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61.
Shinichi Izuchi Tohru Terachi Masahiro Sakamoto Tetsuo Mikami Mamoru Sugita 《Current genetics》1990,18(3):239-243
Summary The nucleotide sequences of tRNAAsn (GUU) and tRNATyr (GUA) genes from tomato mitochondria and their flanking regions have been determined. The tomato mitochondrial tRNAAsn gene is located 2.1 kb downstream from the tRNACys gene reported previously (Izuchi and Sugita 1989) and shows a nearly complete identity with the corresponding chloroplast gene. The tRNATyr gene, which shows only 73% homology with the corresponding chloroplast gene, has to be considered a native mitochondrial tRNA gene and is 535 bp from the chloroplast-like tRNAAsn gene on the same strand. Northern hybridization analysis revealed that the three tRNA genes are transcribed in tomato mitochondria. Southern hybridization analysis of tomato, sugar beet, rice and wheat mitochondrial DNAs, with oligonucleotide probes for mitochondrial or chloroplast tRNA genes, demonstrated that the mitochondrial tRNACys gene found in tomato is present in dicot plants but not in monocots. On the other hand, a chloroplast-like tRNACys gene exists in monocot plants. 相似文献
62.
Twenty-five patients who required mechanical ventilatory support (MVS) after major surgery or severe burns were studied to determine whether airway occlusion pressure (P0.1) is a clinically useful indicator to predict the success or failure of the weaning trial. A total of 33 weaning trials were attempted on these patients. Of the 33 trials, 24 were followed by successful weaning and 9 by failure. Although the success group, when compared with the failure group, had a lower respiratory rate (P 0.001), a lower minute ventilation (P 0.001), a higher maximal voluntary ventilation to minute ventilation ratio (P 0.01) and a higher forced vital capacity (P 0.05), no threshold values separated the success from the failure group. The alveolar-arterial PO
2 gradient, with an Fi
O
2 of 1.0, in weaning success and failure showed no statistical difference. In contrast, all patients in the success group had a P0.1 of less than 3.5cmH2O and those in the failure group had a P0.1 of greater than 3.5cmH2O (P 0.001). We conclude that P0.1 is a clinically superior indicator for discontinuing MVS in patients with acute respiratory failure.(Okamoto K, Sato T, Morioka T: Airway occlusion pressure (P0.1)—A useful predictor for the weaning outcome in patients with acute respiratory failure—. J Anesth 4: 95–101, 1990) 相似文献
63.
We evaluated the reliability of conventional weaning criteria from a ventilator during 33 weaning trials on 25 patients with acute respiratory failure (ARF). Of 13 criteria, a ratio of maximal voluntary ventilation to minute ventilation (MV) 2, a vital capacity 12ml·kg–1, a spontaneous respiratory rate 25 breaths·min–1, and a MV 10l·min–1 appeared to be useful for predicting successful weaning outcome. However, even using those criteria, there were many falsely-negative cases. The alveolar-arterial PO
2 gradient 350mmHg at an Fi
O
2 1.0 was not useful as a predictor of weaning outcome. The present study demonstrates that conventional criteria are frequently inaccurate for predicting weaning outcomes and suggests that the use of some of these criteria may unnecessarily prolong the length of ventilator support. Since ventilation of most patients with poor oxygenation can be successfully discontinued by placing them on a continuous positive airway pressure system, these results suggest that the improvement of oxygenation is not an indispensable prerequisite for weaning from mechanical ventilators.(Okamoto K, Iwamasa H, Dogomori H, et al.: Evaluation of conventional weaning criteria in patients with acute respiratory failure. J Anesth 4: 213–218, 1990) 相似文献
64.
Sakuragi T Fujiwara K Akashi-Tanaka S Tsuda H Fukutomi T 《Breast cancer (Tokyo, Japan)》1997,4(1):53-56
Dermatofibrosarcoma protuberans (DFSP) is a slow-growing but locally aggressive, fibrous tumor that has a high rate of local
recurrence after surgical resection. This tumor occurs most commonly in the trunk and proximal extremities. In this report
we present a case of dermatofibrosarcoma protuberans in the skin over the breast which was re-excised after pathological diagnosis,
considering cosmetic aspects. Only three other cases of dermatofibrosarcoma protuberans of the anterior chest wall have been
encountered in our hospital, and all of these cases were male. The presence of this tumor in the skin over the breast appears
to be rare in females. Careful complete resection is recommended for this type of tumor. 相似文献
65.
Motomaru Masutani Akira Mizoguchi Tohru Arii Tadaaki Iwasaki Chizuka Ide 《Journal of neurocytology》1994,23(12):811-819
Summary The localization of protein kinase C (PKC) , and subspecies in sensory axon terminals of muscle spindles in the plantar lumbrical muscles of rat was investigated by light and electron microscopic immunocytochemistry using monoclonal and polyclonal antibodies. Immunoreactivity for these subspecies was detected specifically in sensory axon terminals which wound spirally around the intrafusal muscle fibres of the muscle spindle. Immunostaining was found to be stronger with polyclonal than with monoclonal antibodies. By electron microscopy, immunoreactivity for , and subspecies was almost diffusely distributed in the cytoplasm of the axon terminal, and the overall pattern of distribution of immunoreactivity was similar for all three subspecies. In the cases of a and subspecies, some intensely immunostained regions were found in the cytoplasm, but no definite subcellular structures corresponding to such regions could be identified. Considering that PKC plays a crucial role in the regulation of ion channels, it is suggested that PKC might be involved in the control of mechanoelectric transduction in sensory axon terminals. 相似文献
66.
Shiomi H Hase T Matsuno S Izumi M Tatsuta T Ito F Kishida A Tani T Kodama M 《Surgery today》1999,29(12):1280-1284
An 18-year-old male was admitted to our Emergency Department with a traumatic abdominal wall hernia (TAWH) of the left lower
quadrant (LLQ) after suffering hypogastric blunt injury and urogenital lacerations in a motorcycle accident. Upright chest
X-ray showed a small amount of right infradiaphragmatic free air, and a computed tomographic (CT) scan demonstrated an abdominal
wall hernia. At surgery, no impairment was found in the digestive tract, and an abdominal herniorrhaphy was performed. It
is suggested that the free air had passed through a connection between the scrotal laceration and the contralateral abdominal
defect via the subcutaneous space and was palpated as emphysema. This is a new type of TAWH, which suggests that blunt abdominal
trauma may result in negative pressure in the subcutaneous and peritoneal cavity, and this could reflect the pathophysiology
of TAWH. 相似文献
67.
Tohru Ide Tetsuo Kochi Kazuhiko Iijima Tadanobu Mizuguchi 《Journal canadien d'anesthésie》1996,43(1):44-49
Purpose
The purpose of this study was to determine the effect of increasing the concentrations of sévoflurane anaesthesia on the distribution of diaphragm blood flow (Qdi) in ten dogs during mechanical ventilation.Methods
Animals were divided into two groups, sévoflurane (n = 6) and time control (n = 4) groups. Blood flow to the crural and the costal diaphragm (Qcru, Qcost) was determined by the hydrogen clearance technique at 0, 0.5, 1.0 and 1.5 minimum alveolar concentration (MAC) of sévoflurane after a 30 min period of steady-state conditions. Cardiac output (CO) and the mean arterial blood pressure (MBP) were also measured.Results
Sevoflurane anaesthesia caused a reduction in CO (L · min?1) from a control value of 1.51 ± 0.21 to 1.38 ±0.1 (0.5 MAC), 1.09 ± 0.15 (1.0 MAC) and 0.98 ± 0.12 (1.5 MAC) (Mean ± SD). Mean blood pressure, Qcru and Qcost also decreased with increasing depth of anaesthesia. In addition, the decrease of Qcru was greater than that of Qcost at all levels of MBP and CO. No change occurred in these variables in the lime control group.Conclusion
Sevoflurane anaesthesia changes the distribution of Qdi with a greater reduction occurring in Qcru than in Qcost. 相似文献68.
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
69.
Penetration of etoposide into human malignant brain tumors after intravenous and oral administration
Katsuzo Kiya Tohru Uozumi Hidenori Ogasawara Kazuhiko Sugiyama Takuhiro Hotta Takashi Mikami Kaoru Kurisu 《Cancer chemotherapy and pharmacology》1992,29(5):339-342
Summary Penetration of etoposide into the cerebrospinal fluid, brain tumor, and brain tissue after intravenous administration was investigated in patients presenting with malignant brain tumors. A relatively low dose (55–65 mg/m2) was used to compare intravenous with oral administration. High-performance liquid chromatography with fluorescence detection was used to evaluate drug levels. Plasma and cerebrospinal fluid levels of etoposide after oral administration (50–150 mg/day) were also studied so as to determine the adequate oral dose for the treatment of malignant brain tumors. The peak plasma concentration after intravenous administration ranged from 7.01 to 10.47 g/ml, varying in proportion to the injected dose, whereas that after oral administration was lower, namely, 1.44–4.99 g/ml, and was unstable when the oral dose was 150 mg daily. The peak cerebrospinal fluid level following either intravenous or oral administration was much lower than the plasma concentration and was influenced by the peak plasma level and the sampling site. The etoposide concentration in cerebrospinal fluid taken from the subarachnoid space and ventricle of patients displaying no tumor invasion and of those presenting with meningeal carcinomatosis and in cerebrospinal fluid taken from the dead space after tumor resection was 0.7%±0.5%, 3.4%±1.0%, and 7.2% ± 8.5%, respectively, of the plasma concentration. Serial oral administration did not result in the accumulation of etoposide in cerebrospinal fluid. The tumor concentration (1.04–4.80 g/g) was 14.0%±2.9% of the plasma level after intravenous administration, was related to the injected dose, and was approximately twice the concentration detected in the brain tissue. Therefore, a relatively low dose of etoposide injected intravenously penetrates the brain tumor at an efficacious concentration. Our results indicate than an oral dose of 100 mg etoposide be given for malignant brain tumors, as limited penetration of the drug into the intracranial region was observed. 相似文献
70.
Akio Kanetoshi Eiji Katsura Hiroshi Ogawa Tohru Ohyama Hiroyasu Kaneshima Toshiaki Miura 《Archives of environmental contamination and toxicology》1992,23(1):91-98
Acute toxicity of 2,4,4-trichloro-2-hydroxydiphenyl ether (Irgasan® DP300) (I) and its three chlorinated derivatives, 2,3,4,4-tetrachloro-2-hydroxydiphenyl ether (II), 2,4,4,5-tetrachloro-2-hydroxydiphenyl ether (III) and 2,3,4,4,5-pentachloro-2-hydroxydiphenyl ether (IV), in mice were examined by intraperitoneal injection. The LD50 values of Irgasan DP300, II, III and IV were 1,090, 710, 650 and 430 mg/kg, respectively.The percutaneous absorptions of these tritiated compounds were also examined by the application on the backs of mice. The radioactivities in most tissues reached to the maximal levels at 12 h or 18 h after dosing, which corresponded to 11–76% of the maximal levels given by the oral administration (Kanetoshi et al. 1988a). These results show the high percutaneous absorbability of Irgasan DP300 and its chlorinated derivatives.The intraperitoneal administrations of III and IV to rats induced hepatic microsomal aminopyrine N-demethylase and aniline 4-hydroxylase activities similarly to phenobarbital. These chlorinated derivatives also increased cytochrome P-450 content, and the activities of aminopyrine N-demethylase and N-methylaniline N-demethylase in hepatic microsomes from mice. The extents of the increases were similar to those by phenobarbital and 3-methylcholanthrene. 相似文献