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71.
Akiomi Ogawa Masahiro Takano Kouichi Takagi Osamu Tokunaga Kohji Miyazaki 《Surgery today》1997,27(12):1167-1169
We describe herein a rare case of primary malignant melanoma of the rectum in an 85-year-old woman. The patient presented
with intermittent rectal bleeding, and a colonoscopy revealed an ulcerated polypoid mass in the rectum, located 5 cm from
the anal verge. The lesion was histologically characterized by solid growths of small round cells with scanty cytoplasm and
prominent nucleoli. Although no melanin pigment was found in the tumor cells, they were immunohistochemically positive for
HMB-45, a monoclonal antibody highly specific for malignant melanoma. Thus, HMB-45 proved very useful to establish a diagnosis
of amelanotic malignant melanoma of the rectum. 相似文献
72.
OBJECTIVE: We investigate the synaptic factor for the recovery function of evoked responses using a repetitive stimulation technique. METHODS: Somatosensory evoked cortical magnetic field (SEF) was recorded following stimulation of the median nerve using single to 6-train stimulation in 8 healthy subjects. The SEF responses after each stimulus in the train stimulation were extracted by subtraction of the waveforms. RESULTS: An attenuation of the SEF components was recognized after the second of the stimuli, but there was no significant attenuation with the third or later stimulations. The root mean square (RMS) of the 1M (peak latency at 20 ms after stimulation) and 4M (70 ms) components were smaller than that of the single stimulation during the train stimulation, while the 2M (30 ms) and 3M (45 ms) components were not attenuated, but the 3M was facilitated at the fourth to sixth stimulation. CONCLUSION: The synaptic factor was not responsible for the attenuation of the SEF components during repetitive stimulation in healthy subjects. The SEF change disclosed a functional difference among the SEF components during the train stimulation, especially among the later components. 相似文献
73.
Y Kawabata K Iwai H Sugita A Koyama S Katagiri K Takagi Y Kondo H Taniguchi K Kusajima H Ohishi 《Nihon Kyōbu Shikkan Gakkai zasshi》1992,30(2):293-301
We studied the clinico-pathological correlation of collagen disease-related pulmonary lesions to examine the pathological and radiological features of collagen lung, and the effect of steroid therapy. Ten open lung biopsy cases were examined; 4 male, and 6 female. The mean age was 55 years old. Seven cases developed pulmonary shadows after the diagnosis of collagen disease, and 3 cases showed pulmonary shadow prior to diagnosis. Pathologically, 6 cases proved to be bronchiolitis obliterans organizing pneumonia (BOOP), 3 cases were chronic interstitial pneumonia (UIP), and 1 case was acute interstitial pneumonia. All cases had inflammatory thickening of the interstitium involving the pleura, bronchial wall, and perivascular connective tissue. Half of the cases had bronchiolar inflammatory lesions. Radiologically BOOP cases showed either localized ground glass shadows, or diffuse reticulonodular shadows predominantly in the lower lung fields with shrinkage of affected areas. UIP cases showed reticulonodular shadows, and active UIP cases showed overlapping ground glass shadows. Steroids were administered in cases of BOOP and active UIP, and all cases showed improvement. We consider that open lung biopsy is of use in the diagnosis of some cases and in assessing whether steroid therapy is indicated. 相似文献
74.
Minoru Hasegawa Maki Goto Itsuki Oshima Shizufumi Ebihara 《Neuroscience and biobehavioral reviews》1995,18(4):537-540
Circadian rhythms of pineal melatonin release were measured in free-moving pigeons, Japanese quails, and chickens under light-dark cycles followed by constant dim light. Although melatonin levels differed among individual birds, circadian rhythms of melatonin were observed in all of them. Using this technique, we could examine phase shifts of melatonin rhythms and suppression of melatonin release by photic stimulation in pigeons. We could also examine effects of norepinephrine infusion on melatonin release. These results indicate that microdialysis is useful for the study of pineal melatonin rhythms in birds. 相似文献
75.
Development of inactivated vaccine against virus causing haemorrhagic fever with renal syndrome 总被引:2,自引:0,他引:2
K Yamanishi O Tanishita M Tamura H Asada K Kondo M Takagi I Yoshida T Konobe K Fukai 《Vaccine》1988,6(3):278-282
B-1 virus belonging to the hantavirus group was serially passaged in the brains of newborn mice. Inactivated vaccine was prepared from the brains after inactivation with formalin and then purification by ultracentrifugation. The antigenic potency of this vaccine in vitro was determined by antibody-bound enzyme-linked immunosorbent assay (ELISA) and serial diluted vaccine bound to an aluminium hydroxide gel was inoculated into Balb/c mice to test immunogenicity. After two injections of this vaccine preparation, antibodies were detected in the mice by immunofluorescent, neutralizing and haemagglutination inhibition antibody tests. When mice immunized with this vaccine were challenged with B-1 virus and Hantaan virus (KHF-83-61BL strain), the virus titres in their lungs and spleens were significantly less than those in non-immunized mice. These results suggest that inactivated B-1 virus vaccine is effective against virus challenge by homotypic (B-1 virus) and heterotypic (Hantaan virus) viruses. 相似文献
76.
Summary: A study was conducted to determine whether calcium blockers (CCB) have renoprotective effects, and if so to elucidate the mechanisms of such effects.
A total of 30 uninephrectomized (UNX) spontaneously hypertensive rats (SHR), 5 weeks of age, were divided into three groups. Group 1 was fed a diet containing 0.01% manidipine and 8% NaCl, while groups 2 and 3 were fed diets containing only 8 and 0.5% NaCl, respectively. Feeding of these diets began 7 days after UNX (experimental day 0). Bodyweight, urinary protein /24 h, urinary sodium excretion/24 h, and food intake were measured at certain time intervals.
At time of death (day 9 or 21), estimations of inulin clearance (Cin) and morphological evaluations, determination of glomerular sclerosis index (GSI), tubulointerstitial index (TII) and glomerular volume were performed.
Urinary protein was significantly higher in groups 1 and 2 than in group 3 from day 7 onward, but did not differ between the former two groups. Cin in group 2 was higher than in groups 1 and 3 on day 9, but declined to lower levels than in groups 1 and 3 by day 21. There was no difference in Cin between group 1 and group 3 on day 21. Morphometry (GSI and TII) revealed that renal lesions were more progressive in group 2 than in group 1. Glomeruli in group 2 were markedly larger than those in group 1, but no difference in glomerular volume was noted between groups 1 and 3.
Our findings suggest that CCB prevent progression of renal injury induced by accelerated hypertension in UNX SHR. the mechanisms of prevention may, at least in part, be related to suppression of glomerular hypertrophy. Inhibition of renal injury can be achieved without significant reduction of proteinuria. 相似文献
A total of 30 uninephrectomized (UNX) spontaneously hypertensive rats (SHR), 5 weeks of age, were divided into three groups. Group 1 was fed a diet containing 0.01% manidipine and 8% NaCl, while groups 2 and 3 were fed diets containing only 8 and 0.5% NaCl, respectively. Feeding of these diets began 7 days after UNX (experimental day 0). Bodyweight, urinary protein /24 h, urinary sodium excretion/24 h, and food intake were measured at certain time intervals.
At time of death (day 9 or 21), estimations of inulin clearance (Cin) and morphological evaluations, determination of glomerular sclerosis index (GSI), tubulointerstitial index (TII) and glomerular volume were performed.
Urinary protein was significantly higher in groups 1 and 2 than in group 3 from day 7 onward, but did not differ between the former two groups. Cin in group 2 was higher than in groups 1 and 3 on day 9, but declined to lower levels than in groups 1 and 3 by day 21. There was no difference in Cin between group 1 and group 3 on day 21. Morphometry (GSI and TII) revealed that renal lesions were more progressive in group 2 than in group 1. Glomeruli in group 2 were markedly larger than those in group 1, but no difference in glomerular volume was noted between groups 1 and 3.
Our findings suggest that CCB prevent progression of renal injury induced by accelerated hypertension in UNX SHR. the mechanisms of prevention may, at least in part, be related to suppression of glomerular hypertrophy. Inhibition of renal injury can be achieved without significant reduction of proteinuria. 相似文献
77.
During the anhepatic phase of orthotopic liver transplantation, the veno-venous bypass has been used to keep systemic hemodynamics (SHD) in a stable condition. In this study, changes of SHD and oxygen transport and consumption (OTC) during the anhepatic phase used the passive bypass (PB) with Anthron bypass tubes were compared with those used the pump-driven bypass (PDB) with a centrifugal pump in mongrel dogs. Moreover the effects of the increased instillation rate and administration of dobutamine on SHD and OTC were evaluated. The portal venous and inferior vena caval pressure were increased in PB group, but not in PDB group. Whenever PB or PDB was used, cardiac index and oxygen consumption were markedly decreased caused by hypovolemia. In PDB group trebled the instillation rate, SHD and oxygen consumption were not improved. These results suggested that the primarily cardiovascular depression during the anhepatic phase was related to the disturbance of SHD. When dobutamine was administered and the instillation rate was trebled in PDB group, SHD and OTC were maintained in a favorable state. It is concluded that PDB, administration of dobutamine and sufficient instillation are advantageous to maintain systemic hemodynamic stability during the anhepatic phase of orthotopic liver transplantation. 相似文献
78.
T Hasegawa M Nadai T Kuzuya I Muraoka R Apichartpichean K Takagi K Miyamoto 《The Journal of pharmacy and pharmacology》1990,42(11):767-772
To clarify the mechanism of interaction between theophylline and enoxacin, the effects of enoxacin and its metabolite, 4-oxo-enoxacin, on the disposition of new xanthine derivatives, 1-methyl-3-propylxanthine (MPX) and 3-propylxanthine (enprofylline), as models of theophylline have been investigated in rats. Pretreatment with enoxacin significantly delayed the elimination of MPX from plasma. No significant change in the volume of distribution of MPX was observed in the presence of enoxacin, but the total body clearance of MPX was significantly decreased by approximately 60 and 80% after pretreatment with 25 and 100 mg kg-1 of enoxacin, respectively. The amount of the decrease in total body clearance depended on the dose of enoxacin. 4-Oxo-enoxacin had little or no effect on MPX disposition. A newly developed quinolone, NY-198, which does not affect the disposition of theophylline, also did not affect the disposition of MPX. Enoxacin also had no effect on the disposition of enprofylline. These results indicate that the mechanism for decrease in theophylline clearance induced by enoxacin may not be due to its metabolite, 4-oxo-enoxacin, but to enoxacin itself, and that enoxacin does not inhibit solely the elimination process depending on cytochrome P450 isoenzyme for N-demethylation. It is likely that enoxacin has no influence on the renal excretion of xanthines. 相似文献
79.
Takao Hattori MD Toshihiro Hirai Minoru Niimoto Tetsuya Toge Yukihisa Miyoshi Tatsuya Yoshihara Sunao Otagaki Yoshinori Yamashita 《Surgery today》1986,16(2):90-97
Transabdominal resection for esophagocardial cancer and reestablishment of alimentary continuity using bypass methods were
performed in 76 patients. Thirteen underwent a bypass with a gastric tube and in 30, a colonic segment was prepared. In the
remaining 33, a jejunal segment was used as a bypass organ, with considerable success. The 5 year survival rates were 68.8
per cent in those with stages (I+II), 16.5 per cent in those with stage III, 12.6 per cent in those with stage IV and 22.5
per cent in all cases, indicating similar results compared to those with cancer located in the upper third of the stomach
with the limited proximal extension within the esophagocardial junction and operated on during the same period. 相似文献
80.
T. Kobayashi F.A. Neethling S. Taniguchi Y. Ye M. Niekrasz E. Koren W.W. Hancock H. Takagi D.K.C. Cooper 《Xenotransplantation》1996,3(3):237-245
Abstract: We examined whether hyperacute rejection (HAR) of a discordant xenograft in a nonhuman primate model could be inhibited by the anticomplement agents, FUT-175 (FUT) and K76COOH (K76). The inhibitory effect of FUT and K76 on baboon sera was studied in vitro by i) complement-mediated hemolysis of sheep erythrocytes (by measuring serum CH50) and ii) cytotoxicity to cultured pig kidney (PK15) cells. The in vivo administration of FUT (at 0.2–25 mg/kg/h i.v. continuously) and K76 (50 mg/kg i.v. bolus) allowed evaluation of the serum levels of these drugs. Both FUT and K76 inhibited serum CH50 in a concentration-dependent manner. An enhanced effect was obtained by combining K76 with FUT therapy. High concentrations of FUT (>10-4 M) and K76 (>103 μxg/ml) were necessary to suppress serum CH50 to <5% of the normal level. However, PK15 cytotoxicity remained at >50% in the presence of i) 10-4 M of FUT, ii) 103 μg/ml of K76, and iii) 10-6 M of FUT + 103 μg/ml of K76. Pig heart transplantation (HTX) was performed in two baboons receiving FUT (1 mg/kg/h i.v. continuously) and K76 (at 200 mg/kg ×1 or 400 mg/kg + 200 mg/kg × 2 i.v, respectively). Cytotoxicity of the serum to PK15 cells at the time of HTX showed 39% and 1% cell death, respectively, in these two baboons, and the CH50 level was 1% (of control level) and 0%, respectively. Graft survival was 4.5 hours and 10 hours (with death of the baboon), respectively (compared with a mean of 29 minutes in control experiments). Both excised grafts showed typical features of hyperacute rejection. Immunopathological studies revealed deposition of C1q, C3d, C6, properdin, and Factor B, demonstrating that complement activation was not fully inhibited by FUT and K76. We conclude that i) FUT and K76 are indeed potent complement inhibitors, ii) the dosages of FUT and K76 necessary to suppress complement-mediated injury cannot be extrapolated from previously reported data obtained from serum CH50 levels, and iii) higher (possibly toxic) dosages will be required to inhibit complement activation completely. It seems unlikely that HAR will be prevented by these drugs alone, although they may be beneficial when combined with other forms of therapy. 相似文献