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41.
[Objectives]This study aimed to investigate the effects of ropivacaine-sufentanil epidural analgesia on labor and maternal and neonatal outcomes.[Methods]A tota...  相似文献   
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本研究利用筛选出的10对多态性高、条带清晰的SSR引物,以海南岛68份红毛丹种质为材料,进行遗传多样性分析和SSR指纹图谱的构建。结果表明:10对引物在供试材料中共检测出20个等位位点,多态性条带比例为100%,平均多态性信息含量(PIC)为0.393;对68份红毛丹种质做聚类分析,遗传相似系数为0.290~0.664;采用引物?带型组合法构建了68份红毛丹种质的指纹图谱。该结果为今后红毛丹种质鉴定和分子育种提供重要依据。  相似文献   
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In this study, films of chitosan and 2-amino-4,5,6,7-tetrahydrobenzo[<em>bem>]thiophene-3-carbonitrile (6CN), a 2-aminothiophene derivative with great pharmacological potential, were prepared as a system for a topical formulation. 6CN-chitosan films were characterized by physicochemical analyses, such as Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and scanning electronic microscopy (SEM). Additionally, the antifungal potential of the films was evaluated in vitro against three species of <em>Candidaem> (<em>C. albicansem>, <em>C. tropicalisem>, and <em>C. parapsilosisem>). The results of the FTIR and thermal analysis showed the incorporation of 6CN in the polymer matrix. In the diffractogram, the 6CN-chitosan films exhibited diffraction halos that were characteristic of amorphous structures, while the micrographs showed that 6CN particles were dispersed in the chitosan matrix, exhibiting pores and cracks on the film surface. In addition, the results of antifungal investigation demonstrated that 6CN-chitosan films were effective against <em>Candidaem> species showing potential for application as a new antifungal drug.  相似文献   
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The objective of this work was to evaluate the association between morphometric variables and carcass characteristics in Pirapitinga. We used a thousand specimens of Pirapitinga with an average weight of 1,200 g, which were stunned, slaughtered, weighed, measured, and processed for morphometric and processing yield analysis, to obtain weights, carcass and fillet yields. Initially, the linearity of the variables was verified. Pearson's simple and partial correlation tests were performed between all metrics. Track analysis was performed considering the weights and yields of carcass and filet as dependent variables and the others as independent variables. Ridge regression models were used to eliminate the effects of multicollinearity among the independent variables. Observations showed that the simple correlations between body weights and yields were superior to the partial ones in terms of magnitude. The length and circumference of the specimens were the measures most linearly associated with weight, carcass weight and fillet with rib weight. As for carcass yield and fillet yield, linear correlation coefficients were low and not significant when associated with body weights. With the path analysis, we could observe significant positive correlations between the morphometric measurements for weight, carcass weight and fillet with rib weight. The standard length, body circumference and body circumference/body height ratio are the most correlated. The latter are the most important variables in the evaluation of body weights in Pirapitinga fish. They can serve as criteria for indirect selection in searching for fish with better carcass characteristics. As for fillet and carcass yields, the morphometric variables have not shown to be efficient for indirect selection.  相似文献   
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Phenolic compounds in plant disease resistance   总被引:1,自引:0,他引:1  
We propose that an important first line in plant defense against infection is provided by the very rapid synthesis of phenolics and their polymerization in the cell wall. This rapid synthesis, which leaves no time forde novo enzyme synthesis, is regulated by the extreme pH-dependence of the hydroxylase, catalyzing the formation of caffeoyl-CoA from 4-coumaroyl-CoA. We further propose that elicitor treatment or infection causes rapid membrane changes leading to a decrease in cytoplasmic pH. This decrease would have the effect of activating the hydroxylase.  相似文献   
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Time trends in animal-disease surveillance often are evaluated on the basis of crude estimates of apparent prevalence. In addition to possible changes in the true prevalence of the condition, changes in apparent prevalence over time might reflect changes in sensitivity and/or specificity of the diagnostic classification used. To illustrate this, comparative post-mortem meat inspection data from four Danish slaughter plants sampled in 1993-1994 and 1997-1998 were used to obtain latent-class model estimates of the sensitivity and specificity of traditional and extended post-mortem meat inspection of visceral and parietal chronic pleuritis (CP), respectively.True prevalence of CP was estimated for each study period and slaughter plant by latent-class models. Estimated sensitivities of traditional post-mortem meat (TPM) inspection ranged from 28.8 to 61.4% (1993-1994) and 39.2 to 87.3% (1997-1998). An increase in sensitivity with time was seen for all slaughter plants. Estimated sensitivities of extended post-mortem meat (EPM) inspection ranged from 85.7 to 94.8% (1993-1994) and 73.8 to 93.0% (1997-1998). All estimated specificities were >93.3%.The possible association of the estimated true prevalence of CP with time (1993-1994 versus 1997-1998) was investigated with a logistic-regression model with random effects. A slight, but non-significant decrease in the odds of CP from 1994 to 1998 was found (odds ratio=0.9).In this and similar situations, one should consider conducting ongoing double-classification of samples of units followed by statistical estimation of true prevalences, sensitivities and specificities, so that decisions can be based on such estimates rather than on crude apparent prevalences.  相似文献   
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