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41.
Direct evidence is given that reserpine, in concentrations of 0.125 to 0.625 mM, effects a release of noradrenaline from a suspension of transmitter granules isolated from bovine splenic nerves.  相似文献   
42.
Concentric microelectrodes were used to voltage-clamp spinal motoneurons. With depolarizing voltage steps, current transients often appear, with some latency and in all-or-none fashion. Voltage-current relations indicate a two- to threefold reduction in resistance between inside and outside when the cell fires. These results suggest that activity does not involve the whole soma-dendritic membrane.  相似文献   
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To investigate the potential effects of wastewater sludge and sludge biochar on growth, yield and metal bioaccumulation of cherry tomato ({\it Lycopersicon esculentum} L.), a pot experiment was carried out under greenhouse environment with three different treatments, control soil (CP), soil with wastewater sludge (SS) and soil with sludge biochar (SB), to reveal the comparative effect between the amendments of wastewater sludge and sludge biochar.~The soil used for pot experiment was Chromosol.~Wastewater sludge and sludge biochar produced through pyrolysis process at 550 $^\circ$C were applied at 10 t ha$^{-1}$. No significant difference was found in growth and production of cherry tomatoes between wastewater sludge and sludge biochar applications to the soil. The accumulation rates of metals in the fruits were lower in the treatment with sludge biochar than in the treatment with wastewater sludge. The study highlights the benefits of risk mitigation from toxic metal accumulation in fruits using wastewater sludge and sludge biochar as soil conditioners.  相似文献   
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Case records and radiographs of 37 dairy cows presented to the University of Illinois Veterinary Medicine Teaching Hospital with a diagnosis of cranial cruciate ligament rupture were reviewed. Signalment, history, duration of lameness prior to clinical presentation, and physical examination findings were evaluated. Survey radiographs were examined and radiographic lesions were documented. Individual cows were classified into groups (A, B, C) based on the severity of radiographic lesions, with Group A cows having minimal radiographic lesions. Cows in Groups A and B had radiographic lesions similar to Class I in beef bulls reported in another study.3,4 An attempt was made to relate the severity of radiographic lesions with age and duration of lameness. Group A animals tended to be younger cows (x?= 4.58 years) with a short duration of lameness. Group B cows were older (x?= 7.87 years) with a somewhat longer duration of lameness. Group C cows were slightly younger (x?= 7.30 years) than Group B cows; however, their duration of lameness was much longer (x?= 57.2 weeks vs 6.35 weeks for Group B and 2.54 weeks for Group A). The pathogenesis of cranial cruciate ligament rupture and its associated lameness appeared to differ in dairy cows from beef bulls. The majority of animals in this study had radiographic lesions of mild to moderate severity (Groups A and B). In contrast, based on previous work, beef bulls had a greater tendency to be similar to our Group C designation. Beef bulls became lame with cranial cruciate ligament rupture only after severe lesions of degenerative joint disease had already occurred. It has been stated that lameness associated with cranial cruciate ligament rupture in the beef bull is, therefore, secondary to degenerative joint disease. In contrast, the syndrome in dairy cows, as evidenced here, differs, since they often presented with cranial cruciate ligament rupture with little or no radiographic evidence of degenerative joint disease.  相似文献   
47.
Twenty-three canine pelves were tested bilaterally to determine the stiffness and strength of intact ilium and stabilized oblique iliac osteotomies that simulated a common clinical fracture. Fixation systems tested were three 4.0 mm cancellous screws inserted ventral to dorsal across the osteotomy site and one laterally placed five hole 3.5 mm dynamic compression plate. Specimens were mechanically tested to failure under torsional, axial, or axial plus bending loads. Lag screw fixation was stiffer and stronger than plate fixation in all testing modes. The differences were statistically significant (p less than .05) in the torsional and axial plus bending loading modes. Fatigue testing was performed on implanted specimens with low-level cyclic loading under axial plus bending loading conditions. Physiologic loading conditions failed to produce mechanical failure of either fixation system after 100,000 cycles.  相似文献   
48.
21世纪上半叶,中国处于城镇化快速发展阶段,新型城镇化的概念也在这一时期提出,以应对过速城镇化产生的问题.本文在系统阐述新型城镇化面临的诸多挑战的基础上,聚焦作为城镇弱势群体之一的城镇少数民族,提出大力加强城镇少数民族参与新型城镇化过程应是今后政府工作的重点之一.作者提出公众参与的地理信息系统(PPGIS)作为促进城镇少数民族参与城镇建设的新媒介,将在提高少数民族融合程度方面发挥积极广泛的作用,应予以关注并推广.  相似文献   
49.
Biomechanical analysis was performed on the cranial cruciate ligament (CCL) and three autogenous tissues used for CCL reconstruction in the canine stifle. The autogenous tissues were patellar ligament-based autografts described for over-the-top CCL replacement and included the central one third of the patellar ligament, the medial one third of the patellar ligament, and the lateral one third of the patellar ligament with fascia lata. Tension testing produced abrupt failure of the central and medial autografts but sequential failure of the lateral autograft. Structural properties were determined for the overload condition and within the load range of normal activity for the CCL (physiologic range). None of the autograft systems approached the stiffness, maximum load, and energy absorbed to maximum load of the CCL. The central and lateral autografts were stiffer, had greater maximum loads, and absorbed more energy to maximum load than the medial autograft. The central and lateral autografts had an elastic range, as defined by proportional limit, which corresponded to the physiologic range of loading for the CCL. Loads that corresponded to physiologic displacement of the lateral and central autografts were near the maximum load of the fixation site, which underscored the need for postoperative support of the repaired stifle.  相似文献   
50.
Gentamicin pharmacokinetics in diabetic dogs   总被引:1,自引:0,他引:1  
Reduction of the prolonged terminal elimination phase of gentamicin may be caused by diabetes mellitus, irrespective of the model of diabetes. To test this hypothesis, five normal dogs, three dogs with alloxan-induced diabetes mellitus, and four dogs with naturally occurring diabetes mellitus (all of which were given exogenous insulin to control hyperglycemia) were given 4.4 mg/kg gentamicin intravenously. Serum pharmacokinetics were analyzed using non-compartmental pharmacokinetics assuming a sum of exponential terms. Gentamicin pharmacokinetics during the first 8 h were the same in normal and diabetic dogs. Over 7 days, MRT in normal dogs (5830 +/- 2970 min, mean +/- SD) was longer (P less than 0.01) than in diabetic dogs (136 +/- 164 min). In diabetic dogs, Cls was greater (3.01 +/- 0.86 ml/min/kg) than in normal dogs (1.45 +/- 0.11 ml/min/kg; P less than 0.01), whereas Vd(ss) was smaller in diabetic dogs (0.405 +/- 0.508 l/kg) than in normal dogs (8.56 +/- 4.48 l/kg; P less than 0.01). Serum gentamicin concentrations were less than 0.020 microgram/ml by 2 days in all of the diabetic dogs, but were 0.048 +/- 0.018 microgram/ml at 7 days in normal dogs. Thus, diabetes mellitus, either induced by alloxan administration or naturally occurring, abolished the terminal elimination phase of gentamicin disposition in a non-rodent species.  相似文献   
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