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排序方式: 共有214条查询结果,搜索用时 78 毫秒
41.
Drogan D Klipstein-Grobusch K Dierkes J Weikert C Boeing H 《Public health nutrition》2006,9(4):465-471
OBJECTIVE: To assess the relationship between intake of dietary folate equivalents and risk of myocardial infarction in a German cohort. DESIGN: Intake of dietary folate equivalents was assessed by a validated food-frequency questionnaire. Cox proportional hazard models were used to evaluate the association between intake of dietary folate equivalents and risk of myocardial infarction. SETTING: The European Prospective Investigation into Cancer and Nutrition (EPIC)-Potsdam cohort, Germany. SUBJECTS: Subjects were 22,245 apparently healthy non-users of vitamin supplements aged 35-64 years. RESULTS: During 4.6 years of follow-up, 129 incident cases of myocardial infarction were identified. Compared with intake below the median (103 microg), higher intake of dietary folate equivalents was associated with a multivariate-adjusted hazard ratio (HR) of 0.57 (95% confidence interval (CI) 0.36-0.91). The inverse association of folate intake and myocardial infarction risk was stronger in participants with an ethanol intake equal to or above the sex-specific median (HR=0.37, 95% CI 0.18-0.79) and attenuated in those with a low ethanol intake (HR=0.67, 95% CI 0.37-1.22). CONCLUSION: An increased intake of dietary folate equivalents was observed to be associated with decreased risk of myocardial infarction in a German study population, pointing towards the importance of folate intake with respect to primary prevention of myocardial infarction. 相似文献
42.
Caterina Nocentini Bertrand Guenet Giacomo Certini Cornelia Rumpel 《Soil biology & biochemistry》2010,42(9):1472-1478
Effects of fire on the functioning of the soil microbial community are largely unknown. In this study, we addressed the charcoal mineralisation potential of microbial inocula extracted from burned and unburned soil. The mineralisation of charcoal was analysed during a 1 month incubation experiment under controlled conditions with and without substrate addition. The aim of the study was to elucidate (1) the indirect effect of fire on the functioning of the soil microbial community in terms of charcoal degradation and (2) the possibility to stimulate this degradation by addition of two substrates of increasing complexity. Our conceptual approach included the monitoring of CO2 emission from microcosms containing laboratory-made charcoal and microbial inocula from burned and unburned soil with and without 13C labelled glucose and cellulose.Our results showed higher charcoal mineralisation without substrate addition in microcosms with the inocula from unburned soil compared to burned soil. Charcoal mineralisation was stimulated by the addition of glucose, whereas cellulose addition did not induce a priming effect. We observed a higher stimulation of charcoal mineralisation induced by glucose for the inoculum from burned soil compared to the inoculum from unburned soil. We concluded that fire did affect the functioning of the soil microbial community in terms of charcoal degradation and that the important priming effect induced by glucose may be explained by an increase of the overall microbial activity, rather than selective stimulation of charcoal degrading microbial communities. 相似文献
43.
Jugl-Chizzola M Spergser J Schilcher F Novak J Bucher A Gabler C Hagmüller W Zitterl-Eglseer K 《Berliner und Münchener tier?rztliche Wochenschrift》2005,118(11-12):495-501
The aim of the study was to test Thymi herba (1.66% v/w essential oil with 39% p-cymene and 32% thymol) in the rearing period of piglets as feed additive. Therefore, two feeding trials were performed with piglet groups ranging from 17 to 22 animals each. Either 10 g of Thymi herba/kg feed (Thymi herba group), 10 mg flavophospholipol/kg feed (flavophospholipol group) or nothing (control group) was added to the animals' feed. No significant differences in the performance parameter daily weight gain among any groups were recorded. No differences concerning feed efficiency or isolation of haemolytic E. coli serotypes were shown. In addition, the antibacterial activity of the essential oil of Thymi herba against 39 haemolytic E. coli isolates from the same weaners was investigated in vitro by disk diffusion, minimum inhibitory concentration and bactericidal concentration testing. In contrast to the feeding results, the essential oil of the thyme batch fed showed antibacterial activity against all haemolytic E. coli investigated. This interesting antibacterial potential of Thymi herba prompts further investigations as to its value as feed additive. 相似文献
44.
Cornelia I. Gunkel Dr med vet MRCVS Alexander Valverde DVM DVSc DACVA Timothy E. Morey MD Jorge Hernández MVZ MPVM PhD Sheilah A. Robertson BVMS PhD DACVA DECVA 《Journal of Veterinary Emergency and Critical Care》2004,14(3):187-195
Objective: To compare the partial CO2 rebreathing method (non‐invasive cardiac output [NICO]) and the lithium dilution method (lithium dilution cardiac output [LiDCO]) for cardiac output (CO) measurement in anesthetized dogs. Design: Prospective study. Setting: College of Veterinary Medicine, University of Florida. Animals: Six adult dogs (weight range 22–25.4 kg). Interventions: All animals were instrumented for CO determinations using the LiDCO and NICO methods. Direct blood pressure, heart rate, arterial blood gases, end‐tidal isoflurane (ETI), and CO2 concentrations were monitored throughout the study. CO was manipulated with dobutamine and isoflurane to allow for intermediate, low, and high CO determinations in that order using LiDCO and NICO. Measurements and main results: A 1.5% ETI produced the intermediate rate of CO, a constant‐rate infusion of dobutamine (1–4 μg/kg/min) and 1.1% ETI, the highest rate, and 2.5–3% ETI, the lowest rate. Measurements were obtained in duplicate or triplicate for the LiDCO and continuously for the NICO method after achieving a stable hemodynamic plane for at least 15 minutes at each level of CO, allowing 5 minutes between measurements. Forty‐seven comparisons were determined. The correlation coefficient (r) between the 2 methods was 0.888 for all determinations. The mean LiDCO and NICO from 47 measurements were 155.9±78.7 mL/kg/min (range, 49.6–303.2) and 146.6±62.9 mL/kg/min (50–290.3), respectively. The bias between LiDCO and NICO estimations was 9.3 (?60.7 to +79.4) mL/kg/min (mean and 95% confidence interval). The mean (mL/kg/min) of the differences of LiDCO–NICO was 1.11 × NICO. The relative error was 2.4±24.7%. As CO increased, the relative difference between the methods also increased. Conclusions: The NICO is a viable non‐invasive method for CO determination in the dog and compares well with the LiDCO. 相似文献
45.
In the present study, the influence of stress from handling and transport on some frequently examined blood parameters of racing pigeons was evaluated. After 3 hr, there was a highly significant (P < 0.01) increase in the number as well as in the percentage of heterophils and decrease of lymphocytes. In clinical chemistries, increases of creatine kinase and glucose and a decrease of uric acid were observed. There was a mean decrease of the total white blood count of >15% that was less significant (P < 0.05). Changes in lactate dehydrogenase, basophils, and monocytes did not prove to be significant; eosinophils, aspartate aminotransferase, total protein, and the packed cell volume were not influenced by stress. 相似文献
46.
Normal structure and age-related changes of the equine retina 总被引:2,自引:2,他引:0
Ehrenhofer MC Deeg CA Reese S Liebich HG Stangassinger M Kaspers B 《Veterinary ophthalmology》2002,5(1):39-47
Investigations of the pathophysiology of ocular diseases require a detailed knowledge of the microanatomy of the eye. The available information is still inadequate for the equine retina despite the importance of eye diseases in equine medicine. Here we provide a comprehensive analysis of the histologic features of the horse eye as a reference for future studies. Thirty normal eyes of 15 healthy horses were examined immediately after slaughter. The retina of the horse differs considerably in the degree and quantity of neurons and glial elements as well as in vascular patterns compared to the retina of other domestic animals. Morphometric analysis revealed that the thickness of the retina varies between 80 microm at the ora serrata and 250 microm medial to the optic disc. Approximately 90% of the equine retina is comparatively thin (< 130 microm). This is a physiologic response to the distance that oxygen can diffuse in avascular retina. Ganglion cells form a single layer in all parts of the retina. The majority of ganglion cells are very large Nissl-positive cells. Small Nissl-negative ganglion cells are less abundant. A high ganglion cell density is found only in the central area. Vascularization is virtually absent from the retina with the exception of a narrow strip around the disc of the optic nerve, as revealed by lectin histochemistry. Light microscopy of the eyes of older horses repeatedly revealed cystoid degenerations in the retina adjacent to the pars plana of the ciliary body, as well as a destruction of the regular layering of the peripheral region of the retina. 相似文献
47.
48.
Braus BK Hauck SM Amann B Heinrich C Fritsche J Köstlin R Deeg CA 《Veterinary immunology and immunopathology》2008,124(1-2):177-183
Sudden acquired retinal degeneration syndrome (SARDS) is a disease characterised by sudden and bilateral vision loss of dogs. Previous studies failed to identify the underlying cause [Mattson, A., Roberts, S.M., Isherwood, J.M.E., 1992. Clinical features suggesting hyperadrenocorticism associated with sudden acquired retinal degeneration syndrome in a dog. J. Am. Anim. Hosp. Assoc. 28, 199-202; Van der Woerdt, A., Nasisse, M.P., Davidson, M.G., 1991. Sudden acquired retinal degeneration in the dog: clinical and laboratory findings in 36 cases. Prog. Vet. Comp. Ophthamol. 1, 11-18] and earlier investigations about the occurrence of anti-retinal antibodies in SARDS patients showed inconsistent results. To provide a novel approach to those findings we designed a more detailed study. Autoantibodies of SARDS patients and normal controls were tested against the purified autoantigens S-antigen and cellular retinaldehyde binding protein (CRALBP) that play a role in human autoimmune uveitis. Next we tested the autoantibody binding pattern to whole retinal lysate. No difference in the incidence of autoantibodies could be found between SARDS patients and healthy controls while testing the well-known autoantigens S-antigen and CRALBP. Potential novel, yet unknown autoantigens were identified by a screening test using the retinal proteome as an autoantigenic source. In SARDS patients and normal controls, several retinal proteins were bound by IgG antibodies, but one band was strongly marked by SARDS patients. That band was excised, subjected to mass spectrometry (matrix-assisted laser desorption/ionisation-time of flight (MALDI-TOF/TOF)) and identified as neuron-specific enolase. Binding of the IgG autoantibodies of SARDS-affected dogs to this protein was verified using purified NSE, revealing 25% of NSE autoantibody-positive SARDS patients and 0% of negative controls. Our findings indicate that at least some dogs with SARDS have autoantibodies against NSE, although it is unclear whether these play a causative role in SARDS or whether they are the result of retinal destruction by another mechanism. 相似文献
49.
This review focuses on smart nano-materials built of stimuli-responsive (SR) polymers and will discuss their numerous applications in the biomedical field. The authors will first provide an overview of different stimuli and their corresponding, responsive polymers. By introducing myriad functionalities, SR polymers present a wide range of possibilities in the design of stimuli-responsive devices, making use of virtually all types of polymer constructs, from self-assembled structures (micelles, vesicles) to surfaces (polymer brushes, films) as described in the second section of the review. In the last section of this review the authors report on some of the most promising applications of stimuli-responsive polymers in nanomedicine. In particular, we will discuss applications pertaining to diagnosis, where SR polymers are used to construct sensors capable of selective recognition and quantification of analytes and physical variables, as well as imaging devices. We will also highlight some examples of responsive systems used for therapeutic applications, including smart drug delivery systems (micelles, vesicles, dendrimers...) and surfaces for regenerative medicine. 相似文献
50.
Walter W. WENZEL Cornelia MESMER Eric J. FLORIDA Markus PUSCHENREITER Holger KIRCHMANN 《土壤圈》2022,32(4):543-554
Diffusive gradients in thin films (DGT) measurements have been shown to outperform other phosphorus (P) tests in soils with strong P sorption, but this has not been confirmed for moderately weathered European soils. We compared the performance of DGT in predicting wheat grain yield in Swedish long-term fertility experiments with those of standard intensity (water-extractable P (P-H2O)) and quantity (ammonium lactate-extractable P (P-AL)) tests. A Mitscherlich-type model was used to fit wheat yield response to P application rates (0, 15, 30 or 35, and 45 kg P ha-1 year-1) in each individual trial replicate to estimate the maximum yield. For trials with clear plateau-type yield responses and the goodness of fit (R2) > 0.75, relative yields (RYs) were calculated for each P treatment and plotted against the soil P test results (n=143). The goodness of the Mitscherlich-type fits decreased in the following order:DGT-measured P (P-DGT) (R2=0.35) > P-H2O (R2=0.18) > P-AL (R2=0.13). When excluding soils with P-AL:P-DGT ≥ 0.1 L g-1, R2 was considerably improved to 0.55 for P-AL, 0.46 for P-H2O, and 0.65 for P-DGT (n=61). At 95% of maximum yield, the upper limit of P deficiency for P-DGT was 44.8 (the soils with P-AL:P-DGT < 0.1 L g-1) and 61.9 μg L-1 (all soils), falling within the range reported for other European and Australian soils (6.0-142 μg L-1). We show that in the investigated Swedish soils, DGT performed better than the quantity and intensity tests, which is attributed to its ability to capture P diffusion and resupply from the soil solid phase, similar to plant roots in the rhizosphere. 相似文献