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371.
Flam F 《Science (New York, N.Y.)》1992,258(5087):1428-1429
372.
Flam F 《Science (New York, N.Y.)》1992,258(5087):1441
373.
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375.
The death of a 6-week-old alpaca being treated for acute polyarthritis is described. Post-mortem and histological findings included fibrinous mural endocarditis, lung abscessation, acute passive congestion of the liver, embolic suppurative nephritis and chronic nonsuppurative polyarthritis. Actinobacillus suis was isolated from the heart lesion and in pharyngeal swabs from four of six clinically normal alpacas in the same flock. 相似文献
376.
Twenty-eight varieties of commercially-available cat food (23 canned, 5 dried) were analysed for iodine. The iodine concentration varied from less than 0.37 micromol/kg to 41.8 pmol/kg, wet weight (less than 1.48 micromol/kg to 167 micromol/kg, dry weight). Excessive or insufficient iodine intake or wide swings in iodine intake over prolonged periods may contribute to thyroid disorders in cats. 相似文献
377.
Pollard JC Littlejohn RP Johnstone P Laas FJ Corson ID Suttie JM 《New Zealand veterinary journal》1992,40(2):56-61
Heart rate and behaviour during and following velvet antler removal were monitored in yearling red deer stags to determine the extent to which this procedure was perceived by the deer to be aversive. Nine stags normally kept at pasture were habituated over 5 weeks to the following daily handling procedure. Each deer was fitted with a harness containing a heart rate monitor. It was then allowed to run through a fixed course in a deer yard, restrained for 40 s in a mechanical deer crush, and then confined for 3.5 h with the remainder of the group of stags in an indoor pen containing food and water. In Week 6, the deer were subjected to either restraint for 6 minutes (the control treatment) or removal of one velvet antler under local anaesthesia. Each velvet antler was removed on separate occasions, either on Days 1 and 2 (five deer) or Days 3 and 4 (four deer). The control treatment was applied to all deer when velvet antler was not being removed, and on Day 5. Heart rate and behaviour (time taken to enter the treatment area, and number of struggles made during restraint) were measured before and during treatment, and post-treatment activities were recorded at 0, 1 and 3 h (indoors), and at 6 and 9 h (at pasture). Heart rate was higher during the second velvet antler removal treatment than during the first, but lower during the second control treatment than the first (P<0.05). During velvet antler removal, stags struggled more, and after the treatment flicked their ears, shook their heads, and groomed themselves more than control stags (P<0.05). Stags whose velvet antler had been removed spent less time eating than control stags, and spent progressively more time sitting during the 3.5 h of confinement (P<0.05). However, during the paddock observation at 9 h post-treatment, stags which had had their velvet antler removed grazed more than control stags (P<0.05). The increase in heart rate over the two velvet antler removal treatments and the greater amount of struggling during velvet antler removal indicated that it was more aversive than the control treatment. Post-treatment differences in behaviour may have been due to pain following velvet antler removal. 相似文献
378.
Williams TD Rebar AH Teclaw RF Yoos PE 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1992,21(4):106-110
Hematologic and/or serum chemical analyses were done on a total of 27 non-tranquilized adult and juvenile wild sea otters, 66 tranquilized adult and juvenile wild sea otters, and 26 wild sea otter pups. The median and inner 90 percentile range were determined for the adult, juvenile, and pup groups and for the following subgroups: adult male versus adult female, juvenile male versus juvenile female, pup male versus pup female, captured with dip net versus captured with Wilson trap, and tranquilized adults and juveniles versus non-tranquilized adults and juveniles. When values for adults were compared to values for juveniles and pups, hematocrits, red blood cell counts, and hemoglobin levels were significantly lower in pups. This is consistent with documented findings in other species. White cell counts were also somewhat lower in younger animals. Among the subgroups, significantly higher hemoglobin levels, white cell counts and neutrophil counts were found in adult females than in adult males. This is in direct contrast to what is seen in other mammalian species and warrants further documentation. Method of capture and tranquilization did not appear to influence either hematologic or serum biochemical determinations from a clinical perspective. 相似文献
379.
In the present study a cytological, histological and morphometrical comparison between the ovaries of the llama, the cow and the sheep is presented, at two phases of the ovarian cycle. There were found differences in the amount of primordial and primary follicles, the size of secondary follicles and follicular cells, and type and distribution of the connective tissue inside the stroma of the ovary. It would be necessary to study the fine structure of the ovary and the so-called "embryological remnants", for its permanent appearance in most (50%) of the ovaries. 相似文献
380.
A. Schots J. De Boer A. Schouten J. Roosien J. F. Zil Verentant H. Pomp L. Bouwman-Smits H. Overmars F. J. Gommers B. Visser W. J. Stiekema J. Bakker 《European journal of plant pathology / European Foundation for Plant Pathology》1992,98(2):183-191
Engineering resistance against various diseases and pests is hampered by the lack of suitable genes. To overcome this problem we started a research program aimed at obtaining resistance by transfecting plants with genes encoding monoclonal antibodies against pathogen specific proteins. The idea is that monoclonal antibodies will inhibit the biological activity of molecules that are essential for the pathogenesis. Potato cyst nematodes are chosen as a model and it is thought that monoclonal antibodies are able to block the function of the saliva proteins of this parasite. These proteins are, among others, responsible for the induction of multinucleate transfer cells upon which the nematode feeds. It is well documented that the ability of antibodies to bind molecules is sufficient to inactivate the function of an antigen and in view of the potential of animals to synthesize antibodies to almost any molecular structure, this strategy should be feasible for a wide range of diseases and pests.Antibodies have several desirable features with regard to protein engineering. The antibody (IgG) is a Y-shaped molecule, in which the domains forming the tips of the arms bind to antigen and those forming the stem are responsible for triggering effector functions (Fc fragments) that eliminate the antigen from the animal. Domains carrying the antigen-binding loops (Fv and Fab fragments) can be used separately from the Fc fragments without loss of affinity. The antigen-binding domains can also be endowed with new properties by fusing them to toxins or enzymes. Antibody engineering is also facilitated by the Polymerase Chain Reaction (PCR). A systematic comparison of the nucleotide sequence of more than 100 antibodies revealed that not only the 3′-ends, but also the 5′-ends of the antibody genes are relatively conserved. We were able to design a small set of primers with restriction sites for forced cloning, which allowed the amplification of genes encoding antibodies specific for the saliva proteins ofGlobodera rostochiensis. Complete heavy and light chain genes as well as single chain Fv fragments (scFv), in which the variable parts of the light (VL) and heavy chain (VH) are linked by a peptide, will be transferred to potato plants. A major challenge will be to establish a correct expression of the antibody genes with regard to three dimensional folding, assembly and intracellular location. 相似文献