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101.
目的探讨口腔鳞状细胞癌颈淋巴转移范围和临床病理因素间的关系。方法对26例已存在颈淋巴转移的原发口腔癌患者,进行颈淋巴转移范围和患者的临床病理资料的统计分析,寻找影响转移范围的主要因素。结果单因素分析发现,肿瘤生长方式和分化程度与转移范围相关。多因素分析显示,肿瘤生长方式(浸润型)和肿瘤转移范围相关。结论对颈淋巴已有转移的口腔癌患者,若原发灶为浸润性生长,肿瘤倾向于更大范围的转移。对已有颈淋巴转移的口腔癌患者,颈淋巴清扫术范围的制定,主要考虑肿瘤生长方式,适当考虑肿瘤发病部位、厚度、大小和细胞的分化程度,可以不考虑患者年龄和性别。 相似文献
102.
M. W. Oram D. I. Perrett J. K. Hietanen 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1993,97(2):274-294
An investigation was made into the directional sensitivity of cells in the macaque anterior superior temporal polysensory region (STPa) to the motion of objects. The cells studied were sensitive to the presence of motion but showed little or no selectivity for the form of the stimulus. Directional tuning was not continuously distributed about all possible directions. The majority of cells were most responsive to motion in a direction within 15° of one of the three cartesian axes (up/down, left/right, towards/away). Tuning to direction varied in sharpness. For most (34/37) cells the angular change in direction required to reduce response to half maximal was between 45 and 70° (for 3/37 cells it was > 90°). The estimates of the directionality (median I
d = 0.97) of STPa cells was similar to that reported for posterior motion processing areas (the middle temporal area, MT, and the medial superior temporal area, MST). The tuning for direction (sharpness, distribution and discrimination) of the motion-sensitive STPa cells were found to be similar to the tuning for perspective view of STPa cells selective for static form of the head and body. On average the STPa responses showed a 100- to 300-ms transient burst of activity followed by a tonic discharge maintained at approximately 20% of the peak firing rate for the duration of stimulation. The responses of motion-sensitive STPa cells occurred at an earlier latency (mean 91 ms) than responses of cells selective for static form (mean 119 ms), but the time course of responses of the two classes of cell were similar in many other respects. The early response latency and directional selectivity indicate that motion sensitivity in STPa cells derives from the dorsal visual pathway via MT/MST. The similarity of tuning for direction and perspective view within STPa may facilitate the integration of motion and form processing within this high-level brain area. 相似文献
103.
Shohei Takeda Yutaka Inada Yoshiki Ozawa Narue Nakamizo Teruaki Tomaru 《Journal of anesthesia》1995,9(2):176-181
The cardiovascular responses to an infusion of KRN2391, a potassium channel opener, was studied in halothane-anesthetized
dogs. Intravenous administration of KRN2391 at 1.0 and 5.0 μg·kg−1·min−1 for 60 min produced dose-dependent decreases in mean arterial pressure (MAP) and systemic vascular resistance (SVR) associated
with dose-dependent increases in the cardiac index (CI) and stroke volume index (SVI) but was not accompanied by an increase
in heart rate (HR). The maximum decrease in MAP during the infusion of KRN2391 at 1.0 and 5.0 μg·kg−1·min−1 was −13±7% (P<0.01) and −37±10% (P<0.01), respectively. The maximum reduction in SVR after 1.0 and 5.0 μg·kg−1·min−1 was −20±11% (P<0.01) and −60±16% (P<0.01), respectively. A KRN2391 infusion of 1.0 and 5.0 μg·kg−1·min−1 increased Cl a maximum of 11±13% (P<0.05) and 65±33% (P<0.01), respectively. KRN2391 1.0 μg·kg−1·min−1 showed a tendency to increase SVI but this change was not significant, KRN2391 5.0 μg·kg−1·min−1, however, produced a significant increase in SVI. The present results demonstrate that the decrease in MAP and the increases
in CI and SVI caused by KRN2391 are due to a reduction in the afterload. Therefore, we conclude that these cardiovascular
profiles of KRN2391 may be benificial in perioperative uses including the control of systemic blood pressure and the treatment
of hypertension during halothane anesthesia in clinical practice. 相似文献
104.
Akosua N.J.A. de Groot Pieter W.J. van Dongen Tom B. Vree Tom K.A.B. Eskes 《European journal of obstetrics, gynecology, and reproductive biology》1995,60(2):101-107
Objective: To study the pharmacodynamic and pharmacokinetic properties of oral and intravenous methylergometrine upon uterine motility during menstruation. Study-design: Intra-uterine pressure was measured in six volunteers with a fluid-filled sponge-tipped catheter during menstruation. Methylergometrine was given orally (0.5 mg) or intravenously (0.2 mg) in a cross-over design. Results: After intravenous administration, a fast increase of the frequency of uterine contractions and basal tone occurred with a decrease of amplitude, lasting at least 30 min. Oral administration had a late and less marked effect on uterine motility. An intravenous dose administered 24 h after an oral dose had no effect on uterine motility. Pharmacokinetic data, such as the maximum plasma concentration (Cmax), the time at which Cmax is reached (tmax) and the half-life of absorption (t1/2abs) also demonstrated large individual variations after oral administration. Conclusion: Oral administration of methylergometrine had an unpredictable and late effect on uterine motility on the menstruating uterus, probably due to an unpredictable bioavailability, in contrast with the fast and predictable effect after intravenous administration. 相似文献
105.
用小鼠胎肝细胞体外血浆凝块培养红系集落(Erythroid colong formig unit inculturc,E-CFUc)方法,以红细胞生成素(Erythropoietin,EPO)850323为标准试剂,测定正常人、贫血病人血清EPO浓度。实验用妊娠13~15d小鼠胎肝细胞。血清均经透析处理,培养液中加量最大不超过10%。EPO(850323)在培养液中浓度为2.5~100mU/ml。血清EPO(mU/ml)测定结果:28例正常人为48.O±17.7,12例再生障碍性贫血病人为946~>10000,1例巨幼细胞性贫血病人为500,1例缺铁性贫血病人为400和18例慢性肾功能衰竭病人则为94.2±87.6。结果表明:贫血病因对血清EPO浓度有影响。 相似文献
106.
Brian Wm. Davies M.D. Gary A. Pennington M.D. Bahman Guyuron M.D. 《Aesthetic plastic surgery》1993,17(2):125-128
Ambulatory surgery has become routine for many plastic surgery procedures. Anesthesia techniques including general anesthesia by inhalation and intravenous infusion and the dissociative technique have all been used successfully for outpatient anesthesia. Propofol (Diprivan), a relatively new agent, has proven to be a safe and effective general anesthesia agent for outpatient surgery. We report on our experience with propofol as an induction agent and continuous drip for general anesthesia maintenance in 100 consecutive outpatient, plastic surgery procedures performed in an office facility. Assessment factors were recovery-room time, nausea and vomiting in the recovery room and at home, hallucinations, patients' recollection of anesthesia experience, and overall patient satisfaction. 相似文献
107.
Timothy S. Miles 《Clinical and experimental pharmacology & physiology》1994,21(7):511-520
1. The motor unit, consisting of a single motor neuron and the skeletal muscle fibres that it innervates, is the final output pathway of the motor system. 2. Much is now known about the way that human motor neurons are recruited and controlled during voluntary and reflex movements. This review briefly summarizes some of the recent experimental data that has contributed to our present understanding. The review is largely limited to data obtained in human experiments. While much of what we know about the organization of the nervous system has come from studies of the anatomy and physiology of experimental animals, there are some questions that cannot be addressed in reduced animal preparations. The development of new techniques has made it possible to investigate the human nervous system at a level of detail that has not hitherto been possible. 相似文献
108.
109.
低抗凝肝素来源低分子肝素口服制剂的研究 总被引:4,自引:3,他引:1
以生产肝素的副产品——低抗凝肝素为原料,采用亚硝酸控制解聚法制得了低分子肝素,分子量为5300,抗凝活性为39.2u/mg,测定了理化指标。以对家兔实验性血栓形成的影响为药效学指标,确定低分子肝素口服制剂的处方组成为低分子肝素、油酸、牛胆盐。研究了所制备的低分子肝素胶囊对家兔血液流变学及血栓形成的影响,并试用于部分动脉粥样硬化症志愿者,表明该胶囊可有效地改善家免和动脉粥样硬化症志愿者血液流变性质,抑制血栓形成。 相似文献
110.
Oral administration of myelin basic protein (MBP) inhibits clinical and histopathological manifestations of experimental autoimmune encephalomyelitis (EAE), but only partially reduces serum anti-MBP antibody titers. We report here that orally administered MBP alters the isotypic distribution of anti-MBP antibody-forming cells (AFC) among various lymphoid tissues, with the most profound differences seen in mucosal tissues. We observed an isotype-selective reduction in anti-MBP IgA but not IgM AFC frequencies in Peyer's patches. The anti-MBP IgA AFC frequencies could be reconstituted by addition of interleukin 4 (IL-4) and interleukin 5 (IL-5). The cytokines did not appear to generate de novo responses since no increases in anti-MBP IgA AFC frequencies were observed in control cultures. These results indicate that decreased antibody production, as a result of oral antigen administration, can be reversed by exposure to the appropriate cytokines. 相似文献