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91.
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
92.
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
93.
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
94.
Shane L. Carney Alastair H. B. Gillies Cheryl D. Ray 《Clinical and experimental pharmacology & physiology》1995,22(9):629-634
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
95.
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
96.
Andrea Sagripanti Adamasco Cupisti Ugo Baicchi Marco Ferdeghini Giuliano Barsotti 《International Journal of Clinical & Laboratory Research》1994,24(2):113-116
Summary Intraglomerular fibrin deposition has been implicated as an important pathogenetic mechanism in patients with glomerular diseases
and the nephrotic syndrome. To investigate fibrin formation and degradation in nephrosis, we measured fibrinopeptide A by
radio-immunoassay and D-dimer by enzyme-linked immunosorbent assay in the plasma of 30 consecutive adult patients with the
nephrotic syndrome; in 10 the serum creatinine was more than 2 mg/dl. Both fibrinopeptide A and D-dimer were abnormally elevated
in the majority of nephrotics (P<0.001 vs. healthy controls), providing evidence of increased fibrin generation and lysis “in vivo.” A positive correlation
was found between fibrinopeptide A and D-dimer (correlation coefficient 0.64,P<0.001), suggesting a close relationship between fibrin formation and degradation. Calcium heparin, administered to 12 nephrotics,
caused a marked decrease in plasma fibrinopeptide A, due to a reduction of in vivo thrombin activity. As enhanced thrombin
activity can favor fibrin deposition within the renal parenchyma, as well as vascular complications, it is reasonable to assume
that an antithrombotic treatment aimed at controlling thrombin generation may ameliorate the natural history of nephrosis. 相似文献
97.
98.
The effect of calcium dobesilate on venous function following saphenectomy in coronary artery bypass grafting 总被引:1,自引:0,他引:1
Kerim Cagli Kanat Ozisik Mustafa Emir Okan Yurdakok Sami Gurkahraman Vedat Bakuy Muharrem Tola Mustafa Pac Adnan Cobanoglu 《Cardiovascular Revascularization Medicine》2006,7(4):212-216
BACKGROUND: The aim of this study was to determine whether prophylactic use of calcium dobesilate (CD) can improve venous function after saphenous vein harvest in coronary artery bypass graft (CABG). MATERIALS AND METHODS: A total of 100 patients who underwent elective CABG were divided into four equal groups. In Group A, the greater saphenous vein (GSV) was harvested below the knee and, in Group B, through the knee till the groin. These patients remained untreated. Group C received CD in a dosage of 1500 mg po daily after the GSV was harvested below the knee. Group D received same dosage of CD after the GSV was harvested through the knee till the groin. Venous function of ipsilateral leg was evaluated clinically and by Doppler ultrasonography in the postoperative first week and second month. RESULTS: Clinical findings of venous insufficiency were observed with a similar rate between groups at both early and late periods. In Groups A and B, after 2 months, flow velocities decreased and reflux periods increased significantly. In groups C and D, treatment with CD for 2 months after saphenectomy resulted in a significant increase in flow velocities and a significant decrease in reflux periods. Patients in Groups B and D have significantly more impaired venous functions. CONCLUSION: Saphenectomy results in ipsilateral leg venous dysfunction, which seems to be unrelated to leg swelling and to be more prominent in patients with high-level saphenectomy. In addition, to be careful about the restriction of the saphenectomy procedure into the most appropriate level, prophylactic use of CD can prevent this deterioration when it was added to varice socks. 相似文献
99.
100.