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排序方式: 共有228条查询结果,搜索用时 15 毫秒
41.
CRS Mattoso RK Takahira SL Beier JP Araujo Jr JE Corrente 《Reproduction in domestic animals》2013,48(3):416-422
Plasmatic concentrations of von Willebrand Factor (vWF) increase during pregnancy in humans and dogs; however the mechanism of such increase is still not well defined. The aims of this study were: (i) to evaluate changes in vWF concentration during pregnancy and during the subsequent oestrous cycle in bitches affected and unaffected by von Willebrand Disease (vWD); (ii) to correlate the vWF levels and cortisol levels in both groups. Seven vWD affected (GI) and nine unaffected (GII) bitches were used. The animals were assessed during pregnancy, parturition, lactation and non‐gestational oestrous cycle in 11 moments (Pregnancy 1, Pregnancy 2, Parturition, Lactation 1, Lactation 2, Lactation 3, Anestrus, Proestrus, Oestrus, Diestrus 1, and Diestrus 2). The following tests were performed; measurement of von Willebrand factor antigen (vWF:Ag), albumin and cortisol. In both groups, vWF concentration remained stable during the non‐gestational oestrous cycle, but increased during pregnancy, with the highest value observed at parturition. Increases of 70% and 124% in vWF were seen in GI and GII, respectively, compared to anestrus. No correlation was found between vWF and cortisol. Values of vWF:Ag changed during pregnancy, with a peak at parturition, both in vWD affected and unaffected animals. Values of vWF were not altered in the different phases of the oestrous cycle following pregnancy in both groups. Evaluation of vWF during pregnancy can cause false negative results for vWD, but assessment can be performed at any point in the oestrous cycle of non‐pregnant bitches. 相似文献
42.
Prolonged summer droughts due to climate change are expected for this century, but little is known about the effects of drying and wetting on biogenic trace‐gas fluxes of forest soils. Here, the response of CO2, N2O, NO, and CH4 fluxes from temperate forest soils towards drying–wetting events has been investigated, using undisturbed soil columns from a Norway spruce forest in the “Fichtelgebirge”, Germany. Two different types of soil columns have been used for this study to quantify the contribution of organic and mineral horizons to the total fluxes: (1) organic horizons (O) and (2) organic and mineral soil horizons (O+M). Three drying–wetting treatments with different rewetting intensities (8, 20, and 50 mm of irrigation d–1) have been compared to a constantly moist control to estimate the influence of rainfall intensity under identical drying conditions and constant temperature (+15°C). Drought significantly reduced CO2, N2O, and NO fluxes in most cycles. Following rewetting, CO2 fluxes quickly recovered back to control level in the O columns but remained significantly reduced in the O+M columns with total CO2 fluxes from the drying–wetting treatment ranging approx. 80% of control fluxes. Fluxes of N2O and NO remained significantly reduced in both O and O+M columns even after rewetting, with cumulative fluxes from drying–wetting treatments ranging between 20% and 90% of the control fluxes, depending on gas and cycle. Fluxes of CH4 were small in all treatments and seem to play no significant role in this soil. No evidence for the release of additional gas fluxes due to drying–wetting was found. The intensity of rewetting had no significant effect on the CO2, N2O, NO, and CH4 fluxes, suggesting that the length of the drought period is more important for the emission of these gases. We can therefore not confirm earlier findings that fluxes of CO2, N2O, and NO during wetting of dry soil exceed the fluxes of constantly moist soil. 相似文献
43.
Daphne W. Goldberg Miriam R. Fernandes Fbio P. Sellera Daniela G. C. Costa Ana Paula Loureiro Bracarense Nilton Lincopan 《Zoonoses and public health》2019,66(5):540-545
CTX‐M‐type extended‐spectrum β‐lactamase (ESBL)‐producing Enterobacteriaceae have become identified in marine ecosystem constituting a serious ecological issue. In this respect, although contamination of coastal waters and seafood, and even colonization of seabirds and fishes have been increasingly reported, molecular data are lacking to elucidate the clinical impact of ESBL producers in infected marine animals. In this study, using a genomic approach, we have analysed the genetic background of CTX‐M‐15‐producing Enterobacter hormaechei (belonging to the international human clone ST114) and Citrobacter freundii (ST265) co‐infecting a free‐living green turtle (Chelonia mydas) suffering from septic arthritis, which progressed to generalized coelomitis and death. Wide resistome of these pathogens contributed to treatment failure and death of the animal. 相似文献
44.
Pregnancy Loss in Dairy Cattle: Relationship of Ultrasound,Blood Pregnancy‐Specific Protein B,Progesterone and Production Variables
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G Gábor JP Kastelic Z Abonyi‐Tóth P Gábor T Endrődi OG Balogh 《Reproduction in domestic animals》2016,51(4):467-473
Objectives were to determine associations between percentage pregnancy loss (PPL) in dairy cattle and: (i) pregnancy diagnosis by ultrasonography; (ii) pregnancy diagnosis by serum pregnancy‐specific protein B (PSPB) concentrations, with or without serum progesterone concentrations; and (iii) production and environmental factors. This study included 149 822 pregnancy diagnoses conducted over 13 years in Holstein‐Friesian cows in Hungarian dairy herds. The following were determined: PPL in cows diagnosed pregnant by transrectal ultrasonography 29–42 days after artificial insemination (AI; n = 11 457); PPL in cows diagnosed pregnant by serum PSPB 29–35 days after AI (n = 138 365); and PPL and its association with serum progesterone concentrations, PSPB and production/environmental variables. The definition of PPL was percentage of cows initially diagnosed pregnant based on ultrasonography or PSPB, but not pregnant when examined by transrectal palpation 60 –70 days after AI. The PPL was lower (p < 0.001) in cows following ultrasonographic vs PSPB diagnosis of pregnancy at 29–35 days (8.1 vs 19.3%, respectively), but was higher in cows following ultrasonographic pregnancy diagnosis on 29–35 vs 36–42 days (8.1 vs 7.1%, respectively, P < 0.05). Furthermore, 72.9% of pregnancies with ultrasound‐detected morphological abnormalities resulted in pregnancy loss. As a subset of PSPB data, a fully quantitative PSPB assay was used for 20 430 samples; PPL in cows with a high PSPB concentration (>1.1 ng/ml) was lowest (15.0%), whereas cows with low concentrations of both PSPB and progesterone (0.6–1.1 and <2 ng/ml, respectively) had the highest PPL (76.3%; p < 0.0001). Furthermore, PPL was higher in cows with advanced parity and with high milk production, when ambient temperatures were high, although body condition score (BCS) had no effect on PPL. Finally, there were no significant associations between serum PSPB and environmental temperatures or number of post‐partum uterine treatments. 相似文献
45.
Zhoukoudian is widely regarded as having the oldest reliable evidence for the controlled use of fire by humans. A reexamination of the evidence in Layer 10, the earliest archaeological horizon in the site, shows that burned and unburned bones are present in the same layer with stone tools. However, no ash or charcoal remnants could be detected. Hence, although indirect evidence for burning is present, there is no direct evidence for in situ burning. 相似文献
46.
JE Lupton ET Baker N Garfield GJ Massoth RA Feely JP Cowen RR Greene TA Rago 《Science (New York, N.Y.)》1998,280(5366):1052-1055
The migration and evolution of a deep ocean hydrothermal event plume were tracked with a neutrally buoyant RAFOS float. The float remained entrained in the plume for 60 days, and the plume vorticity was calculated directly from the anticyclonic motion of the float. Concentrations of suspended particles, particulate iron, and dissolved manganese in the plume did not decay significantly during the 60 days, which indicates that event plumes would be easily detectable a year after formation. 相似文献
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49.
AEM Horta JP Barbas CC Marques MC Baptista MI Vasques RM Pereira RD Mascarenhas S Cavaco‐Gonçalves 《Reproduction in domestic animals》2010,45(6):e412-e416
The effect of vaginal administration of misoprostol plus terbutaline sulphate 6 h prior to artificial insemination (AI) upon the site of AI (vaginal or cervical) and fertility was studied using a total of 87 estrous synchronized Serra da Estrela ewes (control n = 42 and treated n = 45). Artificial insemination was performed using refrigerated semen at 54–55 h after sponge removal. Lambing rate (fertility) and prolificacy were compared between control and treated ewes. The effect of the site of semen deposition on fertility was also evaluated. Prolificacy rate was not different between control (1.5) and treated (1.59) ewes. The proportion of cervical AI achieved in control (45.2%) and treated (37.8%) ewes was not significantly different. Overall, fertility was significantly lower in control than in treated ewes (42.9% vs 64.4%; p < 0.04). Fertility following vaginal AI was significantly lower for control for than treated ewes (30.4% vs 60.7%; p < 0.03) but the difference was smaller and not significant for cervical AI (control 57.9% vs 70.6%). It was concluded that vaginal administration of misoprostol plus terbutaline sulphate 6 h prior to artificial insemination did not affect the proportion of cervical inseminations but significantly improved the fertility of treated ewes. Although needing confirmation, it was hypothesized that drugs might have induced local secretory modifications leading to an increase of cervical ability to retain more viable spermatozoa for fertilization. 相似文献
50.
在U形壳槽横向内力计算中,若不考虑槽底局部加厚对Φ=90°截面内力的影响,则计算所得的该截面弯矩绝对值偏小.温度变化对截面内力的影响较大,特别是温降引起多数截面的弯矩增加,而轴向力减少;温升引起Φ=90°截面弯矩与轴向拉力均增加,再考虑槽底局部加厚的影响,弯矩值还要增加.槽底局部加厚与温度变化的作用均不能忽略不计,否则,内力计算成果值会偏于不安全.用结构力学方法,推导出二者对内力影响的计算公式,并附有应用的算例. 相似文献