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1.
Ultrasonography of the liver was performed in 200 Holstein-Friesian dairy cattle using a 3.5 MHz transducer with a linear array electronic scanner. Liver samples were taken, processed and examined microscopically and the fat occupying rate was calculated. The hepatic ultrasonograms were evaluated according to the presence of bright pattern, dark pattern, deep attenuation, vascular blurring and blurring of edges. Of the 200 animals, 96 had a normal liver, 63 had hydropic degeneration of the liver, 37 had fatty infiltration of the liver, 3 had liver dystrophy and I had hepatic amyloidosis, diagnosed through histopathological examination. Amyloidosis was characterized by bright pattern and blurring of edges. Liver dystrophy had higher percentages of bright pattern and blurring of edges than normal liver. Hydropic degeneration had higher percentages of dark pattern and blurring of edges than normal liver. Fatty infiltration had higher percentages of bright pattern, deep attenuation, vascular blurring and blurring of edges than normal liver. The present results suggest that different ultrasonographic patterns can be observed in various diffuse hepatocellular disorders in dairy cattle  相似文献   
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Tropical Animal Health and Production - Avian influenza virus (AIV) H9N2 subtype is endemic in Iran and causes substantial economic loss to the growing poultry industry within the country. In this...  相似文献   
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The objective of this study was to consider endocannabinoid system as inflammatory markers in bovine endometrium to better understand the role of this system in regulating many of the functions that are related to inflammatory condition. At day 26 post‐partum, fourteen cows were divided into two groups depending on the inflammatory condition: 1‐ subclinical endometritis (n = 7, with purulent or mucopurulent uterine discharge detectable in the vagina) and 2‐ healthy (n = 7, No (muco)) purulent discharge. Blood samples were collected at 26 and 30 days relative to calving to determine plasma tumour necrosis factor (TNF) and lipopolysaccharide‐binding protein (LBP) concentrations; moreover, uterine biopsy was carried out on day 26 post‐partum to measure mRNA abundance of TNF, interleukin‐1B (IL1B), interleukin‐6 (IL‐6), C‐X‐C motif chemokine ligand 8 (CXCL8), endocannabinoid receptor (CNR2), N‐acyl phosphatidylethanolamine phospholipase D (NAPEPLD), fatty acid amide hydrolase (FAAH), N‐acylethanolamine acid amidase (NAAA) and monoglyceride lipase (MGLL) by real‐time PCR. Results showed mean plasma concentrations of TNF and LBP were lower in healthy cows compared to subclinical endometritis cows (p < .05). Relative mRNA expression for NAAA and FAAH was decreased (p < .05), and relative mRNA expression for CNR2 and NAPEPLD increased in cows with subclinical endometritis compared to healthy cows. In conclusion, relative mRNA expression of TNF, IL1B and CXCL8 and plasma concentration of LBP increased during inflammatory condition along with decreased endocannabinoids hydrolyzing enzyme (NAAA and FAAH), increased enzymes that synthesize endocannabinoids (NAPEPLD) and relative gene expression of the endocannabinoid receptor; together, these contribute to increased endocannabinoids levels during inflammation. Overall, we provide evidence that endocannabinoid system is altered in endometrium tissue during inflammation through increased mRNA expression of CNR2 and synthesis enzyme and decreased mRNA expression of hydrolyzing enzymes interfere with pro‐cytokine production and signalling, which may interfere with the onset and progression of inflammation.  相似文献   
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Fire products have been widely identified as germination cues for a number of species from both fire-prone and fire-free ecosystems. However, there is uncertainty about the effects of fire products on seed germination of semi-arid rangeland species. We examined the germination of seven dominant species from Central Zagros rangelands in the semi-arid region of Iran under various heat shock (60, 80 and 120 °C), aerosol smoke, ash and control treatments. Our findings showed that fire products could enhance, inhibit or not affect the seed germination of rangeland species in this area. The germination percentage of Astragalus adscendens increased following 60 °C heat treatment in comparison with the control. The germination of Astragalus verus, Bromus tectorum, B. tomentellus and Phlomis olivieri were increased significantly using smoke treatment (P<0.0001). The seed germination of B. tomentellus and B. tectorum was promoted by ash treatment, whereas the other species exhibited no response or were inhibited by fire products. In addition, smoke treatment shortened the overall germination time of B. tectorum. These findings suggest that fire products affect the germination of several species and can serve as potential tools for understanding the vegetation dynamics and restoration of disturbed semi-arid rangelands.  相似文献   
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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   
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This study was aimed to provide anatomical atlas of the ovine metacarpo/metatarsophalangeal joints using computed tomography (CT) scan and magnetic resonance imaging (MRI), as well as to investigate bone mineral density (BMD) and morphometric features of this joint. The limbs of twenty adult Sanjabi sheep were examined. Imaging was performed using a 16-slice multi-detector CT scanner and a 1.5 Tesla MRI scanner. The obtained images were correlated with corresponding anatomical sections. BMD was measured by Dual Energy X-ray Absorptiometry (DEXA) method. Also morphometric features included distance between metacarpal and metatarsal heads, width of metacarpal and metatarsal head, length, width and the height of the proximal sesamoid bones were measured. In MRI images, compact bones, ligaments and tendons showed less signal intensity (hypointense). The fatty tissue and bone marrow had more signal intensity (hyperintense), but articular cartilage and synovial fluid showed moderate signal intensity. BMD in the left hind limb was significantly higher than other three limbs (p ≤ 0.05). The length of proximal sesamoid bones in left forelimb was higher than right forelimb (p ≤ 0.05). The thickness of proximal sesamoid bones in left limbs was higher than those in their counterparts (p ≤ 0.05). The width of the medial head in the forelimbs was significantly greater than the hind limbs (p ≤ 0.05). The present results might be useful in managing the clinical techniques on this joint. Larger volume of the proximal sesamoid bones and wider medial head in the forelimbs compared to the hindlimbs impel this speculation that the centre of gravity is closer to the forelimbs.  相似文献   
10.
A 4-year-old crossbred Thoroughbred mare was referred to the University of Tehran Veterinary Medical Teaching Hospital for evaluation of a mass in the pelvic cavity. The mare had been partially anorectic and pyrexic. On clinical examination, the mare was thin and depressed, with body temperature of 38°C, a pulse rate of 38 beats/minute, and a respiratory rate of 10 breaths/minute. Palpation per rectum revealed a large, smooth and tense mass in the anterior part of the pelvic cavity. Ultrasound examination confirmed the presence of a soft tissue mass with a thick wall. The inner surface of the mass had a villous-like appearance. The stroma of the mass was mottled, with accumulation of speckled and hypoechoic to slightly hyperechoic fluid. Hormone assays revealed low serum concentration of testosterone. Serum progesterone concentration indicated that active luteal tissue and serum estradiol concentration was 24 pg/ml. On histological examination, the sections from the tumor were composed of oval- or spindle-shaped cells loosely arranged in diffuse sheets or irregularly interlacing fascicles. On the basis of these histological findings, the large tumor mass of the left ovary was considered to be a thecoma. To our knowledge, the details of the clinical, ultrasonographic, endocrinologic, and histologic findings of this tumor in the mare have not been described in the veterinary literature.  相似文献   
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