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31.
Thirteen biochemical parameters and five enzymatic activities were determined on sera of 63 normal human fetuses sampled by direct puncture under ultrasound guidance, between the 20th and the 26th wk of gestation, and on their mothers. They were referred to us for various prenatal diagnoses but were well and confirmed healthy at birth. Some parameters were found to be very similar in both groups, mainly creatinine, calcium, creatine kinase, aspartate aminotransferase, and gamma-glutamyl transferase. Some values were significantly higher in the fetuses, such as total bilirubin, direct bilirubin, phosphorus, lactic dehydrogenase and alkaline phosphatase activities, and alpha-fetoprotein. Urea, uric acid, glucose, triglycerides, cholesterol, total protein, and albumin levels were found to be lower in fetuses. These data indicate a slower metabolism in fetuses compared to their mothers, a lower level of energy requirement, and a relative liver immaturity. These normal values of fetal biochemistry will improve our knowledge of physiology and help to determine the specific values of a test in fetal pathology.  相似文献   
32.
PURPOSE: To investigate in vitro the cell toxicity and antioxidant effects of two major tear substitutes, hyaluronic acid and a widely used carbomer, with and without preservative. METHODS: Chang conjunctival cells were treated with different concentrations of unpreserved or preserved carbomer 934P (0.03% and 0.3%), unpreserved or preserved hyaluronic acid (0.018% and 0.18%), and benzalkonium chloride (BAC 0.0005% and 0.005%) for 15 minutes or for 15 minutes with 24 hours of cell recovery, according to previously validated methods. Microplate cold light cytofluorometry was performed to evaluate cell viability (neutral red test), chromatin condensation (Hoechst 33342 test), and reactive oxygen species (ROS) production (dichlorofluorescein diacetate and hydroethidine tests). Confocal microscopy was used to explore morphologic changes. RESULTS: No alterations were found with unpreserved and preserved hyaluronic acid at all concentrations and times tested. A decrease in cell viability with chromatin condensation appeared with 0.3% preserved carbomer 934P at the two times tested. This cytotoxicity, however, was significantly less than that observed with BAC alone, although the same concentrations of preservative were used. Unpreserved carbomer 934P induced no modification of cell viability after 15 minutes but a significant decrease in chromatin condensation, reversible after 24 hours of cell recovery, when a delayed decrease in cell viability was observed. Production of reactive oxygen species (ROS) decreased with the four formulations of tear substitutes tested at their usual concentrations, whereas a significant production of ROS occurred with BAC. CONCLUSIONS: These two ophthalmic hydrogels have no cytotoxicity but possess antioxidant properties and tend to reduce the toxic effects of preservatives. These results may allow use of hydrogels, not only in dry eye but also in ocular surface disorders involving oxidative stress and in ophthalmic drug therapy to improve ocular tolerance.  相似文献   
33.
Neonatal screening for phenylketonuria (PKU) has created a problem as females with PKU are reaching child-bearing age. Surveys have revealed that maternal phenylalanine blood concentrations greater than 1200 μmol/l are associated with fetal microcephaly, congenital heart defects and intrauterine growth retardation. It is estimated that as many as 3000 hyperphenylalaninemic females may be at risk of producing these fetal abnormalities. To examine this problem, the international maternal PKU collaborative study was developed to evaluate the efficacy of a phenylalanine-restricted diet in reducing fetal morbidity. Preliminary findings have indicated that phenylalanine restriction should begin before conception for females with PKU planning a pregnancy. Dietary control should maintain maternal blood phenylalanine levels between 120 and 360 μmol/l and should provide adequate energy, protein, vitamin and mineral intake. Pregnant hyperphenylalaninemic females who achieved metabolic control after conception or by the 10th week of pregnancy had a better offspring outcome than anticipated. The results of 402 pregnancies are reviewed.  相似文献   
34.
A 4 year old girl treated with a standard chemotherapy protocol for acute lymphoblastic leukaemia developed hepatic candidosis during the consolidation phase. This relapsed after a prolonged course of amphotericin B and flucytosine. An eight week course of liposomal amphotericin produced a marked clinical improvement which was sustained for one year. A subsequent relapse was associated with transformation to myelodysplastic leukaemia.  相似文献   
35.
The presence of circulating immune complexes (CIC) has been documented in systemic lupus erythematosus (SLE), rheumatoid arthritis (RA) and ankylosing spondylitis (AS) by various investigators. It has been suggested that these may be used as probes to identify antigens playing a role in these pathological processes. Using a solid-phase cross-reaction assay to establish if these complexes reacted with each other in specific disease groups, it was found that polyethylene glycol (PEG) precipitates of six AS patients cross reacted in 29 of 36 tests, but reacted with SLE and RA PEG precipitates in only two of 24 tests in each case. SLE PEG precipitates cross-reacted in four of 14 tests and reacted with none of the six AS and four RA precipitates. Similarly, RA PEG precipitates did not cross-react (none of 16 tests), nor did they react with AS (none of 24 or SLE precipitates (none of 16). Similar results were observed when IgG, obtained after acid dissociation on sucrose density gradients of CIC isolated by PEG precipitation and staphylococcal protein A chromatography, was used as the solid phase component. F (ab')2 fragments with similar antibody specificity were obtained by pepsin digestion of isolated CIC from three of six AS patients. These bound radiolabelled AS PEG precipitates (2.02-2.40%) significantly more than SLE (0.22-0.28%) or RA (0.29-0.35%) precipitates. These studies demonstrate the feasibility of obtaining F (ab')2 fragments with antibody activity from isolated CIC and the presence of a disease specific antibody specificity in AS CIC. The nature of the antigen involved remains to be elucidated. Such a cross-reactive antibody specificity was not found in RA nor SLE CIC.  相似文献   
36.
Free and conjugated catecholamines (dopamine, noradrenaline, adrenaline) and their methoxylated and/or deaminated metabolites were studied in rat urine after the bilateral destruction of the A10 dopaminergic cell group. Two months after the lesion, dopamine (DA) loss reached 91% in the nucleus accumbens, and was greater than 80% in olfactory tubercles, lateral septum and frontal cortex. At the same time urinary conjugated dihydroxyphenylacetic acid (DOPAC) was decreased by 45% whilst homovanillic acid (HVA) was increased only in its sulfated form (+62%). In contrast, no changes were observed in the free and conjugated forms of urinary DA, 3-methoxytyramine noradrenaline, normetanephrine, adrenaline, vanylmandelic acid, 3-methoxy-4-hydroxyphenylglycol and in the free forms of DOPAC and HVA.The present report confirms and extends our previous findings on the relationships between central dopaminergic activity and urinary deaminated metabolites of DA in the rat. It emphasizes the interest of urinary assays which could provide in vivo information on CNS functions.  相似文献   
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38.
We investigated the effect of Brussels sprouts, inulin and a fermented milk on the faecal microbiota diversity of human microbiota-associated (HMA) rats by PCR-temporal temperature gradient gel electrophoresis (PCR-TTGE) using universal and group-specific 16S rRNA gene primers. The HMA rats were submitted to a control diet for 10 d (initial time), then switched to the experimental diets for 4 weeks (final time). Using universal primers, the mean degree of similarity between all faecal samples at initial time was 80.8 %. In the group consuming the control diet throughout the experiment, the mean degree of similarity between the PCR-TTGE profiles at initial v. final time was 76.8 %, reflecting a spontaneous temporal variation. The mean degree of similarity between control and experimental groups at final time was lower, 72.4 %, 74.4 % and 75.6 % for inulin, Brussels sprouts and fermented milk, respectively, indicating a dietary effect on the predominant populations. Using specific primers, bifidobacteria could be detected only in those rats that had consumed inulin, showing a specific increasing effect of this dietary compound. The Lactobacillus population was very heterogeneous at initial time but tended to homogenize within each dietary group. At final time, caecal contents were collected for analysis of SCFA and beta-glucuronidase activity. Inulin and Brussels sprouts increased the butyrate and acetate proportion, respectively, while the fermented milk did not modify the caecal biochemistry. This experiment shows for the first time that cruciferous vegetables are able to alter the diversity and the metabolic activities of the digestive microbiota in HMA rats.  相似文献   
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