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991.
(1) Narrowness of the early-diastolic and presystolic peaks on the echo curve of the anterior mitral leaflet and an abnormal step formation at the middle or higher level on the descending limb of the presystolic peak were observed in 7 cases with congestive cardiomyopathy or myocardial fibrosis, 1 case with myocardial infarction, and 1 case with cardiomyopathy due to progressive muscular dystrophy. (2) This abnormal pattern is considered to be closely related to the myocardial condition in the above-mentioned diseases. (3) Probable mechanisms for this pattern formation are considered as follows: (i) a sudden reduction of distensibility of the left ventricle after filling of the ventricle over a certain limit near full-filling, and impaired ventricular contractility, (ii) restriction in the mobility of the mitral valve and its chardae due to thier inability to adapt themselves to a developed dilatation of the left ventricle. (4) A similar presystolic step formation on the echo curve of the anterior mitral leaflet was observed in 3 of 25 cases of hypertrophic cardiomyopathy of Goodwin's sense. Differences between the myocardial state in congestive cardiomyopathy or in similar myocardial diseases and that in hypertrophic cardiomyopathy were also discussed. 相似文献
992.
993.
S Nomura T Soga M Yanabu M Suzuki K Kondo N Sone C Kitada H Nagata T Kokawa K Yasunaga 《[Rinshō ketsueki] The Japanese journal of clinical hematology》1989,30(2):164-168
We investigated platelets and plasma from patients with idiopathic thrombocytopenic purpura (ITP) to elucidate the antigenic determinants at which their autoantibodies are directed, and studied the relationship between anti-platelet antibody and platelet volume. We used flow cytometry to detect platelet-associated IgG (PAIgG), C3 (PAC3), IgM (PAIgM) and platelet volume, and also to determine the binding rate of monoclonal anti-platelet antibodies in patients with ITP. The following results were obtained. 1. Both anti-GPIIb/IIIa autoantibodies (21 of 71 patients) and anti-GPIb autoantibodies (3 of 71 patients) were found in ITP. 2. The decrease in platelet count in patients without anti-GPIIb/IIIa autoantibodies was significant. 3. The increase in platelet volume was found more frequently in patients with a platelet count less than 50,000 and in untreated patients. 4. There was a positive correlation between the platelet volume and PAIgM in patients with a platelet count less than 30,000 and high levels of PAIgM. 相似文献
994.
995.
Shigeru Kimura Akira Watanabe Masafumi Nagata Yasuko Niinomi Minoru Harada 《Immunological investigations》1996,25(5):425-434
To determine the main mediators for mouse anaphylactic shock, the suppression of active anaphylactic shock by cyproheptadine, an antagonist of histamine/serotonin, and CV-6209, an antagonist of platelet-activating factor (PAF), was systematically evaluated using various mouse strains. The suppression was quite heterogeneic depending on the mouse strain and method for sensitization. When sensitization was done with bovine serum albumin (BSA) plus Bordetella pertussis organisms, anaphylactic shock in C57BL/6N mice was suppressed by cyproheptadine but not by CV-6209. In contrast, shock in C3H/HeN and WBB6F1-W/WV mice was suppressed by CV-6209 but not by cyproheptadine. Shock in BALB/c mice was suppressed by both agents but that in WBB6F1-+/+ mice was not at all by either one. DS and BDF1 mice showed differences due to the length of the sensitization period; shock was not suppressed by cyproheptadine with a shorter sensitization (9 to 11 days) but clearly suppressed with prolonged sensitization of 14 to 15 days. Shock in DS, WBB6F1-+/+ and BDF1 mice, which was not suppressed by either agent alone, was strongly suppressed by the combination of the two agents. In animals which had been sensitized with BSA emulsified with Freund's complete adjuvant (FCA) and given DL-propranolol as a shock potentiator, a similar pattern of drug susceptibility as that in the pertussis-vaccinated animals was obtained in general, although a discrepancy was seen with regard to the suppression of CV-6209 in C3H/HeN and BDF1 mice. Synergistic suppression by CV-6209 and cyproheptadine was also very clear with the WBB6F1-+/+ mice sensitized using FCA. In addition, results quite similar to those with cyproheptadine were obtained with the other two antihistamines, triprolidine almost devoid of antiserotonin activity and oxatomide, in testing with BDF1 mice sensitized using Bordetella pertussis organisms. From these findings, the conclusion is that histamine and PAF play major roles solely or in combination in mouse active anaphylactic shock. 相似文献
996.
N Nagata Y Yasutomo N Kugai Y Matsuura T Akatsu K Sugiyama T Kinoshita O Takatani Y Mamiya K Yamaguchi 《Japanese journal of clinical oncology》1989,19(4):353-359
The pathogeneses of hypercalcemia and hypophosphatemia which developed in a patient with metastatic invasive ductal breast carcinoma were studied. The patient had low plasma levels of immunoreactive parathyroid hormone (PTH) and 1,25(OH)2D, increased nephrogenous cyclic adenosine monophosphate (cAMP) excretion and low TmPO4/GFR, suggesting the presence of humoral PTH-like activity. The tumor extract showed activities which would stimulate bone resorption in vitro and cAMP generation in the osteogenic cell line, MC3T3 E1, and in the rat kidney cortex. In addition, the extract stimulated epidermal growth factor (EGF)-independent colony formation of the NRK 49F cells in soft agar, and inhibited the binding of EGF to A431 cells, indicating it to have transforming growth factor (TGF)-alpha activity. The extract contained appreciable amounts of immunoreactive PTH-related protein (PTH-rP) but negligible amounts of immunoreactive PTH. Thus, the PTH-like activity for stimulating cAMP generation in the bone and kidney was attributed to PTH-rP. Chromatographic analyses on reverse phase high performance liquid chromatography (HPLC) separated the PTH-rP activity from that of TGF-alpha and the bone resorbing activity in vitro was found only in the fractions of PTH-rP. It was concluded that this breast cancer produced PTH-rP as well as TGF-alpha, and the former was thought to have a major role to play in the humoral hypercalcemia of malignancy observed in this patient. 相似文献
997.
H Nagata K Takahashi Y Yamane K Yoshino T Shibukawa M Kitao 《Gynecologic and obstetric investigation》1989,28(3):165-168
Tumor markers have proved to be generally useful for diagnosing and monitoring malignancy. In contrast, high levels of tumor markers disturb us for differing benign disease from malignancy. We had 5 cases with benign disease who showed high values of tumor markers (CA 125 and CA 19-9). In this report, we illustrated 3 patients with endometriosis who showed high values of CA 125 and 2 patients with dermoid cyst who showed high values of CA 19-9. It was impossible to rule out malignant disease in all cases preoperatively. In diagnosing ovarian tumors, bimanual examination, ultrasound, CT scan and tumor markers should all be considered. 相似文献
998.
K Takeshima N Sunagawa S Nagata K Hirano Y Takagishi 《Yakugaku zasshi : Journal of the Pharmaceutical Society of Japan》1992,112(3):203-210
The morphological properties of poly(beta-hydroxybutyric acid) (PHB) or poly(L-lactic acid) microspheres loading flomoxef sodium (FMOX) were investigated with regard to FMOX release. The release profiles of FMOX from the microspheres could be divided into two types, a sustained release type and a burst one. Two representative PHB microspheres, the release profiles of which were quite different from those of FMOX, were compared in detail from a morphological point of view. The shapes of their surfaces and sections were observed by using scanning electron microscopy (SEM), and FMOX distribution was analyzed by using electron probe microanalysis. The crystallinity of polymers was further measured by powder X-ray diffratometry. There was little difference in the FMOX distribution and their microscopic properties such as sphere size, specific surface area, shape of surface and section. In contrast, water penetration into the inside of the microspheres was found to be clearly different by use of cryogenic SEM. A significant difference was also observed in the crystallinity of polymers forming the microspheres. The release of FMOX from the microspheres was affected by the crystallinity of polymers forming the microspheres, and burst phenomena occurred in case the polymer was highly crystallized. It was speculated that the crystallization of polymer induced micro voids in the microspheres which functioned as channels for water penetration. 相似文献
999.
1000.
Target cell specificity of two species of human interferon-alpha produced in Escherichia coli and of hybrid molecules derived from them. 总被引:26,自引:9,他引:17
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M Streuli A Hall W Boll W E Stewart nd S Nagata C Weissmann 《Proceedings of the National Academy of Sciences of the United States of America》1981,78(5):2848-2852
Plasmids containing cDNAs for human interferon (IfN) alpha-1, IFN alpha-2, and several hybrids of the two cDNAs, all joined identically to an Escherichia coli lac promoter fragment gave rise, in E. coli, to fused interferons (fIFNs) that had very different target-cell specificities. fIFN alpha-1 had a lower specific activity on human WISH cells than on bovine MDBK cells, while fIFN alpha-2 showed the opposite behavior. fIFN hybrids with the NH2-proximal half of fIFN alpha-2 behaved qualitatively like fIFN alpha-1, and those with the NH2-proximal half of fIFN alpha-2, behaved like fIFN alpha-2. On mouse L929 cells, fIFN alpha-2 was almost inactive, while fIFN alpha-1 showed relatively high activity. In this case, the fIFN hybrids with the COOH-proximal half of IFN alpha-1 showed activity on mouse cells, while the reciprocal hybrid did not. In many cases, the activity spectrum of the hybrids was very different from that of either parent. We propose that the IFN molecule has either two binding sites or two regions constituting the binding site, one in the COOH- and the other in the NH2-proximal half. The experimental findings can be accounted for if the fits of the two sites to their receptor counterparts on different cell lines are independent of one another. 相似文献