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11.
The effect of alkaline phosphatase (3.1.3.1) on desensitization of beta-adrenoceptor-responsive adenylate cyclase and the role of phosphorylation in desensitization were examined. Treatment of rat reticulocytes with isoproterenol, dibutyryl cAMP and tetradecanoyl phorbol acetate (TPA) caused the desensitization of beta-adrenoceptor-coupled adenylate cyclase. When the membranes from dibutyryl cAMP- and TPA-desensitized cells were incubated with alkaline phosphatase for 60 min at 30 degrees C, pH 8.0, the desensitization of isoproterenol-stimulated adenylate cyclase was markedly attenuated in both preparations. When the membranes from isoproterenol-desensitized cells were treated with alkaline phosphatase under the same conditions, the attenuation of the desensitization of alkaline phosphatase was less than in the case of treatment with dibutyryl cAMP or TPA. In other words, isoproterenol-induced desensitization was more resistant to alkaline phosphatase treatment. Isoproterenol- and dibutyryl cAMP-induced desensitization of NaF-stimulated adenylate cyclase were also attenuated by alkaline phosphatase treatment. Although the stability of the Gs-catalytic unit complex of adenylate cyclase was reduced by isoproterenol treatment, the reduction of stability was also decreased by alkaline phosphatase treatment.  相似文献   
12.
It has already been reported that MR imaging is a superior imaging technique to detect minute anatomical changes in the kidney after ESWL. However, the morphological abnormalities found by MR imaging do not necessarily mean deterioration of the renal function. The purpose of this study is to assess the morphological changes in the kidney and changes in renal function after the ESWL treatment by dynamic MR imaging. A total of 16 patients underwent axial MR imaging before and after ESWL. Dynamic MR was also performed on 11 patients of them within 24 hours after ESWL, and both before and after ESWL in the remaining 5 patients. Eight kidneys showed morphological abnormalities on T1-weight images, and 4 of them showed loss of corticomedullary demarcation. Furthermore, the first MR imaging after injection of GdDTPA revealed focal areas of decreased signal intensity in only 2 of these 4 patients who showed loss of corticomedullary demarcation on previous MR images. However, the second MR imaging 6 months after ESWL showed no abnormality in either of them. The percent contrast of signal intensity increase to fat signal intensity was one minute after GdDTPA injection compared before and after ESWL in 5 of the 16 patients. The values before and after ESWL revealed no statistically significant difference, and no patient showed any remarkable decrease of signal intensity after ESWL. These results suggest that loss of corticomedullary demarcation after ESWL does not necessarily reflect damage to the renal function and that the shock-wave exposure causes no permanent damage to the renal function but only temporary impairment.  相似文献   
13.
We report a patient of relapsing polychondritis (RP) with antecedent aseptic meningitis. A 65-year-old man has developed headache and fever. Neurological examination showed meningeal signs, and cerebrospinal fluid (CSF) examination revealed meningeal inflammation which contained 450 polymorphonuclear cells/microl, 302 mononuclear cells/microl, and 0 red cells/microl, with 79 mg protein/dl. Serologic testing for autoimmune disease as well as the culture and cytology of CSF were negative. He admitted our hospital as having aseptic meningitis and experienced antibiotic therapy. However, his pyrexia continued and he developed repeating visual and hearing impairment reacting to steroid. Three months later, he became behaviorally deaf, and bilateral auricular chondritis occurred with nonerosive seronegative inflammatory polyarthritis. The result of condral biopsy was consistent with the diagnosis of RP showing cartilage surrounded by an intense inflammatory cell response with a decreased number of chondrocytes. A clinical diagnosis was made and prednisolone 60 mg/day was begun with the result of resolution of the auricular chondritis, and slight improvement of his deafness. Aseptic meningitis is a rare complication of RP. Only one report detailed RP patient who had preceding meningitis. RP is a potentially lethal disease resulting from suffocation by airway collapse, the complications of a cardiac large vessel, and so on. For improvement of a life prognosis, an early diagnosis and treatment are indispensable. Although RP is a rare discovery, it is necessary that RP should be taken into consideration and be differentiated as a cause of relapsing aseptic meningitis.  相似文献   
14.
Summary The authors describe an approach through the temporal horn of the lateral ventricle which proved to be useful for clipping of a large dorsal type basilar bifurcation aneurysms. It facilitates the preservation of the perforating arteries behind the aneurysm, because it gives sufficient working space to move the aneurysm dome. Furthermore this approach avoids many of the disadvantages of other approaches, especially the risk of iatrogenic injuries of the Sylvian or Labe's vein.  相似文献   
15.
Long-term toxicity/carcinogenicity of musk xylol in B6C3F1 mice   总被引:3,自引:0,他引:3  
The long-term toxicity/carcinogenicity of musk xylol, a synthetic nitro musk, was examined in B6C3F1 mice of both sexes. Musk xylol was administered at dietary levels of 0 (control), 0.075 or 0.15% for 80 wk. The overall tumour incidences in all treated groups of both sexes were significantly higher than those in the corresponding controls. Combined malignant and benign liver cell tumours were clearly increased in both sexes, and in males a positive significant trend was also noted for the occurrence of hepatocellular carcinomas. In males the incidence of Harderian gland tumours was also significantly greater in treated groups than in controls. Some other neoplasms, such as lung tumours in both sexes and Harderian gland tumours and lymphomas in females, occurred in greater numbers in the treated groups, although the differences were not statistically significant in comparison with the controls. In addition, the incidences and total numbers of malignant tumours were significantly increased in treated groups of both sexes, although the increases were not dose dependent. The results demonstrated that musk xylol is carcinogenic in B6C3F1 mice when given at dose levels of 0.075 or 0.15% in the diet for 80 wk.  相似文献   
16.
An animal model, using distraction force on adult rabbits, was developed to study the effects of nonweight-bearing on articular cartilage in a moving joint. Histologic evaluation was used to compare the morphology of chondrocytes, safranin O intensity, cartilage thickness, and structural changes between the test and contralateral joints. At 3 and 6 weeks, the chondrocytes in superficial and intermediate zones were round, with an increase in cellular volume density and mean cell volume and with less metachromasia; the safranin O intensity and cartilage thickness were the same as in the controls. In cartilage of the 9-week group, mean cell volume decreased with cell cloning in the superficial zone, while numerical density increased and mean matrix volume per cell decreased in the superficial and intermediate zones. The cartilage, with a 34% reduction in thickness and a 53–72% decrease in safranin O intensity from the superficial to the deep zone, had superficial fibrotic proliferation, suface erosion or depression, ard tidemark irregularity. Continuous distraction in a moving joint caused morphological changes in chondrocytes prior to degeneration of cartilage. These results support the hypothesis that the forces perceived by cells may dictate their shape and then stimulate alterations in cellular biochemistry and matrix metabolism.  相似文献   
17.
Significance of magnetic resonance imaging in acute head injury   总被引:2,自引:0,他引:2  
One hundred seventy-seven patients who had incurred head trauma were studied with magnetic resonance imaging (MRI). Patients varied from those with mild injury without any focal neurological deficit to those with severe injury with post-traumatic coma. Altogether, 177 lesions were demonstrated by MRI in 123 of 177 patients within 3 days of injury using T2-weighted (SE2000/40,2000/111) and T1-weighted (IR1500/500/40) multislice sequences. In contrast, computerized tomography (CT) demonstrated 103 lesions in 90 patients. MRI was superior to CT in the diagnosis of nonhemorrhagic contusions demonstrated as a high-intensity area on T2-weighted imaging. MRI provided some information to evaluate the severity of diffuse axonal injury or to predict delayed traumatic intracerebral hematoma (DTICH).  相似文献   
18.
CA 125 is an antigen associated with non-mucinous epithelial ovarian cancer, which is defined by OC 125 antibody developed by immunizing ovarian cancer cells. We have produced two monoclonal antibodies, 130-22 and 145-9, by using the human lung adenocarcinoma cell line PC-9. Both 130-22 and 145-9 antibodies recognized CA 125 antigen. However, the binding sites seemed to be separate from those of OC 125. Testing by 9 immunoradiometric assays (IRMA), using different combinations of the 3 monoclonal antibodies 130-22, 145-9 and OC 125 demonstrated that the best standard curve for detecting CA 125 could be obtained by a "simultaneous sandwich" assay based on a mixture of 125I-labeled OC 125 and 130-22 or 145-9 coated beads. One-step IRMA, using 130-22 as a tracer and 145-9 as an immunoadsorbent, also showed good reproducibility and sensitivity for measuring CA 125. Antigens were detectable in the culture supernatants of PC-9 cells and 5 of 6 ovarian cancer and endometrial adenocarcinoma cells. These results indicate that one-step IRMA using 130-22 and 145-9 is useful for detecting CA 125 antigen.  相似文献   
19.
The effects of 1-antitrypsin ( 1,-AT), 1,-acid glycoprotein ( 1AGP), and haptoglobin (Hp), the main constituents of-globulin and which belong to acute phase proteins, on NK activity were examined using K562 cells as the NK target cells. Among the three proteins, 1,-AT and 1AGP had inhibitory effects on NK activity for fast target K562 cells. The,-AT preparations having the same protein concentration and a different trypsin inhibitory capacity (TIC) had an equal effect. Although 1AT and 1,-AGP equally reduced the NK activity, the mechanism involved in the reduction differed, in that the effect of 1,-AT directed toward NK cells reduced their binding capacity with the target cells, 1,-AGP probably interacts with a cytotoxic factor secreted from NK cells following effector-target interaction. These studies suggest that each of the acute-phase proteins, which increase following inflammation, inhibits NK cell function by two distinct mechanisms.  相似文献   
20.
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