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排序方式: 共有2393条查询结果,搜索用时 31 毫秒
31.
Robert Mason Helen C. Dearden Bella Nguyen Jennifer A. Soon Jessica Louise Smith Manreet Randhawa Andrew Mant Lydai Warburton Serigne Lo Tarek Meniawy Alexander Guminski Phillip Parente Sayed Ali Andrew Haydon Georgina V. Long Matteo S. Carlino Michael Millward Victoria G. Atkinson Alexander M. Menzies 《Pigment cell & melanoma research》2020,33(2):358-365
The combination of ipilimumab and nivolumab is a highly active systemic therapy for metastatic melanoma but can cause significant toxicity. We explore the safety and efficacy of this treatment in routine clinical practice, particularly in the setting of serine/threonine‐protein kinase B‐Raf (BRAF)‐targeted therapy. Consecutive patients with unresectable stage IIIC/IV melanoma commenced on ipilimumab and nivolumab across 10 tertiary melanoma institutions in Australia were identified retrospectively. Data collected included demographics, response and survival outcomes. A total of 152 patients were included for analysis, 39% were treatment‐naïve and 22% failed first‐line BRAF/MEK inhibitors. Treatment‐related adverse events occurred in 67% of patients, grade 3–5 in 38%. The overall objective response rate was 41%, 57% in treatment‐naïve and 21% in BRAF/MEK failure patients. Median progression‐free survival was 4.0 months (95% CI, 3.0–6.0) in the whole cohort, 11.0 months (95% CI, 6.0‐NR) in treatment‐naïve and 2.0 months (95% CI, 1.4–4.6) in BRAF/MEK failure patients. The combination of ipilimumab and nivolumab can be used safely and effectively in a real‐world population. While first‐line efficacy appears comparable to trial populations, BRAF‐mutant patients failing prior BRAF/MEK inhibitors show less response. 相似文献
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Florian M. Rossmann Isabelle Hug Matteo Sangermani Urs Jenal Morgan Beeby 《Molecular microbiology》2020,114(3):443-453
Bacterial flagellar motility is controlled by the binding of CheY proteins to the cytoplasmic switch complex of the flagellar motor, resulting in changes in swimming speed or direction. Despite its importance for motor function, structural information about the interaction between effector proteins and the motor are scarce. To address this gap in knowledge, we used electron cryotomography and subtomogram averaging to visualize such interactions inside Caulobacter crescentus cells. In C. crescentus, several CheY homologs regulate motor function for different aspects of the bacterial lifestyle. We used subtomogram averaging to image binding of the CheY family protein CleD to the cytoplasmic Cring switch complex, the control center of the flagellar motor. This unambiguously confirmed the orientation of the motor switch protein FliM and the binding of a member of the CheY protein family to the outside rim of the C ring. We also uncovered previously unknown structural elaborations of the alphaproteobacterial flagellar motor, including two novel periplasmic ring structures, and the stator ring harboring eleven stator units, adding to our growing catalog of bacterial flagellar diversity. 相似文献
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Langeneck Joachim Englezou Chris Di Maggio Matteo Castelli Alberto Maltagliati Ferruccio 《Hydrobiologia》2021,848(17):4093-4114
Hydrobiologia - Aphanius fasciatus is a small fish occurring in Mediterranean brackish environments. In Cyprus it is known from three localities separated by long stretches of coast. The genetic... 相似文献
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Cazzanelli Matteo Soria-Barreto Miriam Castillo María Mercedes Rodiles-Hernández Rocío 《Hydrobiologia》2021,848(4):773-797
Hydrobiologia - Floodplains are some of the most productive and diverse ecosystems on Earth. The Usumacinta River Basin, in the Southern Gulf of Mexico, hosts several floodplain lakes, whose... 相似文献
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John A. Kloetzel Anne Aubusson-Fleury Maurice D. Butler Deben Banerjee Matteo Mozzicafreddo 《The Journal of eukaryotic microbiology》2021,68(3):e12850
In the hypotrich ciliate Euplotes, many individual basal bodies are grouped together in tightly packed clusters, forming ventral polykinetids. These groups of basal bodies (which produce compound ciliary organelles such as cirri and oral membranelles) are cross-linked into ordered arrays by scaffold structures known as “basal-body cages.” The major protein comprising Euplotes cages has been previously identified and termed “cagein.” Screening a E. aediculatus cDNA expression library with anti-cagein antisera identified a DNA insert containing most of a putative cagein gene; standard PCR techniques were used to complete the sequence. Probes designed from this gene identified a macronuclear “nanochromosome” of ca. 1.5 kb in Southern blots against whole-cell DNA. The protein derived from this sequence (463 residues) is predicted to be hydrophilic and highly charged; however, the native cage structures are highly resistant to salt/detergent extraction. This insolubility could be explained by the coiled-coil regions predicted to extend over much of the length of the derived cagein polypeptide. One frameshift sequence is found within the gene, as well as a short intron. BLAST searches find many ciliates with evident homologues to cagein within their derived genomic sequences. 相似文献
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Umberto Nicosia Fabio Massimo Petti Gianluca Perugini Simone D’Orazi Porchetti Eva Sacchi Maria Alessandra Conti 《Ichnos》2013,20(1-2):69-90
A really unexpected finding of sauropod and theropod footprints in southern Latium raises to four the number of the trampled levels recognized in central and southern Italy. After the recent findings in Latest Jurassic and Early, mid and Late Cretaceous carbonate platform deposits of the Periadriatic region, dinosaur footprints seem to provide very important paleogeographic constraints for reconstructing the geodynamic history of the Mediterranean area. The presence of a varied ichnoassociation makes acceptance of the current paleogeographic models concerning the relative and absolute position of the Laziale-Abruzzese-Campano and of Apulian-Dinaric domains during the Late Cretaceous more and more problematic. Dinosaur footprints, combined with other paleontological data, demonstrate that these areas were never completely pulled apart by deep seaways, while frequent or continuous links between them, and to southern and northern mainlands, probably persisted. These data also allowed us to improve our understanding of the timing of the Mesozoic plate motion in this segment of the Western Tethys. 相似文献
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When a fossil vanishes to a private collection, it must be considered lost to science because, frequently, it is no longer available for study. Fortunately some fossils occasionally are regained. We had the opportunity to recoup an interesting footprint-bearing slab that was part of a private collection in Italy. The specimen, found in 1992 near Seligman, Arizona (USA) was described, before disappearing, as one of the best fossil examples of vertebrate (Chelichnus [Laoporus])-on-invertebrate (Octopodichnus) predation. After a careful re-examination of the slab, the primary conclusions of the former describers are demonstrably groundless. The reanalysis of the tracks, as well as peculiar sedimentary structures associated with the tracks, allowed obtaining new information about the depositional environment and the complex interactions between the type of substrate and trackmaker behavior. The re-examination of the specimen also revealed interesting aspects about trackmaker biomechanics. 相似文献