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941.
CT and roentgenography were used for the investigation of 78 patients with the radicular syndrome. The state of the intervertebral disks, intervertebral joints and cerebrospinal canal in degenerative vertebral diseases was assessed. CT permits the detection of hernia, protrusion of the intervertebral disks, deformity of the intervertebral joints, and the narrowing of the cerebrospinal canal as a result of degenerative changes, as well as establishing the cause of the affection of neural structures in the cerebrospinal canal, radicular holes. CT possesses some advantages over roentgenography in the diagnosis of degenerative vertebral diseases and can be recommended as the principal method together with roentgenography for investigation of patients with lumbar pains. 相似文献
942.
Effects of moderate (42 degrees C, 1 hour) and strong (44 degrees C, 1 hour) heat shocks on resting (TR) and phytohemagglutinin stimulated human T-cells (TP) were studied. Both treatments were shown to cause in the latter considerable fall of the level of protein synthesis, as compared to resting cells. Mitogen-stimulated cells stopped their proliferation irreversibly and part of them (approx: 40%) died after even mild shock (at 42 degrees C). Following heat treatment in both the cell types the synthesis of heat shock 70 and 90 kDa proteins was induced which was much more pronounced in TR. These and earlier results of the authors allow a conclusion that involvement of cells in active proliferation may decrease their resistance to stress, and that this phenomenon coincides with the diminishing in synthesis and accumulation of stress proteins. 相似文献
943.
M. D. Sacristán M. Gerdemann-Knörck O. Schieder 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1989,78(2):194-200
Summary With the idea to develop a selection system for asymmetric somatic hybrids between oilseed rape (Brassica napus) and black mustard (B. nigra), the marker gene hygromycin resistance was introduced in this last species by protoplast transformation with the disarmed Agrobacterium tumefaciens strain C58 pGV 3850 HPT. The B. nigra lines used for transformation had been previously selected for resistance to two important rape pathogens (Phoma lingam, Plasmodiophora brassicae). Asymmetric somatic hybrids were obtained through fusion of X-ray irradiated (mitotically inactivated) B. nigra protoplasts from transformed lines as donor with intact protoplasts of B. napus, using the hygromycin resistance as selection marker for fusion products. The somatic hybrids hitherto obtained expressed both hygromycin phosphotransferase and nopaline synthase genes. Previous experience with other plant species had demonstrated that besides the T-DNA, other genes of the donor genome can be co-transferred. In this way, the produced hybrids constitute a valuable material for studying the possibility to transfer agronomically relevant characters — in our case, diseases resistances — through asymmetric protoplast fusion. 相似文献
944.
A J Barwijuk K Swietochowska R Pia?cik K Jaroszewicz Z Skrzydlewski 《Acta physiologica Polonica》1989,40(4):404-408
The total phospholipids and their various classes in erythrocytes and blood plasma were determined quantitatively by means of two-dimensional thin-layer chromatography. The total amount of phospholipids in neonate plasma was approximately half of that found in adult plasma, however, the amount of phospholipids in erythrocytes of the neonate was significantly higher. The differences were observed in some classes of phospholipids in the plasma and erythrocytes of neonates as well as adult human beings. 相似文献
945.
Andrew A. Lackner Morten Schidt Gary C. Armitage Peter F. Moore Robert J. Munn Preston A. Marx Murray B. Gardner Linda J. Lowenstine 《Journal of medical primatology》1989,18(3-4):195-207
Simian acquired immune deficiency syndrome (SAIDS) caused by the type D retrovirus SRV-1 results in opportunistic infections and a spectrum of oral lesions similar to those seen in humans with AIDS. To better understand the pathogenesis of these oral lesions we have retrospectively examined the oral mucosa from ten rhesus monkeys that died with SAIDS and prospectively examined the oral mucosa of ten additional animals inoculated with SRV-1 to determine at what time, and in what cells SRV-1 infection of the oral mucosa occurs. Using single and double label immunohistologic techniques, and electron microscopy we detected SRV-1 in clusters of oral epithelial cells and rare Langerhans cells as early as 1 month postinoculation. 相似文献
946.
M Cervantes R Ruelas R Sánchez G Alvarez-Reséndiz 《Boletín de estudios médicos y biológicos》1989,37(1-2):17-27
The effects of alphaxalone-alphadolone acetate (27.07 microM/kg-7.68 microM/kg) on neurologic injury following acute cerebral ischemia induced by an 8 min cardiorespiratory arrest (CRA) were investigated in cats through the analysis of neurological deficit scores and brain electrical activity; i.e., electroencephalogram (EEG) from parieto-occipital cortices and EEG and multiunit activity (MUA) from mesencephalic reticular formation (MRF). The CRA resulted from electrically induced cardiac arrest and stopping of mechanical ventilation in paralyzed cats which were successfully resuscitated within the immediate 4 min after the end of CRA. Two groups of cats were studied: I. Untreated, which received saline iv; II. Treated, which received alphaxalone-alphadolone acetate iv, 7-9 min after the end of CRA. Neuromuscular blockade and mechanical ventilation were maintained until 8 h following the CRA; then the cats were allowed to recover spontaneous respiratory activity. EEG phenomena were different in untreated and treated cats during this immediate post-arrest period. The former showed rhythmic bursts of fast (12-20 Hz) EEG activity at 1-2 sec intervals from 15-20 min until 3-4 h after the CRA, abundant spikes and delta-like waves. By contrast, administration of alphaxalone-alphadolone acetate resulted in burst suppression EEG pattern during 1 h. Progressive recovery of background EEG activity occurred afterwards. MUA from MRF disappeared during the CRA, however 6 h later the mean MUA frequency in untreated cats ranged between 32-46% and in treated cats 18-27% of their control mean frequencies during paradoxical sleep (100%). Daily electrographic records were performed in all the cats during quiet attentive behavior at each of the five days following the CRA. Significant differences were found in the frequency distributions of MUA from MRF (1st day, p less than 0.01; 5th day, p less than 0.01) as well as in the cortical EEG waves (1st day, p less than 0.01; 5th day, p less than 0.05) before and after the CRA in the untreated group. A wide dispersion of MUA values, and increased proportions of delta and theta-like waves and spindle bursts, besides a significantly high (p less than 0.001) number of spikes occurred in these EEG records the days following the CRA. The frequency distributions of MUA and EEG did not significantly differ before and after the CRA in the treated group; however, a significantly high (p less than 0.05) number of spikes was found in treated cats following the CRA.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
947.
Trypanosoma cruzi: identification of specific epimastigote antigens by human immune sera 总被引:2,自引:0,他引:2
M G Morgado J Ivo-dos-Santos R T Pinho E Argüelles J M Rezende B Galv?o-Castro 《Memórias do Instituto Oswaldo Cruz》1989,84(3):309-314
Soluble antigens from epimastigotes of Trypanosoma cruzi were analyzed by western blot in terms of their reactivity with sera from patients with Chagas' disease. In addition, sera from patients with visceral (AVL) and tegumental leishmaniasis (ATL) were also tested in order to identify cross-reactivities with Trypanosoma cruzi antigens. Twenty eight polypeptides with molecular weights ranging from 14 kDa to 113 kDa were identified with sera from Chagas' disease patients. An extensive cross-reactivity was observed when sera from human visceral leishmaniasis were used, while only a slight cross-reaction was observed with sera from tegumental leishmaniasis. On the other hand, 10 polypeptides specifically reacting with sera from Chagas' disease patients were identified. Among them, the antigens with molecular weights of 46 kDa and 25 kDa reacted with all sera tested and may be good candidates for specific immunodiagnosis of Chagas' disease. 相似文献
948.
949.
Role of phospholipase A2 in the stimulation of sponge cell proliferation by homologous lectin 总被引:2,自引:0,他引:2
M Gramzow H C Schr?der U Fritsche B Kurelec A Robitzki H Zimmermann K Friese M H Kreuter W E Müller 《Cell》1989,59(5):939-948
Using the Geodia cydonium system, we showed that after incubation of competent sponge cells in the presence of lectin, phospholipase A2 was released from the cells. The substrates for this enzyme, phosphatidylethanolamine and phosphatidylcholine, were identified in the extracellular material of sponge tissue. In addition, the phospholipase A2 inhibitor calelectrin was identified by immunobiochemical techniques; this molecule was associated with the aggregation factor. Reconstitution experiments strongly suggested that phospholipase A2 catalyzed the release of arachidonic acid, which is then taken up by the cells. Intracellularly, arachidonic acid was metabolized primarily to prostaglandin E2. Inhibition studies revealed that prostaglandin E2 is involved in the ultimate increase of DNA synthesis. These findings suggest that the phospholipase A2-arachidonic acid system is involved in the matrix-initiated signal transduction pathway in sponges. 相似文献