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The various classifications of the orchid tribeNeottieae are reviewed and a new classification is proposed that divides the tribe into three subtribes,Neottiinae, Limodorinae, andCephalantherinae, based primarily on characters of the column (gynostemium). A cladistic analysis illustrates that these three subtribes are more closely related to one another than either is to any other group in subfam.Neottioideae, although there are very few apomorphic characters for the tribe. Pollination biology is also discussed showing links between breeding systems and distribution. There is also a possible role between column and labellum morphology and the emergence of a deceptive pollination syndrome from one of reward.  相似文献   
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The COVID‐19 pandemic has triggered numerous scientific activities aimed at understanding the SARS‐CoV‐2 virus and ultimately developing treatments. Structural biologists have already determined hundreds of experimental X‐ray, cryo‐EM, and NMR structures of proteins and nucleic acids related to this coronavirus, and this number is still growing. To help biomedical researchers, who may not necessarily be experts in structural biology, navigate through the flood of structural models, we have created an online resource, covid19.bioreproducibility.org, that aggregates expert‐verified information about SARS‐CoV‐2‐related macromolecular models. In this article, we describe this web resource along with the suite of tools and methodologies used for assessing the structures presented therein.  相似文献   
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The aim of the study was to evaluate changes in hamstring flexibility in 120 asymptomatic children who participated in a 6-week program consisting of one physiotherapy session per week and daily home exercises. The recruitment criteria included age (10–13 years), no pain, injury or musculoskeletal disorder throughout the previous year, physical activity limited to school sport. Subjects were randomly assigned to one of the three groups: (1) post-isometric relaxation – PIR (n = 40), (2) static stretch combined with stabilizing exercises – SS (n = 40) and (3) stabilizing exercises – SE (n = 40). Hamstring flexibility was assessed with straight leg raise (SLR), popliteal angle (PA) and finger-to-floor (FTF) tests. The examinations were conducted by blinded observers twice, prior to the program and a week after the last session with the physiotherapist. Twenty-six children who did not participate in all six exercise sessions with physiotherapists were excluded from the analysis. The results obtained by 94 children were analyzed (PIR, n = 32; SS, n = 31; SE, n = 31). In the PIR and SS groups, a significant (P<0.01) increase in SLR, PA, FTF results was observed. In the SE group, a significant (P<0.001) increase was observed in the SLR but not in the PA and FTF (P>0.05). SLR result in the PIR and SS groups was significantly (P<0.001) higher than in the SE group. As far as PA results are concerned, a significant difference was observed only between the SS and SE groups (P = 0.014). There were no significant (P = 0.15) differences regarding FTF results between the three groups. Post-isometric muscle relaxation and static stretch with stabilizing exercises led to a similar increase in hamstring flexibility and trunk forward bend in healthy 10–13-year-old children. The exercises limited to straightening gluteus maximus improved the SLR result, but did not change the PA and FTF results.  相似文献   
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Many studies have investigated how different variables influence the reproductive success (RS) in the populations of natural birth control. Here, we tested hypotheses about positive relationship between wealth, height and several measures of RS in an indigenous, traditional society from West Papua. The study was conducted among the Yali tribe in a few small, isolated mountain villages. In this tribe, a man's wealth is measured by the number of pigs he possesses. We found that wealth was related to fertility and number of living children, but not to child mortality in both men and women. Additionally, child mortality increased with the number of children in a family. Finally, we did not observe any relationship between height and reproductive success measures or wealth. We provide several possible explanations of our results and also put forward hypothetical background for further studies of indigenous populations.  相似文献   
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Biological Trace Element Research - Intermitted fasting or every-other-day feeding (EOD) has many positive effects in rodents and humans. Our goal was to describe how EOD influences bone mineral...  相似文献   
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CD36 is a fatty acid translocase in striated muscle cells and cardiomyocytes. Some study suggested that alterations in CD36 gene may be associated with coronary artery disease (CAD) risk. The aim of the current study was to compare the frequency of CD36 variants in region encoding lipid-binding domain in Caucasian patients with early-onset CAD, no-CAD adult controls and neonates. The study group comprised 100 patients with early onset CAD. The genetic control groups were 306 infants and 40 no-CAD adults aged over 70 years. Exons 4, 5 and 6 including fragments of flanking introns were studied using the denaturing high-performance liquid chromatography technique and direct sequencing. Changes detected in analyzed fragment of CD36: IVS3-6 T/C (rs3173798), IVS4-10 G/A (rs3211892), C311T (Thr104Ile, not described so far) in exon 5, G550A (Asp184Asn, rs138897347), C572T (Pro191Leu, rs143150225), G573A (Pro191Pro, rs5956) and A591T (Thr197Thr, rs141680676) in exon 6. No significant differences in the CD36 genotype, allele and haplotype frequencies were found between the three groups. Only borderline differences (p = 0.066) were found between early onset CAD patients and newborns in the frequencies of 591T allele (2.00% vs 0.50%) and CGCGCGT haplotype (2.00% vs 0.50%) with both IVS3-6C and 591T variant alleles. In conclusion, CD36 variants: rs3173798, rs3211892, rs138897347, rs5956, rs143150225 rs141680676 and C311T do not seem to be involved in the risk of early-onset CAD in Caucasian population.  相似文献   
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