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941.
Jean-Claude Brouet Jean-Louis Preud'homme Maxime Seligmann Jean Bernard 《BMJ (Clinical research ed.)》1973,4(5883):23-24
Acute blast crisis occurred in two patients with previously well-confirmed chronic lymphocytic leukaemia. The finding by direct immunofluorescence of membrane-bound monoclonal immunoglobulins on the surface of the blast cells showed that they were related to B cells in the same way as the proliferating lymphocytes in most patients with chronic lymphocytic leukaemia. In one patient the surface monoclonal IgM detected on both the lymphocytes and the blast cells had the same rheumatoid antibody activity, supporting the concept that the leukaemic cells found during the acute and chronic phases of the disease originated from the same clone. 相似文献
942.
Summary
Olpidiopsis antithamnionis n. sp. (Oomycetes, Olpidiopsidaceae) parasitic on Antithamnion floccosum (O. F. Müll.) Kleen (Rhodophyta, Ceramiaceae) is described from three sites in Newfoundland, Canada, and from culture.Axial cells of the main and determinate branches of the host are the primary sites of fungal attack, although tetrasporangia and rhizoidal cells are also susceptible. Successful re-infection of A. floccosum was achieved in the laboratory although A. boreale and the trailliella-phase of Bonnemaisonia hamifera, both occurring with A. floccosum in the field, were immune. Regeneration of the host cells was observed, a phenomenon not previously reported in the fungal parasitism of other filamentous benthic marine algae.Studies in Biology from Memorial University of Newfoundland No. 256. 相似文献
943.
Robin D. Veldsema-Currie 《The Biochemical journal》1973,135(4):673-682
1. An enzyme similar to mammalian acetylcholinesterase is found in high activity in the nervous tissue of Palaemonetes varians, i.e. eyes plus stalks, brain, suboesophageal ganglion and ventral cord. Acetylcholinesterase is also found associated with the abdominal muscles. Multiple enzyme forms are found in extracts of nervous tissues and muscles by electrophoresis and isoelectric focusing. 2. Cholinesterase is present in high activity in the stomatogastric system of P. varians. Three electrophoretically separable forms are found, having isoelectric points at pH4.2, 4.5 and 5.4. 3. Approx. 50% of the total acetylcholinesterase activity, approx. 80% of the choline acetyltransferase activity and 100% of the acetylcholine equivalents are found associated with the nervous tissue. Among the tissues examined, eyes plus stalks were the richest source of both choline acetyltransferase and acetylcholine equivalents. Suboesophageal ganglion and brain also contained large amounts of these components. 4. The distribution of these components could support the function of acetylcholine as a central and/or sensory transmitter in P. varians. 相似文献
944.
Low-Molecular-Weight RNAs of Murine Sarcoma Virus: Comparative Studies of Free and 70S RNA-Associated Components 总被引:4,自引:4,他引:0
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R. Emanoil-Ravicovitch C. J. Larsen M. Bazilier J. Robin J. Périès M. Boiron 《Journal of virology》1973,12(6):1625-1627
Several low-molecular-weight RNAs were released from mouse leukemia sarcoma virus 70S RNA under conditions of thermal denaturation. One of them, the 70S-associated 8S RNA, exhibits a number of structural properties characteristic of a previously described free viral 8S RNA. This similarity was revealed by polyacrylamide gel electrophoresis and nucleotide composition. 相似文献
945.
946.
Jonas B. Nielsen Lars G. Fritsche Wei Zhou Tanya M. Teslovich Oddgeir L. Holmen Stefan Gustafsson Maiken E. Gabrielsen Ellen M. Schmidt Robin Beaumont Brooke N. Wolford Maoxuan Lin Chad M. Brummett Michael H. Preuss Lena Refsgaard Erwin P. Bottinger Sarah E. Graham Ida Surakka Yunhan Chu Cristen J. Willer 《American journal of human genetics》2018,102(1):103-115
947.
948.
949.
Eric W.M. Stienen Peter Desmet Bart Aelterman Wouter Courtens Simon Feys Nicolas Vanermen Hilbran Verstraete Marc Van de Walle Klaas Deneudt Francisco Hernandez Robin Houthoofdt Bart Vanhoorne Willem Bouten Roland-Jan Buijs Marwa M. Kavelaars Wendt Müller David Herman Hans Matheve Alejandro Sotillo Luc Lens 《ZooKeys》2016,(555):115-124
In this data paper, Bird tracking - GPS tracking of Lesser Black-backed Gulls and Herring Gulls breeding at the southern North Sea coast is described, a species occurrence dataset published by the Research Institute for Nature and Forest (INBO). The dataset (version 5.5) contains close to 2.5 million occurrences, recorded by 101 GPS trackers mounted on 75 Lesser Black-backed Gulls and 26 Herring Gulls breeding at the Belgian and Dutch coast. The trackers were developed by the University of Amsterdam Bird Tracking System (UvA-BiTS, http://www.uva-bits.nl). These automatically record and transmit bird movements, which allows us and others to study their habitat use and migration behaviour in great detail. Our bird tracking network is operational since 2013. It is funded for LifeWatch by the Hercules Foundation and maintained in collaboration with UvA-BiTS and the Flanders Marine Institute (VLIZ). The recorded data are periodically released in bulk as open data (http://dataset.inbo.be/bird-tracking-gull-occurrences), and are also accessible through CartoDB and the Global Biodiversity Information Facility (GBIF). 相似文献
950.
Akiko Shoji Ben Dean Holly Kirk Robin Freeman Christopher M. Perrins Tim Guilford 《Ibis》2016,158(3):598-606
The diving capabilities of the Procellariformes remain the least understood component of avian diving physiology. Due to their relatively small size, shearwaters may have high oxygen consumption rates during diving relative to their available oxygen stores. Dive performance in this group should be strongly limited by the trade‐off between oxygen consumption and oxygen stores, and shearwaters could be a good model group for testing predictions of dive theory. Many earlier measurements of shearwater dive behaviour relied on observations from the surface or potentially biased technology, and it is only recently that diving behaviour has been observed using electronic recorders for many of the clades within the family. The diving behaviour of Manx Shearwaters Puffinus puffinus breeding in Wales, UK, was studied on a large sample of birds using time–depth–temperature recorders deployed on chick‐rearing shearwaters in July and August over 3 years (2009–2011). Light availability apparently limited diving as dives only occurred between 04:00 and 19:00 h GMT. All individuals routinely dived deeper than traditionally assumed, to a mean maximum depth of 31 m and occasionally down to nearly 55 m. We compiled all available data for a comparison of the dive depth across shearwater species. There was a positive allometric relationship between maximum dive depth and body mass across Puffinus and Ardenna shearwater species, as expected, but only if samples of fewer than two individuals were excluded. The large intra‐specific range in maximum dive depth in our study illustrates that apparent diversity in diving performance across species must be interpreted cautiously. 相似文献