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91.
Transmissible venereal tumor (TVT) is a well-documented transplantable tumor in dogs, with no breed or sex predilection and a low metastatic rate. In this report, a 2-year-old intact female Mastiff that had numerous, rapidly growing masses throughout the subcutis mainly at the dorsal body plane, the caudal half of the ventral abdomen, and around the vulva was euthanized due to poor prognosis. Neoplastic nodules similar to those seen in the subcutis were also noted in the lung, anterior mediastinum, liver, spleen, kidney, and superficial and deep lymph nodes in both abdominal and thoracic cavities. The neoplastic nodules from the subcutis as well as metastatic foci revealed similar cytologic and histologic features, which were consistent with canine TVT. By immunohistochemical staining, the neoplastic cells were positive for lysozyme and vimentin but were negative for cytokeratin, desmin, CD3, and CD79a. The diagnosis of the TVT was further supported by the identification and analysis of long interspersed nuclear elements (LINE) from paraffin-embedded tumor tissue. This case is a rare example of TVT with multiorgan metastasis. In this case, the polymerase chain reaction technique was useful in differential diagnosis of canine round cell tumors because this technique can be applied in retrospective as well as future study.  相似文献   
92.
93.
This study was conducted to determine the effect of addition of essential amino acids (EAA) to low-protein diets on N balance in barrows. Thirty barrows (Duroc × Yorkshire) with an initial BW of 36 kg were fed 5 corn- and soybean meal-based diets containing 13.6 to 18.2% crude protein (CP) for 10 d in a randomized complete block design. The 18.2% CP diet was formulated without addition of EAA (Lys, Met or Thr). The other diets contained 13.6 to 16.5% CP and were supplemented with EAA to provide 0.83% true digestible lysine equal to that in the 18.2% CP diet. Fecal, urinary, and total N excretion as well as N retention (g/d) decreased with decreasing dietary CP level (P < 0.01). The apparent digestibility of N was almost the same for the 18.2 and 16.5 CP diets, but the value was 2% higher (P = 0.07) than that for the 13.6% CP diet. These findings indicate that, compared with the 18.2% CP diets, supplementation with three EAA to the lowest-protein diets (13.6 CP) is inadequate for maximum intestinal protein digestion, amino acid absorption, or tissue protein deposition in growing barrows.  相似文献   
94.
运用生态学的系统分析方法,以铜川市耀州区金圣生态养羊示范基地农户肉羊农牧生态系统为研究对象,对系统的能量流动规律、种植业与养殖业的生态效率进行分析.分析表明三种规模养殖农户种植亚系统能量产投比与结构调整前相比分别提高了39.40%、39.50%和30.40%,向养殖亚系统输入的总能量占养殖亚系统需能总量的96.61%,88.45%和80.55%;养殖亚系统的能量转化效率分别达到7.35%、8.00%和8.39%,输入到种植亚系统的粪尿能水平分别是调整前粪尿能输入水平(37.64×103 MJ/hm2)的1.57倍、1.84倍和2.07倍.整个系统的经济投入与产出比分别达到1.73、1.83和1.98,三种规模农户的纯收益比调整前分别增加1132.5元、2392.8元和3913.5元.表明农户肉羊生产系统是一个高投入、高产出的农牧生态系统,有较好的生态效益和经济效益.  相似文献   
95.
The aim of the present study was to assess the clinical and histopathological findings in a canine model of ischemic stroke. Cerebral ischemic stroke was induced by middle cerebral artery occlusion in four healthy beagle dogs using silicone plugs. They showed neurological signs of forebrain dysfunction such as reduced responsiveness, head turning, circling, postural reaction deficits, perceptual deficits, and hemianopsia. These signs gradually regressed within 4 weeks without therapy. On magnetic resonance imaging, T2 hyperintensity and T1 hypointensity were found in the cerebral cortex and basal ganglia. These lesions were well-defined and sharply demarcated from adjacent brain parenchyma with a homogenous appearance. No abnormalities of the cerebrospinal fluid were observed. At necropsy, atrophic and necrotic lesions were observed in the cerebral cortex. The cerebral cortex, basal ganglia, and thalamus were partially unstained with triphenyl-tetrazolium chloride. Histopathologically, typical features of infarction were identified in cortical and thalamic lesions. This study demonstrates that our canine model resembles the conditions of real stroke patients.  相似文献   
96.
We previously induced protective immune response by oral immunization with yeast expressing the ApxIIA antigen. The ApxI antigen is also an important factor in the protection against Actinobacillus pleuropneumoniae serotype 5 infection; therefore, the protective immunity in mice following oral immunization with Saccharomyces cerevisiae expressing either ApxIA (group C) or ApxIIA (group D) alone or both (group E) was compared with that in two control groups (group A and B). The immunogenicity of the rApxIA antigen derived from the yeast was confirmed by a high survival rate and an ApxIA-specific IgG antibody response (p < 0.01). The highest systemic (IgG) and local (IgA) humoral immune responses to ApxIA and ApxIIA were detected in group E after the third immunization (p < 0.05). The levels of IL-1β and IL-6 after challenge with an A. pleuropneumoniae field isolate did not change significantly in the vaccinated groups. The level of TNF-α increased in a time-dependent manner in group E but was not significantly different after the challenge. After the challenge, the mice in group E had a significantly lower infectious burden and a higher level of protection than the mice in the other groups (p < 0.05). The survival rate in each group was closely correlated to the immune response and histopathological observations in the lung following the challenge. These results suggested that immunity to the ApxIA antigen is required for optimal protection.  相似文献   
97.
Mesenchymal stem cells (MSCs) have the capabilities for self-renewal and differentiation into cells with the phenotypes of bone, cartilage, neurons and fat cells. These features of MSCs have attracted the attention of investigators for using MSCs for cell-based therapies to treat several human diseases. Because bone marrow-derived cells, which are a main source of MSCs, are not always acceptable due to a significant drop in their cell number and proliferative/differentiation capacity with age, human umbilical cord blood (UCB) cells are good substitutes for BMCs due to the immaturity of newborn cells. Although the isolation of hematopoietic stem cells from UCB has been well established, the isolation and characterization of MSCs from UCB still need to be established and evaluated. In this study, we isolated and characterized MSCs. UCB-derived mononuclear cells, which gave rise to adherent cells, exhibited either an osteoclast or a mesenchymal-like phenotype. The attached cells with mesenchymal phenotypes displayed fibroblast-like morphologies, and they expressed mesenchym-related antigens (SH2 and vimentin) and periodic acid Schiff activity. Also, UCB-derived MSCs were able to transdifferentiate into bone and 2 types of neuronal cells, in vitro. Therefore, it is suggested that the MSCs from UCB might be a good alternative to bone marrow cells for transplantation or cell therapy.  相似文献   
98.
架面不同部位对无核剂处理木纳格葡萄无核化效果的影响   总被引:2,自引:0,他引:2  
用无核剂在花前、花后两次浸渍白木纳格和红木纳格葡萄花序和果穗,结果表明,架面各部位的花期没有明显差异,红木纳格花期更集中.架面前部的白木纳格、红木纳格可获得98.7%、93.8%的无核果率和7.36g、7.41g的果实粒重,架面中后部的果实无核果率、果粒重等品质有不同程度的下降.  相似文献   
99.
The biosynthesis of N-hydroxycinnamic acid amides (HCAAs), such as feruloyltyramine, p-coumaroyltyramine, feruloylserotonin, and p-coumaroylserotonin, in pepper plants was investigated in view of the activity of their corresponding enzymes and substrate levels. Almost all HCAAs were found in flowers, whereas the enzyme activity essential for HCAA biosynthesis seemed to be expressed constitutively in all tissues tested. The highest levels of the biogenic amines tyramine and serotonin, the key amine substrates, were also found in flowers, indirectly suggesting that the amine substrates play an important regulatory role in the synthesis of HCAAs.  相似文献   
100.
AIM: To study the mechanism of protective effect of exogenous carbon monoxide (CO) in the lung injury induced by ischemia-reperfusion (IR) of hind limbs in rats. METHODS: Thirty-two SD rats were randomly divided into 4 groups: control, control+CO, IR and IR+CO. A rat model of ischemia in hind limbs and the reperfusion lung injury was made. The rats in IR+CO and control+CO groups were exposed to air containing 2.5×10-8 CO for 1 h before reperfusion or the corresponding control time point, while the other two groups were exposed to the routine air. The lung tissue structure, polymorphonuclear leukocyte (PMN) count, wet-to-dry weight ratio (W/D), malondialdehyde (MDA) content and the animal survival rate were observed. The carboxyhemoglobin (COHb) levels in artery blood were detected with CO-oximeter and the expression of intercellular adhesion molecule-1 (ICAM-1) in the lung was detected by Western blotting. RESULTS: Compared to control, the animal mortality, lung PMNs number, W/D, MDA content and ICAM-1 expression were all significantly increased in IR group. Compared with the IR group, the blood COHb level was significantly increased and the animal mortality, lung PMNs number, W/D, MDA content and ICAM-1 expression were all significantly decreased in IR+CO group. CONCLUSION: These data suggest that exogenous CO attenuate limb IR-induced lung injury by down-regulatiny ICAM-1 expression and suppressing PMN sequestration in the lung following limb IR in rats.  相似文献   
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