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991.
992.
Quantitative analysis of the trace element content of human intervertebral discs (IVDs) is essential because it can identify specific enzymes or metabolites that may be related to human intervertebral disc degeneration (IVDD). The goal of this study was to assess the concentrations of copper (Cu), iron (Fe), manganese (Mn), lead (Pb), zinc (Zn), sodium (Na), magnesium (Mg), potassium (K), phosphorus (P), and calcium (Ca) in serum samples obtained from patients with IVDD in comparison to healthy volunteers (a control group). The study group consisted of 113 Caucasian patients qualified by a specialist neurosurgeon for microdiscectomy. The control group consisted of 113 healthy volunteers who met the eligibility criteria for blood donors. The examined clinical material was the serum samples obtained from both groups.Based on the quantitative analysis of selected elements, there were statistically significantly (p 0.05) higher concentrations of Cu (1180 μg/L±800 μg/L vs. 1230 μg/L±750 μg/L), Zn (790 μg/L±300 μg/L vs. 850 μg/L±200 μg/L), and Mg (21730 μg/L±4360 μg/L vs. 23820 μg/L±4990 μg/L) in the serum of healthy volunteers compared to those in the study group. In addition, statistically significant changes were not detected in the concentrations of any elements among either sex in either the study or control group or in their body mass index (BMI) values (p > 0.05). In the serum samples from the study group, the strongest relationships were noted between the concentrations of Zn and Pb (r = 0.61), Zn and P (r = 0.69), Zn and Ca (r = 0.84), Zn and Cu (r = 0.83), Mg and Ca (r = 0.74), and Ca and P (r = 0.98).It has been indicated that, above all, the concentrations of Cu, Zn, Ca, and Mg depend on the advancement of radiological changes, according to the Pfirrmann scale. However, no influence on pain intensity was found, depending on the concentration of the assessed elements.The analysis indicates that the determination of serum Cu, Zn, Ca, and Mg concentrations may have diagnostic significance in predicting the onset of lumbosacral IVDD. The predictive evaluation of changes in the concentrations of selected elements in patients with degenerative lumbar IVD lesions appears to be a promising, cost-effective strategy. 相似文献
993.
We used 8 morphological traits and 17 simple sequence repeats loci to characterize 71 cultivated and wild Tunisian fig trees (Ficus carica L.). Significant morphological differences were inferred from leaf traits. The statistical analysis showed two major fig groups that indicated a common morphological basis. A total of 74 SSR alleles was revealed, defining 63 unique multilocus genotypes indicating a substantial genetic diversity. Based on multilocus SSR genotypes an identification key was established using MFC30, MFC3, MFC11 and MFC19 loci to identify figs. Analysis of variance components of linkage disequilibrium shown that among 136 pairs of loci, 32 present a significant gametic disequilibrium. The parameter D′2IS (0.1284) was greater than D′2ST (0.0079), a pointer of close to zero variance in total simple, and consequently the more pronounced independence of the 17 SSR loci. The majority of Ohta's variance components of linkage disequilibrium followed a pattern caused by genetic drift or a non-systematic disequilibrium profiles and natural selection occurs only for LMFC24-MFC8 pair loci in cultivated figs. Our results suggest that the morphological and SSR markers are suitable to characterize figs and should be recommended in conservation management strategy. 相似文献
994.
996.
ABSTRACT. Miamiensis avidus, a marine scuticociliate, undergoes microstome to macrostome transformation. This process is induced by prey ciliates. the morphogenesis of this process was examined using scanning electron microscopy and light microscopy of quantitative protargol-stained specimens. Several stages are identified and described. 相似文献
997.
B. A. Ebsary 《Journal of nematology》1983,15(3):363-366
Pungentus porosus n. sp. is described and illustrated. The differential characters are a short odontostyle of 6-8 μm or slightly less than one head width, vulva at 44-50%, goblet-shaped amphids, presence of a prevulval uterine sac, and a hemispherical tail with a variable number of pores. Pungenlus sublatum, P. vesiculosus, P. orthocephalus, P. granosus, and P. parvus sensu Eroshenko are considered to be incertae sedis. A key is provided to the 21 valid species of Pungentus. The following species are new Canadian records: P. angulosus, P. clavatus, P. engradinensis, P. marietani, P. microdentatus, P. monohystera, P. obscurus, P. parvus, P. pungens and P. silvestris. 相似文献
998.
G. Weber 《Biochemistry. Biokhimii?a》2001,66(10):1164-1173
Our introduction of the molecular correlation concept and the key enzyme concept and the use of biologically meaningful tumor models and control systems resulted in the discovery of an ordered pattern of enzymic and metabolic imbalance and the elucidation of the linkage with transformation and progression. We showed that the biochemical and enzymic pattern of alterations was the result of a reprogramming of gene expression that was both quantitative and qualitative and was characteristic to neoplasia, since no similar pattern of imbalance was observed in any of the control normal, regenerating, or differentiating tissues. Important aspects of gene logic were identified. These include demonstration of operation of reciprocal control of activities of opposing key enzymes and antagonistic pathways of synthesis and catabolism in pyrimidine, purine, ornithine, and carbohydrate metabolism and recently in signal transduction. The extent of increase in the activities of key enzymes of pyrimidine and purine biosynthesis related to the absolute activity of the enzymes in resting liver. The qualitative alterations in gene expression included the isozyme shift of key regulatory enzymes. We identified a segment of gene expression that is essential for neoplasia. We pointed out the selective advantages that reprogramming of gene expression confers to cancer cells. Understanding these alterations in the enzymology and biochemistry of cancer cells made it possible to identify potentially sensitive targets for anticancer chemotherapy. In recent clinical studies we targeted the increased IMP dehydrogenase activity in leukemic blast cells by an inhibitor drug, tiazofurin, and achieved 77% responses, including complete remissions. 相似文献
1000.
Patterns of confounding in factorial designs 总被引:1,自引:0,他引:1