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991.
992.
Rolf G. Beutel Dominique Zimmermann Marcus Krauß Susanne Randolf Benjamin Wipfler 《Organisms Diversity & Evolution》2010,10(4):311-329
External and internal head structures of Osmylus fulvicephalus were examined and described in detail. Exo- and endoskeleton, musculature, elements of the central nervous system and tracheae
are compared to conditions found in other groups of Neuropterida and other endopterygote lineages. Thirty-six adult cephalic
characters were compiled, combined in a datamatrix with 64 characters of the larval head, and analysed cladistically. Mainly
because many data on adults remain missing, most branches in the cladogram are mostly or exclusively supported by larval features.
The shortening of the mesal mandibular wall and the resulting anterior shift of the adductor tendon possibly constitute an
adult groundplan apomorphy of Neuropterida. Raphidioptera and Megaloptera share distinct prognathism and the presence of a
sclerotised gula. However, the orthognathous head and the absence of a gula resulted as autapomorphies of Neuroptera in our
analyses. Further potential autapomorphies are the asymmetry of the mandibles as well as the respective presence of dorsolateral
furrows on the head capsule, of a shovel-like extension on the ventral mandibular cutting edge, and of a row of stiff hairs
on the mandible’s ventral surface. The systematic affinities of Osmylidae remain ambiguous. Osmylus is mainly characterised by plesiomorphic features of the adult head such as a complete endoskeleton, long filiform antennae,
largely unmodified orthopteroid mouthparts, and particularly the nearly complete set of muscles. The placement with a clade
also comprising Hemerobiidae and Chrysopidae is poorly supported. The presence of a dense vestiture of long microtrichia on
the distal galeomere resulted as a synapomorphy of the three families. An apparent plesiomorphy preserved in Osmylus but absent in all other groups of Neuroptera is the presence of well developed ocelli. The present study underlines the severe
shortage of detailed morphological data on the adults. Intensive study of adult structures is required for a solid reconstruction
of the phylogeny of Neuropterida, especially of the hemerobiform lineage of Neuroptera. 相似文献
993.
994.
Repeated applications of Cydia pomonella granulovirus (CpGV) can effectively control the codling moth (CM) in apple orchards. However, it is still unknown whether horizontal transmission of the virus from infected to uninfected larvae contributes to the efficacy of the virus insecticide. Horizontal transmission of CpGV was assayed using detached apples. In experiments using artificially applied virus dots on the apple’s surface or infected CM larvae as virus inoculum, it was found that the likelihood of infection of healthy CM larvae relied mainly on the larval behavior. The amount of virus inoculum, either applied artificially or produced by the infected larvae, impacted the infection rate only to a small degree. In the experiments, CM larvae exhibited a strong preference in entry sites, increasing the chance for horizontal transmission. Depending on the experimental design, horizontal transmission rates of about 40% were observed in laboratory assays. 相似文献
995.
996.
The flagellate Euglena gracilis Klebs strain Z shows phototaxis and changes cell shape between oblong and round. Both cell events show daily rhythmicity. Phototaxis was highest about 2 h after light onset with a second peak of activity 9 h later. At the same times, the cells were in their most oblong shape. During the night phase the cells were phototactically inactive and round. These rhythms were altered by environmental stress, e.g. UV-B radiation (280–320 nm) and nitrogen deficiency. Artificial UV-B radiation of 0.5 W m−2 caused a loss in phototaxis hut the peak of activity occurred at the same time as for control cells. The transition from round to oblong cell shape was slower after UV-B radiation, but the difference between the roundest and the most oblong cell shape was unchanged. Nitrogen deficiency caused a total loss of phototaxis and the cells remained round all the time. The cells lost all their chlorophyll and were, therefore, photosynthetically inactive. 相似文献
997.
998.
Harald Carlsen Fred Haugen Susanne Zadelaar Robert Kleemann Teake Kooistra Christian A. Drevon Rune Blomhoff 《Genes & nutrition》2009,4(3):215-222
The nuclear factor (NF)-κB is a primary regulator of inflammatory responses and may be linked to pathology associated with obesity. We investigated the progression of NF-κB activity during a 12-week feeding period on a high-fat diet (HFD) or a low-fat diet (LFD) using NF-κB luciferase reporter mice. In vivo imaging of luciferase activity showed that NF-κB activity was higher in the HFD mice compared with LFD-fed mice. Thorax region of HFD females displayed fourfold higher activity compared with LFD females, while no such increase was evident in males. In male HFD mice, abdominal NF-κB activity was increased twofold compared with the LFD males, while females had unchanged NF-κB activity in the abdomen by HFD. HFD males, but not females, exhibited evident glucose intolerance during the study. In conclusion, HFD increased NF-κB activity in both female and male mice. However, HFD differentially increased activity in males and females. The moderate increase in abdomen of male mice may be linked to glucose intolerance. 相似文献
999.
Sputum smear microscopy is widely used for tuberculosis diagnosis and treatment monitoring. We evaluated the correlation between smear microscopy and time to liquid culture positivity during early tuberculosis treatment. The study included patients with smear-positive pulmonary tuberculosis hospitalized at a tuberculosis reference centre in Germany between 01/2012 and 05/2013. Patient records were reviewed and clinical, radiological and microbiological data were analysed. Sputum samples were collected before treatment initiation and weekly thereafter. A number of 310 sputum samples from 30 patients were analysed. Time to liquid culture positivity inversely correlated with smear grade (Spearman''s rho −0.439, p<0.001). There was a better correlation within the first two months vs. after two months of therapy (−0.519 vs. −0.416) with a trend to a more rapid increase in time to positivity between baseline and week 2 in patients who culture-converted within the first two months (5.9 days vs. 9.4 days, p = 0.3). In conclusion, the numbers of acid-fast bacilli in sputum smears of patients with pulmonary tuberculosis and time to culture positivity for M. tuberculosis cultures from sputum are correlated before and during tuberculosis treatment. A considerable proportion of patients with culture conversion after two months of therapy continued to have detectable acid-fast bacilli on sputum smears. 相似文献
1000.
Roland Dürr Reiner Hegerl Susanne Volker Ute Santarius Wolfgang Baumeister 《Journal of structural biology》1991,106(3)
The three-dimensional structure of the surface layer protein of the hyperthermophilic archaebacterium Pyrodictium brockii was determined by electron crystallographic techniques to a resolution of approximately 1.6 nm. Two image processing strategies—correlation averaging and lattice unbending—were explored with regard to their potential to compensate for lattice distortions. Reconstructions performed via these two routes did not show any significant difference although the unbending approach might be expected to give superior results since, in principle, it incorporates a correction for unit cell displacement, rotation, and deformation while conventional correlation averaging compensates for displacements only. The discussion furthermore addresses some hitherto ignored problems associated with the correction of lattice disorder at higher tilts. 相似文献