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Primary Ciliary Dyskinesia in the Dog 总被引:1,自引:0,他引:1
Wallace B. Morrison DVM Norman J. Wilsman DVM PhD Leslie E. Fox DVM Cornelia E. Farnum DVM PhD 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1987,1(2):67-74
Electron microscopy was used to diagnose primary ciliary dyskinesia in a litter of English pointer dogs and in a golden retriever dog. A technique of membrane solubilization, fixation, and negative staining with glutaraldehyde tannic acid identified abnormally constructed central and B microtubules in respiratory cilia from dogs with primary ciliary dyskinesia. Shortened outer dynein arms commonly associated with primary ciliary dyskinesia actually represents the absence of a specific subset of the three most peripheral components of the whole outer dynein arm structure. 相似文献
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2005 Guidelines for the diagnosis, prevention and management of heartworm (Dirofilaria immitis) infection in dogs 总被引:2,自引:0,他引:2
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OBJECTIVE: (1) To determine whether an extracapsular patellar ligament/fascia lata graft would provide stability in the cranial cruciate ligament (CrCL)-deficient stifle comparable with that of the intact stifle. (2) To determine if different tibial anchor points would enhance stability of the CrCLdeficient stifle when compared with the standard fabellar-tibial suture (FTS) placement. STUDY DESIGN: Experimental. ANIMALS: Twenty-eight canine cadaver hind limbs. METHODS: Stifles were mounted in a jig and tested between loads of -65 and 80 N. After testing the intact CrCL, 4 stabilization techniques were tested after CrCL transection: lateral graft technique (LGT) and 3 FTS with different tibial anchor points. RESULTS: There were no significant differences in displacement between the LGT and standard FTS, between the LGT and the intact CrCL, or between the FTS and the intact CrCL, in either the Securos or the Screw-washer experiments. Stiffness of the intact CrCL was significantly greater than that of any stabilization technique and the cut CrCL. The standard FTS showed the least displacement of all suture stabilization techniques. Differences in stiffness were not significant between the suture stabilization techniques. CONCLUSIONS: Securely anchored, the LGT results in a reduction in drawer motion similar to that of the intact CrCL and the standard FTS. Altering the tibial anchor point for the FTS does not improve stiffness or enhance stabilization of the CrCL-deficient stifle. CLINICAL RELEVANCE: The LGT could be used for the treatment of CrCL ruptures in the dog. A clinical study is recommended. 相似文献
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Pastalkova E Serrano P Pinkhasova D Wallace E Fenton AA Sacktor TC 《Science (New York, N.Y.)》2006,313(5790):1141-1144
Analogous to learning and memory storage, long-term potentiation (LTP) is divided into induction and maintenance phases. Testing the hypothesis that the mechanism of LTP maintenance stores information requires reversing this mechanism in vivo and finding out whether long-term stored information is lost. This was not previously possible. Recently however, persistent phosphorylation by the atypical protein kinase C isoform, protein kinase Mzeta (PKMz), has been found to maintain late LTP in hippocampal slices. Here we show that a cell-permeable PKMz inhibitor, injected in the rat hippocampus, both reverses LTP maintenance in vivo and produces persistent loss of 1-day-old spatial information. Thus, the mechanism maintaining LTP sustains spatial memory. 相似文献
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Cells have developed ways to sense and control the size of their organelles. Size-sensing mechanisms range from direct measurements provided by dedicated reporters to indirect functional readouts, and they are used to modify organelle size under both normal and stress conditions. Organelle size can also be controlled in the absence of an identifiable size sensor. Studies on flagella have dissected principles of size sensing and control, and it will be exciting to see how these principles apply to other organelles. 相似文献
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Extract The recent interest in the control of salmonella infection in farm livestock by vaccination has been concerned principally with the disease in calves, pigs and poultry and with the use of living attenuated vaccines rather than vaccines using killed organisms. Ovine salmonellosis, perhaps because of its limited importance in countries other than New Zealand and Australia and the sporadic nature of outbreaks, has not figured prominently in the scientific literature. 相似文献