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Intoxication with bacterial lipopolysaccharide (endotoxin) is accompanied by considerable rearrangements in the systems of blood microcirculation and water metabolism of the liver. These rearrangements are manifested as increased sinusoid area, changed total area of the cytoplasm and nuclei as well as the nucleocytoplasmic ratio in hepatocytes, increased content of total water in the organ, and changed magnetic relaxation properties (spin-lattice and spin-spin relaxation times). Preliminary parasympathetic denervation of the liver (vagotomy) changes the pattern of the organ response to bacterial endotoxin poisoning as indicated by the kinetics of studied morphological and biophysical parameters.  相似文献   
3.
EEG correlates of two main effects of long-term hyperventilation (cyclic breathing similar to rebirthing), namely, psychotic manifestations and sensations in internal organs, are considered. Standard EEGs of 44 subjects were recorded and subsequently treated by multiparametric methods. It was shown that, in the case of psychotic phenomena (hallucinations, visual and auditory images, different scenes, virtual travels, out-of-body experiences, etc.), the changes in the spatial organization of bioelectric potentials as compared with the baseline have different patterns than in the case of sensations in internal organs. The changes are observed in the frontal regions of the cortex: a decrease in spatial synchronization (linear processes) during an increase in spatial disarray (nonlinear processes) of bioelectric potentials and the intensifying of high-frequency β activity. If sensations in internal organs appear, a decrease in the above parameters was observed in the right hemisphere and in posterior cortical areas. The data are discussed from the viewpoint of qualitative specificity of changes in functional states during an altered state of consciousness with manifestations of different psychovisceral phenomena.  相似文献   
4.
Mucosal candidosis was induced in CBA mice by intraoral inoculation following treatment with corticosteroid-containing aerosol (beclomethasone dipropionate). Histologically, in hormone treated mice the adherence of the pathogen to the mucosal surface was found during the first hours after inoculation. This is followed by the formation of the germ tubes and invasion in the epithelial layer. Pseudomycelial invasion in the malpighian layer is accompanied by the leukocyte response that limits the further spread of the fungal cells. In intact mice, the inoculation is not followed by the effective attachment of the fungal cells to the mucosal surface and induction of mycotic lesions. In vitro experiments have demonstrated the enhanced adherence of fungal blastospores to the epithelial cells of the hormone treated animals, that appears to be one of the mechanisms in the pathogenesis of candidosis in these animals.  相似文献   
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A variety of data support the existence of an opioid receptor complex composed of distinct but interacting mu cx and delta cx binding sites, where "cx" indicates "in the complex." The ability of subantinociceptive doses of [Leu5]enkephalin and [Met5]enkephalin to potentiate and attenuate morphine-induced antinociception, respectively, is thought to be mediated via their binding to the delta cx binding site. [D-Pen2,D-Pen5]Enkephalin also modulates morphine-induced antinociception, but has very low affinity for the delta cx binding site in vitro. In the present study, membranes were depleted of their delta ncx binding sites by pretreatment with the site-directed acylating agent, (3S,4S)-(+)-trans-N-[1-[2-(4-isothiocyanato)phenyl)-ethyl]-3-methy l-4- piperidyl]-N-phenylpropaneamide hydrochloride, which permits selective labeling of the delta cx binding site with [3H][D-Ala2,D-Leu5]enkephalin. The major findings of this study are that with this preparation of rat brain membranes: a) there are striking differences between the delta cx and mu binding sites; and b) both [D-Pen2,D-Pen5]enkephalin and [D-Pen2,L-Pen5]enkephalin exhibit high affinity for the delta cx binding site.  相似文献   
7.
The area of the section of presynaptic dense projections of the active zone of axondendritic synapses of the rat's cortex was measured using a television complex. Tissue specimens were contrasted with phosphotungstic acid. Morphometry was carried out in the regime of error correction in measurement, the errors arising in scanning process of image. The area of the section of mitochondria, lysosome, nucleoli, channels and tanks of the endoplasmic reticulum may be measured by the method suggested. Quantitative data, obtained by the morphometry of the synapse ultrastructure, may serve a basis for understanding the mechanism by which synapses are involved in information processes of the central nervous system.  相似文献   
8.
The location of major quantitative trait loci (QTL) contributing to stem and leaf [Na+] and [K+] was previously reported in chromosome 7 using two connected populations of recombinant inbred lines (RILs) of tomato. HKT1;1 and HKT1;2, two tomato Na+‐selective class I‐HKT transporters, were found to be closely linked, where the maximum logarithm of odds (LOD) score for these QTLs located. When a chromosome 7 linkage map based on 278 single‐nucleotide polymorphisms (SNPs) was used, the maximum LOD score position was only 35 kb from HKT1;1 and HKT1;2. Their expression patterns and phenotypic effects were further investigated in two near‐isogenic lines (NILs): 157‐14 (double homozygote for the cheesmaniae alleles) and 157‐17 (double homozygote for the lycopersicum alleles). The expression pattern for the HKT1;1 and HKT1;2 alleles was complex, possibly because of differences in their promoter sequences. High salinity had very little effect on root dry and fresh weight and consequently on the plant dry weight of NIL 157‐14 in comparison with 157‐17. A significant difference between NILs was also found for [K+] and the [Na+]/[K+] ratio in leaf and stem but not for [Na+] arising a disagreement with the corresponding RIL population. Their association with leaf [Na+] and salt tolerance in tomato is also discussed.  相似文献   
9.

Background  

Existing cut-offs for fasting plasma glucose (FPG) and post-load glucose (2hPG) criteria are not equivalent in the diagnosis of diabetes and glucose intolerance. Adjusting cut-offs of single measurements have not helped so we undertook this project to see if they could be complementary.  相似文献   
10.
Wine vinegar is a product obtained from wine acidification which contains at least 5% by wt. of acetic acid, in general without any additives or colorings.
Aspects studied in this work include: the determination of the taste group thresholds (geometric mean of the individual best-estimate thresholds "BET") of two different acids (citric and acetic acids) in aqueous solution and spanish vinegars produced from table and sherry wines. The results obtained suggest that wine vinegar can be considered something more than just an acidulant agent.
In order to evaluate differences among wine vinegars, discriminant tests for twenty-five spanish vinegars (sherry, table and flavored vinegars) were applied. Six of the twelve attributes freely chosen by assessors allowed grouping of the spanish wine vinegars according to their sensory aspects.  相似文献   
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