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61.
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   
62.
Liver fibrosis is a morphologic alteration that accompanies chronic liver diseases. Apart from analysis of liver biopsy specimens, there has been no means of diagnosing and evaluating the course of liver fibrosis in the dog. Several plasma markers, including transforming growth factor beta-1 (TGF-β1), are used to indicate liver fibrosis in humans, but none has been validated for use in dogs. There is a significant correlation between the presence and severity of hepatic fibrosis and the plasma concentration of TGF-β1 in humans with hepatic fibrosis and cirrhosis. The feasibility of using TGF-β1 as a marker for hepatic fibrosis in dogs was evaluated by comparing plasma concentrations in 29 healthy dogs and 18 dogs with liver disease. The plasma concentrations of TGF-β1, were 193 to 598 pg/mL in the healthy dogs, 143 to 475 pg/mL in the 7 dogs with mild hepatic fibrosis or none at all, and 427 to 1289 pg/mL in 11 dogs with moderate to severe hepatic fibrosis. The plasma concentrations of TGF-β1 in the dogs with moderate to severe fibrosis differed significantly (P < 0.001) from those in the other 2 groups, whereas the concentrations in the dogs with mild or no fibrosis did not differ significantly from those in the healthy dogs (P > 0.05). It was concluded that TGF-β1 is a potential plasma marker for hepatic fibrosis in dogs.  相似文献   
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64.
Liver disease can influence the metabolism of various other organs. Regarding the influence of liver diseases on muscles, only a few studies done on people exist. The goal of our study was to investigate the influence of liver diseases on muscles in dogs. Twenty-eight dogs with different liver diseases were investigated in this study. The diagnosis of muscle alteration was based on electromyography (EMG), creatine kinase serum activity, 3-methylhistidine serum concentration and a muscle biopsy in some cases. Our results suggest that liver diseases in dogs can be accompanied with muscle alteration. 3-Methylhistidine serum concentration as a new parameter for muscle destruction in dogs was significantly increased compared to clinical healthy dogs and was comparable to those concentrations in dogs with histologically confirmed myopathy of different types. The differentiation of the liver diseases into severe hepatitis, moderate hepatitis and liver tumours showed a significant elevation of 3-methylhistidine serum concentration in cases of liver tumours (P=0.03) and a tendency in cases of severe hepatitis (P=0.07). Based on our study we can conclude that liver diseases have an influence on muscles in dogs and 3-methylhistidine could be a useful parameter for muscle destruction.  相似文献   
65.
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   
66.
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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68.
实验利用鸭全血中单核细胞,粒细胞,血栓细胞及自然杀伤细胞对酵母细胞非特异性细胞毒性作用,检测了15日龄鸭胚到112日龄鸭非特异性细胞免疫的发生。实验结果表明,鸭胚孵出前1周的22日龄到孵出后3日龄是鸭非特异性细胞免疫的发生期;3 ̄112日龄鸭在正常的生理状态下非特异性细胞免疫水平没有明显的变化。  相似文献   
69.
The present study was conducted to evaluate the function of Bacillus subtilis-based direct-fed microbials (DFMs) on macrophage functions, i.e., nitric oxide (NO) production and phagocytosis in broiler chickens. DFMs used in this study were eight single strains designated as Bs2084, LSSAO1, 3AP4, Bs18, 15AP4, 22CP1, Bs27, and Bs278, and one multiple strain DFM product (Avicorr™) containing equal amount of Bs2084, LSSAO1 and 15AP4. NO concentrations were monitored in plasma and in the supernatants from the peripheral blood-derived monocytic cells (PBMC)-derived macrophages stimulated by either chicken recombinant interferon gamma (IFNγ) or lipopolysaccharide (LPS) from Escherichia coli or Salmonella typhi. In addition, phagocytosis of fluorescent beads and green fluorescent protein (GFP)-labeled Salmonella by PBMC-derived macrophage was assayed. Plasma NO levels were significantly higher in groups given 3AP4 or Bs27 diets compared with the control group at days 7 and 14. NO production by PBMC-derived macrophages stimulated with IFNγ or LPS was apparent, although the effect was strain-dependent. Phagocytosis of fluorescent beads or GFP-labeled Salmonella by macrophages was augmented in groups on DFM-supplemented diets compared with those fed the control diet. This study describes the immunomodulatory effects of Bacillus-based DFMs on innate immunity in broiler chickens.  相似文献   
70.
Exogenous application of thiamine (vitamin B1) during imbibition improved germination and seedling development of bean (Phaseolus vulgaris L. cv. Lasso) seeds, which were exposed to soaking injury by submergence. Leaching of the vitamin into the incubation medium was not increased in submerged seeds. However, translocation of the thiamine reserves from the cotyledons to the seedling axis was reduced in response to soaking injury. After exogenous application of free thiamine to the seeds, thiaminedi-phosphate (TDP), which is the physiologically active coenzyme form of thiamine, accumulated in the seedling axis of submerged seeds, suggesting an increased demand for thiamine-dependent metabolic reactions in these tissues. Limited oxygen supply of the seeds during the soaking period induces a shift from respiration to fermentation of carbohydrates. Neither thiamine-dependent ethanolic fermentation, nor ATP production or adenylate energy charge (AEC) of the seedling axis were affected by exogenous thiamine application, suggesting that there is no limitation of thiamine-dependent reactions in the energy metabolism of the seedlings. Thus the physiological mechanisms improving germination and seedling development of submerged seeds in response to thiamine seed treatment are still not clear.  相似文献   
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