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Coastal Brook Trout (Salvelinus fontinalis) populations are found from northern Canada to New England. The extent of anadromy generally decreases with latitude, but the ecology and movements of more southern populations are poorly understood. We conducted a 33‐month acoustic telemetry study of Brook Trout in Red Brook, MA, and adjacent Buttermilk Bay (marine system) using 16 fixed acoustic receivers and surgically implanting acoustic transmitters in 84 individuals. Tagged Brook Trout used the stream, estuary (50% of individuals) and bay (10% of individuals). Movements into full sea water were brief when occurring. GAMM models revealed that transitions between habitat areas occurred most often in spring and fall. Environmental data suggest that use of the saline environment is limited by summer temperatures in the bay. Movements may also be related to moon phase. Compared to more northern coastal populations of Brook Trout, the Red Brook population appears to be less anadromous overall, yet the estuarine segment of the system may have considerable ecological importance as a food resource.  相似文献   
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Background: Platelet cryopreservation allows long-term storage and immediate availability of transfusion products.
Hypothesis: The addition of a preparation inhibiting platelet activation (Thrombosol, in 2% dimethyl sulfoxide [DMSO]) will enhance in vitro function and prolong in vivo survival of cryopreserved platelets compared with those preserved in 6% DMSO.
Animals: Thirty-three research dogs.
Methods: Prospective study. Eleven fresh canine apheresis platelet concentrates (PCs) were each split into 3 units: fresh and cryopreserved in 6% DMSO or Thrombosol. Platelet analysis, performed 1–10 weeks postfreezing, included in vitro functional testing and in vivo survival assessed by administration of biotinylated platelets.
Results: Platelet aggregation was diminished in cryopreserved PC. Cryopreserved platelets could be activated, as based on mean thrombin-stimulated P-selectin expression (6% DMSO, 23.0%; Thrombosol, 18.4%), although to a lesser extent than fresh PC (49.1%) ( P < .0001). The mean maximum in vivo platelet recovery for fresh PC was 80.3%, significantly greater than recovery for 6% DMSO (49.2%) and Thrombosol PC (43.7%) ( P ≤ .001). The half-life (days) of fresh PC (3.8 ± 0.4) was significantly ( P < .002) greater than that of 6% DMSO (1.9 ± 1.0) and Thrombosol (2.4 ± 1.1) PC, with no difference ( P = .3) between cryopreserved PC.
Conclusions and Clinical Importance: Cryopreservation of canine platelets using Thrombosol did not provide any advantage over preservation using 6% DMSO. Cryopreserved platelets can be activated in vitro and provide therapeutic benefit when fresh platelets are unavailable. Further studies are needed to assess their in vivo hemostatic function.  相似文献   
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Objectives: To report the clinical features of horses with fluid‐filled masses associated with the digital flexor tendon sheath (DFTS) and outcome after surgery. Study Design: Case series. Animals: Horses (n=10) Methods: Medical records of horses with fluid‐filled masses associated with the DFTS were reviewed and the clinical features, diagnostic methods, treatment, histopathology, and outcome reported. Results: Masses were unilateral (7 hind limb, 3 front limb) and in 8 horses were associated with lameness. In 6 horses, lameness improved by >50% with intrathecal DTFS anesthesia, whereas 2 were less positive but were further improved with perineural anesthesia just proximal to the cyst. Communication between the DFTS and mass was identified in all horses ultrasonographically. Resection of the mass resolved lameness in 7 horses. Histologically (5 specimens), the mass was characterized by a fibrous outer layer without a synovial lining, consistent with a ganglion cyst. Conclusion: The histologic appearance of ganglion cysts suggests that they arise from trauma to the sheath wall and may subsequently be a cause of lameness.  相似文献   
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The primary objective of this study was to characterize Fusarium spp. associated with the economically devastating mango malformation disease (MMD) in Mexico. In all, 142 Fusarium strains were isolated from symptomatic mango inflorescences and vegetative tissues in eight geographically diverse Mexican states from 2002 through 2007. Initially, all the Mexican isolates were screened for genetic diversity using appolymerase chain reaction and random amplified polymorphic DNA markers and were grouped into seven distinct genotypes. Based on results of these analyses, evolutionary relationships and species limits of the genetically diverse MMD-associated Fusarium spp. were investigated using multilocus DNA sequence data and phylogenetic species recognition. Maximum parsimony analyses of a five-locus data set comprising 5.8 kb of aligned DNA sequence data indicated that at least nine phylogenetically distinct Fusarium spp. within the Gibberella fujikuroi species complex are associated with MMD, including one species within the African clade (Fusarium pseudocircinatum), two species within the Asian clade (F. mangiferae and F. proliferatum), and at least six species within the American clade (F. sterilihyphosum and five undescribed Fusarium spp.). Molecular phylogenetic analyses indicate that a novel genealogically exclusive lineage within the American clade was the predominant MMD associate in Mexico. This new Fusarium sp. caused MMD and could be distinguished from all other known species morphologically by the production of mostly sterile, coiled hyphae which are typically associated with sporodochial conidiophores together with unbranched or sparsely branched aerial conidiophores. Koch's postulates were completed for isolates of the new species on nucellar seedlings of mango cv. Ataulfo. This pathogen is formally described herein as F. mexicanum.  相似文献   
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ABSTRACT Fusarium wilt of cotton is a serious fungal disease responsible for significant yield losses throughout the world. Evolution of the causal organism Fusarium oxysporum f. sp. vasinfectum, including the eight races described for this specialized form, was studied using multigene genealogies. Partial sequences of translation elongation factor (EF-1alpha), nitrate reductase (NIR), phosphate permase (PHO), and the mitochondrial small subunit (mtSSU) rDNA were sequenced in 28 isolates of F. oxysporum f. sp. vasinfectum selected to represent the global genetic diversity of this forma specialis. Results of a Wilcoxon Signed-Ranks Templeton test indicated that sequences of the four genes could be combined. In addition, using combined data from EF-1alpha and mtSSU rDNA, the phylogenetic origin of F. oxysporum f. sp. vasinfectum within the F. oxysporum complex was evaluated by the Kishino-Hasegawa likelihood test. Results of this test indicated the eight races of F. oxysporum f. sp. vasinfectum appeared to be nonmonophyletic, having at least two independent, or polyphyletic, evolutionary origins. Races 3 and 5 formed a strongly supported clade separate from the other six races. The combined EF-1alpha, NIR, PHO, and mtSSU rDNA sequence data from the 28 isolates of F. oxysporum f. sp. vasinfectum recovered four lineages that correlated with differences in virulence and geographic origin: lineage I contained race 3, mostly from Egypt, and race 5 from Sudan; lineage II contained races 1, 2, and 6 from North and South America and Africa; lineage III contained race 8 from China; and lineage IV contained isolates of races 4 and 7 from India and China, respectively.  相似文献   
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A zinc-containing intraruminal device has been developed for protecting lambs against facial eczema. The rate of release of zinc from the device has been optimised, and its safety in use established. Under both experimental and farm conditions, the device gave excellent protection against the liver injury associated with facial eczema. The device relies upon erosion for release of zinc, and disappears completely when its charge of zinc has been released, leaving no metal or plastic residue in the rumen. This device has the potential to greatly ameliorate the problem of facial eczema in New Zealand.  相似文献   
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