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排序方式: 共有837条查询结果,搜索用时 46 毫秒
831.
Aljomar Jos Vechiato Filho Karina Morais Faria Maria Cecília Querido de Oliveira Ariadne Padilha de Andrade Ana Carolina Prado-Ribeiro Alan Roger Santos-Silva Alvin G. Wee Thaís Bianca Brando 《Reports of Practical Oncology and Radiotherapy》2021,26(1):159
Radiotherapy is being performed in many situations as a curative approach for head and neck cancer instead of surgery due to the current novel coronavirus disease (COVID-19) pandemic. A recent publication reported that even hypofractionation was being conducted in order to reduce the daily exposure of both patients and the medical staff involved in cancer therapies. As a result, dental teams may be requested more frequently than usual to fabricate intraoral stents (IOS). Given that IOS may be a potential source of COVID-19 contagion, the main purpose of the present correspondence is to offer a guide on how health professionals may be safely presented in the room, on the management of the IOS and also how to sanitize the stents. 相似文献
832.
Carlo G. Casinovi Michele Framondino Giacomino Randazzo Francesco Siani 《Carbohydrate research》1974,36(1):67-73
Acetylation of methyl 6-O-trityl-α-D-glucopyranoside with one equivalent of acetic anhydride in pyridine yields, preferentially, the 4-acetate 8. The 2- and 3-acetates can be converted under mild alkaline conditions into 8, which is more stable towards acetyl migration. 相似文献
833.
Growth and respiration of juveniles of two pleuronectiforms ( Buglossidium luteum and Arnoglossus thori ) were studied. The first species has a single period of benthic recruitment (April), a growth pause in winter, and a very low winter metabolism (at 11°C). The second species has two peaks of recruitment (May–June and September–October), an exponential growth with no significant pause in winter, and little reduction of metabolism at 11°C.
Such differences are important factors allowing the sharing of the same biotope by these small benthic predators. 相似文献
Such differences are important factors allowing the sharing of the same biotope by these small benthic predators. 相似文献
834.
Cytokinesis is asymmetric along the apical–basal axis of epithelial cells, positioning the midbody near the apical domain. However, little is known about the mechanism and purpose of this asymmetry. We use live imaging of Drosophila follicle cell division to show that asymmetric cytokinesis does not result from intrinsic polarization of the main contractile ring components. We show that adherens junctions (AJs) maintain close contact with the apical side of the contractile ring during cytokinesis. Asymmetric distribution of AJ components within follicle cells and in the otherwise unpolarized S2 cells is sufficient to recruit the midbody, revealing that asymmetric cytokinesis is determined by apical AJs in the epithelia. We further show that ectopic midbody localization induces epithelial invaginations, shifting the position of the apical interface between daughter cells relative to the AB axis of the tissue. Thus, apical midbody localization is essential to maintain epithelial tissue architecture during proliferation. 相似文献
835.
836.
Luciano A Rigano María R Marano Atilio P Castagnaro Alexandre Morais Do Amaral Adrian A Vojnov 《BMC microbiology》2010,10(1):176
Background
Citrus Bacterial Canker (CBC) is a major, highly contagious disease of citrus plants present in many countries in Asia, Africa and America, but not in the Mediterranean area. There are three types of Citrus Bacterial Canker, named A, B, and C that have different genotypes and posses variation in host range within citrus species. The causative agent for type A CBC is Xanthomonas citri subsp. citri, while Xanthomonas fuscans subsp. aurantifolii, strain B causes type B CBC and Xanthomonas fuscans subsp. aurantifolii strain C causes CBC type C. The early and accurate identification of those bacteria is essential for the protection of the citrus industry. Detection methods based on bacterial isolation, antibodies or polymerase chain reaction (PCR) have been developed previously; however, these approaches may be time consuming, laborious and, in the case of PCR, it requires expensive laboratory equipment. Loop-mediated isothermal amplification (LAMP), which is a novel isothermal DNA amplification technique, is sensitive, specific, fast and requires no specialized laboratory equipment. 相似文献837.
Carlos A. Rosa Maria A. Resende Francisco A. R. Barbosa Paula B. Morais Sarah P. Franzot 《Hydrobiologia》1995,308(2):103-108
The yeast diversity in a paleo-karstic lake of the Lagoa Santa plateau was studied during March 1986–March 1987. Water samples
were collected monthly at five stations and the yeasts were isolated at 25 °C on Sabourad dextrose agar supplemented with
0.5% of yeast extract and 10 mg% of chloramphenicol. August and February showed the highest numbers of isolates, coinciding,
respectively with the beginning and the ending of stratification. Of 56 isolated species, Aureobasidium pullulans, Candida famata, Cryptococcus albidus, Cryptococcus laurentii, Rhodotorula glutinis, Rhodotorula rubra and Trichosporon cutaneum occurred at the highest frequencies. A. pullulans showed greatest prevalence during the dry period (winter), whereas C. famata, Cr. albidus, Cr. laurentii and Rh. rubra were prevalent during the rainy season (summer). Tr. cutaneum was distributed between July and November. Most isolates yeasts are associated with plants and soils, and are important in
decomposition of aquatic macrophytes. Furthermore, a possible role of these species as indicators of pollution is discussed. 相似文献