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91.
Relationships between total suspended solids (TSS) and metals (Cu, Pb and Zn) were tested and compared amongst base and high flows of three urbanised catchments in Sydney Estuary, Australia. Significant relationships between TSS and Cu, Pb and Zn were detected for high flows within each catchment; however, no significant relationship was detected for TSS/Zn and TSS/Cu in one of the creeks (Whites Creek) and for TSS/Zn in another (Hawthorne Canal) in 2010 during base flow. Relationships between metals and TSS also varied significantly in locations of intercept and slope between high and base flow and amongst catchments. Spatial variance in TSS/metal relationships were likely caused by specific anthropogenic activities because land uses, meteorology and geology within the study catchments were similar. Results suggest TSS may be used as a surrogate for estimating metal loading in real time for urban catchments, once relationships between metals and TSS were established for individual catchments and for base and high flow conditions. Moreover, no differences in TSS/metal relationships were detected between 2009 and 2010 in Hawthorne Canal during high flow conditions, suggesting that this method of real-time monitoring may be reliable for assessing Cu, Pb and Zn loads during high flows over inter-annual periods. However, long-term consistency of TSS/metal relationships for base flow may need testing since changes in TSS/Zn and TSS/Cu relationships were detected between 2009 and 2010 in Hawthorne Canal. Although irregular discharges to stormwater did not conform to TSS/metal relationships, irregular discharges may be detected in real time by increased flow during dry weather conditions, which may facilitate regulation of these conditions that currently result in potential environmental harm to aquatic biota in Sydney Estuary.  相似文献   
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OBJECTIVE: To determine factors associated with the occurrence of pneumonia after intracranial surgery in dogs. STUDY DESIGN: Retrospective cohort study. Animals-Forty-nine client-owned dogs. METHODS: The medical records of 49 dogs with space-occupying intracranial disease that underwent craniotomy were reviewed. Development of pneumonia after surgery was considered highly likely in 12 dogs (affected dogs) based on clinical signs, including acute dyspnea or coughing in association with typical radiographic findings or abnormal transtracheal wash results. Pneumonia was confirmed in 6 dogs based on necropsy findings. Affected dogs were compared with 37 dogs that did not develop pneumonia (unaffected dogs) subsequent to intracranial surgery. Based on the medical records of affected dogs, determinations were made regarding time between development of pneumonia and surgery, surgical procedure, intracranial lesion type, and intracranial lesion location. Risk factors examined for both affected and unaffected dogs included level of consciousness, body position during the postoperative recovery period, duration of anesthesia, occurrence of vomiting or regurgitation, presence of seizures, cranial nerve deficiencies, and the presence of megaesophagus before and after surgery. We also compared the feeding protocol after surgery for each group. RESULTS: Pneumonia typically occurred within the first week after surgery (median, 6.5 days); however, this was variable (range, 1-96 days). Of the factors that were present within 24 hours before the clinical signs of pneumonia, vomiting or regurgitation and megaesophagus were found to be significant risk factors. Dogs that vomited or regurgitated were 2.71 times more likely to develop pneumonia than dogs that did not. Vomiting or regurgitation occurred in 63% of the dogs that developed pneumonia in this cohort. Dogs with megaesophagus were 9.25 times more likely to develop pneumonia than dogs without megaesophagus. Seven dogs with pneumonia died. Five of these 7 dogs appeared to have died as a direct sequel to pneumonia. CONCLUSION: Dogs undergoing craniectomies for space-occupying intracranial disease may be at higher risk for development of pneumonia due to several factors, including vomiting, regurgitation, and megaesophagus.  相似文献   
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The clinical findings and computed tomographic and magnetic resonance images from four dogs with nasal tumors that invaded the central nervous system were revlewed. There were minimal or no clinical signs related to nasal disease. Brain imaging with magnetic resonance or computed tomography demonstrated antemortem involvement of brain and nasal structures. Magnetic resonance imaging was optimal for demonstrating this involvement and showed more detailed anatomic features of the mass and secondary pathologies attributed to the mass.  相似文献   
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The mitochondrial pathway of apoptosis in vertebrates is dependent on the process of mitochondrial outer membrane permeabilization (MOMP), which leads to the release of proteins from the mitochondrial intermembrane space into the cytosol. "Upstairs" of this event are the Bcl-2 family proteins that regulate and mediate MOMP; "downstairs" is the activation of caspases that orchestrate the dismantling of the cell. In the Connections Map database at Science's Signal Transduction Knowledge Environment (STKE), the pathways that define the mitochondrial pathway of apotosis are illustrated, with the bulk of control occurring "upstairs" of MOMP.  相似文献   
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Magnetic resonance imaging (MRI) was performed on 50 dogs with intracranial neoplasia. The following tumor features were assessed: axial origin, location, shape, growth pattern, MRI signal intensity, evidence for edema, and paramagnetic contrast enhancement. Histologic diagnoses included 5 intracranially invading nasal tumors, 7 pituitary tumors, 22 meningiomas, 6 choroid plexus tumors, 7 astrocytomas, 1 ependymoma, and 2 oligodendrogliomas. Axial origin, site, shape, and growth pattern were important diagnostic characteristics for tumor type. Signal intensity and contrast enhancement pattern allowed further differentiation. Characteristic MRI features that facilitate diagnosis and prognosis were identified. Accurate diagnosis of tumor type based on these features was not always possible because of similarities in MRI appearance for some tumors. Tissue biopsy remains necessary for definitive diagnosis of intracranial tumors.  相似文献   
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A novel herpesvirus was found by molecular methods in samples of Lake Trout Salvelinus namaycush from Lake Erie, Pennsylvania, and Lake Ontario, Keuka Lake, and Lake Otsego, New York. Based on PCR amplification and partial sequencing of polymerase, terminase, and glycoprotein genes, a number of isolates were identified as a novel virus, which we have named Namaycush herpesvirus (NamHV) salmonid herpesvirus 5 (SalHV5). Phylogenetic analyses of three NamHV genes indicated strong clustering with other members of the genus Salmonivirus, placing these isolates into family Alloherpesviridae. The NamHV isolates were identical in the three partially sequenced genes; however, they varied from other salmonid herpesviruses in nucleotide sequence identity. In all three of the genes sequenced, NamHV shared the highest sequence identity with Atlantic Salmon papillomatosis virus (ASPV; SalHV4) isolated from Atlantic Salmon Salmo salar in northern Europe, including northwestern Russia. These results lead one to believe that NamHV and ASPV have a common ancestor that may have made a relatively recent host jump from Atlantic Salmon to Lake Trout or vice versa. Partial nucleotide sequence comparisons between NamHV and ASPV for the polymerase and glycoprotein genes differ by >5% and >10%, respectively. Additional nucleotide sequence comparisons between NamHV and epizootic epitheliotropic disease virus (EEDV/SalHV3) in the terminase, glycoprotein, and polymerase genes differ by >5%, >20%, and >10%, respectively. Thus, NamHV and EEDV may be occupying discrete ecological niches in Lake Trout. Even though NamHV shared the highest genetic identity with ASPV, each of these viruses has a separate host species, which also implies speciation. Additionally, NamHV has been detected over the last 4 years in four separate water bodies across two states, which suggests that NamHV is a distinct, naturally replicating lineage. This, in combination with a divergence in nucleotide sequence from EEDV, indicates that NamHV is a new species in the genus Salmonivirus.

Received April 20, 2015; accepted October 11, 2015  相似文献   

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