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101.
Todd C. Duffy DVM Rebecca Kirby DVM DACVIM DACVECC Elke Rudloff DVM DACVECC 《Journal of Veterinary Emergency and Critical Care》2004,14(2):84-99
Objective: To review the human and veterinary literature on the role of the vascular endothelial cell in health, as well as during hypoxic and inflammatory disease states. Data sources: Data from human and veterinary literature were reviewed through a Pubmed search and a manual search of the references listed in articles covering some aspect of vascular endothelial cell function. Human data synthesis: The development of techniques that allow the maintenance and growth of endothelial cells in culture has produced an explosion of new research in the area of endothelial cell physiology. This plethora of data has revealed the critical role that vascular endothelial cells play in both health and disease states. Interspecies variations can occur with respect to the vascular endothelial cell physiology and its response to pathologic conditions. Veterinary data synthesis: There is a paucity of information regarding the role of the vascular endothelial cell in health or disease of small animals. Many human studies use species cared for by veterinarians, providing information that may be applied to small animals and that may be used to construct future studies. Conclusion: An organ system itself, the vascular endothelium is an essential component of all organs in the body. The endothelial cell lining functions to maintain selective permeability between the blood and the tissue it supplies, regulate vascular tone, sustain blood fluidity through regulation of coagulation, and modulate interaction of leukocytes with the interstitium and inflammatory reactions. During disease states, the endothelial cell functions locally to limit the boundaries of the disease process. If these functions are not controlled, they can become a part of the pathogenic process, contributing to blood stasis and thrombosis, potentiation of local inflammation and interstitial edema formation, subsequent tissue hypoxia, and multiple organ dysfunction. Pharmacological investigations targeting the modulation of endothelial function during disease states have not yet advanced treatment protocols. Since all critically ill animals are at risk for some degree of endothelial cell dysfunction, treatment regimens should focus on promoting capillary blood flow and tissue oxygen delivery. 相似文献
102.
Background
The Agrobacterium vacuum (Bechtold et al 1993) and floral-dip (Clough and Bent 1998) are very efficient methods for generating transgenic Arabidopsis plants. These methods allow plant transformation without the need for tissue culture. Large volumes of bacterial cultures grown in liquid media are necessary for both of these transformation methods. This limits the number of transformations that can be done at a given time due to the need for expensive large shakers and limited space on them. Additionally, the bacterial colonies derived from solid media necessary for starting these liquid cultures often fail to grow in such large volumes. Therefore the optimum stage of plant material for transformation is often missed and new plant material needs to be grown. 相似文献103.
Gerhard Schröder Ewa Meinlschmidt Holger Bär Elke Bergmann Ingrid Pittorf 《Gesunde Pflanzen》2007,59(3):127-139
The competitive ability of maize is low in its early growth stages and because of this weed control is essential. Agricultural practice is dominated by chemical weed control. The trials indicated that some herbicide mixtures used at 75% of the permitted dose have herbicidal potential. In trials in the states Brandenburg, Sachsen, Sachsen-Anhalt and Thüringen, four herbicide mixtures were tested in the years 2004 to 2006.The practiced 75% of permitted dose and 50% of permitted doses were tested for their herbicidal potential. The weed species react differently to reduced herbicide doses. 50% of the 26 recorded weed species showed no drop in herbicide treatment efficacy at a reduced dose compared to the recommended dose. A drop in efficacy of between 1 and 5% was recorded after use of reduced herbicide rates in 25% of the other recorded weed species. 15?% of all recorded weed species showed a drop of efficacy of between 5 to 10%. Only 10% of recorded weed species reacted with an efficacy drop of more than 10?% between recommended and reduced doses. The tested herbicide mixtures had a different herbicidal potential for specific weed species. The herbicide treatment in maize is carried out after emergence of the weed species. It is therefore possible to choose the most suitable herbicide mixture at the 50% dose rate with the smallest drop of efficacy to target the specific species. In this way only slightly more weeds survive at a higher density compared with the recommended dose rate. The selection pressure is hardly higher. The knowledge of the herbicidal potential of mixtures could be used in agricultural practice. In this way the input of active ingredient/area can be reduced by the approximate efficacy of herbicide treatments. The tested herbicide mixtures are only an example of how, by the knowledge of efficacy reserves of herbicide in relation to the weeds present, the applied dose can be better adapted to the treatment frequency index. 相似文献
104.
Elke Krug 《Forest Pathology》1990,20(2):122-126
Dry pollen of Picea omorika was fumigated with 820 μg/m3 SO2 for 3 , 4 , or 5 days. Few or no adverse effects occurred during subsequent in vitro germination: germination percentage was not affected at all, and reduction of the pollen tube length was only 10% in pollen exposed for 5 days. Nevertheless pollination with fumigated pollen resulted in reduced seed production. 41% fewer seeds per cone were produced, and only 33% were filled seeds, compared to 70% filled seeds of the control. Seed-weight was reduced from 3.6 g per thousand in the control to 3.0 g per thousand, when cones were pollinated with pollen fumigated for 5 days. Similar but less striking effects were found with pollen fumigated for 3 or 4 days. 相似文献
105.
106.
TTA Rapid: Description of the Technique and Short Term Clinical Trial Results of the First 50 Cases 
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108.
109.
Vansnick E de Rijk P Vercammen F Rigouts L Portaels F Geysen D 《Veterinary microbiology》2007,122(1-2):166-171
Culturing of Mycobacterium avium subspecies paratuberculosis (Map) remains difficult and is time consuming. An alternative for the rapid detection of Map in samples is PCR. We have developed a sensitive DNA-extraction method based on sequence capture for the rapid detection of M. avium subspecies paratuberculosis by PCR in fecal and tissue samples. The method detected 10(2)Map/g feces using spiked samples, and reached a diagnostic sensitivity of 33,7% compared to 22% for culture. Analysis of tissue samples gave 65 polymerase chain reaction (PCR)-positive (42.2%) and 49 culture-positive samples (31.8%). Therefore, the detection limit of the DNA-extraction is the same as previously reported for culture, the PCR assay could detect more positive samples than the culture method. 相似文献
110.
In a field experiment, net nitrogen (N) mineralization and immobilization were studied in relation to: 1) population dynamics and activities of N-metabolizing soil microbial communities, 2) changes in substrate-induced respiration (SIR) and 3) potential urease acitvity. Nitrogen fertilization (80 kg NO3-N ha-1) without irrigation induced additional N mineralization up to 280 kg N ha-1. Net N-mineralization was weakly correlated to cell numbers of ammonifying and NH4+-oxidizing microorganisms. Potential urease activity, respiration activity, and substrate-induced respiration activity were not correlated with the amount of mineralized nitrogen. Irrigation significantly increased potential urease activity of the soil microflora. Substrate induced respiration activity and basal respiration activity of the soil microflora were highest in the unfertilized and non irrigated treatment. But greatest differences were detected between the two sampling dates. NO2--oxidizing and ammonifying microbial populations increased, while populations of NH4+-oxidizing and denitrifying microorganisms decreased with time. The results of this study demonstrate the interaction of nitrogen fertilizer application and irrigation on population dynamics of N-transforming soil microorganisms and microbial activities under field conditions. Detailed microbiological investigations of this type improve our understanding of nitrogen transformations in soil and suggest possible reasons of nitrogen losses, so that N fertilizer can be used more effectively and N losses be reduced. 相似文献