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11.
T Akiyama M Ikegami M Imanishi T Ishii T Nishioka T Uemura S Kunikata S Mitsubayashi H Kanda T Matsuura 《Nihon Hinyōkika Gakkai zasshi. The japanese journal of urology》1990,81(11):1680-1685
Both D-dimer and E fragments in urinary FDP were determined in renal transplantation patients. Urinary D-dimer fragments increased in 14 out of 20 acute rejections (70.0%) and in 6 out of 18 chronic rejections (33.3%). Urinary E fragments increased in 8 out of 9 acute rejections (88.9%) and in 4 out of 5 chronic rejections (80.0%). It is suggested that urinary FDP-E fragment is a better indicator to detect or predict rejection than the whole Urinary FDP. The appearance of D-dimer in the urine indicates intravascular coagulation in glomeruli followed by a secondary fibrinolysis in the course of the rejection reaction. The urinary D-dimer/FDP ratio which was used as the indicator of fibrinolytic activity in glomeruli was obtained in various conditions of renal transplants. The ratios were relatively high in the urines from well functioning grafts. This ratio deteriorated at the onset of rejection crisis and tended to go upward during the course of the recovery when the rejection was reversible. In the cases of irreversible acute rejection and chronic rejection, these ratios remained at a low level. D-dimer/FDP ratio might be useful indicator to predict the reversibility of rejection and the prognosis of renal allograft. Furthermore, these findings suggest that fibrinolytic and thrombolytic therapy by the tissue-type plasminogen activator (t-PA) along with immunosuppressive drugs might be more effective for the treatment of these rejections. 相似文献
12.
H. Ono R. Akiyama Y. Sakamoto J. T. Pearson H. Tazawa 《Medical & biological engineering & computing》1997,35(4):431-435
As an avian embryo grows within a eggshell, the whole egg is moved by embryonic activity and also by the embryonic heartbeat.
A technical interest in detecting minute biological movements has prompted the development of techniques and systems to measure
the cardiogenic ballistic movement of the egg or ballistocardiogram. (BCG). In this context, there is interest in using an
electromagnetic induction coil (solenoid) as another simple sensor to measure the BCG and examining its possibility for BCG
measurement. A small permanent magnet is attached tightly to the surface of an incubated egg, and then the egg with the magnet
is placed in a solenoid. Preliminary model analysis is made to design a setup of the egg, magnet and solenoid coupling system.
Then, simultaneous measurement with a laser displacement measuring system, developed previously, is made for chicken eggs,
indicating that the solenoid detects the minute cardiogenic ballistic movements and that the BCG determined is a measure of
the velocity of egg movements. 相似文献
13.
Endogenous tumor necrosis factor functions as a resistant factor against hyperthermic cytotoxicity. 总被引:4,自引:0,他引:4
Y Tsuji N Watanabe T Okamoto N Tsuji H Sasaki S Akiyama N Yamauchi Y Niitsu 《Cancer research》1992,52(22):6258-6262
One of the mechanisms of cytotoxicity by tumor necrosis factor (TNF) is the induction of reactive oxygen molecules. Cells producing endogenous tumor necrosis factor (enTNF) show resistance to the cytotoxicity of exogenous TNF by scavenging the reactive oxygen molecules. The intracellular hydroxyl radical production is also known to be involved in the heat-induced cytotoxicity. In the present study, we therefore examined the possibility that enTNF may act as a protective protein against the heat-induced cytotoxicity in a manner similar to that of exogenous TNF. Heat-sensitive L-M (mouse tumorigenic fibroblast) cells, originally expressing no enTNF, were transfected with a human TNF expression vector to produce enTNF. The stable transfectants showed apparent resistance to heat treatment. Conversely, when HeLa (human uterine cervical cancer) cells, originally producing an appreciable amount of enTNF, were transfected with an antisense TNF mRNA expression vector to inhibit enTNF synthesis, their heat sensitivity was enhanced. Furthermore, L-M cells which were transfected with nonsecretory human TNF expression vector also acquired resistance to heat treatment. In these cells, heat resistance correlated well with expression of enTNF and intracellular levels of manganous superoxide dismutase. These results indicate that enTNF exerts its intracellular protective effect against the heat-induced cytotoxicity by scavenging reactive oxygen with induced manganous superoxide dismutase in a manner similar to that found in cells treated with exogenous TNF. 相似文献
14.
Y C Park H Kiwamoto T Nishioka H Tsujihashi S Mitsubayashi T Matsuura T Akiyama T Kurita T Miyamoto 《Hinyokika kiyo. Acta urologica Japonica》1987,33(6):883-888
Combined measurement of serum prostate-specific antigen (PA) and prostatic acid phosphatase (PAP) was performed in 235 patients with various urologic diseases including 55 patients with prostatic cancer. A PA level of over 24.7 ng/ml and a PAP level of over 3.1 ng/ml were considered to be positive. The positive rate of PA was 57% in the patients with untreated prostatic cancer and 3% in the patients without prostatic cancer. The positive rate of PAP was 52% in the patients with untreated prostatic cancer and 1% in the patients without prostatic cancer. PA and PAP were considered to be equally sensitive and specific serum markers of prostatic cancer. However, the positive rate increased to 65% without increasing the false positive rate when the PA and PAP were both measured simultaneously. The combined assay of PA and PAP is recommended for screening prostatic cancer. The cross-over titer of PA and gamma-Sm using standard samples in each kit revealed linearity, which suggested that PA and gamma-Sm possess the same antigenicity. 相似文献
15.
The vitronectin receptor (VNR) is an integrin which consists of an alpha-subunit which can associate with multiple beta-subunits. A polyclonal antibody to this integrin weakly stained resting microglia in white matter of control brain and strongly stained reactive microglia in both gray and white matter of Alzheimer brain. This antibody, as well as a monoclonal antibody to beta 3, stained some platelets in capillaries of both control and Alzheimer tissue. When the antiserum was immunoabsorbed with a preparation enriched in the alpha-chain of the vitronectin receptor, it failed to stain microglial cells, but continued to stain platelets. When it was immunoabsorbed with a peripheral blood platelet preparation, all immunostaining was abolished. These results indicate that the vitronectin receptor of microglia is associated with a beta-chain different from beta 3, but that beta 3 is expressed by some platelets in brain capillaries. An antibody to vitronectin itself stained senile plaques and neurofibrillary tangles in Alzheimer entorhinal cortex, but only residual plasma in control tissue. Senile plaques positive for vitronectin had microglial cores strongly positive for the vitronectin receptor. The high levels of vitronectin receptor on reactive microglia in areas containing extracellular vitronectin suggest the possibility that vitronectin is serving an opsonizing function for microglial phagocytosis. 相似文献
16.
Takehisa Akiyama M.D. Nobutaka Osawa M.D. Kaoru Shimanuki M.D. Kimio Yashiro M.D Tadashi Oyake Ph.D. 《Pediatrics international》1991,33(1):20-26
As a model system for mucocutaneous lymph node syndrome (MCLS), we have advocated and used mice which had been rendered tolerant to Streptococcus pyogenes-associated antigens by neonatal infection with group A fteta-hemolytic streptococci, because these mice have shown a variety of peculiar bioimmunological characteristics bearing a striking resemblance to those of MCLS patients. The results of our current investigations reaffirmed the reliability of the animal model by indicating that mice subjected to neonatal infection with 5. pyogenes , or inoculation with streptococcal pyrogenic exotoxin (SPE) in Freund's adjuvant, were perfect counterparts of patients with MCLS on account of their platelet activation and hyperaggregability in response to provocative treatment, which are familiar findings in this disease. 相似文献
17.
M Yamamoto H Ukita Y Akiyama M Nishimura F Kishi Y Kawakami 《Nihon Kyōbu Shikkan Gakkai zasshi》1991,29(10):1339-1343
A 76-year-old man, whose carotid bodies had been resected for treatment of bronchial asthma 40 years previously was admitted for evaluation of abnormal arterial blood gases and exertional dyspnea. The case was diagnosed clinically as chronic pulmonary emphysema. His peripheral chemoreceptor function, estimated by hypoxic ventilatory and P0.1 response tests and withdrawal test was non-functioning. His PaCO2 value tended to rise over 50 Torr either after light exercise or during airway infection, though it was normal at rest. In addition his dyspnea had continued for 40 years in spite of carotid body resection. It was concluded that the effect of carotid body resection lasts more than 40 years and it does not have a good effect on COPD. 相似文献
18.
OBJECTIVE: The authors documented the localization and frequency of lymphatic spread in squamous cell carcinoma of the thoracic esophagus and evaluated the influence of radical systematic lymph node dissection on patient survival. SUMMARY BACKGROUND DATA: From accumulated surgical experience, it was suggested that some of the patients with lymph nodal involvement from cancer could be cured by its clearance. However, it is only recently that cancer of the esophagus has been evaluated in terms of analyzing lymphatic spread and results of lymphadenectomy. METHODS: Among 1298 patients admitted to the Toranomon Hospital between 1973 and 1993, 913 (70.3%) had resections, including curative and palliative procedures. For this study, 717 patients with TNM RO (resection with no residual tumor at operation in TNM classification) were analyzed. Survival was compared between groups of patients with less extensive thoracoabdominal (two-field) dissections and extensive collothoracoabdominal (three-field) dissections. RESULTS: Comparative study revealed that 5-year survival rate for TNM RO patients after free-field dissection (55.0%) was significantly better (log rank test, p = 0.0013) than the rate after two-field dissection (38.3%). The results were particularly significant in subgroups with stage III and IV (because of nodal factor). Overall 5-year survival rate after all resections was 42.4%. CONCLUSIONS: The role of radical lymph node dissection in cancer of the thoracic esophagus evaluated. Long-term survival was compared between two groups with two- and three-field dissection. It was concluded that survival rate was significantly better in patients with extensive three-field dissection. 相似文献
19.
Hamatani K; Yoshida K; Kondo H; Toki H; Okabe K; Motoi M; Ikeda S; Mori S; Shimaoka K; Akiyama M 《Blood》1989,74(1):423-429
Expression of six proto-oncogenes (fos, myc, myb, Ki-ras, Ha-ras, and N- ras) in 43 cases of non-Hodgkin's lymphoma was analyzed by means of in situ hybridization. Biotinylated DNA probes of the six oncogenes and those of immunoglobulin H (IgH) gene and T-cell receptor beta (TCR beta) chain gene were used. The results of in situ hybridization performed under blind conditions by IgH gene and TCR beta chain gene probes were compatible with those of typing by cell surface markers. The nuclear protein-related proto-oncogenes, fos, myc, and myb, were expressed in about 70% to 80% of all cases regardless of phenotype, histology, or histologic grade. On the contrary, genes of ras family were expressed in more limited numbers of cases except for the Ki-ras gene, which was more frequently expressed by cases of the T-cell immunophenotype with a high malignancy grade. The results of dot hybridization with RNA extracted from some cases were compatible with those of in situ hybridization, further demonstrating the specificity of in situ hybridization. 相似文献
20.
Functional changes in sigma receptors were examined after behavioral sensitization induced by repeated methamphetamine treatment. Rats received either saline or 4 mg/kg methamphetamine for 14 days. (+)3-(3-hydroxyphenyl)-N-(1-propyl)piperidine ((+)-3-PPP), a sigma receptor agonist, was given as challenge after various periods of abstinence. (+)-3-PPP at doses greater than 6 mg/kg stimulated several forms of behavior in naive rats. (+)-3-PPP at 12 and 24 mg/kg produced more frequent rearing and more intense stereotyped sniffing and repetitive head movements in rats previously sensitized with methamphetamine than in saline-pretreated rats. The augmented response to (+)-3-PPP in methamphetamine-treated rats was maintained for at least one month. The augmented response to (+)-3-PPP was reversed by the combined administration of 100 mg/kg (+/-)-sulpiride, a D2 dopamine receptor antagonist, and 30 mg/kg BMY 14802, a sigma receptor antagonist. These results suggest that repeated methamphetamine treatment induces persistent supersensitivity in sigma receptors and that it may subsequently activate the dopamine system. 相似文献