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991.
992.
K Ishikawa M Shimizu M Ohno M Morishita I Ogawa T Hayashi Y Sakaguchi K Yamashita H Koka N Kamata 《Japanese circulation journal》1991,55(3):213-220
The clinical features of acute myocardial infarction patients in whom abnormal Q wave disappeared were analyzed. Of 201 patients, 40 (20%) (Group A) showed disappearance of Q wave in serial electrocardiograms. Regional ejection fraction of the infarcted portion improved significantly (from 24 +/- 2 to 34 +/- 4%, p less than 0.001) during chronic phase in Group A, but no such improvement was present in Group B patients who showed no change in the Q wave. Global ejection fraction was greater and percent akinetic segment was smaller in Group A than in Group B at chronic phase. Coronary occlusion occurred more often at segment 7 in Group A; in Group B, occlusion occurred more frequently upstream at segment 6, suggesting Group A had a smaller area of risk. Spontaneous recanalization was more often (57%) and complete occlusion was less frequent in Group A. These indicate that Group A is characterized by a smaller area of risk, smaller infarct size, earlier reperfusion, and greater improvement in wall motion. Twenty-eight patients (70%) of Group A lost Q wave within one month and 12 patients (30%), after 3 months or more. Electrical stunning of the myocardium may be a possible mechanism for the early disappearance of Q waves, and anatomical healing for the late disappearance of Q waves. 相似文献
993.
Human immunodeficiency virus infection of megakaryocytic cells 总被引:4,自引:0,他引:4
The human immunodeficiency virus (HIV) is capable of infecting certain cells of hematopoietic lineage, particularly monocyte-macrophages and T lymphocytes. Recently, the possibility that cells of megakaryocytic lineage are susceptible to HIV infection has been raised. We have characterized infection of the permanent megakaryocytic cell line CMK by HIV in vitro. CMK cells were easily infected by HIV type 2 (HIV-2), producing significant amounts of virus in culture. Infection appeared to be mediated by the CD4 surface antigen on CMK cells. Three different strains of HIV-1 were able to minimally infect CMK cells, suggesting there may be isolates of HIV tropic for megakaryocytes. Infection of CMK cells led to downregulation of the CD4 surface antigen but no discernable change in expression of megakaryocyte-associated proteins glycoprotein Ib and glycoprotein IIb/IIIa. These observations support the likelihood that megakaryocytes are susceptible to HIV infection, and cell lines of megakaryocytic origin may provide a useful model to study effects of the retrovirus on megakaryocyte function. 相似文献
994.
Self peptide requirement for class II major histocompatibility complex allorecognition 总被引:1,自引:1,他引:1 下载免费PDF全文
S Demotz A Sette K Sakaguchi R Buchner E Appella H M Grey 《Proceedings of the National Academy of Sciences of the United States of America》1991,88(19):8730-8734
Using a dinitrophenylated and biotinylated peptide antigen, we have developed an affinity chromatography procedure to purify complexes of a given peptide species and a given class II major histocompatibility complex antigen away from class II molecules occupied by other peptides. We show that hen egg lysozyme peptide-I-Ed complexes purified according to this procedure have a greatly enhanced capacity to activate hen egg lysozyme-specific T cells but have lost the capacity to activate three different alloreactive T-cell hybridomas. These data demonstrate that the class II molecule in and of itself is not sufficient to activate alloreactive T cells. Rather, the data suggest that recognition of specific complexes formed between allo-class II and particular autologous peptides may be required. Alternatively, alloreactive T cells may be recognizing "empty" major histocompatibility complex molecules. 相似文献
995.
In vitro and in vivo antibacterial activities of AT-4140, a new broad-spectrum quinolone. 总被引:7,自引:43,他引:7 下载免费PDF全文
S Nakamura A Minami K Nakata N Kurobe K Kouno Y Sakaguchi S Kashimoto H Yoshida T Kojima T Ohue et al. 《Antimicrobial agents and chemotherapy》1989,33(8):1167-1173
AT-4140, 5-amino-1-cyclopropyl-6,8-difluoro-1,4-dihydro-7-(cis-3,5- dimethyl-1-piperazinyl)-4-oxoquinoline-3-carboxylic acid, showed broad and potent antibacterial activity. Its MICs for 90% of the strains tested were 0.1 to 0.78 micrograms/ml against gram-positive organisms, such as members of the genera Staphylococcus, Streptococcus, and Enterococcus, and 0.0125 to 1.56 micrograms/ml against gram-negative organisms, such as members of the family Enterobacteriaceae and the genera Pseudomonas, Branhamella, Campylobacter, Haemophilus, and Neisseria. Its MICs were 0.025 to 0.78 micrograms/ml against glucose nonfermenters, such as members of the genera Xanthomonas, Acinetobacter, Alcaligenes, Moraxella, Flavobacterium, and Brucella; 0.2 to 0.78 micrograms/ml against anaerobes, such as Clostridium perfringens and Bacteroides fragilis; 0.0125 to 0.05 micrograms/ml against Legionella spp.; 0.0125 to 0.2 micrograms/ml against Mycoplasma spp.; 0.031 to 0.063 micrograms/ml against Chlamydia spp.; and 0.1 to 0.3 micrograms/ml against Mycobacterium spp. The potencies of AT-4140 against gram-negative organisms were comparable to those of ciprofloxacin and higher than those of ofloxacin, enoxacin, and norfloxacin. The potencies of AT-4140 against gram-positive organisms, glucose nonfermenters, anaerobes, Mycoplasma spp., Chlamydia spp., and Mycobacterium spp. were generally higher than those of the quinolones with which AT-4140 was compared. AT-4140 showed good oral efficacy against systemic infections with Staphylococcus aureus, Streptococcus pyogenes, Streptococcus pneumoniae, Escherichia coli, and Pseudomonas aeruginosa in mice. Its efficacy was better when a daily dose was given once than when it was given in two doses. Good efficacies of the orally administered drug were also observed in pulmonary, dermal, and urinary tract infection models in mice. The in vivo efficacies of AT-4140 were equal to or better than those of ciprofloxacin, ofloxacin, enoxacin, and norfloxacin. 相似文献
996.
We present a case of meningeal carcinomatosis with bilateral hearing loss secondary to a rectal adenocarcinoma. A 60-year-old woman developed progressive loss of hearing in the left ear 19 months after an abdominoperineal resection for an adenocarcinoma of the rectum. Three months after the onset of left hearing loss, she visited our hospital. Pure tone audiometry revealed profound sensorineural hearing loss in the left ear and mild sensorineural hearing loss in the right ear. Gadolinium-enhanced MRI revealed tumor in the left internal auditory canal and cerebellopontine angle and enhancement in the right internal auditory canal. Six days after the first examination, pure tone audiometry revealed profound loss of hearing in the right ear. DPOAE of the right ear were still detected 6 days after the first examination, but were clearly decreased 9 days after it, and reached noise level 10 days after it. Gadolinium-enhanced MRI revealed rapid growth of the tumor of the right internal auditory canal and cerebellopontine angle. We clearly demonstrate here the rapid course of hearing loss using pure tone audiometry, MRI, and DPOAE. 相似文献
997.
Matsuda H Sakaguchi K Shibasaki T Takahashi H Kawakami Y Furuya K Kikuchi Y 《Journal of perinatal medicine》2005,33(3):199-205
OBJECTIVE: The aim of this study is to identify suitable applications for cerebral MR (magnetic resonance) scanning in cases of severe preeclampsia and eclampsia through comparison of clinical course and easily accessible parameters. METHODS: From January 2001 to December 2003, cerebral MR scans were performed on 43 women with severe preeclampsia; of those 41 were enrolled in data analyses. Twenty clinical parameters, including age, body mass index, blood pressure, liver and renal function, and coagulation status, were compared for each patient. Data were analyzed using the SPSS program on a VAX main frame. RESULTS: Among 41 severe preeclamptic women, abnormal MR images were observed in 11 cases including six with systemic seizures. Predictive accuracy of eclampsia with abnormal cerebral MR imaging was 84.9% (P=0.00001), while only 14.3% of severe preeclampsia cases had been diagnosed radiologically. Statistical analysis suggests diastolic BP and serum AST as predictive parameters for abnormal MR images with 82.9% predictive accuracy (P=0.0007). CONCLUSIONS: Cerebral edema can be observed in preeclamptic patients developing eclampsia. Rapid delivery is indicated when diastolic BP and AST are elevated. MR scanning is useful when delivery is delayed due to fetal immaturityin cases of severe preeclampsia. 相似文献
998.
K Yamaguchi H Negoro H Hama K Kamoi T Sakaguchi 《Nippon Naibunpi Gakkai zasshi》1979,55(10):1286-1295
As the greater part of the immunoreactive angiotensin II in cerebrospinal fluid has been suggested to be angiotensin III, a comparison was made between the effects on vasopressin release of angiotensin II and angiotensin III administered into the third cerebral ventricle in conscious male rats. The blood samples were collected 90 seconds after the injection of angiotensin II or angiotensin III by means of decapitation. Plasma vasopressin (microU/ml) extracted and determined by radioimmunoassay were 2.3 +/- 0.8, 6.7 +/- 5.0, 14.0 +/- 2.2, 16.3 +/- 4.3 and 20.7 +/- 2.5 (mean +/- SEM), respectively following the injection of 0, 10, 25, 50 and 100ng of angiotensin II. The increases in plasma vasopressin produced by angiotensin II 25, 50 and 100ng were statistically significant (p less than 0.05). On the other hand, plasma vasopressin following the injection of 22.7 and 45.4ng of angiotensin III, which are equimolar to 25 and 50ng of angiotensin II each, were 14.9 +/- 2.7 and 16.3 +/- 5.6, respectively. No significant difference was found between the effect on plasma vasopressin of angiotensin II and that of angiotensin III at the dose level of 24.3 or 48.6 p. mol. These data indicate that angiotensin III is equipotent to angiotensin II in terms of vasopressin release when administered into the third cerebral ventricle. The possible role of angiotensin III in the brain on vasopressin secretion is discussed. 相似文献
999.
Anti-endothelial cell antibodies: detection and characterization in sera from patients with autoimmune hypoparathyroidism 总被引:3,自引:0,他引:3 下载免费PDF全文
A Fattorossi G D Aurbach K Sakaguchi A Cama S J Marx E A Streeten L A Fitzpatrick M L Brandi 《Proceedings of the National Academy of Sciences of the United States of America》1988,85(11):4015-4019
In a previous report, we described antibodies in autoimmune hypoparathyroidism (AHP) that are cytotoxic for cultured bovine parathyroid cells. In the present study, we show that sera from six AHP patients, but not from 26 patients with other autoimmune diseases or from 7 healthy subjects, react with bovine endothelial cells in culture (by flow cytometry and fluorescence microscopy) and in tissue sections (by immunohistology). We found uniformly that the immunoglobulin class reacting is IgM. Adsorption experiments showed that the antigenic determinants reacting with AHP sera were similar on bovine cultured endothelial cell membranes and in tissue sections of bovine parathyroid glands. The AHP sera also reacted with endothelial cells cultured from bovine adrenal medulla and pulmonary artery. Immunoblot analysis showed antibody binding to two major bands of 200 and 130 kDa solubilized from the membrane fraction of bovine parathyroid endothelial cells. Only one AHP serum consistently recognized endothelium-related structures on frozen sections of three different human parathyroid adenomas; two other sera reacted with one adenoma each; and three did not react with human adenomas. This indicates that human material is less suitable than bovine in detecting endothelium-related immune phenomena in AHP sera. The anti-endothelium IgM antibodies appear to be disease-specific but are not organ- or species-specific. The identification of endothelial cells as the target for antibodies in AHP raises the possibility that the endothelium subserves an important local function for endocrine epithelium. 相似文献
1000.
Satoshi NakamurA Shohachi Suzuki Takanori Sakaguchi Hiroyuki Konno Shozo Baba Isao Kosugi Hiroyuki Muro 《Journal of gastroenterology》1996,31(2):289-293
Curative surgery for biliary tract malignancy has improved the prognosis of patients; however, during long-term follow up
after extensive surgery, four of our patients (two with gallbladder carcinoma and two with bile duct carcinoma) developed
a second primary cancer (one each in the duodenum, skin, descending colon, and lung). Regular examination of the upper gastrointestinal
tract, colorectum, and lungs, and testing for tumor markers (carcinoembryonic antigen and CA19-9) were performed as follow-up
studies. As a result, the second cancers were all found at a relatively early stage and all four patients are still alive
6–14 years after the initial operation. A review of the annual autopsy reports over the last 5 years in Japan showed that
the incidence of second cancer was 14.8% in patients with gallbladder carcinoma and 13.5% in those with bile duct carcinoma.
Furthermore, the rate of second gastric and colorectal carcinoma was significantly higher in patients with primary bile duct
cancer than in those with primary gallbladder cancer. In conclusion, the incidence of a second cancer after resection of biliary
tract malignancy is more than 10%, but this second cancer can be detected relatively easily and treated at an early stage
during the course of regular long-term follow up for the first cancer. 相似文献