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91.
Charlotte Erichsen DVM Mieth Berger RN Per Eksell DVM 《Veterinary radiology & ultrasound》2002,43(3):287-292
The aim of this study was to describe the scintigraphic appearance and location of the sacroiliac joint (SI-joint) in dorsal and dorso 30 degree lateral views of the equine pelvis in a scintigram. The pelvis from 10 different horses was prepared by attaching plastic tubes along relevant margins of the bone and around the SI-joint. A radioactive solution was injected into the tubes, and scintigraphic images were acquired with a gamma camera. Five specific landmarks were identified on the left and right sides of the pelvis. There was no significant difference in the distance measurements between the left and right sides in the dorsal view. The SI-joint was roughly ovoid in shape, with its long axis angled to the midline. The most craniolateral point of the SI-joint (Y) was located at the middle (SD = 0.04) of a line drawn from the caudal margin of the tuber sacrale (TS) to the craniolateral margin of the tuber coxa (TC), which was called TS-TC. In 85% of the specimens, the long axis of the SI-joint (SILA) was located caudal to or intersecting TS-TC, and the mean angle between SILA and TS-TC was 16.4 degrees (SD = 5.6 degrees). The distance from the caudomedial point of the SI-joint (Z) to Y was 0.38 times (SD = 0.04) the length of TS-TC. The distance from the tuber sacrale to the medial border of the SI-joint (TS-X) was 0.15 times (SD = 0.02) the length of TS-TC. In the oblique view, the SI-joint appeared wider and was positioned more laterally compared to the dorsal view. The distance TS-Y increased to 0.61 times (SD = 0.046) TS-TC, but SILA/TS-TC was essentially unchanged. The mean angle between TS-TC and SILA increased to 20.9 degrees (SD = 5.6 degrees). TS-X increased to 0.31 times (SD = 0.037) TS-TC. The location of the SI-joint was very similar in all horses, which makes it possible to estimate the location of the SI-joint in a scintigram in which the tuber sacrale and the craniolateral margin of the tuber coxa are identified. 相似文献
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93.
Summary Banana weevil (Cosmopolites sordidus Germar) is a major limiting factor in the cultivation of plantains and bananas (Musa spp. L.) in sub-Saharan Africa. The larvae damage the crop by tunneling in the corm. Chemical control is feasible but not sustainable, whereas host plant resistance is safe and has long term benefits. Banana weevil damage and infestation levels and corm hardness were assessed in Musa germplasm in order to determine the genetic control and potential mechanisms of resistance to this insect pest. Susceptibility/resistance to weevil was measured by the percentage coefficient of infestation (PCI) and damage in cross sections (CS) of the corm. All plantains were equally susceptible to the banana weevil, while a wild banana accession and some cooking and dessert banana cultivars showed high levels of resistance. Differential genotypic responses were observed in euploid plantain-banana hybrids. Segregation results suggest that host plant response to weevil in Musa is controlled by gene(s) exhibiting partial dominance towards the resistant parent and modifier genes with additive and dosage effects for susceptibility in the plantain parent. In natural banana germplasm, resistant clones showed increased corm hardness, as measured by a penetrometer in longitudinal and cross sections of outer and central corm tissues. This might suggest a non-preference mechanism for weevil resistance. However, the lack of correlation between corm hardness with PCI and CS scores in the segregating progenies suggested that other mechanisms may be more important in conferring resistance to banana weevil. 相似文献
94.
Objective To measure the plasma cortisol response in lambs castrated and docked by three different methods (ring castration and tail docking, ring and clamp castration and tail docking; ring and clamp castration and ring tail docking) for 4 h after treatment.
Design A physiological study with controls.
Procedure A rubber ring was applied to the scrotum. Then the castration clamp was placed, distal to the ring, on each spermatic cord such that there was no overlap of the crush lines.
Results There were no differences in the cortisol secretion of the lambs castrated and tail docked by the ring only and by the ring plus castration clamp methods. Using the castration clamp in addition to the ring on the tail had no effect on cortisol secretion.
Conclusions Using the castration clamp did not appear to reduce the cortisol response to ring castration and docking, as demonstrated elsewhere, because the areas of uncrushed tissue between the two castration clamp crush lines allowed nociception from ischemic scrotal tissue to be transmitted cranially via undamaged nerve fibers. 相似文献
Design A physiological study with controls.
Procedure A rubber ring was applied to the scrotum. Then the castration clamp was placed, distal to the ring, on each spermatic cord such that there was no overlap of the crush lines.
Results There were no differences in the cortisol secretion of the lambs castrated and tail docked by the ring only and by the ring plus castration clamp methods. Using the castration clamp in addition to the ring on the tail had no effect on cortisol secretion.
Conclusions Using the castration clamp did not appear to reduce the cortisol response to ring castration and docking, as demonstrated elsewhere, because the areas of uncrushed tissue between the two castration clamp crush lines allowed nociception from ischemic scrotal tissue to be transmitted cranially via undamaged nerve fibers. 相似文献
95.
RN McCARTHY LB JEFFCOTT JW FUNDER† M FULLERTON† IJ CLARKE† 《Australian veterinary journal》1991,68(11):359-361
A controlled period of submaximal exercise on a treadmill was used as a standardised stress test in 6 young horses to monitor the effects of training. Circulating plasma concentrations of immunoreactive beta-endorphin (IR beta-EP) were measured before, during and after the exercise period. The stress test was conducted on 3 occasions during an intensive training program lasting 14 weeks. In week 3 a marked increase in plasma IR beta-EP (P = 0.003) was demonstrated as a result of training, but by the last exercise test performed in week 9 no significant increase in plasma IR beta-EP concentrations could be detected. During the training period the basal concentrations of plasma IR beta-EP significantly decreased (P = 0.0059). Plasma adrenocorticotrophin (ACTH) did not increase during exercise, although there was a trend of decreasing basal plasma ACTH by the end of the training period. It was concluded that a standardised work test acted as a mild stress to unfit horses, but as the horses' fitness increased the hormonal response to exercise diminished. Basal plasma beta-EP concentrations were decreased with increasing fitness. 相似文献
96.
J.C. Zadoks 《EPPO Bulletin》1984,14(3):401-407
EPIPRE is an integrated pest and disease management system for wheat, fully computerized, based on on-line calculations of costs and benefits of pesticide treatments; it is field-specific and utilizes disease and pest monitoring in the field. The development of the project took five years (1977/1981). Cost effectiveness has been estimated in retrospect and in prospect using 1980 as a base year, covering the period 1977 through 1985. Future costs were disccrunted at a 10 % rate. The Net Present Worth of the project was estimated at nearly eight million Dutch guilders. The nonmeasurable effects of the project seem to be even more important than the measurable effect. 相似文献
97.
98.
99.
TP Rakitzis SA Kandel AJ Alexander ZH Kim RN Zare 《Science (New York, N.Y.)》1998,281(5381):1346-1349
Isolated diatomic molecules of iodine monochloride (ICl) were photodissociated by a beam of linearly polarized light, and the resulting ground-state Cl atom photofragments were detected by a method that is sensitive to the handedness (helicity) of the electronic angular momentum. It was found that this helicity oscillates between "topspin" and "backspin" as a function of the wavelength of the dissociating light. The helicity originates solely from the (de Broglie) matter-wave interference of multiple dissociating pathways of the electronic excited states of ICl. These measurements can be related to the identity and to the detailed shapes of the dissociating pathways, thus demonstrating that it is possible to probe repulsive states by spectroscopic means. 相似文献
100.
Coagulase-negative staphylococci (CNS) are isolated commonly from bovine milk and skin. Their impact on udder health and milk quality is debated. It has been suggested that sources and consequences of infection may differ between CNS species. Species-specific knowledge of the impact and epidemiology of CNS intramammary infections is necessary to evaluate whether species-specific infection control measures are feasible and economically justified. Accurate measurement of impact, sources, and transmission mechanisms requires accurate species level identification of CNS. Several phenotypic and genotypic methods for identification of CNS species are available. Many methods were developed for use in human medicine, and their ability to identify bovine CNS isolates varies. Typeability and accuracy of typing methods are affected by the distribution of CNS species and strains in different host species, and by the ability of test systems to incorporate information on new CNS species into their experimental design and reference database. Generally, typeability and accuracy of bovine CNS identification are higher for genotypic methods than for phenotypic methods. As reviewed in this paper, DNA sequence-based species identification of CNS is currently the most accurate species identification method available because it has the largest reference database, and because a universally meaningful quantitative measure of homology with known species is determined. Once sources, transmission mechanisms, and impact of different CNS species on cow health, productivity and milk quality have been identified through use of epidemiological data and accurate species identification methods, appropriate methods for routine use in research and diagnostic laboratories can be proposed. 相似文献