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21.
BACKGROUND: Canine splenic hemangiosarcoma (HSA) is a fatal malignancy, and most affected dogs die within a few months of diagnosis. Most dogs present with signs from tumor rupture, resulting in hemoabdomen and intra-abdominal dissemination. The abdomen is also the main site of disease recurrence. HYPOTHESIS: Intraperitoneal (IP) administration of doxorubicin will delay or prevent intra-abdominal tumor recurrence and prolong survival in dogs with HSA. ANIMALS: Fourteen dogs with splenic HSA. METHODS: A prospective, unmasked, uncontrolled clinical trial. After staging of disease status and splenectomy, pegylated liposomal encapsulated doxorubicin was administered intraperitoneally (1 mg/kg body weight) every 3 weeks for 4 cycles. All dogs were monitored for recurrence of HSA. Samples of plasma and abdominal fluid were collected for measurement of doxorubicin concentration and pharmacokinetic analysis. Nonlinear mixed-effect modeling was used to describe the pharmacokinetics of liposomal doxorubicin administered IP. RESULTS: All 14 dogs died, 12 because of HSA and 2 from other causes. Postmortem examination was performed on 12 dogs. All 12 dogs died because of HSA-related causes and had hepatic metastases and hemoabdomen. The IP-treated dogs had fewer serosal, mesenteric, and omental metastases than historical controls treated with systemic doxorubicin. Results of the postmortem examination and pharmacokinetic analysis confirmed that IP delivery of doxorubicin resulted in an effective drug concentration with a clearance comparable with that after i.v. delivery. CONCLUSIONS AND CLINICAL IMPORTANCE: IP pegylated liposomal encapsulated doxorubicin administration did not prevent intraabdominal recurrence of HSA in dogs.  相似文献   
22.
Rubber mats covering concrete slatted flooring are a developing market in dairy barns but remain rare in beef cattle facilities. The aim of this study was to investigate the effects of covering slatted concrete floor with perforated rubber mats on behaviour and occurrence of skin and claw lesions in fattening bulls. The groups of six bulls each with a total average age of 9.8 months were kept over 1 year on either slatted concrete (CONCRETE PEN) or on slatted concrete covered completely (RUBBER PEN) or partially (CHOICE PEN) with perforated rubber mats. Every quarter-year, behaviour (preference of flooring, lying, aggression, mounting) was recorded. In two-weekly intervals the incidence of skin lesions was examined. At 12 and 18 months of age the rising time of the bulls was measured. At the beginning of the study and after slaughter claw dimensions were recorded. Bulls in the CHOICE PEN preferred (P<0.01) the rubber coated area throughout the experiment. Animals in the RUBBER and the CHOICE PENS showed more lying periods (P<0.01) and had a lesser incidence of skin lesions (P<0.01) compared to bulls in the CONCRETE PEN. Bulls in the CHOICE PEN needed less time for rising (2.7+/-0.3s) than bulls in the CONCRETE PEN (4.4+/-0.5s, P<0.01). Net claw growth differed significantly between all pens (RUBBER>CHOICE>CONCRETE; P<0.05). In conclusion, the results of this study indicate that rubber coated slatted flooring has a positive influence on the housing conditions of beef cattle.  相似文献   
23.
All feces produced during 24 h were collected from five pigs and cortisol and immunoreactive cortisol metabolites (CICM), and IgA were quantified. Within pigs, the concentrations of CICM and IgA varied extensively between random samples obtained from a single fecal dropping, and deviated in most cases significantly from the true concentration measured in total fecal output (CV 6.7-130%). The CICM and IgA contents varied considerably (CV 8.1-114%) within and between individual fecal droppings from the same pig compared to the total fecal excretion. In conclusion, single random samples could not be used to reliably quantify the total fecal concentration or excretion of CICM or IgA in pigs. Analyses of all feces collected during shorter periods than 24 h did not provide an accurate estimate of the daily excretion of CICM. Thus, the concentration of stress sensitive molecules in random single fecal samples as an indicator of animal welfare should be interpreted with prudence.  相似文献   
24.
25.
A 5-year-old Quarter Horse mare was presented to the Michigan State University Equine Surgery Service for evaluation of a right hind metatarsophalangeal joint injury. On presentation, the horse was a grade 4/5 lame. Radiographs and ultrasonography showed peritendinous ossification/mineralisation of soft tissue structures and digital flexor tenosynovitis with profound intracapsular mineralisation. A digital flexor tendon sheath tenoscopy was performed with a plantar annular ligament desmotomy and a manica flexoria ligament tenotomy. During surgery, a significant amount of tan granular material was found within the digital tendon sheath. Approximately 80% of this material was removed, and a sample was sent for histopathology. The horse was diagnosed with eosinophilic granulomatous tenosynovitis. Long-term follow-up revealed improvement with four treatments of intralesional triamcinolone given 2–4 weeks apart. The horse became serviceably sound (grade 1/5) and was beginning light work under the saddle approximately 5 months post-tenoscopy.  相似文献   
26.
The aim of this study was to evaluate the interaction between yield levels of nonleguminous crops and soil organic matter (SOM) under the specific conditions of organic and conventional farming, respectively, and to identify implications for SOM management in arable farming considering the farming system (organic vs. conventional). For that purpose, correlations between yield levels of nonlegume crops and actual SOM level (Corg, Nt, Chwe, Nhwe) as well as SOM‐level development were examined including primary data from selected treatments of seven long‐term field experiments in Germany and Switzerland. Yield levels of nonlegume crops were positively correlated with SOM levels, but the correlation was significant only under conditions of organic farming, and not with conventional farming treatments. While absolute SOM levels had a positive impact on yield levels of nonlegumes, the yield levels of nonlegumes and SOM‐level development over time correlated negatively. Due to an increased demand of N from SOM mineralization, higher yield levels of nonlegumes obviously indicate an increased demand for OM supply to maintain SOM levels. Since this observation is highly significant for farming without mineral‐N fertilization but not for farming with such fertilization, we conclude that the demand of SOM‐level maintenance or enhancement and thus adequate SOM management is highly relevant for crop production in organic farming both from an agronomical and ecological point of view. Under conventional management, the agronomic relevance of SOM with regard to nutrient supply is much lower than under organic management. However, it has to be considered that we excluded other possible benefits of SOM in our survey that may be highly relevant for conventional farming as well.  相似文献   
27.
过磷酸钙添加剂对猪粪堆肥温室气体和氨气减排的作用   总被引:22,自引:6,他引:22  
为研究不同比例过磷酸钙添加剂对畜禽粪便高温堆肥氨挥发和温室气体减排的作用,该文以猪粪和玉米秸秆为试验材料,以市售过磷酸钙肥料作为添加剂,在发酵仓中(单仓体积1.2m3)进行56d的好氧堆肥试验,监测堆肥过程中的温室气体和氨排放速率及堆体碳、氮损失率。结果表明:在初始物料中添加干质量3.3%~13.2%的过磷酸钙添加剂对减少堆体碳、氮损失,降低温室气体排放均有明显效果,但超过初始物料干质量的9.9%的过磷酸钙添加剂会对堆肥腐熟进程产生显著抑制作用;该试验中添加初始物料干质量3.3%~6.6%分别使堆肥56d的NH3、N2O和CH4排放量减少了24.1%~43.4%、22.2%~27.7%和22.4%~62.9%,总温室气体排放当量减少30%。猪粪和玉米秸秆堆肥中较适宜的过磷酸钙添加量是初始物料干质量的3.3%~6.6%。该文为过磷酸钙添加剂应用于实际堆肥工程提供理论依据。  相似文献   
28.
Invasion of non-native species is among the top threats for the biodiversity and functioning of native and agricultural ecosystems worldwide. We investigated whether the herbivory of the slug Arion vulgaris (formerly Arion lusitanicus; Gastropoda), that is listed among the 100 worst alien species in Europe, is affected by soil organisms commonly present in terrestrial ecosystems (i.e. earthworms—Annelida: Lumbricidae and arbuscular mycorrhizal fungi—AMF, Glomerales). We hypothesized that slug herbivory would be affected by soil organisms via altered plant nutrient availability and plant quality. In a greenhouse experiment, we created a simple plant community consisting of a grass, a forb, and a legume species and inoculated these systems with either two earthworm species and/or four AMF taxa. Slugs were introduced after plants were established. Earthworms significantly reduced total slug herbivory in AMF-inoculated plant communities (P?=?0.013). Across plant species, earthworms increased leaf total N and secondary metabolites, AMF decreased leaf thickness. Mycorrhizae induced a shift in slug feeding preference from non-legumes to legumes; the grass was generally avoided by slugs. AMF effects on legume herbivory can partly be explained by the AMF-induced increase in total N and decrease in C/N ratio; earthworm effects are less clear as no worm-induced alterations of legume plant chemistry were observed. The presence of earthworms increased average AMF colonization of plant roots by 140 % (P?<?0.001). Total shoot mass was significantly increased by AMF (P?<?0.001). These data suggest that the feeding behavior of this invasive slug is altered by a belowground control of plant chemical quality and community structure.  相似文献   
29.
畜禽粪便固液分离技术特点及效率评估   总被引:1,自引:3,他引:1  
该文对常用畜禽粪便固液分离技术进行分析,评估出各分离技术的优缺点、适用对象、分离效果和性价比,为企业选择粪便固液分离设备提供参考。研究结果表明:重力分离技术成本最低,分离粒径小于1 mm的有机物效果最好,但分离后固相含水率过高(90%),一般作为其他技术的预处理。筛分技术对于分离大粒径的有机颗粒物最有效,投资相对小,运行费用低;但对氮磷等营养元素分离效率较低,分离后的固相的含水率偏高,分离产物可用于固态发酵。压滤技术提高了磷元素的分离效率和固相含水率,但运营成本也增加,分离产物可用于有机肥生产。沉淀离心技术对去除细小颗粒最为有效,并能够去除氮磷元素,但运营成本太高,在中国推广难度大。絮凝剂能和大多数的分离技术结合使用从而提高分离效率。所有固液分离技术都不能分离畜禽粪便中的挥发性脂肪酸,因此也不能有效去除液相中的生化需氧量和臭味。多种分离技术的联合使用,在提高营养物质的分离效率的同时,降低固相的含水率将是未来技术发展的主要方向。  相似文献   
30.
Recent investigations on the bitterness of coffee as well as 5- O-caffeoyl quinic acid roasting mixtures indicated the existence of another, yet unknown, bitter lactone besides the previously identified bitter compounds 5- O-caffeoyl- muco-gamma-quinide, 3- O-caffeoyl-gamma-quinide, 4- O-caffeoyl- muco-gamma-quinide, 5- O-caffeoyl- epi-delta-quinide, and 4- O-caffeoyl-gamma-quinide. In the present study, this orphan bitter lactone was isolated from the reaction products generated by dry heating of 5- O-caffeoylquinic acid model, and its structure was determined as the previously unreported 3- O-caffeoyl- epi-gamma-quinide by means of liquid chromatography-mass spectrometry (LC-MS) and one-/two-dimensional NMR experiments. The occurrence of this bitter lactone, exhibiting a low bitter recognition threshold of 58 micromol/L, in coffee beverages could be confirmed by LC-MS/MS (negative electrospray ionization) operating in the multiple reaction monitoring mode.  相似文献   
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