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51.
Perosomus elumbis is an occasionally found congenital anomaly of unknown etiology and is characterized by partial or complete agenesis of lumbar, sacral and coccygeal vertebrae and ankylosis of the hindlimbs. A 2-day-old female Holstein calf presented nearly normal forelimbs but flexure and ankylosis of the hindlimbs. The vertebrae and pelvic malformations and agenesis were radiographed and then necropsied. Mild ankylosis of the hindlimbs, absence of cauda equina, left scoliosis in state of fusion of T11 and T12 and complete fusion of L4 and L5, narrowed pelvic canal and misshapen ilium were confirmed. However, abnormal development or agenesis was not observed in the urogenital and intestinal system in this calf.  相似文献   
52.
The effect of low dose dopamine on the excretory urographic image quality and contrast media-induced nephropathy in normal dogs (experiment 1) and the dogs with decreased renal function (experiment 2) were assessed. In experiment 2, decreased renal function was induced by gentamicin overdose. In each experiment, animals were divided into 3 groups. In group 1, only contrast medium (iohexol) was administered. In group 2, contrast medium plus intravenous fluid (0.9% saline) were administered. And in group 3, contrast medium plus intravenous fluid and low dose dopamine were administered. Investigated parameters included intrarenal resistive index (RI), serum BUN and creatinine concentrations, contrast medium elimination time and radiographic image quality. In experiment 1, RI of group I increased at 80 min after contrast medium administration (p<0.05), but RI of group 3 decreased at 48 and 72 hr (p<0.05). Serum BUN concentration of group 1 was higher than that of group 2 and 3 (p<0.05); in radiographic examination, contrast medium elimination time decreased in group 2 and 3, but image quality of group 2 was inferior to that of group 3. In experiment 2, image quality of group 3 only provided adequate visualization of renal structures. The formula of contrast medium plus low dose dopamine was found to provide good nephrogram and pyelogram image quality without supplemental contrast medium, and to protect renal tubules from prolonged exposure to concentrated contrast medium.  相似文献   
53.
54.
Journal of Soils and Sediments - Carbon capture and storage (CCS) has been frequently discussed as a strategy for meeting CO2 emission reduction and its targets. However, some critical issues have...  相似文献   
55.
To investigate the hepatic metabolism of the new insecticide flupyrazofos [O,O-diethyl O-(1-phenyl-3-trifluoromethylpyrazol-5-yl) phosphorothioate], isolated rat liver was perfused with flupyrazofos under single-pass conditions. In outflow perfusate and bile, 1-phenyl-3-trifluoromethyl-5-hydroxyprazole (PTMHP), PTMHP-sulfate and PTMHP-glucuronide conjugates were identified as the metabolites of flupyrazofos. However, O,O-diethyl O-(1-phenyl-3-trifluoromethylpyrazol-5-yl) phosphate (flupyrazofos oxon) was not detected. A HPLC method with UV detection was used to investigate the hepatic disposition of flupyrazofos and its metabolite PTMHP. The concentrations of flupyrazofos, PTMHP and PTMHP conjugates in outflow perfusate reached steady-state levels within 20 min after commencing perfusion of 7.3 microM flupyrazofos. At steady state, the mean extraction ratio of flupyrazofos was 0.93 (+/- 0.01) and clearance was 26.1 (+/- 0.2) ml min-1 which nearly approached perfusate flow rate (28 ml min-1). PTMHP accounted for 55.7 (+/- 5.8)% of eliminated flupyrazofos and was recovered as unchanged PTMHP, PTMHP-sulfate and PTMHP-glucuronide in the bile as well as the outflow perfusate.  相似文献   
56.
Juvenile sporophytes and gametophytes of Ecklonia stolonifera were incubated in combinations of three pCO2 levels (360, 720 and 980 ppmv) and two temperatures (10 and 15°C for sporophytes; 15 and 20°C for gametophytes) to examine potential effects of climate change on photosynthesis and growth. Sporophytes had significantly higher maximum quantum yields (Fv/Fm) and maximum relative electron transport rates (rETRmax) at 720 ppmv than 360 and 980 ppmv. Also, these parameters were significantly lower at higher temperature of 15°C than at 10°C. Growth of female gametophytes was maximal at 360 ppmv rather than enriched pCO2 levels. Female gametophytes had significantly lower growth at higher temperature of 20°C than at 15°C. These results indicate effects of elevated pCO2 varied between generations: stimulating sporophytic photosynthesis and inhibiting gametophytic growth. Ocean acidification and warming would constitute a grave threat to seedling cultivation of E. stolonifera caused by growth inhibition of gametophytes at high pCO2 levels and temperatures.  相似文献   
57.
The H3N2 subtype of influenza A viruses isolated from pigs in the United States and Canada has shown both genetic and antigenic diversity. The objective of this study was to determine the serologic and genetic characteristics of contemporary strains of these viruses. Genetic analysis of 18 reference strains and 8 selected strains demonstrated differences in 1% to 9% of the nucleotides of the hemagglutinin (HA) gene. Phylogenetic analysis of the HA gene revealed 3 genetic clusters, as well as divergence of cluster III viruses from a cluster III prototype virus (A/Swine/Illinois/21587/99). By means of 1-way cross-hemagglutination inhibition with antiserum against 5 field isolates and 3 vaccine viruses, most of 97 isolates tested could be placed in 1 of 3 serogroups. The several isolates that did not react with any antiserum were in genetic cluster III, which suggests that continuous antigenic drift in cluster III may have resulted in virus variants. The efficacy of commercial vaccines against these virus variants should be evaluated with vaccination and challenge studies.  相似文献   
58.
To investigate the effects of lysine restriction and subsequent realimentation on growth performance, blood profiles and gene expression of leptin and myostatin, 128 weaned pigs [initial body weight (BW) 6.96 ± 1.07 kg, 26 ± 2 days of age] were randomly allotted to four treatments. The starter diets during the first 2 weeks (P1) contained 100%, 80%, 70% or 60% of recommended lysine levels ( National Research Council, 1998 ). Then, common grower 1 and 2 diets were offered for 2 weeks (P2 and P3) each. During P1, average daily gain (ADG) was linearly reduced (p < 0.05) with the increasing levels of lysine restriction. Growth rate was greater in pigs previously fed lysine‐restricted diets than well‐fed pigs although it did not reach a significant level during realimentation. However, the final BW and overall ADG were the lowest (p < 0.05) and F/G was poor in pigs fed 60% lysine diet. Relative visceral organ weights and composition of skeletal muscle were similar (p > 0.05) among the treatment. Blood triglyceride and glucose levels were increased (p < 0.05) during P1, while blood urine nitrogen, total protein and albumin levels were decreased (p < 0.05) during P2 with the reduction in dietary lysine levels. The abundance of myostatin mRNA in skeletal muscle and leptin mRNA in subcutaneous adipose tissue were lower (p < 0.05) in lysine‐restricted pigs than in pigs fed non‐restricted diets. In conclusion, 80% and 70% lysine restriction of starter diets resulted in inferior growth and compensatory growth effect was noted during realimentation, while 60% lysine restriction had a negative influence on growth performance. Moreover, the changes in myostatin and leptin mRNA abundance caused by nutritional manipulations may be involved in the regulation of protein and fat deposition in young pigs.  相似文献   
59.
In order to examine an association between porcine circovirus type-2 (PCV2) infection and reproductive failure in pigs, sera (n = 171) from stillborn fetuses were collected from 3 different farms with prolonged histories of reproductive problems. These sera were tested for the presence of antibodies to PCV2 using an immunoperoxidase monolayer assay. Of the 171 sera tested, 28 had PCV2 antibody titers of ≥ 1:16. When these 28 samples were tested by a polymerase chain reaction assay, 13 were found to contain PCV2 viral DNA. Of these 13 samples containing both PCV2 antibodies and viral DNA, 9 yielded PCV2 on virus isolation. Amino acid sequences comprising open reading frame 2 of PCV2 from 2 of these isolates were compared to PCV2 isolates from cases of post-weaning multi-systemic wasting syndrome (PMWS). The amino acid sequences of the 2 isolates from stillborn pigs were shown to be nearly identical to each other, as well as to other PCV2 isolates associated with reproductive failure. When compared with PMWS isolates, the isolates from the stillborn fetuses showed differences of at least 2 amino acids. These results confirm previous findings that transplacental infection of PCV2 occurs in the field and that stillbirths in pigs may be associated with PCV2 infections. At present, the significance of minor differences in amino acid sequences is not known.  相似文献   
60.
A durable aroma finishing for PET fabric was carried out by adopting poly(vinyl acetate) (PVAc) nanoparticles containing lavender oil (LO) in core. Relatively small size of PVAc nanoparticles (ca. 244 nm of mean particle diameter) was expected to resist the frictional destruction of the particles, which is frequently observed in cases of microcapsules. PVAc nanoparticles containing LO in core were prepared by emulsification-diffusion method and their application as an aroma releasing agent for PET fabrics was assessed through the observation of releasing profiles of LO in ethanol for experimental acceleration. Melamine-formaldehyde (MF) microcapsules containing LO were also prepared and treated on fabrics for comparison. PVAc nanoparticles treated on PET fabric showed higher initial releasing amount, which was ascribed to the enhanced surface area. After 2 days of releasing, PET fabric treated with PVAc nanoparticles showed slower and more stable releasing profile and reached about 12 ppm of cumulative release after 16 days, which was under two thirds of that with MF microcapsules. PVAc nanoparticles can be used as an agent for durable aroma finishing of PET fabrics.  相似文献   
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