years later, she developed a progressive thyrotoxicosis which was attributed to hyperthyroidism after six months of evolution. Hormonal treatment improved the clinical state after several weeks. CONCLUSION: Hyperthyroidism is a rare complication of head and neck irradiation. This condition justifies a periodic and prolonged evaluation of thyroid function.  相似文献   
7.
Spectrum of NSD1 mutations in Sotos and Weaver syndromes   总被引:8,自引:0,他引:8  
Interestingly, mental retardation was consistently more severe in patients with NSD1 deletions. Macrocephaly and facial gestalt but not overgrowth and advanced bone age were consistently observed in Sotos syndrome patients. We suggest therefore considering macrocephaly and facial gestalt as mandatory criteria for the diagnosis of Sotos syndrome and overgrowth and advanced bone age as minor criteria.  相似文献   
8.
Despite evidence of an interaction between cannabinoids and estrogen in the brain, little information is available regarding the consequences of this interaction on behavior. A within-subjects design was used to examine the effects of estrogen and delta9-tetrahydrocannabinol (delta9-THC) on learning and memory in ovariectomized rats responding under a multiple schedule of repeated acquisition and performance. Treatment with low physiological levels of estrogen, delivered in Silastic capsules, improved response accuracy without affecting response rate during acquisition. Estrogen also attenuated the ability of delta9-THC (0.56- 3.2 mg/kg) to decrease response accuracy and rate during acquisition and response accuracy during performance. Results indicate that estrogen can improve accuracy during acquisition of a nonspatial operant task and can attenuate delta9-THC- induced behavioral deficits.  相似文献   
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Urinary levels of tissue inhibitor of metalloproteinase 1 (TIMP-1) higher than those of matrix metalloproteinase 9 (MMP-9) during acute pyelonephritis have previously been associated with a higher degree of acute inflammation and of postinfective renal scarring. The aim of the present study was to evaluate possible mechanisms by which TIMP-1 could affect the scarring process already during the acute phase of inflammation. The growth of Escherichia coli, bactericidal activity of fresh human blood, and respiratory burst, spontaneous apoptosis, and trans-basement membrane migration of normal human granulocytes were studied in vitro in the presence of different concentrations of recombinant human TIMP-1. To imitate the "normal" environment during inflammation in the kidney, granulocytes were also incubated with a conditioned medium from E. coli-stimulated renal epithelial cells. In order to compare our data with the in vivo situation, blood and urinary leukocyte levels were analyzed for 40 children with acute pyelonephritis, together with urinary MMP-9 and TIMP-1 levels. TIMP-1 at a concentration of 500 ng/ml increased the bactericidal activity of blood, increased the respiratory burst of granulocytes, decreased phosphatidylserine exposure and caspase 3 activity, which are features of spontaneous apoptosis, and inhibited granulocyte transmigration. Moreover, in the patients with pyelonephritis, MMP-9/TIMP-1 ratios in urine correlated with the degree of leukocyte transmigration. Thus, our data suggest that TIMP-1 specifically blocks the transmigration of granulocytes into urine. Entrapped and activated granulocytes, protected from apoptosis, might excessively destroy renal parenchyma and thus contribute to the pathogenesis of renal scarring following acute pyelonephritis.  相似文献   
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