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101.
Veterinary surgeons today are performing increasingly complex and invasive feline surgical procedures. In light of this, it is crucial that perioperative pain management in these patients be a top priority. This article outlines pain physiology and pathophysiology, pain recognition and management strategies, relevant pharmacology, and techniques for local and regional analgesia in cats.  相似文献   
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The notion that a trade-off exists between immunity and reproduction is now a central concept in theories of sexual selection. However, whether such a trade-off exists between immunity and gamete viability has not been established. Here we show that genetic variance for high levels of an immune response required to fight bacterial infections is associated with genetic variance for low sperm viability. These data have implications for our understanding of sexual selection mechanisms and of reproductive costs in male longevity.  相似文献   
104.
Host-response patterns of intramammary infections in dairy cows   总被引:2,自引:0,他引:2  
Many different bacterial species have the ability to cause an infection of the bovine mammary gland and the host response to these infections is what we recognize as mastitis. In this review we evaluate the pathogen specific response to the three main bacterial species causing bovine mastitis: Escherichia coli, Streptococcus uberis and Staphylococcus aureus. In this paper we will review the bacterial growth patterns, host immune response and clinical response that results from the intramammary infections. Clear differences in bacterial growth pattern are shown between bacterial species. The dominant pattern in E. coli infections is a short duration high bacteria count infection, in S. aureus this is more commonly a persistent infection with relative low bacteria counts and in S. uberis a long duration high bacteria count infection is often observed. The host immune response differs significantly depending on the invading bacterial species. The underlying reasons for the differences and the resulting host response are described. Finally we discuss the clinical response pattern for each of the three bacterial species. The largest contrast is between E. coli and S. aureus where a larger proportion of E. coli infections cause potentially severe clinical symptoms, whereas the majority of S. aureus infections go clinically unnoticed. The relevance of fully understanding the bovine host response to intramammary infection is discussed, some major gaps in our knowledge are highlighted and directions for future research are indicated.  相似文献   
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Saturn's slow seasonal evolution was disrupted in 2010-2011 by the eruption of a bright storm in its northern spring hemisphere. Thermal infrared spectroscopy showed that within a month, the resulting planetary-scale disturbance had generated intense perturbations of atmospheric temperatures, winds, and composition between 20° and 50°N over an entire hemisphere (140,000 kilometers). The tropospheric storm cell produced effects that penetrated hundreds of kilometers into Saturn's stratosphere (to the 1-millibar region). Stratospheric subsidence at the edges of the disturbance produced "beacons" of infrared emission and longitudinal temperature contrasts of 16 kelvin. The disturbance substantially altered atmospheric circulation, transporting material vertically over great distances, modifying stratospheric zonal jets, exciting wave activity and turbulence, and generating a new cold anticyclonic oval in the center of the disturbance at 41°N.  相似文献   
107.
A phosphorus-31 nuclear magnetic resonance imaging technique has been used to obtain information on phosphorus metabolites from different spatial regions of tissues in vivo. The technique for selection of planes through the tissue is based on phase-encoding of spin echoes and was used to obtain one-dimensional discrimination of phosphorus-31 spectra from different parts of the tissue simultaneously. Specimens were resolved into 16 distinct slices and a signal-to-noise ratio of about 20 to 1 was obtained in 1/2 hour. Results are presented for phantoms, rat legs, and gerbil heads.  相似文献   
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