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A 10‐year‐old entire female Beagle dog was evaluated for an acute history of lethargy, anorexia, and diarrhea. Mammary tumors were detected during physical examination. Ultrasonographic scanning revealed the presence of a unique pattern of multiple, well‐defined and well‐marginated hypoechoic nodules in the muscularis layer of the jejunum. These nodules were not associated with changes in the rest of the normal intestinal layering and were not causing signs of intestinal obstruction. Mammary carcinoma metastases to the intestinal muscularis layer were diagnosed based on histopathological examination.  相似文献   
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Summary Sunflower lines breeding true for very high oleic acid content in their oil (average levels higher than 85%) were crossed with standard sunflower lines with mean oleic acid levels of 30%. Analysis of the oil of F1 seeds indicated dominance for high oleic levels and control of the genotype of the embryo. Segregating generations were obtained selfing heterozygous high oleic BCnF1 plants from several generations of a backcrossing program to incorporate the high oleic character to standard inbred lines and testcrossing these plants to low oleic material. Analysis of F2 and testcrossed seeds showed three kind of segregations, in both F2 and testcrossed populations, with different proportions of low, intermediate and high oleic types. Genetic analysis of these data supported the hypothesis, that the high oleic character is controlled by three dominant complementary genes OL1, OL2 and OL3. Additional data showing F1 seeds with intermediate oleic content and segregations for high oleic in progenies of intermediate types, suggest the presence of major factors modifying high oleic acid content.  相似文献   
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Ethiopian mustard (Brassica carinata Braun) is a potential oil crop in which genes for low erucic acid content of the seed oil have not yet been found. In order to solve this problem the potential of rapeseed (B. napus L.) varieties as a source of these genes has been tested. Reciprocal F1 hybrids between B. carinata and a low erucic acid variety of B. napus, F2, and backcrosses with B. carinata were obtained. The fatty acid composition was determined in half seeds of F1 and segregating generations from reciprocal interspecific crosses. The genetic analysis indicated that the erucic acid content of the seed oil of B. carinata is controlled by two genes with no dominance and additive in action.  相似文献   
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OBJECTIVES: To examine if obesity status and socio-economic and lifestyle factors are associated with self-reported past food habit change, and also whether the level of obesity depends on the reason for change. DESIGN: Cross-sectional analysis within the Malmo Diet and Cancer (MDC) study using data from the baseline examination and the extensive socio-economic and lifestyle questionnaire including questions of past food habit change. The risk of having changed food habits in the past was examined using logistic regression. Mean differences in obesity status across categories of reasons for past food habit change were examined using analysis of variance. SETTING: Malm?, the third largest city in Sweden. SUBJECTS: A sub-sample (15 282 women and 9867 men) from the MDC cohort recruited from 1992 to 1996. RESULTS: Individuals with body mass index (BMI) >30 kg m(-2) had an increased risk of having reported past food habit change compared with individuals with BMI <25 kg m(-2) (odds ratio (OR) = 1.63, 95% confidence interval (CI) = 1.48-1.83 for women; OR = 1.53, 95% CI = 1.32-1.76 for men). The highest level of obesity was observed among individuals who had changed their diet due to reasons related to the metabolic syndrome. Changers were more likely to be highly educated and to live alone, be retired, ex-smokers and non-drinkers at baseline. CONCLUSIONS: Because past food habit change is related to obesity and other lifestyle and socio-economic factors, a complex confounding situation may exist that could seriously influence observed relationships between diet and disease. Studies need to collect information on past food habit change and take this information into account in the analysis and when interpreting study outcomes.  相似文献   
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This study investigated whether changes in the vaginal electrical resistance (VER) of vaginal mucus of weaned sows during the first 7 d post-weaning are associated with time of ovulation. Time of ovulation was determined by ovarian ultrasound carried out from 91 to 146 h after weaning and at different seasons. Vaginal electrical resistance was measured at 20, 44, 68, 91, 96, 102, 115, 120, 126, 140, 146, and 164 h post-weaning and was found to decrease between 120 h and 31 h before ovulation and then increase until 40 to 50 h after ovulation. Duration and timing of the nadir was affected by the season (P < 0.01). Estrus was observed from day 4 after the lowest VER values. Ovulation occurred between late day 5 and late day 6, while VER values were still increasing. Ovulation was earlier in lower parity sows (P < 0.001). Compared to 0 h (ovulation time), VER was significantly lower from 50 to 5 h before ovulation in autumn and from 40 to 21 h in winter, but such differences were not seen in spring. Lowest VER value was not correlated with time of ovulation. It was concluded that VER increases before ovulation and, although this increase is influenced by the season, it cannot be used to accurately predict ovulation in weaned sows.  相似文献   
47.
ObjectiveTo determine the anaesthetic and cardiorespiratory effects of a constant rate infusion of fentanyl in sheep anaesthetized with isoflurane and undergoing orthopaedic surgery.Study designProspective, randomised, ‘blinded’ controlled study.AnimalsTwenty healthy sheep (weight mean 41.1 ± SD 4.5 kg).MethodsSheep were sedated with intravenous (IV) dexmedetomidine (4 μg kg−1) and morphine (0.2 mg kg−1). Anaesthesia was induced with propofol (1 mg kg−1 minute−1 to effect IV) and maintained with isoflurane in oxygen and a continuous rate infusion (CRI) of fentanyl 10 μg kg−1 hour−1 (group F) or saline (group P) for 100 minutes. The anaesthetic induction dose of propofol, isoflurane expiratory fraction (Fe’iso) required for maintenance and cardiorespiratory measurements were recorded and blood gases analyzed at predetermined intervals. The quality of recovery was assessed. Results were compared between groups using t-tests or Mann–Whitney as relevant.ResultsThe propofol induction dose was 4.7 ± 2.4 mg kg−1. Fe’iso was significantly lower (by 22.6%) in group F sheep than group P (p = 0). Cardiac index (mean ± SD mL kg−1 minute−1) was significantly (p = 0.012) lower in group F (90 ± 15) than group P (102 ± 35). Other measured cardiorespiratory parameters did not differ statistically significantly between groups. Recovery times and recovery quality were statistically similar in both groups.Conclusions and clinical relevanceFentanyl reduced isoflurane requirements without clinically affecting the cardiorespiratory stability or post-operative recovery in anaesthetized sheep undergoing orthopaedic surgery.  相似文献   
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The neuronal voltage-gated N-type calcium channel (Cav2.2) is a validated target for the treatment of neuropathic pain. A small library of anthranilamide-derived ω-Conotoxin GVIA mimetics bearing the diphenylmethylpiperazine moiety were prepared and tested using three experimental measures of calcium channel blockade. These consisted of a 125I-ω-conotoxin GVIA displacement assay, a fluorescence-based calcium response assay with SH-SY5Y neuroblastoma cells, and a whole-cell patch clamp electrophysiology assay with HEK293 cells stably expressing human Cav2.2 channels. A subset of compounds were active in all three assays. This is the first time that compounds designed to be mimics of ω-conotoxin GVIA and found to be active in the 125I-ω-conotoxin GVIA displacement assay have also been shown to block functional ion channels in a dose-dependent manner.  相似文献   
50.
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