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Epp T Waldner C 《The Canadian veterinary journal. La revue veterinaire canadienne》2012,53(2):144-150
This study describes biological hazards reported by veterinarians working in western Canada obtained through a self-administered mailed questionnaire. The potential occupational hazards included as biological hazards were zoonotic disease events, exposure to rabies, injuries due to bites and scratches, and allergies. Only 16.7% (136/812) of responding veterinarians reported the occurrence of a zoonosis or exposure to rabies in the past 5 years; the most commonly reported event was ringworm. Most bites and scratches (86%) described by 586 veterinarians involved encounters with cats; 81% of the resulting 163 infections were due to cat bites or scratches. Approximately 38% of participants reported developing an allergy during their career, with 41% of the affected individuals altering the way they practiced in response to their allergy. 相似文献
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Zooplankton grazers consume appreciable amounts of algae that are not digested. Indigestibility has been considered of adaptive value to the algae and an unqualified disadvantage to the grazer. In Cartesian diver experiments, freshly killed copepods (Acanthocyclops vernalis) produced significant amounts of oxygen when exposed to the light, even after 24 hours of starvation. Also, significant amounts of oxygen were consumed by dead copepods in the dark. These observations suggest that the copepod gut is well suited for photosynthesis by ingested algae. 相似文献
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Fifty years of herbicide research: comparing the discovery of trifluralin and halauxifen‐methyl 
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下载免费PDF全文 Fifty years separate the commercialization of the herbicides trifluralin and halauxifen‐methyl. Despite the vast degree of technological change that occurred over that time frame, some aspects of their discovery stories are remarkably similar. For example, both herbicides were prepared very early in the iterative discovery process and both were developed from known lead compound structures by hypothesis‐driven research efforts without the use of in vitro assays or computer‐aided molecular design. However, there are aspects of the halauxifen‐methyl and trifluralin discovery stories that are substantially different. For example, the chemical technology required for the cost‐effective production of halauxifen‐methyl simply did not exist just two decades prior to its commercial launch. By contrast, the chemical technology required for the cost‐effective production of trifluralin was reported in the chemical literature more than two decades prior to its commercial launch. In addition, changes in regulatory environment since the early 1960s ensured that their respective discovery to commercial launch stories would also differ in substantial ways. Ultimately, the time and cost required to develop and register halauxifen‐methyl demanded a global initial business case while the lower registration hurdles that trifluralin cleared enabled a narrow initial business case mainly focused on the USA. © 2017 Society of Chemical Industry 相似文献
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Lee KH Dinner AR Tu C Campi G Raychaudhuri S Varma R Sims TN Burack WR Wu H Wang J Kanagawa O Markiewicz M Allen PM Dustin ML Chakraborty AK Shaw AS 《Science (New York, N.Y.)》2003,302(5648):1218-1222
The immunological synapse is a specialized cell-cell junction between T cell and antigen-presenting cell surfaces. It is characterized by a central cluster of antigen receptors, a ring of integrin family adhesion molecules, and temporal stability over hours. The role of this specific organization in signaling for T cell activation has been controversial. We use in vitro and in silico experiments to determine that the immunological synapse acts as a type of adaptive controller that both boosts T cell receptor triggering and attenuates strong signals. 相似文献
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