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11.
The aim of this study was to determine serum levels of natriuretic peptide precursors (NT‐proANP and NT‐proBNP) during pregnancy in brachycephalic bitches. Fifteen healthy multiparous bitches were selected for this prospective study. Serum levels of NT‐proANP and NT‐proBNP were measured during anoestrous and at 14, 35, 42, 49 and 56 days (2nd, 5th, 6th, 7th and 8th weeks) of pregnancy. Fourteen animals had normal gestations, and one bitch developed single foetus syndrome. The natriuretic peptide levels of this animal were not included in this study; however, it is important to report that its NT‐proANP levels were four times greater than those of normal patients. There was no significant difference (p = 0.072) in NT‐proBNP levels between anoestrous (0.20 ± 0.10 ng/ml) and the different pregnancy weeks (0.27 ± 0.12 ng/ml). There was a positive correlation (p < 0.0001) between NT‐proANP and gestational age, and the levels of this marker increased significantly (p < 0.0001) during the 6th (0.26 ± 0.06 ng/ml), 7th (0.28 ± 0.04 ng/ml) and 8th weeks (0.29 ± 0.05 ng/ml) when compared to anoestrous (0.18 ± 0.02 ng/ml). NT‐proANP serum levels are correlated with gestational development and may be indicative of cardiovascular adaptation in canine brachycephalic pregnancy.  相似文献   
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The purpose of this study, in which the farm was used as the statistical unit, was to find factors affecting mink mortality under farm conditions. Mortality was hypothesised to be affected by factors including, among others, variables describing the amount (level) and variation in composition and quality of the feed. Other explanatory variables applied in the study included farm size and age. Factor analyses were performed for variables of feed composition and quality in order to condense the variable information and to facilitate the selection of explanatory variables. This report presents a preliminary regression model for female mink mortality factors describing feed level and variation, and farm size, as explanatory variables. The regression model emphasized among other factors the importance of a constant albumin quality and a constant energy level.  相似文献   
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Transesophageal echocardiography (TEE) enhances our ability to see the patent ductus arteriosus in the dog. The improved visualization may potentially improve our ability to perform transcatheter coil embolization in patients that are more likely to have a successful outcome. This report uses still and video images to detail the specifics of coil embolization as performed with the assistance of TEE and compares the images with those of angiography, surgery and postmortem examination.  相似文献   
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OBJECTIVES: To identify and describe dietary patterns in a cohort of pregnant women and investigate whether the dietary patterns are associated with dietary intake and sociodemographic factors. DESIGN: Mothers entering the Finnish Type 1 Diabetes Prediction and Prevention (DIPP) Nutrition Study in 1997-2002 were retrospectively asked to complete a food-frequency questionnaire concerning their diet during pregnancy. Principal components analysis was used to identify dietary patterns. SETTING: Finland. SUBJECTS: Subjects were 3730 women with a newborn infant carrying increased genetic susceptibility to type 1 diabetes mellitus. RESULTS: Seven factors were identified and named. Energy intake correlated positively with 'Healthy', 'Fast food', 'Traditional bread', 'Traditional meat' and 'Coffee' patterns and inversely with the 'Alcohol and butter' pattern. Intake of dietary fibre correlated positively with 'Healthy', 'Traditional bread' and 'Low-fat foods' patterns and inversely with the 'Alcohol and butter' pattern. The seven dietary patterns seemed to account for relatively large proportions of the variance in energy and nutrient intakes except for the intake of vitamin D, vitamin C, carotenoids and calcium. Maternal age and higher level of education were associated with higher scores on 'Healthy', 'Low-fat foods' and 'Alcohol and butter' patterns. CONCLUSION: Principal components analysis produced seven dietary patterns which may be useful for further research concerning maternal diet and health outcomes among both mothers and their offspring.  相似文献   
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The study of quantitative trait’s expression over time helps to understand developmental processes which occur in the course of the growing season. Temperature and other environmental factors play an important role. The dynamics of haulm senescence was observed in a diploid potato mapping population in two consecutive years (2004 and 2005) under field conditions in Finland. The available time series data were used in a smoothed generalized linear model to characterize curves describing the senescence development in terms of its onset, mean and maximum progression rate and inflection point. These characteristics together with the individual time points were used in a Quantitative trait loci (QTL) analysis. Although QTLs occurring early in the senescence process coincided with QTLs for onset of senescence, the analysis of the time points made it difficult to study senescence as a continuous trait. Characteristics estimated from the senescence curve allowed us to study it as a developmental process and provide a meaningful biological interpretation to the results. Stable QTLs in the two experimental years were identified for progression rate and year-specific QTLs were detected for onset of senescence and inflection point. Specific interactions between loci controlling senescence development were also found. Epistatic interaction between QTLs on chromosomes 4, 5 and 7 were detected in 2004 and pleiotopic effects of QTLs on chromosomes 3 and 4 were observed in 2005.  相似文献   
18.
Improving broad specificity hapten recognition with protein engineering   总被引:1,自引:0,他引:1  
Sulfa antibiotics (sulfonamides) are derivatives of p-aminobenzenesulfonamide that are widely used in veterinary medicine. Foods derived from treated animals may be contaminated with these drugs. However, current immunobased sulfonamide detection methods are unfit for screening of products because they are either too insensitive or specific for a few compounds only. An immunoassay capable of detecting all sulfas in a single reaction would be ideal for screening. For development of a binder capable of binding all sulfas, a protein engineering approach was chosen and the properties of monoclonal antibody 27G3 were improved with mutagenesis followed by selection with phage display. Several different mutant antibodies were isolated. The cross-reaction profile of the best mutant antibody was significantly improved over that of the wild-type antibody: it was capable of binding 9 of the tested 13 sulfonamides within a narrow concentration range and also bound the rest of the sulfas, albeit within a wider concentration range.  相似文献   
19.
Many freshwater ecosystems face severe threats from anthropogenic disturbances, yet little is known about the degree to which their biotic communities have been degraded by human activities. We analysed temporal changes and persistence of bryophyte communities in 40 springs in eastern Finland by comparing field surveys conducted in 1986 and 2000. During that period, some springs had remained in a near-pristine state, while others had undergone varying degrees of disturbance from forest management, drainage, and water abstraction. Several spring bryophytes (e.g., Philonotis fontana) declined between the study years, whereas Sphagnum mosses (e.g., Sphagnum warnstorfii) increased in abundance. Species richness of spring bryophytes declined significantly from 1986 to 2000, irrespective of bryophyte group (spring vs. other bryophytes) and spring condition (severely disturbed vs. unaltered springs). Bryophyte cover also decreased dramatically from 1986 to 2000, but this effect was related to both spring condition and bryophyte type. Spring bryophytes lost much of their cover in severely altered springs, while in unaltered springs they remained relatively stable through time. No such trend was observed for other, habitat generalist bryophytes. Persistence and stability of bryophyte communities showed significant, albeit rather weak, relationships with spring condition, with communities in unaltered springs being more persistent than those in altered springs. Given the importance of springs to boreal forest and aquatic biodiversity, restoration of degraded springs is a major challenge to maintaining and conserving biodiversity of boreal landscapes.  相似文献   
20.
In humans, polyphenol supplementation studies have resulted in inconsistent findings in lipid peroxidation. Our aim was to investigate the effects of a 4-week consumption of polyphenol-rich phloem on serum lipids and lipid peroxidation in the hydrophilic fraction of serum and on isolated lipoproteins. We conducted a randomized double-blind supplementation study consisting of 75 nonsmoking hypercholesterolemic men. Participants consumed 70 g daily of either rye bread (placebo) or phloem-fortified rye bread containing 31 mg (low polyphenol, LP) or 62 mg (high polyphenol, HP) of catechins. The ex vivo susceptibility of total serum lipids and VLDL and LDL to oxidation after copper induction was measured as a lag time to the maximal oxidation rate at the baseline and after the supplementation. In the HP group, an increase in the oxidation resistance of total serum lipids was observed (11.4%), while no effect was seen in the LP group (-0.8%) or in the placebo group (-1.0%) (p = 0.007). No differences were observed in the oxidation resistance of VLDL and LDL between the study groups. The phloem also increased in vitro oxidation resistance of serum lipids and radical scavenging activity (DPPH.) in a dose-dependent manner. Our results suggest that polyphenols may inhibit lipid peroxidation in the hydrophilic fraction of serum.  相似文献   
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