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11.
SUMMARY: Linear regression analysis was used to describe the decline in numbers of Culicoides brevitarsis Kieffer into winter with monthly maximum, average and minimum temperatures at the southern limits to its distribution in New South Wales. From this, low temperature thresholds were derived when C brevitarsis would be absent from the field. The low minimum threshold ± 2 SE (95% Confidence Interval) of 8.1 ± 0.3°C was used with historical temperature data to estimate the last month that the species should occur (March to June) and the mean number of months (2 to 6.5) below the threshold at 17 selected sites. Probability for survival during winter at these sites was estimated from years when the number of consecutive months below the threshold was ≤ 2 months. This varied from zero to 51% depending on the location of the site. Last occurrence was 0.7 months later on average and absolute probabilities for survival ranged from zero to 100% when the temperatures were increased by an arbitrary 2°C.  相似文献   
12.
秦律的赀罚与二年律令的罚金虽然名称完全不同,但两者具有继承关系。秦律的赀二甲是对盗窃额未满110钱-22钱的处罚,赀一盾是对未满22钱-1钱的处罚。秦律的这些内容由二年律令继承。赀罚原来分为赀一盾、赀二盾、赀一甲、赀二甲等四个等级,后来赀二盾逐渐消失,形成赀一盾、赀一甲、赀二甲三个等级,这三个等级的比例为1:2:4,与二年律令的罚金一两、二两、四两的比例关系相一致。赀一盾的罚额为672钱,与罚金一两的价额625钱相差不大。赀一盾的价额672钱与秦律规定的日均劳动价额8钱有关,以一日劳役为八钱计算,672钱  相似文献   
13.
Improving our understanding of the mechanisms controlling the corpus luteum (CL) and its role in regulating the reproductive cycle should lead to improvements in the sustainability of today's global animal industry. The corpus luteum (CL) is a transient endocrine organ composed of a heterogeneous mixture steroidogenic, endothelial and immune cells, and it is becoming clear that immune mechanisms play a key role in CL regulation especially in luteolysis. Toll‐like receptors (TLR) mediate innate immune mechanisms via the production of pro‐inflammatory cytokines, especially within various tissues, although the role of TLR within CL remains unknown. Thus, the objectives of this study were to characterize TLR mRNA expression in the CL during the oestrous cycle and in pregnancy (day 30–50), and to examine the role of TLR signalling in luteal cells. Corpora lutea were collected at various stages of the cycle and pregnancy and analysed for TLR and cytokine mRNA expression. In addition, luteal cells were cultured with the TLR4 ligand (lipopolysaccharide, LPS) for 24 h to evaluate the role of TLR4 in regulating luteal function. Toll‐like receptors 1, 2, 4, 6, tumour necrosis factor alpha (TNF), interferon gamma (IFN‐G), and interleukin (IL)‐12, mRNA expressions were greatest in regressing CL compared with earlier stages (p < .05), whereas no change was observed for IL‐6 mRNA expression. Cytokine mRNA expression in cultured luteal cells was not altered by LPS. Based on these data, one or more of the TLRs found within the CL may play a role in luteolysis, perhaps via pro‐inflammatory cytokine mRNA expression.  相似文献   
14.
A previously unknown solid phase of H2O has been identified by its peculiar growth patterns, distinct pressure-temperature melting relations, and vibrational Raman spectra. Morphologies of ice crystals and their pressure-temperature melting relations were directly observed in a hydrothermal diamond-anvil cell for H2O bulk densities between 1203 and 1257 kilograms per cubic meter at temperatures between -10 degrees and 50 degreesC. Under these conditions, four different ice forms were observed to melt: two stable phases, ice V and ice VI, and two metastable phases, ice IV and the new ice phase. The Raman spectra and crystal morphology are consistent with a disordered anisotropic structure with some similarities to ice VI.  相似文献   
15.
16.
This work focused on the effect of maca on lipid, anti-oxidative, and glucose parameters in hereditary hypertriglyceridemic (HHTg) rat. Maca (1%) was administred to rats as a part of a high-sucrose diet (HSD) for 2 weeks. Rosiglitazone (0.02%) was used as a positive control. Maca significantly decreased the levels of VLDL (very low density lipoproteins), LDL (low density lipoproteins), and total cholesterol, and also the level of TAG (triacylglycerols) in the plasma, VLDL, and liver. Maca, as well as rosiglitazone, significantly improved glucose tolerance, as the decrease of AUC (area under the curve) of glucose showed, and lowered levels of glucose in blood. The activity of SOD (superoxide dismutase) in the liver, the GPX (glutathione peroxidase) in the blood, and the level of GSH (glutathione) in liver increased in all cases significantly. Results demonstrate that maca seems to be promising for a positive influence on chronic human diseases (characterized by atherogenous lipoprotein profile, aggravated antioxidative status, and impaired glucose tolerance), and their prevention.  相似文献   
17.
Transgenic research on cattle embryos has been developed to date using viral or plasmid DNA delivery systems. In this study, a different gene delivery system, piggybac transposition, was employed to investigate if it can be applied for producing transgenic cattle embryos. Green or red fluorescent proteins (GFP or RFP) were transfected into donor fibroblasts, and then transfected donor cells were reprogrammed in enucleated oocytes through SCNT and developed into pre-implantation stage embryos. GFP was expressed in donor cells and in cloned embryos without any mosaicism. Induction of RFP expression was regulated by doxycycline treatment in donor fibroblasts and pre-implantational stage embryos. In conclusion, this study demonstrated that piggybac transposition could be a mean to deliver genes into bovine somatic cells or embryos for transgenic research.  相似文献   
18.
Some effects of dietary medicinal herbs mixture (HM), Massa medicata fermentata, Crataegi fructus, Artemisia capillaries, and Cnidium officinale, in the proportions 2∶2∶1∶1 were identified in juvenile Japanese flounder Paralichthys olivaceus. In an 8-week feeding trial, fish were fed with 0.1, 0.3, 0.5, and 1.0% HM in a moist diet composed of horse mackerel and an artificial diet in equal parts. Fish fed the diets with 0.3, 0.5, and 1.0% HM showed higher weight gain and feed efficiency than fish in 0.1 and 0% HM feed groups. No significant differences were found in survival, feed intake, final carcass proximate composition, hemoglobin and hematocrit levels, plasma total cholesterol level, and alanine aminotransferase activity among the dietary treatments. Fish fed with 0.3, 0.5, and 1.0% HM showed higher total carcass unsaturated fatty acid content and docosahexaenoic acid (22∶6n−3) level, and plasma high density lipoprotein-cholesterol level, but lower carcass saturated fatty acid content and plasma aspartate aminotrasferase activities than the control group. Moreover, a 10-min air exposure test with five times repeat, and an anesthesia test for 2 min with 200 p.p.m. 2-phenoxyethanol, also revealed lower mortality and lower recovery time in 0.3, 0.5, and 1.0% HM groups than the control group at the end of the trial. These results indicate that the medicinal herb mixture is useful to improve growth, fatty acid utilization, and stress recovery in the Japanese flounder.  相似文献   
19.
AIM: To determine the effect of grazing pasture that had a low selenium (Se) concentration on serum concentrations of tri iodothyronine (T3) and thyroxine (T4), and erythrocyte glutathione peroxidase (GSH-Px) activity in dairy cows.

METHODS: Forty pregnant Friesian cows were grazed on pasture that contained 0.03–0.04 ppm Se on a dry matter (DM) basis. Two months before parturition, 20 cows were randomly selected and treated with 1 mg Se/kg bodyweight subcutaneously, as barium selenate (Group Se-S). The other group (Se-D) was not supplemented. Blood samples were taken before supplementation (-60 days) and 30, 60, 90, 180 and 270 days after parturition, for determination of concentrations of T3 and T4 in serum, and GSH-Px activity in erythrocytes.

RESULTS: Erythrocyte GSH-Px activity in the Se-D group was >60 U/g haemoglobin (Hb) throughout the experiment. Supplementation increased (p>0.05) activities to >130 U/g Hb throughout lactation. Mean serum concentrations of T4 in Se-D and Se-S cows increased from 23.7 (SEM 0.7) and 23.4 (SEM 0.8) nmol/L, respectively, in the prepartum period to 69.6 (SEM 0.1) and 67.6 (SEM 0.2) nmol/L, respectively, at 180 days of lactation (p>0.01), and no effect of Se supplementation was evident. Serum concentrations of T3 in Se-D cows decreased (p>0.05) from 1.6 (SEM 0.1) nmol/L prepartum to 1.0 (SEM 0.2) nmol/L at the beginning of lactation, and remained lower (p>0.05) than those in the Se-S cows which did not decrease after calving and ranged from 1.9 (SEM 0.1) to 2.4 (SEM 0.2) nmol/L throughout lactation.

CONCLUSIONS: Serum T3 concentrations decreased during early lactation in unsupplemented cows grazing pastures low in Se (0.03–0.04 ppm) and both serum T3 and erythrocyte GSH-Px activities were consistently lower throughout lactation compared with Se-supplemented cows. Se supplementation had no effect on serum T4 concentrations.  相似文献   
20.
In cats, accuracy of parturition day prediction by ultrasonographic measurement of foetal structures is decreasing towards the end of gestation. Foetal measurements during the last days of pregnancy are scarce. We determined foetal biparietal, abdominal and eye diameter (BPD, AD and ED, respectively) by ultrasonography as well as maternal blood progesterone (P4) within five days of delivery to predict parturition date and calculate accuracy of prediction. Foetal BPD at birth was compared with newborn kitten head diameter (HD). Kitten HD, crown‐rump length (CRL) and body weight were compared by breed and gender. Ultrasonography measurements were carried out on the day of parturition in 14 queens, and on days 62–63 after the first mating and repeated 24–72 hr later in ten other cats. Accuracy of parturition day prediction using BPD and AD was determined based on the equations of Beccaglia et al. (2008) Veterinary Research Communications, 32(Suppl 1), S99 and Garcia Mitacek et al. (2015) Theriogenology, 84, 1131. Progesterone was measured at the time of presentation and repeated 24–72 hr later if parturition did not occur. Data were analysed with linear regression, t test, Mann–Whitney U test, one‐way anova and Kruskal–Wallis test. There was a moderate relationship between BPD, days before birth (DBB) and litter size. AD and DBB had a low agreement, and ED was not associated with DBB. BPD at birth was significantly related to HD. The accuracy of parturition day prediction using BPD and AD was 27–53% and 17–35%, respectively. Kitten HD was associated with body weight, and both were inversely related to litter size. Newborn biometric measurements differed by breed but not by gender. Progesterone decreased towards parturition and reached 3.18 ± 1.68 ng/ml on the day of delivery. In conclusion, close to birth, the combination of foetal ultrasonography and maternal blood P4 rather than each as a sole predictor of parturition is recommended.  相似文献   
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