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The previously unknown female and larva for the New Zealand glacier midge, Zealandochlus latipalpis Brundin are described for the first time, and the pupa described more fully than previously. Unlike the male, which is brachypterous, the female has large wings possessing traces of a vein between R1 and R4+5 uniquely for the subfamily Podonominae. The larvae, known locally as ice-worms, live in meltwater pools and ice caves of the Franz Joseph and Fox glaciers, New Zealand. Cladistic analysis of this highly autapomorphic species results in an unresolved trichotomy Zelandochlus + Parochlus + Podonomus, which is no advance on the suggestion made by Brundin (1966) concerning the relationships. Information is too scanty on many species of the putative related genera, but additional morphological features indicate that there may be a sister group relationship with part of Parochlus.  相似文献   
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This Phase 1, randomized, two-site (United States), double-blind, placebo-controlled study enrolled 18 sexually abstinent men and women. All received a single 300-mg dose of oral tenofovir disoproxil fumarate (TDF) and were then randomized 2∶1 to receive single and then seven daily rectal exposures of vaginally-formulated tenofovir (TFV) 1% gel or a hydroxyethyl cellulose (HEC) placebo gel. Blood, colonic biopsies and rectal and vaginal mucosal fluids were collected after the single oral TDF, the single topical TFV gel dose, and after 7 days of topical TFV gel dosing for extracellular analysis of TFV and intracellular analysis of the active metabolite tenofovir diphosphate (TFVdp) in peripheral blood mononuclear cells (PBMCs) and isolated mucosal mononuclear cells (MMC), including CD4+ and CD4- cell subsets. With a single rectal dose, TFV plasma concentrations were 24–33 fold lower and half-life was 5 h shorter compared to a single oral dose (p = 0.02). TFVdp concentrations were also undetectable in PBMCs with rectal dosing. Rectal tissue exposure to both TFV and TFVdp was 2 to 4-log10 higher after a single rectal dose compared to a single oral dose, and after 7 daily doses, TFVdp accumulated 4.5 fold in tissue. TFVdp in rectal tissue homogenate was predictive (residual standard error, RSE  = 0.47) of tissue MMC intracellular TFVdp concentration, with the CD4+ cells having a 2-fold higher TFVdp concentration than CD4- cells. TFV concentrations from rectal sponges was a modest surrogate indicator for both rectal tissue TFV and TFVdp (RSE  = 0.67, 0.66, respectively) and plasma TFV (RSE  = 0.38). TFV penetrates into the vaginal cavity after oral and rectal dosing, with rectal dosing leading to higher vaginal TFV concentrations (p<0.01).

Trial Registration

ClinicalTrials.gov NCT00984971  相似文献   
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细胞壁是酵母细胞区别于哺乳动物细胞的重要特征结构。酵母细胞壁的结构组成、合成、再生等与酵母自身繁殖及环境胁迫压力密切相关。目前,酵母孢子壁的形成机理、调控过程机制及孢子壁合成相关基因的功能尚未研究清楚。本文以酿酒酵母为例,简要描述酵母孢子壁的形成过程,重点阐述孢子壁甘露糖层、葡聚糖层、壳聚糖层和二酪氨酸层的结构组成及其合成相关基因的国内外研究进展,以期为抗真菌药物的新靶点研究提供参考。  相似文献   
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Abstract All life-history stages of the Australian Podonominae (Chironomidae) genus Archaeochlus Brundin are revised, providing evidence for recognition of a separate clade, named here as Austrochlus Cranston. Based on molecular and morphological evidence, the clade contains two additional species: Austrochlus parabrundini Cranston, Edward and Cook sp. n. is described from Western Australia where its granite outcrop seepage habitat and geographical range is almost identical to that of the type species Austrochlus brundini Cranston, Edward and Colless (n. comb); Austrochlus centralaustralis Cranston, Edward and Cook sp. n. is described from ephemeral seepage/flows in the MacDonnell and James Ranges of central Australia. Molecular studies reported here confirm species distinctions, relationships to African taxa, and basal relationships within the Chironomidae. Modelled distributions provide evidence for range restriction by seasonal rainfall patterns.  相似文献   
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Background  

Identification of DNA-binding proteins is one of the major challenges in the field of genome annotation, as these proteins play a crucial role in gene-regulation. In this paper, we developed various SVM modules for predicting DNA-binding domains and proteins. All models were trained and tested on multiple datasets of non-redundant proteins.  相似文献   
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