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1.
A 14-year-old female domestic shorthair cat was presented to Tehran University Veterinary Teaching Hospital for a persistent fever, anorexia, intermittent vomiting, weight loss and weakness. The main clinical signs were pale mucous membranes, dehydration and splenomegaly. The complete blood count and serum biochemistry tests revealed non-regenerative anaemia, thrombocytopenia and increased alkaline phosphatase (ALP) activity. An enzyme-linked immunosorbent assay (ELISA) test for feline leukaemia virus was negative. Blood film and bone marrow examination revealed a large number of immature eosinophils with variable sizes and numbers of faintly azurophilic granules. Cytochemical staining of blood film demonstrated 70% positive cells for ALP activity. Four percent CD34 positive cells were detected by flow cytometry. As eosinophilic leukaemia is difficult to identify by light microscopy, well-defined diagnostic criteria and the use of flow cytometry and cytochemical staining can improve the ability to correctly diagnose this type of leukaemia in cats.  相似文献   
2.
Trunk disease is a major problem on grapevine in Zanjan province, causing serious decline, despite which its aetiology remains unknown. The purpose of this study was to investigate factors involved in grapevine decline in vineyards of Zanjan province. Samples were collected from twigs and branches of grapevines in the region between October and November 2018. Fungal isolates were identified based on morphological characteristics and ITS-rDNA sequence data for selected isolates. The frequency and diversity of the fungal community recovered from grapevines in Darreh Sejin in Zanjan province were higher than in other regions. A total of 112 fungal isolates comprising 22 species were recovered. Phaeoacremonium minimum, Microsphaeropsis olivacea and Kalmusia variispora were identified as the dominant species in the region examined and could be considered the main trunk pathogens of grapevines in Zanjan region. In inoculation tests, M. olivacea was proved to be pathogenic on grapevine for the first time in this study.  相似文献   
3.
Quantification of the interactive effects of nitrogen (N) and water on nitrate (NO3) loss provides an important insight for more effective N and water management. The goal of this study was to evaluate the effect of different irrigation and nitrogen fertilizer levels on nitrate-nitrogen (NO3-N) leaching in a silage maize field. The experiment included four irrigation levels (0.7, 0.85, 1.0, and 1.13 of soil moisture depletion, SMD) and three N fertilization levels (0, 142, and 189 kg N ha−1), with three replications. Ceramic suction cups were used to extract soil solution at 30 and 60 cm soil depths for all 36 experimental plots. Soil NO3-N content of 0-30 and 30-60-cm layers were evaluated at planting and harvest maturity. Total N uptake (NU) by the crop was also determined. Maximum NO3-N leaching out of the 60-cm soil layer was 8.43 kg N ha−1, for the 142 kg N ha−1 and over irrigation (1.13 SMD) treatment. The minimum and maximum seasonal average NO3 concentration at the 60 cm depth was 46 and 138 mg l−1, respectively. Based on our findings, it is possible to control NO3 leaching out of the root zone during the growing season with a proper combination of irrigation and fertilizer management.  相似文献   
4.
Veterinary Research Communications - Accurate estimation of a horse's age based on the condition of the tooth status is necessary as a scientific and artistic technique, which has not been...  相似文献   
5.
Cotton fabrics were dyed with three commercial vat dyes in order to provide camouflage in Vis-NIR regions and imitate reflectance profile of greenish leaves. To investigate the effect of nano particles on camouflage properties of dyed fabric, nano particles of TiO2 were applied on dyed fabrics using pad-dry-cure method. The nano TiO2 padded dyed fabrics were investigated using scanning electron microscopy (SEM). Reflectance curves of coated dyed samples with different concentrations of nano TiO2 were measured. Results showed that in both of the standard shades, nano TiO2 increases the reflectance value in NIR region and with increasing the concentration of nano TiO2, the reflectance curves of samples tend to show the maximum reflection of greenish leaves (deciduous leaves) in NIR region. Chromatic values (CIE1976 L*, a*, and b*) and color difference (according to CIECMC color difference ΔE*cmc (2:1)) of each of the coated samples were measured using the reflection spectrophotometer. By considering the influence of white color of nano TiO2 on green shade of dyed cotton fabrics and increasing the color difference (between coated samples and the standard shades of the 1948 U.S army pattern) in visible range, optimum concentrations of nano TiO2 for development of camouflage properties on cotton fabrics in both NIR and visible region were determined. These values for NATO and forest green shades were 0.75 % and 0.5 %, respectively. Fastness results showed that both of the samples have acceptable color fastness. The effect of washing and exposure to light on camouflage properties of coated dyed fabrics in visible (in term of chromatic values) and NIR region (in term of spectral reflectance) was investigated when those were coated in optimum concentrations of nano TiO2. The results showed that the effect of after treatments (washing and exposure to light) on surface color spectral characteristics and camouflage properties was inconsiderable.  相似文献   
6.
The aim of this work was to evaluate the effective parameters for prediction of the electrospun gelatin nanofibers diameter using artificial neural network (ANN) technique. The various sets of electrospinning process including temperature, applied voltage and polymer and solvent concentrations were designed to produce pure gelatin nanofibers. The obtained results by analyzing Scanning Electron Microscopy (SEM) images indicated that the produced nanofibers diameter was in the range of 85 to 750 nm. Due to the volume of the data, k fold cross-validation method was used for data setting. Data were divided into the five categories and trained and tested using ANN technique. The results indicated that the network including 4 input variables, 3 hidden layers with 10, 18 and 9 nodes in each layers, respectively, and one output layer had the best performance in the testing sets. The mean squared error (MSE) and linear regression (R) between observed and predicted nanofibers diameter were 0.1531 and 0.9424, respectively. The obtained results demonstrated that the selected neural network model had acceptable performance for evaluating involved parameters and prediction of nanofibers diameter.  相似文献   
7.
A wide range of tillage systems have been used by producers in the Corn-Belt in the United States during the past decade due to their economic and environmental benefits. However, changes in soil organic carbon (SOC) and nitrogen (SON) and crop responses to these tillage systems are not well documented in a corn–soybean rotation. Two experiments were conducted to evaluate the effects of different tillage systems on SOC and SON, residue C and N inputs, and corn and soybean yields across Iowa. The first experiment consisted of no-tillage (NT) and chisel plow (CP) treatments, established in 1994 in Clarion–Nicollet–Webster (CNW), Galva–Primghar–Sac (GPS), Kenyon–Floyd–Clyde (KFC), Marshall (M), and Otley–Mahaska–Taintor (OMT) soil associations. The second experiment consisted of NT, strip-tillage (ST), CP, deep rip (DR), and moldboard plow (MP) treatments, established in 1998 in the CNW soil association. Both corn and soybean yields of NT were statistically comparable to those of CP treatment for each soil association in a corn–soybean rotation during the 7 years of tillage practices. The NT, ST, CP, and DR treatments produced similar corn and soybean yields as MP treatment in a corn–soybean rotation during the 3 years of tillage implementation of the second experiment. Significant increases in SOC of 17.3, 19.5, 6.1, and 19.3% with NT over CP treatment were observed at the top 15-cm soil depth in CNW, KFC, M, and OMT soil associations, respectively, except for the GPS soil association in a corn–soybean rotation at the end of 7 years. The NT and ST resulted in significant increases in SOC of 14.7 and 11.4%, respectively, compared with MP treatment after 3 years. Changes in SON due to tillage were similar to those observed with SOC in both experiments. The increases in SOC and SON in NT treatment were not attributed to the vertical stratification of organic C and N in the soil profile or annual C and N inputs from crop residue, but most likely due to the decrease in soil organic matter mineralization in wet and cold soil conditions. It was concluded that NT and ST are superior to CP and MP in increasing SOC and SON in the top 15 cm in the short-term. The adoption of NT or CP can be an effective strategy in increasing SOC and SON in the Corn-Belt soils without significant adverse impact on corn and soybean yields in a corn–soybean rotation.  相似文献   
8.
The article shows results of an international and interdisciplinary project with the title ‘Rainfall and its Erosivity in Ethiopia’. Rainfall variability affects the water resource management of Ethiopia. The influence of rainfall variability on flow regimes was investigated using five gauging stations with data availability from 1982–1997. It was confirmed that the variability in rainfall has a direct implication for surface runoff. Surface runoff declined at most of the gauging stations investigated. Therefore, effective water resource management is recommended for the study area. Future research should focus on watershed management which includes land-use and land cover. The question posed here is whether the variability in rainfall significantly affected surface flow in the study area.  相似文献   
9.
Specimens of Virginia opossums (Didelphis virginiana) in Michigan were examined over 1 year to document the presence of Besnoitia darlingi cysts. Cyst morphology, prevalence, seasonal variation, and tissue sites of isolation were studied. Histology and ultrastructural features of the detected cysts and bradyzoites were consistent with B. darlingi. In the opossums, B. darlingi had intracellular tissue cysts. Tissue cysts had a mean diameter of 560 microm and were separated from the host tissue by a thick (5-20 microm) cyst wall. Overall prevalence of B. darlingi cysts in opossums was 10.9% (15/137). Variations in the prevalence were detected during spring (3/17; 17.6%), summer (10/34; 29.4%), and fall (2/60; 3.3%). No cysts were detected in the specimens examined during winter (0/26; 0%). Numerous B. darlingi cysts were detected in ears, conjunctiva, tongue, abdominal muscles, diaphragm, stomach, heart, liver, kidney, lung, and spleen. Cysts were detected mainly in adult female opossums that were debilitated. Ear was the most frequent organ from which the cysts were reported (10/15; 66.7%) when compared individually with other body tissues (P<0.05).  相似文献   
10.
The aim of this study was to determine the synergistic effects of centrifuged egg yolk (EY) and soybean lecithin on post-thaw Caspian horse sperm motility, morphological abnormalities, and assessment of membrane integrity. The centrifuged EY (CEY) was added at concentrations of 2% and 4% to a defined INRA plus 1.25% soybean lecithin extender used to freeze Caspian horse semen. In this experiment, ejaculates collected from each Caspian horse (n = 4) were divided into three equal aliquots and diluted in CEY 2% (INRA2), 4% (INRA4) supplemented, and without any CEY (INRA0) in INRA plus 1.25% soybean lecithin extender, respectively. Thereafter, samples were frozen and thawed following a standard protocol. Sperm cryosurvival was evaluated in vitro by microscopy assessments of post-thaw sperm motility (by means of computer-assisted semen motility analysis [CASA]), acrosomal and other abnormalities (head, mid-pieces, and tail) and plasma membrane integrity (evaluated by HOST). In Caspian stallion, semen extended with INRA2 had significantly higher CASA motility and CASA progressive motility than those extended with the rest of extenders after freezing and thawing (P < .001). There was no significant difference in path velocity (VAP), VCL, and ALH among three groups (P > .05). For straight line velocity (P < .01) and LIN (P < .001), the highest values were obtained from the INRA4 group. The highest percentages of acrosomal and other abnormalities were found in semen diluted in INRA4 (P < .001). In the group frozen INRA2, the percentage of membrane integrity was significantly higher than that of the other groups (P < .001). The use of CEY 2% in combination with soybean lecithin significantly improved Caspian horse semen freezability.  相似文献   
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