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This is a review of current post-harvest entomology research conducted by the Agricultural Research Service, the research branch of the US Department of Agriculture. The review covers both durable and perishable commodities. Research on biochemistry, genetics, physiology, monitoring and control of insects infesting stored grain, dried fruits and nuts, and processed commodities is reviewed. Research on development of quarantine treatments, particularly for fruit flies, is also reviewed, including research on thermal and irradiation treatments and a discussion of risk management for quarantine pests. Two areas of research are covered more extensively: a project to map the genome of the red flour beetle, Tribolium castaneum, and the use of near-infrared spectroscopy for detection of hidden infestations in grain, quantification of insect fragments in food, determination of quality in dried fruits, identification of insect species and age-grading insects. Future research directions are identified.  相似文献   
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OBJECTIVE: To describe a technique for endoscope-assisted disruption and removal of urinary calculi using a holmium:YAG laser in sedated, standing horses. STUDY DESIGN: Retrospective study. ANIMALS: Six horses with urinary calculi. METHODS: A holmium:YAG laser was used to disrupt naturally occurring urinary calculi in horses (4 geldings, 1 stallion, 1 mare). Ischial urethrotomy was performed in male horses to provide a portal for the endoscope and laser fiber. Calculus fragments were removed by a combination of lavage, transendoscopic basket snare removal, forceps, and digital manipulation. Ischial urethrotomies healed by second intention. Follow-up was obtained by recheck examination and telephone interview of owners. RESULTS: No major operative or postoperative complications occurred. Two calculi (1 stallion and 1 mare) were fragmented by a combination of laser ablation and manual disruption with a lithotrite. Postoperative dysuria occurred in the mare, but resolved after 1 month. Mean (+/- SD) follow-up was 306 +/- 149 days; no other complications were reported. CONCLUSIONS: Calcium carbonate urinary calculi (up to 15 cm in diameter) in horses can be effectively fragmented with a holmium:YAG laser. It is not known if this technique would be completely effective for larger calculi or extremely dense calculi. CLINICAL RELEVANCE: Calculus disruption by an endoscopically assisted holmium:YAG laser offers a minimally invasive method that can be performed in standing horses and that minimizes patient risk.  相似文献   
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The authors have previously reported the development of a novel technique for sampling and preparing tissue slides for routine microscopic examination, without the use of a microtome. Termed "RAMP" (Rapid Adhesive Mediated Procedure), this simple, albeit somewhat crude, technique holds promise as a method that can be used in the field by veterinary practitioners for rapid microscopic evaluations to obtain early preliminary estimates of the nature of a mass or lesion. We incorporated the use of this method into a gross anatomy course in an attempt to gauge its utility for novices in tissue sampling and histology slide preparation. By having each group of students take a tissue sample from their cadaver, the activity simulated an actual necropsy situation in which practitioners in the field might use the technique. Because students were able to follow their specimen from sampling to microscopic examination, the activity provided a valuable integration of their learning of gross and microscopic anatomy. We conducted an evaluation of the process and the resulting slides with two successive classes of students. We conclude that the RAMP method is reasonably successful in the hands of individuals not trained in tissue preparation; was well received by the students as a valuable learning tool; and could potentially yield useful histological information for practicing veterinarians. Limitations of the method are also discussed.  相似文献   
45.
ABSTRACT The development and genetic characterization of four near-isogenic lines (NILs) of cotton (Gossypium hirsutum) is described herein. Each line contains a single, but different, gene for resistance to bacterial blight caused by Xanthomonas campestris pv. malvacearum. The lines were derived using at least six backcrosses to the susceptible recurrent parent 'Acala 44', followed by single plant-progeny row selection for uniformity. The NILs are homozygous for the B(2), B(4), B(In), or b(7) genes and are designated as AcB(2), AcB(4), AcB(In), and Acb(7), respectively. In the 'Acala 44' background, B(2), B(4), and B(In) are partially dominant genes; b(7) is partially recessive. Relative strengths of resistance conferred by those genes toward race 1 of the pathogen were B(4) b(7)>B(In) B(2). B(4), B(In), and b(7) each conferred resistance toward X. campestris pv. malvacearum carrying a single avirulence gene, whereas B(2) was less specific.  相似文献   
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OBJECTIVE : To determine the feasibility of indirect suture passage around the right portal vein for attenuation of right-sided intrahepatic portosystemic shunts (IHPSS). STUDY DESIGN : Anatomic study of cadavers and prospective evaluation of clinical cases. ANIMALS : Nine canine cadavers (median weight, 20.5 kg) and 6 client-owned dogs suspected of having right-sided IHPSS. METHODS : Silicone casts of the caudal vena cava and pre- and intrahepatic portal veins were made in fresh canine cadavers. A suture was passed dorsal to the portal vein above and below its bifurcation and pulled laterally so that it surrounded the right portal vein. The number and size of portal and caudal vena cava branches that interfered with the suture passage were recorded. Intra- and postoperative complications were evaluated in 3 dogs with right-sided IHPSS and 3 dogs suspected of having right-sided IHPSS that had right portal vein dissection and occlusion using this technique. RESULTS : Suture passage and placement around the right portal vein were easily accomplished in all 9 specimens. A 1 mm branch from the dorsal surface of the right portal vein was included in the encircling ligature in 4 specimens. The dissection technique was used successfully in 3 dogs with right-sided IHPSS and 2 other clinical cases. The portal branch to the papillary process of the caudate lobe interfered with suture placement in 1 dog with a central IHPSS. CONCLUSIONS : Indirect suture passage for ligation of the right portal vein can be successfully performed in normal dogs and dogs with congenital portosystemic shunts. CLINICAL RELEVANCE : Hemorrhage, vascular trauma, and surgery time may be reduced using this technique for attenuation of right-sided IHPSS.  相似文献   
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Advances in understanding the effects of early education have benefited public policy and developmental science. Although preschool has demonstrated positive effects on life-course outcomes, limitations in knowledge on program scale, subgroup differences, and dosage levels have hindered understanding. We report the effects of the Child-Parent Center Education Program on indicators of well-being up to 25 years later for more than 1400 participants. This established, publicly funded intervention begins in preschool and provides up to 6 years of service in inner-city Chicago schools. Relative to the comparison group receiving the usual services, program participation was independently linked to higher educational attainment, income, socioeconomic status (SES), and health insurance coverage, as well as lower rates of justice-system involvement and substance abuse. Evidence of enduring effects was strongest for preschool, especially for males and children of high school dropouts. The positive influence of four or more years of service was limited primarily to education and SES. Dosage within program components was mostly unrelated to outcomes. Findings demonstrate support for the enduring effects of sustained school-based early education to the end of the third decade of life.  相似文献   
50.
Role of genotype in the cycle of violence in maltreated children   总被引:1,自引:0,他引:1  
We studied a large sample of male children from birth to adulthood to determine why some children who are maltreated grow up to develop antisocial behavior, whereas others do not. A functional polymorphism in the gene encoding the neurotransmitter-metabolizing enzyme monoamine oxidase A (MAOA) was found to moderate the effect of maltreatment. Maltreated children with a genotype conferring high levels of MAOA expression were less likely to develop antisocial problems. These findings may partly explain why not all victims of maltreatment grow up to victimize others, and they provide epidemiological evidence that genotypes can moderate children's sensitivity to environmental insults.  相似文献   
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