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排序方式: 共有107条查询结果,搜索用时 15 毫秒
81.
Stefanie Heinicke Isabel Ordaz‐Nmeth Jessica Junker Mona E. Bachmann Sergio Marrocoli Erin G. Wessling Dirck Byler Susan M. Cheyne Jenny Desmond Dervla Dowd Maegan Fitzgerald Marc Fourrier Annemarie Goedmakers R. Adriana Hernandez‐Aguilar Annika Hillers Kimberley J. Hockings Sorrel Jones Michael Kaiser Kathelijne Koops Juan M. Lapuente Fiona Maisels Julia Riedel Emilien Terrade Clement G. Tweh Virginie Vergnes Tina Vogt Elizabeth A. Williamson Hjalmar S. Kühl 《American journal of primatology》2021,83(1)
Despite the large body of literature on ape conservation, much of the data needed for evidence‐based conservation decision‐making is still not readily accessible and standardized, rendering cross‐site comparison difficult. To support knowledge synthesis and to complement the IUCN SSC Ape Populations, Environments and Surveys database, we created the A.P.E.S. Wiki ( https://apeswiki.eva.mpg.de ), an open‐access platform providing site‐level information on ape conservation status and context. The aim of this Wiki is to provide information and data about geographical ape locations, to curate information on individuals and organizations active in ape research and conservation, and to act as a tool to support collaboration between conservation practitioners, scientists, and other stakeholders. To illustrate the process and benefits of knowledge synthesis, we used the momentum of the update of the conservation action plan for western chimpanzees (Pan troglodytes verus) and began with this critically endangered taxon. First, we gathered information on 59 sites in West Africa from scientific publications, reports, and online sources. Information was compiled in a standardized format and can thus be summarized using a web scraping approach. We then asked experts working at those sites to review and complement the information (20 sites have been reviewed to date). We demonstrate the utility of the information available through the Wiki, for example, for studying species distribution. Importantly, as an open‐access platform and based on the well‐known wiki layout, the A.P.E.S. Wiki can contribute to direct and interactive information sharing and promote the efforts invested by the ape research and conservation community. The Section on Great Apes and the Section on Small Apes of the IUCN SSC Primate Specialist Group will guide and support the expansion of the platform to all small and great ape taxa. Similar collaborative efforts can contribute to extending knowledge synthesis to all nonhuman primate species. 相似文献
82.
F. Lejeune D. Linard A. Eggermont H. Schraffordt Koops F. Rosenkaimer J. Grain J. Klaase B. Kroon J. Vanderveken P. Schmitz 《Journal of cellular biochemistry》1994,56(1):52-61
Recombinant tumor necrosis factor-alpha (rTNFα) has potent antitumor activity in experimental studies on human tumor xenografts. However, in humans, the administration of rTNFα is hampered by severe systemic side-effects. The maximum tolerated dose range from 350 to 500 mg/m2, which is at least 10-fold less than the efficient dose in animals. Isolation perfusion of the limbs (ILP) allows the delivery of high dose rTNFα in a closed system with acceptable side-effects. A protocol with a triple-drug regimen was based on the reported synergism of rTNFα with chemotherapy, with interferon-y, and with hydperthermia. In melanoma-in-transit metastases (stage IIIA or AB) we obtained a 91% complete response, compared with 52% after ILP with melphalan alone. Release of nanograms levels of TNFα in the systemic circulation was evident but control of this leakage and appropriate intensive care resulted in acceptable toxicity. Angiographic, immunohistological, and immunological studies suggest that the efficacy of this prtocol is due to a dual targeting: rTNFα activates and electively lyses the tumor endothelial cells while melphalan is mainly cytoxic to the tumor cells. ILP with rTNFα appears to be a useful model for studying the biochemotherapy of cancer in man. 相似文献
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85.
Kim Cuddington Z. Tasker Hull Warren J. S. Currie Marten A. Koops 《Theoretical Ecology》2015,8(3):333-347
Mate-finding difficulties in small populations are often postulated to create strong demographic Allee effects that increase the probability of extinction of native species or, similarly, decrease the probability that non-native species will successfully invade. Many species make use of a restricted number of mating locations, detectable from long-distance, that are not selected for habitat reasons (e.g., hilltopping in butterflies). This ‘landmarking’ strategy may specifically address the problem of overcoming mate-finding difficulties. Using a variant of the birthday problem, we demonstrate that populations which locate a restricted number of mate-finding sites using landmark features may have high probability of successful mating even at very low population densities. Therefore, a strong Allee threshold, if it exists, may be very small, and non-native species that make use of this strategy may have a very good chance of population establishment at low density. 相似文献
86.
Rob M de Graaf Isabel Duarte Theo A van Alen Jan WP Kuiper Klaas Schotanus J?rg Rosenberg Martijn A Huynen Johannes HP Hackstein 《BMC evolutionary biology》2009,9(1):287
Background
Hydrogenosomes are organelles that produce molecular hydrogen and ATP. The broad phylogenetic distribution of their hosts suggests that the hydrogenosomes of these organisms evolved several times independently from the mitochondria of aerobic progenitors. Morphology and 18S rRNA phylogeny suggest that the microaerophilic amoeboflagellate Psalteriomonas lanterna, which possesses hydrogenosomes and elusive "modified mitochondria", belongs to the Heterolobosea, a taxon that consists predominantly of aerobic, mitochondriate organisms. This taxon is rather unrelated to taxa with hitherto studied hydrogenosomes. 相似文献87.
Summary A method that allows separation and determination of three enzyme polymorphisms in one polyacrylamide gel is described. Common phenotypes of adenylate kinase, adenosine deaminase and phosphoglucomutase are diagnosed without difficulties. There are small migration differences between PGM isozymes e and d.
(Direktor: Prof. Dr. W. Janssen) 相似文献
Zusammenfassung Es wird eine Methode beschrieben, die Trennung und Darstellung von drei Enzympolymorphismen in einem Polyacrylamid-Gel ermöglicht. Die Normtypen der Adenylatkinase, Adenosindeaminase und Phosphoglucomutase sind zweifelsfrei zu differenzieren. Geringe Wanderungsunterschiede ergeben sich zwischen den Zonen e und d der PGM Isoenzyme.
(Direktor: Prof. Dr. W. Janssen) 相似文献
88.
Kamonpatana M van de Wiel DF Koops W Leenanuruksa D Ngramsuriyaroj C Usanakornkul S 《Theriogenology》1979,11(5):399-409
A preliminary study has been undertaken, in order to investigate the suitability of a progesterone assay in blood plasma for oestrus control and pregnancy diagnosis in the swamp buffalo (Bubalus bubalis ). Progesterone was determined both by radioimmunoassay (RIA) and by enzymeimmunoassay (EIA). Values obtained by EIA were considerably lower than values obtained by RIA. This may be partly due to the fact that only RIA values were corrected for procedural losses. Blood samples were taken on day 1 (= day of insemination) and on days 24, 27 and 30 after insemination (p.i.). Additional samples from pregnant animals were taken around day 170 p.i.. Normal progesterone values during oestrus were lower than 0.5 ng/ml, and generally the same low values were found in case of non-pregnancy at days 24, 27 and 30 p.i.. Pregnant animals showed in all cases progesterone concentrations higher than 0.5 ng/ml at days 24, 27 and 30, as well as around day 170 p.i.. These preliminary results indicate that the analysis of progesterone in plasma may be suitable for fertility control in the swamp buffalo. Furthermore we suggest that a modified EIA method can be used as a simple and rapid oestrus detection test under field conditions. 相似文献
89.
An ammonia-oxidizing, autotroph growing, slender, curved rod was isolated from the soil of Hawaii. It is well distinguishable from any other nitrifying bacteria thus far described by their morphology. The cells are 1.1–3.0 m long and 0.3–0.4 m wide. They are motile by means of 1–4 subpolar to lateral flagella. In contrast to most of the ammonia-oxidizing bacteria the isolated vibrio is void of an extensive cytomembrane system. To categorize this not yet described species we propose to create the new genus Nitrosovibrio and to classify the isolated strain as Nitrosovibrio tenuis. 相似文献
90.
Denitrification is an important process in the nitrogen (N) balance of intensively managed grassland, especially on poorly drained peat soils. Aim of this study was to quantify the N loss through denitrification in the top and sub soil of grassland on peat soils. Sampling took place at 2 sites with both control (0 N) and N fertilised (+ N) treatments. Main difference between the sites was the ground water level. Denitrification was measured on a weekly basis for 2 years with a soil core incubation technique using acetylene (C2H2) inhibition. Soil cores were taken from the top soil (0–20 cm depth) and the sub soil (20–40 cm depth) and incubated in containers for 24 hours. The denitrification rate was calculated from the nitrous oxide production between 4 and 24 hours of incubation. Denitrification capacities of the soils and the soil layers were also determined.The top soil was the major layer for denitrification with losses ranging from 9 to 26 kg N ha–1 yr–1 from the O N treatment. Losses from the top soil of the + N treatment ranged from 13 to 49 kg N ha–1 yr–1. The sub soil contributed, on average, 20% of the total denitrification losses from the 0–40 layer. Losses from the 0–40 cm layer were 2 times higher on the + N treatment than on the O N treatment and totalled up to 70 kg N ha–1 yr–1. Significant correlation coefficients were found between denitrification activity on the one hand, and ground water level, water filled pore space and nitrate content on the other, in the top soil but not in the sub soil. The denitrification capacity experiment showed that the availability of easily decomposable organic carbon was an important limiting factor for the denitrification activity in the sub soil of these peat soils. 相似文献