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991.
Influence of temporary stockpiling on the initial development of restored topsoils Due to increasing construction and open‐cast mining activities on fertile agricultural land, excavation, stockpiling, and restoration of soils have become important issues in soil protection. In this study, we performed a restoration experiment to investigate how the conditions during stockpiling may influence initial soil development and plant growth on a restored site. Four topsoils, which originated from two depths (with uninhibited and inhibited aeration) of a nontrafficked and a trafficked topsoil deposit, were repacked in strips and sown with three meadow‐seed mixtures in strips perpendicular to the soil strips. During stockpiling as well as during the first 2 years after restoration, we assessed the physical and mechanical properties of the topsoils and (after restoration) also plant growth. None of the investigated properties of the topsoils was influenced by the depth in the deposit. In contrast, the coarse porosity and compression index were lower, whereas the bulk density and precompression stress were higher in the trafficked than in the nontrafficked topsoil deposit. However, these differences largely disappeared already in the course of soil restoration. Contrary to our expectations, the plants grew better on the soil of the trafficked topsoil deposit than on the soil of the nontrafficked topsoil deposit in the year of restoration. This might be attributed to the extremely dry and hot summer of that year. In the course of the 2 years following restoration, also the differences in plant growth tended to disappear. The remaining differences in bulk density and plant growth could not be attributed to differences in stockpiling conditions. The results suggest a re‐examination of current soil restoration guidelines. The maximum permitted stockpiling heights for topsoils might be increased in order to reduce the areas required for temporary stockpiling.  相似文献   
992.
云南松蠹害林分蠹害木清理技术   总被引:1,自引:0,他引:1  
根据多年的综合防治试验研究结果,提出了云南松蠹害林分蠹害木的清理技术。 包括:(1)蠹害林分受重程度划分;(2)蠹害木分级标准;(3)蠹害木的清理技术。阐明了蠹 害木清理的时间、次数、对象、顺序、方法及清理后的处理等技术措施。对于实施以 营林措施为基础的蠹害综合防治技术,有效地控制林间小蠹虫种群密度均具有重要作用。  相似文献   
993.
Abstract. The catchment simulated comprises 57 hectares of heavy clay soil managed as six arable fields. Mole and pipe drains carry surplus water into two ditches, one feeding into the other. Their combined flow was passed through a flume with an automatic water sampler, samples from which were analysed for nitrate. Measurements of nitrate concentration made during periods of water flow from 1990 to 1993 were simulated using a model comprising sub-models for leaching, mineralization, nitrogen uptake by crops and subsoil denitrification. The simulations were plotted against the measurements. For statistical evaluation, the correlation coefficient was used to assess the degree of association between the measurements and the simulations and the mean difference to assess the agreement. The correlation between the simulations and the measurements was significant in two of the three seasons, but the mean difference was significant in all three. However, taking all three seasons together gave a very highly significant correlation and a non-significant mean difference.  相似文献   
994.
A report of a cat with a true diaphragmatic hernia in which only falciform fat had herniated is pressented. The lession was misinterpreted as a pulmonary mass. Additional radiographic studies which may have been of diagnostic benefit are briefly discussed.  相似文献   
995.
LATERAL COLLATERAL LIGAMENT AVULSION OF THE HUMERORADIAL JOINT IN A HORSE   总被引:1,自引:0,他引:1  
This report describes traumatic avulsion of the lateral collateral ligament of the humeroradial joint in a horse. The history and diagnostic procedures are included with relevant radiographs and ultrasonographs. The poor prognosis associated with this injury is due to degenerative joint disease.  相似文献   
996.
997.
The effect of age on susceptibility of young pigs to streptococcic lymphadenitis was investigated. Twenty-nine cesarean-derived, colostrum-deprived pigs were allotted to 7 groups exposed to type IV group E Streptococcus (GES) at 5, 14, 28, 35, 56, 70, and 84 days of age. Four cesarean-derived, colostrum-deprived pigs were maintained as nonexposed controls. Six naturally farrowed, susceptible controls were exposed to GES at 63 to 84 days of age. All exposed pigs were killed and necropsied 28 days after exposure. Lesions of streptococcic lymphadenitis were not observed in pigs exposed at 5 or 14 days of age, except for 1 microabscess in a mandibular lymph node in a pig exposed at 14 days, but GES was recovered from 11% of lymph nodes examined from pigs of those age groups. Lesions and GES-positive lymph nodes were frequent in cesarean-derived, colostrum-deprived pigs exposed at 28 days and older and in susceptible controls. Serologic response to exposure, as determined by microtitration agglutination test and bactericidal test, was observed only in pigs exposed at 14 days and older. The absence of abscess development in pigs exposed at 5 or 14 days of age was not caused by antibody or failure of infecting organisms to reach the target organs.  相似文献   
998.
Cervical vertebral fusion was noted radiographically in four dogs presented for signs of cervical spinal cord compression. Ventral extradural spinal cord compression was seen on myelography at intervertebral disc spaces adjacent to the fused vertebrae in two dogs and at a site removed in two dogs. At surgery, no intervertebral disc space was found in the area of fusion. No other instances of cervical vertebral fusion were identified in reviewing radiographs of 1225 other dogs with cervical intervertebral disc extrusion evaluated at our hospital. Clinical signs resolved in all dogs after surgical removal of extruded intervertebral disc material. Information from these four dogs suggest vertebral fusion may predispose adjacent discs to herniation.  相似文献   
999.
Palpation of the testicles and epididymides was used to determine the prevalence of ram epididymitis (RE) in Utah range flocks over a 5-year period. Of 62 range flocks examined, 58 had rams with palpable lesions. A comparison was made of prevalence by right vs left testicle involvement, but no significant difference was found. Culling all rams with palpable lesions from the flock progressively reduced the annual incidence, but did not eliminate RE from any flock. Semen and specimens of reproductive tract tissue were obtained from representative flocks for bacterial culture. Brucella ovis was found commonly in range flocks, but was not isolated from RE-affected rams in virgin, ram-producing flocks. In the ram-producing flocks, a gram-negative, pleomorphic rod-type organism was found. It was concluded that RE should be considered as 2 disease entities, based on the finding of 2 causative organisms and the management systems under which those organisms are found. Brucella ovis was the major cause in persistently infected range flocks, whereas the gram-negative pleomorphic rod-type organism is the apparent cause of RE in virgin, ram-producing flocks.  相似文献   
1000.
Insulinoma and Subclinical Peripheral Neuropathy in Two Dogs   总被引:1,自引:0,他引:1  
Two dogs with diffuse, subclinical polyneuropathy associated with insulinoma are reported. Seizures were the dominant sign of central nervous system disease. One dog had clinical signs of facial nerve paralysis. Lesions in selected appendicular and cranial nerves included a mixture of demyelination, remyelination, and axonal degeneration. The incidence (range: 18-47%) of these changes far exceeded that of comparable nerves from six control dogs (range 0-11%). Myopathic and electrodiagnostic findings were compatible with the nerve changes.  相似文献   
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