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11.
Lobomicosis     
The ninth Colombian case of Lobomycosis is presented, along with a review of the Colombian literature. The clinical, histopathological, and mycological aspects are summarized emphasizing the peculiar birefringent appearance of Lobomyces when examined under polarized light.  相似文献   
12.
The pleiotropic effects of transgenesis includes different consequences of the insertion of a transgene that are not related to the direct action of its product. It is necessary to evaluate the outlook for the application in selection of the transgenic potato strain containing the bacterial chitinase gene chiA we created for studying the possible nonspecific influence of the introduction of the transgene on the phenotypical properties of the transgenic lines. In the present investigation we will consider the effect of the introduction of the chitinase transgene on such agronomically important characteristics as yield and nonspecific resistance.  相似文献   
13.
In patients suffering from Parkinson's disease (PD), we analyzed correlations between the parameters of contingent negative variation (CNV) and data of variational pulsometry (according to the measurements of R-R ECG intervals). Studies were carried out on 35 patients (group PD), 49 to 74 years old, with the stage of disease of 1.5 to 3.0 according to the Hoehn-Yahr international classification. In the course of CNV recording (i.e., in the state of a certain functional loading), we observed significant negative correlations between the integral magnitude (area) of this potential and indices of variational pulsometry (RMSSD, SDNN, C. var, and HF) that characterize the intensity of parasympathetic (respiratory) influences on the cardiovascular system. In the control group, such correlations were absent. We found significant correlations between the autonomic balance, CNV magnitude, and stage of PD reflecting the level of generalization of the pathological process. In the subgroup of patients with the PD stage 1.5 to 2.0, significant changes in the mean values of indices of parasympathetic influences during recording of the CNV were not observed, while in another subgroup (the PD stage 2.5 to 3.0), these values increased significantly (P < 0.05 and P < 0.01). If the estimates of the PD stage were low, the CNV area demonstrated greater values (P < 0.01). The disturbance of coordination of muscle-to-muscle interactions in the PD group is, probably, an important factor responsible for parasympathetic dysregulation and suppression of the CNV generation. We found positive correlation between the intensity of parasympathetic influences in the course of CNV recording and the level of postural disorders (r = 0.37, P < 0.05). On the contrary, the CNV magnitude demonstrated a negative correlation with the intensity of these disorders (r = −0.36, P < 0.05), as well as with the level of postural instability (r = −0.55, P < 0.001). We hypothesize that alterations of the autonomic balance and the activity of those cerebral structures, which are responsible for the motor readiness, result, to a significant extent, from weakening of the activity of the noradrenergic system due to degenerative processes developing in cells of the locus coeruleus. The impairment of the latter structure, together with degeneration of neurons of the substantia nigra and a decrease in the level of nigro-striatal dopamine, underlies the pathomorphological pattern of PD. Neirofiziologiya/Neurophysiology, Vol. 40, No. 3, pp. 242–253, May–June, 2008.  相似文献   
14.
The authors study by means of immunoperoxidase method the pattern of thyroglobulin, triiodothyronine and thyroxine distribution in 58 cases of thyroid disorders: 15 euthyroid goiters, 10 Graves' disease, 7 Hashimoto's thyroiditis, 11 folliculo-papillary carcinomas (6 primary tumors and 5 lymph node metastases), 8 follicular carcinomas, 4 anaplastic carcinomas and 3 medullary carcinomas. Thyroglobulin, triiodothyronine and thyroxine were present in most of the thyroid disorders, excepting anaplastic and medullary carcinomas. Thyroglobulin and thyroxine were localized both in the follicular epithelium and in the colloid, whereas triiodothyronine was present especially in the follicular cells. The thyroid hormones distribution in benign lesions is rather similar. In carcinomas, the pattern of thyroglobulin, triiodothyronine and thyroxine is more heterogeneous, but generally the triiodothyronine distribution is similar to that of thyroglobulin. In some carcinomas, triiodothyronine and thyroxine showed a weak or negative immunostaining. The immunoperoxidase method is a valuable tool in the study of functional disturbances in the thyroid pathology and in the diagnosis of thyroid carcinoma metastases as well. Positive thyroid hormones staining clearly indicates the thyroid origin of metastases.  相似文献   
15.
The study of the cell cycle of a yeast strain made it possible to define two parameters:T, the time elapsing between the appearance of two consecutive buds on a mother cell, and Θ, the time elapsing between the appearance of a bud and the beginning of the first mitotic cycle. The influence of these two parameters on the growth rate of the strain is studied.  相似文献   
16.
An antioxidant activity of the water-alcohol extracts of leaves of ten herbs from Western Siberia was studied. In vivo the capability of extracts to protect cells of Escherichia coli against the bacteriostatic action of H 2O2 and the influence of the extracts on the expression of the antioxidant gene katG coding catalase-hydroperoxidase I were investigated. In vitro the radical-binding activity with DPhPG· (1,1-diphenyl-2-picrylhydrazyl radical), the chelating capability with ferrozine, and total composition of flavonoids and tannins were determined. The extracts of Filipendula stepposa and Limonium gmelinii were characterized by the highest antioxidant activity. According to data, the test extracts could have an antioxidant effect on bacteria in different ways at once including the direct inhibition of ROS (reactive oxygen species), iron ion chelation and antioxidant gene induction.  相似文献   
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The fractionation of eukaryotic DNA by field inversion gel electrophoresis results in the appearance of discrete DNA-fragments. The set of these fragments is similar to that of different eukaryotic representatives and consists of various chromosomal DNAs, unified by size. The physical properties of DNA-fragments suggest that they can form multimeric structures due to the presence of sticky ends flanking discrete fragments. We suppose that the set of discrete DNA-fragments results in a specific cleavage of intact nuclear DNA and can reflect different levels of chromatin structural organization.  相似文献   
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