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121.
对三年生番荔枝(Ancnona squamosa L.)实生树的开花生物学和人工授粉进行了研究并发现;番荔枝的花有两荔异熟现象,人工授粉能提高座果率,简便而有效的方法是用毛笔直接从树上花药自然裂开的花上聚花粉并立即授在花药没裂开的花上,授粉后两周的座果率达87.9%,授 在花药裂开的花上,座果率为5.3%,与对照照座果率4.4%没有区别,说明花药裂开柱头容受性完全消失,花药裂开时间与品种特有关,目前,广东栽培的番荔枝分为花药早上裂开和傍开两种类型,这两种类型的不同品种之间授粉也能提高座果率,授粉后两周的座果率为83.3%。说明花裂开关12h柱头容受性仍完全正常。  相似文献   
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The efficacy and toxicity of the siderophore desferrithiocin (DFT), which has shown potential application in iron chelation therapy, were assessed in vivo and in vitro. DFT was evaluated in vivo in two ways: firstly, by measuring the effect of a single dose of DFT (10-100 mg/kg) on 59Fe excretion in iron-loaded rats labelled with 59Fe; and secondly, by examining the effect of the daily oral administration for 2 weeks of DFT (10-25 mg/kg/d) on the growing rat. DFT and its ferric complex, ferrithiocin (FT), were assessed in vitro from their effects on transferrin and iron uptake and mobilization from rat hepatocytes in culture using transferrin doubly labelled with 125I and 59Fe. Both oral and subcutaneous DFT were highly effective in promoting iron excretion in vivo, but showed evidence of toxicity after oral administration for 2 weeks at 25 mg/kg/d. In addition, DFT was much more effective than desferrioxamine or pyridoxal isonicotinyl hydrazone in reducing hepatocyte iron in vitro. However, FT was cytotoxic, causing membrane disruption and release of intracellular aspartate aminotransferase. It was concluded that DFT should not be considered for chronic iron chelation therapy without extensive further evaluation.  相似文献   
124.
R K Chan  Y S Chan  T M Wong 《Brain research》1991,549(1):118-126
Single unit activities were recorded from the rostral ventrolateral medulla (RVL) of pentobarbital-anesthetized normotensive Wistar Kyoto rats (WKY) and spontaneously hypertensive rats (SHR). Throughout the recording period, arterial blood pressures of WKY (mean arterial pressure, MAP = 103.1 mm Hg) and SHR (MAP = 159.2 mm Hg) remained stable at the respective basal levels. The units recorded in this study were all spontaneously active and cardiac-locked. Two types of discharge patterns, namely single and double discharges, were identified. These single and double discharge units were found to distribute randomly in RVL. In WKY, 92.6% of RVL neurons exhibited single discharges whereas in SHR, the majority (57%) of RVL neurons exhibited double discharges. The mean firing rate of single discharge units in RVL of SHR was significantly higher than that of WKY, whereas the mean firing rate of double discharge units in WKY was similar to that of SHR. About half of the units studied were also tested for antidromic collision; all units tested could be antidromically activated from the intermediolateral column (IML) of the thoracic spinal cord and the lowest threshold sites were consistently localized within IML. In both groups of rats, the axonal conduction velocity of RVL neurons showed a bimodal distribution viz. the fast and slow conducting axons. The mean conduction velocities of each of these two groups of neurons in WKY and SHR were similar. Most of the double discharge units in WKY and SHR belonged to the fast conducting type.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
125.
The purpose of this study was to compare the effects of exercise and/or caloric restriction for 12 wk on body composition, maximal aerobic power (VO2max), and serum lipids and lipoproteins in overweight individuals. Forty-eight males and 48 females (means age = 36.6 yr), 120-140% of ideal body weight, were randomly assigned to groups (N = 12 each) of diet-exercise (DE), diet (D), exercise (E), and sedentary control (C). The dietary regimen consisted of 1,200 kcal X d-1, while exercise consisted of 5 d X wk-1 of 30 min of walk/running. For the males, body weight (BW) and fat weight loss in the DE group (-11.8 and 23%, respectively) were significantly greater than in the D group (-9.1 and -18%), with both groups significantly greater than for E and C. In the females, BW and fat weight loss for DE (-10.4 and -24%) were significantly greater than for D (-7.8 and -20%), with both groups significantly greater than E and C. Both DE and D males and females had a decrease in fat-free weight of -4.5 and -2.4%, respectively. In both sexes, the increase in VO2max-BW (ml X kg -1 X min-1) in DE (25%) was significantly greater than for E (15%), D (11%), and C (0%), with differences between E and D nonsignificant. However, increases in absolute VO2max (1 X min-1) and VO2max-fat-free weight (ml X kg-1 X min-1) were similar (P greater than 0.05) for DE and E (14%) but significantly greater compared to D and C (2%).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
126.
127.
运动性疲劳中医肾虚证的辨证分型及其诊断标准   总被引:1,自引:0,他引:1  
目的:阐明运动性疲劳中医肾虚证的主要证候及辨证标准。 方法:于2003-07/2004-01选择湖南省水上运动训练基地的皮划赛艇运动员和省体工大队的田径运动员共199名为研究对象。将中医辨证理论方法与流行病学调研疗法有机结合,统一诊断标准和资料处理方法,分析肾虚各证候构成比,进行聚类分析,观察单一症状出现频次、症状组合出现频次。 结果:纳入受试对象199名,均进入结果分析。①肾虚常见证候有腰脊酸痛,头晕目眩,精神疲倦,四肢乏力,胫膝酸软,气短自汗,五心烦热,口干少津,畏寒肢冷,小便清长,夜尿频多,少寐多梦。②肾虚各证候构成比:肾气虚(51.26%)、肾阴阳两虚(37.69%)、肾阳虚(6.53%)、肾阴虚(4.52%)。③聚类分析:第一类为腰脊酸痛,精神疲倦,四肢乏力,气短自汗;第二类为头晕目眩,胫膝酸软,畏寒肢冷,小便清长,夜尿频多;第三类为五心烦热,口干少津;第四类为少寐多梦。④参与组合频次大于50%的症状主要是:精神疲倦、四肢乏力、腰脊酸痛、头晕目眩、气短,这5个症状也是单个症状频次大于80%的。 结论:运动性疲劳中医肾虚证的常见证候为肾气虚、肾阴阳两虚、肾阳虚、肾阴虚。而肾气虚是运:动性疲劳中医肾虚的主要证候。精神疲倦、四肢乏力、腰脊酸痛、头晕目眩、气短这5个症状可以作为运动性疲劳肾气虚辨证标准中的主要症状。  相似文献   
128.
The effects of the bisbenzylisoquinoline alkaloids tetrandrine and berbamine on the action of IL-1, TNF and PAF were investigated in the rat subcutaneous air pouch model of inflammation. Both compounds were equipotent in the suppression of leukocyte infiltration into air pouches induced by IL-1 and TNF, with ED50 values in the range 20–30 mg/kg/3 days. Both were also equiptent in suppression of PMN infiltration induced by PAF with ED50 values in the same range as that for IL-1 and TNF. However, tetrandrine was more potent than berbamine as a suppressant of PAF-induced MNC infiltration, but much less potent than berbamine in carageenen-induced PMN infiltration. These results suggest that these bisbenzylisoquinolines may have value in the therapy of chronic inflammatory diseases where IL-1, TNF and PAF have a role in pathogenesis.  相似文献   
129.
130.
复方珍珠口服液由珍珠、黄精、枸杞子、何首乌、熟地黄等多种补益中药材组成,提取制备而成的口服液,经临床144例验证表明,该口服液具有滋补肝肾、养血活颜、延缓衰老的功能。对肝肾两虚、头晕眼花、健忘、夜尿、病后体弱,高胆固醇、高血压症有较好的疗效;其中治疗肾虚证总有效率为95.83%,治疗高血压症总有效率为80.9%,治疗高胆固醇总有效率为71.47%。  相似文献   
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