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1.
Using a model of “bony tissue tunnel defect” produced by the removal of a mandibular incisor in rats, it was found that closing the defect with a bioprosthesis prevented the washing out of osteogenic bone marrow precursor cells, which serve as a substrate for reparative osteogenesis, from the mandibular spongy bone. The reparative process was strongly stimulated if the bioprosthesis contained estrone; in this case, the time required for the tooth socket to be filled with osteogenic tissue was shortened by half. When no bone marrow elements were present in the socket, it was filled with fibrotic connective tissue, the number of bone marrow elements in spongy bone cavities was small, and the mandibular osteogenic tissue underwent atrophy. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N o 1, pp. 72–75, January, 1995  相似文献   

2.
The relative capacity of substances of the pentarane group for binding with progesterone receptors of the plasma membranes of uterine cells of oophorectomized rats is studied. Introduction of an extra carbocycle D' in the progesterone molecule at the 16α and 17α sites and further modification of the molecule cause an increase of the relative binding capacity of these compounds. Analysis of the findings identifies substance III, showing the highest activity toward all the discussed parameters and a promising candidate for further preclinical studies. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol., 118, N o 7, pp. 31–32, July, 1994  相似文献   

3.
Cytosolic and plasma membrane receptors for progesterone and estradiol are studied in myomatous nodes (MN) and in histologically unaltered myometrium (HUM) against the background of myoma. The level of cytosolic receptors for both hormones is higher in the myoma cells than in the essentially healthy myometrium. In the plasma membranes the progresterone reception is reduced and the estradiol reception is unchanged compared with HUM. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N o 7, pp. 33–34, July, 1994  相似文献   

4.
In the plasma membranes of cardiac myocytes from old rats, Na, K-ATPase activity and phosphatidylinositol levels were lower and cardiolipin levels higher than in those from younger (adult) animals. Insulin injected into adult rats elevated Na, K-ATPase activity and phosphatidylethanolarnine levels and caused a sharp fall in phosphatidylinositol levels. In old rats, insulin had no effect on Na, K-ATPase activity, but lowered phosphatidylethanolamine levels. In experiments with cellular hybrids (cytosol+plasma membranes), cytosol from adult rats activated Na, K-ATPase in both adult and old rats, whereas cytosol from old rats failed to activate the enzyme both in old and in adult rats. Actinomycin D prevented the stimulatory effect of insulin on Na,K-ATPase activity. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N o 8, pp. 122–125, August, 1995  相似文献   

5.
NO synthase activity and the generation of reactive oxygen species (ROS) were measured in different brain regions of old rats separated in an “emotional resonance” test into two groups: passive rats (those preferring a dark space) and active ones (those preferring a lighted space). In both groups, NO synthase activity and ROS generation were at the highest level in the cerebellum. In the tested brain regions of active rats, NO synthase activity was lower and ROS generation more strongly marked than in the respective regions of passive rats. Interregional positive linear correlations were discovered both for NO synthase activity and for ROS generation. When the two groups were considered together, negative correlations were detected between NO synthase activity and ROS generation. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N o 8, pp. 145–147, August, 1995 Presented by I. P. Ashmarin, Member of the Russian Academy of Medical Sciences  相似文献   

6.
Vascular spasm, hypertrophy of cardiac muscle cells, and necrotic changes in the myocardial tissue of rats administered norepinephrine in incremental doses over 14 days were accompanied by a considerable activation of lipid peroxidation and a weakening of antioxidant defense during the first 7 days of exposure to this injurious agent. On day 14, despite the greatly increased load of norepinephrine, the concentrations of lipid peroxidation products and the activity of antioxidant enzymes deviated from their control values to a lesser extent than on day 7. A similar change was shown by the concentration of brain tissue phosphatidylinositol-4,5-diphosphate, a source of second messengers, suggesting that the phosphoinositide system of second messengers is involved in the mechanisms whereby the destructive effects of norepinephrine are mitigated. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N o 8, pp. 137–139, August, 1995 Presented by I. P. Ashmarin, Member of the Russian Academy of Medical Sciences  相似文献   

7.
Cat and rat experiments show that the protein fraction isolated from blood serum of the Greenland seal has a protective activity against motion sickness. This activity is comparable to that of the classical vestibuloprotector scopolamine and is greater than that of diprazine. Radioligand assay of the receptor binding showed that the serum protein fraction has the highest affinity for α2-adrenoceptors, μ-opioid, and benzodiazepine receptors. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol 117, N o 4, pp. 444–445, April, 1994  相似文献   

8.
Differences in3H-aldosterone binding with hippocampus cytosol receptors were found to be dependent on the behavioral type of male Wistar rats in the “emotional resonance” test. These differences were not observed in the cytosol analysis of the remaining part of the brain. Control rats and rats subjected to short-term stress by painful electrical stimulation showed a long-term drop of3H-aldosterone binding with hippocampus cytosol in active as compared to passive animals preferring a closed space. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N o 7, pp. 49–51, July, 1995 Presented by I. P. Ashmarin, Member of the Russian Academy of Medical Sciences  相似文献   

9.
The morphology of tissue elements of human ovarian follicles was studied in the course of normal folliculogenesis and in some forms of its disorders. Signs of abnormal development of follicles were detected that are typical of different stages of their development under the conditions studied. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N o 8, pp. 188–191, August, 1995  相似文献   

10.
After a prolonged (for 30 days) adaptation of rats to intermittent hypoxia, their brains contained lowered levels of mitochondrial cytochromes, despite an increase in the number of mitochondria in the brain tissue mass, along with similar levels of high-energy compounds and more protein as compaired to the brains of unadapted controls. A mitochondrial population with novel properties presumably emerged in the brain. These effects were all more strongly marked in rats with an initially low resistance to hypoxia. In the liver of hypoxiaadapted animals, unlike in their brain, cytochrome levels in the mitochondrial and microsomal redox chains were lowered and the biogenesis of mitochondria was much less intensive. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N o 12, pp. 576–579, December, 1995  相似文献   

11.
Effects of prednisolone, estradiol, and testosterone on the transport of Ca2+ and the respiration induced by it in the heart and liver mitochondria of rats were studied. Prednisolone and testosterone were found to reduce the Ca-accumulating capacity of the mitochondria, the rates of ion entry and exit, and the rate of Ca2+-induced respiration. Estradiol, while inhibiting Ca2+ transport across mitochondrial membrane, did not influence the respiration in the phase of Ca2+ absorption, but accelerated it in the phase of ion exit. These data suggest that due to their lipophilic properties, the steroids become incorporated in the mitochondrial membrane, thereby changing its viscosity and permeability and limiting the mobility of transmitter proteins. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N o 12, pp. 616–618, December, 1994  相似文献   

12.
The effects of chronic administration of melipramine on the development of behavioral signs of depression in rats are studied using the model of a depressive syndrome induced by systemic administration of MPTP. Preadministration of melipramine prevents such MPTP-induced behavioral signs of depression in rats as decreased motor activity, reduced total daily liquid intake, reduced preference of sucrose solution over water, and increased depression index. Translated fromByulleten' Eksperimental'noi Giologii i Meditsiny, Vol. 120, N o . 8, pp. 160–163, August, 1995  相似文献   

13.
Changes in the spectrum of hepatic histones characteristic of active chromatin were observed in rats as early as 3 h after partial hepatectomy. At 6–9 h postsurgery, acridine orange binding to deproteinized chromatin areas was considerably increased. At 13 h the histone spectrum of liver cells from operated rats did not differ from that of control samples from sham-operated animals. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N o 4, pp. 369–371, April, 1995  相似文献   

14.
Selective agonists 5-HT1A of serotonin receptors (8-OH-DPAT and flezinoxan) had an inhibitory effect on the manifestation of hereditary catalepsy in mice and rats. No differences were revealed in specific binding of3H-8-OH-DPAT to 5-HT1A receptors in the striatum of either cataleptic or noncataleptic mice and rats. Nonetheless, an increase of the density of these receptors was observed in the frontal cortex of CBA mice predisposed to catalepsy in comparison with mice of the noncataleptic C57Bl strain. The data indicate a contribution of 5-HT1A receptors to the regulation of hereditary catalepsy. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N o 12, pp. 633–635, December, 1994 Presented by V. P. Kaznacheev, Member of the Russian Academy of Medical Sciences  相似文献   

15.
It is shown on rats that intravenous administration of theNeisseria menignitidis lipopolysaccharide lowers the mean arterial pressure, myocardial contractility and vascular tone in the system of the left carotid artery. In rats exposed to gamma radiation and then to the lipopolysaccharide, the decrease in myocardial contractility and the degree of arterial hypotension were more pronounced than in those exposed to the lipopolysaccharide alone, but the vascular tone in the carotid artery system was reduced to a lesser extent. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N o 8, pp. 129–131, August, 1995 Presented by V. A. Matyukhin, Member of the Russian Academy of Medical Sciences  相似文献   

16.
The activity of aromatase (estrogen synthetase) in tumor tissue of breast cancer patients was investigated by biochemical and immunohistochemical methods. The detection of medium or high enzyme activity in tumor tissue was virtually the same for both methods. According to immunohistochemical analysis, aromatase activity was localized mainly in malignant epithelial cells, being reliably higher in the tumors of patients in menopause than in those whose cycle was intact. Doubts about the biological role of aromatase in breast cancer tissue may be dispelled if the tissue topography of the enzyme and the individual ratio of epithelial to stromal cellular elements in individual neoplasms of the breast are taken into account. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N o 10, pp. 410–413, October, 1995 Presented by A. N. Klimov, Member of the Russian Academy of Medical Sciences  相似文献   

17.
The antibiotic benzylpenicillin was found to produce dose-dependent antiulcerogenic effects in rats when administered immediately before their exposure to acute stress (swimming for 1 h) that led to gastric mucosal ulceration. Such effects were not observed in rats given benzylpenicillin 48 h before stress exposure. The results of this study suggest that in acutely stressed animals benzylpenicillin may activate as yet unidentified mechanisms which afford protection to the gastric mucosa and which are not associated with the longer-lasting antimicrobial effects of this antibiotic. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N o 8, pp. 131–133, August, 1994  相似文献   

18.
The development of bronchospasm is shown to be accompanied by lipid peroxidation (LPO) activation; 3-fold and 8-fold rises of malondialdehyde concentration are found in homogenate of lung from sensitized animals and from animals provoked with egg albumin antigen, respectively. The use of luminol-dependent chemiluminescence (CL) reveals that in sensitized rats the production of oxygen free radicals is increased by alveolar macrophages activated with phorbol myristate acetate. Troventol at 10−3 mg/ml inhibits the CL response of phagocytes both in intact and in sensitized rats and lowers the level of Fe2+-induced LPO in lung tissue but not in the liver of intact animals. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N o 6, pp. 619–621, June, 1994  相似文献   

19.
The metabolism of sialoglycoproteins and ganglioside (free, oligo-, protein-, and lipid-bound sialic acids, and activity of sialidase) is studied in plasma and gastric and duodenal mucosa of rats subjected to immobilization stress for 8 days. Sustained alterations in these parameters are found in severely stressed animals. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N o 9, pp. 268–269, September, 1994 Presented by S. S. Debov, Member of the Russian Academy of Medical Sciences.  相似文献   

20.
A chick embryo homogenate inhibited the growth and metastatic spread of Pliss sarcoma in rats and prolonged their survival. The histological picture of extensive tumor tissue necrosis with a characteristic infiltration by leukocytes and macrophages suggests that the mechanism underlying the antineoplastic action of the embryonal homogenate is quite different from that of cyclophosphamide and involves the activation of cell-mediated immunity. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N o 12, pp. 610–612, December, 1995  相似文献   

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