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51.
Seeds of 49 accessions of corn (Zea mays ssp. mays), 9 accessions of teosinte (Zea species that are thought to be ancestors and probable progenitors to corn), and 3 accessions of Job's tears (Coix lacryma), obtained from a germplasm repository, were ground and extracted with hexane. Whole kernel oil yields and levels of four phytonutrients (free phytosterols, fatty acyl phytosterol esters, ferulate phytosterol esters, and gamma-tocopherol) in the oils were measured. Among the seeds tested, oil yields ranged from 2.19 to 4.83 wt %, the levels of ferulate phytosterol esters in the oil ranged from 0.047 to 0.839 wt %, the levels of free phytosterols in the oil ranged from 0.54 to 1.28 wt %, the levels of phytosterol fatty acyl esters in the oil ranged from 0.76 to 3.09 wt %, the levels of total phytosterols in the oil ranged from 1.40 to 4.38 wt %, and the levels of gamma-tocopherol in the oil ranged from 0.023 to 0.127 wt %. In general, higher levels of all three phytosterol classes were observed in seed oils from accessions of Zea mays ssp. mays than in seed oils from accessions of the other taxonomic groups. The highest levels of gamma-tocopherol were observed in teosinte accessions.  相似文献   
52.
The distribution of oxytetracycline (OTC) in male and female Macrobrachium rosenbergii was examined after the prawns had been given medicated feed containing OTC at levels of 2.5 and 5.0 g/kg of feed for 1 week and nonmedicated feed thereafter. OTC levels in the heads of both male and female prawns were consistently higher than in the muscles. Batches of both male and female prawns treated with higher dosages had significantly higher OTC residues in both head and muscle tissues than the batches treated with lower dosages. During treatment, peak concentrations in the head and muscle from each group were reached within 4-6 days. After drug treatment ceased, 13 days for the head and 10 days for the muscle were required to reduce OTC residues to safe levels in all batches of both sexes and dosages. In practice, to account for variations in water temperature, drug dosage, duration of therapy, and other environmental conditions, a withdrawal period of 21 days is recommended.  相似文献   
53.
The effect of microgravity on functional development of the small intestine of Japanese quails incubated for 2-3 d and hatched on the orbital station MIR was examined. After 5 d of space flight duodenal and jejunal alkaline phosphatase (AP) activity of the experimental group was compared with the AP activity in quails of the same age hatched on the Earth (laboratory controls). Short-term microgravity leading to decreased food intake resulted in significant increase of AP activity in both duodenal and jejunal enterocytes (P<0.001) of the experimental quails. The results suggest that increased AP activity probably reflects the delayed functional development of the small intestine as a consequence of inappropriate food intake during non-physiological conditions of space flight.  相似文献   
54.
Pyonephrosis refers to suppurative destruction of the parenchyma of the kidney with complete or nearly complete loss of renal function. In dogs, nephrectomy is still the most common treatment for pyonephrosis; however, in the present report, a method for percutaneous ultrasound-guided drainage of the renal pelvis in dogs with pyonephrosis that does not require local or general anesthesia was described, and results of the procedure in 2 dogs were reported. Briefly, dogs were positioned in lateral recumbency with the affected side up, and skin overlying the affected kidney was aseptically prepared. The dilated renal pelvis was punctured percutaneously, under ultrasound guidance, with a 22-gauge needle, and a sample of material was obtained for analysis. The needle was then replaced with an IV catheter, and as much pus as possible was removed from the renal collecting system. A povidone iodine solution was then used to lavage the renal pelvis. Ultrasound-guided drainage and lavage of the renal pelvis was repeated daily until the renal pelvis was so small that it could no longer be punctured. Both dogs recovered and were reported by the owners to be healthy after the procedure.  相似文献   
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56.
Praziquantel (PZQ) is a broadly effective trematocide and cestocide, widely employed in veterinary and human medicine. In view of several differences in both its pharmacokinetic profile in different animal species and in the cytochrome P450-dependent system between ruminant and nonruminant species, the present study was undertaken to determine the pharmacokinetics of this drug, its effects on the P450 system and the involvement of cytochrome P450 in its metabolism in 3-month-old lambs infested by Fasciola hepatica. Following both oral and i.m. administration, PZQ disposition was best described by a linear one-compartment open model with a rapid absorption and elimination. Although the PZQ dose used by the i.m. route was only half of that used by the oral route, the mean PZQ plasma concentration was higher after i.m. than after oral treatment. Oral treatment with 30 mg/kg/day of PZQ did not modify the mono-oxygenase activities tested, whilst the administration of PZQ at a dose of 60 mg/kg/day for 2 days caused a significant decrease in the P450 3A-dependent erythromycin N-demethylase and 6beta testosterone hydroxylase activities. From the incubation of microsomes from lambs not treated with PZQ, a single metabolite (PZQ 11b-OH or PZQ 1-OH) was identified by GC/MS analysis. By selective inhibition of the 3A subfamily performed with triacetyloleandromycin, the production of this metabolite declined by about 90% suggesting a prominent role of P450 3A isoforms in this oxidation. These features indicate that agents or drugs which are able to modulate P450 3A-dependent catalysis may interfere with the metabolism, bioavailability and therapeutic effects of PZQ.  相似文献   
57.
Findings of hepatic and gallbladder ultrasonography were analyzed in 12 dogs with gallbladder and/or extrahepatic biliary tract obstruction and compared with the results of exploratory laparotomy. Hepatic ultrasonography demonstrated normal liver in 2 dogs and hepatic abnormalities in 10 animals. The following ultrasonographic diagnoses were established compared to surgical findings: gallbladder obstruction caused by bile sludge (correct/incorrect: 1/2, surgical diagnosis: choleliths in one case), gallbladder obstruction caused by neoplasm (0/1, surgical diagnosis: mucocele), gallbladder and extrahepatic biliary tract obstruction due to choleliths (3/3), extrahepatic biliary tract obstruction caused by pancreatic mass (1/1) and small intestinal volvulus (1/1). Bile peritonitis caused by gallbladder rupture (4/4) was correctly diagnosed by ultrasound, aided with ultrasonographically-guided abdominocentesis and peritoneal fluid analysis. Rupture of the gallbladder should be suspected in the presence of a small, echogenic gallbladder or in the absence of the organ together with free abdominal fluid during ultrasonography. Laparotomy was correctly indicated by ultrasonography in all cases. However, the direct cause of obstruction could not be determined in 2 of the 12 dogs by ultrasonography alone.  相似文献   
58.
The 'Muguga cocktail' which is composed of three Theileria parva stocks Muguga, Kiambu 5 and Serengeti-transformed has been used extensively for live vaccination against East Coast fever in cattle in eastern, central and southern Africa. Herein we describe the molecular characterisation of the T. parva vaccine stocks using three techniques, an indirect fluorescent antibody test with a panel of anti-schizont monoclonal antibodies (MAb), Southern blotting with four T. parva repetitive DNA probes and polymerase chain reaction (PCR)-based assays detecting polymorphism within four single copy loci encoding antigen genes. The Muguga and Serengeti-transformed stocks exhibited no obvious differences in their reactivity with the panel of MAbs, whereas Kiambu 5 differed with several MAbs. Kiambu 5 DNA was very distinct from the Muguga and Serengeti-transformed isolates in the hybridisation pattern with all four nucleic acid probes, whereas Muguga and Serengeti-transformed isolates exhibited minor differences and could not be discriminated with one of the probes. PCR amplification in combination with restriction fragment length polymorphism analysis indicated that Kiambu 5 was also markedly divergent from the Muguga and Serengeti-transformed stocks within two of the four antigen coding genes. The T. parva Serengeti-transformed stock did not contain a 130 base pair insert within the p67 sporozoite antigen gene, which has been observed previously in most T. parva parasites isolated from buffalo, and could not be discriminated from T. parva Muguga at any of the four single copy loci. Collectively the data indicate that two of the cocktail components T. parva Serengeti-transformed and Muguga are genetically closely related, while the third component Kiambu 5 is quite distinct. Based on the findings, there may be a need to include only one of the T. parva Muguga and Serengeti-transformed components in the immunising cocktail. The study demonstrates the value of molecular characterisation data for monitoring of live vaccines.  相似文献   
59.
The phenotypic characteristics are described for the activity of polymorphonuclear leucocytes NMN) obtained by either lavage of the cavity system of juvenile mammary glands stimulated with a synthetic muramyl dipeptide analogue or isolation from the peripheral blood. Attention was paid to the variability of characteristics and its sources, and to correlations among them. The following characteristics were investigated in 27 clinically healthy, unbred Bohemian Red Pied x Holstein heifers: migration activity in situ, number of phagocytosing PMN, phagocytotic index, bactericidal activity of PMN and unstimulated and zymosan-stimulated luminol-dependent chemiluminescence. Considerable individual variation was found in the characteristics. Significant differences between blood PMN and PMN from lavages after influx induction were found for bactericidal activity (P < 0.05) and chemiluminescence (P < 0.01). A significant correlation between blood PMN and mammary gland PMN was found only for the number of phagocytosing cells (r = 0.329; P < 0.01). Highly significant positive correlations (P < 0.01) were demonstrated between the number of phagocytosing PMN [a], phagocytotic index [b], and bactericidal activity [c] in both blood PMN (r(ab) = 0.602; r(ac) = 0.565; r(bc) = 0.529) and mammary gland PMN (r(ab) = 0.730, r(ac) = 0.618, r(bc) = 0.589). No significant correlation was demonstrated for non-stimulated (NS), zymosan-stimulated (ZS), or opsonized zymosan-stimulated (OZS) chemiluminescence with any of the other characteristics of phagocytotic activity, in either blood PMN or mammary gland PMN (P > 0.05). The animal was a highly significant source of variability for all the phagocytotic activity characteristics (P < 0.01). Udder quarter was a non-significant source of variability for all the characteristics of phagocytotic activity except for NS chemiluminescence (P < 0.05) and ZS or OZS chemiluminescence (P < 0.01). However, udder quarter was a non-significant source of variability of chemiluminescence indices ZS/NS and OZS/NS (P > 0.05). It has been demonstrated that in situ migration activity, the number of phagocytosing PMN, phagocytotic index, bactericidal activity of PMN and chemiluminescence indices of PMN collected from juvenile mammary glands of unbred heifers after influx induction can be regarded as candidate early markers of resistance to mammary infections.  相似文献   
60.
Confocal scanning laser ophthalmoscopy (CSLO) is a new technique that enables ocular fundus image recording and retinal dynamic angiography to be performed. The ocular fundus image is acquired sequentially, point by point, and is reconstructed on a video monitor at the rate of 25 images per second. The feasibility of performing both ocular fundus image recordings and retinal angiography image recordings were tested on two dogs, two monkeys and two minipigs using a 40° field I + Tech CSLO. Fundus area of each dog, monkey and minipig were examined without any additional optical devices. The ocular fundus and angiography images were recorded, stabilized and analyzed under the same conditions. For each species, all images were easily recorded without any additional optical device in a lighted room and the morphology of the retinal images generated was similar to those obtained with a camera or angiography of higher resolution. Capillary phase or venous times are presented. Image recording at 25 frames/second enabled more retinal dynamics to be demonstrated than with use of regular angiography. This technique is noninvasive and easy to perform if the eye is fixed and eyelids maintained open. It also allows exploration of retinal microvascularization and could be utilized for clinical, pharmacologic and toxicologic investigations as well.  相似文献   
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