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151.
We characterized the pattern of ultrasonographic contrast enhancement of the small intestinal wall using a commercial contrast medium (Sonovue®) in 10 healthy awake cats. Subjectively, a rapid intense enhancement of the serosal and submucosal layers was followed by gradual enhancement of the entire wall section during the early phase. At peak enhancement, there was a subjective loss of demarcation between intestinal wall layers. In the late phase, there was a gradual wash out of signal from the intestinal wall. Submucosal wash out occurred last. Time‐intensity curves were generated for selected regions in the intestinal wall and multiple perfusion parameters were calculated for each cat. Perfusion parameters included arrival time (7.64 ± 2.23 s), baseline intensity (1.04 ± 0.04 a.u.), time to peak from injection (10.74 ± 2.08 s), time to peak from initial rise (3.1 ± 1.15), peak intensity (8.92 ± 3.72 a.u.), wash‐in rate (2.06 ± 0.70 a.u./s) and wash‐out rate (?1.07 ± 0.91 a.u./s). The perfusion pattern of normal feline small bowel may be useful for characterizing feline gastrointestinal disorders that involve the intestinal wall.  相似文献   
152.
Contrast‐enhanced ultrasonography is useful in differentiating adrenal gland adenomas from nonadenomatous lesions in human patients. The purposes of this study were to evaluate the feasibility and to describe contrast‐enhanced ultrasonography of the normal canine adrenal gland. Six healthy female Beagles were injected with an intravenous bolus of a lipid‐shelled contrast agent (SonoVue®). The aorta enhanced immediately followed by the renal artery and then the adrenal gland. Adrenal gland enhancement was uniform, centrifugal, and rapid from the medulla to the cortex. When maximum enhancement was reached, a gradual homogeneous decrease in echogenicity of the adrenal gland began and simultaneously enhancement of the phrenicoabdominal vessels was observed. While enhancement kept decreasing in the adrenal parenchyma, the renal vein, caudal vena cava, and phrenicoabdominal vein were characterized by persistent enhancement until the end of the study. A second contrast enhancement was observed, corresponding to the refilling time. Objective measurements were performed storing the images for off‐line image analysis using Image J (ImageJ©). The shape of the time–intensity curve reflecting adrenal perfusion was similar in all dogs. Ratios of the values of the cortex and the medulla to the values of the renal artery were characterized by significant differences from initial upslope to the peak allowing differentiation between the cortex and the medulla for both adrenal glands only in this time period. Contrast‐enhanced ultrasonography of the adrenal glands is feasible in dogs and the optimal time for adrenal imaging is between 5 and 90 s after injection.  相似文献   
153.
BACKGROUND: Current coagulation tests lack sensitivity and detect disseminated intravascular coagulation (DIC) only when it is severe. Measurement of antithrombin (AT) activity and D-dimer concentration permits early diagnosis and more precise classification of coagulopathies in some species. OBJECTIVES: The objectives of this study were to validate and determine the diagnostic utility of a chromogenic AT assay and an immunoturbidimetric D-dimer assay for the diagnosis of DIC in cats. METHODS: Citrated plasma samples were collected from 30 healthy cats, 30 ill cats, and 13 cats with cardiomyopathy. Partial thromboplastin time, prothrombin time, fibrin(ogen) degradation products, platelet concentration, and erythrocyte morphology were determined on all samples to document the presence or the absence of DIC. AT activity and D-dimer concentration were then measured. RESULTS: The chromogenic AT assay was linear and precise. Mean AT activity was higher in ill cats and cats with cardiomyopathy compared with healthy cats, but the difference was only significant in ill cats (P = .003). Seven cats met the criteria for DIC. Of the cats with DIC, 2 had decreased AT activity, 1 had increased AT activity, and 4 had AT activities within normal limits. The immunoturbidimetric D-dimer assay did not appear to accurately measure feline D-dimer. CONCLUSIONS: The chromogenic AT assay appeared to measure AT in cats but was not useful for the diagnosis of DIC. AT may be an acute phase reactant in cats. The immunoturbidimetric D-dimer assay was not useful for the diagnosis of DIC in cats.  相似文献   
154.
Background:  Many causes of mortality in the European brown hare, such as bacterial and viral infections, anticoagulant poisoning, and trauma, may result in hemorrhage. There are, however, no reference values concerning blood clotting in this species.  Objectives:  The aim of this study was to determine reference values for blood coagulation times and related parameters in healthy European brown hares.  Methods:  Blood samples from 30 clinically healthy adult hares (15 males and 15 females) were obtained. Hares were physically restrained for blood collection from the cephalic vein into tubes containing citrate and EDTA.  Results:  Mean ± SD were obtained for thrombin time (TT) (13.97 ± 1.37 seconds), prothrombin time (PT) (13.32 ± 2.15 seconds), activated partial thromboplastin time (APTT) (16.73 ± 1.86 seconds), fibrinogen concentration (2.98 ± 1.06 g/L), and platelet count (355.28 ± 128.73 × 109/L). Conclusions: Reference values for blood coagulation times and other parameters associated with blood clotting will be useful in the laboratory evaluation of hemorrhage in the European brown hare.  相似文献   
155.
A 2-year-old intact female miniature Pinscher weighing 1.7 kg with a body condition score of 2/5 was presented for acute vomiting, lethargy for 2 days, and large petechial skin lesions on the hip region including the tail. Acute pancreatitis was diagnosed by clinical signs, strong positive cPLI test, laboratory test and ultrasound appearance. While the clinical signs associated with acute pancreatitis had improved in 3–5 days, lesion of petechial appeared on the left hip region 7 days after the presentation, with a fast progression into a necrotic tissue along the left side hip. Allogenic platelet rich plasma (PRP) with Weibrich and Kleis method was administered to promote skin healing and regeneration. Gradual and complete improvement in the dog’s wound lesions was noted approximately 1 month after applying allogeneic topical PRP. In this case report, allogeneic PRP was applied to a large regional cutaneous defect caused by coagulopathy induced by acute pancreatitis. Topical application of PRP in this case was unique in that allogeneic PRP was used instead of autologous PRP for the first time in cutaneous soft-tissue wound management in the veterinary medical field.  相似文献   
156.

Background

Given the liver''s pivotal role in hemostasis and fibrinolysis, the coagulopathy accompanying hepatic disease is complex.

Hypothesis/Objectives

To prospectively evaluate kaolin‐activated thromboelastography (TEG) in dogs with acute liver disease (ALD) and compare with plasma‐based coagulation tests.

Animals

Twenty‐one dogs with a diagnosis of ALD based on recent onset of clinical signs accompanied by increases in serum bilirubin concentration and alanine aminotransferase activity.

Methods

Clinical presentation, CBC, serum biochemistry, platelet count, prothrombin time (PT), activated partial thromboplastin time (aPTT), and TEG analysis were evaluated in 21 dogs with a subset also having fibrinogen, antithrombin (AT) activity, protein C (PC) activity, d‐dimers, and von Willebrand''s factor (vWF) activity analyzed. A PT >1.5 times the upper limit of normal defined acute liver failure (ALF).

Results

Dogs with ALD had mean increases in R, K, LY30, PT, aPTT, and vWF activity, and decreases in angle, maximal amplitude (MA), G, AT activity, and PC activity. The TEG results defined dogs as hypocoagulable (11/21), normocoagulable (8/21), or hypercoagulable (2/21). Increases in LY30 defined 8/21 dogs as hyperfibrinolytic. Hypocoagulable and hyperfibrinolytic dogs had lower fibrinogen and PC activity than dogs without these abnormalities. Overall, ALF dogs had greater increases in K and LY30, and decreases in MA, G, and PC activity than dogs with less severe hepatic impairment. Results for MA and LY30 were positively correlated with serum bilirubin concentration and white blood cell count, and negatively correlated with serum cholesterol concentration.

Conclusions and Clinical Importance

ALD dogs have a range of coagulation abnormalities that trend toward hypocoagulability and hyperfibrinolysis as functional impairment occurs.  相似文献   
157.
Soil moisture has been considered as one of the main indicators that are widely used in the fields of hydrology, climate, ecology and others. The land surface temperature-vegetation index (LST-VI) space has comprehensive information of the sensor from the visible to thermal infrared band and can well reflect the regional soil moisture conditions. In this study, 9 pairs of moderate-resolution imaging spectroradiometer (MODIS) products (MOD09A1 and MODllA2), covering 5 provinces in Southwest China, were chosen to construct the LST-VI space, and then the spatial distribution of soil moisture in 5 provinces of Southwest China was monitored by the temperature vegetation dryness index (TVDI). Three LST-VI spaces were constructed by normalized difference vegetation index (NDVI), enhanced vegetation index (EVI), and modified soil-adjusted vegetation index (MSAVI), respectively. The correlations between the soil moisture data from 98 sites and the 3 TVDIs calculated by LST-NDVI, LST-EVI and LST-MSAVI, respectively, were analyzed. The results showed that TVDI was a useful parameter for soil surface moisture conditions. The TVDI calculated from the LST-EVI space (TVDIE) revealed a better correlation with soil moisture than those calculated from the LST-NDVI and LST-MSAVI spaces. From the different stages of the TVDIE space, it is concluded that TVDIE can effectively show the temporal and spatial differences of soil moisture, and is an effective approach to monitor soil moisture condition.  相似文献   
158.
【目的】施用腐殖酸尿素可以有效减少氮素NH3挥发损失,肥料中的腐殖酸发挥了很大作用,但是由于腐殖酸与尿素反应所得产物腐殖酸尿素复合物(UHA)对土壤NH3挥发的影响可能不同于常规腐殖酸(HA),进行相关研究将有利于揭示腐殖酸尿素降低土壤NH3挥发的机理。【方法】利用无水乙醇从腐殖酸尿素中提取得到UHA,在长期不施肥与长期施肥土壤上,开展室内恒温土壤培养试验,研究HA或UHA配施尿素对土壤NH3挥发的影响,二者的用量分别为尿素用量的0.5%与5%,分别用0.5HA+U、5HA+U、0.5UHA+U和5UHA+U表示,同时设置单施尿素(U)及不施尿素与腐殖酸处理(CK)。测定土壤NH3挥发速率及累积量,土壤尿素态氮、硝/铵态氮含量,土壤脲酶活性等。【结果】(1)各施氮处理,长期施肥土壤NH3挥发累积量均高于长期不施肥土壤,这可能与长期施肥导致土壤pH远低于不施肥土壤,土壤硝化过程减弱,尿素水解产生的铵态氮在土壤中累积有关。(2)HA或UHA配施尿素均可以有效降低土壤NH3挥发量,但是降低幅度与土壤是否长期施肥及二者用量有关:在长期不施肥土壤上,与单施尿素(U)相比,HA配施尿素土壤NH3挥发量可显著降低4.4%—22.9%(P<0.05),且5HA+U处理降低幅度大于0.5HA+U处理,但是在长期施肥土壤上,尿素配施HA处理,土壤NH3挥发量仅降低4.1%—7.5%,与U处理无显著差异;然而,尿素配施其用量0.5%的UHA,在长期不施肥与长期施肥土壤上均可以显著降低土壤NH3挥发累积量(P<0.05),土壤NH3挥发量较单施尿素处理分别降低26.5%与12.9%(P<0.05)。(3)HA降低土壤NH3挥发量可能与降低土壤脲酶活性有关,而UHA可能与促进土壤硝化过程有关。【结论】土壤培养条件下,与常规腐殖酸相比,腐殖酸尿素中的腐殖酸尿素复合物可更加有效地减少土壤NH3挥发量,且作用效果与土壤是否长期施肥无关。  相似文献   
159.
为了提高传统植物浮床对养殖水体的净化效果,降低养殖排放水污染,采用在凤眼莲Eichhornia crassipes浮床底部放置生物陶粒基质的方法构建强化生态浮床,研究了该强化生态浮床对养殖水体的净化效果。结果表明:用强化生态浮床净化水体16d时,对总氮(TN)、氨氮(NH+4-N)、亚硝氮(NO-2-N)、总磷(TP)、化学耗氧量(COD)的去除率分别达到48.57%、68.52%、77.05%、71.17%、47.22%,均显著高于凤眼莲组和生物陶粒组(P0.05);经强化生态浮床净化后的养殖水体中,TN、TP水平分别达到淡水池塘养殖排放水一级标准(SC/T9101—2007),NH+4-N浓度降至0.20mg/L以下,NO-2-N浓度降至0.01mg/L以下。研究表明,强化生态浮床中植物、基质和微生物的协同作用提高了其对污染物的去除效果。  相似文献   
160.
水稻近等不育系的涵义、选育及应用前景   总被引:1,自引:0,他引:1  
采用一种新方法,将表达增强型绿色荧光蛋白的大肠杆菌作为吞噬源,研究克氏原螯虾血细胞暴露于不同浓度的微囊藻毒素(Microcystin,MC)4 h后血细胞吞噬能力的变化,荧光倒置显微镜下观察具有吞噬能力的血细胞,以及血细胞对表达绿色荧光蛋白的大肠杆菌的整个吞噬过程.结果显示,各组血细胞的吞噬百分比没有显著性差异,空白组(L-15血细胞培养液+甲醇)中血细胞的吞噬百分比与对照组(L-15血细胞培养液)相比有上升趋势;处理组1(L-15血细胞培养液+1 μg/L MC-LR)、处理组2(L-15血细胞培养液+10 μg/L MC-LR)、处理组3(L-15血细胞培养液+100μg/L MC-LR)和处理组4(L-15血细胞培养液+1 000μg/L MC-LR)血细胞的吞噬百分比与对照组相比有下降趋势,并存在一定的剂量效应.对照组与空白组、4个处理组的吞噬指数均有显著性差异;其中对照组与处理组1~3的差异极显著,而空白组和4个处理组间没有显著性差异,处理组之间均没有显著性差异.结果表明,增强型绿色荧光蛋白能在大肠杆菌内稳定、持续地表达,可利用其直接观察血细胞的吞噬和包囊过程,能迅速、准确地得出吞噬百分比及吞噬指数;微囊藻毒素作用后,血细胞的吞噬指数显著降低,进而影响克氏原螯虾的免疫能力.  相似文献   
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