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Eva Patricia López‐Damián José Alfredo Jiménez‐Medina Miguel Angel Lammoglia Jaime Arturo Pimentel Lourdes Teresa Agredano‐Moreno Chris Wood Carlos Salvador Galina Tatiana Fiordelisio 《Anatomia, histologia, embryologia》2018,47(5):435-443
Embryo transfer using cryopreserved B. indicus embryos results in low pregnancy rates. The low viability of B. indicus embryos is likely a result of their low freezability relative to embryos from other species, notably B. taurus. Freezability is probably related to the quantity of lipid droplets in the embryonic cells. However, the mechanism underlying this association is unknown. Using multiphoton and transmission electron microscopy, the proportion, volume, morphology and composition of lipid droplets in fresh and cryopreserved B. indicus and B. taurus embryos were studied. B. indicus embryos have more droplets than B. taurus and a greater percentage of lipid droplets in clusters (34% vs. 24%; p < 0.05). Also, B. indicus individual droplets are of greater volume than those of B. taurus (47 μm3 vs. 34 μm3; p < 0.05). After freezing, the percentage of clusters decreased in B. indicus (11% vs. 5%; p < 0.05), while in B. taurus they increased (2% vs. 7%; p < 0.05). Freezing influenced the lipid droplet morphology, increasing the number of cracked droplets in B. indicus embryos (33% fresh vs. 62% frozen; p < 0.05), but not in B. taurus embryos (35% fresh vs. 34% frozen; ns). Regarding composition, saturated lipid droplets prevail in B. indicus embryos, contrary to B. taurus embryos. We observed differences in lipid droplet organization, proportion, volume, morphology and composition between B. indicus and B. taurus embryos which are altered in opposite directions following freezing. 相似文献
996.
A randomized,blinded, prospective clinical trial of postoperative rehabilitation in dogs after surgical decompression of acute thoracolumbar intervertebral disc herniation 下载免费PDF全文
997.
Predicting canopy macrolichen diversity and abundance within old-growth inland temperate rainforests
Windward slopes of the inland mountain ranges in British Columbia support a unique inland temperate rainforest (ITR) ecosystem. Increasing fragmentation and the loss of old ITR stands have highlighted the need for determining conservation biology priorities among remaining old forest stands. We have addressed this issue by surveying foliose macrolichens within 53 old ITR stands in British Columbia's 135,000 ha very wet-cool interior-cedar hemlock (ICHvk2) biogeoclimatic subzone in the upper Fraser River watershed. Study plots were stratified by leading tree species and by “wet” versus “dry” relative soil moisture conditions. Other plot variables included: temperature, precipitation, incident solar loading, and canopy openness. Ordination plots showed a distinct assemblage of foliose cyanolichens, including Lobaria pulmonaria, Lobaria retigera, Sticta fuliginosa, Nephroma isidiosum, Nephroma occultum, and Pseudocyphellaria anomala, whose abundance was correlated with increasing relative soil moisture, temperature, canopy openness, precipitation, and basal area of spruce. Logistic regression models similarly identified relative soil moisture and temperature in all parsimonious models. Leading tree species, in combination with “wet” relative soil moisture and/or temperature, were important factors explaining the presence or absence of five (Cavernularia hultenii, L. retigera, N. occultum, Platismatia norvegica, and Sticta oroborealis) of the eight modeled old-growth associate lichen species. This combination of conditions favouring the development of canopy lichen communities in old forests was best expressed in low elevation water receiving sites. We hypothesize that groundwater availability in these sites promotes species richness and abundance of canopy lichens by creating more favourable conditions for growth, and by reducing fire return intervals which allows for the accumulation of rare species over time. Historically, forests in these wet “toe-slope” positions were disproportionately targeted for logging. Their conservation should now be a high priority, given their disproportionate significance to maintaining canopy lichen diversity in the present-day landscapes. 相似文献
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Much has been written about a supposed shift ‘from government to governance’ in many policy areas, including forest policy. However, the idea remains very much at the level of hypothesis as few empirical studies have confirmed the transition. Part of the problem is the multi-dimensional character of governance itself, which includes traditional ‘government’ as one of many possible governance modes. By providing a three dimensional picture of these potential governance modes, including overlapping institutional, political and regulatory dimensions, this article analyses the complex and incomplete character of moves towards any new governance mode in a high-profile land use planning exercise in British Columbia, that of the “Great Bear Rainforest” protected area strategy on the province's mid-coast region in 2006. Little evidence of such a shift is uncovered, despite much rhetoric to the contrary. 相似文献
999.
Chris A. Preston BVSc MACVSc Kurt S. Schulz DVM MS Diplomate ACVS Philip B. Vasseur DVM Diplomate ACVS 《Veterinary surgery : VS》1999,28(5):341-347
OBJECTIVE: To determine the outcome of total hip arthroplasty in canine hindlimb amputees. STUDY DESIGN: Retrospective evaluation of clinical cases. METHODS: Data recorded from the medical records of nine dogs included patient signalment, indication for amputation and total hip arthroplasty (THA), interval between amputation and THA, and surgical complications. Radiographs were used to assess implant orientation and evidence of complications. Functional outcome was assessed using direct patient evaluation by one of the authors or primary surgeons, or through telephone interview between the primary author and the owner. RESULTS: Seven dogs ultimately had a good or excellent clinical results. Complications occurred in five dogs. Four dogs luxated the prosthetic joint without an obvious traumatic event within 9 weeks of the initial surgery. Revision surgeries resulted in successful coxofemoral reduction in three of four dogs. There were no clinical or radiographic findings suggestive of implant loosening or infection. CONCLUSION: THA can be a successful salvage procedure in the canine hindlimb amputee with disabling, non-neoplastic, noninfectious coxofemoral disease. The risk of luxation in the early postoperative period is high and revision surgery is required for stabilization. 相似文献
1000.
G Perkins D M Ainsworth H N Erb F Del Piero M Miller P A Wilkins J Palmer M Frazer 《Equine veterinary journal》1999,31(5):422-426
A retrospective multicentre study comparing historical, clinical, haematological, acid-base and biochemical findings of foals with Equine herpesvirus-1 (EHV-1) infection, septicaemia or prematurity was performed to determine if early diagnosis of EHV-1 foals was possible. Fifty-three foals were studied and were assigned to one of 2 groups: herpes positive (n = 14) or herpes negative (n = 39). The latter group included 20 septic, 11 premature, and 8 premature and septic foals. The presence of herpes antigen was confirmed by immunoperoxidase histochemical staining of tissues from necropsied foals. A nonparametric statistical analysis followed by a backwards elimination logistic regression was performed to establish a model at a P value of <0.05. All herpes positive foals died, while 47% (9/19) of the septic foals survived. Based upon our analysis, herpes positive foals were more likely to have total white blood cell counts less than 3 x 10(9)/l and to be icteric as compared to the septic and premature foals. Despite profound hepatic necrosis in the herpes positive foals, liver enzymes were not elevated and were not significantly different from the controls. 相似文献