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51.
The timing of the post-ovulatory progesterone rise is critical to the embryonic development and survival. The aim of this study was to determine the underlying causes of delayed post-ovulatory progesterone rises. Two groups of non-lactating dairy cows with early (n = 11) or late (n = 9) post-ovulatory progesterone rises were created by inducing luteolysis in the presence of either a large (> 10 mm) or small (< 10 mm) follicle, respectively. LH pulses were measured on days 4 (all cows) and 7 (n = 7, early; n = 5, late) (day 1= ovulation). The cows were slaughtered on day 5 (n = 4 each group) or 8 (n = 7, early; n = 5, late). Immunohistochemical analysis for endothelial cells (von Willebrand Factor, VWF), steroidogenic cells (3beta-HSD) and proliferation marker (Ki67) were performed. The basal progesterone production and LH responsiveness (0.001-100 ng/ml) of dispersed luteal cells was investigated. The luteal concentrations of FGF-2 and VEGF were measured by ELISA and RIA, respectively. There were no differences in LH pulse characteristics, area of VWF staining, proliferation index, steroidogenic cell characteristics, basal or LH-stimulated progesterone production by luteal cells between cows with an early or late progesterone rise (P > 0.10). However, the area of VWF staining increased from days 5 to 8, while the proliferation index decreased (P < 0.05). Furthermore, the luteal cells were more responsive to LH on day 8 (P < 0.01). Luteal concentrations of FGF-2 were higher on day 5 (P = 0.05), while VEGF was greater on day 8 (P < 0.01). In conclusion, we have clearly shown that LH support, degree of vascularization or luteal cell steroidogenic capacity were not the major factors responsible for inadequate secretion of progesterone by the developing bovine CL.  相似文献   
52.
Four thoracic evacuation techniques for pneumothorax elimination after diaphragmatic defect closure were compared in 40 canine cadavers. After creating a defect in the left side of the diaphragm, thoracic drainage was performed by thoracostomy tube insertion through the defect and a small (DD-SP) or large (DD-LP) puncture created in the caudal mediastinum, or through both the diaphragmatic defect and intact contralateral diaphragm with a small (DI-SP) or large (DI-LP) puncture in made in the caudal mediastinum. Differences in intrapleural pressure (IPP) between the right and left hemithoraxes after air evacuation along with differences in IPP before making a defect and after air evacuation in each hemithorax were calculated. A difference (p ≤ 0.0011) in IPP between the left and right hemithoraxes after air evacuation as well as before making a defect and after air evacuation in the right hemithorax was detected for the DD-SP group. No significant differences (p ≥ 0.0835) were observed for the DI-LP, DD-LP, or DI-SP groups. Creation of a large mediastinal puncture or thoracic evacuation through both a diaphragmatic defect and intact contralateral diaphragm can facilitate proper pneumothorax elimination bilaterally after diaphragmatic defect closure in dogs with a small puncture in the caudal mediastinum.  相似文献   
53.
AIM: To determine the effect of increasing molybdenum (Mo) intakes on serum and liver copper (Cu) concentrations and growth rates of grazing red deer (Cervus elaphus).

METHODS: Molybdenum- and Cu-amended fertilisers were applied to six 1.1-ha paddocks in a 3 × 2 design. Three levels of Mo were applied on two paddocks at each level in mid April (designated Day 1); levels were: none (control), 0.5 (medium) and 1.0 (high) kg Mo/ha as sodium molybdate. In late May (Day 39), two levels of Cu (none and 3.0 kg Cu/ha, as copper sulphate) were applied to each of the three levels of Mo-treated paddocks. Pasture Mo, Cu and sulphur (S) concentrations were measured at about fortnightly intervals. In late June (Day 74), ten 6-month-old red deer hinds were placed on the six experimental pastures, and serum and liver Cu concentrations were monitored at about monthly intervals for 102 days. The hinds were weighed on four occasions during the trial.

RESULTS: Mean pasture Mo concentrations on Day 56 were 2, 4.6 and 11.3 mg/kg dry matter (DM) for the untreated control, medium and high Mo-treated pastures, respectively. Pasture Cu concentration was 95 mg/kg DM on Day 59, 53 mg/kg DM on Day 90, and 9 mg/kg DM by Day 153. Mean S concentration in pasture was 3.3 (range 3.03–3.45) g/kg DM. Copper application to pasture had no significant effect on serum and liver Cu concentrations in deer so data were pooled within Mo treatment. Mean initial (Day 74) serum Cu concentration was 9.2 µmol/L. In the deer grazing the control Mo pasture, this increased to 10.3 µmol/L on Day 112, before decreasing to 6.4 µmol/L on Day 176. In deer grazing the medium and high Mo-treated pastures, mean serum Cu concentrations were 3.8 and 3.9 µmol/L, respectively, on Day 112, and 2.5 and 3.3 µmol/L, respectively, on Day 176. Mean initial (Day 74) liver Cu concentration was 131 µmol/kg fresh tissue. In the deer grazing the control Mo pasture, this declined to 120 and 52 µmol/kg on Days 112 and Day 176, respectively. In deer grazing the medium and high Motreated pastures, liver Cu concentrations decreased to 55 and 52 µmol/kg fresh tissue, respectively, on Day 112, and 21 and 20 µmol/kg fresh tissue, respectively, on Day 176. Mean serum and liver Cu concentrations were not significantly different between deer grazing the medium and high Mo-treated pastures, and were lower (serum p=0.003, liver p<0.001) in those groups than in deer grazing the untreated control pastures. No clinical signs of Cu deficiency associated with lameness were observed. Deer grazing pastures that had Mo concentrations >10 mg/kg DM had lower (p=0.002) growth rates (100 vs 130 g/day) than those on pastures containing <2.4 mg Mo/kg DM.

CONCLUSION: Increasing pasture Mo concentrations from 2 mg/kg DM to ≥4.6 mg/kg DM significantly reduced serum and liver Cu concentrations in grazing deer. Reduced growth rate was observed at pasture Mo concentrations >10 mg/kg DM.  相似文献   
54.
Fifteen dogs with extrahepatic biliary tract disease underwent cholecystoenterostomy. Long-term survivors were significantly older at presentation (mean age 140.5 months) than dogs that survived the first 20 days after surgery but subsequently died from causes related to the surgery or hepatobiliary disease (mean age 72 months). Dogs that died during the first 20 days had significantly more complications in the hospital than dogs that survived this period. The type of underlying hepatobiliary disease (i.e., benign or malignant) was not associated with either short-term outcome or long-term survival. Eight dogs died from causes related to surgery or hepatobiliary disease. Long-term complications included hepatic abscesses, acquired portosystemic shunts, pancreatitis, and vomiting.  相似文献   
55.
OBJECTIVE: To determine whether lipid particle coalescence develops in veterinary parenteral nutrition (PN) admixture preparations that are kept at room temperature (23 degrees C) for > 48 hours and whether that coalescence is prevented by admixture filtration, refrigeration, or agitation. SAMPLE POPULATION: 15 bags of veterinary PN solutions. PROCEDURES: Bags of a PN admixture preparation containing a lipid emulsion were suspended and maintained under different experimental conditions (3 bags/group) for 96 hours while admixtures were dispensed to simulate IV fluid administration (rate, 16 mL/h). Bags were kept static at 4 degrees C (refrigeration); kept at 23 degrees C (room temperature) and continuously agitated; kept at room temperature and agitated for 5 minutes every 4 hours; kept static at room temperature and filtered during delivery; or kept static at room temperature (control conditions). Admixture samples were collected at 0, 24, 48, 72, and 96 hours and examined via transmission electron microscopy to determine lipid particle diameters. At 96 hours, 2 samples were collected at a location distal to the filter from each bag in that group for bacterial culture. RESULTS: Distribution of lipid particle size in the control preparations and experimentally treated preparations did not differ significantly. A visible oil layer developed in continuously agitated preparations by 72 hours. Bacterial cultures of filtered samples yielded no growth. CONCLUSIONS AND CLINICAL RELEVANCE: Data indicated that the veterinary PN admixtures kept static at 23 degrees C are suitable for use for at least 48 hours. Manipulations of PN admixtures appear unnecessary to prolong lipid particle stability, and continuous agitation may hasten lipid breakdown.  相似文献   
56.
BACKGROUND: Fine needle aspiration (FNA) offers a rapid and minimally invasive means to distinguish malignant from benign neoplasms. However, few studies have been published regarding the cytopathology of mammary tumors in rats despite widespread use of the rat model for breast cancer formation and inhibition. OBJECTIVE: The purpose of this study was to determine the diagnostic accuracy of FNA cytology and to develop distinguishing cytologic criteria for the diagnosis of radiation-induced benign and malignant mammary tumors in rats. METHODS: In a study of radiation-induced mammary carcinogenesis, 100 Sprague-Dawley rats with cutaneous masses were randomly chosen for FNA. The aspirates were smeared, fixed, and stained with a modified Papanicolaou procedure for diagnostic evaluation. Cytologic and histologic diagnoses (benign vs malignant) were compared, and diagnostic accuracy was calculated using the histologic diagnosis as the criterion standard. FNA smears were scored semiquantitatively on a scale of 1-4 for cellularity, atypia, nuclear size, chromatin pattern, nuclear membrane thickness, nucleoli, and mitoses. The background was evaluated for necrosis, hemorrhage, inflammation, and mucosecretory material. Cytomorphologic features were compared statistically between benign and malignant tumors, based on the histologic diagnosis. RESULTS: The sensitivity of FNA was 92.3% and specificity was 89.4% for the detection of malignancy. However, 14% of specimens, all fibroadenomas by histology, had insufficient cells for cytologic evaluation, for an overall accuracy rate of 78.0%. Malignant tumors had significantly higher scores for all cytomorphologic features, and were significantly more likely to contain cell clusters and necrotic debris. CONCLUSIONS: FNA is an accurate method for differentiating benign and malignant rat mammary tumors.  相似文献   
57.
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59.
Cadmium (Cd) accumulation in the aboveground parts of grain crops, and cultivar variation in uptake are of significant concern in the food supply chain. A glasshouse experiment on an acidic yellow sand was conducted to determine the effect of applied cadmium (0, 0.83, 1.67, 2.5, 3.35 mg Cd kg?1 soil) on the grain yield of Lupinus angustifolius L. (narrow-leafed lupin; cv. Gungurru) and Lupinus luteus L. (yellow lupin) cultivars, and the concentration and uptake (content) of cadmium by stems and grain. The addition of Cd decreased the grain yield of all varieties of yellow lupin, except Teo-105. However, the grain yield of narrow-leafed lupin was not significantly (p = 0.05) reduced by the addition of Cd to the soil. The grain yield of yellow lupin varieties of P283553 and 94017-3 decreased by 50–60% by the addition of Cd compared to other varieties (Wodjil, 94DO19-1) where grain yield decreased by about 10% with Cd application. Cadmium concentration in plant stems and grain and the content of Cd in lupin plants increased markedly with increasing levels of Cd in the soil. The increase in Cd concentration in stems and grain with the addition of Cd was always higher in yellow lupin than for narrow-leafed lupin. The Cd concentration in the grain of narrow-leafed lupin was about 40% of that of yellow lupin. The concentration of Cd in the stem at maturity was always higher than the Cd concentration in the grain for both Lupinus species. Yellow lupin, except 94DO19-1 had higher concentration of Cd in grain where no Cd was applied to the soil. However, compared to narrow-leafed lupin, all yellow lupin varieties had higher concentration of Cd in grain where Cd was applied to the soil.  相似文献   
60.
Femtosecond laser pulses and coherent two-phonon Raman scattering were used to excite KTaO3 into a squeezed state, nearly periodic in time, in which the variance of the atomic displacements dips below the standard quantum limit for half of a cycle. This nonclassical state involves a continuum of transverse acoustic modes that leads to oscillations in the refractive index associated with the frequency of a van Hove singularity in the phonon density of states.  相似文献   
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