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TORGEIR NYGÅRD 《Ibis》1999,141(1):85-90
Eggshell thickness is often expressed by means of an index based on the length, breadth and weight of the shell. The effect of the blow-hole and egg eccentricity on Ratcliffe's shell thickness index was investigated in a sample of 585 eggs from six raptor species. Corrections for the size of the hole and egg eccentricity are proposed, as is a combined formula to correct both sources of error at the same time. It is shown that by using these formulae, considerable improvements in estimates of shell thinning are obtained. These may be especially useful when sample sizes are small, which is often the case when working with species that have been reduced in numbers.  相似文献   
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The selectins interact in important normal and pathological situations with certain sialylated, fucosylated glycoconjugate ligands containing sialyl Lewisx(Neu5Acalpha2-3Galbeta1-4(Fucalpha1-3)GlcN Ac). Much effort has gone into the synthesis of sialylated and sulfated Lewisxanalogs as competitive ligands for the selectins. Since the natural selectin ligands GlyCAM-1 and PSGL-1 carry sialyl Lewisxas part of a branched Core 2 O-linked structure, we recently synthesized Galbeta1-4(Fucalpha1-3)GlcNAcbeta1-6(SE-3Galbeta1++ +-3)GalNAc1alphaOMe and found it to be a moderately superior ligand for L and P-selectin (Koenig et al. , Glycobiology 7, 79-93, 1997). Other studies have shown that sulfate esters can replace sialic acid in some selectin ligands (Yeun et al. , Biochemistry, 31, 9126-9131, 1992; Imai et al. , Nature, 361, 555, 1993). Based upon these observations, we hypothesized that Neu5Acalpha2-3Galbeta1-3GalNAc might have the capability of interacting with L- and P-selectin. To examine this hypothesis, we synthesized Galbeta1-4(Fucalpha1-3)GlcNAcbeta1-6(Neu5Acalpha2++ +-3Galbeta1-3)- GalNAc alpha1-OB, which was found to be 2- to 3-fold better than sialyl Lexfor P and L selectin, respectively. We also report the synthesis of an unusual structure GalNAcbeta1-4(Fucalpha1- 3)GlcNAcbeta1-OMe (GalNAc- Lewisx-O-methyl glycoside), which also proved to be a better inhibitor of L- and P-selectin than sialyl Lewisx-OMe. Combining this with our knowledge of Core 2 branched structures, we have synthesized a molecule that is 5- to 6-fold better at inhibiting L- and P-selectin than sialyl Lewisx-OMe, By contrast to unbranched structures, substitution of a sulfate ester group for a sialic acid residue in such a molecule resulted in a considerable loss of inhibition ability. Thus, the combination of a sialic acid residue on the primary (beta1-3) arm, and a modified Lexunit on the branched (beta1-6) arm on an O-linked Core 2 structure generated a monovalent synthetic oliogosaccharide inhibitor superior to SLexfor both L- and P-selectin.   相似文献   
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The cell bodies of pseudounipolar neurons of the trigeminal ganglia have been presumed to play a supportive role to neurites, which transmit various sensations like pain from the periphery to the brain stem. However, several studies have recently shown that these neuronal cell bodies could modulate the afferent stimuli by up-regulating various ion channels and also by increasing the synthesis of neuropeptides like calcitonin gene-related peptide (CGRP). Since voltage-sensitive calcium ion channels (VSCCs) determine neuropeptides/neurotransmitters released by neurons, the aim of the present study was to localize the various VSCCs (N-, P/Q-, L-, T- and R-types) in the trigeminal ganglia neurons by immunohistochemistry. The results showed that all the VSCCs are expressed by the cell bodies of neurons though the small-sized neurons showed higher expression of these channels. The small-sized neurons were identified by immunohistochemical localization of CGRP, the most common neuropeptide for pain transmission in the trigeminal ganglia neurons. Some of these channels (N, P/Q and T types) were also expressed on the cell surface though previous electrophysiological studies have shown the expression of all the channels on the cell surface. It is suggested that the cell bodies could play a more active role than hereto ascribed to these, in the modulation of sensory stimuli.  相似文献   
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Investigation of the diversity of malaria parasite antigens can help prioritize and validate them as vaccine candidates and identify the most common variants for inclusion in vaccine formulations. Studies of vaccine candidates of the most virulent human malaria parasite, Plasmodium falciparum, have focused on a handful of well-known antigens, while several others have never been studied. Here we examine the global diversity and population structure of leading vaccine candidate antigens of P. falciparum using the MalariaGEN Pf3K (version 5.1) resource, comprising more than 2600 genomes from 15 malaria endemic countries. A stringent variant calling pipeline was used to extract high quality antigen gene ‘haplotypes’ from the global dataset and a new R-package named VaxPack was used to streamline population genetic analyses. In addition, a newly developed algorithm that enables spatial averaging of selection pressure on 3D protein structures was applied to the dataset. We analysed the genes encoding 23 leading and novel candidate malaria vaccine antigens including csp, trap, eba175, ama1, rh5, and CelTOS. Our analysis shows that current malaria vaccine formulations are based on rare haplotypes and thus may have limited efficacy against natural parasite populations. High levels of diversity with evidence of balancing selection was detected for most of the erythrocytic and pre-erythrocytic antigens. Measures of natural selection were then mapped to 3D protein structures to predict targets of functional antibodies. For some antigens, geographical variation in the intensity and distribution of these signals on the 3D structure suggests adaptation to different human host or mosquito vector populations. This study provides an essential framework for the diversity of P. falciparum antigens to be considered in the design of the next generation of malaria vaccines.  相似文献   
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Principles

Case weights of Diagnosis Related Groups (DRGs) are determined by the average cost of cases from a previous billing period. However, a significant amount of cases are largely over- or underfunded. We therefore decided to analyze earning outliers of our hospital as to search for predictors enabling a better grouping under SwissDRG.

Methods

28,893 inpatient cases without additional private insurance discharged from our hospital in 2012 were included in our analysis. Outliers were defined by the interquartile range method. Predictors for deficit and profit outliers were determined with logistic regressions. Predictors were shortlisted with the LASSO regularized logistic regression method and compared to results of Random forest analysis. 10 of these parameters were selected for quantile regression analysis as to quantify their impact on earnings.

Results

Psychiatric diagnosis and admission as an emergency case were significant predictors for higher deficit with negative regression coefficients for all analyzed quantiles (p<0.001). Admission from an external health care provider was a significant predictor for a higher deficit in all but the 90% quantile (p<0.001 for Q10, Q20, Q50, Q80 and p = 0.0017 for Q90). Burns predicted higher earnings for cases which were favorably remunerated (p<0.001 for the 90% quantile). Osteoporosis predicted a higher deficit in the most underfunded cases, but did not predict differences in earnings for balanced or profitable cases (Q10 and Q20: p<0.00, Q50: p = 0.10, Q80: p = 0.88 and Q90: p = 0.52). ICU stay, mechanical and patient clinical complexity level score (PCCL) predicted higher losses at the 10% quantile but also higher profits at the 90% quantile (p<0.001).

Conclusion

We suggest considering psychiatric diagnosis, admission as an emergencay case and admission from an external health care provider as DRG split criteria as they predict large, consistent and significant losses.  相似文献   
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