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161.
Extracorporeal shock wave therapy (ESWT) is an accepted form of treatment for chronic cases of proximal suspensory desmitis (PSD). Subjective evaluation of horses shortly after being treated with ESWT has led clinicians to comment on an immediate reduction in lameness. This study aimed to evaluate the analgesic effect of ESWT on 16 horses with PSD or PSD-like pain in a fore- or hindlimb. To objectively assess lameness, gait analysis was performed on an instrumented treadmill before and 6, 24, 48 and 72h after ESWT of the origin of the suspensory ligament and the results compared to the effects of local anaesthesia. Stride frequency, stance duration, vertical impulse and peak vertical force were determined. Thermographic imaging and evaluation of skin sensitivity of the treated area were carried out before and after ESWT in the same interval as gait analysis. The results showed that there were no significant improvements in the investigated parameters at any time after ESWT; however, in horses with affected forelimbs the contralateral weightbearing asymmetry decreased significantly 72h after ESWT. Neither skin sensitivity nor thermographic imaging revealed changes that could be attributed to ESWT.  相似文献   
162.
Many orchids are currently red-listed due to changes in land use, and their future persistence will depend on management. Traditional land use like mowing is believed to favour orchids through increased survival and reproduction of established individuals, but the lack of data connecting their complex life cycle presently limits our ability to evaluate effects of management. Here we used data from 16 years of demographic monitoring to study how mowing affects population dynamics in two populations of the rare orchid Dactylorhiza lapponica. Both populations were characterized by long-lived individuals, low adult mortality and high seedling mortality. The traditional regime of mowing every second year strongly increased recruitment and reduced seed production in both populations, but had moderate effect on adult survival, growth rate and flowering probability. Population growth rate was positive for all population × treatment combinations. Traditional mowing significantly increased growth rate in both populations, and LTRE-analyses revealed that this primarily was a result of increased recruitment. The results indicate that demographic rates commonly associated with orchid persistence may be insensitive to traditional management, and underscores the importance of seed production and recruitment to maintain population growth in this long-lived species. The combination of low establishment success and no seed bank makes D. lapponica dependent on high seed input. Our results suggest that D. lapponica would benefit most from traditional mowing performed after seed dispersal in the study areas, but also suggest a high probability of future survival in the absence of mowing.  相似文献   
163.
Rhododendron maximum L., a spreading understory shrub, inhibits overstory regeneration and alters forest community structure in southern Appalachian hardwood forests. Using paired plots and reciprocal litter transplants in forests with and without R. maximum cover, we examined the influence of R. maximum on litter mass and quality, N cycling and soil extracellular enzymes. Standing stocks of soil organic matter, soil N, leaf litter mass and fine root biomass were greater in forests with R. maximum than those without. Tannin extracts from R. maximum foliage, and leaf litter and fine roots collected under R. maximum had a relatively high capacity to precipitate protein compared to extracts from trees. Across the growing season, soil inorganic N availability was generally lower under R. maximum, mostly due to reduced NO3 availability. Our data suggest that R. maximum litter alters N cycling through the formation of recalcitrant polyphenol–organic N complexes. Soil extracellular enzymes indicate the potential processing rates of organic substrates. Between forest types, polyphenol oxidase activity was greatest in R. maximum O horizons, regardless of litter type, suggesting that the local microbial community can better degrade and access protein–tannin-complexed N. Protease activity did not differ between forest types, but was greater on R. maximum leaf litter than hardwood leaf litter. The alteration of the N cycle via the formation of polyphenol–organic N complexes may contribute to hardwood seedling suppression, while the enzymatic release of these complexes by ericoid mycorrhizal fungi may increase N acquisition for R. maximum and contribute to its expansion in southern Appalachian forests.  相似文献   
164.
Two samples of tartary buckwheat (Fagopyrum tataricum Gaertn.) from China and one from Luxembourg were studied by high-performance liquid chromatography (HPLC) to reveal the possibilities of growing tartary buckwheat herb as a possible source of rutin, quercetin, and quercitrin. The content of rutin was determined as up to 3% dry weight (DW) in tartary buckwheat herb. Quercitrin values were in the range of 0.01-0.05% DW. Only traces of quercetin were detected in just some of the samples. Tartary buckwheat seeds contained more rutin (about 0.8-1.7% DW) than common buckwheat seeds (0.01% DW). Rutin and quercetin content in seeds depends on variety and growing conditions. Tartary buckwheat seeds contained traces of quercitrin and quercetin, which were not found in common buckwheat seeds.  相似文献   
165.
As part of a recent task under the EPRI Analytical Methods Qualification Program (RP 1851), TRW has surveyed the methods available for monitoring metal species in typical utility aqueous discharge streams. Methods for determining the individual species of these metals can become important in a regulatory sense as the EPA transitions to assessment of environmental risk based on bioavailability. For example, EPA considers methyl mercury and Cr(VI) much more toxic to the aquatic environment than inorganic mercury or Cr(III). The species of a given element can also differ in their transport and bioaccumulation. Methods for speciation generally include a selective separation step followed by standard metals analysis. Speciation, therefore, is mainly derived from the separation step and not from the method of final quantitation. Examples of separation/analysis include: selective extraction followed by graphite furnace atomic absorption or ICP-MS; separation by GC followed by metals detection; chelation and/or direct separation by LC followed by UV measurement or metals detection; and ion chromatography with conductivity, UV, or metals detection. There are a number of sampling issues associated with metal species such as stabilization (maintaining oxidation state), absorption, and filtration that need to be addressed in order to obtain and maintain a representative sample for analysis.  相似文献   
166.
The effects of apple polyphenols on melanogenesis in B16 mouse melanoma cells were investigated. The inhibitory effect of apple polyphenols was stronger than that of arbutin or kojic acid. Three polyphenol fractions (phenolic acid derivatives, procyanidins and other flavonoids) were isolated, and the procyanidins were fractionated according to the degree of polymerization using normal-phase chromatography. The procyanidin trimer-to-pentamer fractions were found to have the most pronounced effect on melanogenesis. Furthermore, each procyanidin fraction inhibited mushroom tyrosinase. No correlation between the degree of procyanidin polymerization and tyrosinase inhibitory activity was observed. Nevertheless, these observations suggest that procyanidins are effective inhibitors of tyrosinase.  相似文献   
167.
试验旨在研究山豆根多糖(SSP)对猪肺泡巨噬细胞3D4/2感染猪圆环病毒Ⅱ型(Porcine circovirus virus Ⅱ type,PCV2)后炎性因子水平的影响。本试验设空白对照组、PCV2感染组、脂多糖(LPS)对照组和3种浓度(100、200和400 μg/mL)的山豆根多糖组,采用PCV2体外感染猪肺泡巨噬细胞,在培养液中分别加入100、200和400 μg/mL山豆根多糖培养24 h后收集样品,用酶联免疫吸附法(ELISA)测定细胞分泌单核细胞趋化蛋白-1(MCP-1)、白细胞介素-8(IL-8)水平和胞内环氧合酶-1(COX-1)、环氧合酶-2(COX-2)的酶活性,实时荧光定量PCR和Western blotting法分别检测诱导型一氧化氮合酶(iNOS)、COX-2基因及其蛋白表达。结果显示,PCV2感染猪肺泡巨噬细胞后极显著提高了MCP-1、IL-8分泌水平和细胞内COX-1、COX-2酶活性(P<0.01),iNOS、COX-2 mRNA和蛋白表达水平均极显著提升(P<0.01);100、200、400 μg/mL山豆根多糖处理后,3D4/2细胞MCP-1、IL-8分泌水平和细胞内COX-1、COX-2酶活性均显著或极显著降低(P<0.05;P<0.01),其中400 μg/mL山豆根多糖处理后效果最显著,细胞内iNOS、COX-2基因mRNA表达水平同样显著或极显著降低(P<0.05;P<0.01);100、200、400 μg/mL山豆根多糖处理后,显著或极显著抑制了由PCV2诱导的iNOS蛋白表达量的增加(P<0.05;P<0.01),经200、400 μg/mL山豆根多糖处理后显著抑制COX-2蛋白表达量的增加,400 μg/mL山豆根多糖处理效果最佳。综上所述,山豆根多糖可在一定程度上抑制PCV2感染所引起的促炎症因子mRNA表达的升高及其蛋白的表达,起到一定的缓解炎症的作用。  相似文献   
168.
169.
Transfaunation is supposed to stimulate normal rumen function and has been used as an ancillary treatment for indigestion. Although it is widely recommended, there are little research data on the efficacy and the necessary volume. The objective of the prospective clinical trial was the evaluation of the therapeutic efficacy of two different transfaunation volumes which can be obtained under practical conditions. Forty-five cattle suffering from indigestion were included in the study. A scoring system for the classification of rumen fluid was used. Scores were given in accordance with the importance of the parameter as an indication of microbial dysfunction. Animals with disturbed rumen fluid composition and activity were randomly assigned into 3 groups. Group 1 received 1 L of rumen fluid, group 2 received 5 L of rumen fluid and group 3 (control group) received 5 L of body temperature water. Rumen fluid analysis was repeated on days 1 and 4 after transfaunation. The feed intake of the animals was recorded. After the transfaunation of 1 L and 5 L, the rumen fluid score improved significantly from day 0 to days 1 and 4. Rumen fluid samples in the control group showed no significant improvement from day 0 to day 1. No significant differences were observed between the two treatment groups. But significant differences between the improvement of group 1 and the control group on days 1 and 4 and significant differences between group 2 and the control group on day 1 were detected. Small volumes of rumen fluid are easily obtainable by stomach tubes fitted with suction pumps. In summary, the transfaunation of as little as 1 L of rumen fluid caused significant improvement in the activity of rumen flora in cows suffering from indigestion.  相似文献   
170.
A ten-year-old male standard dachshund was presented with a history of neck pain and progressive gait disturbances. Following a neurological examination and diagnostic imaging, including CT, a neoplastic lesion involving the third and fourth cervical vertebrae was suspected. The lesion included an extradural mass on the right side of the spinal canal causing a local compression of the cervical cord. Surgery, using a modified dorsal laminectomy procedure, was performed in order to decompress the cervical spinal cord. Histopathological examination of the extradural mass indicated that the tumour was a chondroid chordoma. Following discharge, the quality of life for the dog was very good for a sustained period, but clinical signs recurred at 22 months. The dog was euthanased 25 months post-surgery. On post-mortem examination, a regrowth of neoplastic tissue was found to have infiltrated the bone and spinal cord at C3-C4. This is the first report to show that palliative surgery can offer successful long-lasting treatment of chondroid chordoma of the cervical spine in the dog.  相似文献   
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