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1.
植物健康综合管理系统(IpHM)在保证根系健康生长方面确实起到了作用。这就对种植者提出了挑战。植物营养调节、水分管理、根/冠生长管理的成败取决于是否有健康的根系和成分配比适当的栽培基质。[编者按]  相似文献   
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植物健康综合管理系统(IpHM)在保证根系健康生长方面确实起到了作用。这就对种植者提出了挑战。植物营养调节、水分管理、根/冠生长管理的成败取决于是否有健康的根系和成分配比适当的栽培基质。[编者按]  相似文献   
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Large-amplitude electron density oscillations were observed on a Be(0001) surface by means of variable-temperature scanning tunneling microscopy. Fourier transforms of the images showed a ring of radius 2kF, where kF is the Fermi wave vector of the Be(0001) surface state. This wavelength was expected from Friedel oscillations caused by electronic screening of surface defects, but the amplitude of the waves for energies near the Fermi energy was anomalously large and inconsistent with the Friedel concept of screening. The enhanced amplitude of the waves must be a many-body effect, either in the electron gas (possibly an incipient charge density wave) or in the response of the lattice (electron-phonon coupling).  相似文献   
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Rats with mammillary body lesions produced with an angled approach do not show a "scalloping" in their behavioral records during fixedinterval reinforcement. Control experiments suggest that this effect was due to the electrode piercing the zona incerta, implicating the participation of extrapyramidal structures in timing behavior.  相似文献   
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The magnetic resonance (MR) imaging features, signalment, clinical history and outcome of 55 horses with a penetrating sole injury were evaluated. Our aim was to describe MR imaging findings within the hoof capsule, assess the utility of the technique and give recommendations for the optimal MR imaging protocol to evaluate such injuries. Data from five equine hospitals were analyzed retrospectively. The tract was more likely to be visualized in animals scanned within the first week postinjury. There was no significant predisposition based on breed, age, or gender. T2*W transverse sequences were the most useful for assessment of solar penetrations due to their orientation perpendicular to the deep digital flexor tendon, the reduced scanning time, and the T2* capability of enhancing magnetic susceptibility caused by hemorrhage.  相似文献   
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