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51.
Ruri Aoki Tetsuya Arinobu Takeshi Kumazawa Hideki Hattori Hiroshi Noguchi 《Forensic Toxicology》2007,25(1):8-15
An automated on-line method for simultaneous analysis of five phenothiazine drugs by high-performance liquid chromatography
(HPLC)/sonic spray ionization mass spectrometry (SSI-MS) has been established, using backflush column switching. A 400-μl
portion of serum sample diluted 81-fold with distilled water was subjected to the on-line system. In the system, an Oasis
HLB cartridge was used as the precolumn for extraction; large molecules such as proteins in serum were discarded by use of
distilled water containing 0.1% formic acid as a mobile phase. After switching a valve, the analytes trapped in the precolumn
were eluted in the backflush mode and separated by a Chromolith Performance RP-18e column, which is composed of C18-bonded monolithic silica. The column effluents were then introduced into the SSI-MS. The present method provided successful
separation and determination of six phenothiazines including an internal standard. Satisfactory linearities, reproducibility,
and sensitivity were obtained at concentration levels that matched the toxic levels of phenothiazines. All drug peaks appeared
within 18 min, and the system could be reequilibrated in only about 8 min for the next run. Because of the simplicity and
rapidness of the method, it is likely to be useful in the fields of emergency medicine and forensic toxicology. 相似文献
52.
Manabu Muto Mitsuhiro Fujishiro Yoshitaka Sato Yasumasa Niwa Mitsuru Kaise Mototsugu Kato Kaiyo Takubo 《Digestive endoscopy》2007,19(Z1):S153-S155
Optical technological innovations enable us to visualize cellular nuclei endoscopically. Herein is described a protocol design for a multicenter study for the ex vivo evaluation of endocytoscopy. The present study was performed by the Endoscopy Forum Japan study group. 相似文献
53.
Atsushi Takai Yoshihiro Okabe Nobuhiro Aoki Mariko Takada Shuji Yamamoto Naoya Kimoto Mikio Fujita Akihiko Okada Chiharu Kawanami Yukinobu Takimoto Akio Orino 《Nihon Shokakibyo Gakkai zasshi》2007,104(10):1498-1503
A 77-year-old man, who underwent segmental pancreatectomy for intraductal papillary mucinous adenoma in 2001, was referred to our hospital with complaints of hematemesis and melena on January, 2004. Emergency upper gastrointestinal endoscopy showed a pulsating submucosal protrusion in the duodenal bulb, which was identified as a gastroduodenal arterial aneurysm measuring 1.5cm on abdominal CT imaging. Transcatheter arterial embolization of the aneurysm with metallic coils was successfully performed. Periodically repeated endoscopic examination has revealed the coils protruding into the duodenal lumen without any serious complication. 相似文献
54.
H. Hattori E. Nagata Y. Oya T. Takahashi M. Aoki D. Ito N. Suzuki 《European journal of neurology》2007,14(11):1288-1291
Miyoshi myopathy (MM) is an autosomal recessive distal muscular dystrophy characterized by mutations of the dysferlin gene. Although several pairs of homozygous/heterozygous mutations have been reported, few effective treatments of MM are available. We had observed the decreased serum creatine kinase (CK) before and after administration of dantrolene in the elder brother and the increased serum CK before and after discontinuance of the drug on suspicion of drug-induced hepatopathy in the younger sister. We report a novel pair of heterozygous mutations in the 3'-splicing site of exon 26 and the translation site of exon 28 of the dysferlin gene in two siblings, and effective treatment of their MM with dantrolene. 相似文献
55.
Kenji Yamao Atsushi Irisawa Hiroyuki Inoue Koji Matsuda Mitsuhiro Kida Shomei Ryozawa Yoshiki Hirooka Teruo Kozu 《Digestive endoscopy》2007,19(Z1):S180-S205
Standard imaging techniques using a curved linear array echoendocope are summarized to facilitate the attainment of expertise in endoscopic ultrasonography and endoscopic ultrasound‐guided fine needle aspiration, and to promote the widespread use of this diagnostic and therapeutic tool. Typical images of the mediastinal organs, the bilio‐pancreatic systems and neighboring organs by scanning from the esophagus, stomach, duodenal bulb, and descending portion of the duodenum, are shown in a sequential manner. The basic techniques of endoscopic ultrasound‐guided fine needle aspiration are also presented. 相似文献
56.
Antimetastatic Activity of Polymeric RGDT Peptides Conjugated with Poly(ethylene glycol) 总被引:1,自引:0,他引:1
Ikuo Saiki Junya Yoneda Yu Igarashi Miho Aoki Naoto Kusunose Kei-ichi Ono Ichiro Azuma 《Cancer science》1993,84(5):558-565
Polymeric peptides containing defined repetitive or cyclic structures of RGDT sequence, (RGDT)n (n = 1 to 11) and cyclo(RGDT)n (n=2 to 4), at a dose of 500 μg exhibited an inhibitory effect on experimental lung metastasis upon co-injection with tumor cells and the magnitude of the effect increased in parallel with the increase of degree of repetition of the RGDT sequence. The conjugation of (RGDT)n (n = 1, 5, 11) with poly(ethylene glycol), PEG as a polymeric carrier led to enhanced inhibition of lung metastasis in proportion to the degree of RGDT sequence repetition and in a dose-dependent manner. Multiple i.v. administrations of PEG-(RGDT)11, at 2-day and 3-day intervals before the excision of primary tumors, effectively inhibited spontaneous lung metastasis by s.c. inoculation of tumors, whereas (RGDT)11 exhibited inhibition of lung metastasis only when given at 2-day intervals. This indicates that the conjugation of PEG with (RGDT)n allowed the prolongation of administration interval, implying a sustained inhibitory effect on tumor metastasis. In support of this supposition, a decrease in the arrest of radiolabeled tumor cells in the lungs was observed when PEG-(RGDT)11 was co-injected i.v. with tumor cells, or injected i.v. one day before tumor inoculation. In contrast, (RGDT)11 significantly inhibited the tumor cell arrest in the lungs only upon co-injection with tumor cells. We also noted that (RGDT)n, cyclo(RGDT)n and PEG-(RGDT)11 inhibited tumor cell invasion into Matrigel in a concentration-dependent manner and in proportion to the degree of RGDT sequence repetition, indicating that the peptide-mediated antimetastatic effect is partly associated with the anti-invasive potential. Thus, the conjugation of anti-cell adhesive and antimetastatic RGDT peptide with PEG might provide a therapeutically promising basis for the prevention of cancer metastasis (“anti adhesion therapy”). 相似文献
57.
Chromosomal Mapping of Genetic Locus Associated with Thymus-size Enlargement in BUF/Mna Rats 总被引:2,自引:1,他引:1
Yoshiki Murakumo Masahide Takahashi Atsushi Arakawa Mitsuhiro Saito Hiroyuki Amo Hideki Katoh Mutsushi Matsuyama 《Cancer science》1993,84(8):838-840
The thymoma-prone rat of the BUF/Mna strain is a useful model for human thymoma. In this strain thymoma development is regulated by a single autosomal susceptible gene, Tsr-1. At pre-thymoma age, BUF/Mna rats have extremely large thyrauses, when compared to those of other strains of rats. Genetic studies in crosses between BUF/Mna rats with large thymuses and WKY/NCrj rats with small thymuses suggested the presence of a major autosomal gene, Ten-1 , which contributes to thymus enlargement in a backcross population. Linkage studies between Ten-1 and microsatellite markers in backcross rats of (WKY/NCrj×BUF/Mna)Fl×BUF/Mna have led to the localization of Ten-1 in chromosome 1. This result may provide an approach to clone Tsr-1 , which could be allelic to Ten-1. 相似文献
58.
Tomoyuki Kawada M.D. Yasuo Kiryu M.D. Shigenobu Aoki Ph.D. Shosuke Suzuki M.D. 《Psychiatry and clinical neurosciences》1992,46(4):937-940
Abstract: The possibility on placing electrodes at Fpz-A2 instead of C3 -A2 was investigated to obtain a more stable configuration avoiding obstruction by the hair. Our original system of alpha wave detection by a microcomputer was used, and a total of 22 all-night hypnograms of five healthy young students waa recorded. Pearson's moment correlation coefficients of alpha wave % between the two positions were 0.780–0.948. Except for one subject, alpha wave % taken at Fpz-A2 tended to be 3–5% lower than that at C3 -A2 . The above analysis indicates that using EEG electrode position of Fpz-A2 is valid and useful as a stable electrode configuration for a long-time monitoring. 相似文献
59.
Mitsuhiro Denda Barbara E. Brown Peter M. Elias K. R. Feingold 《Archives of dermatological research》1997,289(2):104-110
Isoprenylation is the covalent attachment of isoprenyl groups, intermediates of the cholesterol biosynthesis pathway, to carboxy
terminal cysteine residues of proteins. Numerous proteins are isoprenylated including small GTP binding proteins, trimeric
G proteins, and nuclear lamins, and these prenylated proteins regulate a variety of cell functions, including cell growth,
cytokinesis, and differentiation. Here, we quantitated protein prenylation and determined which proteins are prenylated in
the epidermis of hairless mice by radiolabeling with
3
H-mevalonolactone following acute or chronic epidermal injury. In normal epidermis, four major radiolabeled bands, with molecular
weights of 17–26, 48, 54, and 68 kDa, were observed. The levels of each of these bands increased by 24–63% 16 h following
acute epidermal injury induced by topical acetone treatment or tape stripping, returning to normal by 24 h. On 2D gel electrophoresis,
there were no major differences between the patterns of labeling following barrier disruption. Subacute epidermal injury induced
by either acetone or tape stripping twice a day for 7 days and chronic injury induced by feeding an essential fatty acid-deficient
(EFAD) diet, also resulted in a significant increase in protein prenylation. As with acute injury, SDS-PAGE and 2D gel electrophoresis
did not reveal marked differences in the pattern of protein prenylation. These results demonstrate that the prenylation of
proteins in the epidermis is stimulated by injury, suggesting that one or more of these prenylated species may be important
in epidermal proliferation or differentiation.
Received: 29 May 1996 相似文献
60.
Yasuo Aoki Souji Maruo Akira Arakawa Sadao Sasaki Seiki Hori 《Journal of orthopaedic science》1997,2(6):434-441
Changes in the nerve fibers of the spinal cord were studied in rat experimental epidural tumor models. Light microscopy showed
demyelinization in all with rats paraparesis and paraplegia. Cross-sectional views of nerve fibers stained with 3,3dipentyloxacarbo-cyanine
iodide, obtained by confocal laser scanning microscopy, showed distorted, shrunken fibers with a low fluorescence intensity.
Changes in the electrolyte contents of nerve fibers were studied by electron probe X-ray microanalysis. The K concentration
in axons and the myelin sheath was increased in the paraparesis group, but was decreased in the paraplegia group. These findings
suggest that, in the paraparesis group, compression of the spinal cord damaged cell membrane channels, which subsequently
caused an increase in intracellular K, a decline in the action potential, and low-intensity fluorescence of nerve fibers.
On the other hand, in the paraplegia group, destruction of cell membranes caused a decrease in intracellular K until it approached
the extracellular level. This reduced both the action potential and the fluorescence intensity. As Ca and Mg concentrations
in both axons and the myelin sheath increased in relation to the severity of neurologic damage, it appears that these electrolytes
may also play an important role in damage to nerve fibers. 相似文献