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991.
The subdivisions of the sacral intermediolateral nucleus (IML) of the cat have been studied by using a double-labeling technique of retrograde Fluoro-gold (FG) and wheat germ agglutinin-conjugated horseradish peroxidase (WGA-HRP) tracing. The parasympathetic preganglionic neurons (PGNs) that were labeled by the FG injected into the pelvic nerve formed a ‘V’-shaped column known as the sacral parasympathetic nucleus (SPN) in the sacral IML. The neurons that were labeled by the WGA-HRP applied to the lateral parabrachial nucleus (PBL) formed an elongated spindle-shaped column extending throughout the IML of the sacral segments. We designated it by the name of sacral visceral sensory nucleus (SVSN). These findings indicate that the sacral IML of the cat contain two distinct subdivisions, SPN and SVSN. 相似文献
992.
采用直接酶标记法对174例慢性肝炎、重症肝炎和肝癌组织中的HCV抗原进行了检测,HCV 抗原的检出率分别为10.71%、8.10%和2.68%。表明在我国慢性和重症肝病中存在HCV的感染。通过对HCV与HBV 感染关系的研究,发现肝内HBV 标志阳性和阴性者HCV抗原的检出率无明显差异,说明HCV感染与HBV感染之间似无明显关系。 相似文献
993.
对人胚胎晶体γ_2-晶体蛋白溶液用近紫外线(γmax 365nm)照射,不同时间取样分析。利用巯基(-SH)特异性试剂 DACM[N-(7-甲基氨基-4-甲基-3-邻羟苯烯基)-马来酰亚胺],经 SDS-聚丙烯酰胺凝胶电泳观察光照射后的γ_2-晶体蛋白及其聚合物的游离巯基,同时检测照射后的蛋白溶液的紫外吸收光谱、光散射强度、色氨酸荧光发射光谱,以及丙烯酰胺对色氨酸荧光的猝灭效应。结果显示:人胚胎γ_2-晶体蛋白经紫外线照射,使其游离-SH 减少,蛋白聚合和分解,蛋白溶液的光散射增强,其二聚体不含游离-SH,γ_2-晶体蛋白的色氨酸荧光减少,这些变化随照射时间的延长而更明显;而对丙烯酰胺对蛋白分子中的色氨酸荧光猝灭效应影响不大。说明人胚胎γ_2-晶体蛋白通过光氧化,损伤及含游离-SH 的氨基酸残基、色氨酸残基,光氧化促使蛋白聚合和分解.提出通过进一步定量分析,可能在较深层次揭示紫外光氧化损伤含-SH 氨基酸、色氨酸残基,进而影响整个蛋白质分子结构的差异。眼科学报 1993;9:85-89。 相似文献
994.
995.
Da-Nian Zhu, Long-Mei Xue, Peng Li. Effect of central muscarine receptor blockade. with DKJ-21 on the blood pressure and heart rote in stress-induced hypertensive rats.
The experiments were performed on Wistar or Sprague-Dawley rats of both sexes divided at random into stress and control groups. The rats in the stress groups were put into cages and subjected to electric foot-shocks and noises for 9-15 days, which caused an increase in blood pressure (BP) and heart rate (HR). In hypertensive rats DKJ-21 (4mg/lml) was injected intravenously (i.v.), and 0.5-1.0h after administration the BP and HR dropped from the high level to normotensive level. In normotensive rats, however, administration of DKJ-21 had no effect on BP or HR. In separate groups of normotensive rats, pretreatment of DKJ-21 (4 mg/l ml, i.v.) blocked the pressor and tachycardiac effect induced by microinjection of physostigmine (0.4μg/0.1 /μl/site), corticosterone (40μg/0.1μl/site) or aldosterone (40 μg/0.1 μl/site) into the rostral ventrolateral medulla (rVLM). Furthermore, DKJ-21 also attenuated the enhancement of the pressor response to stimulation of the defense area in the midbrain, which was induced by microinjection of drugs (mentioned above) into the rVLM. These results indicate that i.v. DKJ-21 can selectively block the muscarinic receptors in the rVLM in stress-induced hypertensive rats, which suggests that abnormal enhancement of cholinergic mechanism in the rVLM may be related to hypertensive effects of corticoids in this area. 相似文献
The experiments were performed on Wistar or Sprague-Dawley rats of both sexes divided at random into stress and control groups. The rats in the stress groups were put into cages and subjected to electric foot-shocks and noises for 9-15 days, which caused an increase in blood pressure (BP) and heart rate (HR). In hypertensive rats DKJ-21 (4mg/lml) was injected intravenously (i.v.), and 0.5-1.0h after administration the BP and HR dropped from the high level to normotensive level. In normotensive rats, however, administration of DKJ-21 had no effect on BP or HR. In separate groups of normotensive rats, pretreatment of DKJ-21 (4 mg/l ml, i.v.) blocked the pressor and tachycardiac effect induced by microinjection of physostigmine (0.4μg/0.1 /μl/site), corticosterone (40μg/0.1μl/site) or aldosterone (40 μg/0.1 μl/site) into the rostral ventrolateral medulla (rVLM). Furthermore, DKJ-21 also attenuated the enhancement of the pressor response to stimulation of the defense area in the midbrain, which was induced by microinjection of drugs (mentioned above) into the rVLM. These results indicate that i.v. DKJ-21 can selectively block the muscarinic receptors in the rVLM in stress-induced hypertensive rats, which suggests that abnormal enhancement of cholinergic mechanism in the rVLM may be related to hypertensive effects of corticoids in this area. 相似文献
996.
利用紫外吸收光谱、PAGE 垂直板 SDS—PAGE 及快速染色盘状 PAGE 酯酶电泳技术,对人、豚鼠的三种不同皮片的匀浆上清液蛋白成份含量及酯酶同工酶进行了比较分析,旨在为临床上应用新生皮片储皮移植提供理论依据。结果表明,豚鼠皮及人皮皮片匀浆上清液中的蛋白含量、光谱分析、PAGE、SDS-PAGE 及酯酶同工酶电泳,均是新生皮组的变化显著低于其它两组,而-196℃处理组与成年新鲜皮片组存在着较小差别,因此上述免疫生化学指标的判定结果为:新生皮<(差于)-196℃处理成年皮<(差于)新鲜成年皮。 相似文献
997.
Changes in temporal gait characteristics and pressure distribution for bare feet versus various heel heights 总被引:8,自引:0,他引:8
The purpose of this study was to identify changes in temporal gait characteristics and pressure generation across the sole of the foot due to various heel heights in women's dress pumps. Thirty female subjects, aged 18-30 years, volunteered to participate. Subjects were required to have normal gait and to wear comfortably either size 7 or size 9 shoes. Subjects were tested initially in bare feet using electrodynography (Langer Biomechanics Group, 21 East Industry Court, Deer Park, NY 11729-9986) (EDG) at a cadence of ~100 steps/min set by metronome. EDG trials with 4 pairs of shoes were then performed in random order. Shoes were women's dress pumps identical except for heel height. Heel heights were 1.75, 3.12, 5.72 and 8.74 cm. Data were collected over ~ 30 steps and averaged over this period. Data were analyzed using a one-way ANOVA, and changes were only considered significant if the ANOVA identified significant variations bilaterally. Considering temporal gait variables, we concluded that: (1) stance phase was shortened in shoes vs. bare feet but was unaffected by heel height, (2) the percentage of stance spent in weight bearing on the lateral and medial calcaneus decreased above a 3.12 cm heel height, (3) the percentage of stance spent in weight bearing on the first and second metatarsal heads increased in shoes vs. bare feet but was unaffected by heel height, (4) the percentage of stance spent in weight bearing on the fifth metatarsal was less in the 8.74 cm heel than in any other shoe or in bare feet. With regard to pressure variables, we found that: (1) peak pressure under the fifth metatarsal head was inversely related to heel height, (2) pressure under the third metatarsal head peaked earliest in heels greater than 5.72 cm high, and (3) pressure under the medial calcaneus peaked latest in heels greater than 5.72 cm high. 相似文献
998.
本文研究了双酚A对多官能度环氧基和羧基聚丙烯酸正丁酯橡胶增韧环氧树脂的影响。结果表明,加入双酚A,拉伸断裂能有大幅度提高,同时不降低弹性模量。这可能是由椽胶提高断裂伸长与双酚A提高屈服应力产生协同效应的结果。对羧基橡胶增韧的三元共混体系,拉伸断裂能随羧基官能度上升而增加。断裂面的形态研究表明,由于羧基橡胶与双酚A的酯化反应,大大减少了羧基橡胶聚集对增韧的不利影响。 相似文献
999.
紧闭式氧化亚氮麻醉方法的探讨 总被引:2,自引:1,他引:1
25例选择期手术病人采用紧闭式氧化亚氮麻醉方法,术中持续监测呼气末氧和氧化亚氮浓度,脉搏血氧饱和度和呼吸循环指标,术中观察紧闭式麻醉后呼吸末氧化亚氮,氧浓度变化,结果:紧闭式麻醉1,2,3h后氧化亚氮浓度分别为52.7%,56%,64.9%,氧浓度为42.1%,34.4%,30.8%,随麻醉时间的延长,气道压力先降后回升,约3h恢复至紧闭麻醉前的水平,紧闭式麻醉前后在本组观察时间内动脉血气分析提示 相似文献
1000.
本实验以铁骨晶(多肽钙),进口脱脂奶粉,活性钙冲剂,贝壳钙为钙源添加于大鼠正常饲料中。观察结果表明:上述4组钙的吸收率分别为64.4%,69.1%,59.9%,51.6%;钙的储留率分别为89.8%,93.3%,85.2%,79.0%;钙的存留率分别为43.6%,49.0%,32.4%,26.8%;股骨指数分别为7.02×10(-3),6.43×10(-3),6.84×10(-3)。6.88×10(-3);折断力(牛顿)分别为60.54±12.55,46.81±9.32,43.26±16.62,38.24±10.79。同时以铁骨晶为钙源对70例(5~6岁)儿童进行了血清Ca,Fe,Zn,Hb及生长发育的检测。铁骨晶组的身高,体重,胸围分别比对照组增加。铁骨晶组血清Ca,Fe,Zn,Hb也均有较好的改善。这表明铁骨晶具有较好的促进钙吸收利用作用,同时能增加骨强度作用。 相似文献