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41.
高效液相色谱法测定人血浆中翁丹西隆浓度   总被引:1,自引:0,他引:1  
建立了翁丹西隆的高效液相色谱测定法。血浆样品用醋酸乙酯萃取,以ZorbaxSilica为固定相,60%0.025mol/L乙酸钠缓冲液(pH4.2)、40%乙腈为流动相,紫外310nm处测定。采用外标法峰高定量。最低检出浓度达1ng/ml,线性范围1.0~40.0ng/ml(r=0.9996),平均回收率为(95.22±3.58)%(RSD3.76%)。用本法测定人血浆中翁丹西隆浓度具有快速、简便、专一性和灵敏度高的优点。  相似文献   
42.
人体肥大细胞的多态性已受到广泛关注,对于肥大细胞分型的研究已成为这一问题的关键。本实验研究了42例人大肠4种肥大细胞类群光镜特征,其中两种为作者的新近发现,暂命名为结缔组织肥大细胞-1(CTMC-1)和粘膜肥大细胞-1(MMC-1)。  相似文献   
43.
本文分析了101例成人骨灰样品和5例成人尸解样品中镭-226和钙的含量。实验范围内,人骨中镭-226含量与年龄及骨中钙含量呈二元线性相关关系。用苏州市人口相应的年龄构成计权的人骨中镭-226含量为(5.99+0.08)×10-4Bq/g灰。所测各部位骨的骨灰中镭-226含量的差异无显著性意义;不同部位骨的灰化率差异甚大,由尸解样品中镭-226含量估算的人体软组织中镭-226负荷量约占全身负荷量的20%。此外,本文还根据所测骨、肺、肝,胃,小肠、大肠、骨胳肌和皮肤中镭-226含量,对相应受辐射危险的组织进行了剂量估算,并估算了接受镭-226及其短寿命子体所致年剂量后随机性健康效应发生的几率,将随机性建康效应发生的几率与世界癌症发病率最低的国家或地区的相应组织或器官的癌症发病率相比较,发现前者比后者至少低约二个数量级。  相似文献   
44.
In 1396 consecutively patch tested patients 18 (1.3%) reacted to Kathon CG. Relevance was established in 4 of the 18 patients. The frequency of positive reactions to Kathon CG in eczema patients seems to have been stable in Denmark during the period 1983 to 1988.  相似文献   
45.
修订车间空气中溶剂汽油容许浓度的研究   总被引:1,自引:0,他引:1  
通过对969例汽油作业工人的体格检查和对86个作业点760次车间内汽油浓度的测定结果表明,在达标的条件下,工人仍有神经衰弱,植物神经功能障碍的临床症状,说明现行车间的卫生标准应当进行修订。根据动物实验资料计算 MAC,180汽油为198.6mg/m~3,120汽油为225.0mg/m~3,二者相差不大,我们建议车间空气中溶剂汽油容许浓度可修订为200mg/m~3。  相似文献   
46.
The present study was conducted to examine changes in water concentration in the ventral prostate of adult rats at different intervals following castration. The prostatic dry weight was obtained by drying the fresh prostate at 70 degrees C for at least 110 hr and the prostatic water content was calculated from its wet and dry weight. Under normal conditions, the prostatic water concentration ranges from 81.9 to 82.7% in uncastrated rats. The prostatic water concentration started to increase at 8 hr postcastration (83.1%) but this increase was not statistically significant. By 16 hr postcastration, the prostatic water concentration (83.8%) became significantly higher than that of the uncastrated animals. In rats of day 1 to day 10 postcastration, the prostate contained significantly more water (84.4%-84.7%) than those in uncastrated animals. By day 21 postcastration, the prostatic water concentration (81.5%) was not significantly different from that of uncastrated rats. Unlike the prostate, the skeletal muscle did not significantly change the water concentration following castration. The 51Cr-EDTA space in the prostate was not significantly different in rats before and after castration. These results indicate that water imbibition in the rat prostate is associated with an active period of prostatic regression and that the change in the 51Cr-EDTA space during prostatic regression is not the major cause of water imbibition in the tissue. Therefore, the present findings suggest that castration-induced water imbibition in the rat prostate is caused by an increase in the intracellular water space.  相似文献   
47.
Whereas water loss in land living animals occurs continuously, water intake takes place discontinuously. At the normal operating set point of plasma osmolality, urine is more concentrated than plasma due to secretion of vasopressin. Thus animals operate around a state of mild dehydration. As water loss occurs, the severity of dehydration and thirst increase in intensity and at some point water intake occurs. Sufficient water is consumed to return plasma osmolality to the normal operating set point. Food intake and water balance are interdependent as food provides the osmoles which determine obligatory renal solute excretion. When dry food with the same osmotic content was substituted for canned food (water content 74%), dogs increased water intake from 24.2 +/- 4.3 to 62.2 +/- 8.8 ml/kg. Urine output and urine osmolality were unchanged, as under conditions of normal hydration, near maximal urine concentration is achieved. Changing water intake is the only available variable to maintain water balance. During water deprivation, the major renal mechanism appears to be natriuresis. In rehydration, satiety mechanisms ensure appropriate water intake and renal sodium conservation restores sodium balance.  相似文献   
48.
ACUTE EFFECT OF ETHANOL ON RENAL ELECTROLYTE TRANSPORT IN THE RAT   总被引:1,自引:0,他引:1  
1. Despite human and animal studies, the direct effect of ethanol on renal water and electrolyte transport is poorly understood. The acute effect of increasing plasma concentrations of ethanol was evaluated in a water diuretic anaesthetized rat model which inhibits endogenous arginine vaso-pressin (AVP) release. 2. Ethanol at a plasma concentration of 1.69 ±0.28 mmol/L produced an immediate increase in urine flow (174 ± 11 μL/min pre-ethanol and 189 ± 13 and then 206 ± 12 μL/min during the ethanol infusion; P<0.001) as well as an increase in fractional sodium excretion (0.17 ± 0.04 to 0.28 ± 0.05 and 0.27 ± 0.05%; P<0.001). There was also a brief phosphaturia. These increases in electrolyte excretion had returned to control values by 20 min despite a further increase in the plasma ethanol concentration. 3. The urinary excretion of potassium, calcium and magnesium was not altered nor was glomerular filtration rate or renal plasma flow. 4. Ethanol at a mean concentration of 1.60 mmol/L did not alter the action of a maximal concentration of AVP (75 ng/kg) on water or electrolyte transport. However, the antidiuretic effect of a submaximal concentration of AVP (7.5 ng/kg) was augmented by ethanol at concentrations of 1.63 and 0.98 mmol/L. 5. These studies suggest that the ethanol induced diuresis commonly ascribed to inhibition of AVP secretion may also be due to other intrarenal effects of ethanol, possibly acting within the proximal tubule. These results also confirm recent in vitro findings that while ethanol does not inhibit the action of a maximal concentration of AVP, it does modulate the effects of lower AVP concentrations.  相似文献   
49.
目的 探讨微量白蛋白尿患病率与心血管疾病危险因素的关系。方法 选择 775例 (男 32 6例 ,女 4 4 9例 )年龄 2 0~ 5 0岁的社区人群 ,测定其体重指数 (BMI)、血压、空腹血糖、血脂谱 ;收集晨尿检测尿白蛋白、尿肌酐浓度 ,并计算尿白蛋白 /尿肌酐的比率。根据有无高血糖、高血压或高三酰甘油 /低高密度脂蛋白胆固醇 (高TG/低HDL C)血症分为 4组 ,即正常组 (A组 )、1种代谢紊乱组 (B组 )、2种代谢紊乱组 (C组 )及代谢综合征组 (D组 ) ,评价微量白蛋白尿与代谢紊乱的关系。结果 ①糖尿病患者微量白蛋白尿的患病率为 2 2 .2 % ,显著高于正常血糖者 (5 .2 % ,P =0 .0 0 2 ) ;高TG/低HDL C血症者微量白蛋白尿的患病率为 8.3% ,显著高于正常血脂者 (4.0 % ,P =0 .0 12 ) ;高血压患者与正常血压者的差异无显著性。②随代谢紊乱加重 ,尿白蛋白浓度显著升高 (协方差分析 ,P <0 .0 1) ,微量白蛋白尿患病率升高 (趋势分析 ,P =0 .0 0 3)。③ 4组间尿肌酐浓度、尿白蛋白 /尿肌酐的差异无显著性。结论 ①糖尿病、高TG/低HDL血症人群的微量白蛋白尿的发病率显著升高。②随代谢紊乱加重 ,微量白蛋白尿患病率亦升高  相似文献   
50.
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