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排序方式: 共有1230条查询结果,搜索用时 15 毫秒
71.
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
72.
This paper proposes a novel learning method for a mixture of recurrent neural network (RNN) experts model, which can acquire the ability to generate desired sequences by dynamically switching between experts. Our method is based on maximum likelihood estimation, using a gradient descent algorithm. This approach is similar to that used in conventional methods; however, we modify the likelihood function by adding a mechanism to alter the variance for each expert. The proposed method is demonstrated to successfully learn Markov chain switching among a set of 9 Lissajous curves, for which the conventional method fails. The learning performance, analyzed in terms of the generalization capability, of the proposed method is also shown to be superior to that of the conventional method. With the addition of a gating network, the proposed method is successfully applied to the learning of sensory–motor flows for a small humanoid robot as a realistic problem of time series prediction and generation. 相似文献
73.
Development and validation of the Humanitarian Aid Difficulty Scale for Japanese healthcare workers 下载免费PDF全文
Norihito Noguchi RN PHN MSN Satoshi Inoue MD PhD FACS Chisato Shimanoe PH PhD Koichi Shinchi MD PhD 《Nursing & health sciences》2016,18(4):442-449
Few studies have investigated deployment‐related experiences of healthcare workers dispatched for medical humanitarian aid or attempted to assess their difficult living and working environments. This is the first study to develop and validate a scale to measure these kinds of difficulties, in 264 Japanese healthcare workers. The Humanitarian Aid Difficulty Scale was developed in three stages. First, an item pool was generated based on literature and expert reviews. The scale was then tested in a pilot study. Reliability and validity were identified through exploratory and confirmatory factor analysis and Cronbach's alpha. The scale consisted of 23 items across five factors based on exploratory factor analysis (cooperation, health status, infrastructure, culture and customs, and supplies and equipment). The total variance explained was 60.7%. Reliability of the five factors was acceptable and validity was supported by confirmatory factor analysis. Cronbach's alpha for the scale was 0.87. The scale may enable evaluation of the level of difficulty of the living and working environments of Japanese healthcare workers in medical humanitarian aid who are at a greater risk of distress. 相似文献
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Kazushige Nishimura Chisato Fujiyama Keiji Nakashima Yuji Satoh Yuji Tokuda Jiro Uozumi 《International urology and nephrology》2009,41(4):869-875
Objective
We evaluated the correlation of radiological findings obtained by MRI study with pathological diagnosis in invasive bladder cancer treated with neoadjuvant chemotherapy, with or without radiation.Design, Setting, and Participants
Twenty-seven patients, who underwent total or partial cystectomy for invasive bladder tumors, were enrolled into the present study. Eight cases had received neoadjuvant chemotherapy following the staging biopsy (group A), ten cases had received chemo-radiation therapy following the staging biopsy (group B), and nine cases had received preoperative staging biopsy alone (group C). As a final treatment, 12 of the 27 patients underwent total cystectomy and the other 15 patients underwent partial cystectomy. MRI was conducted prior to total or partial cystectomy in each case. The pathological stage was assessed by histological examination of the entire layer of the bladder wall.Results and Limitations
Tumor stage assessed by MRI was consistent with pathological findings in 16 of the 27 cases (59.3%), while MRI produced over-staging in 7 cases and under-staging in 4 cases. The accuracy of staging was 75.0, 30.0, and 77.8% in groups A, B, and C, respectively. The accuracy of MRI staging in group B was lower than that in group C (P < 0.05). There was no difference in the accuracy of MRI staging between groups A and C.Conclusion
MRI is useful for the staging of bladder cancer. However, care needs to be taken when staging invasive bladder tumors treated with neoadjuvant chemo-radiation therapy, because inflammatory infiltrations and/or fibrous changes caused by the chemotherapy or chemo-radiation therapy make precise staging with MRI difficult. 相似文献76.
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78.
Teraoka H Kubota A Dong W Kawai Y Yamazaki K Mori C Harada Y Peterson RE Hiraga T 《Toxicology and applied pharmacology》2009,234(1):33-33
Previously, we reported that 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) evoked developmental toxicity required activation of aryl hydrocarbon receptor type 2 (AHR2), using zebrafish embryos. However, the downstream molecular targets of AHR2 activation are largely unknown and are the focus of the present investigation. TCDD induces cyclooxygenase 2 (COX2), a rate-limiting enzyme for prostaglandin synthesis in certain cells. In the present study, we investigated the role of the COX2-thromboxane pathway in causing a specific endpoint of TCDD developmental toxicity in the zebrafish embryo, namely, a decrease in regional blood flow in the dorsal midbrain. It was found that the TCDD-induced reduction in mesencephalic vein blood flow was markedly inhibited by selective COX2 inhibitors, NS-398 and SC-236, and by a general COX inhibitor, indomethacin, but not by a selective COX1 inhibitor, SC-560. Gene knock-down of COX2 by two different types of morpholino antisense oligonucleotides, but not by their negative homologs, also protected the zebrafish embryos from mesencephalic vein circulation failure caused by TCDD. This inhibitory effect of TCDD on regional blood flow in the dorsal midbrain was also blocked by selective antagonists of the thromboxane receptor (TP). Treatment of control zebrafish embryos with a TP agonist also caused a reduction in mesencephalic vein blood flow and it too was blocked by a TP antagonist, without any effect on trunk circulation. Finally, gene knock-down of thromboxane A synthase 1 (TBXS) with morpholinos but not by the morpholinos' negative homologs provided significant protection against TCDD-induced mesencephalic circulation failure. Taken together, these results point to a role of the prostanoid synthesis pathway via COX2-TBXS-TP in the local circulation failure induced by TCDD in the dorsal midbrain of the zebrafish embryo. 相似文献
79.
Takafumi Hara Akira Hirasawa Qi Sun Keiko Sadakane Chisato Itsubo Tomoyo Iga Tetsuya Adachi Taka-aki Koshimizu Toshihiro Hashimoto Yoshinori Asakawa Gozoh Tsujimoto 《Naunyn-Schmiedeberg's archives of pharmacology》2009,380(3):247-255
GPR120 and GPR40 are G-protein-coupled receptors whose endogenous ligands are medium- and long-chain free fatty acids, and
they are thought to play an important physiological role in insulin release. Despite recent progress in understanding their
roles, much still remains unclear about their pharmacology, and few specific ligands for GPR120 and GPR40 besides medium-
to long-chain fatty acids have been reported so far. To identify new selective ligands for these receptors, more than 80 natural
compounds were screened, together with a reference compound MEDICA16, which is known to activate GPR40, by monitoring the
extracellular regulated kinase (ERK) and [Ca2+]i responses in inducible and stable expression cell lines for GPR40 and GPR120, respectively. MEDICA16 selectively activated
[Ca2+]i response in GPR40-expressing cells but not in GPR120-expressing cells. Among the natural compounds tested, grifolin derivatives,
grifolic acid and grifolic acid methyl ether, promoted ERK and [Ca2+]i responses in GPR120-expressing cells, but not in GPR40-expressing cells, and inhibited the α-linolenic acid (LA)-induced
ERK and [Ca2+]i responses in GPR120-expressing cells. Interestingly, in accordance with the pharmacological profiles of these compounds,
similar profiles of glucagon-like peptide-1 secretion were seen for mouse enteroendocrine cell line, STC-1 cells, which express
GPR120 endogenously. Taken together, these studies identified a selective GPR40 agonist and several GPR120 partial agonists.
These compounds would be useful probes to further investigate the physiological and pharmacological functions of GPR40 and
GPR120. 相似文献
80.