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861.
VF Antoniv PV Kovalyk VI Zhuravlev NV Kolodi? IM Prokopiv 《Canadian Metallurgical Quarterly》1993,(4):12-16
Topographic anatomical guide points were studied on 126 total preparations of the temporal bones. The relation of the temporal bone pyramid angles in sagittal and horizontal planes, the distance from spina suprameatum to the pyramid top, from spina suprameatum to promontorium, from promontorium to internal carotid artery with the shape of the skull has been established. 相似文献
862.
LS Kolesnichenko VI Kulinski? MV Ias'ko EN Ekimov LM Stanevich EF Glushkova SB Belogorov GT Filippova 《Canadian Metallurgical Quarterly》1994,40(5):10-12
The stress activates glutathione peroxidase in the heart, liver, and kidney, glutathione transferase in the heart and liver, inhibits gamma-glutamyl transferase in the liver; the activity of glutathione reductase and the content of reduced glutathione were unchanged. Two-four-minute hypercapnic hypoxia unchanged the activity of glutathione metabolic enzymes. The activity of the above enzymes decreases in some organs at the death caused by 2-15-minute hypoxia. Long-term intermittent adaptation to hypobaric hypoxia lowers the activity of glutathione peroxidase, -transferase and -reductase. The biological value of the two types of enzymatic responses may be different: stress-induced activation of glutathione metabolic enzymes can enhance resistance to stress and xenobiotics; however, their inhibition during hypoxic adaptation may produce the opposite effect. 相似文献
863.
VV Poliakov SM Ivanova VB Noskov OI Labetskaia IuV Iarlykova VV Karashtin VI Legen'kov TG Sarycheva ZG Shishkanova GI Kozinets 《Canadian Metallurgical Quarterly》1998,32(2):9-18
In the nearly 15-month mission aboard MIR the cosmonaut-physician and members of three crews (MIR-15, -16, and -17) carried out a program of hematological investigations. Most of the changes related to the red blood system and included reduction in hemoglobin and hematocrit. Erythrocytes had decreased concentration and took on abnormal forms. There were also signs of altered metabolism of erythrocytes. Of interest are phase-by-phase variations in the levels of erythrocytes in the course of long-term stay in microgravity, and absence of a convincing correlation between hemoglobin, erythrocyte and hematocrit levels. But for lymphocytosis that returned to the norm already on the first day of recovery, no material changes occurred to the leukocyte profile. Investigations at the landing site displayed erythropenia, decreased reticulocytes and ensuing reticulocyte reaction, and gradual regain of the erythrocyte number that can be viewed as a normal physiological reaction of the blood system to the set of factors of spaceflight and early readaptation. Besides, the investigations showed a large individually of blood reactions to prolonged stay in space flight. 相似文献
864.
Combination of the Q beta replicase reaction with the Escherichia coli cell-free translation system markedly enhances replication of a recombinant RQ-DHFR RNA consisting of the dihydrofolate reductase (DHFR) mRNA sequence inserted into RQ135(-1) RNA, an efficient naturally occurring Q beta replicase template. The enhancement is associated with a replication asymmetry previously described for the replication of Q beta phage RNA in vivo; the sense (+)-strands are produced in large excess over the antisense (-)-strands. This, in turn, results in increased synthesis of the functionally active DHFR. These effects are not observed when DHFR mRNAs or RQ135(-1) RNAs are used as templates, if the translation system is not complete, or if it is inhibited by puromycin. The coupled replication-translation of nonviral mRNA recombinants can serve as a useful model for studying the fundamental aspects of virus amplification and can be implemented for large-scale protein synthesis in vitro. 相似文献
865.
866.
AO Kumerova VI Petukhov AP Shkesters AA Silova AG Letse 《Canadian Metallurgical Quarterly》1996,42(2):144-147
Induction of tolerance to fully major histocompatibility complex (MHC)-mismatched rat islet allografts implanted at two different islet transplant sites (liver and kidney capsule [KC]) was examined. Streptozotocin-induced diabetic Lewis (RT1(1)) rats remained hyperglycemic (> 200 mg/dl) after intrahepatic preimmunization by injection of 200 low-temperature cultured (24 degrees C for 7 days) Wistar-Furth (WF, RT1u) rat islets into the portal vein with one injection (1 ml) of rat antilymphocyte serum intraperitoneally. Three weeks later, 1,200 WF islets that had been cultured to remove passenger lymphoid cells were transplanted into the liver via the portal vein or under the KC. The intrahepatic transplants survived 60.2 +/- 11.9 days, and all six of the KC transplants maintained normoglycemia for > 100 days after the preimmunization regimen. In contrast, survival of fresh islet transplants was not significantly improved by this preimmunization protocol at either transplantation site. This study demonstrates that indefinite islet allograft survival can be achieved across a full MHC mismatch by intrahepatic preimmunization with a small number of cultured donor islets and a brief period of immunosuppression followed by transplantation of low-temperature cultured donor islets. 相似文献
867.
868.
869.
AP Simonenkov VI Smirnova VN Iakovenko AA Zviagin VB Gel'fand SA Orudzheva LS Makhmudova 《Canadian Metallurgical Quarterly》1998,(12):38-41
In 26 patients (female 11, males--15) with diabetic angiopathy (necrosis of the foot or toes) local measurement of pO2 by transcutaneous mode was carried out before and during introduction of serotonine adipinate. Simultaneously with evaluation of pO2 in 14 patients electromyography (EMG) was made. Serotonine adipinate was introduced intravenously with a speed of 5.0-10.0 mg per hour. In this group mean age of the patients made up 57.4 years, mean values of initial pO2 25.6 mm Hg, and mean indices of pO2 at the moment of serotonine treatment 38.5 mm Hg. Average increase of pO2 during serotonine infusion was registered as 50.4% in comparison with mean initial data. In all 14 patients, who underwent simultaneous measurement of pO2 and registration of EMG, reinforcement of electrical activity of smooth muscles (SM) of various intensity and increase in tissue pO2 were detected. Improvement of microcirculation (increase of transcutaneous pO2, reinforcement of electrical activity of SM as a result of serotonine introduction) evidences that functional and morphological changes of serotonine receptors of SM are involead in genesis of diabetic angiopathy. The data obtained showed that in diabetes mellitus, besides insulin deficiency, insufficiency of such an endogenous factor as serotonine duclops. Thus, serotonin should be used for prophylaxis and treatment of diabetic angiopathies. 相似文献
870.