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31.
Excitatory amino acids are presumed to be the transmitter of retinal bipolar cells. However, one of the essential criteria for the identification of the transmitter, its release from the cells upon depolarization, has not been demonstrated. This article examines the release of endogenous excitatory amino acids from bipolar cells and correlates this release with the influx of Ca2+. Bipolar cells with a large, bulblike axon terminal (ON-type cells with mixed inputs from rods and cones) were enzymatically isolated from the goldfish retina. Horizontal cells dissociated from the catfish retina were used as a probe of excitatory amino acids, because these cells can detect submicromolar concentrations of L-glutamate with high selectivity. An isolated bipolar cell was closely apposed to a dissociated horizontal cell, and each cell was voltage clamped by a patch pipette in the whole-cell clamp configuration. When the bipolar cell was depolarized from -60 mV to a potential more positive than -40 mV using a 500-msec voltage pulse, an outward current (greater than 20 pA) was recorded from the apposed horizontal cell, which was maintained at +40 mV. The reversal potential of the current induced by the substance released from bipolar cells (Irs) was close to 0 mV and was almost identical to the responses evoked with ionophoretically applied L-glutamate. Both reversal potentials were shifted to the same, more negative value when the external Na+ was replaced with choline. Furthermore, the Irs was suppressed reversibly by the application of kynurenic acid, a glutamate antagonist. When the Ca current (ICa) of the bipolar cell was blocked by Cd2+, the Irs also disappeared. The peak amplitude of Irs was closely related to that of the ICa. We conclude that mixed rod/cone ON-type bipolar cells of the goldfish retina release an endogenous excitatory amino acid or a closely related compound in a Ca(2+)-dependent manner. 相似文献
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33.
Shinichi Toyooka Hideaki Mori Katsuyuki Kiura Hiroshi Date 《European journal of cardio-thoracic surgery》2008,33(2):315-316
We present a case of a 58-year-old man with diagnosis of lung adenocarcinoma invading the left atrium. He was treated with induction chemoradiotherapy for T4N1M0 disease, showing objective response. Then, a left upper lobectomy with a partial resection of the left atrium was performed without cardiopulmonary bypass. No residual tumor cells existed in the resected specimens, showing pathological complete response. Our case suggests that induction chemoradiotherapy prior to surgery can be an appropriate strategy among carefully selected patients with non-small cell lung cancer invading the left atrium. 相似文献
34.
35.
Mikio Mikami Chisei Tei Kyoko Takehara Shinichi Komiyama Atsushi Suzuki Takanori Hirose 《International journal of gynecological pathology》2003,22(2):205-208
A 38-year-old female presented with a lower abdominal mass. During the operation the mass was found to be retroperitoneal and was excised. Gross examination revealed a mucin-containing cystic lesion with a mural nodule. On microscopic examination, the cystic areas were lined by an invasive mucinous adenocarcinoma and the nodule was composed of an anaplastic sarcomatoid tumor that was immunoreactive for cytokeratin. This present case is the 21st example of a retroperitoneal primary mucinous cystadenocarcinoma and the fourth with a mural nodule. Three of four cases with a mural nodule, including our case, had a rapidly fatal outcome. 相似文献
36.
37.
Kiichiro Hashimoto Naohide Mori Takao Tamesa Toshimasa Okada Shigeto Kawauchi Atsunori Oga Tomoko Furuya Akira Tangoku Masaaki Oka Kohsuke Sasaki 《Modern pathology》2004,17(6):617-622
To clarify the genetic aberrations involved in the development and progression of hepatitis C virus-associated hepatocellular carcinoma (HCV-HCC), we investigated DNA copy number aberrations (DCNAs) in 19 surgically resected HCCs by conventional CGH and array CGH. Conventional CGH revealed that increases of DNA copy number were frequent at 1q (79% of the cases), 8q (37%), 6p (32%), and 10p (32%) and that decreases were frequent at 17p (79%), 16q (58%), 4q (53%), 13q (42%), 10q (37%), 1p (32%), and 8p (32%). In general, genes that showed DCNAs by array CGH were usually located in chromosomal regions with DCNAs detected by conventional CGH analysis. Increases in copy numbers of the LAMC2, TGFB2, and AKT3 genes (located on 1q) and decreases in copy numbers of FGR/SRC2 and CYLD (located on 1p and 16q, respectively) were observed in more than 30% of tumors, including small, well-differentiated carcinomas. These findings suggest that these genes are associated with the development of HCV-HCC. Increases of MOS, MYC, EXT1, and PTK2 (located on 8q) were detected exclusively in moderately and poorly differentiated tumors, suggesting that these alterations contribute to tumor progression. In conclusion, chromosomal and array CGH technologies allow identification of genes involved in the development and progression of HCV-HCC. 相似文献
38.
S. M. Manzurul Haque Kai Chen Noriaki Usui Yasuhiko Iiboshi Hiroomi Okuyama Akira Masunari Riichiro Nezu Yoji Takagi Akira Okada 《Surgery today》1997,27(6):500-505
The purpose of this study was to investigate the intestinal hemodynamics and gut glutamine metabolism during endotoxemia,
and their correlation with altered intestinal absorptive capacity and permeability. Seventeen Sprague-Dawley rats were used
in the study. The endotoxin group (ENDO) recieved endotoxin (10 mg/kg intraperitoneally,n=9), while the control group (CONT,n=8) received saline injection. Twelve hours later, D-xylose (0.5 g/kg) and fluorescein isothiocyanate-dextran (FITC-dextran,
750 mg/kg) were given by oral gavage. One hour later abdominal aortic (AA) blood flow, superior mesenteric venous (SMV) flow,
mean arterial pressure (MAP), central venous pressure (CVP), and SMV pressure (SMVP) were also measured. The MAP, AA, and
SMV blood flow decreased (P<0.05), while the CVP and SMVP increased (P<0.05) in the ENDO group as compared with the CONT group. The ENDO group showed significant decreases for both intestinal
glutaminase activity and net intestinal glutamine uptake (P<0.05). The D-xylose concentration in SMV decreased significantly (P<0.05) in the ENDO group as compared with the CONT group. However, the plasma FITC-dextran concentration showed no significant
difference between the groups. Endotoxin produced a hypodynamic effect in rats 12h after intraperitoneal administration in
association with both a decreased intestinal glutamine metabolism and an absorptive capacity. 相似文献
39.
A 37-year-old man visited our hospital with the chief complaint of a painless mass in subcutaneous tissue of the pubis. We extirpated the localized cyst 2.5 x 4 cm in size. Histological diagnosis was cystic lymphangioma without malignant findings. We reviewed the literature on lymphangioma, a rare disease seldom seen in urological fields. 相似文献
40.
K Imura A Okada Y Fukui H Kawahara M Yagi A Kubota S Kanaya S Kamata Y Nagata 《JPEN. Journal of parenteral and enteral nutrition》1988,12(5):496-504
In 97 neonates receiving total parenteral nutrition in the postoperative period, clinical assessment was made for a newly devised amino acid solution (PF-I-III) from the standpoint of plasma amino acid profile and nutritional effect. These amino acid solutions prepared are characterized by the high concentration of branched-chain amino acids up to 40%, increased arginine and decreased glycine, phenylalanine and methionine as compared with commercially available solutions. In the PF group, each amino acid was kept within the range of standard value. Correlation between plasma amino acid profiles and the dose of each amino acid administered was obtained, from which minimum, standard, and maximum doses for each amino acid was determined. Based on these values, we proposed new formula for neonates which elicits no abnormal plasma amino acid pattern even when amino acids are administered at the dosage level of 1.5-2.5 g/kg/day. 相似文献