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1.
Prophylactic efficacy of tilmicosin for bovine respiratory tract disease   总被引:3,自引:0,他引:3  
The prophylactic administration of injectable tilmicosin for pneumonia in weaned beef calves was investigated in 1,806 animals. Comparisons were made among calves receiving an "on-arrival" injection of tilmicosin, calves receiving a single injection of long-acting oxytetracycline, and calves receiving no prophylaxis. Morbidity and mortality attributable to pneumonia, morbidity and mortality attributable to all causes, and case fatality were significantly lower in the group of calves that received tilmicosin, compared with calves that received long-acting oxytetracycline and calves that received no prophylactic antibiotic. Mean time to initial pneumonia treatment was significantly extended in calves that received prophylaxis, compared with those that received no antibiotic on arrival at the feedlot. Calves that received tilmicosin gained significantly more weight than calves that received oxytetracycline. Calves that were not treated for pneumonia during the trial period gained significantly more weight than did those calves that were treated for pneumonia regardless of experimental group. The majority of mortalities were attributable to fibrinous pneumonia (31/34). Important bacterial isolates (Pasteurella spp, Haemophilus somnus, Actinomyces pyogenes) obtained at necropsy did not have resistance to tilmicosin in association with administration of tilmicosin as prophylaxis for pneumonia. However, bacterial resistance to trimethoprim/sulfonamide and to oxytetracycline were commonly found in these postmortem isolates.  相似文献   
2.
Rat adrenal cortex contains a protein(s) that binds pregnenolone with high affinity. This binding, demonstrated by gel filtration and by a dextran-coated charcoal method, was associated with the cytosol and with fractions solubilized by sonication from the mitochondria and microsomes. The binding of pregnenolone was saturable and was inhibited by mercurials and proteolytic enzymes. Pregnenolone-binding was not influenced by the presence of progesterone, deoxycorticosterone, corticosterone or aldosterone, but was inhibited by steroids with a 3beta-hydroxy-5-ene structure similar to pregnenolone, and by hydroxymethylene steroid and cyanoketone. We suggest that this protein is involved in the intracellular transport and retention of pregnenolone within adrenal cortical cells.  相似文献   
3.
Cognitive accounts of panic predict that panic disorder patients will be particularly prone to misinterpret autonomic sensations. Several studies have produced results consistent with this prediction, but each is open to alternative interpretation. To clarify matters, 2 studies administered the Body Sensations Interpretation Questionnaire (BSIQ) to panic patients and controls. Panic patients were more likely to interpret ambiguous autonomic sensations as signs of immediately impending physical or mental disaster and were more likely than other anxiety disorder patients and nonpatients to believe these interpretations. In a 3rd study, a brief version of the BSIQ was shown to have satisfactory test-retest reliability, to change with treatment, and to discriminate treatments that varied in their effects on panic.  相似文献   
4.
以枸杞鲜叶为原料,在杀青工序前增加室温自然摊放萎凋工序,可明显减轻枸杞叶茶的青腥味,增加枸杞叶中的可溶性糖、游离氨基酸和水浸出物含量,改进枸杞叶茶汤的滋味和香气,提高枸杞叶茶品质;但萎凋也降低了枸杞叶中的类黄酮、多酚和VC等活性成分的含量.试验结果表明枸杞叶的最适萎凋时间为7 h.  相似文献   
5.
丹江口水库汉江干流库区淤积分析   总被引:2,自引:0,他引:2  
丹江口水库建成后,改变了天然河道的水沙输移条件,入库水沙受人工调度控制,进入了水库淤积重新造床过程,自建库至 2003 年,入库沙量 98 %以上都淤积在库内,其中有 85 %的淤积量都分布在干流库区内 , 出库的泥沙也都是异重流冲泻质。根据丹江口水库历史及近期资料,对汉江干流库区纵、横、垂 3 个方向的淤积分布进行了详细的分析研究,为三峡水库的运用提供良好的借鉴。  相似文献   
6.
Circulatory changes following standardized compression trauma to the hind leg in dogs were evaluated using an electromagnetic flow meter and repeated angiography. A transient increase of flow to the injured limb and within the traumatized region was observed. Good agreement was found between the electromagnetic flow recordings and estimates of relative changes in flow by the angiographic method.  相似文献   
7.
Aspiration of hydrochloric acid in rabbits resulted in an increased P(A-a)O2 together with increases in both lung water volume and lung extravascular albumin. This finding suggests lung damage following acid aspiration is related to changes in capillary permeability, with pulmonary edema resulting from the movement of albumin and water into the interstitial space. Therapy with albumin and furosemide together reduced the lung water and albumin accumulation and decreased P(A-a)O2. Treatment with albumin or furosemide alone was ineffective. Caution should be exercised in administering albumin alone for therapy of pulmonary edema when plasma protein is not clearly decreased, or when increased pulmonary capillary permeability is suspected.  相似文献   
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9.
The objective of the study was to evaluate the walking ability and the energy cost of walking in patients before and after total hip replacement. The oxygen intake and the maximum walking speed were measured immediately before and 6 months after operation in 25 patients. Although the oxygen intake did not change significantly in most patients it was decreased in those patients who before surgery had had the worst walking capacity. The average maximum walking speed almost doubled in the 25 patients.  相似文献   
10.
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