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1.
Aim The geological evolution of the Mediterranean region is largely the result of the Tertiary collision of the African and Eurasian Plates, but also a mosaic of migrating island arcs, fragmenting tectonic belts, and extending back‐arc basins. Such complex paleogeography has resulted in a ‘reticulate’ biogeographical history, in which Mediterranean biotas repeatedly fragmented and merged as dispersal barriers appeared and disappeared through time. In this study, dispersal‐vicariance analysis (DIVA) is used to assess the relative role played by dispersal and vicariance in shaping distribution patterns in the beetle subfamily Pachydeminae Reitter, 1902 (Scarabaeoidea), an example of east–west Mediterranean disjunction. Location The Mediterranean region, including North Africa, the western Mediterranean, Balkans–Anatolia, Middle East, Caucasus, the Iranian Plateau, and Central Asia. Methods A phylogenetic hypothesis of the Palearctic genera of Pachydeminae in conjunction with distributional data was analysed using DIVA. This method reconstructs the ancestral distribution in a given phylogeny based on the vicariance model, while allowing dispersal and extinction to occur. Unlike other methods, DIVA does not enforce area relationships to conform to a hierarchical ‘area cladogram’, so it can be used to reconstruct ‘reticulate’ biogeographical scenarios. Results Optimal reconstructions, requiring 23 dispersal events, suggest that the ancestor of Pachydeminae was originally present in the south‐east Mediterranean region. Basal splitting within the subfamily was caused by vicariance events related to the late Tertiary collision of the African microplates Apulia and Arabia with Eurasia, and the resultant arise of successive dispersal barriers (e.g. the Red Sea, the Zagros Mountains). Subsequent diversification in Pachydeminae involved multiple speciation events within the Middle East and Iran–Afghanistan regions, which gave rise to the least speciose genera of Pachydeminae (e.g. Otoclinius Brenske, 1896). Finally, the presence of Pachydeminae in the western Mediterranean region seems to be the result of a recent dispersal event. The ancestor of the Iberian genera Ceramida Baraud, 1987 and Elaphocera Gené, 1836 probably dispersed from the Middle East to the Iberian Peninsula across North Africa and the Gibraltar Strait during the ‘Messinian salinity crisis’ at the end of the Miocene. Main conclusions Although the basal diversification of Pachydeminae around the Mediterranean appears to be related to vicariance events linked to the geological formation of the Mediterranean Basin, dispersal has also played a very important role. Nearly 38% of the speciation events in the phylogeny resulted from dispersal to a new area followed by allopatric speciation between lineages. Relationships between western and eastern Mediterranean disjuncts are usually explained by dispersal through Central Europe. The biogeographical history of the Pachydeminae corroborates other biogeographical studies that consider North Africa to be an alternative dispersal route by which Mediterranean taxa could have achieved circum‐Mediterranean distributions.  相似文献   
2.
The mechanism of mass collaboration in risk management was studied during the Sichuan earthquake under a Web-based “PeopleFinder” project, where information is contributed and shared among mass contributors. The case study is provided by a great earthquake that happened in Wenchuan County, Sichuan Province, of southwestern China at 2:28 p.m. on May 12, 2008. We witnessed and experienced the rescue and relief efforts for the great earthquake. In this article, two fundamental frameworks are developed to study the mechanism of mass collaboration. Mass collaboration is proven to be effective in a big public crisis such as the Sichuan earthquake.  相似文献   
3.
It has been known for several decades that cultured murine cells undergo a defined series of changes, i.e., anin vitro evolution, which includes crisis, spontaneous transformation (immortalization), aneuploidy, and spontaneous neoplastic transformation. These changes have been shown to be caused by thein vitro environment rather than an inherent instability of the murine phenotype or genotype. Serum amine oxidases were recently identified as a predominant cause of crisis. These enzymes generate hydrogen peroxide from polyamine substrates that enter the extracellular milieu. This finding implicates free-radical toxicity as the underlying cause ofin vitro evolution. We propose an oxyradical hypothesis to explain each of the stages ofin vitro evolution and discuss its significance for cytotechnology and long-term cultivation of mammalian cell types.ORR, CDER, FDA Mod-1, Room 2023, 8301 Muirkirk Road, Laurel MD 20708, USA  相似文献   
4.
Most anti-nicotinic acetylcholine receptor (AChR) antibodies in myasthenia gravis are directed against an immunodominant epitope or epitopes [main immunogenic region (MIR)] on the AChR alpha-subunit. Thirty-two synthetic peptides, corresponding to the complete Torpedo alpha-subunit sequence and to a segment of human muscle alpha-subunit, were used to map the epitopes for 11 monoclonal antibodies (mAbs) directed against the Torpedo and/or the human MIR and for a panel of anti-AChR mAbs directed against epitopes on the alpha-subunit other than the MIR. A main constituent loop of the MIR was localized within residues alpha 67-76. Residues 70 and 75, which are different in the Torpedo and human alpha-subunits, seem to be crucial in determining the binding profile for several mAbs whose binding to the peptides correlated very well with their binding pattern to native Torpedo and human AChRs. This strongly supports the identification of the peptide loop alpha 67-76 as the actual location of the MIR on the intact AChR molecule. Residues 75 and 76 were necessary for binding of some mAbs and irrelevant for others, in agreement with earlier suggestions that the MIR comprises overlapping epitopes. Structural predictions for the sequence segment alpha 67-76 indicate that this segment has a relatively high segmental mobility and a very strong turning potential centered around residues 68-71. The most stable structure predicted for this segment, in both the Torpedo and human alpha-subunits, is a hairpin loop, whose apex is a type I beta-turn and whose arms are beta-strands. This loop is highly hydrophilic, and its apex is negatively charged. All these structural properties have been proposed as characteristic of antibody binding sites. We also localized the epitopes for mAbs against non-MIR regions. Among these, the epitope for a monoclonal antibody (mAb 13) that noncompetitively inhibits channel function was localized within residues alpha 331-351.  相似文献   
5.
A look into the associations of socioeconomic status (SES) with prevalence of various complications in sickle cell disease (SCD) is necessary, for an improvement of societal norms, governmental health policies and strategies. We therefore studied the influence of SES indices on certain hematological and clinical parameters in children with SCD in Saudi Arabia. We included 32 female and 33 male patients aged 5–16 years, who were classified based upon their family income. Family monthly income was divided into 4 categories from lowest to highest, with socioeconomic class1 having low earnings of <5000 SAR; the middle income class divided further into class 2 with earnings >5000–10,000 SAR, and class 3 with earnings >10,000–15,000 SAR; and the higher income class 4 with earnings of >15,000 SAR. The assessment indices used were, the frequency of vaso-occlusive crisis (VOC), adverse events, and hematological parameters. A higher percentage of children affected with the disease were from class1, which is the low socio-economic class. It was found that the percentage of frequency of VOC pain crisis, and adverse events was higher in social class 1 patients than in the classes 2, 3, and 4. Also, the age group 5–10 years appeared more susceptible to adverse events and VOC. Our findings suggest the need to conduct future larger studies, to deduce the modifying influence of disparity in SES on certain clinical and hematological indices in children with SCD.  相似文献   
6.
摘要 目的:探讨股前外侧穿支皮瓣与胸腹带蒂皮瓣对手外伤组织缺损修复的应用效果及对创面愈合程度的影响。方法:选取我院2018年12月到2020年12月共收治的119例手外伤组织缺损患者作为研究对象,随机分为2组,分别为对照组(n=59,应用胸腹带蒂皮瓣修复术)和观察组(n=60,应用股前外侧穿支皮瓣修复术)。对比两组患者治疗优良率,对比两组患者治疗前后手部创面面积、创面愈合程度以及组织愈合时间,对比两组患者治疗后的Jamar握力、TAM和DASH评分情况,对比两组患者的皮瓣成活率、皮瓣危象率和血管吻合时间。结果:通过对比两组患者治疗优良率发现,观察组患者优的人数为21例、良为35例,优良率为93.33%,对照组患者优的人数为16例,良为30例,优良率为77.97%,观察组高于对照组(P<0.05);治疗后,与对照组相比,观察组患者的手部创面面积、组织愈合时间和DASH评分显著减少,创面愈合程度以及TAM与Jamar握力显著增加(P<0.05);通过对比两组患者的皮瓣成活率、术后皮瓣危象率以及血管吻合时间发现,两组患者的术后皮瓣危象率、血管吻合时间对比无明显差异(P>0.05),两组患者的术后皮瓣成活率对比差异显著,观察组明显高于对照组(P<0.05)。结论:对手外伤组织缺损患者应用股前外侧穿支皮瓣与胸腹带蒂皮瓣修复术均具有明显的修复效果,但是应用股前外侧穿支皮瓣能够提升治疗效果,提升患者创面愈合程度减少愈合时间,提升患者手部运动情况,提升术后皮瓣成活率,值得临床应用推广。  相似文献   
7.
Organophosphate (OP) poisoning is still associated with high morbidity and mortality rates, both in resource-poor settings and in well-developed countries. Despite numerous publications dealing with this particular poison, detailed clinical data on more severe overdoses with these agents are relatively sparsely reported. A retrospective study was consequently conducted on 33 patients with OP poisoning admitted to our intensive care unit (ICU) to provide additional data on clinical features. We included moderate to severe poisonings between 2000 and 2012 who required admission to ICU.  相似文献   
8.
目的:探讨激素联合丙种球蛋白治疗小儿重症肌无力的临床疗效及对患儿免疫球蛋白和补体的影响。方法:回顾性分析在我院治疗的70例重症肌无力患儿的临床资料,采用随机序号的方式将其分为观察组和对照组各35例,观察组给予甲泼尼龙联合丙种球蛋白,对照组仅给予甲泼尼龙,观察两组的临床疗效及免疫球蛋白和补体变化情况。结果:观察组总有效率为94.3%明显优于对照组74.3%,两组比较有统计学意义(P〈0.05);观察组症状明显缓解时间(6.55±1.35)d以及总住院天数(17.15±3.65)d较对照组明显缩短,两组比较差异均有统计学意义(P〈0.05)。结论:采用激素联合丙种球蛋白治疗小儿重症肌无力,可以明显改善患者肌无力症状,获得较为满意的临床疗效,值得进一步推广使用。  相似文献   
9.
The financial crisis in Greece is largely impinging on the health and mental health of the population, raising concerns about a potential rise in suicide rates. The aim of this study was to explore changes in suicidal ideation and reported suicide attempts between 2009 and 2011 in a representative sample of the population and in several population subgroups. The socio‐economic predictors of suicidal ideation and suicide attempts in 2011 were also investigated. Two nationwide cross‐sectional telephone surveys were conducted in 2009 and 2011 using the same methodology. A random and representative sample of 2192 and 2256 people, respectively, took part in the surveys. Between 2009 and 2011, there was a substantial increase in the prevalence of suicidal ideation and reported suicide attempts. People suffering from depression, men, married individuals, people experiencing financial strain, people with low interpersonal trust, and individuals with a history of suicide attempts were particularly vulnerable.  相似文献   
10.
目的:探究甲基强的松龙联合中剂量环磷酰胺(CTX)治疗重症肌无力危象(MGC)的临床效果及安全性。方法:选取2012年1月~2015年6月在我院神经内科就诊的MGC患者90例,随机分为对照组(45例)和观察组(45例),对照组患者接受甲基强的松龙治疗,观察组采用甲基强的松龙联合中剂量CTX治疗。比较两组患者的临床疗效及不良反应的发生情况。结果:观察组患者呼吸困难消失时间、吞咽功能恢复时间和肢体无力症状改善时间均明显短于对照组(P0.05);观察组用药7 d内治疗有效率86.7%明显高于对照组(P0.05),肺部感染发生率20%,较对照组显著降低,差异均具有统计学意义(P0.05)。结论:甲基强的松龙联合中剂量CTX可有效提高MGC的治疗效果,促进患者早日康复,且肺部感染的发生率降低。  相似文献   
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