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961.
Dietary fibers are widely used in hypoglycaemic, hypolipidemic, slimming diets. It is probable that their ingestion coincides with the oral administration of drugs and a modification of their pharmacokinetics can appear. In the present study, the influence of two soluble fibers (guar gum and psyllium) was evaluated on the pharmacokinetics of ethinyloestradiol (EE) when they were administered together to female rabbits via the oral route. Three groups of rabbits were used. All animals received 1 mg/kg of EE; this compound was administered alone in the control group and with 3.5 g of guar gum or psyllium in the other two groups. When guar gum was administered, there was a decrease in the extent of EE absorbed, but no change was observed in the rate of absorption. When psyllium was administered, the extent of EE absorbed increased slightly and the rate of absorption was slower.  相似文献   
962.
963.
The effects of polymorphonuclear neutrophils (PMNs) and/or clavulanic acid on the bactericidal activity of amoxicillin (at human serum achievable concentrations) against a serotype 3 penicillin-susceptibleStreptococcus pneumoniae strain [minimal inhibitory concentration /minimal bactericidal concentration (MIC/MBC) values of penicillin, amoxicillin, and amoxicillin/clavulanic acid (2:1)=0.01/0.01 g/ml] and a serotype 9 penicillin-resistant strain [MIC/MBC of penicillin, amoxicillin, and amoxicillin/clavulanic acid (2:1)=1/2 g/ml] were studied. Against the penicillin-resistant strain, subinhibitory concentrations of amoxicillin reduced the growth rate; this effect was increased by the addition of clavulanic acid. A reduction of the penicillin-resistant initial inocula (3 × 106 cfu/ml) at subinhibitory concentrations was obtained only with amoxicillin plus clavulanic acid and PMNs. At suprainhibitory concentrations, both clavulanic acid and PMNs increased the bactericidal activity of amoxicillin, as evidenced by an increased reduction in the penicillin-resistant initial inocula. The combined effect of these antibiotics and immune defenses may help explain the maintenance of their clinical efficacy in respiratory tract infections, despite the increase in the incidence of penicillin-resistant pneumococci.  相似文献   
964.
X-linked dysmorphic syndrome with mental retardation   总被引:1,自引:0,他引:1  
F. Prieto    L. Badía    F. Mulas    A. Monfort  F. Mora 《Clinical genetics》1987,32(5):326-334
We present a dysmorphic syndrome in eight males of the same family (four brothers, three cousins and one uncle) that is characterised by: mental retardation, facial dysmorphia, abnormal growth of teeth, skin dimple at the lower back, clinodactyly, patella luxation, malformation of lower limbs, abnormalities of the fundus of the eye and subcortical cerebral atrophy. These physical defects do not correspond to any previously described syndrome, which suggests that it is a new syndrome. According to the model of heredity this syndrome could be due to a mutant gene situated in the X-chromosome.  相似文献   
965.
The present study assesses the clinical usefulness of the hepatitis C core antigen assay for monitoring of patients being treated for chronic hepatitis C virus (HCV) infection. Eighty-six serum samples were selected at random from 16 patients and levels of HCV RNA and HCV core antigen were determined simultaneously and in parallel to compare both techniques. The data obtained were compared by Pearson’s correlation and the coefficients calculated by Fisher transformation and by calculating the difference and standard error. A good linear correlation was observed between both techniques. Maximum correlation, with significant difference, was found between patients infected with the 1a genotype and other genotypes. In conclusion, the HCV core antigen assay is useful for the diagnosis of early infection; however, its use for determining the exact timing of viral elimination during treatment is clearly unsuitable.  相似文献   
966.
Cytogenetic studies in 18 patients with secondary blood disorders   总被引:1,自引:0,他引:1  
Cytogenetic studies were carried out in 18 patients with secondary blood diseases; 15 patients had a history of prior malignancy, two had been professionally exposed to carcinogenic agents, and one patient had been treated with immunodepressors. The interval between initial therapy and secondary disease ranged from 13 to 123 months, with a mean of 57.8 months; the mean survival time from the diagnosis of secondary disease was 6 months. Cytogenetic abnormalities were present in 83% of cases, with a trend to hypodiploidy in 90%. The most often involved chromosomes were #5, #7, and 3p. A correlation between the cytogenetic abnormalities and etiologic factors has been analyzed; data from the present series and from the literature suggest a correlation between chromosome #7 and chemical agents, and chromosomes #11, #12, and #17 and physical agents.  相似文献   
967.
The protein-free terminal fragments HindIII B and L, from the left and right ends of phi 29 DNA, respectively, but not internal fragments of similar size, were active as templates in the formation of the p3-dAMP initiation complex in an in vitro system containing purified phi 29 terminal protein p3 and DNA polymerase p2, although the activity was lower than that obtained with the phi 29 DNA-p3 complex. These results indicate the existence of specific sequences at the ends of phi 29 DNA that allow the initiation of phi 29 DNA replication. The template activity of the protein-free terminal fragments was size dependent. The protein-free single strands of the HindIII L fragment were much less active than the corresponding double-stranded fragment. Terminal protein-DNA complexes of phages PZA and phi 15, with a terminal protein closely related to the phi 29 protein p3, were more active as templates in the initiation reaction with the purified phi 29 proteins than the corresponding protein-free DNAs, as it happens in the case of phi 29. However, the terminal protein-DNA complexes of phages Nf, B103, and GA-1, with a terminal protein less related or unrelated to the phi 29 protein p3, were essentially inactive and became active after removal of the parental terminal protein. These results strongly suggest that the parental terminal protein is the major signal in the template for the initiation of phi 29 DNA replication.  相似文献   
968.
We report a patient with allergic conjunctivitis and blepharitis as a result of tobramycin eyedrops.  相似文献   
969.
Spinocerebellar ataxia type 6 (SCA6) is an autosomal dominant cerebellar degeneration caused by the expansion of a CAG trinucleotide repeat in the CACNA1A gene. Mutations in patients are characterised by expanded alleles of between 21 and 30 repeat units and by extreme gonadal stability when transmitted from parents to children. We have investigated the SCA6 mutation in a large Spanish kindred in which previously reported spinocerebellar SCA genes and loci had been excluded. We observed a 23 CAG repeat expanded allele in the 13 clinically affected subjects and in three out of 10 presymptomatic at risk subjects. Transmission of the mutant allele was stable in six parent to child pairs and in 29 meioses through the pedigree. Linkage analysis with the SCA6-CAG polymorphism and marker D19S221 confirmed the location of SCA6 on chromosome 19p13. The molecular findings in this large family confirm the expansion of the CAG repeat in the CACNA1A gene as the cause of SCA6 and the high meiotic stability of the repeat.  相似文献   
970.
The case is reported of a 45 year old woman with the rare leukaemia of natural killer cell large granular lymphocyte (NK/ LGL) type. Cytometric analysis of leukaemic blasts showed that they were positive for CD2, CD38, and CD56 antigens but negative for a series of antigens including CD3, CD7, CD16, and HLA-DR. Rearrangements of the beta T cell receptor, and heavy and kappa immunoglobulin genes were not detected and neither were chromosomal abnormalities. Leukaemic blasts developed NK cytotoxicity. The patient failed to respond to aggressive chemotherapy and died three months after diagnosis. The lack of expression of HLA-DR is an extraordinary characteristic of this case, as all cases of acute NK cell leukaemias described to date expressed HLA-DR. The immunophenotype observed in the NK cell leukaemic blasts may represent the counterpart of a hypothetical normal cell precursor in an early stage of ontogenic NK cell development.  相似文献   
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