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371.
The endostyle is a glandular and ciliated groove lining the pharyngeal floor of tunicates. This paper describes the histological
structure of this organ in two new species of doliolid-like animals, Doliopsis bahamensis and Paradoliopsis harbisoni, and compares it with that of Doliolum nationalis. The results confirm the distinction between the Doliolida and the other Thaliacea.
Received: 7 November 1996 / Accepted: 6 December 1996 相似文献
372.
Allele-specific amplification for preimplantation genetic diagnosis (PGD) of spinal muscular atrophy
Céline Moutou Nathalie Gardes Catherine Rongières Jeanine Ohl Karima Bettahar-Lebugle Christiane Wittemer Pierre Gerlinger Stéphane Viville 《黑龙江环境通报》2001,21(6):498-503
We have developed a new allele-specific amplification method for the preimplantation genetic diagnosis (PGD) of spinal muscular atrophy (SMA; Werdnig-Hoffmann disease) from a single cell. This method is based on the detection of the deletion of exon 7 of the telomeric copy of the survival motor neurone (SMNt) gene. An oligonucleotide was designed to be specific to the SMNt nucleotidic sequence with exonic mismatch G (for SMNt)→A (for SMNc) at its 3′ end. This test produces reliable PCR products in 95% of single lymphoblasts (85/88) tested as well as in 16/16 blastomeres from normal controls. Specificity analysis showed that we were able to detect homozygous deletion of the SMNt gene in 99% of single lymphoblasts (103/104) from a SMA patient. No contamination was detected in 68 blanks tested. Multiple cell and DNA dilution analysis revealed that the test is accurate and specific up to 100 pg DNA and should thus also be suitable for PGD at the blastocyst stage. This rapid procedure requires a single round of fluorescent PCR and no restriction digestion, while previously described single cell methods include nested PCR followed by restriction enzyme digestion. Two PGD cycles for SMA using this procedure were performed in our centre. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
373.
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375.
Camille Codaccioni Olivier Picone Véronique Lambert Paul Maurice Léo Pomar Norbert Winer Laurent Guibaud Rose-Anne Lavergne Anne-Hélène Saliou Dorothée Quinio Alexandra Benachi Catherine Noel Yves Ville Fabrice Cuillier Christelle Pomares Nicole Ferret Denis Filisetti Anne-Sophie Weingertner Valérie Vequeau-Goua Estelle Cateau Guillaume Benoist Martine Wallon Marc Dommergues Isabelle Villena Laurent Mandelbrot 《黑龙江环境通报》2020,40(13):1741-1752
376.
Romain Amiot Delphine Angst Serge Legendre Eric Buffetaut François Fourel Jan Adolfssen Aurore André Ana Voica Bojar Aurore Canoville Abel Barral Jean Goedert Stanislaw Halas Nao Kusuhashi Ekaterina Pestchevitskaya Kevin Rey Aurélien Royer Antônio Álamo Feitosa Saraiva Bérengère Savary-Sismondini Jean-Luc Siméon Alexandra Touzeau Zhonghe Zhou Christophe Lécuyer 《Die Naturwissenschaften》2017,104(5-6):47
Oxygen isotope compositions of bone phosphate (δ18Op) were measured in broiler chickens reared in 21 farms worldwide characterized by contrasted latitudes and local climates. These sedentary birds were raised during an approximately 3 to 4-month period, and local precipitation was the ultimate source of their drinking water. This sampling strategy allowed the relationship to be determined between the bone phosphate δ18Op values (from 9.8 to 22.5‰ V-SMOW) and the local rainfall δ18Ow values estimated from nearby IAEA/WMO stations (from ?16.0 to ?1.0‰ V-SMOW). Linear least square fitting of data provided the following isotopic fractionation equation: δ18Ow = 1.119 (±0.040) δ18Op ? 24.222 (±0.644); R 2 = 0.98. The δ18Op–δ18Ow couples of five extant mallard ducks, a common buzzard, a European herring gull, a common ostrich, and a greater rhea fall within the predicted range of the equation, indicating that the relationship established for extant chickens can also be applied to birds of various ecologies and body masses. Applied to published oxygen isotope compositions of Miocene and Pliocene penguins from Peru, this new equation computes estimates of local seawater similar to those previously calculated. Applied to the basal bird Confuciusornis from the Early Cretaceous of Northeastern China, our equation gives a slightly higher δ18Ow value compared to the previously estimated one, possibly as a result of lower body temperature. These data indicate that caution should be exercised when the relationship estimated for modern birds is applied to their basal counterparts that likely had a metabolism intermediate between that of their theropod dinosaur ancestors and that of advanced ornithurines. 相似文献
377.
Jaffrezic A Jardé E Pourcher AM Gourmelon M Caprais MP Heddadj D Cottinet P Bilal M Derrien M Marti R Mieszkin S 《Journal of environmental quality》2011,40(3):959-968
Fecal contamination of water resources is evaluated by the enumeration of the fecal coliforms and Enterococci. However, the enumeration of these indicators does not allow us to differentiate between the sources of fecal contamination. Therefore, it is important to use alternative indicators of fecal contamination to identify livestock contamination in surface waters. The concentration of fecal indicators (, enteroccoci, and F-specific bacteriophages), microbiological markers (Rum-2-bac, Pig-2-bac, and ), and chemical fingerprints (sterols and stanols and other chemical compounds analyzed by 3D-fluorescence excitation-matrix spectroscopy) were determined in runoff waters generated by an artificial rainfall simulator. Three replicate plot experiments were conducted with swine slurry and cattle manure at agronomic nitrogen application rates. Low amounts of bacterial indicators (1.9-4.7%) are released in runoff water from swine-slurry-amended soils, whereas greater amounts (1.1-28.3%) of these indicators are released in runoff water from cattle-manure-amended soils. Microbial and chemical markers from animal manure were transferred to runoff water, allowing discrimination between swine and cattle fecal contamination in the environment via runoff after manure spreading. Host-specific bacterial and chemical markers were quantified for the first time in runoff waters samples after the experimental spreading of swine slurry or cattle manure. 相似文献
378.
Sheng Fulai Gary Flomenhoft Timothy J. Downs MaÁngeles Grande‐Ortiz Dana Graef Bert Scholtens Arthur P.J. Mol David A. Sonnenfeld Gert Spaargaren Rajeev K. Goel Edward W.T. Hsieh Serban Scrieciu Reinhard Steurer Christine Polzin Genia Kostka Tiho Ancev Elke Pirgmaier Frank Boons Karl‐Henrik Robèrt Christopher Bryant Ke Zhou Surya Raj Acharya David Huberman Denis J. Sonwa Michelle Mycoo Dabo Guan Klaus Hubacek U. Rashid Sumaila Hector G. Lopez‐Ruiz G. Jason Jolley Michael L. Dougherty André Francisco Pilon Ravi Prakash Tulus Tambunan Sebastian Hermann 《Natural resources forum》2011,35(1):63-72
379.
Marielle GuéguenRégis Baron Michèle BardouilPhilippe Truquet Hansy HaberkornPatrick Lassus Laurent BarilléZouher Amzil 《Ecological modelling》2011,222(18):3394-3402
The aim of this study was to evaluate the importance of biotransformation of paralytic shellfish toxins during the detoxification process in contaminated oysters. Mathematical models based upon the detoxification patterns of digestive gland and other tissues were developed. It was demonstrated that biotransformations do not seem to play an important role in digestive gland or other tissue detoxification kinetics with our data set. Moreover, different toxin transfers from digestive gland toward other tissues were investigated. No significant transfer was highlighted in our data set. These first conclusions were drawn after comparing the results obtained from 13 biotransformations and identifiable transfer scenarios. Finally, to determine a more robust model, all 12 states corresponding to toxic compounds and tissues were aggregated into a single state model. The best adjustment was obtained with a simple one-compartment model based on total flesh toxicity with elimination rate expressed by a function depending on initial concentrations of GTX3 and GTX2 (i.e. the two major toxic compounds found in contaminated oysters). 相似文献
380.
Fernando Amor Patrocinio Ortega Michael J. Jowers Xim Cerdá Johan Billen Alain Lenoir Raphaël R. Boulay 《Behavioral ecology and sociobiology》2011,65(7):1473-1482
In many ants, young queens disperse by flying away from their natal nest and found new colonies alone (independent colony
founding, ICF). Alternatively, in some species, ICF was replaced by colony fission, in which young queens accompanied by workers
found a new colony at walking distance from the mother nest. We compared the queen morphology of Cataglyphis floricola, which disperses by fission, with that of its most likely living ancestor, Cataglyphis emmae, which disperses by ICF. As in other species, the transition from ICF to fission is associated with queen miniaturization.
Interestingly, C. floricola presents two types of small queens: brachypters (with short non-functional wings) and ergatoids (worker-like apterous queens).
Ergatoids are, on average, 2.8 mg lighter and have half the number of ovarioles than brachypters, which limits the advantage
for a colony to produce ergatoids instead of brachypters. Furthermore, more ergatoids are produced than brachypters, but their
individual survival rate is lower. During colony fission, 96% of the cocoons containing brachypters but only 31% of those
containing ergatoids are transferred to the daughter nests where, after emergence, they compete for becoming the next queen.
The remaining queen cocoons, which stay in the mother queen's nest, are eliminated by workers upon emergence, probably to
maintain monogyny. This waste of energy suggests that producing ergatoids instead of brachypters is unlikely to increase colony
efficiency. We argue that the evolution of ergatoids could derive from a selfish larval strategy, developing into worker-like
queens in spite of the colony interest. 相似文献