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991.
Teruaki Tagawa Koichi Kono Tomotaro Dote Kan Usuda Hiroyuki Nishiura Chisato Koizumi Masahisa Saito Hisangea Nakaya Hidehiro Nagaie 《International archives of occupational and environmental health》2000,73(9):S98-S100
Boron (B) compounds have been widely used in the chemical industry, agriculture, and environmental science. The kinetics and toxicity of B were studied by analyzing several serum and urine parameters after a single intravenous injection of sodium tetraborate solution (B: 85.7 mg/kg) in Wistar male rats. Blood samples were removed at 0, 1, 2, 4, and 6 h after injection. The serum parameters studied included: B, Na, Ca, K, P, Mg, %-GTP, AST, ALT, BUN, Cr, CK, LDH and ALD. Plasma concentration-time profiles of B were evaluated by a nonlinear least-squares method for fitting data to polyexponential equations and calculation of relevant pharmacokinetic parameters. Urine samples were collected from the bladder following infusion. The urinary parameters that were studied included urine volume and excretion of B, Cr and NAG. Results indicated that a two-compartment model could describe the elimination of B from plasma after intravenous administration. Urine volume significantly increased. A diuretic effect of B was noted. 相似文献
992.
993.
In vivo and in vitro characterization of a novel neuroprotective strategy for stroke: ischemic postconditioning. 总被引:2,自引:0,他引:2
Giuseppe Pignataro Robert Meller Koichi Inoue Andrea N Ordonez Michelle D Ashley Zhigang Xiong Rosaria Gala Roger P Simon 《Journal of cerebral blood flow and metabolism》2008,28(2):232-241
As clinical trials of pharmacological neuroprotective strategies in stroke have been disappointing, attention has turned to the brain's own endogenous strategies for neuroprotection. Recently, a hypothesis has been offered that modified reperfusion subsequent to a prolonged ischemic episode may also confer ischemic neuroprotection, a phenomenon termed 'postconditioning'. Here we characterize both in vivo and in vitro models of postconditioning in the brain and offer data suggesting a biological mechanism for protection. Postconditioning treatment reduced infarct volume by up to 50% in vivo and by approximately 30% in vitro. A duration of 10 mins of postconditioning ischemia after 10 mins of reperfusion produced the most effective postconditioning condition both in vivo and in vitro. The degree of neuroprotection after postconditioning was equivalent to that observed in models of ischemic preconditioning. However, subjecting the brain to both preconditioning as well as postconditioning did not cause greater protection than each treatment alone. The prosurvival protein kinases extracellular signal-regulated kinase (ERK), p38 mitogen-activated protein kinase (MAPK), and Akt show prolonged phosphorylation in the cortex of postconditioned rats. Neuroprotection after postconditioning was inhibited only in the presence of LY294002, which blocks Akt activation, but not U0126 or SB203580, which block ERK and P38 MAP kinase activity. In contrast, preconditioning-induced protection was blocked by LY294002, U0126, and SB203580. Our data suggest that postconditioning may represent a novel neuroprotective approach for focal ischemia/reperfusion, and one that is mediated, at least in part, by the activation of the protein kinase Akt. 相似文献
994.
Hitoshi Iyatomi Hiroshi Oka M Emre Celebi Masahiro Hashimoto Masafumi Hagiwara Masaru Tanaka Koichi Ogawa 《Computerized medical imaging and graphics》2008,32(7):566-579
In this paper, we present an Internet-based melanoma screening system. Our web server is accessible from all over the world and performs the following procedures when a remote user uploads a dermoscopy image: separates the tumor area from the surrounding skin using highly accurate dermatologist-like tumor area extraction algorithm, calculates a total of 428 features for the characterization of the tumor, classifies the tumor as melanoma or nevus using a neural network classifier, and presents the diagnosis. Our system achieves a sensitivity of 85.9% and a specificity of 86.0% on a set of 1258 dermoscopy images using cross-validation. 相似文献
995.
996.
Rat‐bite fever identified by polymerase chain reaction detection of Streptobacillus moniliformis DNA
Daiki NAKAGOMI Nobuhiro DEGUCHI Akiko YAGASAKI Kazutoshi HARADA Naotaka SHIBAGAKI Masanobu KIMURA Koichi IMAOKA Shinji SHIMADA 《The Journal of dermatology》2008,35(10):667-670
A 74‐year‐old woman presented with erythema of the extremities, a high fever and arthralgia after being bitten by a rat. The patient was diagnosed as having rat‐bite fever based on the symptoms and clinical course, as well as the polymerase chain reaction detection of Streptobacillus moniliformis DNA in the crust of the bite site. This is the first case to be diagnosed using polymerase chain reaction on a crusted skin lesion specimen. Although clinical symptoms initially remitted with minocycline therapy, they relapsed. Subsequent administration of piperacillin sodium resulted in complete disappearance of the high fever and arthralgia. 相似文献
997.
Takao UCHIDA Koichi MAKIMURA Katsuhito ISHIHARA Hideaki GOTO Yoshito TAJIRI Mariko OKUMA Ryuichi FUJISAKI Katsuhisa UCHIDA Sigeru ABE Masafumi IIJIMA 《The Journal of dermatology》2009,36(4):202-208
The positive rates of dermatophytes isolated and identified by conventional methods are rather low. Moreover, clinical isolates sometimes show atypical morphology, and in such cases microscopic methods are not applicable for identification. The present study was performed to assess the utility of specific polymerase chain reaction (PCR)-based methods for Trichophyton rubrum and Trichophyton mentagrophytes as diagnostic tools for dermatophytoses. Both conventional morphological identification and specific PCR methods based on the nuclear ribosomal internal transcribed spacer (ITS)1 DNA sequence were performed to identify dermatophyte species from clinical specimens of patients who visited Kawasaki Social Insurance Hospital between 16 May and 17 August 2005. Specific PCR methods were also directly applied to clinical specimens, and the results of the two methods were compared. The clinical samples examined consisted of 126 skin scale specimens and 80 nail specimens. The positive rates of culture isolation from clinical specimens were 67% and 33% for skin scale and nail specimens, respectively. In contrast, PCR analysis yielded a positive rate of 100% for clinical isolates from both skin scales and nails, and rates of 95% and 99% were obtained by direct application to clinical specimens. The results of the present study indicated that specific PCR is highly advantageous as a diagnostic tool for detection and identification of dermatophytes on direct application to skin scale or nail specimens. 相似文献
998.
Koichi Matsumoto MD Shigeru Moriyama Yasushi Iwata Tohru Masuda Kazuo Matsumoto Keiji Iriyama 《Surgery today》1986,16(6):456-459
Histopathological examination, specific mucin staining and analysis of cellular DNA content of rectal mucosa were carried
out in twenty-eight tissue specimens biopsied from ten adult and eight adolescent patients with ulcerative colitis. There
was an increase in proliferative activity in the rectal mucosa in both groups with active colitis, but, there were no significant
differences in the potential for malignant transformation of rectal mucosa in these groups. 相似文献
999.
1000.