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排序方式: 共有235条查询结果,搜索用时 31 毫秒
161.
Christopher A. Adin DVM Clare R. Gregory DVM Diplomate ACVS rew E. Kyles BVSC PhD Diplomate ACVS Larry Cowgill DVM PhD Diplomate ACVIM 《Veterinary surgery : VS》2001,30(6):515-521
OBJECTIVE: To identify preoperative diagnostic results that predict postoperative complications and survival in feline renal-transplant recipients. STUDY DESIGN: Retrospective clinical study. ANIMALS: Sixty-one feline renal allograft recipients. METHODS: Medical records for 61 consecutive cats that underwent renal allograft transplantation between January 1, 1996, and December 1, 1999, were reviewed. Age, diagnosis, body weight, body condition score, preoperative medical treatment, systolic blood pressure, packed cell volume, biochemical parameters at admission and at the time of surgery, postoperative complications, and postoperative survival were recorded. Associations of preoperative data with the occurrence of postoperative complications were determined using logistic regression. Postoperative survival was graphed using a Kaplan-Meier cumulative-survival plot. Associations of covariates with postoperative survival were analyzed using Cox proportional hazards analysis. RESULTS: Two parameters were significantly associated with occurrence of postoperative central nervous system (CNS) disorders: blood urea nitrogen concentration (odds ratio = 1.083; 95% CI = 1.018 to 1.148) and serum creatinine concentration (odds ratio = 1.8; 95% CI = 1.413 to 2.187) at the time of surgery. Postoperative survival 6 months after transplantation was 59%, though 3-year survival remained at 42%. Of all covariates investigated, only recipient age (relative hazard = 1.183; 95% CI = 1.039 to 1.334) was significantly associated with survival. CONCLUSION AND CLINICAL RELEVANCE: Standard measures of preoperative renal dysfunction do not predict postoperative survival in cats after renal transplantation, although an increase in the degree of preoperative azotemia is associated with an increased risk of CNS disorders after surgery. Increased recipient age is associated with decreased survival after renal transplantation. 相似文献
162.
The aim of this study was to determine the amounts of water-soluble carbohydrate (WSC), WSC constituents and protein leached from a range of U.K. hays soaked according to common practice. Initial hay WSC content ranged from 123 to 230 g/kg dry matter (DM). Soaking the hays for up to 16 hours in water at a mean temperature of 8°C resulted in a mean loss of 27 per cent (range 6 to 54 per cent) of hay WSC. The mean percentage losses of WSC constituents were 24 per cent (range 14 to 31) for fructan, 41 per cent (range 21 to 70) for fructose, 45 per cent (range 28 to 100) for sucrose and 56 per cent (range 29 to 100) for glucose. The mean crude protein content of the initial hays was 58.7 g/kg DM (range 30 to 86 g/kg DM) and this value was not affected significantly by soaking. Despite a mean WSC loss of 27 per cent, the WSC contents of seven of the hays remained above the suggested upper limit for laminitic animals of 100 g/kg DM. 相似文献
163.
In England Pulsatilla vulgaris is a threatened herb that declined from 130 to 33 sites between 1750 and the 1960s due to ploughing-up of calcareous grassland. We examined the subsequent fate of these populations using documentary evidence and field survey. Demographic trends were related to changes in grassland composition, structure and management and responses to increased above-ground competition (caused by reduced grazing) were simulated in a 10-year shading experiment. Since 1968 P. vulgaris has been lost from 16 sites and gradually declined on four others. However, the total population size increased by 258% due to the reintroduction of winter grazing on three sites. This produced a significantly shorter, more herb-rich sward, with a lower cover of Bromopsis erecta (c. 10%), than on sites where populations remained stable or declined. Experimental shading had a significant negative effect on plant survival and flowering performance. These results confirmed that reduced grazing is now one of the major threats to species dependent on short swards, especially on isolated sites where livestock farming is no longer economically viable. That many of these declines took place on nature reserves highlights the difficulties of managing isolated grasslands, and the urgent need to re-instate grazing on reserves supporting populations of threatened species in otherwise intensively managed lowland landscapes. 相似文献
164.
Sofie F. Bhatti An E. Vanhaesebrouck Iris Van Soens Valentine A. Martlé Ingeborgh E. Polis Clare Rusbridge Luc M. Van Ham 《Veterinary journal (London, England : 1997)》2011,189(3):284-288
The clinical and clinicopathological characteristics, treatment and outcome of vermicular muscle contractions (myokymia) and generalized muscle stiffness (neuromyotonia) in 37 Jack Russell terriers were evaluated retrospectively. Thirty dogs were affected by both disorders, whereas seven were presented with myokymia and never developed neuromyotonia. Clinical signs started at the mean age of 8 months. Except for signs of myokymia and neuromyotonia, clinical and neurological examination was normal in all dogs. Thirty dogs demonstrated typical signs of hereditary ataxia.Changes in serum chemistry included increased creatine kinase, aspartate aminotransferase and alanine aminotransferase concentrations. Electromyographic abnormalities, especially in muscles showing macroscopically visible myokymia, consisted of semirhythmic bursts of doublet, triplet, or multiplet discharges of a single motor unit. The amplitudes varied between 80 μV and 1 mV and occurred with an interburst frequency between 10 and 40 Hz and an intraburst frequency between 150 and 280 Hz.Most dogs were treated with a sodium channel blocker with variable results. Seven dogs died (most likely because of hyperthermia) or were euthanased during a neuromyotonic attack; 15 dogs were euthanased due to worsening of clinical signs, or lack of or no long-lasting effect of medication, and three were euthanased for unknown or unrelated reasons. Nine dogs were lost to follow-up and three were still alive 5–10.5 years after the start of clinical signs. In conclusion, young Jack Russell terriers with myokymia and neuromyotonia should undergo a complete blood and electrophysiological examination. Long-term prognosis is not favourable. 相似文献
165.
Jing Wang Chongnan Wang Yan Long Clare Hopkins Smita Kurup Kede Liu Graham J King Jinling Meng 《Plant methods》2011,7(1):1-7
Background
Protein extraction is a frequent procedure in biological research. For preparation of plant cell extracts, plant materials usually have to be ground and homogenized to physically break the robust cell wall, but this step is laborious and time-consuming when a large number of samples are handled at once.Results
We developed a chemical method for lysing Arabidopsis cells without grinding. In this method, plants are boiled for just 10 minutes in a solution containing a Ca2+ chelator and detergent. Cell extracts prepared by this method were suitable for SDS-PAGE and immunoblot analysis. This method was also applicable to genomic DNA extraction for PCR analysis. Our method was applied to many other plant species, and worked well for some of them.Conclusions
Our method is rapid and economical, and allows many samples to be prepared simultaneously for protein analysis. Our method is useful not only for Arabidopsis research but also research on certain other species. 相似文献166.
167.
168.
Bøgh KL Barkholt V Rigby NM Mills EN Madsen CB 《Journal of agricultural and food chemistry》2012,60(11):2934-2942
The major peanut allergen Ara h 1 is an easily digestible protein under physiological conditions. The present study revealed that pepsin digestion products of Ara h 1 retained the sensitizing potential in a Brown Norway rat model, while this sensitizing capacity was lost by separating the digest into fractions by gel permeation chromatography. Protein chemical analysis showed that the peptide composition as well as the aggregation profiles of the fractions of Ara h 1 digest differed from that of the whole pool. These results indicate that the sensitizing capacity of digested Ara h 1 is a consequence of the peptides being in an aggregated state resembling the intact molecule or that most peptides of the digests need to be present in the same solution, having a synergistic or adjuvant effect and thereby augmenting the immune response against other peptides. 相似文献
169.
The Mediterranean fruit fly Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) (medfly) is a polyphagous pest of global economic importance. This study tested the suitability of two different adhesive powders, EntostatTM and an adhesive metal powder, as insecticide carriers for use in a lure and kill pest control system, that would allow the auto-dissemination of insecticide from males to female conspecifics through sexual interactions. Lethal time to 50 % (LT50) irreversible knockdown was calculated for male and female medfly artificially contaminated by five different doses of spinosad insecticide, formulated with each adhesive carrier powder. The formulations with adhesive metal powder resulted in a rapid knockdown of medfly which was too fast for use in an auto-dissemination system. Entostat powder with 2 % spinosad gave the best performance, allowing sufficient time for transfer between conspecifics before knockdown and, therefore, allowing the most auto-dissemination (LT50 4 h). Knockdown through transfer of powder from males to females during mating was confirmed, with knockdown at 70–78 % for mated females, with a LT50 of <40 h. These results indicate that Entostat powder is a suitable carrier powder for the development of an insecticidal auto-dissemination control system. 相似文献
170.