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991.
The use of atropine to control heart rate responses during detomidine sedation in horses 总被引:2,自引:0,他引:2
Detomidine is a sedative-analgesic which has a pharmacological profile similar to xylazine. There is evidence that the sedative effects are mediated through alpha-2 adrenoceptors.Cardiopulmonary responses were determined using detomidine as the principal agent and as a preanesthetic prior to the induction of general anesthesia. Compatibility with guaifenesin, sodium thia-mylal and halothane were determined.As in the case of xylazine, detomidine produces a slowing of heart rates. This was found to be either sinus bradycardia or heart block. There may be a corresponding increase in systolic blood pressures. The respiratory pattern is altered through the arterial blood gases and pH data supported evidence of adequate ventilation. The heart rate response to detomidine without anticholinergic treatment was transient and related to he duration of drug action.Atropine sulfate, 0.02 mg/kg i.v. was effective in preventing or treating bradycardia or heart block from detomidine. Heart rates also increased during the administration of guaifenesin and sodium thia-mylal when given 50 min poisit-detomidine. 相似文献
992.
金仲辉 《中国农业大学学报》1989,(3):340-345
本文讨论了双向反射率分布函数、双向反射率、双向反射率因子等光谱反射率之间的关系,并指出了在一定条件下,遥感技术中野外测量地物反射光谱所得的双向反射率因子和物理学中惯用的光谱反射率即半球反射率定义(全部反射光功率与入射光功率之比)是完全一致的.最后还讨论了在野外测量地物反射光谱时需要注意的几个具体问题. 相似文献
993.
透明质酸(HA)的功能性及生产技术研究进展 总被引:6,自引:0,他引:6
透明质酸 (Hyaluronicacid简称HA)是一种国际上公认的生物大分子保湿剂 ,用于眼科显微手术、关节炎治疗、高级化妆品、妇产科等领域。综述了目前国内外对透明质酸的化学结构、理化性质、应用及生产方法等方面的研究现状 ,对透明质酸的线性结构、超强吸水性以及它与水结合成的弹性透明水化膜在润肤、恢复软组织及妇产科临床方面的应用作了较详细的论述 ,对采用动物组织为原料的提取法和采用兽疫链球菌等为菌种的发酵法作了系统总括 相似文献
994.
水蚀地造林树种生态适应性研究 总被引:1,自引:0,他引:1
为了给水蚀地造林选择树种提供科学依据,根据北纬24°39'—30°08'东经108°47'-114°15'范围内的1386个标准地和12个树种的68株林木根系资料,采用定性和定量分析相结合的方法,提出了亚热带水蚀地上20个树种对土层厚度的生态适用极限值;极限为0—5cm的有Pinusmassaniana等11个树种,6—10cm的有Dalbergiahupeana等7个树种,21—30cm的有Cunninghamialanceolata等2个树种。极限值小的树种根系有较大的根幅和分布深度,并具匍匐于岩石表面浅土层和沿裂隙生长延伸的特性。土层、土层加母质层厚度和坡位对水蚀地生长的影响较大。各生态因子对不同树种的贡献虽有相似性,但仍有差别。生态因子对D5的影响全部达显著或极显著水平的树种有Sassafrastzumu等,部分达显著或极显著水平的树种有Pistaciachinensis等。 相似文献
995.
996.
ZHENG Xin ZHANG Tong-hu QIN Yong-we ZHANG Guo-yuan WU Yue-fen HU Yun-fen 《园艺学报》2001,17(12):1179-1183
AIM: To study the relationship between cardiac extracellular matrix remodeling and cardiac function after myocardial infarction. METHODS: We observed sequential changes in collagen contents and collagen Ⅰ/Ⅲ ratios in infarct zone (IZ) and non-infarct zone (NIZ) and their relationship to the parameters of left ventricular systolic and diastolic function in the rat model of myocardial infarction induced by ligation of left main coronary artery. RESULTS: Collagen conteants in IZ and NIZ after 3d of myocardial infarction were significantly higher than those in sham group at corresponding time (P<0.05, P<0.01). Collagen Ⅰ/Ⅲ ratio in IZ decreased on day 3, significantly increased after 7 d (P<0.01). Collagen Ⅰ/Ⅲ ratio in NIZ increased significantly afte14 d. Correlated analysis between collagen contents in IZ or NIZ and collagen type Ⅰ/Ⅲ ratio and maximal ascending velocity (+p'max) or maximal descending velocity of the left ventricular pressure (-p'max) was performed and the negative correlation between collagen contents in NIZ and +P'max (r=-0.589, P>0.05) and -P'max (r=-0.788, P<0.01) was found. Collagen content in IZ positively correlated to the +P'max (r=0.70, P<0.50), but not to -P'max (r=-0.29, P>0.05). Collagen type Ⅰ/Ⅲ ratios in NIZ correlated negatively to the +P'max (r=-0.504, P>0.05) and -P'max (r=-0.545, P>0.05), but there were no relationship between collagen type Ⅰ/Ⅲ ratios in IZ and +P'max or -P'max in IZ. CONCLUSION: Collagen deposition in IZ after myocardial infarction was of benefit to improvement of systolic function. Collagen deposition in NIZ was harmful to systolic and diastolic function. 相似文献
997.
Immune function in dairy cows related to energy balance and metabolic status in early lactation 总被引:1,自引:0,他引:1
Two feeding experiments were carried out in 2 successive years with 28 cows of the Norwegian Red Cattle (NRF) in each experiment. The cows were randomly distributed into 4 groups and subjected to different feeding regimens from 1 month prior to calving until 12 weeks after calving. The experimental design was factorial (2 x 2) with respect to protein content of the concentrate (17.5% digestible crude protein (DCP) v.s. 12.5% DCP) and concentrate allowances (standard v.s. substandard allowances after calving). Silage was offered ad libitum. Samples for estimation of serum immunoglobulin-G, white blood cells and lymphocyte responses to the mitogens phytohemagglutinin, concanavalin A and pokeweed mitogen were collected 4 weeks prior to expected calving, and 2, 4 and 8 weeks after calving. The levels of milk immunoglobulin-G were estimated at calving and 2, 4 and 8 weeks after calving. A significant positive relationship was found between the estimated energy balance and the lymphocyte response to mitogens. Little evidence was found for the existence of a significant relationship between the immunologic parameters and plasma indicators of metabolic status. The lymphocyte response to phytohemagglutinin and levels of serum immunoglobulin-G increased, while levels of milk immunoglobulin-G decreased during the period from calving to 8 weeks after calving. Increased milk somatic cell counts were associated with a significant decrease in the lymphocyte responses to mitogens. 相似文献
998.
Frances J. Barr MA VetMB Mark W. Patteson MA Vetmb Vanda M. Lucke BVSc PHD Christine Gibbs BVSc PHD 《Veterinary radiology & ultrasound》1989,30(4):169-173
Persistent hypercalcemia in the dog is most commonly seen as a paraneoplastic syndrome or in association with widespread osteolytic lesions. In high concentrations calcium is a potent nephrotoxin and may cause severe and irreversible renal damage. The ultrasonographic changes in the kidneys of three dogs with hypercalcernic nephropathy are described'and compared with the changes described in the same human condition. It is suggested that ultrasound could be a useful technique for evaluation of the severity of renal damage and the potential return of renal function in such instances. 相似文献
999.
DG3型割灌机振动的实验研究 总被引:2,自引:2,他引:0
该文对国产DG3型割灌机的振动频谱以及各振源点与手柄间的振动传递函数进行了实验分析.结果表明,在工作转速(6000r/min)下的振动加速度几乎都集中在60~200Hz范围内,并且76Hz,100Hz和152Hz是3个主要支配性峰值,它们是减振的主要对象频率;轴承B1,B2,B3处与手柄A点的振动传递函数值比其它大,而且B1的影响最主要;长轴上各激振点上下方向(z方向)与A点左右方向(x方向)之间的传递函数在60~80Hz之间存在一个峰值 相似文献
1000.
在分析国家和新疆自治区重点扶持的贫困县———墨玉县农业生态系统的水土资源结构、农业种群结构和产业结构的基础上,对其绿洲农业生态经济系统进行了能量流、物质流和价值流的分析。结果显示其水土资源结构不平衡、种群结构单一、产业结构不甚合理,决定了绿洲功能较差,产投比低下的特点,并据此从可持续发展的角度提出了以发展生态农业为中心,改善绿洲农业生态经济系统结构并提高其功能的对策与建议。 相似文献