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101.
NM Nasybullina VP Zherdev VI Gunar VM Kopelevich GS Kozlova 《Canadian Metallurgical Quarterly》1997,60(6):52-54
The authors studied the permeability of the blood-brain barrier (CEB) to two nootropics: calcium ketogomopantothenate (KRA-Ca), a GABA derivative, and and calcium salt of oxybutyrate (OB-Ca), a derivative of GOBA. It was established that both preparations penetrate the CEB easily and are found in the brain at different intervals after their administration. However, essential differences in the distribution constant of these drugs were disclosed: KPA-Ca permeated the CEB more intensively and was accumulated in larger amounts in the late-term intervals. 相似文献
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The induction of complex bilateral leg muscle activation combined with coordinated stepping movements is demonstrated in patients with complete paraplegia. This was achieved by partially unloading patients who were on a moving treadmill. In comparison to healthy subjects, the paraplegic patients displayed a less dynamic mode of muscle activation. In all other respects leg muscle electromyographic activity was modulated in a similar manner to that in healthy subjects. However, the level of electromyographic activity in the gastrocnemius (the main antigravity muscle during gait) was considerably lower in the patients. During the course of a daily locomotor training program, the amplitude of gastrocnemius electromyographic activity increased significantly during the stance phase, while inappropriate tibialis anterior activation decreased. Incompletely paraplegic patients benefited from the training with respect to performance of unsupported stepping movements on solid ground. In about half of completely paraplegic patients with low muscle tone, no beneficial effect of the training was seen. This may be due to an inhibitory effect on spinal neuronal activity by drugs patients were taking (e.g., prazosin, clonidine, cannabinoids). In this study intrathecal application of clonidine drastically reduced, while epinephrine enhanced locomotor muscle electromyographic activity. The results of this study promise to be significant in the treatment of paraplegic patients. 相似文献
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IM Spivak NM Pleskach VM Mikhel'son D Bootsma A Kolman 《Canadian Metallurgical Quarterly》1997,39(6):420-434
The action of ionizing radiation and chemical mutagens--epoxides (ethylene oxide, propylene oxide, epichlorohydrin)--upon survival and repair processes in xeroderma pigmentosum (XP2SP) and Cockayne syndrome (CS1SP) patients' cells was studied, compared to healthy donor's cells VH-10 and C5RO. Ionizing radiation was demonstrated to enhance significantly higher survival decrease of XP2SP and CS1SP fibroblasts, compared to healthy donor's cells, according to the cloning efficiency criterion. In contrast to this, no significant difference between XP2SP and healthy donor's cells was found, according to cells' ability to replicative DNA synthesis after gamma irradiation. Differences in survival of mutant cells and healthy donor's cells after treatment by epoxides were found significant only following XP2SP being treated by ethylene oxide. DNA single-string breaks in XP2SP and in CS1SP cells treated by mutagens studied were proved to occur with the same frequency as in the DNA of the control cells; however the DNA repair according to this criterion was significantly suppressed in mutant cells. 相似文献
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One hundred patients showed signs and symptoms of temporomandibular joint disorder, were participated in a one year follow up study. The patients were randomly divided into four groups: Acuhealth treatment (group A), occlusal splint therapy (group B), Acuhealth and occlusal splint therapy (group C), and control (group D). Each group comprised 25 patients. The patients were examined before and 3, 6, and 12 months after treatment. At the three month evaluation, the patients who were not satisfied with the treatment outcome were offered additional treatment. The result showed that 87% of the patients treated by Acuhealth unit, 77.3% of the patients treated with occlusal splint therapy, and 91.3% of the patients received Acuhealth and occlusal splint therapy were improved subjectively and clinically after 3 months follow-up. The patients who responded well to treatment initially also responded well in the long run. The study showed that the Acuhealth unit proved to be an ideal early therapy for TMD, and complemented later with occlusal splint. 相似文献
109.
Crystallographic studies of a number of aminoacyl-tRNA synthetases and their complexes with ATP, amino acid and cognate tRNA are leading to an increasingly detailed picture of how these sophisticated enzymes function. Within the two distinct structural classes of ten synthetases, many common features are apparent, although evolution has led to many interesting idiosyncrasies in certain enzymes. Recent advances, specifically concerning class II enzymes, have increased our knowledge of both the role of electrophiles in the mechanism of amino acid activation and cross-subunit tRNA recognition and help solve the evolutionary puzzles that have emerged from the extension of the aminoacyl-tRNA synthetase database to include Archae. 相似文献
110.
TV Nasedkina AE Kuz'minova SA Surkov NM Pleskach VV Prokof'eva IM Spivak VM Mikhel'son AI Poletaev 《Canadian Metallurgical Quarterly》1997,39(9):809-821
Lymphoblastoid cell lines from patients with xeroderma pigmentosum (2 forms) and progeria (unusual form) were established using transformation of peripheral blood lymphocytes by Epstein--Barr virus. The influence of different UV doses on cell vitality, proliferation and cell cycle progression was studied by means of flow cytometry. The cell vitality was determined after incubation of cells with etidium bromide and FDA. We used cytograms with two logarithmic signals (log green/log red) to discriminate the cell cycle status. Cell cultures were used with density of 500,000 cells per 1 ml, previously synchronized at G-phase by the incubation in a medium with low serum content. The effect of UV irradiation was followed during 72 h. Among four analysed cell lines only line XP2SP demonstrated enhanced UV sensitivity, expressed by decreasing of the amount of living cells after the UV dose of 2.5 J/m2 and higher. The cell cycle studies showed that cells were blocked in S-phase and simultaneously the amount of apoptotic cells with both reduced DNA content and ability to bind FDA was seen increased. Similar events were observed in the control line only after the dose of 20 J/m2 and higher. 相似文献