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排序方式: 共有196条查询结果,搜索用时 15 毫秒
161.
162.
C F Duffy G F Killeen C D Connolly R F Power 《Journal of agricultural and food chemistry》2001,49(7):3408-3413
Yucca schidigera Roezl ex Ortgies, family Lillaceae, was fractionated with butan-1-ol to yield a butanol extractable fraction (BE; saponin fraction) and a non-butanol fraction (NBE; non-saponin fraction). Four groups of eight male rats were allowed ad libitum access to diets supplemented with water (control) or 200 mg x kg(-1) total Y. schidigera (TOT) or 200 mg x kg(-1) of each of the fractions (NBE or BE). The effects of dietary supplementation with the fractions and their interactions in TOT were analyzed according to the factorial experimental design by two-way analysis of variance. All three supplementation groups displayed significantly reduced serum urea levels (P < 0.05). The TOT and NBE fractions were found to significantly increase serum insulin levels (P < 0.01) in the absence of any fluctuations in serum glucose levels. Urea cycle enzyme activities, namely, arginase (EC 3.5.3.1) and argininosuccinate lyase (EC 4.3.2.1), were significantly decreased (P < 0.05) in vivo, although no effect was observed in vitro. Both fractions displayed effects, indicating that the active constituents are present in both fractions. 相似文献
163.
At the global scale peatlands are an important soil organic carbon (SOC) pool. They sequester, store and emit carbon dioxide and methane and have a large carbon content per unit area. In Ireland, peatlands cover between 17% and 20% of the land area and contain a significant, but poorly quantified amount of SOC. Peatlands may function as a persistent sink for atmospheric CO2. In Ireland the detailed information that is required to calculate the peatland SOC pool, such as peat depth, area and carbon density, is inconsistent in quality and coverage. The objective of this research was to develop an improved method for estimating the depth of blanket peat from elevation, slope and disturbance data to allow more accurate estimations of the SOC pool for blanket peatlands. The model was formulated to predict peat depth at a resolution of 100 ha (1 km2). The model correctly captured the trend and accounted for 58 to 63% of the observed variation in peat depth in the Wicklow Mountains on the east coast of Ireland. Given that the surface of a blanket peatland masks unknown undulations at the mineral/peat interface this was a successful outcome. Using the peat depth model, it was estimated that blanket peatland in the Wicklow Mountains contained 2.30 Mt of carbon. This compares to the previously published values ranging from 0.45 Mt C to 2.18 Mt C. 相似文献
164.
E de P Lopes JB Siqueira RO Pinho JD Guimarães AN Rocha GR de Carvalho CAA Torres 《Reproduction in domestic animals》2011,46(2):261-267
The objective of this study is to evaluate the reproductive efficiency in donors and recipient Mangalarga Marchador mares in commercial programmes of embryo transfer (ET) and the effects of some reproductive characteristics and ET methodology on conception rates in the recipient mares. A total of 1140 flushing procedures were performed and 830 embryos (72.8%) were recovered. There were no differences between the rates of embryonic recovery in the different breeding seasons (p > 0.05) and 92.8% of the recovered embryos were 8–9 days old. There was no difference in the embryonic recovery regarding the collection order from the first to the ninth embryo collection along the breeding season, as well as among mares inseminated during the foal heat or subsequent cycles (p > 0.05). Pregnancy rates observed in the total period of all reproductive seasons at 15, 30, 45 and 60 days of pregnancy were 73.4, 69.9, 66.7 and 64.5%, respectively. Differences in pregnancy rate and early embryonic loss rates were not observed between embryos transferred immediately after collection (66.8% and 13.5%) and embryos transported at room temperature for periods of <1 h (62.9% and 14.4%; p > 0.05). Pregnancy rates were higher when the interval between ovulations of donor and recipient mares remained between ?3 and ?2 days (p < 0.05), and the lowest rates were observed for intervals of ?6 days (p < 0.05) with intermediary values for intervals of ?1, 0 and +1 (p > 0.05). Embryonic loss rates, however, did not differ between intervals of ovulation’s synchronism between donor and recipient mares (p > 0.05). This flexibilization in the ovulatory synchronism between donor and recipient mares optimizes the use of recipient mares, thus reducing costs and facilitating management of horse breeding farms. 相似文献
165.
Hilary A. Levitin Kari D. Foss Devon W. Hague Sara L. Connolly Miranda Vieson Kathryn L. Wycislo Stephan Lezmi Mathew C. Lovett 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2019,48(2):282-286
Two adult male dogs (a 7‐year‐old shorthaired Chihuahua and 14‐year‐old Shih Tzu) and one adult female dog (a 9‐year‐old Maltese) presented for evaluation of new‐onset seizure activity. Magnetic resonance imaging of the brain demonstrated a large, poorly marginated T2‐weighted hyperintense, and strong contrast enhancing extra‐axial mass in each case. A surgical biopsy for histopathologic evaluation was elected in all cases, and intraoperative impression smears were successfully obtained. Intraoperative cytology identified a homogenous population of round to polygonal cells with central to eccentric nuclei, coarse chromatin, and variably amphophilic to eosinophilic granular cytoplasm. Cytologic findings led to a suspected diagnosis of granular cell tumor (GCT) in all cases. Histopathologic review identified a densely cellular, unencapsulated neoplastic mass comprised of sheets of large round to polygonal cells with abundant eosinophilic cytoplasm containing numerous eosinophilic intracytoplasmic granules, confirming the diagnosis of GCT in all cases. The cases reported here are unique in that they reveal an accurate intraoperative cytologic diagnosis of a rare canine central nervous system neoplasm. Intraoperative cytology of the intracranial masses could provide clinicians with important and quick diagnostic and prognostic information; therefore, expediting decisions made intraoperatively. Further research is warranted to determine the diagnostic accuracy of intraoperative cytology for neoplasia in veterinary patients. 相似文献
166.
167.
Ilaria Spalla Jessie Rosie Payne Kieran Borgeat Virginia Luis Fuentes David John Connolly 《Journal of Veterinary Cardiology》2018,20(3):154-164
Introduction
Hypertrophic cardiomyopathy (HCM) has a variable prognosis; left atrial size, presence of clinical signs and left ventricular systolic function have been shown to predict outcomes. Mitral annular plane systolic excursion (MAPSE) and tricuspid annular plane systolic excursion (TAPSE) assess longitudinal ventricular systolic function and are decreased in cats with HCM. The aim of the study was to ascertain whether MAPSE and TAPSE have prognostic value in HCM and if cats with pleural effusion have lower MAPSE and TAPSE than cats with pulmonary oedema.Animals
One hundred eighty-four client-owned cats diagnosed with HCM.Methods
This is a retrospective study. Echocardiography was used to diagnose HCM (end-diastolic left ventricular wall thickness ≥ 6 mm) and to measure MAPSE and TAPSE. Survival information was obtained.Results
No multivariable model including MAPSE or TAPSE could be generated in this population. Cats with pleural effusion ± pulmonary oedema had lower MAPSE measured at the interventricular septum (MAPSE IVS) and TAPSE, compared with cats with pulmonary oedema only. MAPSE IVS was the only factor predicting pleural effusion on multivariable regression model.Conclusions
Lower MAPSE and TAPSE were not independently associated with outcomes on multivariable analysis. Cats with pleural effusion ± pulmonary oedema had lower TAPSE and MAPSE IVS than cats with pulmonary oedema, and MAPSE IVS was the only predictive factor associated with the development of pleural effusion in this population. 相似文献168.
Pericardial effusion (PE) is reported in dogs as a consequence of neoplasia, primary cardiac disease or as an idiopathic condition. We describe seven dogs with systemic inflammatory disease, PE without tamponade and increased cardiac troponin I concentrations. Echocardiographic findings and adjunctive testing did not identify other known causes of PE. Resolution of the PE was documented in five of seven dogs in which follow-up echocardiography was performed, often after anti-inflammatory therapy. Resolution of PE was associated with normalisation of cardiac troponin I levels. Clinical signs had not recurred in six dogs with follow-up for more than 12 months and up to 7 years. These findings suggest an association between systemic inflammation and PE in dogs. 相似文献
169.
DR James N Webster JD White AM Marchevsky RG Cashmore M Havlicek 《New Zealand veterinary journal》2013,61(5):270-276
AbstractAIMS: To objectively compare measures of bone healing, using computed tomography (CT) in dogs following bilateral tibial tuberosity advancement (TTA), between tibiae treated with and without autogenous cancellous bone grafts.METHODS: Ten dogs with bilateral cranial cruciate ligament disease requiring surgical stabilisation were prospectively recruited to undergo single-session bilateral TTA, with only one, randomly assigned, tibia receiving bone graft in the osteotomy deficit. Bone healing at the osteotomy site was assessed using CT performed 38–70 days post-operatively. CT images were evaluated using both objective measurements of osseous bridging and subjective evaluation by six radiologists. Repeated measures ANOVA was used to compare the objective outcomes between the grafted and non-grafted tibiae.RESULTS: The mean percentage of the osteotomy deficit bridged at the lateral cortex was greater in grafted (77.6, SD 35.2%) compared to non-grafted (63.0, SD 36.5%) tibiae (p=0.001), but did not differ at the medial cortex (p=0.1). The mean minimum callus width was greater in grafted (7.2, SD 3.3 mm) compared to non-grafted (3.6, SD 2.9 mm) tibiae (p<0.001). There was no difference in mean attenuation (measured in Hounsfield units) of the callus between grafted and non-grafted tibiae (p=0.5). The grafted tibia was deemed to have superior bone healing in 50/60 subjective assessments made by radiologists.CONCLUSIONS: Superior osseous bridging was detected by CT analysis following TTA using autogenous cancellous bone grafts compared with no graft. This was shown by greater bridging percentage at the lateral cortex and formation of a broader callus. Qualitative assessments made by six radiologists also supported the conclusion that bone healing was improved by use of autogenous cancellous bone graft. CT was a useful method for assessing evidence of bone healing following TTA.CLINICAL RELEVANCE: These findings justify the application of autogenous cancellous bone graft to augment healing following TTA in dogs. 相似文献
170.
A new benzophenanthridine alkaloid, 6-[2'-ethoxy-2'-(2',4',5'-trimethoxyphenyl)] ethyl-7,8-dimethoxy-5-methyl-2,3-methylenedioxy-5,6-dihydrobenzo[c]phenanthridine named buesgeniine (1), as well as the known decarine, were isolated from the extract of the stem bark of Zanthoxylum buesgenii. In addition, three known lignans, sesamine, matairesinol dimethylether, and methylpluviatilol, were also identified. The structure of 1 was elucidated using spectroscopic methods. 相似文献