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排序方式: 共有200条查询结果,搜索用时 15 毫秒
191.
192.
Bilateral lesions were seen in the subpleural region in a 23-week-old aborted male fetus. This fetus was not macerated and showed no central nervous system abnormality on physical examination and vertebral magnetic resonance imaging (MRI). Postmortem examination revealed bilateral, paravertebral, subpleural, circumscribed, yellowish-white, fluent lesions 2.5 x 1 x 1 cm in size. These lesions were localized on the upper part of both lungs and there was no other internal malformation. Histological examination of lesions showed adult neurones and well-differentiated neural tissue with white and gray matter, choroid plexus, ependymal structures and, rarely, some peripheral neural cells in addition to immature neuroectodermal cells. These cells were more mature than those in the brain tissue. 相似文献
193.
Chemoprevention of 2-amino-1-methyl-6-phenyli-midazo 4,5-b pyridine-induced carcinogen-DNA adducts by Chinese cabbage in rats 总被引:1,自引:0,他引:1
METHODSSpragueDawleyratsweremaintainedfor10daysonbasaldietordietcontaining20%(w/w)freezedriedcabbagepowderpriortoadminist... 相似文献
194.
Lymphocyte Populations and Cellular Immune Reactions in Juvenile Rheumatoid Arthritis 总被引:1,自引:0,他引:1
Ten patients with juvenile rheumatoid arthritis and age- and sex-matched healthy controls were investigated in pairs. The patients were found to have both normal proportions and normal absolute numbers of T lymphocytes, B lymphocytes, and the Fc-receptor-bearing lymphoid cells in peripheral blood. No abnormality of mitogen-induced lymphocyte transformation was observed. Lymphocyte-mediated cytotoxicity induced by phytohemagglutinin (PHA) or anti-target cell antibodies was also found to be normal. As in an earlier study, impaired delayed hyper-sensitivity by skin testing was observed in the patient group, thus indicating a dissociation between in vivo and in vitro parameters of lymphoid cell function. 相似文献
195.
196.
Characterization of a spontaneous mutation in beta-thalassemia associated with advanced paternal age 总被引:1,自引:0,他引:1
We characterized the molecular defect in a Swiss patient with a spontaneous beta-thalassemia mutation. Cloning and DNA sequencing of her beta-globin gene revealed a new frameshift mutation due to a single nucleotide deletion at codon 64 of the beta-globin gene. Restriction site polymorphism showed that the mutation arose on her paternal chromosome. Direct sequencing of a polymerase chain reaction amplified DNA segment showed absence of the lesion in both alleles of her father's beta-globin gene and confirmed the spontaneous nature of this mutation. 相似文献
197.
Collins AF; Fassos FF; Stobie S; Lewis N; Shaw D; Fry M; Templeton DM; McClelland RA; Koren G; Olivieri NF 《Blood》1994,83(8):2329-2333
Several life-threatening complications of the common disorder sickle cell disease require management with red blood cell transfusions and, hence, long-term iron-chelating therapy. The efficacy of the oral iron chelator 1,2-dimethyl-3-hydroxypyrid-4-one (L1) has not previously been determined in patients with sickle cell disease. We compared the efficacy of L1 to that of standard-dose subcutaneous deferoxamine in four regularly transfused patients with homozygous sickle cell disease, who had evidence of severe iron overload and a history of poor compliance with deferoxamine. Determination of 24-hour urinary iron excretion conducted over 5 days immediately after transfusion showed that the mean daily urinary iron excretion induced by L1 at 75 mg/kg/d (0.48 +/- 0.23 mg/kg) was equivalent to that induced by deferoxamine at 50 mg/kg/d (0.39 +/- 0.06 mg/kg). In two of three patients studied, a significant (P < .025) increase in mean daily urinary iron excretion was achieved when the dose of L1 was increased to 100 mg/kg/d. Total iron balance studies, which quantitated both urinary and stool iron excretion on L1 and deferoxamine, determined that mean total daily iron excretion induced by deferoxamine (0.88 +/- 0.05 mg/kg) was significantly greater (P < .05) than that induced by L1 (0.53 +/- 0.17 mg/kg), attributable to the significantly greater stool iron excretion during deferoxamine treatment (0.50 +/- 0.16 mg/kg/d) compared with that measured during L1 treatment (0.12 +/- 0.08 mg/kg/d, P < .01). Stool iron excretion accounted for a significantly greater percentage of total iron excretion during deferoxamine treatment (59% +/- 20%) than during L1 treatment (23% +/- 14%, P < .01). These iron balance studies are the first to compare total iron excretion induced by L1 with that achieved by deferoxamine. They demonstrate that the mean total daily iron excretion during L1 treatment (0.53 +/- 0.17 mg/kg) is sufficient to maintain net negative iron balance in most regularly transfused patients with sickle cell disease. Because long-term compliance with L1 has been shown previously to be superior to that with deferoxamine in patients with homozygous beta-thalassemia, the use of L1 should increase the long-term effectiveness of iron chelation in patients with sickle cell disease. 相似文献
198.
The biological activity of the multifunctional cytokine interleukin-1 (IL-1) is mediated by its receptors. The aim of this study was to determine if an association exists between single nucleotide polymorphisms (SNPs) in the IL-1 type 1 and 2 receptor genes (IL1R1 and IL1R2) and the expression level of membrane-bound IL1Rs on subpopulations of mononuclear cells or serum levels of soluble IL-1 receptors. It was observed that healthy individuals with the genotype TT in SNP rs2234650:C>T had a lower percentage of intact CD14+ monocytes expressing IL1R1 on their surface. The SNP rs4141134:T>C in IL1R2 has also been associated with the percentage of intact CD3+ T cells expressing IL1R2. Furthermore, individuals carrying the CC allele of SNP rs4141134:T>C and the TT allele of SNP rs2071008:T>G in IL1R2 had a lower density of IL1R2s on the surface of CD14+ monocytes in lipopolysaccharide (LPS)-stimulated PBMC cultures. In summary, this study demonstrated that IL-1 receptor gene polymorphisms could be one of the factors influencing the expression of membrane-bound IL-1 receptors (IL1R) on immunocompetent cells. 相似文献
199.
Lavouisier FB Nogueira Edson C Morais Maria AD Brito Beatriz S Santos Doanny L Vale Bruno FF Lucena Fernando G Figueredo Glaucia MM Guedes Saulo R Tintino Celestina E S Souza Raquel BSS Nogueira Edinardo FF Matias Maria FB Morais-Braga Emídio VL Cunha Micheline A Lima Henrique DM Coutinho 《African health sciences》2014,14(2):372-376
Background
Multi-resistantmicroorganisms such as Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Candida tropicalis e Candida krusei are the main causes of microbial infections. Padina sanctae-crucis is a seaweed often used to check the contamination of ecosystems by materials such as heavy metals, but studies of the antimicrobial activity of the same seaweed were not found.Methods
The tests for the minimum inhibitory concentration and modulation of microbial resistance, with the use of ethanolic and methanolic extracts of Padina Sanctae-cruces combined with drugs of the class of aminoglycosides and antifungal were used to evaluate the activity against the cited microorganisms.Results
Was observed a modulation of antibiotic activity between the natural products and the E. coli and S. aureus strains, indicating a synergism and antagonism respectively.Conclusions
The results showed a moderate modulatory effect against some microorganisms studied. 相似文献200.
The molecular basis of beta-thalassemia in Lebanon: application to prenatal diagnosis 总被引:7,自引:0,他引:7
A study of the molecular lesions of beta-thalassemia in Lebanon revealed the presence of eight different mutations in 25 patients with Cooley's anemia. The IVS1 position 110 mutation predominated with a frequency of 62% and was almost invariably associated with Mediterranean chromosome haplotype I. Five other mutations commonly found in the Mediterranean area occurred with frequencies of 2% to 8%. In addition a G----C substitution in IVS1 position 5 (a lesion previously found in Chinese and Asian Indians) was demonstrated in a patient with Mediterranean haplotype IX. A new mutation at codon 29 was found in two other patients with haplotype II. The characterization of these beta-thalassemia mutations should allow the implementation of a prenatal diagnosis program in that country. 相似文献