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11.
12.
Development of autoimmune insulitis is prevented in E alpha d but not in A beta k NOD transgenic mice 总被引:4,自引:0,他引:4
M Uehira M Uno T Kürner H Kikutani K Mori T Inomoto T Uede J Miyazaki H Nishimoto T Kishimoto 《International immunology》1989,1(2):209-213
Two lines of E alpha d-expressing NOD mice were established by continuously backcrossing [E alpha d B6 transgenic mice x NOD] F1 to parental NOD or directly microinjecting the E alpha d gene into fertilized NOD eggs. Similarly, A beta k-expressing transgenic NOD mice were produced. Subsequent histological examination of pancreatic tissues revealed that autoimmune insulitis was prevented in E alpha d backcross and transgenic mice but not in A beta k transgenic mice. 相似文献
13.
Nakamura Y Nishimoto K Akamatu M Takahashi M Maruyama A 《Electromyography and clinical neurophysiology》1999,39(2):71-74
Physical exercise has beneficial effects not only on cardiovascular system and fat metabolism, may also directly effect the cognitive process. We studied the effect of physical exercise on cognitive processes by measuring the P300 event related-potential (ERP) after jogging. Seven well-trained joggers were enrolled in this study and the P300 potentials using auditory oddball paradigm. ERPs were measured before and after 30 minutes of jogging. The amplitude of the P300 significantly increased after jogging compared to values recorded before jogging. These findings suggest that jogging has the effect of facilitating cognitive processes involved in generation of the P300. 相似文献
14.
15.
Koshiro Sugita Satoshi Ibara Toshio Harumatsu Chie Ishihara Yoshiki Naito Masakazu Murakami Seiro Machigashira Hiroyuki Noguchi Mitsuru Muto Makoto Matsukubo Satoshi Ieiri 《Journal of pediatric surgery》2021,56(7):1121-1126
Purpose: We aimed to investigate potential predictors of focal intestinal perforation (FIP) in extremely low birth weight infants (ELBWIs) among coagulation and fibrinolysis markers at birth.Methods: We reviewed the medical records of FIP patients and their coagulation and fibrinolysis markers at birth between 2010 and 2019, and matched patients according to gestational age. FIP was diagnosed based on macroscopic intestinal perforation with a punched-out lesion without necrosis. Patient characteristics and blood test results, including coagulation and fibrinolysis marker levels, were compared between the groups.Results: Two hundred forty ELBWIs were enrolled in this study (FIP, n = 18; controls, n = 222). In the FIP group, the gestational age at birth was significantly younger (p = 0.023) and the birth weight was significantly lower (p = 0.007) in comparison to the control group. Furthermore, the FIP group showed significantly lower levels of fibrinogen (p = 0.027) and factor XIII (F-XIII) (p = 0.007). The receiver operating characteristics curves for fibrinogen and F-XIII revealed that the 95% confidence intervals of fibrinogen and F-XIII were 0.530–0.783 (p = 0.027), and 0.574–0.822 (p = 0.007), respectively.Conclusions: This is the first report focusing on coagulation and fibrinolysis markers in FIP patients at birth. The fibrinogen and F-XIII values at birth are potential predictors of FIP in ELBWIs.Type of Study: Study of Diagnostic Test (Case Control Study)Level of Evidence: Level IV 相似文献
16.
K Kunishio N Mishima T Matsuhisa K Tsuno N Matsumi T Satoh K Matsumoto T Furuta A Nishimoto T Shiraishi 《Journal of neurosurgery》1990,72(2):268-272
The proliferative capacity of brain-tumor cells was analyzed in vitro and in situ using monoclonal antibody (MAb) against deoxyribonucleic acid (DNA) polymerase alpha. For the in vitro studies, two cultured human glioma cell lines were investigated using MAb against DNA polymerase alpha, the MAb Ki-67, a serum against proliferating cell nuclear antigen (PCNA/cyclin), bromodeoxyuridine (BUdR), and an anti-BUdR MAb. During exponential growth of the cells, the percentage of polymerase alpha-positive cells (the "polymerase alpha score") ranged from 72.0% to 77.1%, the Ki-67-positive cells (the "Ki-67 score") ranged from 43.4% to 59.4%, the PCNA/cyclin-positive cells from 30.9% to 41.4%, and the BUdR labeling index from 28.6% to 39.3%. For the in situ studies, tissue from 60 human brain tumors and from two normal human brains was investigated and the polymerase alpha scores and Ki-67 scores were compared. In normal brain tissue, no immunostaining was found by either method. In brain tumors, both the polymerase alpha scores and the Ki-67 scores correlated with the histological grade of malignancy. Polymerase alpha scores were generally higher than Ki-67 scores in the same specimen, especially in malignant brain tumors. These findings suggest that immunostaining of DNA polymerase alpha is a convenient and important new method by which to estimate the cellular proliferation rate of brain tumors. Polymerase alpha scores may be closer to the growth fraction of the individual tumor than the MAb Ki-67 or other scores. 相似文献
17.
Pharmacokinetics and safety of Z-321, a novel specific orally active prolyl endopeptidase inhibitor, in healthy male volunteers 总被引:1,自引:0,他引:1
Umemura K Kondo K Ikeda Y Nishimoto M Hiraga Y Yoshida Y Nakashima M 《Journal of clinical pharmacology》1999,39(5):462-470
This study investigates the pharmacokinetics and safety profile of Z-321, (4R)-3-(indan-2-ylacetyl)-4-(1-pyrrolidinyl-carbonyl)-1,3-thiazoli dine, a novel specific orally active prolyl endopeptidase (PEP) inhibitor. Following a preliminary safety evaluation wherein 2 subjects received 3.75 and 15 mg doses and 2 other subjects received 7.5 and 30 mg doses, 16 subjects were assigned to two groups of 8 subjects each. In each group, 6 subjects were to receive active treatment, and 1 or 2 subjects were to receive placebo treatment. One group received 60 mg under fasted and fed conditions. A separate group of 8 subjects received 60 mg of Z-321 or a placebo in a bid regimen for 6 days and the morning dose on day 7. The concentrations of Z-321 and its main metabolites--R- and S-sulfoxide; RR-, SS-, and RS-indanol; and indanolsulfoxides in plasma and urine--were determined by the HPLC method. In the multiple-dose study, the cholinesterase activity was gradually increased and reached above the normal range on day 8 in 3 of 6 subjects given Z-321 and gradually returned to the normal range after completion of dosing. The elevation of plasma cholinesterase activity was considered to be an action of Z-321, but this remains to be verified. In a single-dose study at a dose of 30 mg, headache and vomiting were observed in 1 of 6 subjects. In the multiple-dose study, slight skin itching and eczema in 3 and 2 of 6 subjects, respectively, and headache in 2 of 6 subjects were observed, but all symptoms were not severe. There were no other abnormal findings in objective signs and laboratory findings, including blood pressure, heart rate, electrocardiogram, body temperature, hematology, blood chemistry, and urinalysis. The Cmax of Z-321 at 30, 60, and 120 mg in the fasting state were 63.7 +/- 23.9, 102.0 +/- 43.1, and 543.3 +/- 437.0 ng/ml (mean +/- SD), respectively, at 0.9 hours after administration, and the t1/2 was about 1.8 hours. There were no dramatic changes in the pharmacokinetics of Z-321 in the presence of food. In the multiple-dose study, there was no drug accumulation trend in plasma. These results indicate that Z-321 has acceptable pharmacodynamic and pharmacokinetics profiles for clinical use without any serious adverse events, as verified in healthy young male volunteers. 相似文献
18.
Tohru Ozaki Toshihiko Uematsu Satoru Nagashima Masahiko Nishimoto Mitsuyoshi Nakashima 《Naunyn-Schmiedeberg's archives of pharmacology》1991,344(4):478-487
Summary DPI 201-106 (DPI), a novel and potent cardiotonic agent, exhibits its effects by prolonging the open state of Na+ channels, resulting in an increase in action potential duration, and thus, is supposed to share the class III antiarrhythmic activity. The effects of DPI on the hemodynamics, intraventricular conduction and refractoriness of heart, and the incidence of arrhythmias induced by programmed electrical ventricular stimulation (PES) were compared with (±)-dobutamine. Dogs which survived for 5 to 7 days after the induction of myocardial infarction were used as the model. The presence of sub-acute myocardial infarction caused by occluding the left anterior descending coronary artery elicited a mild left ventricular dysfunction represented by a significant decrease in peak LV dp/dt by about 20%.Both i.v. bolus injection of DPI (1, 3 and 5 mg/kg) and i. v. continuous infusion of dobutamine (3, 5 and 10 g/kg/min), which were administered in a cumulative manner, dose-dependently improved the hemodynamic parameters. At the higher doses of both DPI (3 and 5 mg/kg) and dobutamine (5 and 10 g/kg/min) the control values were reached or even exceeded. DPI dose-dependently increased the effective refractory period (ERP) of both non-infarcted and infarcted ventricular myocardia to a similar degree, but the conduction time showed a frequency-dependent increase in the infarcted myocardium to a greater degree than in the non-infarcted myocardium after DPI. In contrast, dobutamine decreased the ERP in both non-infarcted and infarcted myocardia, and slightly increased the difference of refractoriness between the non-infarcted and infarcted zones with no effect on the intraventricular conduction. In the PES study, DPI (3 and 5 mg/kg) produced a significant decrease in the incidence of ventricular tachycardia, whereas dobutamine (5 and 10 g/kg/min) tended to worsen the arrhythmias. These findings suggest that cardiotonic agents with a class III antiarrhythmic property such as DPI may be potentially useful for the management of heart failure accompanied by ischemic heart disease.Abbreviations DPI, DPI 201-106; PES
programmed electrical ventricular stimulation
- LV dp/dt
the rate of rise of left ventricular pressure
- ERP
effective refractory period
- RVOT
right ventricular outflow tract
- VT
ventricular tachycardia
- LAD
left anterior discending coronary artery
Send offprint requests to T. Uematsu at the above address 相似文献
19.
MR findings of posterior fossa hemangioblastomas. 总被引:1,自引:0,他引:1
S Asari S Katayama T Itoh S Tsuchida A Nishimoto 《Computerized medical imaging and graphics》1992,16(2):131-135
MR findings of five posterior fossa hemangioblastomas were reported. In the cystic type, a cyst was low intensity on T1WI and high intensity on T2WI. Mural nodule was clearly enhanced by Gd-DTPA. In the solid type, the tumor was shown as an isointense lesion on T1WI and as high intensity on T2WI, but it was markedly and homogeneously enhanced by Gd-DTPA. Multiple extremely low-intensity serpentine "flow void" signs, indicating afferent and efferent vessels, were observed within or around the tumor. These were characteristic pictures in this tumor. 相似文献
20.
Hiroaki Okamoto Akira Nagatomo Hideo Kunitoh Hiroshi Kunikane Koshiro Watanabe 《Cancer chemotherapy and pharmacology》1998,42(4):307-312
Purpose: Carboplatin doses can be individualized using the formula of Calvert et al. (Calvert formula) dose (mg) = area under the
plasma concentration versus time curve (AUC) · [glomerular filtration rate (GFR) + 25]. Creatinine clearance (Ccr), either
measured by the 24-h method or calculated by the formula of Cockcroft and Gault [Cockcroft-Gault (CG) formula], is often substituted
for the GFR. The CG formula is based on patient weight, age and sex, and the serum creatinine (Cr) concentration. Another
method for predicting carboplatin clearance (CL) using patient characteristics has also been proposed by Chatelut et al. (Chatelut
formula). This study was undertaken to evaluate the performance of the three formulae in predicting standard- and low-dose
carboplatin pharmacokinetics. Methods: A total of 52 patients with advanced lung cancer were enrolled in this pharmacokinetic study; 37 received standard-dose
carboplatin and 25 received low-dose carboplatin. The Cr concentration was measured using an enzymatic assay. The three formulae
were used to predict carboplatin CL. The median absolute percent error (MAPE) for each formula was evaluated by comparing
the calculated and observed CL. For comparison of AUCs, free platinum plasma concentrations were measured at intervals up
to 24 h after carboplatin administration. AUCs were determined and compared with predicted values. Results: In the standard-dose carboplatin group, the MAPEs for the prediction of carboplatin CL from the 24-h Calvert, CG-Calvert
and Chatelut formulae were 13%, 12% and 23%, respectively. In the low-dose carboplatin group, the corresponding MAPEs were
27%, 18% and 44%, respectively. Observed standard-dose carboplatin AUCs after aiming for target AUCs of 5 and 6 mg · min/ml
using the Calvert formula based upon the 24-h Ccr were 5.3 ± 0.8 and 5.9 ± 0.8, respectively, indicating a small and acceptable
bias compared with that predicted from the dosing formula. Conclusions: The pharmacokinetics of standard-dose carboplatin were accurately predicted by the Calvert formula based upon either 24-h
or CG-calculated Ccr, but not by the Chatelut formula. Either CG-calculated or 24-h Ccr can be substituted for the GFR in
the Calvert formula for the determination of individual doses. The poor predictability of the Chatelut formula found in this
study might be the result of a differences in either the Cr assay or the patient population. Therefore, formulae which attempt
to estimate GFR are not necessarily valid if either the Cr assay or the patient population is changed.
Received: 23 July 1997 / Accepted: 16 December 1997 相似文献