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951.
SS Agarwal SR Phadke V Fredlund D Viljoen P Beighton 《Canadian Metallurgical Quarterly》1997,72(4):435-439
New procedures of laser therapy and chemotherapy have extended the scope of application of organ-saving treatment at advanced stages of retinoblastoma in childhood, thus making it possible to preserve the eye fully functional or cosmetic. Not having to perform such mutilating procedures as ophthalmectomy or eye socket exenteration contributes to psychological and physical rehabilitation. At the same time, as a comparison of the results of surgery carried out at initial stages and surgery-free treatment showed that palliative therapy is characterized by impressive rates of 5-year survival. New vistas have opened of in the management of pediatric retinoblastoma, particularly in cases of stage III tumor and bilateral involvement. 相似文献
952.
E Tanaka 《Canadian Metallurgical Quarterly》1997,47(3):263-272
The cytotoxic effects of a novel compound, conjugate Se-Pt [(NH3)2Pt (SeO3)] on blood platelet function (aggregation, release of adenine nucleotides) were studied. Contrary to the action of cisplatin or selenite alone, [(NH3)2Pt(SeO3)] did not inhibit ADP-induced platelet aggregation, thrombin-induced release of adenine nucleotides from platelets, and had no effect on the metabolism of platelet arachidonate. The tested compound seems to be less toxic than cisplatin alone, and has no effect on blood platelet activation. 相似文献
953.
Ethanol exposure affects cellular mechanisms involved in the regulation of calcium (Ca2+) homeostasis. Neurotrophins, such as nerve growth factor (NGF), stabilize intracellular Ca2+([Ca2+]i) during a variety of neurotoxic insults. In this study, changes in [Ca2+]i during treatment with ethanol and NGF were measured at the cell body of neurons using the Ca2+ indicator indo-1. Cultured postnatal day-of-birth (P0) septohippocampal (SH) neurons that were labeled with 1,1'-dioctadecyl-3,3,3',3'-tetramethyl-indocarbocyanine perchlorate (DiI), increased [Ca2+]i in response to ethanol. This response was dose-related. P0 SH neurons treated with NGF had lower [Ca2+]i than neurons withdrawn from NGF, implying that NGF may modulate Ca2+ homeostasis in these neurons. NGF also prevented the dose-related increase in [Ca2+]i in ethanol-treated SH neurons. The SH neurons increased [Ca2+]i when they were stimulated with 30 mM potassium chloride (KCl). Ethanol inhibited the potassium-stimulated change in [Ca2+]i but the combination of ethanol and NGF caused [Ca2+]i to increase with 100 mg% and 400 mg% ethanol and to decrease to a lower level with 200 mg% ethanol. These data were compared to data from previously published similar aged medial septal (MS) neurons (B. Webb, S.S. Suarez, M.B. Heaton, D.W. Walker, Clin. Exp. Res. 20 (1996) 1385-1394) and with embryonic gestational day 21 (E21) SH neurons (B. Webb, S.S. Suarez, M.B. Heaton, D.W. Walker, Brain Res. 729 (1996) 176-189). Differences in [Ca2+]i responses were observed in ethanol and NGF-treated postnatal SH neurons compared with P0 MS neurons and E21 SH neurons. Of these differences, most occurred during the combined treatment with ethanol and NGF compared with either treatment alone. 相似文献
954.
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956.
K Sugi N Fujita K Ued K Nawata T Tanaka T Matsuoka Y Kaneda K Esato 《Canadian Metallurgical Quarterly》1997,45(10):1701-1705
The indications for a video-assisted lobectomy are currently ill-defined. Clinicians recommend based on the extent of lymph node involvement. Fifty-nine patients with clinical stage I non-small cell lung cancer underwent lobectomies with systemic lymph node dissections through a standard thoracotomy (Group C), and 26 patients underwent lobectomies with lymph node dissections using the video-assisted procedure (Group V). The number of dissected lymph nodes at all node levels were compared between the two groups. There was no significant difference between groups in the total number of dissected lymph nodes in patients with right lung cancer. The number of dissected hilar and interlobar lymph nodes, however, was less in Group V than that in Group C (hilar: 1.2 +/- 0.4 vs. 2.8 +/- 0.6, interlobar: 1.1 +/- 0.4 vs. 2.1 +/- 0.4). The total number of dissected lymph nodes in patients with left lung cancer was significantly less in Group V than that in Group C (18.5 +/- 0.3 vs. 28.7 +/- 2.4). In addition, the number of dissected lymph nodes in pratracheal, pretracheal, tracheobronchial, subcarinal, hilar, and interlobar lymph nodes were significantly less in the group V than those in Group C. Although there was no significant difference in the actual survival rates between the groups in this preliminary study, a sufficiently small number of dissected lymph nodes in the video-assisted lobectomy may have resulted in inaccurate staging and poor prognosis in these patients. 相似文献
957.
The mouse neurological mutant lurcher (Lc) results from a semidominant mutation. Heterozygous Lc/+ mice are viable but ataxic because Lc/+ Purkinje cells die by apoptosis within the first 3 weeks of life. Lc/Lc mice die shortly after birth. To aid in understanding the function of the lurcher gene product, we have examined the embryonic development of homozygous lurcher animals. The ratio of +/+:Lc/+:Lc/Lc animals did not deviate significantly from the expected 1:2:1. Homozygous lurcher mice at P0 were found to be normal under gross morphological examination. However, these mice weighed less, lacked milk in their stomach, and died within the first day of life. No resorbed embryos were found at embryonic day (E) 17.5, indicating that all homozygous lurchers survived until birth. Histological examination of P0 animals revealed that in homozygous lurcher mice the patterning of the brain is normal but that there has been a massive loss of hindbrain neurons during embryonic development. A particularly conspicuous consequence of the Lc/Lc genotype at birth is the complete absence of large neurons comprising the trigeminal motor nucleus. These neurons arise normally and are maintained until E15.5. However, beginning at E15.5 large numbers of pyknotic cells are evident in the trigeminal motor nucleus, suggesting that these cells die coincident with their terminal differentiation in the developing hindbrain. Because the trigeminal motor nucleus controls muscles required for suckling, these results suggest an explanation for the neonatal death of homozygous Lc animals. These data demonstrate that the severe and dose-dependent developmental consequences of lurcher gene action result from degeneration of distinct neuronal populations on maturation in the developing CNS. 相似文献
958.
Ikeda S. Tanaka T. Amari S. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》2004,50(6):1097-1114
Since the proposal of turbo codes in 1993, many studies have appeared on this simple and new type of codes which give a powerful and practical performance of error correction. Although experimental results strongly support the efficacy of turbo codes, further theoretical analysis is necessary, which is not straightforward. It is pointed out that the iterative decoding algorithm of turbo codes shares essentially similar ideas with low-density parity-check (LDPC) codes, with Pearl's belief propagation algorithm applied to a cyclic belief diagram, and with the Bethe approximation in statistical physics. Therefore, the analysis of the turbo decoding algorithm will reveal the mystery of those similar iterative methods. In this paper, we recapture and extend the geometrical framework initiated by Richardson to the information geometrical framework of dual affine connections, focusing on both of the turbo and LDPC decoding algorithms. The framework helps our intuitive understanding of the algorithms and opens a new prospect of further analysis. We reveal some properties of these codes in the proposed framework, including the stability and error analysis. Based on the error analysis, we finally propose a correction term for improving the approximation. 相似文献
959.
Y Yasuda T Watanabe H Tanaka I Tadashi I Akiguchi 《Canadian Metallurgical Quarterly》1997,99(2):102-105
An animal model of subarachnoid cavity drugs perfusion and its prelimilary clinical application in treatment of acute spinal cord injury (SCI) were reported. Analysis of the heart rate (HR), ECG blood pressure (CVP, CAP) cerebrospinal fluid (CSF) pressuer and CSF gas and pH values of 10 healthy adult goats during subarachnoid daxamethasone verapamil perfusion showed that this model was safe anti reliable. 26 patients with acute SCI were selected for a clinical obseration. Good results were obtained in 7 cases who received this treatment of subarachnoid cavity perfusion with dexamethasone and verapamil. 相似文献
960.
Carinal resection for primary lung cancer--with special attention to a modified double-barrel method
K Yagi Y Miyamoto K Tomiyama M Teramachi K Yamamoto M Omasa T Tanaka 《Canadian Metallurgical Quarterly》1997,45(10):1685-1689
Carinal resection for primary lung cancer was clinically evaluated. Carinal resection was performed in 18 patients, 17 males and one female, with a mean age of 64 years. Nine patients underwent carinal reconstruction and the other 9 sleeve or wedge pneumonectomy. The carinal reconstruction was of the montage type in one patient, the one-stoma type in 2, and the modified double-barrel method in 6. The modified double-barrel method is a technique that we developed by adding bronchial end-to-side anastomosis to the tracheobronchial end-to-end anastomotic site. A pedicled intercostal muscle flap was used for covering the anastomotic site. The postoperative respiratory complications after carinal reconstruction were anastomosis failure in 4 patients (pin-hole in 3) and respiratory failure in 2. However, no anastomosis stricture occurred, and recovery was satisfactory. There were no respiratory complications after pneumonectomy. One patient had renal failure before surgery and died of multiple organ failure 23 days after a montage type carinal reconstruction. The other 17 patients did well and could be discharged from the hospital and the overall mortality rate was 5.6%. No anastomosis stricture occurred in the modified double-barrel method. By carinal reconstruction covering of the anastomotic site is mandatory to prevent fatal postoperative complications. 相似文献