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801.
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南疆香梨园生草覆草效应研究 总被引:2,自引:0,他引:2
南疆光热资源充足 ,但水资源短缺 ,严重制约了农业的发展。为此 ,连续 5a(年 )对香梨园进行了生草覆草试验。结果表明 ,覆草能显著提高香梨产量和品质 ,5a(年 )间的年均增产幅度为1 5 .2 %~ 65 .3 % ,节水幅度达到 2 8.8%~ 3 6.1 % ,土壤有机质含量增加 2 5 .6%~ 70 .5 % ,速效氮、速效钾和速效磷的含量分别增加 3 9.1mg/kg~ 76.4mg/kg、4.5mg/kg~ 1 8.0mg/kg、2 9.8mg/kg~76.9mg/kg,0~ 3 0cm土层 1 0 .0mm直径总根数增加幅度达到 5 5 .0 %~ 1 2 2 .1 %。经济效益分析表明 ,以苜蓿生草覆草最宜 ,5a(年 )年均增产 75 1 4.3kg/hm2 ,年增收入达到 5 0 0 8.85元 /hm2 ,节水效益达到 5 0 8.5 5元 /hm2 ,省肥效益达到 1 95 0元 /hm2 ,产投比为 5 .67∶1。 相似文献
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805.
不同施肥期沾化冬枣对15N的吸收、分配及利用特性 总被引:14,自引:1,他引:14
盆栽条件下利用15N示踪技术, 研究不同时期施15N - 尿素, 对沾化冬枣15N的吸收利用及分配特性的影响。结果表明: 生长季前期(萌芽前和花前) 施用15N - 尿素, 经根系吸收后, 15N优先分配到贮藏器官(包括主干、多年生枝和粗根) 中, 然后外运用于树体新生器官(包括枣吊及其叶片、新生营养枝、细根及果实) 的形成, 果实采收后15N开始向贮藏器官回流; 果实硬核期15N直接用于树体营养生长和生殖生长, 而不是先贮藏再利用; 果实速长期15N优先向贮藏器官中积累; 萌芽前施15N在树体内的运转规律符合落叶果树贮藏N营养分配规律, 优先转运到生长中心。随着施肥期的后延, 植株对15N - 尿素的当季利用率逐渐下降。 相似文献
806.
D. W. Knapp B. Filion M. C. Filion N. C. Phillips 《Veterinary and comparative oncology》2005,3(1):46-47
Introduction: Mycobacterial cell wall‐DNA complex (MCC) is a bifunctional anticancer agent that induces cancer cell apoptosis and stimulates cytokine synthesis by immune cells. Intravesical MCC is currently being evaluated in humans with high‐grade urinary bladder cancer. Evaluation of MCC in dogs with transitional cell carcinoma (TCC) will allow mechanistic studies in a natural animal model of TCC, and a potentially beneficial therapy for dogs with this cancer. In this study, we have determined the anticancer activity of MCC against canine TCC cells in vitro .
Methods: Canine TCC cells (K9TCC cell line) were incubated with MCC (0.05–100 μg/ml, 0.5–72 hours). Cellular proliferation was measured by MTT reduction. Cell cycle was analyzed by flow cytometry with propidium iodide. Apoptosis was identified by flow cytometry using anti‐active‐caspase‐3/PE and anti‐cleaved‐PARP/FITC antibodies. Apoptosis‐inducing activity of 100 μg/ml MCC in combination with piroxicam (0.1–1.0 uM) was evaluated.
Results: MCC inhibited K9TCC cell proliferation in a concentration‐dependent manner (maximal activity – 45% at 100 μg/ml MCC) in association with the presence of activated caspase‐3 and cleaved PARP. Inhibition of proliferation and apoptosis‐inducing activities of MCC were independent of cell cycle phase. A thirty‐minute exposure of MCC was sufficient for optimal activity. Piroxicam (0.5 uM) enhanced apoptosis‐inducing activity of MCC.
Conclusions: MCC induces apoptosis in K9TCC cells. This activity is potentiated by piroxicam. Following positive results in vitro , in vivo studies have been initiated. One dog, treated to date, has had a minor reduction in tumor volume following the first course of treatment with no treatment‐related toxicity. 相似文献
Methods: Canine TCC cells (K9TCC cell line) were incubated with MCC (0.05–100 μg/ml, 0.5–72 hours). Cellular proliferation was measured by MTT reduction. Cell cycle was analyzed by flow cytometry with propidium iodide. Apoptosis was identified by flow cytometry using anti‐active‐caspase‐3/PE and anti‐cleaved‐PARP/FITC antibodies. Apoptosis‐inducing activity of 100 μg/ml MCC in combination with piroxicam (0.1–1.0 uM) was evaluated.
Results: MCC inhibited K9TCC cell proliferation in a concentration‐dependent manner (maximal activity – 45% at 100 μg/ml MCC) in association with the presence of activated caspase‐3 and cleaved PARP. Inhibition of proliferation and apoptosis‐inducing activities of MCC were independent of cell cycle phase. A thirty‐minute exposure of MCC was sufficient for optimal activity. Piroxicam (0.5 uM) enhanced apoptosis‐inducing activity of MCC.
Conclusions: MCC induces apoptosis in K9TCC cells. This activity is potentiated by piroxicam. Following positive results in vitro , in vivo studies have been initiated. One dog, treated to date, has had a minor reduction in tumor volume following the first course of treatment with no treatment‐related toxicity. 相似文献
807.
808.
How to perform transvenous electrical cardioversion in horses with atrial fibrillation 总被引:1,自引:1,他引:1
M. Kimberly J. McGurrin DVM Dipl ACVIM Peter W. Physick-Sheard BVSc MSc FRCVS Daniel G. Kenney DVM Dipl ACVIM 《Journal of Veterinary Cardiology》2005,7(2):109
Electrical cardioversion of atrial fibrillation is a well-established technique for restoration of sinus rhythm in humans. While transthoracic cardioversion is more commonly used, transvenous electrical cardioversion (TVEC) has been reported as having higher efficacy at substantially lower energy levels. In horses, treatment of atrial fibrillation has essentially been limited to the administration of quinidine salts either orally or intravenously. TVEC provides an alternative to quinidine salts, especially for those animals in which quinidine is neither effective nor tolerated. The present report details this technique in horses, discusses possible complications of the procedure, and provides guidance for successful outcome. Still and video images are used to illustrate details with regard to TVEC techniques in horses. Please view supplemental material for the videos. 相似文献
809.
GAL‐ and VIP‐Immunoreactive Nerve Structures in the Ileum and Large Intestine of Pigs with Dysentery
W. Sienkiewicz J. Kaleczyc Z. Pidsudko M. Akomy 《Anatomia, histologia, embryologia》2005,34(Z1):47-47
The morphology, neurochemistry and function of intramural nerve structures in the mammalian gastrointestinal tract are relatively well known, but in normal, healthy individuals. The present study was aimed at investigating the chemical coding of nerve structures in the wall of the ileum and large intestine in normal pigs (n = 3) and in pigs undergoing dysentery (n = 6). Dysentery was evoked by artificial infection of the clinically healthy animals per os with Brachyspira hyodysenteriae. All the animals were deeply anaesthetized and transcardially perfused with 4% paraformaldehyde. The cryostat sections of the intestines were processed for double‐labelling immunohistochemistry using antisera against PGP 9.5, GAL and VIP. In the intramural plexuses of the control pigs, the percentage of GAL‐immunoreactive (GAL‐IR) perykarya varied from 11% (descending colon) to 19% (centrifugal turns of the ascending colon) whereas in the dysenteric pigs, it was distinctly higher, reaching from 28% (ileum) up to 48% (cecum). In the control animals, the percentage of VIP‐IR neuronal somata varied from 3% (descending colon) to 19% (ileum). In dysenteric pigs, it was from 6% (descending colon) up to 28% (cecum). In the muscular coat (MC) and mucous membrane (MM) of the normal intestine, very numerous GAL‐ and VIP‐IR nerve fibres were observed. The nerve fibres in the myenteric plexus (MP) were even more numerous than those in the muscular coat while in the outer (OSP) and inner (ISP) submucous plexuses, they were less abundant. In the dysenteric pigs, the nerve fibres found in MC, MP and OSP were less numerous, whereas those observed in ISP and MM were more abundant than those in the control animals. The present results suggest that GAL and VIP are involved in the regulation of inflammatory processes developing in the porcine gastrointestinal tract during dysentery. 相似文献
810.