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21.
22.
K Kamakura S Ishiura S Imajoh N Nagata H Sugita 《Journal of neuroscience research》1992,31(3):543-548
The ubiquitous existence of calcium-activated neutral protease (CANP, calpain), an enzyme whose activity is regulated by calcium ions and a specific endogenous CANP inhibitor (calpastatin), is well known. Although there has been much investigation concerning the distribution and role of CANP, investigations of the distribution of the CANP inhibitor using immunohistochemical techniques are rare. We made antiserum against a 40K fragment of cDNA corresponding to two C-terminal repeats of rat liver CANP inhibitor expressed in Escherichia coli. Using this antiserum, we examined the distribution of CANP inhibitor in the rat central nervous system by the ABC technique and compared it with the distribution of CANP. Neurons and glias were stained, with the cytosol stained diffusely and the cell membranes stained clearly and strongly. Axons and myelin were stained faintly, but nuclei and vessels were not stained. The distribution of CANP inhibitor was thus found to be similar to that of CANP. 相似文献
23.
Chikao Yutani Masami Imakita Hatsue Ishibashi-Ueda Seiki Nagata Hiroshi Sakakibara Yasuharu Nimura 《Pathology international》1987,37(6):1041-1052
The heart of seven cases of fatal congestive heart failure with dilated left ventricle, developing in 5 patients with symptomatic hypertrophic cardiomyopathy (HCM) and 2 patients with histologically widespread disarray of both ventricles, was morphologically investigated. These 7 cases showed myocardial widespread disarray and massive fibrosis, the mean percent area of fibrosis was 40.6% and 59.4% at upper and lower levels of left ventricles, respectively. Fibrosis was most extentsive in the lateral wall, and followed by anterior, posterior and interventricular walls. The severity of cell infiltration in left ventricle was completely matched to that of fibrosis and was most extensive in subepicardial area followed by middle and subendocardial areas of left ventricle. The intima and medial thickness of intramural small arteries in the fibrotic areas was significantly larger (p<0.05) than that of nonfibrotic areas, which suggested that the effect of intramural small artery was not essential for pathogenesis of massive fibrosis. ACTA PATHOL. JPN. 37: 1041 -1052, 1987. 相似文献
24.
H. Noguchi M. Ueda Y. Nakai Y. Iwanaga T. Okitsu H. Nagata Y. Yonekawa N. Kobayashi T. Nakamura H. Wada S. Matsumoto 《American journal of transplantation》2006,6(3):496-504
Islet allotransplantation can achieve insulin independence in patients with type I diabetes. Recent reports show that the two-layer method (TLM), which employs oxygenated perfluorochemical (PFC) and UW solution, is superior to simple cold storage in UW for pancreas preservation in islet transplantation. However, UW solution has several disadvantages, including the inhibition of Liberase activity. In this study, we investigated the features of a new solution, designated M-Kyoto solution. M-Kyoto solution contains trehalose and ulinastatin as distinct components. Trehalose has a cytoprotective effect against stress, and ulinastatin inhibits trypsin. In porcine islet isolation, islet yield was significantly higher in the M-Kyoto/PFC group compared with the UW/PFC group. There was no significant difference in ATP content in the pancreas between the two groups, suggesting that different islet yields are not due to their differences as energy sources. Compared with UW solution, M-Kyoto solution significantly inhibited trypsin activity in the digestion step; moreover, M-Kyoto solution inhibited collagenase digestion less than UW solution. In conclusion, the advantages of M-Kyoto solution are trypsin inhibition and less collagenase inhibition. Based on these data, we now use M-Kyoto solution for clinical islet transplantation from nonheart-beating donor pancreata. 相似文献
25.
Monoclonal antibodies to human hemoglobin were produced and a colloidal gold agglutination method has been developed for detection of fecal occult blood. Since hemoglobin is composed of the tetramer, alpha 2 beta 2, a single monoclonal antibody-labeled colloidal gold can agglutinate with hemoglobin. The lowest detectable hemoglobin concentration was 0.5 micrograms/ml. A total of 785 fecal samples were determined using colloidal gold agglutination and compared with latex agglutination. The colloidal gold agglutination detected blood in 75 samples, whereas latex agglutination detected blood in 76 samples, and among them 70 were positive in both methods. Overall agreement between the two methods was 98%. 相似文献
26.
K Okajima Y Nagata M Mitsumori T Ishigaki I Kimura Y Nakano K Minato M Komori K Sato T Takahashi 《Radiology》1992,183(2):569-572
To investigate spatial resolution requirements for digitized portal images in radiation therapy, observer performance tests were performed. One hundred twenty portal images were digitized with sampling frequencies of 0.700, 0.350, and 0.175 mm for observation. Receiver operating characteristic analysis was used to determine the acceptable sampling frequency for clinical portal images. The detectability of setup errors was significantly better on the original images than on the digitized images with sampling frequencies of 0.700 mm (P = .005) and 0.350 (P = .046). Some clinical disadvantages might accrue with the use of a sampling frequency of 0.350 mm or larger. 相似文献
27.
M Kuriyama Y Hokezu S Togo K Nagata K Takahashi T Igakura M Osame 《Nihon Ronen Igakkai zasshi. Japanese journal of geriatrics》1992,29(7-8):559-564
Serum lipid, lipoprotein, apolipoprotein, and sterol profiles were studied in 22 patients with senile dementia of the Alzheimer type (SDAT) and 29 patients with vascular dementia (VD). Levels of high density lipoprotein-cholesterol (HDL-C) were lower in both patients groups of SDAT and VD than in control group. Apolipoprotein AI and AII are two major proteins in HDL. In this study, apolipoprotein AI levels were normal, but apolipoprotein AII levels were lower in the patient groups, especially in the VD group, than in the control group. Lipoprotein(a) levels were higher in both patient groups, especially in the VD group. There were no differences of cholesterol, cholesterol precursors (desmosterol and lathosterol), and plant sterols (campesterol and beta-sitosterol) among the three groups. Murine apolipoprotein AII is a serum precursor of murine senile amyloid protein, and the apolipoprotein AII variant with proline-->glutamine substitution at position 5 in the serum of accelerated senescence-prone mice is identical to the murine senile amyloid fibril protein from amyloid-deposited tissues of these mice. In human SDAT and VD, the reason for the low level of apolipoprotein AII remains unclear. 相似文献
28.
Kohji Nagata Michiko Horinouchi Miyuki Saitou Michiyo Higashi Mitsuharu Nomoto Masamichi Goto Suguru Yonezawa 《Journal of hepato-biliary-pancreatic sciences》2007,14(3):243-254
In this review article, we demonstrate the mucin expression profile in normal tissue, invasive ductal carcinoma (IDC), two subtypes of intraductal papillary–mucinous neoplasm (IPMN dark cell type and IPMN clear cell type), pancreatic intraepithelial neoplasia (PanIN), and mucinous cystic neoplasm (MCN) of the pancreas. In MUC1, there are various glycoforms, such as poorly glycosylated MUC1, sialylated MUC1, and fully glycosylated MUC1. IDCs showed high expression of all the glycoforms of MUC1. IPMNs dark cell type showed no expression or low expression of all the glycoforms of MUC1. IPMNs clear cell type showed low expression of poorly glycosylated MUC1, but expression of sialylated MUC1 and fully glycosylated MUC1. Expression of MUC2 was negative in IDCs, high in IPMNs dark cell type and low in IPMNs clear cell type. MUC5AC was highly expressed in IDCs, IPMNs dark cell type, and IPMNs clear cell type. MUC6 expression was higher in IPMNs clear cell type than in IDCs and IPMNs dark cell type. Our recent study demonstrated that high expression of MUC4 in IDCs is correlated with a poor outcome for patients. In PanINs, expression of both MUC5AC and MUC6 are an early event, whereas up-regulation of MUC1 is a late event. MCNs do not look as if they will show a specific mucin expression profile according to the literature review. 相似文献
29.
Surgical strategies for treatment of giant or large intracranial aneurysms: our experience with 139 cases. 总被引:3,自引:0,他引:3
Y Kato H Sano S Imizu M Yoneda M Viral J Nagata T Kanno 《Minimally invasive neurosurgery》2003,46(6):339-343
Giant or large intracranial aneurysms are the vascular neurosurgeon's greatest challenge. At our department, we have treated one hundred and thirty nine patients with giant or large intracranial aneurysms between 1975 and 2001. These included 37 partially thrombosed giant aneurysms. 75 aneurysms were giant (> 2.5 cm) and 64 were large aneurysms (2-2.5 cm). Three-dimensional computed tomography angiograms were performed in patients besides MRI angiography and digital subtraction angiography. These were found to be very valuable in the preoperative assessment of surgical anatomy of the aneurysm with respect to the branch arteries and perforators origin besides knowing the relations to the skull base. With our experience in surgical treatment of these 139 cases, we find that the basic technique is trapping and evacuation and not just clipping of the aneurysm neck but also reconstruction of the artery bearing the aneurysm, especially with wide-necked aneurysms. Use of multiple clipping, tandem clipping or dome clipping as per the intraoperative situation, is very helpful in dealing with giant aneurysms as also is the use of different types of clips like fenestrated clip with straight clip (combination clipping), booster clip, dome clips etc. While selecting surgical strategy for partially thrombosed giant aneurysm, securing the neck is most important. If the neck is too narrow to reconstruct, aneurysmectomy with anastomosis is one of the surgical strategies. An extracranial intracranial bypass should be considered in cases where clipping or parent artery ligation is expected to be associated with compromise of cerebral circulation. 相似文献
30.