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The Fungal Genetics Stock Center (FGSC) was established in 1960 to ensure that important strains used in early genetics research were available to subsequent generations of fungal geneticists. Originally, only mutant strains were held. At present, any organism that has had its genome sequenced is a genetic system and so the FGSC has added many new organisms. The FGSC is well integrated in its core community and, as research came to depend on cloned genes, vectors and gene libraries, the FGSC included these materials. When the community expanded to include plant and human pathogens, the FGSC adopted these systems as well. Wild isolates from around the world have also proven instrumental in answering important questions. The FGSC holds tremendous diversity of the Neurospora species, which form the core of the collection. The growth in the number of strains distributed illustrates the growth in research on fungi. Because of its position near the centre of the fungal genetics effort, the FGSC is also the first to see trends in research directions. One recent example is the 300% jump in requests for strains of Neurospora crassa carrying a mutation that makes them sensitive to high salt concentration. These strains were seldom requested over many years, but became among our most popular resources following the demonstration of their utility in studying fungicide resistance. This exemplifies why materials need to be preserved without regard to their immediate perceived value and reinforces the need for long-term support for preservation of a broad variety of genetic resources.  相似文献   
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 The proteasome is a large multicatalytic proteinase that plays a role in the generation of peptides for presentation by major histocompatibility complex class I molecules. The 20S proteolytic core of mammalian proteasomes is assembled from a group of 17 protein subunits that generate a distinctive pattern of spots upon two-dimensional gel electrophoresis. The genes for most of these subunits have been cloned from humans and rats. We isolated cDNA clones for the mouse orthologues of ten of the subunits [PSMA1 (C2), PSMA2 (C3), PSMA3 (C8), PSMA4 (C9), PSMA5 (ZETA), PSMA6 (IOTA), PSMA7 (C6-I), PSMB2 (C7-I), PSMB3 (C10-II), and PSMB5 (X)] to complete the cloning of all of the mouse subunits. Using antisera raised against these subunits or their orthologues, we verified the identity of these proteins by two-dimensional NEPHGE-PAGE. Received: 8 March 1999 / Accepted: 8 April 1999  相似文献   
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Abstract

Antiquated petroleum refining methods may exacerbate polycyclic aromatic hydrocarbons (PAHs) in ambient air. There is currently an aging, yet active refinery on the island of Curaçao that has been the subject of public health concern. The objective of this study was to determine if ambient PAHs surrounding this refinery exceeded public health guidelines and investigate potential public health risks by calculating risk probability estimates. A number of recommended guidelines for the protection of public health from ambient PAHs were exceeded in Curaçao. Cumulative lifetime risk estimates for carcinogenic effects exceeded the upper bound level of acceptable risk at sites located both upwind and downwind of the petrochemical complex in 2011 and decreased to within the range considered acceptable in 2014. Risk probability estimates were highest for children and either exceeded or were approaching the upper bound advisory levels in 2011. Results indicate inhalation risks are higher at sites located downwind from the petrochemical complex compared to those upwind. This emphasizes the potential for higher risk probability estimates for residents that may have higher susceptibility, warranting the need for further health assessments in these populations and underscores the importance for continued monitoring of PAH sources and levels in Curaçao.  相似文献   
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Journal of Mathematical Biology - Many disease transmission models exhibit a threshold behaviour based on the basic reproduction number $${\mathcal {R}}_0$$ , where the disease-free equilibrium is...  相似文献   
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