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121.
Gonzalez M Miglioranza KS Aizpún de Moreno JE Moreno VJ 《Journal of agricultural and food chemistry》2003,51(5):1353-1359
Organochlorine pesticides (OCPs) were quantified by GC-ECD in tomato (Lycopersicon esculentum) during a vegetation period. Plants were harvested at 15, 60, and 151 days after seed germination. Leaves, stem, roots, and fruit (peel and flesh) were analyzed separately. The results showed that tomato plants were able to accumulate OCPs from soils, and a trend to reach the equilibrium among tissues at mature stages was also observed. Endosulfans comprised the main OCP group, probably due to its spray during summer months in the surrounding areas. Banned pesticides such as DDTs, heptachlor, and dieldrin were found. OCPs levels in the fruit were below the maximum residues limits (MRL) considered by the Codex Alimentarius. DDE/DDT and alpha-/gamma-HCH ratios of <1 would indicate recent inputs of DDT and lindane in the environment. The occurrence of OCPs in the study farm, where agrochemicals have never been used, is a result of atmospheric deposition of those pesticides. 相似文献
122.
Shankaramurthy Channabasappa Julia Ferguson Baljit Singh 《Canadian journal of veterinary research》2014,78(3):176-182
Retinoids play an important role in lung development and immune response. The effects of retinoids are mediated through 2 families of retinoid receptors: retinoic acid receptors (RARs) and retinoid X receptors (RXRs), with alpha (α), beta (β), and gamma (γ) subtypes in each family. To date, no data exist on the expression pattern of retinoid receptors in lungs of cattle, dogs, and pigs. Because of the biomedical importance of retinoid receptors in inflammation and immune responses, Western blot, immunohistology, and immunoelectron microscopy were used to determine the expression of retinoid receptors in normal lungs of cattle, dogs, and pigs (n = 2 for each species). Western blot showed expression of all 6 retinoid receptor subtypes in pig lungs. Immunohistology data indicated differential expression of retinoid receptors in airway epithelium, vascular endothelium, alveolar/septal macrophages, and alveolar septum in all 3 species. Electron microscopy showed nuclear localization of retinoid receptors in neutrophils and pulmonary intravascular macrophages. Retinoic acid receptors (RAR) α subtype were localized in cytoplasmic vacuoles of pig monocytes. These data indicate constitutive expression of retinoid receptors in the lungs of cattle, dogs, and pigs. 相似文献
123.
Troan BV Perelygina L Patrusheva I Wettere AJ Hilliard JK Loomis MR Voe RS 《Journal of the American Veterinary Medical Association》2007,231(12):1878-1883
CASE DESCRIPTION: A 6.5-year-old female eastern black and white colobus monkey (Colobus guereza) was evaluated after acute onset of ataxia and inappetence. CLINICAL FINDINGS: The monkey was ataxic and lethargic, but no other abnormalities were detected via physical examination, radiography, or clinicopathologic analyses. During the next 2 days, the monkey's clinical condition deteriorated, and its WBC count decreased dramatically. Cytologic examination of a CSF sample revealed marked lymphohistiocytic inflammation. TREATMENT AND OUTCOME: Despite supportive care, the monkey became apneic; after 20 hours of mechanical ventilation, fatal cardiac arrest occurred. At necropsy, numerous petechiae were detected within the white matter tracts of the brain; microscopic lesions of multifocal necrosis and hemorrhage with intranuclear inclusions identified in the brain and adrenal glands were consistent with an acute herpesvirus infection. A specific diagnosis of herpesvirus papio-2 (HVP-2) infection was made on the basis of results of serologic testing; PCR assay of tissue specimens; live virus isolation from the lungs; and immunohistochemical identification of the virus within brain, spinal cord, and adrenal gland lesions. Via phylogenetic tree analysis, the colobus HVP-2 isolate was grouped with neuroinvasive strains of the virus. The virus was most likely transmitted to the colobus monkey through toys shared with a nearby colony of baboons (the natural host of HVP-2). CLINICAL RELEVANCE: To the authors' knowledge, this is the first reported case of natural transmission of HVP-2 to a nonhost species. Infection with HVP-2 should be a differential diagnosis for acute encephalopathy in primate monkeys and humans, particularly following exposure to baboons. 相似文献
124.
Elena A. Mikhailova Donald Hagan Julia Sharp Brian Ritter Roxanne Stiglitz Veeander Mealing 《Communications in Soil Science and Plant Analysis》2017,48(9):1068-1077
Japanese stiltgrass (Microstegium vimineum), an exotic invasive plant, is native to Southeast Asia. This study was conducted to determine the chemical composition of Japanese stiltgrass as well as soil and landscape characteristics that correlate with invasion of Japanese stiltgrass around Lake Issaqueena in the upper Piedmont of South Carolina. Geographic Information Systems (GISs) and Light Detection and Ranging (LiDAR) were used to determine the spatial pattern of invasion with respect to the aspect, slope, canopy cover, soils, and distance to roads and trails. Japanese stiltgrass was distributed on both sides of Lake Issaqueena in Pacolet and Madison soil map units (Fine, kaolinitic, thermic Typic Kanhapludults) on the average slopes of 21%, but it was particularly common on the eastern shore of the lake in low-lying wet and shaded areas (mean canopy cover 51%). In addition, invasion by Japanese stiltgrass was correlated with the proximity to roads and trails. Plant tissue analysis revealed many differences in the distribution of macronutrients, macrominerals, and micronutrients in the leaves, stems, and roots of Japanese stiltgrass, although those differences were not always statistically significant. Concentrations of nitrogen (N), phosphorus (P), and calcium (Ca) were the highest in leaves while zinc (Zn) concentrations were the highest in stems and concentrations of magnesium (Mg), copper (Cu), manganese (Mn), iron (Fe), and sodium (Na) tended to be higher in roots. Carbon (C), sulfur (S), and potassium (K) concentrations were generally higher in above-ground tissues versus roots. Soil chemical analysis revealed no statistical differences between control and invaded plots. Our findings suggest that watershed areas surrounding lakes may be particularly susceptible to the invasion of Japanese stiltgrass due to their microclimates, low-lying wet pathways for seed distribution and recreational uses. 相似文献
125.
Morrow EM Yoo SY Flavell SW Kim TK Lin Y Hill RS Mukaddes NM Balkhy S Gascon G Hashmi A Al-Saad S Ware J Joseph RM Greenblatt R Gleason D Ertelt JA Apse KA Bodell A Partlow JN Barry B Yao H Markianos K Ferland RJ Greenberg ME Walsh CA 《Science (New York, N.Y.)》2008,321(5886):218-223
To find inherited causes of autism-spectrum disorders, we studied families in which parents share ancestors, enhancing the role of inherited factors. We mapped several loci, some containing large, inherited, homozygous deletions that are likely mutations. The largest deletions implicated genes, including PCDH10 (protocadherin 10) and DIA1 (deleted in autism1, or c3orf58), whose level of expression changes in response to neuronal activity, a marker of genes involved in synaptic changes that underlie learning. A subset of genes, including NHE9 (Na+/H+ exchanger 9), showed additional potential mutations in patients with unrelated parents. Our findings highlight the utility of "homozygosity mapping" in heterogeneous disorders like autism but also suggest that defective regulation of gene expression after neural activity may be a mechanism common to seemingly diverse autism mutations. 相似文献
126.
OBJECTIVE: To describe use of the scrotum as a pedicle flap to cover defects created by tumor excision in the perineum or caudal and medial aspect of the thigh. STUDY DESIGN: Clinical study. ANIMALS: Three dogs. METHODS: After tumor excision and prescrotal castration, an incision was made around the base of the scrotum, leaving a pedicle on the side opposite the skin defect. After removal of the tunica dartos and abdominal fascia, the scrotal skin was stretched and shaped to the defect, then sutured in position with a simple interrupted pattern. Bandages that were changed every 48 hours compressed the flaps, and healing was observed until sutures were removed. RESULTS: Two dogs had first intention healing in 15 days, whereas 1 dog developed necrosis of 10% of the flap, and this area healed by second intention. CONCLUSION: In male dogs, the scrotal skin can be used as a pedicle flap for reconstructive surgery of wounds in the perineum and the proximomedial and caudal aspect of the thigh. CLINICAL RELEVANCE: The perineal region remains a surgical challenge because of the lack of the available skin for reconstruction of surgical wounds. The scrotal skin should be considered for use as a transposition flap to cover skin defects in this region. 相似文献
127.
Julia B. Ewaschuk Jonathan M. Naylor Manuel Chirino-Trejo Gordon A. Zello 《Canadian journal of veterinary research》2004,68(4):249-253
Diarrhea is a common occurrence in neonatal calves. Several veterinary probiotics claiming to prevent or treat calf diarrhea are available, but have not been well studied. This study assessed the capability of Lactobacillus rhamnosus strain GG (LGG) to maintain viability in the gastrointestinal tract of calves. We also determined whether LGG can be administered in an oral rehydration solution (ORS) without compromising the efficacy of the ORS or the viability of LGG, and whether LGG produces D-lactate or not. To investigate the intestinal survival of LGG, 15 calves were randomized into 3 groups and LGG was administered orally with their morning milk feeding on 3 consecutive days at a low (LD), medium (MD), or high (HD) dosage. Fecal samples were collected on days 0 (control), 1, 2, 3, 5, and 7 and incubated for 72 h on deMan, Rogosa, Sharpe agar. Twenty-four hours after the 1st feeding, LGG was recovered from 1 out of 5 calves in the LD group, 4 out of 5 calves in the MD group, and 5 out of 5 calves in the HD group. To determine if LGG caused the glucose levels in the ORS to drop below effective levels, 1.5 L of the ORS was incubated with LGG for 2 h at 37 degrees C and the glucose concentration was measured every 20 min using a glucose meter. This ORS was then further incubated for 10 h and aliquots analyzed by high performance liquid chromatography to determine if D-lactate was produced by LGG. Glucose concentrations did not change over the 2 h of incubation, and no D-lactate was produced after 48 h. The LGG maintained viability in ORS. Therefore, this study demonstrated that LGG survives intestinal transit in the young calf, produces no D-lactate, and can be administered in an ORS. 相似文献
128.
We argue that thematic resolution, i.e., the level of categorical detail of a thematic map expressed by the number of classes
included in the map legend, is an inherent component of the scale at which a landscape is analyzed. Changing the number of
classes can change the configuration of the patch mosaic as much as changing the grain does. We address recent calls in this
and other journals to deepen research in this topic. In particular, we report how thematic resolution affects the patchiness
of mosaics representing natural landscapes, which have seldom been studied in this respect. We selected seven 50 × 50 km landscapes
within national parks, each representative of a world biome. We applied an object-based unsupervised classification to Landsat
TM imagery of these landscapes using increasing numbers of classes, between 2 and 50, and derived curves of mean patch size
and patch density for each site. Our results are consistent with previous findings in that the patchiness of output mosaics
increases monotonically with increasing thematic resolution, with a higher rate of increase up to eight classes that declines
until it becomes roughly constant for more than 16 classes. However, this constant rate of increase is still considerable,
meaning that, at least for natural landscapes, there is no threshold beyond which the patch-mosaic model is independent of
the conceptual filter applied. This dependence on human fiat calls for re-thinking the patch-mosaic paradigm. 相似文献
129.
Lauren J. Harris Kelly L. Hughes E. J. Ehrhart Julia D. Labadie Janna Yoshimoto Anne C. Avery 《Veterinary and comparative oncology》2019,17(3):253-264
T‐cell lymphomas (TCL) are a diverse group of neoplasms with variable diagnostic features, pathophysiologies, therapeutic responses and clinical outcomes. In dogs, TCL includes indolent and aggressive tumours such as T‐zone lymphoma (TZL) and peripheral T‐cell lymphoma (PTCL), respectively. Delineation of molecular subtypes and investigation into underlying pathophysiologies of aggressive TCLs remains inadequate. We investigate the correlations between flow cytometry and histopathology of 73 cases of nodal TCL. The majority of cases (82.2%) were characterized as CD4+ TCL by flow cytometry. Fewer cases were classified as CD8+ TCL (6.8%) or CD4?CD8? TCL (11.0%). All cases, regardless of immunophenotype, exhibited conserved histologic features consistent with the WHO classification of PTCL. Histologic subsets of PTCL corresponding to immunophenotypic features were not identified. Neoplastic cell size determined by flow cytometry correlated significantly with mitotic rate. RNA‐seq was performed on a subset of CD4+ PTCL cases (n = 6) and compared with sorted control CD4+ T‐cells. The gene expression pattern of CD4+ PTCL was similar between all cases regardless of breed. PTCL was enriched in pathways representing G‐coupled protein receptor signalling, extracellular matrix remodelling and vascular development, immune signalling and mitotic activity. Furthermore, global gene expression changes were consistent with downregulation of PTEN signalling and upregulation of the MTOR‐PI3K‐ATK axis. In this study, we evaluated the correlations between flow cytometry, histopathology and gene expression within a large cohort of nodal TCLs. We further demonstrate the ability of flow cytometry to identify a subtype of T‐cell lymphoma, CD4+ PTCL, with a uniform histomorphology and gene expression profile. 相似文献
130.
Martin Kohler Julia Sohn Gregor Nägele Jürgen Bauhus 《European Journal of Forest Research》2010,129(6):1109-1118
To investigate whether drought tolerance of individual trees can be increased through the provision of more growing space,
trees from a thinning experiment were analysed for reductions in radial growth during drought years and their subsequent recovery.
Tree-ring widths were quantified on increment cores as well as stem discs of 32 trees from stands of a thinning trial established
in 1974 in 27-year-old spruce stands in the Alpine Foreland of Southwest Germany. Three different thinning regimes of the
trial were selected for this study: unthinned control (8 trees), moderate (13 trees) and heavy thinning (11 trees) intensities.
All trees sampled were of a co-dominant to dominant canopy status. The standardisation of growth data was carried out using
the software program ARSTAN (University of Arizona). For the year 1976—a widespread and severe drought year in Germany—we
found year ring widths were not reduced compared to those of the pre-drought years for all treatments. However, we observed
the formation of false year rings and resin ducts for this year in all trees investigated. The drought events in 1992 and
2003 led to severe growth depressions in the year of the drought event in all trees, regardless of previous thinning regimes.
However, the resilience—the recovery of basal area growth in subsequent years—was significantly more rapid in trees from heavily
thinned stands, even if the drought event occurred more than 10 years after the last thinning intervention. This indicates
a shorter stress period for trees with more growing space, which may reduce the susceptibility to secondary pathogens or pest
species such as bark beetles. 相似文献