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71.
目的:研究支原体肺炎(MP)患者血清肺表面活性蛋白-A(SP-A)、肺表面活性蛋白-D(SP-D)与超敏C反应蛋白(hs-CRP)的变化趋势及临床意义。方法:选择从2015年9月到2016年9月在我院治疗的MP患者56例纳入本次研究,将其记为观察组,给予常规治疗后,有效者49例,无效者7例。另选同期在我院进行健康体检的志愿者55例作为对照组,对比两组血清SP-A、SP-D及hs-CRP的变化趋势,比较观察组不同治疗结果患者的血清SP-A、SP-D及hs-CRP水平,并分析患者的血清SP-A、SP-D与hs-CRP的相关性。结果:治疗后3d及治疗后7d观察组的血清SP-A、SP-D及hs-CRP水平较治疗前依次降低,但均高于对照组(P0.05),在治疗后14d血清SP-A、SP-D及hs-CRP水平较治疗前降低(P0.05),但与对照组比较差异无统计学意义(P0.05)。治疗后14 d有效组血清SP-A、SP-D及hs-CRP水平均明显低于无效组,差异有统计学意义(P0.05)。根据Spearman相关性分析结果显示,MP患者的血清SP-A、SP-D与hs-CRP均呈正相关(r=0.713、0.699,P=0.000、0.000)。结论:MP患者的血清SP-A、SP-D及hs-CRP水平可伴随治疗过程的进行而逐渐回落,最终基本恢复至正常范围,且血清SP-A、SP-D水平与hs-CRP水平呈正相关,临床治疗时可针对上述3种指标进行监测以判断患者病情及治疗效果。  相似文献   
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本文报道了采自鄂西晚三叠世地层中的五种种子蕨植物,它们分别隶属于副镰羽叶(Paradrepanozamites)、丁菲羊齿(Thinnfeldia)和篦羽羊齿(Ctenozamites)三个属。由于这些植物的小羽片或羽片基部上边均明显收缩,基部下边均显著下延等,认为它们在系统发生上可能有密切的亲缘关系,并提出它们的形态结构可能朝两个方向发展:一是输导组织不断发达——叶脉从亚放射状,无中脉→有中脉但不发达→中脉发达→变成末级羽轴;二是小羽片或羽片由全缘→局部分裂→大部分裂→羽状全裂。同时,根据奇特篦羽羊齿(新种)[Ctenoza-mites difformis(sp.nov.)]同一植株上的叶呈现四种不同的形态和脉序,初步推测上述三属的演变趋势是:由 Paradrepanozamites→Thinnfeldia→Ctenozamites。  相似文献   
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Effective peptidomimetics should posses structural rigidity and appropriate interaction pattern leading to potential spatial and electronic matching to the target receptor site. Rational design of such small bioactive molecules could push chemical synthesis and molecular modeling toward faster progress in medicinal chemistry. Conformational properties of N‐t‐butoxycarbonyl‐glycine‐(E/Z)‐dehydrophenylalanine N′,N′‐dimethylamides (Boc‐Gly‐(E/Z)‐ΔPhe‐NMe2) in chloroform were studied by NMR and IR spectroscopy. The experimental findings were supported by extensive calculations at DFT(B3LYP, M06‐2X) and MP2 levels of theory and the β‐turn tendency for both isomers of the studied dipeptide were determined in vacuum and in solution. The theoretical data and experimental IR results were used as an additional information for the NMR‐based determination of the detailed solution conformations of the peptides. The obtained results reveal that N‐methylation of C‐terminal amide group changes dramatically the conformational properties of studied dehydropeptides. Theoretical conformational analysis reveals that the tendency to adopt β‐turn conformations is much weaker for the N‐methylated Z isomer (Boc‐Gly‐(Z)‐ΔPhe‐NMe2), both in vacuum and in polar environment. On the contrary, N‐methylated E isomer (Boc‐Gly‐(E)‐ΔPhe‐NMe2) can easily adopt β‐turn conformation, but the backbone torsion angles (φ1, ψ1, φ2, ψ2) are off the limits for common β‐turn types. © 2013 Wiley Periodicals, Inc. Biopolymers 101: 28–40, 2014.  相似文献   
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杭州市螫人胡蜂种类及发生趋势分析   总被引:2,自引:0,他引:2  
对杭州市消防部门2001~2004年为民摘除“马蜂窝”服务情况进行了调查,鉴定出螫人胡蜂有3种:墨胸胡蜂Vespa velutina nigrithoraxBuysson、拟大胡蜂Vespa analis nigransBuysson和亚非马蜂Polistesolivaceus(De Geer),其中墨胸胡蜂为主要危害种类,占所采集蜂巢的77.4%。从不同年份和月份、不同消防区摘除蜂巢服务资料统计结果看出,近年来胡蜂的发生数量呈上升趋势,每年6~10月份为高发期,城市中心区域是蜂巢的主要分布区,居民住宅是主要分布场所。并就治理方法进行了讨论。  相似文献   
78.
The predatory mite Neoseiulus womersleyi shows a significant correlation between its olfactory response and dispersal tendency in different geographical populations. This study investigated the genetic background of the relationship using isofemale lines. Y-tube olfactometer tests confirmed that there was a genetic component in predator response to herbivore-induced plant volatiles. Wind tunnel tests in the absence of the herbivore-induced plant volatiles revealed that the dispersal tendencies of N. womersleyi exhibited genetic variation among isofemale lines, and other experiments revealed the existence of significant differences in prey consumption rate, fecundity, and developmental time. However, there was no genetic correlation between behavioral traits (olfactory response, innate dispersal) and the other traits, suggesting that the positive correlation between the behavioral traits was not caused by genetic factors.  相似文献   
79.
Direct physical chemistry measurements of the hydrophobicity of amino acids or their derivatives have often been used to estimate the propensity of amino acids to participate in transmembrane helices. In this short note, it is found that there is a very high degree of correlation (r = 0.944–0.965) between an average physical chemistry hydrophobicity scale (an average of scales derived, e.g., from the solubility of amino acid derivatives in organic solvents versus water or their binding to hydrophobic particles) and the statistically based transmembrane tendency scale (derived from the relative abundance of residues in known transmembrane and soluble protein sequences (Zhao and London, Protein Sci 15:1987–2001, 2006)). This correlation indicates that, other than hydrophobicity, amino acid properties/interactions that promote or inhibit transmembrane helix formation in a specific membrane protein largely cancel out when averaged over all transmembrane sequences. In other words, other than hydrophobicity, there are no properties of a specific amino acid residue within a hydrophobic segment that have a strong systematic effect upon transmembrane helix formation independent of the remainder of the sequence in that hydrophobic segment. However, proline is an exception to this rule.  相似文献   
80.
The Texas shiner Notropis amabilis and the blacktail shiner Cyprinella venusta demonstrated statistically significant preferences for the side of the tank holding their familiar shoalmates, and significantly stronger shoaling behaviour with their familiar shoalmates, than with unfamiliar fish.  相似文献   
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