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排序方式: 共有161条查询结果,搜索用时 9 毫秒
1.
The genes coding for human pro alpha 1(IV) collagen and pro alpha 2(IV) collagen are both located at the end of the long arm of chromosome 13. 总被引:5,自引:4,他引:1 下载免费PDF全文
C D Boyd S E Toth-Fejel I K Gadi M Litt M R Condon M Kolbe I K Hagen M Kurkinen J W Mackenzie E Magenis 《American journal of human genetics》1988,42(2):309-314
We have isolated and characterized a cDNA clone containing DNA sequences coding for the noncollagenous carboxy-terminal domain of human pro alpha 2(IV) collagen. Using this cDNA clone in both Southern blot analysis of DNA isolated from human-mouse somatic-cell hybrids and in situ hybridization of normal human metaphase chromosomes, we have demonstrated that the gene coding for human pro alpha 2(IV) collagen is located at 13q33----34, in the same position on chromosome 13 as the pro alpha 1(IV) collagen gene. 相似文献
2.
Gadi Katzir Arnon Lotem Nathan Intrator 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1989,165(4):573-576
Summary This paper attempts to verify the importance of spatial positioning of the eyes of reef heronsEgretta gularis schistacea, when coping with light refraction at the air-water interface. The herons' striking of prey, while their approach angle was restricted, was observed. (a) The herons' capture success in the restricted situation was markedly lower than in the unrestricted situation. (b) The points of strike (STR) in unsuccessful strikes differed from those of successful strikes, and from those of the unrestricted situation. (c) The larger the difference between the observed and the predicted ratio of prey depth to apparent prey depth, the higher the probability of missing a prey. These results support predictions of a model presented elsewhere (Katzir and Intrator 1987) that a heron will attempt to reach spatial positions at which prey's real depth and apparent depth are linearly correlated. 相似文献
3.
Gadi Katzir 《Animal behaviour》1981,29(3):835-841
Field experiments were conducted to demonstrate species recognition in Dascyllus aruanus. Aggression was used as a criterion for recognition. Free-living fish were presented with live stimuli in a choice situation where visual cues could be isolated from other cues. The stimuli were conspecific and heterospecific fish. Practically all the responses were aggressive. Aggression towards D. aruanus and Dascyllus marginatus was similar in its intensity, and higher than towards Dascyllus trimaculatus. Aggression towards Amphiprion bicinctus was negligible. Elimination of all but visual cues resulted in a decline in attack rate without changing attack preference. The high level of interspecific aggression limits the use of aggression as an indicator of species recognition under the presented experimental situation. 相似文献
4.
Zaid A. Abassi Marina Okun-Gurevich Niroz Abu Salah Hoda Awad Yossi Mandel Gadi Campino Ahmad Mahajna Giora Z. Feuerstein Mike Fitzpatrick Aaron Hoffman Joseph Winaver 《PloS one》2013,8(11)
Uncontrolled hemorrhage, resulting from traumatic injuries, continues to be the leading cause of death in civilian and military environments. Hemorrhagic deaths usually occur within the first 6 hours of admission to hospital; therefore, early prehospital identification of patients who are at risk for developing shock may improve survival. The aims of the current study were: 1. To establish and characterize a unique model of uncontrolled internal hemorrhage induced by massive renal injury (MRI), of different degrees (20-35% unilateral nephrectomy) in rats, 2. To identify early biomarkers those best predict the outcome of severe internal hemorrhage. For this purpose, male Sprague Dawley rats were anesthetized and cannulas were inserted into the trachea and carotid artery. After abdominal laparotomy, the lower pole of the kidney was excised. During 120 minutes, hematocrit, pO2, pCO2, base excess, potassium, lactate and glucose were measured from blood samples, and mean arterial pressure (MAP) was measured through arterial tracing. After 120 minutes, blood loss was determined. Statistical prediction models of mortality and amount of blood loss were performed. In this model, the lowest blood loss and mortality rate were observed in the group with 20% nephrectomy. Escalation of the extent of nephrectomy to 25% and 30% significantly increased blood loss and mortality rate. Two phases of hemodynamic and biochemical response to MRI were noticed: the primary phase, occurring during the first 15 minutes after injury, and the secondary phase, beginning 30 minutes after the induction of bleeding. A Significant correlation between early blood loss and mean arterial pressure (MAP) decrements and survival were noted. Our data also indicate that prediction of outcome was attainable in the very early stages of blood loss, over the first 15 minutes after the injury, and that blood loss and MAP were the strongest predictors of mortality. 相似文献
5.
The wheat midge, Sitodiplosis mosellana, is a serious pest of wheat worldwide. In North America, management of S. mosellana in spring wheat relies on the timely application of pesticides, based on midge adults levels caught in pheromone traps or seen via field scouting during wheat heading. In this context, biopesticides can be an effective alternative to pesticides for controlling S. mosellana within an Integrated Pest Management program. A field study using insect pathogenic fungus Beauveria bassiana GHA, nematode Steinernema Jeltiae with Barricade polymer gel 1%, pyrethrin, combined formulations of B. bassiana GHA and pyrethrin, Jasmonic acid (JA) and chlorpyrifos (chemical check) was performed to determine to which extent they affect midge larval populations, kernel damage levels, grain yield, and quality, and the impacts on adult parasitoid Macroglenes penetrans populations. The results indicated that biopesticides JA and S. Jeltiae were the most effective in reducing larval populations and kernel damage levels, and produced a higher spring wheat yield when compared to the water control at both study locations (East Valier and North Valier, Montana, USA). Increased test weight in wheat had been recorded with two previous biopesticides at East Valier but not for North Valier, when compared over water control. These results were comparable in efficacy to the chlorpyrifos. This study also suggested that B. bassiana and pyrethrin may work synergistically, as exemplified by lower total larval populations and kernel damage levels when applied together. This study did not demonstrate the effect of any treatments on M. penetrans populations. 相似文献
6.
7.
Yiying Zeng Gadi V. P. Reddy Zhihong Li Yujia Qin Yannan Wang Xubin Pan Fan Jiang Feng Gao Zi‐Hua Zhao 《Journal of Applied Entomology》2019,143(3):165-176
Since the start of the 20th century, many invasive alien species (IAS) have spread rapidly around the world, causing serious threats to economies, societies and the environment. Bactrocera dorsalis (Hendel) (Diptera: Tephritidae) is an important quarantine insect species in many countries that spread around the world over the last century. This review collected information on the distribution of B. dorsalis to explore the patterns of its invasion expansion. We found B. dorsalis to be distributed in 75 countries (comprised of 124 geographical distribution regions: provinces or states) in Asia, Africa, North America, South America and Oceania up to 2017. Asia and Africa were the most represented regions, accounting for 86.3% of the total number of countries. From 1910 to 1990, B. dorsalis was only found in five countries, but in the last three decades, it has experienced a sharp increase in its rate of spread, invading 70 more countries. Global temperature anomaly has significantly positive correlation with the spread of B. dorsalis. The results of this review provide a theoretical basis for understanding and predicting the continued spread of B. dorsalis under global changes. 相似文献
8.
Anamika Sharma Ramandeep K. Sandhi Shabeg S. Briar John H. Miller Gadi V. P. Reddy 《Journal of Applied Entomology》2019,143(4):460-469
Wireworms, the larvae of click beetles (Elateridae), are difficult to manage due to their habitats and behaviour. Wireworms pose a major threat to the wheat crop in the north‐western USA. Seed treatment with neonicotinoids, biological control management and some cultural controls are recommended to manage these pests. Trap cropping is an emerging way to manage wireworms. In strawberry and potato crops, trap cropping has been found effective at attracting wireworms away from the principal crop. An earlier study in the Golden Triangle area of Montana found that pea and lentil could be effective trap crops for managing wireworms in spring wheat. In the present study, experiments were conducted at two locations. The effectiveness of peas and lentils as trap crops with wheat at different seeding densities was assessed [pea at 0, 4, 8, 16 seeds/sq.ft. or 0, 43, 86, 172 seeds/sq.m.; lentil at 0, 6, 12, 18 OR 0, 65, 130, 194 seeds/sq.m.; both with wheat at 0, 11, 22, or 28 seeds/sq.ft. or 0, 120, 230, 300 seeds/sq.m.] in a randomized design where all three crops were intercropped. Both trap crops were found to be effective in protecting wheat at standard seeding rates of 8 seeds/sq.ft. for pea and 12 seeds/sq.ft. for lentils. At these seeding rates, higher numbers of wireworms were found to be attracted to the trap crop, resulting in higher yield (7%–10%) of the associated spring wheat plant stands at 22 seeds/sq.ft. To develop an effective trap crop strategy, the pea–wheat and lentil–wheat spatial patterns that are possible need to be assessed in further field trials. Proper design and evaluation of the cost–benefit ratio of pea and lentil as trap crops are likely to produce good results for wheat crops in Montana. 相似文献
9.
Ehsan Ghaemmaghami Yaghoub Fathipour Abdoolnabi Bagheri Ali Asghar Talebi Gadi V.P.Reddy 《Insect Science》2021,(1):180-190
Trichogramma brassicae(Bezdenko)is an important biological control agent that has been used widely against many lepidopteran pests.Commonly,colonies of Tri-chog... 相似文献
10.
Rott Ruth Liveanu Varda Drager Robert G. Higgs Dave Stern David B. Schuster Gadi 《Plant molecular biology》1999,40(4):679-686
The 3 ends of chloroplast mRNAs are produced by the processing of longer precursors. The 3 ends of most plastid mRNAs are located at, or several nucleotides downstream of, stem-loop structures, which act as 3-end-processing signals and RNA stability elements. In chloroplasts of the green alga Chlamydomonas reinhardtii, 3-end maturation of atpB mRNA involves endonucleolytic cleavage of the pre-mRNA at an AU-rich site located about 10 nucleotides downstream of the stem-loop structure. This cleavage is followed by exonucleolytic resection to generate the mature 3 end. In order to define critical nucleotides of the endonucleolytic cleavage site, we mutated its sequence. Incubation of synthetic atpB pre-RNAs containing these mutations in a chloroplast protein extract resulted in the accumulation of 3-end-processed products. However, in two cases where the AU-rich sequence of this site was replaced with a GC-rich one, the 3 end of the stable processing product differed from that of the wild-type product. To examine whether these mutations affected atpB mRNA processing or accumulation in vivo, the endogenous 3 UTR was replaced with mutated sequences by biolistic transformation of Chlamydomonas chloroplasts. Analysis of the resulting strains revealed that the accumulation of atpB mRNA was approximately equal to that of wild-type cells, and that a wild-type atpB 3 end was generated. These results imply that Chlamydomonas atpB 3 processing parallels the situation with other endonucleases such as Escherichia coli RNAse E, where specific sequences are required for correct in vitro processing, but in vivo these mutations can be overcome. 相似文献