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671.
Bertone P Stolc V Royce TE Rozowsky JS Urban AE Zhu X Rinn JL Tongprasit W Samanta M Weissman S Gerstein M Snyder M 《Science (New York, N.Y.)》2004,306(5705):2242-2246
Elucidating the transcribed regions of the genome constitutes a fundamental aspect of human biology, yet this remains an outstanding problem. To comprehensively identify coding sequences, we constructed a series of high-density oligonucleotide tiling arrays representing sense and antisense strands of the entire nonrepetitive sequence of the human genome. Transcribed sequences were located across the genome via hybridization to complementary DNA samples, reverse-transcribed from polyadenylated RNA obtained from human liver tissue. In addition to identifying many known and predicted genes, we found 10,595 transcribed sequences not detected by other methods. A large fraction of these are located in intergenic regions distal from previously annotated genes and exhibit significant homology to other mammalian proteins. 相似文献
672.
The Atmosphere Structure Instrument on the Galileo probe detected wavelike temperature fluctuations superimposed on a 700-kelvin temperature increase in Jupiter's thermosphere. These fluctuations are consistent with gravity waves that are viscously damped in the thermosphere. Moreover, heating by these waves can explain the temperature increase measured by the probe. This heating mechanism should be applicable to the thermospheres of the other giant planets and may help solve the long-standing question of the source of their high thermospheric temperatures. 相似文献
673.
674.
Riehle MM Guelbeogo WM Gneme A Eiglmeier K Holm I Bischoff E Garnier T Snyder GM Li X Markianos K Sagnon N Vernick KD 《Science (New York, N.Y.)》2011,331(6017):596-598
Population subgroups of the African malaria vector Anopheles gambiae have not been comprehensively characterized owing to the lack of unbiased sampling methods. In the arid savanna zone of West Africa, where potential oviposition sites are scarce, widespread collection from larval pools in the peridomestic human habitat yielded a comprehensive genetic survey of local A. gambiae population subgroups, independent of adult resting behavior and ecological preference. A previously unknown subgroup of exophilic A. gambiae is sympatric with the known endophilic A. gambiae in this region. The exophilic subgroup is abundant, lacks differentiation into M and S molecular forms, and is highly susceptible to infection with wild Plasmodium falciparum. These findings might have implications for the epidemiology of malaria transmission and control. 相似文献
675.
The lead aerosol concentration at White Mountain, California, may be regarded as the present baseline concentration for atmospheric lead for the continental United States. The seasonal trend of lead aerosols at White Mountain and Laguna Mountain shows a summer maximum and a winter minimum. This is because both mountain sampling sites are well above the thermal (radiation) inversion, which normally occurs in the winter, trapping pollutants below the inversion boundary. 相似文献
676.
677.
基于表型信息和谱系信息估计基因加性效应值的种畜遗传评定方法在家畜遗传改良中发挥了很大作用,但因其无法真正了解控制经济性状的遗传本质,影响了家畜遗传改良的进一步进展。分子标记辅助选择可在一定程度上提高种畜遗传评定准确性,但在目前不能精确定位QTL或基因时,其效率受到很大影响。提高种畜遗传评定准确性的最有效途径应是直接利用控制经济性状的基因,后基因组时代的功能基因组研究的快速发展为实现这一目标提供了契机。同时,多个家畜品种基因组测序完成和大量SNP多态性的发现,使得利用覆盖全基因组多态性标记信息的基因组选择方法为家畜遗传评定开拓了又一条途径。 相似文献
678.
In Mediterranean climates, adoption and use of the ET-based scheduling method is limited to regions characterized by considerable contributions to evapotranspiration from fog interception, dew, and light rainfall. While the crop evapotranspiration is often accurately estimated, the water balance is frequently in error because a considerable portion of the energy expended is used to vaporize water from the plant surfaces rather from inside the leaves (i.e., transpiration). Growers in regions with considerable fog, dew, and light rainfall are hesitant to use ET-based scheduling because the cumulative crop evapotranspiration between irrigations is often considerably higher than the soil water depletion. A correction for these surface contributions is clearly needed to improve the water balance calculations and to enhance adoption of the ET-based scheduling method. In this paper, we present a simple, practical method to estimate the contribution of fog interception, dew, and light rainfall to daily crop evapotranspiration, and we show how to use the method to improve water balance calculations. 相似文献
679.
Field trials were carried out to assess the efficacy of a 4% azadirachtin (aza)-containing neem seed extract EC, against damage
by western flower thrips [Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae)] on nectarine crops in the Similkameen Valley, British Columbia, Canada. Several trials
were conducted during the years 1993 to 1995 to assess the repellent and larvicidal properties of aza, specifically: whether
it was effective against adult or larval thrips; how the effects differed with concentration of aza; and whether female WFT
avoided aza-treated flowers. Our results showed that aza has only limited effectiveness as a control agent against WFT on
nectarines and the current formulation does not appear to limit larval development sufficiently to be deemed a possible control
agent in this field situation. 相似文献
680.
E A Scott J R Heidel S P Snyder S Ramirez W A Whitler 《Journal of the American Veterinary Medical Association》1999,214(10):1527-1530
OBJECTIVE: To determine clinical and surgical abnormalities in, and long-term outcome of, horses that undergo surgery because of colic secondary to inflammatory bowel disease (IBD). DESIGN: Retrospective study. ANIMALS: 11 horses. PROCEDURE: Medical records of horses that had undergone abdominal surgery and in which IBD had been diagnosed on the basis of histologic examination of intestinal biopsy specimens were reviewed. RESULTS: 5 horses were examined because of acute colic and 6 were examined because of chronic colic. At surgery, all 11 horses had edematous or hemorrhagic bowel segments suggestive of IBD. In addition, 6 horses had circumferential mural bands (CMB) causing constriction of the small (4 horses) or large (2) intestine. Intestinal resections were performed in 7 horses. All 11 horses survived surgery and were discharged from the hospital; 10 horses were still alive at the time of follow-up (1.5 to 7 years after surgery). CLINICAL IMPLICATIONS: Results suggest that IBD is an uncommon cause of colic in horses. Surgical resection of segments of intestine with constrictive CMB may relieve clinical signs of colic. Horses with IBD that had surgery had a good prognosis for long-term survival. 相似文献