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981.
982.
Pythiosis is a chronic pyogranulomatous infection of the gastrointestinal tract or skin caused by the water borne pathogen Pythium insidiosum. The ultrasonographic features of nine dogs with gastrointestinal pythiosis are reported. The stomach, duodenum, jejunum or colon were affected. All dogs had thickening of the gastrointestinal wall and areas with obliteration of the normal layered appearance. In one dog an eccentric mass was found arising from the serosal surface of the wall of the colon with mild diffuse wall thickening. Regional lymph node enlargement was seen in seven of the nine dogs. One dog had invasion of the pancreas and signs compatible with extrahepatic biliary obstruction. When compared to previous reports of gastrointestinal neoplasia, the features of wall thickening, loss of layering and regional lymphadenopathy are not considered specific for gastrointestinal pythiosis. Histological examination of tissue specimens is required for diagnosis.  相似文献   
983.
The radiographic and ultrasonographic appearance of the normal involution process of the feline postpartum uterus has not been previously described. Six queens were examined to determine the normal radiographic and ultrasonographic appearance of the involuting postpartum uterus. Radiographic and ultrasonographic examinations were performed daily from days one through ten, then on days 12, 14, 18, 24, and 28 postpartum. Radiographically the mean total uterine thickness was 16.5 mm at day one postpartum. By day 14 the mean total uterine thickness was 10.5 mm and by day 24 postpartum the uterus was not radiographically visible. Ultrasonographically at day one postpartum the mean total uterine thickness was 16.6 mm and the mean uterine wall thickness was 2.7 mm. At day 14 postpartum the mean total uterine thickness was 6.2 mm and the mean wall thickness was 2.1 mm. At day 28 postpartum the uterus could still be identified ultrasonographically however individual wall layers were not discernable.  相似文献   
984.
Susan M.  Newell  DVM  MS  John P.  Graham  MVB  MSc  Gregory D.  Roberts  DVM  MS  Pamela E.  Ginn  DVM  Cleatis L.  Chewning  RT    Jay M.  Harrison  MS  Camille  Andrzejewski  BS 《Veterinary radiology & ultrasound》2000,41(1):27-34
Magnetic resonance images of the cranial abdomen were acquired from 15 clinically normal cats. All cats had T1-weighted images, 8 cats had T2-images made and 7 cats had T1-weighted post Gd-DTPA images acquired. Signal intensity measurements for T1, T2, and T1 post contrast sequences were calculated for liver, spleen, gallbladder, renal cortex, renal medulla, pancreas, epaxial muscles, and peritoneal fat. On T1-weighted images the epaxial muscle had the lowest signal intensity, followed by renal medulla, spleen, renal cortex, pancreas, liver and fat, respectively. On T2-weighted images, epaxial muscle had the lowest signal intensity followed by liver, spleen, fat, and gallbladder lumen. Calculations of specific organ percent enhancement following contrast medium administration were made and compared with that reported in humans. A brief review of the potential clinical uses of MR in cats is presented.  相似文献   
985.
986.
987.
Objectives To examine the role of spinal 5‐hydroxytryptamine (5‐HT) binding sites in nociceptive processing in conscious sheep and to study the role of 5‐HT agonists in mediating analgesia. Study design Prospective controlled study. Animals Nine adult healthy female sheep (Swaledale, Swaledale‐cross or Clun Forest) weighing 45–65 kg. Methods Intrathecal (IT) catheters were implanted at the cervical (n = 5) or lumbar (n = 4) level of the spinal cord under general anaesthesia. At least 1 week later, and at 1 week intervals thereafter, the effects of intrathecal Ringer's solution (control), xylazine (100 µg), 5‐HT creatinine sulphate (200, 400 and 800 µg), RU24969 (200 µg), α‐Methyl‐5‐HT and 1‐(3‐Chlorophenyl)‐biguanide (CPBG) on the mechanical nociceptive threshold (MT) were studied. Results were plotted as mean variable versus time curves. Areas under portions of the curves (0–30 and 0–60 minutes) were measured and expressed as mean ± standard error. Differences between values for control and drug trials were examined using the two‐tailed Student's t‐test. Results Baseline values of MT were lower on the hind limbs than on the forelimbs. Intrathecal Ringer's solution did not alter MT in the cervical or lumbar region. Xylazine (100 µg) produced a characteristic elevation in MT between 5 and 60 + minutes. Lumbar IT injection of 5‐HT (800 µg) raised the MT more than cervical injection, while cervical injection of RU24969 (200 µg) raised the MT more than lumbar administration. Cervical IT injection of α‐Me‐5‐HT (500 µg) produced a marked and significant increase in MT while lumbar application had no effect. CPBG (500 µg) injection caused no significant effect on MT with either cervical or lumbar applications. Conclusions The activation of 5‐HT1 and 5‐HT2 receptors particularly at the cervical level appears to be involved in spinal nociceptive processing in the sheep. Clinical relevance These effects, which lasted about 60 minutes, may have an implication in the development of new analgesic strategies for animals.  相似文献   
988.
989.
990.
The objective was to study the role of calpains in meat tenderness. Lambs were fasted for various periods of time to generate differences in meat tenderness and to determine in tandem the expression of calpain 1, calpain 2, calpain 3, and calpastatin. The assumption has been that increased calpain expression associated with an increase in tenderness indicates a role for calpain in the tenderization process and vice versa. Fasting lambs for 1 day caused a significant improvement in longissimus (LD) tenderness compared to the control. Correlations between the tenderness of the LD and the expression of the calpains and calpastatin were significant for calpains 1 and 3 but not for calpain 2 or calpastatin. Consequently, this study supports a role for calpains 1 and 3, but not for calpain 2, in the tenderization of the LD from fasted lambs during post-mortem aging.  相似文献   
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