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During hemodialysis, amino acid loss through the dialysate remained a significant problem and was not clear in some dialyzers; therefore, we investigated amino acid loss with hydrophilic and nonhydrophilic polyester–polymer alloy membranes and polyacrylonitrile membranes. Nine maintenance hemodialysis patients were studied to assess amino acid loss during hemodialysis with the three membranes. Total amino acid losses were 85.7 ± 27.2 mg/L, 83.3 ± 16.1 mg/L, and 72.1 ± 22.5 mg/L with the hydrophilic, nonhydrophilic polyester–polymer alloy, and polyacrylonitrile membranes, respectively. Amino acid losses were greater with the hydrophilic membrane compared with the polyacrylonitrile membrane for ornithine (2.0 ± 0.6 vs. 1.4 ± 0.4 mg/L, P = 0.025), phenylalanine (2.4 ± 0.9 vs. 1.8 ± 0.8 mg/L, P = 0.012), and tryptophan (0.6 ± 0.2 vs. 0.4 ± 0.2 mg/L, P = 0.023). Amino acid losses were greater with the nonhydrophilic membrane than with the polyacrylonitrile membrane for ornithine (2.0 ± 0.4 vs. 1.4 ± 0.4 mg/L, P = 0.017), phenylalanine (2.3 ± 0.5 vs. 1.8 ± 0.8 mg/L, P = 0.018), tryptophan (0.7 ± 0.2 vs. 0.4 ± 0.2 mg/L, P = 0.003), and cystine (3.2 ± 0.7 vs. 2.0 ± 0.7 mg/L, P = 0.005). In conclusion, greater losses of ornithine, phenylalanine, tryptophan, and cystine were observed with polyester–polymer alloy than with polyacrylonitrile membranes during hemodialysis. Constant attention should be paid to the amino acid loss profile to improve nutritional control in hemodialysis patients.  相似文献   
94.
The honeybee product propolis and its extracts are known to have biological effects such as antibiotic, anti-viral, anti-inflammatory and anti-tumor activities. This study was designed to investigate whether water-soluble propolis (WSP) inhibits tumor growth. The tumor cell line used was mouse sarcoma 180 (S-180), and its growth was determined in vitro and in vivo with exposure to different concentrations of WSP. The effects of WSP on tumor cells in vitro were evaluated by measuring the intracellular uptake of 3H-thymidine. 3H-thymidine uptake was inhibited in accordance with the concentration of WSP. The minimum concentration of WSP necessary for 3H-thymidine uptake inhibition was 1.0 microg/ml and uptake was suppressed to 88% of the level in non-treated cells at this concentration. In an experiment using tumor-bearing mice, oral administration of WSP was begun 24 hours after transplantation of S-180 cells. WSP was administered to the mice 5 times, every other day for 10 days. The doses were 320 mg/kg (10 mg/mouse) or 960 mg/kg (30 mg/mouse) of body weight. All mice were sacrificed 10 days after transplantation, and tumor growth was evaluated. The orally administered WSP significantly inhibited the growth of transplanted tumors (p < 0.05). Furthermore, histological findings revealed a significant reduction in mitotic cells and tumor invasion of the muscular tissue at both dose-levels of WSP.  相似文献   
95.
Since sentinel lymph node(SLN) biopsy has a higher negative predictive value than that of four-node sampling, SLN biopsy might become the new acknowledged standard of clinical care for patients with early breast cancer. SLN biopsy is widely used in Western countries despite the lack of data from randomized trials. Clinical practice guidelines document that SLN biopsy should be performed with prudent informed consent and thorough surgical technique. Before surgeons replace axillary dissection with SLN biopsy as the staging procedure at their institution, they should perform backup axillary dissection until a detection rate of more than 90% and a false-negative rate of less than 5% are achieved. Recently, SLN biopsy has more often been indicated for multicentric breast cancer, larger tumors, prior excisions, and noninvasive carcinoma. While SLN biopsy is widely used in Western countries, there is little experience in Japan. If randomized studies, clinical practice guidelines, and the coverage of lymphoscintigraphy under health insurance were introduced, SLN biopsy would be used more widely in Japan.  相似文献   
96.
Abstract: A simple high-performance liquid chromatographic method that allowsthe determination of 10 biogenic amines and related compounds for crude brain extracts has been developed. The compounds that can be quantified comprise norepinephrine, epinephrine, 3,4-dihydroxyphenylacetic acid, 3-methoxy-4-hydroxyphenylglycol, dopamine, 5-hydroxyindole-3-acetic acid, homovanillic acid, 3-methoxytyramine, 5-hydroxytryptamine and tryptophan. The detection system involves a three electrode-coulometric determination followed by fluorometric determination. This method is highly selective and sensitive, and in the present study, the usefulness of this methodology was confirmed by applying it to the determination of the levels of these various substances in 11 rat brain regions.  相似文献   
97.
Abstract: The relationships between the side effects of maprotiline (MPT) andthe serum concentration of MPT and desmethylmaprotiline (DMPT) were investigated with 27 blood samplings in 15 depressed inpatients. There were significant correlations between the side effects and serum levels of MPT and DMPT. Mild side effects frequently occurred at levels of more than 130 ng/ml of MPT and 70 ng/ml of DMPT. At more than 220 ng/ml of the MPT levels and 110 ng/ml of DMPT levels, severe side effects occurred. Nearly sigmoidalserum level/side effect response curves occurred with both compounds.  相似文献   
98.
Background and Aim: Strip biopsy and endoscopic submucosal dissection (ESD) have been developed as a local treatment for early gastric cancer (EGC). However, the lesion criteria for the use of ESD, rather than strip biopsy, remain to be elucidated. Methods: On the basis of reviews of literature and our observations concerning the outcome of strip biopsy, we set the criteria for selecting strip biopsy and ESD as follows. The indications for strip biopsy were lesions less than 10 mm in size and located in the anterior wall or greater curvature of the lower and middle stomach. ESD was indicated for all other lesions. The validity of the criteria was then analyzed prospectively in 156 patients. The rate of en bloc R0 resection and local recurrence were evaluated. Results: Subsequently, 156 lesions were divided according to the criteria and were endoscopically resected by strip biopsy (n = 13) or ESD (n = 143). The en bloc R0 resection rates for the whole group and the strip biopsy and ESD groups was 93.5% (146/156), 92.3% (12/13), and 93.7% (134/143), respectively. None of the patients had suffered from local recurrence in either the strip biopsy or ESD groups. Conclusion: The validity of our criteria for selecting strip biopsy and ESD was verified. Our criteria exploit the advantages of both procedures and obtain better endoscopic therapy outcomes for EGC.  相似文献   
99.
We previously reported that about 80% of vesicular glutamate transporter 3 (VGLUT3)‐positive cells displayed immunoreactivity for serotonin, but the others were negative in the rat midbrain raphe nuclei, such as the dorsal (DR) and median raphe nuclei (MnR). In the present study, to investigate the precise distribution of VGLUT3‐expressing nonserotonergic neurons in the DR and MnR, we performed double fluorescence in situ hybridization for VGLUT3 and tryptophan hydroxylase 2 (TPH2). According to the distribution of VGLUT3 and TPH2 mRNA signals, we divided the DR into six subregions. In the MnR and the rostral (DRr), ventral (DRV), and caudal (DRc) parts of the DR, VGLUT3 and TPH2 mRNA signals were frequently colocalized (about 80%). In the lateral wings (DRL) and core region of the dorsal part of the DR (DRDC), TPH2‐producing neurons were predominantly distributed, and about 94% of TPH2‐producing neurons were negative for VGLUT3 mRNA. Notably, in the shell region of the dorsal part of the DR (DRDSh), VGLUT3 mRNA signals were abundantly detected, and about 75% of VGLUT3‐expressing neurons were negative for TPH2 mRNA. We then examined the projection of VGLUT3‐expressing nonserotonergic neurons in the DRDSh by anterograde and retrograde labeling after chemical depletion of serotonergic neurons. The projection was observed in various brain regions such as the ventral tegmental area, substantia nigra pars compacta, hypothalamic nuclei, and preoptic area. These results suggest that VGLUT3‐expressing nonserotonergic neurons in the midbrain raphe nuclei are preferentially distributed in the DRDSh and modulate many brain regions with the neurotransmitter glutamate via ascending axons. J. Comp. Neurol. 518:668–686, 2010. © 2009 Wiley‐Liss, Inc.  相似文献   
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