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121.
影响松毛虫赤眼蜂性比的因素 总被引:2,自引:1,他引:2
本文用柞蚕卵作室内繁殖松毛虫赤眼蜂的代寄主进行有关影响该蜂性此因子测定。试验在雌蜂不同年龄、寄主卵量、和雌蜂密度等三方面进行。结果表明,一粒柞蚕卵被超过4头雌蜂寄生时,产卵量多,未能完成发育子代数亦增加,而羽化率低,子代雌蜂比例下降。说明过少的寄主卵,复寄生机会增多,成蜂性比受影响。 相似文献
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在小麦含水量分别为9.3%、12.6%和14.4%,装满度分别为100%、70%、50%、30%和0%,气体浓度为100mL/m3和400mL/m3的条件下,测定小麦对磷化氢的吸附率,结果表明小麦对磷化氢的吸附率随着粮食水分增加,磷化氢浓度和装满度增大有不同程度增加.在药量较大的施药初期和装满度大时,检测到的磷化氢浓度高于设定浓度,磷化氢浓度、小麦水分和装满度较低时,小麦对磷化氢的吸附较容易达到平衡. 相似文献
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二元杀虫剂混配比例与共毒系数的关系 总被引:1,自引:0,他引:1
在二元杀虫剂混配中,共毒系数与某种农药在混剂中所占的比例关系是一条曲线。这个公式初步推断为y=ax2+bx+c。 相似文献
127.
饲粮蛋白能量比值与产蛋鸡脂肪肝综合症发生率的关系研究 总被引:5,自引:1,他引:5
采用每千克含2.59、2.64、2.70及2.75兆卡的4个代谢能水平的配方,饲喂产蛋鸡,结果证明,日粮蛋白质与代谢能之间的比值大小,对鸡的生产性能和鸡脂肪肝综合症的发生率影响较大。试验1~4组蛋能比值依次为66.94、64.77、62.74及60.97,脂肪肝综合症的发生率相应为30%、 10%、 10%和0,其相关性极为显著(r=0.79);产蛋性能:第二组产蛋量最高(平均每羽16.49千克),第一组次之,第四组最低(15.36千克)。 相似文献
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Gieger TL Feldman EC Wallack ST Dank G 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2003,17(2):154-157
Many dogs with chronic illness have serum biochemical abnormalities consistent with hyperadrenocorticism (HAC). Lymphoma (LSA) is a chronic disease of dogs. The purpose of this study was to evaluate adrenocortical screening test results in dogs with LSA to evaluate their specificity. Criteria for inclusion in the study included a diagnosis of LSA, an expected survival time of 16-56 weeks, no glucocorticoid treatment beyond 4 weeks after the initiation of chemotherapy, no evidence of HAC, and owner consent. Post-ACTH stimulation plasma cortisol concentrations (PACs), urine cortisol : creatinine (UC : Cr) ratios, and maximal left adrenal width measurements were performed at the time of LSA diagnosis before the initiation of chemotherapy and at 16, 24, 32, 40, and 52 weeks or until the loss of remission or the development of another disease. Ten dogs met the criteria for inclusion. Forty-two PACs were performed; 1 abnormal, 2 borderline, and 39 normal values were detected. Thirty-five maximal left adrenal width measurements were obtained; 0 abnormal, 5 borderline, and 30 normal measurements were detected. Thirty-six UC : Cr ratios were obtained, with 26 abnormal, 4 borderline, and 6 normal values detected and 9 of 10 dogs having at least 1 abnormal value. These data suggest that in dogs with LSA, the UC : Cr ratio frequently is abnormal and may not be a specific test for HAC, or it may be the most sensitive test for increases in cortisol secretion due to chronic illness. Maximal left adrenal width measurements and PACs were almost always normal and may be more specific for HAC or less sensitive for demonstrating chronic increases in cortisol secretion. 相似文献
130.
Stepien RL Rapoport GS Henik RA Wenholz L Thomas CB 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2003,17(1):65-72
Comparison of test characteristics allows a clinician to choose the optimal diagnostic test method for an individual patient. This study assessed the comparative test characteristics of noninvasive (NI) blood pressure measurement methods (oscillometric and Doppler) and used this information to develop optimal cutoff values for diagnosis of systolic hypertension in dogs by these NI methods. Simultaneous NI (oscillometric or Doppler methods) and invasive (arterial puncture [AP]) systolic blood pressure (SBP) measurements were obtained prospectively from normal dogs and dogs suspected of having systemic hypertension based on clinical signs. Oscillometric SBP readings were obtained from the distal hind limb (Osc-L, n = 54) or the proximal tail (T. n = 27). Doppler BP measurements were obtained using a forelimb cuff (n = 57). AP-SBP was categorized as hypertensive if > or = 160 mmHg, and sensitivity (Se). specificity (Sp), and likelihood ratios (LR) were calculated for diagnostic cutoff values ranging from 130 to 220 mmHg. Receiver operator characteristic (ROC) curves were analyzed to determine optimal cutoff values for diagnosis of AP-SBP > or = 160 mmHg. Optimal NI SBP cutoff values considered to reflect AP values > or = 160 mmHg were: Osc-L = 160 mmHg (Se: 65%, Sp: 85%. LR = 4.33: 1), Osc-T = 150 mmHg (Se: 84%, Sp: 75%, LR = 3.36: 1), and Doppler = 160 mmHg (Se: 71%, 相似文献