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241.
10 healthy men underwent a 48 hour acute hypobaric hypoxia in the "Taba?" climate chamber imitating conditions of an altitude of 4.00 m. above s.l. The "ascent" and "descent" took 30 minutes each. Blood and bone marrow samples were taken before entering the chamber and immediately after leaving it. A decrease in colony-forming capacity of granulo- and monocyte and fibroblast precursors was shown, along with an increase in functional activity of circulating monocytes and monocyte precursors in bone marrow. A possible role of changes in granulo- and monocytopoiesis and in stromal cells is discussed in relation to the increased morbidity and decreased cicatricial and bone tissue reparation in the mountains.  相似文献   
242.
Studies have been made of the effect of injections of hypothalamic nonapeptide neurohormone, arginine vasotocin, on functional condition of the interrenal gland in mature frogs. In unoperated, sham-operated and in animals 10 days after hypophysectomy, single and especially three subsequent injections of arginine vasotocin (5 x 10(-9) M per 1 kg of the body weight) result in evident activation of glandular cells of the interrenal gland which is manifested in the increase of the volume of their nuclei and cytoplasmic area, as well as in the dilatation of the blood vessels. Activation of the interrenal gland in hypophysectomized frogs, which lack endogenous ACTH, indicate the direct para-adenohypophyseal influences of nonapeptide hypothalamic hormones on the activity of glandular cells in the peripheral endocrine glands, in particular, the interrenal gland of the grass frog.  相似文献   
243.
Restriction assay of mtDNA has been made in 6 salmon species form the genus Oncorhynchus and one species from the related genus, i.e. Salvelinus malma. The size of the mitochondrial genome was found to be identical and equal to 16.7 kilobases. The digestion patterns of mtDNA cleaved by 5 restriction endonucleases (Eco RI, Bgl I, Bgl II, Hind III, and Pst I) were used for analysis of the levels of interspecific variation and for estimation the matrix of mtDNA sequence differentiation. It was found that the level of nucleotide sequence divergence (p) in the genus Oncorhynchus varies within 1.7-6.7%. Minimum p value was observed in a pair O. keta--O. gorbuscha, maximum one--between O. masu and other species. With respect to similarity in their mtDNA, three groups may be distinguished: 1) O. gorbuscha--O. keta; 2) O. nerka--O. kisutch, O. tschawytscha; 3) O. masu. Mean value of intergeneric level of sequence divergence between Oncorhynchus and Salvelinus was found to be equal to 8%. On the basis of mtDNA analysis, the dendrogram of similarity of the species was plotted which is consistent in principle with current viewpoints on phylogenetic relations among the Pacific salmon.  相似文献   
244.
Measurements of hemodynamics and blood metabolites in rats are often made by insertion of a small polyethylene (PE-50) catheter into the aorta via the carotid artery. Although the effect of this type of procedure on animal body weight has been described, little information exists regarding the quantitative and temporal effects of this procedure on liver and skeletal muscle glycogen concentration. Relative to the control group (group C), liver glycogen concentration was reduced by 56% 24 h after catheterization (group CN). With respect to liver glycogen concentration, it was apparent that a postcatheterization recovery period of variable duration (2-8 days; group CNR) based on attainment of a normal food consumption-to-body weight ratio (FdWt/BdWt) was more effective than was a fixed 6-day recovery period (group CN6). This was probably due to the large between-animal variability in recovery times required to reach normal FdWt/BdWt values. After aortic catheterization, FdWt/BdWt was a reasonable predictor of postprocedural liver (y = 2,601x + 43.9; r = 0.72; P less than 0.01) and diaphragm muscle glycogen concentration (y = 146.3x + 14.0; r = 0.57; P less than 0.05). Aortic catheterization did not affect the glycogen concentration in the other skeletal muscles examined. Since the results of certain types of experiments can be significantly influenced by liver glycogen concentration, the use of FdWt/BdWt on 24-h food intake as a general indicator of recovery after instrumentation via aortic catheterization is proposed.  相似文献   
245.
Goats were divided into three groups and given infusions of live Escherichia coli bacteria. Group I received no treatment, group II was treated with indomethacin (a cyclooxygenase inhibitor), and group III with dazoxiben (a thromboxane synthase inhibitor). Double indicator-dilution extravascular lung water (EVLW) in group I was significantly different from the treated groups. There was an early increase in EVLW in group I and group III but not in group II animals. At 6 h EVLW's in group I, group II, and group III were 100, 45, and 30% above base line, respectively. Lymph flow (QL) and lymph-to-plasma protein ratio (L/P) was not statistically different between groups. Estimated total fluid filtration [QL + d(EVLW)/dt] in group I and III was markedly elevated between 0 and 1.5-2 h after E. coli infusion. Cardiac output (QT) decreased to 40% of base line in group I, and it decreased slightly in group II because of the indomethacin but did not decrease after E. coli. QT decreased in group III but recovered more rapidly than group I. Mean pulmonary arterial pressure increased more rapidly in group I and reached a higher peak than either treated group. At 6 h these groups had similar pulmonary arterial and pulmonary arterial wedge pressures. We conclude that 1) indomethacin but not dazoxiben blocks the early increase in total fluid filtration after bacterial infusion, 2) dazoxiben does not prevent the increased endothelial permeability resulting from infusion of live bacteria, and 3) indomethacin may somewhat ameliorate the endothelial permeability change.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
246.
Dose-dependent progress of destructive processes (mitochondria destruction, proteolysis, autophagocytosis) is observed in HeLa cells treated with various concentrations of nickel (0.05-4 micrograms/ml) for 2, 4 and 24 hours. Parallel with it the compensation and adaptation responses of cells (increase of mitochondrion polymorphism, appearance of "macropolysomes", hypertrophy of the Golgi complex) take place.  相似文献   
247.
Dermatoglyphic+ of the nasal-lip speculum presents a complex structure of skin picture on its surface. Genetics and phenetics of this character permit determining different types of dermatoglyphics, their hereditary peculiarities to be retained in generations. Different types of dermatoglyphics are established to be preserved within genealogical lines and families of cows. Differences between breeds in some dermatoglyphic elements are observed.  相似文献   
248.
Cytosolic and mitochondrial pig heart aspartate aminotransferases (cAspAT and mAspAT) and chicken heart cAspAT have been oriented in a compressed slab of polyacrylamide gel and their linear dichroism LD spectra have been recorded. The coenzyme's tilt angles in the active sites of chicken cAspAT and pig mAspAT and their quasisubstrate complexes imitating catalytic intermediates have been computed. The computations are based on reduced linear dichroism values (delta A/A), the known directions of the transition dipole moments in the coenzyme ring and atomic coordinates of the coenzyme obtained by X-ray crystallography. It has been found that formation of the enzyme complex with glutarate and protonation of the internal pyridoxal-lysine aldimine induce reorientations of the coenzyme. As a result of protonation, the coenzyme ring tilts by 27 degrees in cAspAT and 13 degrees in mAspAT. Formation of the external aldimine with 2-methylaspartate is accompanied by tilting of the coenzyme ring by 44 degrees in cAspAT and 39 degrees in mAspAT. For the quinonoid complex with erythro-3-hydroxyaspartate, the tilt angles were found to be 63 degrees in cAspAT and 53 degrees in mAspAT. It is inferred that the basic features of the active site dynamics are similar in the three AspAT's studied. The differences in the coenzyme tilt angles between cAspAT and mAspAT may be linked to catalytic and structural peculiarities of the isoenzymes.  相似文献   
249.
1. Two forms of arginase were isolated from human erythrocytes; the main form adsorbed on CM-cellulose and the second form, occurring in much smaller amount, adsorbed on DEAE-cellulose. 2. The molecular weight of either arginase was 120,000 +/- 5000. 3. The erythrocyte arginases are similar in immunological properties to arginase A4 from human kidney and A2 from human liver, respectively. 4. Despite the literature data stating that human erythrocyte arginase and human liver arginase are identical, it was found that the main forms of arginase of these tissues A4 from erythrocytes and A5 from liver differ in immunological properties.  相似文献   
250.
We previously reported the clinical feasibility of a Phase I trial involving the topical administration of a RA gel applied cervicovaginally in women with mild or moderate cervical dysplasia. Now, we report hydrolysis and systemic absorption of the RA gel from the vagina. HPLC analysis of samples of residual gel obtained from the cervical canal after topical bolus application indicate that the RA undergoes prompt in vivo hydrolysis yielding retinol as a major metabolite. Venous blood samples of 41 subjects, who self-administered a RA gel, were analyzed for plasma retinol and RBP concentrations prior to and upon completion of a 7-day treatment course and upon return for follow-up examinations. An increase in both the concentrations of plasma retinol and RBP were detected after topical application of the RA gel. These elevated values receded after the gel administration was discontinued. No significant changes were observed in plasma retinol or RBP concentrations in placebo-treated subjects. The efficacy of RA as a chemopreventive agent in treating cervical dysplasias remains to be determined.  相似文献   
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