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91.
H Masuda M Hirai Y Ohtawara A Tajima Y Aso 《Nihon Hinyōkika Gakkai zasshi. The japanese journal of urology》1990,81(4):577-582
Rats with bladder tumor induced by BBN were treated by intravesical instillation of 0.8 mg of (2"R)-4'-O-tetrahydropyranyladriamycin (THP) (9 rats) or adriamycin (ADM) (8 rats) dissolved in 0.2 ml of distilled water. Thirty minutes later, the bladder was removed surgically. Rats without the tumor received the same treatment of THP (8 rats) or ADM (9 rats). THP and ADM infiltrations to the normal bladder tissue and the tumor were estimated by the use of the photonic microscope system, since both drugs were known to emit characteristic fluorescence. It was found that infiltration of THP to the tumor tissue was more prominent in amounts and deeper than that of ADM, while smaller amounts of THP infiltrated into the normal mucosa compared to ADM. The fact might explain the clinical finding that THP instilled intravesically in half a concentration of ADM showed the same effect on the tumor as ADM. Subsequently, tissue concentrations of THP and ADM were estimated by high performance liquid chromatography. Either THP or ADM was instilled intravesically for 30 minutes to 6 rats with bladder tumor. Similarly, either THP or ADM was instilled in 5 rats without the tumors. Contrary to the result of the photonic microscope system, the tissue concentration of THP was not different from that of ADM not only in the tumor tissues but also in the normal bladder ones. Furthermore, the tissue concentration of both drugs in the normal bladder was higher than that in the bladder tumor.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
92.
The dose-response relation of pipecuronium, the time course of its neuromuscular blocking effects, and the reversibility of the residual block by neostigmine have been investigated in patients under sevoflurane/N2O Anesthesia using a neuromuscular transmission analyzer (Accelograph®, Biometer, Denmark). After an initial dose of pipecuronium (0.04mg·kg–1, i.v.), the maximum block rate, onset time, the time from administration until 25% recovery and 50% recovery of control twitch height of the first response to train-of-four nerve stimulation and the interval time of administration of maintenance dose (0.005mg·kg–1, i.v.) were 93.7 ± 7.68%, 5.0 ± 1.84, 55.4 ± 23.92, 73.0 ± 29.44 and 38.7 ± 15.50 minutes, respectively. The average intubation score (excellent; 0, good; 1 fair; 2, poor; 3) was 0.63 ± 0.56 at the level of 95.88 ± 5.06% block. Neostigmine (1.5mg) promptly reversed the residual neuromuscular blockade induced by pipecuronium (reversal time: 10.1 ± 2.98 minutes). No side effects attributable to pipecuronium was seen in this study.In conclusion, pipecuronium is a very useful nondepolarizing neuromuscular blocking agent especially for moderately long surgical procedure over 4–5 hours.(Ueda N, Masuda Y, Muteki T, et al.: Does-response relation and time course of action of pipecuronium in patients anesthetized with nitrous oxide and sevoflurane. J Anesth 7: 151–156, 1993) 相似文献
93.
John J. Ryan Dan Levesque Luz G. Panopio Wing F. Sun Yoshito Masuda Hiroaki Kuroki 《Archives of environmental contamination and toxicology》1993,24(4):504-512
The pharmacokinetics of polychlorinated dibenzofurans (PCDFs) and polychlorinated biphenyls (PCBs) in humans was studied by monitoring the blood concentrations of individuals who ingested a contaminated rice oil in Japan (yusho) in 1968 and in Taiwan (yu-cheng) in 1979. Sixteen yusho patients were followed from 1982 to 1990 and three yu-cheng individuals from 1980 to 1989. From the three yucheng patients, blood lipid values for the two persistent toxic congeners, 2,3,4,7,8-pentachlorodibenzofuran (PnCDF) and 1,2,3,4,7,8-hexachlorodibenzofuran (HxCDF), varied from 50 g/kg at first sampling to about 1 g/kg at last sampling corresponding to half-lives for elimination (t1/2) of 2-21/2 years. The blood lipid values for the same PCDF congeners in yusho patients varied from 5 g/kg down to 0.1 g/kg. The calculated t1/2 were more variable with median values closer to 10 years. Planar PCBs #126 and #169 were present at lower concentrations than the PCDFs. For seven of the other PCB congeners, half-lives for elimination in the yu-cheng individuals varied from 1.2 up to 4.6 yr depending on the degree of chlorination. For the yusho patients, the elimination for the PCBs was longer. These results show that clearance of the toxic PCDFs and PCBs in humans is non-linear with faster elimination at higher exposure followed by slower decreases as background levels are approached. Such a clearance pattern can best be explained by a two compartment liver and fat pharmacokinetic model. 相似文献
94.
Ohno A Hirashima T Kubo A Masuda N Takada M Fujiwara H Yasumitsu T Kikui M Fukuoka M Nakagawa K 《International journal of oncology》1997,10(3):521-528
To investigate the role of p53 abnormalities in predicting the survival of patients with non-small cell lung cancer (NSCLC), polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and immunohistochemical analyses were performed on 74 and 67 tumor samples, respectively, from patients with pathological stage I-IIIa NSCLC. An abnormally migrating SSCP band was observed in 21 of 74 (28%) tumor specimens. DNA sequence analysis revealed 23 intragenic mutations including 3 small deletions and 20 point mutations. Immunohistochemical analysis using the DO-7 monoclonal antibody showed abnormal expression of p53 in 27 of 67 (40%) patients. The concordance rate between immunohistochemical and PCRSSCP analyses was 73% (49/67) in this study. Univariate and multivariate analyses demonstrated that abnormal expression of p53 may be associated with prolonged survival (p=0.0997 and 0.0099, respectively). In contrast, no relationship was observed between p53 mutation and overall survival (0.6968). These results suggest that p53 status and the survival outcome changes between immunohistochemical and mutational analyses in stage I-IIIa NSCLC. 相似文献
95.
Lee K Suei Y Yamada T Masuda S Ogawa I Tanimoto K 《Dento maxillo facial radiology》1999,28(6):375-377
Malignant tumors of the paranasal sinuses are rare: about 80% are found in the maxillary sinus123. The presence of dense radiopaque masses in combination with destruction of the bone margins suggests osteosarcoma or aspergillosis4 rather than carcinoma. We present a unique mucoepidermoid carcinoma of the maxillary antrum containing new bone formation and discuss the differential diagnosis. 相似文献
96.
Tanaka M Kinukawa N Akazawa K Abe S Itoh K Imai K Masuda T Nakamura M 《Medicine and science in sports and exercise》1999,31(12):1709-1713
PURPOSE: The purpose of this study is to determine the optimum period and kind of exercise which are more effective for increasing the calcaneus osteo sono assessment index (OSI) in adolescent women. METHODS: The subjects consisted of 600 female students aged from 19 to 21 studying at the Department of Food and Nutrition at Nakamura Gakuen University. The calcaneus OSI was measured by ultrasonic bone absorptiometry. The factors associated with an increased OSI were determined using piecewise linear regression analyses. RESULTS: Experience in performing impact-loading exercise either in junior high school or high school was found to be a significant predictive factor for increased calcaneus OSI after adjusting for age and weight. Regarding other exercise-related factors such as subjective intensity, frequency, hours at a time, and total duration of exercise, a piecewise liner regression analysis showed that a total duration of over 7 yr and a high subjective intensity of the impact-loading exercise during high school and junior high school periods caused a significant increase in the calcaneus OSI. However, the OSI decreased when the subjective intensity of the impact-loading exercise during the high school period was reported to be "very strenuous." CONCLUSIONS: Impact-loading exercise in junior high school and high school is important for increasing calcaneus OSI; however, impact-loading exercise in high school with a "very strenuous" subjective intensity was also found to possibly decrease the calcaneus OSI. 相似文献
97.
Pseudolesions of the liver possibly caused by focal rib compression: analysis based on hemodynamic change 总被引:2,自引:0,他引:2
Yoshimitsu K Honda H Kuroiwa T Irie H Tajima T Jimi M Masuda K 《AJR. American journal of roentgenology》1999,172(3):645-649
OBJECTIVE: The purpose of this study is to show and analyze the CT appearance of pseudolesions of the liver caused by rib compression and to discuss the possible mechanism on the basis of findings of incremental dynamic CT, CT during arterial portography, and CT hepatic arteriography. CONCLUSION: Focal compression of the liver caused by curved ribs can cause transient focal diminishment of portal venous perfusion without significantly altering hepatic arterial perfusion. Such diminishment may be observed as low-density areas on the early phase of incremental dynamic CT. 相似文献
98.
Hepatic angiomyolipoma: report of changing size and internal composition on follow-up examination in two cases 总被引:4,自引:0,他引:4
Irie H Honda H Kuroiwa T Yoshimitsu K Tajima T Jimi M Shimada M Taguchi K Masuda K 《Journal of computer assisted tomography》1999,23(2):310-313
We present two cases of hepatic angiomyolipoma in which the size and internal composition of the tumor changed during the course of follow-up study. The tissue elements composing the tumor are thought to grow or regress independently during the disease's clinical course. Radiologists should be aware that hepatic angiomyolipoma can change in size and internal composition during its natural course. 相似文献
99.
Yoshimitsu K Honda H Kuroiwa T Irie H Tajima T Jimi M Kuroiwa K Naito S Masuda K 《Journal of magnetic resonance imaging : JMRI》1999,9(4):579-585
We attempted to determine whether cytoplasmic fat in clear cell renal cell carcinoma (RCC) can be identified by chemical shift gradient-echo magnetic resonance imaging (CSI). CSI was performed for 22 clear cell RCCs and 30 other renal tumors (including 16 non-clear cell RCCs), all of which were surgically proven. Signal reduction in out-of-phase images of these tumors was retrospectively evaluated and compared. The signal loss ratio (SLR) was defined and calculated. Fat staining of specimens from 16 tumors was performed and correlated with SLR. SLR was significantly higher in clear cell RCCs than in non-clear cell RCCs (P < 0.001). There was a significant correlation between degree of fat staining positivity of the specimens and SLR (P < 0.01). When signal reduction in out-of-phase images suggested the diagnosis of clear cell RCC, correct diagnosis of this entity was made in resected renal tumors with sensitivity, specificity, and accuracy of 82%, 90%, and 87%, respectively. CSI can demonstrate cytoplasmic fat in clear cell RCCs, which helps to differentiate this entity from other RCCs. 相似文献
100.
Kura N Kihara K Masuda H Tsujii T Oshima H 《Hinyokika kiyo. Acta urologica Japonica》1999,45(1):45-48
We report a case of a huge retroperitoneal tumor in a 67-year-old woman. When the patient was taken to another hospital by ambulance, she had lost consciousness because of hypertension and hypoglycemia and abdominal CT revealed a huge retroperitoneal tumor with deviation of the right kidney and inferior vena cava. After further examinations including ultrasonography, MRI and angiography in our hospital, the tumor was extirpated. The tumor, 22 x 17 x 10 cm in size and 2,580 g in weight was diagnosed as hemangiopericytoma histologically. She has remained well with no evidence of recurrence for 9 months since the operation. 相似文献