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991.
摘要 目的:探究血清髓过氧化物酶(MPO)水平与急诊经皮冠状动脉介入(PCI)治疗患者造影剂所致急性肾损伤(CI-AKI)及预后的关系及其预测价值。方法:选取2020年3月-2021年2月于安徽医科大学第二附属医院行急诊PCI术的381例急性心肌梗死患者,收集其临床资料并于术前12 h内检测其血清MPO水平;根据术后有无发生CI-AKI分为CI-AKI组(n=34)和非CI-AKI组(n=347)。多因素Logistic回归分析急诊PCI术后患者发生CI-AKI影响因素,受试者工作特征(ROC)曲线评估MPO预测CI-AKI的效能;根据最佳截断值将患者分为高MPO组和低MPO组,对患者随访12个月,采用Kaplan-Meier生存曲线分析高MPO组、低 MPO组的累积主要不良心血管事件(MACE)发生率。结果:CI-AKI组合并高血压、糖尿病、高血脂、吸烟史占比多于非CI-AKI组,MPO水平、肌酐水平、造影剂用量高于非CI-AKI组(P<0.05)。经多因素Logistic回归分析显示,糖尿病、高MPO及肌酐水平为影响患者急诊PCI术后发生CI-AKI的危险因素(P<0.05)。ROC曲线分析显示,术前血清MPO水平预测急诊PCI术后CI-AKI的曲线下面积(AUC)为0.726,最佳截断值为491.12 μg/L,灵敏度58.80%、特异度76.50%。术后1年患者发生MACE共95例,发生率为24.93%。Kaplan-Meier生存曲线显示,高MPO组MACE发生率27.37%高于低MPO组22.77%(P<0.05)。结论:急诊PCI术后发生CI-AKI的患者血清MPO水平显著提升,与患者预后存在关联,是CI-AKI的危险因素,具有较高的特异度,是预测急诊PCI术后发生CI-AKI的有效辅助指标。  相似文献   
992.
Miao G 《Bioscience reports》2001,21(3):287-292
In order to provide a scientific basis for a unified standard of the reference value of erythrocyte sedimentation rate (ESR) in China, the reference value of healthy people's ESR has been collected. The relationship between the reference value of ESR and geographical factors is examined in this paper. Altitude is the most important factor affecting the reference value of ESR, which decreases with increasing altitude; the relationship is quite significant. The method of stepwise regression analysis was used to deduce two regression equations: 1=12.08-0.00222X1+0.00114X5 ± 2.95, 2=18.81-0.00323X1+0.239X4 ± 4.70. If the geographical factor value of a particular area in China is known, the reference value of ESR of Chinese people can be calculated by means of the regression equations. Furthermore, the dependence on geographical factors in China can be classified as six districts: Qingzang, Southwest, Northwest, Southeast, North and Northeast.  相似文献   
993.
The use of semiochemicals for manipulation of the pollen beetle Meligethes aeneus (Fabricius) (Coleoptera: Nitidulidae) is being investigated for potential incorporation into a push‐pull control strategy for this pest, which damages oilseed rape, Brassica napus L. (Brassicaceae), throughout Europe. The response of M. aeneus to non‐host plant volatiles was investigated in laboratory assays to establish whether they have any effect on host plant location behaviour. Two approaches were used. First a novel, moving‐air bioassay using air funnels was developed to compare the response of M. aeneus to several non‐host plant essential oils. The beetles avoided the host plant flowers in the presence of non‐host volatiles, suggesting that M. aeneus uses olfactory cues in host location and/or acceptance. The results were expressed as ‘repellency values’ in order to compare the effects of the different oils tested. Lavender (Lavendula angustifolia Miller) (Lamiaceae) essential oil gave the highest repellency value. In addition, a four‐arm olfactometer was used to investigate olfactory responses, as this technique eliminated the influence of host plant visual and contact cues. The attraction to host plant volatiles was reduced by the addition of non‐host plant volatiles, but in addition to masking the host plant volatiles, the non‐host volatiles were avoided when these were presented alone. This is encouraging for the potential use of non‐host plants within a push‐pull strategy to reduce the pest colonisation of crops. Further testing in more realistic semi‐field and field trials is underway.  相似文献   
994.
In tropical areas worldwide, more than 1000 terrestrial species of invertebrates are used as food. For populations of Amazonian areas, different species of insects and other invertebrates serve as nourishing food sources. Here, we document the composition and nutritional quality of some invertebrates consumed in Venezuelan Amazonia, including termites (Isoptera) and earthworms (Glossoscolecidae) eaten by the Ye'Kuana (Makiritare) and caterpillars (Lepidoptera) and grubs (Coleoptera: Scarabaeidae) consumed by the Yanomamo. Consumption of 100 g of any of these invertebrates contributed 1.2–9.4 percent of the daily fat requirement and 26–144 percent of the protein daily requirement for an adult male. The sample of caterpillars regularly eaten by these peoples was rich in beta carotene (provitamin A), and a 100 g ingestion guaranteed 323 percent of the recommended daily intake of vitamin A. The greatest amount of alpha tocopherol was provided by the consumption of the smoked earthworms (36.7%). Earthworms and termites contained high levels of sterols, mainly cholesterol. The consumption of these animals by tropical human populations represents not only an important traditional habit but also, considering their nutritional composition, a substantial contribution to the human diet.  相似文献   
995.
Structural determinants of the rate of protein folding   总被引:3,自引:0,他引:3  
To understand the mechanism of protein folding and to assist rational design of fast-folding, non-aggregating and stable artificial enzymes, it is essential to determine the structural parameters which govern the rate constants of folding, kf. It has been found that -logkf is a linear function of the so-called chain topology parameter (CTP) within the range of 10(-1)s(-1)< or = kf < or =10(8)s(-1). The correlation between -logkf and CTP is much improved than using previously published contact order (CO) method. It has been further suggested that short sequence separations may be preferred for the establishment of stable interactions for the design of novel artificial enzymes and the modification of slow-folding proteins with aggregating intermediates.  相似文献   
996.
We analyze models of evolution of sex ratio conditional on habitat quality and with sex specific dispersal. Previous analysis concluded that the main constraint on sex ratio is habitat choice and leads to overproduction of the most dispersing sex in low quality habitat. Here, we analyze three models with finite local populations and show that constraints on sex ratio can balance constraints on habitat choice. In the first model, dispersal rates are fixed. In the second, sex specific dispersal can evolve independently of the habitat quality. These models suggests that sex ratio evolution can lead to higher global dispersal rates (mean of male and female dispersal rates) from high quality habitats. In the last model dispersal evolves conditionally with both sex and habitat. Our models suggests that conditions for overproduction of the most dispersing sex in high quality habitat are frequent. The predictions of the models with evolving dispersal contrast with patterns generally described in nature. We discuss possible reasons of this difference.  相似文献   
997.
Based on high-resolution structures of the free molecules accurate determination of structures of protein complexes by NMR spectroscopy is possible using residual dipolar couplings. In order, however, to be able to apply these methods, protein backbone resonances have to be assigned first. This NMR assignment process is particularly difficult and time consuming for protein sizes above 20 kDa. Here we show that, when NMR resonances belonging to a specific amino acid type are selected either by amino acid specific labeling, by their characteristic C/C chemical shifts or by dedicated NMR experiments, molecular alignment tensors of proteins up to 80 kDa can be determined without prior backbone resonance assignment. This offers the opportunity to greatly accelerate determination of three-dimensional structures of protein-protein and protein-ligand complexes, and validation of multimeric states of proteins. Moreover, exhaustive back-calculation can be performed using only 1DNH couplings. Therefore, it avoids expensive 13C-labeling and it gives access to orientational information for large proteins that strongly aggregate at concentrations above 50 M, i.e., experimental conditions where 3D triple resonance experiments are not sensitive enough to allow backbone resonance assignment.  相似文献   
998.
Pre-fight displays typically provide honest, but sometimes dishonest, information about resource holding potential and may be influenced by assessment of resource value and hence motivation to acquire the resource. These assessments of potential costs and benefits are also predicted to influence escalated fight behaviour. This is examined in shell exchange contests of hermit crabs in which we establish an information asymmetry about a particularly poor quality shell. The poor shell was created by gluing sand to the interior whereas control shells lacked sand and the low value of the poor shell could not be accurately assessed by the opponent. Crabs in the poor shell showed changes in the use of pre-fight displays, apparently to increase the chances of swapping shells. When the fights escalated, crabs in poor shells fought harder if they took the role of attacker but gave up quickly if in the defender role. These tactics appear to be adaptive but do not result in a major shift in the roles taken or outcome. We thus link resource assessment with pre-fight displays, the roles taken, tactics used during escalation and the outcome of these contests.  相似文献   
999.
The formal Darwinism project: a mid-term report   总被引:1,自引:0,他引:1  
For 8 years I have been pursuing in print an ambitious and at times highly technical programme of work, the 'Formal Darwinism Project', whose essence is to underpin and formalize the fitness optimization ideas used by behavioural ecologists, using a new kind of argument linking the mathematics of motion and the mathematics of optimization. The value of the project is to give stronger support to current practices, and at the same time sharpening theoretical ideas and suggesting principled resolutions of some untidy areas, for example, how to define fitness. The aim is also to unify existing free-standing theoretical structures, such as inclusive fitness theory, Evolutionary Stable Strategy (ESS) theory and bet-hedging theory. The 40-year-old misunderstanding over the meaning of fitness optimization between mathematicians and biologists is explained. Most of the elements required for a general theory have now been implemented, but not together in the same framework, and 'general time' remains to be developed and integrated with the other elements to produce a final unified theory of neo-Darwinian natural selection.  相似文献   
1000.
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