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221.
Background: Thrombelastography (TEG) and indicators of secondary and tertiary hemostasis might be altered in dogs with endotoxemia. Hypothesis: Endotoxemia influences measures of coagulation in dogs. Animals: Ten healthy cross‐bred dogs. Material and Methods: Prospective laboratory study between controls (n = 5) receiving 0.9% saline IV and the study group (n = 5) treated with low‐dose lipopolysaccharide (0.02 mg/kg IV). Physical examination and sampling for measurement of leukocytes, platelets, and coagulation variables were performed at time points 0, 1, 4, and 24 hours. Coagulation variables included kaolin‐activated TEG, 1‐stage prothrombin time (OSPT), activated partial thromboplastin time (aPTT), fibrinogen, factor VIII, antithrombin, protein C, protein S, activated protein C (APC)‐ratio calculated from aPTT with and without presence of APC), and D‐Dimers. Results: Endotoxemia‐induced clinical signs included lethargy (n = 5/5), diarrhea (n = 4/5), emesis (n = 4/5), and abdominal pain (2/5). After 1 hour there was severe leukopenia (2.5 ± 0.7 × 109/L; mean ± SD, P < .0001) and a 2.2‐fold increase in D‐Dimers (0.81 ± 0.64 mg/L, P < .0001). After 4 hours there was hyperthermia (40.3 ± 0.4°C, P < .0001) and increases in OSPT (10.5 ± 2.7 seconds, P < .0001), aPTT (16.7±5.2 seconds, P= 0.002). A significant decrease in fibrinogen (1.5±1.0 g/L, P= 0.001), protein C (31 ± 33%, P <.0001), protein S (63 ± 47%, P < .0001), TEG α (58 ± 19, P= .007), and TEG maximal amplitude (50 ± 19 mm, P= .003) was seen compared with the controls. APC‐ratio rose significantly (2.5 ± 0.2, P < .0001) without exceeding the reference interval (n = 4/5). Conclusion and Clinical Importance: D‐Dimers are the earliest indicator for endotoxemia‐associated coagulation abnormalities followed by decreased protein C concentration. APC‐ratio and TEG were not good screening variables.  相似文献   
222.
Five groups of laying hens were treated with different gizzerosine doses (0, 2.5; 5.0; 7.5; 10.0 mg/kg/body weight of gizzerosine) daily over a 21-day period to determine the serum concentrations of 1.25-dihydroxycholecalciferol (1,25(OH)2D), total calcium, inorganic phosphorus and magnesium. Blood samples were taken on days 7, 14, and 21 of the experiment. The concentration of 1,25(OH)2D remained unchanged after day 7 in the gizzerosine-treated birds compared to the control group. After 14 days, it was significantly lower in the birds receiving. gizzerosine, compared with the control group. On day 21, 1,25(OH2)D concentrations were also significantly decreased in all 4 gizzerosine-treated groups compared with the control hens. The serum total calcium, inorganic phosphorus and total magnesium concentrations varied significantly, but irregularly, during the period of the study.  相似文献   
223.
Progress in establishing systemic pharmacological effects for fresh, crushed garlic (Allium sativum L) in humans has been hindered by (1) the inability to measure allicin bioavailability, (2) lack of direct evidence that allicin has significant systemic activity at doses of garlic normally consumed, and (3) lack of a model for an acute effect. We have addressed these problems by quantifying the increases in breath acetone and breath allyl methyl sulfide (AMS). The area under the 48 h curve was measured in humans after consumption of standardized garlic preparations, allicin, and allicin-derived compounds, at the equivalent of 7 g of crushed garlic. It was shown that the allyl thiosulfinates (mainly allicin) are solely responsible for breath AMS and increased breath acetone. Diallyl trisulfide, diallyl disulfide, ajoene, and S-allylmercaptocysteine, at isomolar dithioallyl, showed the same quantitative effects as allicin. Consumption of AMS at isomolar allyl also gave the same effects as allicin, indicating that AMS is the main metabolite of allicin and is an active metabolite. In conclusion, allicin and allicin-derived compounds are rapidly metabolized to AMS, a compound which stimulates the production of acetone and which can be used to measure the bioavailability of allicin and, hence, the ability of garlic supplements to represent fresh garlic.  相似文献   
224.
A damaging virus isolated in the Netherlands from lettuce was studied and compared with a virus isolated from dandelion orginating from Czechoslovakia. It was found to biologically resemble dandelion yellow mosaic virus incompletely described from dandelion and lettuce in Great Britain (Kassanis, 1944, 1947) and from dandelion in Germany (Hein, 1963). Mechanical transmission was greatly improved by buffer solution and transmission byMyzus persicae seemed to be in the non-persistent manner. Longevity in vitro of the virus hardly exceeded one day. Thermal inactivation was between 60 and 65 °C and the dilution end-point was between 10 000 and 100 000. It was still infectious in leaf material dried and stored over CaCl2 at 4 °C for 6 1/2 years. The virus was isolated and purified with difficulty and was found to consist of one type of spherical particle of ca 30 nm diameter, with a sedimentation coefficient of 159 S, a buoyant density of 1.42 g.cm?3 and an A260/A280 ratio of 1.67. An antiserum was prepared with a titre of 256 in the agar double-diffusion test. The virus could be identified in crude extracts from lettuce andChenopodium amaranticolor by enzyme-linked immunosorbent assay (ELISA), but not by agar double diffusion. It could only be visualized in crude sap in the electron microscope after trapping of virus particles on antiserum-coated grids. The virus cannot yet be assigned to any known virus group. It is of potential economic importance to lettuce because of its occurrence in widely differing regions in Europe, its aggressiveness and virulence on 22 out of 23 lettuce cultivars tested (and on endive) and its pathogenicity toLactuca genotypes which are resistant to lettuce mosaic virus and other important pathogens of lettuce. ‘Laibacher Eis’ was the only cultivar showing some tolerance.  相似文献   
225.
Summary

Previously we reported that expression of the Arabidopsis DREB1A gene in chrysanthemum conferred increased tolerance to low-temperature and dehydration stresses, and that transgenic plants in which the DREB1A gene was driven by the abiotic stress-inducible promoter, rd29A, were more tolerant than those plants in which the DREB1A gene was driven by the 35S Cauliflower Mosaic Virus (CaMV) promoter. To understand the molecular basis for this improved tolerance, we isolated 74 DREB1A regulon genes using suppression subtractive hybridisation, then compared their expression patterns in rd29A:DREB1A transgenic plants (rd29A plants) and in 35S:DREB1A transgenic plants (35S plants) under different stress conditions. Our results showed that the increased tolerance to low temperatures and dehydration in rd29A plants was attributed to increased levels of expression of different members of the DREB1A regulon. Levels of expression of 69% or 91% for members of the DREB1A regulon that showed upregulation in rd29A plants were highly correlated with the level of expression of DREB1A in response to low temperature or to dehydration, respectively. These results support the hypothesis that the increased tolerance of rd29A plants to abiotic stresses resulted from elevated expression of the DREB1A regulon.  相似文献   
226.
227.
1. Mutations in growth differentiation factor 9 (GDF9) and bone morphogenetic protein 15 (BMP15) are significantly associated with reproductive performance in mammals and the objective of the present study was to identify polymorphic sites and elucidate the association between genotypes in BMP15 and GDF9 and egg production.

2. Polymorphisms in BMP15 exon1 and GDF9 exon2 were detected by DNA sequencing and PCR-RFLP. Three SNPs were detected in each of BMP15 (A111G, C231T and C34T) and GDF9 (G593A, T824C and C896T). C34T leads to the substitution of Leu by Phe, which was predicted to affect protein function.

3. Results of the association analysis indicated that C34T had an effect on total egg production at 300 d of age (EN) and age at first laying (AFE). G593A affected EN and both C231T and C896T influenced AFE. The TGC1TGC1 diplotype in BMP15 had the highest EN.

4. In conclusion, EN may be significantly improved by marker-assisted selection of the BMP15 genotypes in maternal lines of Shaobo hens.  相似文献   

228.
Garfish, Belone belone (Linnaeus, 1761) is an elongate, slander fish inhabiting the Eastern Atlantic and Mediterranean Sea. These fish from the Belonidae (Actinopterygii) family have important commercial value for Croatian fisheries. Samples for research were collected from experimental hatching in the Novigrad Sea. Preparation techniques included fixation in buffered formalin, trypsin clearing and staining with alcian blue and alizarin red. As little is known of garfish osteology and bone morphology, the main goal of this study was to describe ossification process in garfish fry. At hatching, no skeletal structure is present. Newly-hatched larvae also had no osteological elements. Ossification started at 7 day post-hatching (DPH) [total length (TL) 18 mm] with head bones and vertebral neural arch. Head skeleton continued to develop mostly over the period from 7 to 10 DPH. At 21 DPH (TL 49 mm), ossification process seemed to be finished, but it was not possible to distinguish borders of all bones. The primary interest of our research was to understand the growth dynamics as well as transformation of supporting body elements from cartilage to bone. At the end, developmental characteristics and functional aspects of this formation in different fish species are discussed.  相似文献   
229.
230.
Xylitol is commonly used as sugar substitute in households. While it has numerous beneficial effects on human health, it is highly toxic to dogs. The goal of this study was to examine whether xylitol has similar deleterious effects, such as hypoglycaemia and acute hepatic failure, on cats. Our research included six healthy middle‐aged cats. Xylitol was dissolved in deionized water and administered p.o. at three doses (100, 500 and 1,000 mg/kg body weight). These dosages have been considered toxic and can cause liver failure or even death in dogs. After every xylitol administration, the basic health status and the blood glucose of cats were observed regularly. Additionally, prior to and 6, 24 and 72 hr after xylitol administration, blood samples were taken to check complete blood count, clinical biochemical parameters and enzymes such as ALT, ALKP, GGT, GLDH, bile acids, BUN, creatinine, phosphate, total protein, albumin, sodium and potassium. There were no significant changes (> .05) in any of the haematological or biochemical parameters. Blood glucose concentrations did not show any significant alterations, except at 1,000 mg/kg dose, where a mild but significant increase was observed, but it was in physiological range. Based on our results, xylitol did not induce toxic effects on cats.  相似文献   
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