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21.
In 2017, a PCR‐based survey for Piscine orthoreovirus‐3 (PRV‐3) was conducted in wild anadromous and non‐anadromous salmonids in Norway. In seatrout (anadromous Salmo trutta L.), the virus was present in 16.6% of the fish and in 15 of 21 investigated rivers. Four of 221 (1.8%) Atlantic salmon (Salmo salar L.) from three of 15 rivers were also PCR‐positive, with Ct‐values indicating low amounts of viral RNA. All anadromous Arctic char (Salvelinus alpinus L.) were PCR‐negative. Neither non‐anadromous trout (brown trout) nor landlocked salmon were PRV‐3 positive. Altogether, these findings suggest that in Norway PRV‐3 is more prevalent in the marine environment. In contrast, PRV‐3 is present in areas with intensive inland farming in continental Europe. PRV‐3 genome sequences from Norwegian seatrout grouped together with sequences from rainbow trout (Oncorhynchus mykiss Walbaum) in Norway and Coho salmon (Oncorhynchus kisutch Walbaum) in Chile. At present, the origin of the virus remains unknown. Nevertheless, the study highlights the value of safeguarding native fish by upholding natural and artificial barriers that hinder introduction and spread, on a local or national scale, of alien fish species and their pathogens. Accordingly, further investigations of freshwater reservoirs and interactions with farmed salmonids are warranted.  相似文献   
22.
Medical records of three male and three female callitrichids of four species (Leontopithecus chrysopygus, Leontopithecus rosalia, Callithrix argentata argentata, Callithrix kuhlii) diagnosed with cholelithiasis were reviewed. Ages of affected animals at the time of diagnosis ranged from 2-14 yr. Definitive antemortem diagnosis of cholelithiasis was made in four of the six cases. Chronic weight loss, lethargy, and weakness were seen in all cases. Chronic intermittent diarrhea was seen in three cases. Icterus and abnormal gait were each present in two of the animals. Hematologic and serum biochemical abnormalities included leukocytosis in five cases, elevated bilirubin (direct and indirect) in four cases, and anemia in four cases. Radiographic evidence of choleliths was observed in three cases. Surgical removal of choleliths was successfully performed on two animals. Full necropsies were performed on all cases, and choleliths were believed to contribute to morbidity in all cases. However, inflammatory bowel disease was determined to be the primary cause of weight loss and mortality in at least three animals. All choleliths analyzed were pigment stones, two being primarily composed of cystine.  相似文献   
23.
The purpose of this study was to evaluate short-term adverse effects and determine a safe dosage for vinorelbine (Navelbine)--a new semisynthetic vinca alkaloid--in dogs with malignant tumors. Nineteen dogs were treated with vinorelbine as a 5-minute IV infusion every 7 days at starting dosages ranging from 10 to 20 mg/m2. The median number of treatments per dog was 7 (range, 1-11). The maximum tolerated dosage varied between 15 and 18 mg/m2, and a starting dosage of 15 mg/m2 is recommended. Neutropenia was the dose-limiting toxicity. Although efficacy was a secondary endpoint of this dosage-finding study, 2 dogs with metastatic bronchoalveolar carcinoma experienced a partial response for an overall response rate of 12.5% in 16 dogs with gross measurable disease. Three dogs with microscopic disease were treated (incompletely excised bronchoalveolar carcinoma or lymph node metastatic disease). Two died of pulmonary metastatic disease 113 and 196 days posttreatment, and 1 is still alive after at least 730 days. The well-tolerated toxicity profile and clinical activity observed in dogs with bronchoalveolar carcinoma warrants further investigation.  相似文献   
24.
A 3‐year‐old Marwari mare was presented for evaluation of an irregular, reddish mass protruding from behind the right third eyelid. The mass appeared to arise at the ventral limbal area, involved the perilimbal bulbar conjunctiva and widely extended into corneal tissue. No other ocular or systemic abnormalities were detected at the time of presentation. The mass was surgically removed by lamellar keratectomy, with defocused CO2 laser used as adjunctive therapy to treat the surgical exposed area and its surroundings. Histopathologic evaluation showed sheets of densely packed, well‐differentiated neoplastic mast cells separated by fibrovascular connective tissue. Nuclear staining for Ki‐67 was performed, and an average of 370 cells were positive per 1000 counted cells. Two months postoperatively, the surgical site was filled with flat fibrovascular and pigmented tissue, while the surrounding cornea was transparent with no superficial vascularization around the fibrotic scar. Thirty‐two months after treatment, no recurrence of the neoplasia was reported.  相似文献   
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High-precision 60Fe-60Ni isotope data show that most meteorites originating from differentiated planetesimals that accreted within 1 million years of the solar system's formation have 60Ni/58Ni ratios that are approximately 25 parts per million lower than samples from Earth, Mars, and chondrite parent bodies. This difference indicates that the oldest solar system planetesimals formed in the absence of 60Fe. Evidence for live 60Fe in younger objects suggests that 60Fe was injected into the protoplanetary disk approximately 1 million years after solar system formation, when 26Al was already homogeneously distributed. Decoupling the first appearance of 26Al and 60Fe constrains the environment where the Sun's formation could have taken place, indicating that it occurred in a dense stellar cluster in association with numerous massive stars.  相似文献   
27.
A hallmark of mammalian immunity is the heterogeneity of cell fate that exists among pathogen-experienced lymphocytes. We show that a dividing T lymphocyte initially responding to a microbe exhibits unequal partitioning of proteins that mediate signaling, cell fate specification, and asymmetric cell division. Asymmetric segregation of determinants appears to be coordinated by prolonged interaction between the T cell and its antigen-presenting cell before division. Additionally, the first two daughter T cells displayed phenotypic and functional indicators of being differentially fated toward effector and memory lineages. These results suggest a mechanism by which a single lymphocyte can apportion diverse cell fates necessary for adaptive immunity.  相似文献   
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Enchytraeids are involved both directly and indirectly in decomposition processes and nitrogen mineralization in soil. Their influence is especially important in nitrogen poor ecosystems such as heathland where the enchytraeid species, Cognettia sphagnetorum, is often abundant and playing a significant role in the N-cycling. The objective of this study was to quantify NH4+-N excretion of C. sphagnetorum at different temperatures. The results were combined with investigations of population dynamics during one year to estimate annual NH4+-N excretion of the population of C. sphagnetorum in a dry Danish heath soil. C. sphagnetorum significantly increased its NH4+-N excretion rate with increasing temperature. At 5 °C about 0.5 μg NH4+-N mg dry weight−1 day−1 was excreted increasing to about 3.3 μg NH4+-N mg dry weight−1 day−1 at 20 °C. Average enchytraeid biomass in the field was 2.5-3.5 g dry weight m−2 during cool and wet periods. Dry and warm conditions in May and June, 2008, had a drastic and long-term negative impact on the enchytraeid community. The excretion of NH4+-N by enchytraeids was therefore highest during the cool and moist months despite low temperatures (October 2007-May 2008) and amounted to about 2 mg NH4+-N m−2 day−1 during this period. The estimated annual NH4+-N excretion of the enchytraeid community was approximately 0.3 g N m−2 year−1. The results of the present study and the method described for estimation of N-excretion can increase our understanding of enchytraeids’ role in nitrogen mineralization.  相似文献   
30.
Electronic health records (EHRs) provide clinical learning opportunities through quick and contextual linkage of patient signalment, symptom, and diagnosis data with knowledge resources covering tests, drugs, conditions, procedures, and client instructions. This paper introduces the EHR standards for linkage and the partners-practitioners, content publishers, and software developers-necessary to leverage this possibility in veterinary medicine. The efforts of the American Animal Hospital Association (AAHA) Electronic Health Records Task Force to partner with veterinary practice management systems to improve the use of controlled vocabulary is a first step in the development of standards for sharing knowledge at the point of care. The Veterinary Medical Libraries Section (VMLS) of the Medical Library Association's Task Force on Connecting the Veterinary Health Record to Information Resources compiled a list of resources of potential use at point of care. Resource details were drawn from product Web sites and organized by a metric used to evaluate medical point-of-care resources. Additional information was gathered from questions sent by e-mail and follow-up interviews with two practitioners, a hospital network, two software developers, and three publishers. Veterinarians with electronic records use a variety of information resources that are not linked to their software. Systems lack the infrastructure to use the Infobutton standard that has been gaining popularity in human EHRs. While some veterinary knowledge resources are digital, publisher sites and responses do not indicate a Web-based linkage of veterinary resources with EHRs. In order to facilitate lifelong learning and evidence-based practice, veterinarians and educators of future practitioners must demonstrate to veterinary practice software developers and publishers a clinically-based need to connect knowledge resources to veterinary EHRs.  相似文献   
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