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71.
BACKGROUND: Although the histopathologic features of necrotizing meningoencephalitis (NME) have been described previously, little information is available concerning the signalment, geographic distribution, seasonal onset, treatment, and survival of affected dogs. ANIMALS: Sixty Pugs with NME and 14 contemporaneous control Pugs with other intracranial diseases (non-NME group). METHODS: Pugs that were euthanized or died because of intracranial disease were prospectively obtained. All dogs had necropsy, histopathology, and testing for various infectious diseases and were subsequently divided into NME and non-NME groups. Signalment, geographic distribution, seasonal onset, treatment, and survival were compared between groups. RESULTS: In Pugs with NME, median age at onset of clinical signs was 18 months (range, 4-113 months). A greater proportion of female dogs were present in the NME group (40/60) compared with the control group (6/14). Pugs with NME had a significantly lower mean weight (7.81 kg) than control Pugs (9.79 kg) (P= .012). Mean survival in Pugs with NME was 93 days (range, 1-680 days), with dogs receiving any form of treatment living significantly longer than those that were not treated (P= .003). Anticonvulsive drugs were the only treatment significantly associated with longer survival (P= .003). CONCLUSIONS AND CLINICAL IMPORTANCE: NME appears to be a common cause of intracranial signs in Pugs, based on the high proportion of NME dogs reported in this population. Pugs with NME are most commonly young adult female dogs. Although further investigation is needed to determine the optimal treatment of NME, anticonvulsive drugs appear to beneficially affect duration of survival.  相似文献   
72.
OBJECTIVE: To identify the optimum pooling rate for pooled faecal culture (PFC) as a diagnostic tool in bovine Johne's disease control, for detection of cattle shedding low concentrations of Mycobacterium avium subsp paratuberculosis (Map). METHOD: Thirteen target animals were selected by delayed growth of Map from initial individual radiometric faecal cultures (first growth index at 5 weeks or later). A procedure based on radiometric culture and IS900 polymerase chain reaction and restriction endonuclease analysis confirmation was then used for PFC. RESULTS: Eight samples (stored for up to 17 months at -80 degrees C) yielded Map on subsequent culture, either from undiluted faeces or those mixed with normal cattle faeces at dilution rates from 1 in 5 to 1 in 50. From a regression equation, culture-positive animals were considered to be shedding relatively low levels of Map (< 6 x 10(4)/g of faeces). Pooling dilutions of more than 1 in 5 reduced PFC sensitivity. A minimum incubation period of 10 weeks at a dilution of 1 in 5 is recommended to detect such infected cattle. This pooling rate in radiometric culture is probably capable of detecting cattle shedding < or = 5 x 10(3) Map organisms/g of faeces, representing an estimated inoculum per culture vial of fewer than 20 viable organisms. CONCLUSION: Map was detected in more than 50% of the stored faecal samples from cattle shedding low concentrations of the organism. A pooling rate of 5 samples per pool is required to reliably detect infected low-shedder cattle using PFC based on radiometric culture.  相似文献   
73.
Human patients with atopic dermatitis (AD) commonly exhibit IgE reactivity to cutaneous self-antigens. The presence of serum IgE autoantibodies appears to correlate with disease severity, and it is suspected to reflect or contribute to tissue damage. The objective of this study was to determine whether IgE autoantibodies specific for cutaneous antigens could be detected in the serum of dogs with AD. Serum was collected from 19 dogs with untreated moderate to severe AD and four specific-pathogen free (SPF) dogs. Indirect immunofluorescence was performed using normal canine skin collected at four different locations (concave ear, nose, medial thigh and lateral thorax), while Western immunoblotting was done using normal canine ear pinna epidermal and dermal extracts and reducing conditions. In both methods, IgE was detected using a monoclonal antibody specific for heat stable epitopes of canine IgE. At 1:10 dilution, specific IgE autoantibodies against cutaneous autoantigens were not detected, with either method, in AD and SPF canine sera. Either IgE autoreactivity is not associated with moderate to severe AD in dogs, or the methods employed herein were not sensitive enough to permit IgE autoantibody detection.  相似文献   
74.
Ganglioneuromas are complex tumors that arise in peripheral ganglia and are composed of well-differentiated neurons, nerve processes, Schwann cells, and enteric glial cells. The term ganglioneuromatosis (GN) denotes a regional or segmental proliferation of ganglioneuromatous tissue. This report describes an 8-year-old mixed breed horse with GN in a 25-cm segment of small colon. Grossly, the lesion consisted of numerous sessile to pedunculated nodules extending from the serosal surface. Histologic examination revealed the nodules to consist of fascicles of spindle-shaped cells consistent with Schwann cells, clusters of neurons, supporting enteric glial cells, and thick bands of perineurial collagen. Most of the nodules coincided with the location of the myenteric plexus and extended through the outer layer of the tunica muscularis to the serosal surface. Neuronal processes were demonstrated within the lesion with electron microscopy. With immunohistochemistry neurons were positive for neuron specific enolase (NSE) and S-100 and the Schwann cells and enteric glial cells were positive for S-100 and glial fibrillary acidic protein (GFAP). The pathogenesis of GN is poorly understood. GN, although rare, should be included in the differential diagnosis of gastrointestinal tumors in the horse.  相似文献   
75.
The 1AL.1RS wheat-rye chromosomal translocation originally found in ‘Amigo’ wheat possesses resistance genes for stem rust, powdery mildew and greenbug biotypes B and C, but also has a negative effect on wheat processing quality. Recently, a second 1AL.1RS translocation carrying Gb6, a gene conferring resistance to greenbug biotypes B, C, E, G and I, was identified in the wheat germplasm line ‘GRS1201′. Protein analytical methods, and the DNA polymerase chain reaction were used to identify markers capable of differentiating the 1RS chromosome arms derived from ‘Amigo’ and ‘GRS1201′. The secalin proteins encoded by genes on 1RS chromosome arms differed in ‘Amigo’ and ‘GRS1201′. A 70 kDa secalin was found in the ‘Amigo’1AL.1RS, but did not occur in the ‘GRS1201’1AL.1RS. Polymorphisms detected by PCR primers derived from a family of moderately repetitive rye DNA sequences also differentiated the two translocations. When ‘GRS1201’was mated with a non-1RS wheat, no recombinants between 1RS markers were observed. In crosses between 1RS and non-1RS parents, both DNA markers and secalins would be useful as selectable markers for 1RS-derived greenbug resistance. Recombination between 1RS markers did occur when 1RS from ‘Amigo’ and 1RS from ‘GRS1201’were combined, but in such intermatings, the molecular markers described herein could still be used to develop a population enriched in lines carrying Gb6. No differences in grain yield or grain and flour quality characteristics were observed when lines carrying 1RS from ‘Amigo’ were compared with lines with 1RS from ‘GRS1201′. Hence, differences in secalin composition did not result in differential quality effects. When compared with sister lines with 1AL.1AS derived from the wheat cultivar ‘Redland’, lines with ‘GRS1201’had equal grain yield, but produced flours with significantly shorter mix times, weaker doughs, and lower sodium dodecyl sulphate sedimentation volumes.  相似文献   
76.
McKay  G.  Porter  J. F.  Prasad  G. R. 《Water, air, and soil pollution》1999,114(3-4):423-438
The ability of five low cost adsorbents – rice husk, cotton, bark, hair and coal – to adsorb two basic dyes, namely, Safranine and Methylene Blue, has been studied. Equilibrium isotherms have been determined and analysed using the Langmuir equations. The monolayer saturation capacities for Safranine are 1119, 838, 875, 190 and 120 mg g-1adsorbent and for Methylene Blue are 914, 312, 277, 158 and 250 mg g-1adsorbent for bark, rice husk, cotton waste, hair and coal respectively. A limited number of fixed bed column studies have been performed and the bed depth service time for each dye-adsorbent system has been determined.  相似文献   
77.
We have previously reported that supplementation with Saccharomyces cerevisiae fermentation products (SCFP) ameliorates clinical signs and lung pathology following experimental bovine respiratory syncytial virus (BRSV) infection in preweaned dairy calves. The objectives of this study were to determine the effect of SCFP supplementation on the metabolic and endocrine responses, and disease outcome of a viral–bacterial coinfection in preweaned calves. Twenty-seven, 1- to 2-d-old Holstein-Angus cross calves were enrolled in the study; one SCFP calf was removed from the trial during the pre-challenge phase due to complications from nephritis. Calves were assigned to two treatment groups: control or SCFP-treated, base milk replacer with 1 g/d SCFP (Smartcare, soluble formula) and calf starter top dressed with 5 g/d SCFP (NutriTek, insoluble formula). Calves were infected with BRSV on day 21, followed 6 d later by intratracheal inoculation with Pasteurella multocida (PM). Calves were euthanized on day 10 post-viral infection. Calves receiving SCFP had reduced thoracic ultrasonography scores on day 7 post-viral infection (P = 0.03) and a tendency toward reduced scores on day 10 post-viral infection (P = 0.09). Calves receiving SCFP also had less severe lung pathology scores at necropsy (P = 0.06). No differences between treatments were observed in lung viral loads (P = 0.48) or bacterial lung recovery (P = 0.34); however, there was a distinction in the lung location for PM recovery, with PM isolated more frequently from the cranial lobes in SCFP-treated calves, but more frequently from the caudal lobes of control calves. Calves treated with SCFP tended (P = 0.07) to have higher serum IL-6 concentrations following the coinfection. Calves treated with SCFP had lower concentrations of serum nonesterified fatty acids and beta-hydroxybutyric acid compared with controls following experimental challenge (P = 0.03 and P = 0.08, respectively), suggesting metabolic changes favoring growth and development. There were no differences between groups in gene expression of insulin receptor, insulin-like growth factor 1 (IGF-1), IGF-1 receptor (IGF-1R), growth hormone receptor, or haptoglobin in the liver. Results from this study suggest that supplementing with SCFP may moderate the impact of a respiratory viral–bacterial coinfection on preweaned calves through metabolic and immune modifications.  相似文献   
78.
Effects of formulation on the textural stability of intermediate‐moisture, flour‐based, “jerky”‐type extrudates were assessed. Potato‐based extrudates containing various particulate‐meat concentrations and different plasticizers (sucrose, fructose, glycerol, and glucose) were produced and subjected to accelerated storage for three weeks. The elastic modulus of the samples was measured before storage and then weekly. The relative fluidity and moisture mobility of the specimens were assessed by dynamic mechanical spectrometry (DMS), electron spin resonance (ESR), and nuclear magnetic resonance (NMR). Samples were also evaluated by fluorometry and X‐ray diffraction to determine the extent of browning reaction and degree of molecular ordering, respectively. While elastic modulus increased appreciably during storage, firming was progressively reduced by entrained meat content and also by plasticizers, especially glycerol; plasticized and meat‐containing samples had correspondingly lower tan δ peak temperatures as measured by DMS. Textural results were also in keeping with fluidity and local viscosity as assessed by ESR measurements. NMR T1 relaxation values, reflecting moisture mobility, increased during storage. Diffraction spectra were consistent with published observations of hydrated starch, suggesting that water may have been released due to increased association of proteinaceous constituents. Fluorescence measurements confirmed moderate Maillard browning in all samples and significant chlorogenic browning in glucose‐containing samples, although these effects were unrelated to degree of firming. It was concluded that textural stability was optimized by interruption of the matrix by dispersed meat or by plasticization by low molecular weight constituents.  相似文献   
79.
Coast redwood (Sequoia sempervirens), a western North American conifer of ancient lineage, has a paradoxical combination of late-successional characteristics and strong adaptations to disturbance. Despite its shade tolerance and heavy dominance of the canopy on many sites, redwood saplings are uncommon in upland old-growth stands. Information needed to ensure the conservation of old-growth redwood forests has been limited. In this review paper, we integrate evidence on redwood biology with data on the historic and modern disturbance regimes to help clarify the degree to which key attributes of redwood forests may have been dependent upon periodic disturbance. Available evidence suggests that episodes of fire, flooding, and slope failure prior to European settlement were frequent but predominantly of low to moderate severity and extent, resulting in broadly uneven-aged forests. The majority of fires prior to European settlement were apparently of human origin. Frequency and severity of the major disturbance agents have been radically changed in modern times. Fires have been largely excluded, and flooding has been altered in ways that have often been detrimental to old-growth redwoods on alluvial terraces. However, because of the apparent anthropogenic origin of most presettlement fires, the long-term evolutionary role of fire for coast redwood is ecologically ambiguous. With fire exclusion, redwood possibly could be displaced to some extent on upland sites by increasing abundance of fire-sensitive competitors. Alternatively, redwood may be able to maintain dominance by vegetative sprouting and new seedling establishment on root-wad mounds, fallen logs, and on soil exposed by slope failure. Future research priorities are suggested that will help resolve some of the current ambiguities.  相似文献   
80.
Melatonin implants were used to override natural melatonin rhythm in groups of juvenile Atlantic salmon, Salmo salar, raised at simulated natural photoperiod (SNP) and constant light (LL) from mid-March until end of August. The experiment contained also both sham control (with non-melatonin implants) and control (no implants). No differences were found in the experimental variables between these two control groups. Growth and food intake were negatively affected by melatonin implantation. Overall, higher GH levels were observed in the SNP melatonin-implanted group, whereas no differences in GH levels were seen between the SNP control, LL control, or the LL melatonin-implanted groups. Highest food intake was seen in the LL control group. No differences in food intake were recorded between the LL melatonin-implanted and SNP control groups. Gill Na+, K+, ATPase (NKA) activity was influenced by time as well as the interaction between photoperiod and time. No differences in gill NKA activity or plasma chloride levels following transfer to seawater were seen between the groups with melatonin implants and their controls. Based on the present results, it seems apparent that melatonin does play a role in regulating food intake and growth in Atlantic salmon smolts.  相似文献   
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