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21.
We examined the changes in myosin heavy-chain (HC) isoforms and fibre-type composition in rat soleus muscle using both myosin adenosine triphosphatase staining and sodium dodecyl sulphate/polyacrylamide gel electrophoresis (SDS-PAGE) analyses during the recovery period after 4 weeks of hindlimb suspension. Although there was no change in type IIc fibres after the suspension, an increase in this type of fibres was observed during the 1- to 4-week recovery period. The increase in type Ilc fibres was considered to be due to a shift from type Ila to IIc fibres. The SDS-PAGE analysis revealed the presence of the HC IId isoform, which was not observed in the control muscle, after a 4-week hindlimb suspension. The HC IId isoform gradually decreased over 3 weeks of recovery and disappeared in the 4th week of recovery after the suspension. These results suggest that the hypogravity conditions induced by hindlimb suspension stimulated the synthesis of the HC IId isoform, whereas an increase in mechanical load to the muscle accelerated the degradation of the HC IId isoform and the synthesis of type Ilc fibres during the recovery period after hindlimb suspension.  相似文献   
22.
This study was performed to investigate the mechanism involved in a decrease in the serum glucose of golden hamsters infected with plerocercoids of Spirometra erinacei. The concentration of glucagon, the activity of glucose-6-phosphatase in the liver, and the in vivo incorporation of 2-deoxyd-[1,2-3H]glucose into various organs increased in plerocercoid-infected hamsters compared with controls. Furthermore, the serum from the plerocercoid-infected hamsters enhanced the in vitro incorporation of [U-14C]glucose into adipose tissues, compared with control serum. The serum levels of immunoreactive insulin and somatomedin associated with nonsuppressible insulin-like activity in experimental animals, however, were not significantly different from those in controls. Therefore, we conclude that the decrease in serum glucose associated with plerocercoid infection is not the result of a decrease in gluconeogenesis, but the result of an increased utilization of glucose in the peripheral tissues.  相似文献   
23.
To investigate the action of the growth factor secreted bySpirometra erinacei plerocercoids, various organ weights, body weight and head-body length were measured in Snell normal and dwarf mice after injection with the serum from mice and rats. Serum from mice infected with the plerocercoids caused significant increases in the weights of the liver and spleen, in the same manner as mice infected with the plerocercoids. However, serum from rats infected with plerocercoids did not cause significant changes in these parameters. The growth factor in the serum of mice infected with plerocercoids was stable at –20°C for at least 6 months and easily passed through the peritoneum.  相似文献   
24.
Human basophils were purified from normal peripheral blood, using density gradient followed by negative panning selection. We tested the effects of hemopoietic growth factors on the survival of these basophils in vitro. In the absence of exogenous factors, basophils (purity greater than 90%) decreased in number rapidly. At day 7 only 11% of the cells remained alive in cultures; less than 1% of cells survived at day 14. Interleukin (IL)-3 maintained numbers of viable cells; cell viability was 67% at day 7 and 45% at day 14. Granulocyte-macrophage (GM)-colony-stimulating factor (CSF) exhibited slight effect on the survival; 33% of cells remained at day 7. Other growth factors including granulocyte (G)-CSF, macrophage (M)-CSF, and IL-4 had no significant effect on the survival of basophils at all. Morphological and functional characterization of cells maintained by IL-3 revealed that they belonged to the basophil lineage. These observations indicate that normal basophils possess functional receptors for IL-3 and GM-CSF and that both factors modulate immediate- and delayed-type hypersensitivity reactions by prolonging the life span of basophils.  相似文献   
25.
Fundamental morphological changes in human olivary hypertrophy.   总被引:1,自引:0,他引:1  
Morphological features of neurons in human inferior olivary nuclei were studied in 6 autopsied patients with dentato-olivary pathway lesions, who had survived for between 6 days and 15 months. Central chromatolysis-like neuronal enlargements were already present in the acute cases. Electron microscopy revealed round, homogeneous and electron-dense granules, varying in diameter from 0.15 micron to 2.5 microns, occurring frequently within the rough endoplasmic reticulum (ER) in the chromatolytic neurons of all 6 patients. No similar granules were observed in 6 controls. The vacuoles were due to dilatation of the rough ER, and often contained floccular materials. Neurofilamentous hyperplasia in the neurons was more frequently seen in the chronic cases. These findings suggest that the fundamental changes in the neurons in olivary hypertrophy occur within the rough ER.  相似文献   
26.
alpha 1-Antichymotrypsin (ACT) has been reported to be present in senile plaques, and ACT level is elevated in the sera of patients with Alzheimer's disease. We found that ACT has a neurotrophic activity in vitro, i.e., it enhanced neuronal survival under the culture conditions used. Hippocampal neurons were cultured in chemically defined medium containing ACT at various concentrations. In order to evaluate the number of surviving neurons semiquantitatively, enzyme immunoassay for microtubule-associated protein2 (MAP2) was carried out using anti-MAP2 antibody. Cells cultured in medium containing 4 micrograms/ml of ACT showed 1.8-fold more neurotrophic activity than those cultured without ACT.  相似文献   
27.
A case of acquired immunodeficiency syndrome (AIDS) with preceding aplastic anemia is reported. The patient was a 36 year old female who had been diagnosed as having aplastic anemia 10 years before and thereafter had received multiple transfusions. Human immunodeficiency virus (HIV)-seropositivity was revealed 10 months prior to her death, but no particular clinical signs indicating HIV infection, pre-AIDS or onset of AIDS were recognized before serological diagnosis, although the slow progression of leukopenia was noted along with thrombocytopenia. Her general condition deteriorated during the last 10 months accompanied by an acute decrease In the CD4/CD8 ratio. Autopsy revealed full-blown AIDS: systemic aspergillosis, progressive multifocal leukoencephalopathy, Epstein-Barr virus-related B cell lymphoma arising in the diaphragm and severe lymphocyte depletion in the lymph nodes and spleen. Markedly hypo-plastic bone marrow was considered to be primarily attributable to the aplastic anemia but the affection of AIDS was not excluded. The possible transmission route of HIV and the effect of the preceding aplastic anemia on the infection and clinical course of AIDS are discussed.  相似文献   
28.
The conformational energies of poly(α-methylene-γ-butyrolactone) are calculated and compared with those of poly(methyl methacrylate). In spite of the structural resemblance of these two polymers, the patterns of the energy contour maps are clearly distinguishable from each other; the energy barriers between rotational isomeric states are appreciably higher in the former than in the latter polymer. The calculation indicates large non-bonded interactions between the protons in one lactone ring and those in the adjacent lactone rings. The broad NMR spectrum of poly(α-methylene-γ-butyrolactone) apparently reflects its rigid conformational structure. 1H and 13C NMR chemical shifts are calculated by theoretical shielding calculations based on conformational analysis. Much lower magnetic field resonances of the O? CH2 and α-CH2 carbons in poly(α-methylene-γ-butyrolactone) as compared with those of the O? CH3 and α-CH3 carbons in poly(methyl methacrylate) are well reproduced by the calculation. The shift to lower magnetic field is mainly attributed to paramagnetic shielding derived from the interaction between O? CH2 carbon and α-CH2 carbon. Tacticity- and conformation-dependent 1H and 13C NMR chemical shifts of poly(α-methylene-γ-butyrolactone) are well interpreted on the basis of the conformational analysis.  相似文献   
29.
30.
Although the prostate gland is a rich source of α1-adreno- (α1-AR) and m1-cholino receptors (m1-AChR), the membrane processes associated with their activation in glandular epithelial cells is poorly understood. We used the whole-cell patch-clamp technique to show that the agonists of the respective receptors, phenylephrine (PHE) and carbachol (CCh), activate cationic membrane currents in lymph node carcinoma of the prostate (LNCaP) human prostate cancer epithelial cells, which are not dependent on the filling status of intracellular IP3-sensitive Ca2+ stores, but directly gated by diacylglycerol (DAG), as evidenced by the ability of its membrane permeable analogue, OAG, to mimic the effects of the agonists. The underlying cationic channels are characterized by the weak field-strength Eisenman IV permeability sequence for monovalent cations ( P K(25) > P Cs(4.6) > P Li(1.4) > P Na(1.0)), and the following permeability sequence for divalent cations: P Ca(1.0) > P Mg(0.74) > P Ba(0.6) > P Sr(0.36) > P Mn(0.3). They are 4.3 times more permeable to Ca2+ than Na+ and more sensitive to the inhibitor 2-APB than SK&F 96365. RT-PCR analysis shows that DAG-gated members of the transient receptor potential (TRP) channel family, including TRPC1 and TRPC3, are present in LNCaP cells. We conclude that, in prostate cancer epithelial cells, α1-ARs and m1-AChRs are functionally coupled to Ca2+-permeable DAG-gated cationic channels, for which TRPC1 and TRPC3 are the most likely candidates.  相似文献   
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