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121.
青海省海南州高寒草地荒漠化治理技术与对策   总被引:3,自引:1,他引:3  
总结了海南州高寒干旱草地荒漠化特征和成因,分析出气候变化、毁草开荒、超载过牧、鼠类危害、利用不当、执法不严等是草地荒漠化的主要原因,通过对荒漠化草地实行人工补播优良牧草、灭除毒草、消灭鼠害、禁牧封育、暖棚养畜、营造饲料护牧林等措施,提出了防止草地荒漠化的对策及治理技术.  相似文献   
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An extensive field comparison of the gamma interferon (IFN-gamma) assay and the single intradermal tuberculin test for the diagnosis of bovine tuberculosis was conducted in Australia. The specificity of the IFN-gamma assay was determined by testing more than 6000 cattle from tuberculosis-free herds and varied from 96.2% to 98.1%, depending on the cut-off point chosen to define a positive reactor. For the sensitivity trial, cattle from herds being de-populated because of bovine tuberculosis were examined with both assays. The sensitivity of the IFN-gamma assay was shown to be significantly higher than the single intradermal tuberculin test and varied from 76.8% to 93.6% depending on the method of interpretation. A maximum overall sensitivity of 95.2% was obtained by testing with the IFN-gamma and the tuberculin test in parallel. The superior sensitivity of the IFN-gamma assay and the ability to adjust the sensitivity of the system depending on the task involved, will provide the Australian Tuberculosis Eradication Campaign with a valuable additional test to enable it to accomplish its goals.  相似文献   
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Objective — To determine the minimum alveolar concentration (MAC) of desflurane (DES) in the horse.
Study Design — Prospective study.
Animals — Six healthy adult horses (three males and three females) weighing 370 ±16 kg and aged 9 ±2 years old.
Methods — Anesthesia was induced with DES vaporized in oxygen via a face mask connected to a large-animal, semiclosed anesthetic circle system. The horses were endotracheally intubated and positioned in right lateral recumbency. Inspired and end-tidal DES were monitored using a calibrated Ohmeda RGM 5250 multigas analyzer (Ohmeda-BOC, Spain). The MAC of desflurane that prevented gross purposeful movement in response to 60 seconds of noxious electrical stimulation of oral mucous membranes was determined.
Results — The time from the start of DES administration to lateral recumbency was 6.1 ±0.9 min. The MAC of DES in these horses was 7.6 ±0.4%. Time required for the animal to regain sternal recumbency after 98 ±4 minutes of anesthesia was 6.6 ±0.5 minutes and the time to standing was 14.3 ±2.7 minutes.
Conclusions — The MAC of desflurane in these horses was 7.6 ±0.4%. DES provided a rapid induction to, and recovery from, anesthesia.
Clinical Relevance — Desflurane offers the potential for more precise control during anesthesia, and may allow a faster and uneventful recovery. It is important to know the MAC of an inhalant to use it clinically.  相似文献   
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The high molecular weight glutenin subunits (HMW-GS) play a key role in end-use quality of wheat. Their particular primary structure is mostly derived from DNA sequencing, which gives no information on potential post-translational modifications. This paper reveals the primary structure of HMW-GS 1Dx2 by proteomic analysis. For this purpose, HMW-GS were first isolated from wheat flour (cv. Contra). The relative molecular mass (Mr) of subunit 1Dx2 present in the HMW-GS mixture was then very accurately determined with high-performance liquid chromatography–electrospray ionization-mass spectrometry using a quadrupole-time-of-flight mass analyzer (HPLC–ESI-QTOF-MS). The obtained Mr value (87,105) differed from the value derived from its protein sequence in the NCBI database (87,007). The subunit was further purified by preparative reversed-phase HPLC and partially hydrolyzed with chymotrypsin. The resulting 1Dx2 peptides were then analyzed by HPLC–ESI-MS/MS and the MS data were compared to amino acid sequences in protein databases. The discrepancy between the calculated and the measured Mr of 1Dx2 was explained by a missing proline in the 1Dx2 amino acid sequence from the database and not by any post-translational glycosylation.  相似文献   
129.
Soft x-ray contact microscopy, utilizing single-shot exposures of approximately 60 nanoseconds duration in polymethyl methacrylate, has been realized with a resolution of 300 angstroms. The radiation spectrum is intense in the "window" between 23 and 44 angstroms where water is transparent compared to biological materials, and therefore permits viewing of wet samples.  相似文献   
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Abstract

AIMS

To determine the frequency of the FAS-ligand gene (FASLG) variant associated with feline autoimmune lymphoproliferative syndrome (FALPS) and the proportion of carriers of the variant in three British shorthair (BSH) breeding catteries in New Zealand.  相似文献   
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