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1.
Ichiro Yasuda Takuji Iwashita Takaya Ohnishi Tsuyoshi Mukai Masamichi Enya Eiichi Tomita Hisataka Moriwaki 《Digestive endoscopy》2006,18(Z1):S92-S95
Endoscopic nasobiliary drainage (ENBD) is a well established mode of biliary decompression. Although ENBD is certainly an uncomfortable procedure with the potential risk of spontaneous dislocation or removal of the drainage catheter by disoriented patients, it has several advantages over endoscopic biliary drainage (EBD) using an indwelling stent. The current indications for ENBD are: (i) temporary drainage to treat obstructive jaundice and cholangitis caused by malignant or benign biliary stricture; (ii) urgent drainage to treat suppurative cholangitis primarily caused by common bile duct stones; (iii) temporary drainage after stone removal in patients with suspected incomplete clearance and/or with cholangitis; and (iv) biliary leaks that occur primarily after surgery, as well as other indications. Different types of nasobiliary catheters are currently available that have been designed with various diameters, shapes, and materials. However, the current catheters are not considered by most endoscopists to be sufficient. Further improvements are needed to achieve better drainage and better maneuverability. 相似文献
2.
Shiro Akinaga Tadashi Ashizawa Katsushige Gomi Hiroe Ohno Makoto Morimoto Chikara Murakata Masami Okabe 《Cancer chemotherapy and pharmacology》1992,29(4):266-272
Summary Novel derivatives of K-252a, (8R*,9S*,11S*)-(–)-9-hydroxy-9-methoxycarbonyl-8-methyl-2,3,9,10-tetrahydro-8, 11-epoxy-1H,8H,11H-2,7b,11a-triazadibenzo [a,g]-cycloocta[cde]trinden-1-one, an inhibitor of protein kinases and calmodulin-dependent phosphodiesterase, were synthesized and evaluated for their antitumor activity in vitro and in vivo. Of ten derivatives tested, four were active against the P388 murine leukemia i. p.-i. p. system, although K-252a was inactive. Among these derivatives, KT6124 was selected for further biological evaluation studies because its efficacy was the highest. KT6124 was also active against sarcoma 180 and B16 melanoma. It exerted a relatively broad spectrum of antiproliferative activity against 20 human tumor cell lines in vitro. To determine the mechanism(s) of action underlying the antitumor activity of KT6124, we tested the drug for inhibition of protein kinases, including Ca2+-and phospholipid-dependent protein kinase (PKC), in intact A431 human epidermoid carcinoma cells in comparison with the PKC-inhibitory activity of K-252a. KT6124 did not antagonize the action of phorbol 12-myristate 13-acetate (PMA) in A431 cells, whereas K-252a did, suggesting that KT6124 may not act on protein kinases in the cells. The interaction of KT6124 with DNA in living cells was examined by the alkaline elution method. KT6124 apparantly exhibited DNA scission both dose-and time-dependently in the target cells. The DNA breakage was dependent on proteinase K treatment, suggesting its possible interaction with DNA-related enzyme(s). These results indicate that KT6124 exerts antitumor activity by acting on DNA or on DNA-related enzyme(s) in tumor cells rather than via the inhibition of protein kinases. 相似文献
3.
Effects of a newly introduced polyoxyethylene-modified superoxide dismutase (SOD-POE) on reperfusion induced arrhythmias were examined in the pentobarbital anesthetized rat. Reperfusion induced arrhythmias were elicited by occlusion of the left anterior descending coronary artery (LAD) for 15 min and subsequent release. The LAD occlusion was performed by compressing the artery using a suction cup of 2 mm in diameter placed on the LAD to which negative pressure was applied. The LAD occlusion and release was repeated at an interval of 30 min. SOD-POE or human SOD (h-SOD) (1000 U/kg) was injected intravenously 15 min prior to the occlusion at the second trial of the occlusion. In the control group, various types of arrhythmias including ventricular fibrillation (Vf), ventricular tachycardia (VT), premature ventricular contraction (PVC) and premature atrial contraction (PAC) were elicited immediately after release of the occlusion. In the SOD-POE-treated group, Vf and VT were completely prevented and the numbers of PVC and PAC significantly decreased, while pretreatment with h-SOD did not prevent the occurrence of reperfusion induced arrhythmias. The protective effects of SOD-POE lasted for more than 90-120 min. The plasma half life for SOD-POE was 10.8 hr, while that for h-SOD was 8.6 min. Results indicate that intravenous administration of SOD-POE would provide a new means of preventing reperfusion induced arrhythmias occurring in clinical situations. 相似文献
4.
5.
Hiroko Ida-Yonemochi Wael Swelam Chikara Saito Takashi Saku 《Journal of oral pathology & medicine》2005,34(1):59-61
A case of angiolipoma occurring in the buccal mucosa of a 69-year-old male is described. The patient had noticed a painless mass in his buccal mucosa for 2 years. The surgically removed tumor, measuring 9 mm in diameter, was mainly located in the submucosal layer with focal expansion into the muscle layer. Histologically, the tumor was well-demarcated and composed of proliferations of mature fat cells and fibrous connective tissue containing many small blood vessels, which were evenly distributed. There was diffuse infiltration of a large number of mast cells, which were immunopositive for vascular endothelial growth factor (VEGF) especially around blood vessels, suggesting that VEGF produced by mast cells in angiolipomas plays an important role in the vascular proliferation in this particular tumor. 相似文献
6.
Toshiya Inada M.D. Fumiko Minagawa B.A. Satoru Iwashita M.D. Tatsuji Tokui M.D. 《Psychiatry and clinical neurosciences》1994,48(4):729-735
Abstract: In order to examine the characteristics of potential difficult-to-manage psychiatric cases, seven potential subgroups were extracted from the criminal offenders who were sent to the division of psychiatric diagnosis, Tokyo District Public Prosecutors Office for Pre-Prosecution Psychiatric Justice (PPPJ). The following criteria were used to select the potential subgroups: offenders who had experienced compulsory discharge from a mental hospital, those who had experienced Involuntary Admission to the mental hospital by the Prefectural Governor at least twice, those who had experienced admission to mental hospitals on more than 5 occasions, those who had been put on PPPJ previously for other criminal matters at least 3 times, those who had previously attempted suicide, and those who had committed homicide or arson. From the results of this study, it could be concluded that at least two types of "difficult-to-manage" psychiatric cases exist in the criminal offenders. 相似文献
7.
Matsukawa T.; Hanagata K.; Ozaki M.; Iwashita H.; Koshimizu M.; Kumazawa T. 《British journal of anaesthesia》1997,78(4):396-399
We tested the hypothesis that premedication with i.m. midazolam decreases
core temperature dose-dependently. We studied six male volunteers, in
random order, on 3 days: (1) no midazolam administration (control day), (2)
midazolam 0.025 mg kg-1 i.m., (3) midazolam 0.075 mg kg-1 i.m. On the first
day, subjects were maintained alert during a 30- min control period. On the
second and third days, midazolam 0.025 or 0.075 mg kg-1 was administered
i.m. Core temperatures were measured at the right tympanic membrane. Four
adhesive skin surface probes were fixed on the chest, upper right arm,
lateral calf and thigh. Finger tip perfusion was evaluated using forearm
minus fingertip and calf minus toe, skin surface temperature gradients.
Thirty minutes after midazolam i.m., the level of sedation in the
volunteers was assessed. Peripheral venous blood was obtained immediately
after the assessment of the level of sedation. Tympanic membrane
temperatures after administration of midazolam 0.075 mg kg-1 i.m. were
significantly lower than those on the control and midazolam 0.025 mg kg-1
i.m. days at 20 and 30 min. The decreases in tympanic membrane temperatures
at 30 min after midazolam i.m. became larger as the volunteers were more
deeply sedated. i.m. midazolam produced a concentration-dependent decrease
in tympanic membrane temperature at 30 min after midazolam 0.025 and 0.075
mg kg-1 i.m. We conclude that midazolam impaired tonic thermoregulatory
vasoconstriction, allowing core-to-peripheral heat redistribution in a
dose-dependent manner after i.m. administration.
相似文献
8.
Yoshitomo Kashiwagi Chikara Kikuchi Jun-ichi Anzai 《Journal of electroanalytical chemistry (Lausanne, Switzerland)》2002,518(1):51-55
Electrocatalytic dehalogenation of organohalides was studied using a nickel(II) tetraazamacrocyclic complex-modified graphite felt electrode. The nickel(II) tetraazamacrocyclic complex-modified graphite felt electrode was prepared by attaching nickel(II) (6-(2′-hydroxyethyl)-1,4,8,11-tetraazacyclotetradecane)perchlorate chemically to the carboxyl groups of a thin poly(acrylic acid) layer coated on the graphite felt. The modified electrode gave a reversible electron transfer for the nickel(II)/nickel(I) redox couple in cyclic voltammetry at ?0.95 V versus Ag/AgCl. A preparative electrocatalytic dehalogenation of organohalides was successfully achieved on the modified electrode with an adequate current efficiency (55.6–94.8%), conversion (34.2–100%) and turnover number of the Ni catalyst (667–3333). 相似文献
9.
Tomomi Iwashita Kazuo Kitazawa Jun-Ichi Koyama Hisashi Nagashima Toru Koyama Yuichiro Tanaka Kazuhiro Hongo Hiroshi Okudera Kazufumi Okamoto 《Journal of clinical neuroscience》2007,14(1):68-71
A patient with cerebral deep sinus thrombosis, which was not diagnosed on the first examination, is reported. A 46-year-old woman presented with headache and vomiting. Neurological examination and a brain computed tomography (CT) scan showed no obvious abnormal findings. The patient suffered disturbed consciousness on the day after the examination, and was admitted to our emergency centre. A CT scan and magnetic resonance imaging revealed an ischaemic lesion in the left basal ganglia, suggesting deep sinus occlusion. Anticoagulant therapy was administered. One day after admission, a CT scan showed a haematoma and severe brain swelling in the same region. Cerebral angiography demonstrated a straight sinus occlusion. Intracranial pressure was not controlled with hypothermia, and the patient died 25 days after admission. Review of the initial CT scan revealed subtle, early findings of deep venous thrombosis that were missed on first examination. 相似文献
10.
The complete nucleotide sequence of rice tungro spherical virus (RTSV) strain Vt6, originally from Mindanao, the Philippines, with higher virulence to resistant rice cultivars, was determined and compared with the published sequence for the Philippine-type strain A (RTSV-A-Shen). It was reported that RTSV-A was not able to infect a rice resistant cultivar TKM 6 (10). RTSV-Vt6 and RTSV-A-Shen share 90% and 95% homology at nucleotide and amino-acid levels, respectively. The N-terminal leader sequence of RTSV-Vt6 contained a 39-amino acids-region (positions 65 to 103) which was totally different from that of RTSV-A-Shen; the difference resulted from frame shifting by nucleotide insertions and deletions. To confirm the amino-acid sequence differences of the leader polypeptide, the same region was cloned and sequenced using a newly obtained variant of RTSV-type 6, which had been collected in the field of IRRI, and seven field isolates from Mindanao, the Philippines. Since all the sequences of the target region are identical to that of the Vt6 leader polypeptide, the sequence difference in the leader region seems not to correlate with the virulence of Vt6. 相似文献