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991.
A 14-week-old male unilaterally cryptorchid Clumber spaniel was presented for acute lethargy. Physical examination revealed abdominal pain, and a single testis was palpated in the scrotum. Abdominal ultrasound and computed tomography (CT) revealed a poorly vascularized, ovoid structure immediately caudal to the left kidney with scant regional peritoneal effusion. Left intra-abdominal testicular torsion was confirmed at surgery, and routine cryptorchidectomy was performed. The patient recovered uneventfully from anesthesia and surgery.Key clinical message:The most common CT characteristics of testicular torsion were present in this case and correlated well with sonographic findings to allow for rapid, accurate diagnosis and surgical planning of unilateral, non-neoplastic, intra-abdominal cryptorchid testicular torsion in a juvenile dog. Contrast enhanced CT facilitated accurate localization of the undescended testis and evaluation of testicular perfusion and may be a useful alternative to ultrasound for diagnosing testicular torsion, especially in indeterminate cases.  相似文献   
992.
The objectives of the present study were to investigate of GroBiotic®‐A (GBA) on growth, autochthonous intestinal microbiota and haemato‐serological parameters of beluga juvenile. A total of 180 fish (40.82 ± 5.81 g) were fed diets containing graded levels of GBA (0, 5, 10 and 20 g kg?1 diet) for 8 weeks. No significantly differences in body composition, total viable aerobic bacteria, mean cell volume, mean cell haemoglobin, mean cell haemoglobin concentration, neutrophils, eosinophils, monocytes, albumin, glucose, triglyceride, cholesterol, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase and lactate dehydrogenase were detected between treatment groups. The fish fed on 10 and 20 g kg?1 GBA significantly showed higher lactic acid bacteria, final weight, body weight increases, weight gain and lower feed conversion ratio compared with the control and 5 g kg?1 groups. The group fed 20 g kg?1 GBA showed a highly significant difference in condition factor, survival rate, final length, total red and white blood cells, lymphocytes, haematocrit, haemoglobin, total protein, total immunoglobulin and lysozyme activity. The specific growth rate of the treatment groups was significantly elevated compared with the control groups. These results indicated that GBA at level 20 g kg?1 improved growth, welfare and survival of beluga juvenile.  相似文献   
993.
The diversity of fungal endophytes in Sorghum bicolor was investigated in samples collected from 10 different geographical regions of Karnataka state, India. A total of 360 endophytes were isolated from leaf, stem, and root tissues and were assigned to 26 fungal species based on morphology and molecular characterization using ITS sequences. All the endophytes belonged to the phylum Ascomycota. The diversity (Shannon H, 2.57; Simpson_1-D, 0.92) and species richness (Margalef's, 4.68; Menhinick, 3.61) were found to be higher for the endophytes isolated from leaf tissues. The species evenness of the endophytic assemblage was strongly influenced by tissue type, followed by geographical location. The biocontrol potential of isolated endophytes was evaluated against economically destructive sorghum grain mould pathogens such as Fusarium thapsinum, Epicoccum sorghinum, Alternaria alternata, and Curvularia lunata using the dual culture method. Biocontrol potential was exhibited by 26 endophytic isolates, of which Trichoderma asperellum recorded broad-spectrum activity against target pathogens, followed by E. nigrum and A. longipes. Most (82%) endophytes showed plant growth-promoting traits. Biosynthesis of indole-3-acetic acid (IAA) was observed in 84% of isolates, and phosphate solubilization, siderophore production, and cellulase activity was observed in 69%, 23%, and 27% of isolates, respectively. Seeds treated with Tasperellum exhibited a significantly higher seed vigour index (2096), germination percentage (94%), and yield under greenhouse and field conditions. The results were substantiated by the confocal microscopy analysis, which clearly demonstrated the colonization of treated endophyte in root tissues. The present study reveals an ecofriendly approach to explore Tasperellum in sorghum disease management.  相似文献   
994.
Copepodite stage V Calanus finmarchicus were collected at locations on the continental shelf north of Scotland, in the Faroe–Shetland Channel and west of Ireland on six occasions covering winter, spring and summer from October 1993 to June 1995. Oxygen consumption by the overwintering and active spring/summer population of animals was determined at temperatures close to in situ temperatures. Laboratory measurements of oxygen consumption were also made at standardized temperatures (0°C, 5°C, 7°C and 12.5°C) to determine the sensitivity of animals to temperature change in the different seasons. Rates of oxygen consumption were very low (7–30 μmol O2 gC−1 h−1) at in situ temperatures during the winter and early spring and significantly higher (105–219 μmol O2 gC−1 h−1) for the active surface population in May and June. Animals collected from the overwintering population showed no significant response to changes in temperature. Due to the low respiration rates, the calculated rate of decrease in carbon content in diapausing copepodite stage CV was very low (approximately 0.250 μgC day−1). The respiration rates were used to construct a model to estimate survival of the animals with an initial carbon content equivalent to that expected of animals in October. The results showed that in order to survive during winter and have enough energy for moulting and migration to the surface in the spring, these animals have to live at temperatures close to 0°C and be in a diapause state.  相似文献   
995.
为了明确功能微生物菌剂对重度盐碱土壤向日葵农艺性状及微生物群落的影响,采用盆栽试验,研究  相似文献   
996.
997.
采用培养皿法和常规生化方法,研究了新型除草剂唑嘧氯草胺(暂定名,代号:ZJ-2725)的作用机制。结果显示,同时添加20mg/L浓度的缬氨酸、亮氨酸和异亮氨酸能完全恢复唑嘧氯草胺对苘麻芽的生长抑制作用,而添加相同浓度的单一支链氨基酸只能部分消除其抑制作用。离体条件下,随着唑嘧氯草胺浓度的增大,对乙酰乳酸合成酶(ALS)活性的抑制率增加,ALS活性随反应时间的延长而增加,且两者之间符合Michaelis-Meten方程;活体条件下,唑嘧氯草胺对苘麻的ALS也表现出明显的抑制作用,ALS活性明显下降。表明唑嘧氯草胺在植物体内抑制了3种支链氨基酸的生物合成,进而导致植物蛋白质合成受阻而使植物生长受到抑制,ALS即为唑嘧氯草胺的作用靶标。  相似文献   
998.
999.
Background: Ketamine as continuous rate infusion (CRI) provides analgesia in hospitalized horses. Objective: Determine effects of prolonged CRI of ketamine on gastrointestinal transit time, fecal weight, vital parameters, gastrointestinal borborygmi, and behavior scores in healthy adult horses. Animals: Seven adult Thoroughbred or Thoroughbred cross horses, with permanently implanted gastric cannulae. Methods: Nonblinded trial. Random assignment to 1 of 2 crossover designed treatments. Ketamine (0.55 mg/kg IV over 15 minutes followed by 1.2 mg/kg/h) or lactated Ringer's solution (50 mL IV over 15 minutes followed by 0.15 mL/kg/h) treatments. Two hundred 3 × 5 mm plastic beads administered by nasogastric tube before drug administration. Every 2 hours vital parameters, behavior scores recorded, feces collected and weighed, and beads retrieved. Every 6 hours gastrointestinal borborygmi scores recorded. Study terminated upon retrieval of 180 beads (minimum 34 hours) or maximum 96 hours. Nontransit time data analyzed between hours 0 and 34. Results: No significant (P < .05) differences detected between treatments in vital signs or gastrointestinal borborygmi. Significant (P = .002) increase in behavior score during ketamine infusion (0.381) from hours 24–34 compared with placebo (0). Ketamine caused significant delay in passage of 25, 50, and 75% of beads (ketamine = 30.6 ± 5.3, 41.4 ± 8.4, 65.3 ± 13.5 hours versus placebo = 26.8 ± 7.9, 34.3 ± 11.1, 45.8 ± 19.4 hours), and significant (P < .05) decrease in fecal weight from hours 22 (12.6 ± 3.2 versus 14.5 ± 3.8 kg) through 34 (18.5 ± 3.9 versus 12.8 ± 6.4 kg) of infusion. Conclusions and Clinical Importance: Ketamine CRI delayed gastrointestinal transit time in healthy horses without effect on vital parameters.  相似文献   
1000.
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