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551.
552.
David G. Ainley Peter R. Wilson Kerry J. Barton Grant Ballard Nadav Nur Brian Karl 《Polar Biology》1998,20(5):311-319
We investigated the diet and aspects of foraging effort among Adélie penguins (Pygoscelis adeliae) breeding at three colonies on Ross Island, in the southwestern Ross Sea – Capes Royds, Bird and Crozier – during the chick-provisioning
period of three austral summers, 1994–1995, 1995–1996 and 1996–1997. During the study period, pack-ice cover differed in waters
offshore of these colonies, by colony, seasons and year. Diet differed among colonies only slightly. The fish Pleuragramma antarcticum was the most important prey, especially during years or periods within years when little pack ice was present. With respect
to krill, which composed the remainder of diet, juvenile Euphausia crystallorophias were consumed predominantly in a year of heavy pack-ice cover; more adult krill were consumed in 2 years when pack ice was
sparse. Foraging trip duration differed by colony, season and year and was related directly to distance from the colony to
the nearest pack ice. The amount of food brought to chicks increased as trip duration increased, to a point (2 days), but
then decreased as duration increased further (up to 4 days). On the basis of data on mass of parents and of meal sizes to
chicks, it appeared that on the longest trips more of the food gathered by parents was used for self maintenance; on the longest
trips, parents lost body mass. Successful foraging during chick rearing, the period when adult foraging is most intense, appears
to depend on the proximity of pack ice to nesting colonies for this penguin species.
Received: 1 October 1997 / Accepted: 25 April 1998 相似文献
553.
Uzi Nur 《Journal of morphology》1972,137(2):243-256
Males of the European elm scale, Gossyparia spuria (Erioccoccidae) have two Malphigian tubules, each made up of mononucleate and binucleate cells. Both types of cells may contain heterochromatic (H) chromosomes which form an H body. The cells with H bodies (H cells) usually appeared singly anywhere along the tubule. However, when two or more H cells were present they tended to be closer to each other than would be expected by chance. The possible origin of this tendency is discussed. Following squashing, the nuclei of the binucleate cells were much larger than those of most other somatic cells, suggesting that they were highly endopolyploid. However, the H bodies of the cells of the tubules were of about the same size as those of the other cells. These observations suggested that the H chromosomes of the binucleate cells did not replicate while the euchromatic chromosomes of these cells replicated several times. The great majority of the nuclei of the H cells contained a single H body per nucleus. An analysis of the number of H bodies in binucleate cells indicated that when two H bodies were present in the same nucleus they usually did not fuse. Thus, they were believed also not to fuse in the mononucleate cells. Since almost all the mononucleate H cells had only a single H body (rather than 2) it was concluded that they did not originate from binucleate cells by nuclear fusion. 相似文献
554.
Meat-eating was observed for the first time among a population of wild orang utans at Gunung Leuser National Park, Sumatra.
An adult female who was consorting with an adult male consumed a gibbon (Hylobates lar) carcass. There was no food sharing between the consort pair. The absence of food sharing is interpreted as indicative of
the anti-social attitude of adult orang utans. 相似文献
555.
Abdi Wira Septama Monika Arvia Chiara Gabriel Turnip Aprilia Nur Tasfiyati Rizna Triana Dewi Erlia Anggrainy Sianipar Amit Jaisi 《化学与生物多样性》2023,20(6):e202201205
Pseudomonas aeruginosa can regulate its pathogenicity via quorum sensing (QS) system. Zingiber cassumunar and Z. officinale have been used for the treatment of infectious diseases. The study aimed to evaluate and compare the chemical constituents, antibacterial, and QS inhibitor of Z. cassumunar essential oils (ZCEO) and Z. officinale essential oils (ZOEO). The chemical constituent was analysed using GC/MS. Broth microdilution and spectrophotometry analysis were used to evaluate their antibacterial and QS inhibitor activities. The main constituent of ZOEO with percent composition above 6 % (α-curcumene, α-zingiberene, β-sesquiphellandrene, and β-bisabolene, α-citral, and α-farnesene) were exist in a very minimal percentage less than 0.7 % in Z. cassumunar. All major components of ZCEO with percentages higher than 5 % (terpinen-4-ol, sabinene, γ-terpinene) were present in low proportion (<1.18 %) in Z. officinale. ZCEO demonstrated moderate antibacterial activity against P. aeruginosa. The combination of ZCEO and tetracycline showed a synergistic effect (FICI of 0.5). ZCEO exhibited strong activity in inhibiting biofilm formation. ZCEO at MIC (62.5 μg/mL) was able to reduce pyoverdine, pyocyanin, and proteolytic activity. This is the first report on the activity of ZCEO in the inhibition of P. aeruginosa QS system and it may be used to control the pathogenicity of P. aeruginosa. 相似文献
556.
M L Bruss C E Cornelius J A Himes 《Comparative biochemistry and physiology. A, Comparative physiology》1983,76(2):339-344
Intravenous infusion of bilirubin (BR) at 171 micrograms/min/kg into rabbits resulted in biliary concentration of BR increasing from 3.8 (control) to 243 mg/dl and BR excretion increasing from 1.7 to 66 micrograms/min/kg. BR infusion resulted in biliary concentrations of biliverdin (BV) increasing from 9.1 to 30 g/dl and BV excretion increasing from 4.2 to 8.2 micrograms/min/kg. BR infusion produced a progressive decline in bile flow. BV was the predominant bile pigment in control rabbits fed either an alfalfa-based or chlorophyll-free diet. These results imply that rabbits can oxidize BR to BV. 相似文献
557.
558.
Reversal of Heterochromatization and the Activity of the Paternal Chromosome Set in the Male Mealy Bug 总被引:5,自引:2,他引:3 下载免费PDF全文
Uzi Nur 《Genetics》1967,56(3):375-389
559.
To establish a definite diagnosis for pulmonary hydatid disease, combination of radiology and serology is useful. In this study, 19 preoperative sera from patients with surgically confirmed pulmonary hydatidosis, 40 sera from patients with other parasitosis and pulmonary diseases, and 20 sera from healthy donors were evaluated using 4 different serological tests, i.e., the commercial ELISA (ELISA-kit) test, the ELISA (ELISA-lab) test prepared in our laboratory, the commercial indirect hemagglutination assay kit (IHA-kit) test, and the IHA test using sensitized sheep red blood cells with tannic acid (IHA-TA). The ELISA-kit was the most sensitive (84.2%) and the most specific test (100.0%). The ELISA-kit also demonstrated the highest positive (100.0%) and negative (95.2%) predictive values. The sensitivity of the ELISA-lab test, that we prepared, was found to be 73.6%, whereas the IHA-kit test and the IHA-TA test were found to be 73.6% and 68.4%, respectively. The specificity of these tests was 96.6%, 98.3%, and 83.3%, respectively. When all 4 tests were assessed together, it was found that the sensitivity had risen to 94.7%. When the ELISA-kit was assessed with the IHA-kit and IHA-TA together, it was found that the sensitivity was 89.5% and 84.2%, respectively. Likewise, the combination of the ELISA-lab and IHA-kit or IHA-TA allowed us to achieve a sensitivity of 84.2% in cases of pulmonary echinococcosis. In conclusion, the diagnosis would be imminent if least 2 tests were applied together. 相似文献