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排序方式: 共有1155条查询结果,搜索用时 15 毫秒
971.
旨在评估普通T形骨板内固定治疗玩具犬桡尺骨远端骨折的临床效果及并发症。回顾了在中国农业大学动物医院采用开放式复位和普通T形骨板内固定治疗桡尺骨远端骨折的玩具犬的病历记录,并对这些病例进行回访。入选病例满足:体重不超过7 kg;骨折位置位于前臂远端(远端骨段与桡骨长度比值<0.25);回访时间>12个月;病例信息记录完整。结果表明:共纳入29只犬的29例桡尺骨远端骨折,26例(89.7%)术后无跛行,3例(10.3%)术后勉强可见跛行。未发生严重并发症,轻微并发症的发生率是20.7%(n=6)。普通T形骨板内固定能有效治疗玩具犬桡尺骨远端骨折,临床效果良好,无严重并发症。  相似文献   
972.
Enumeration of circulating tumour cells (CTC) has shown promise for prognostication and guidance of therapeutic decisions in human cancers. The objective of this study was to enumerate CTC over time in dogs with naturally occurring osteosarcoma (OSA), and to determine correlation with patient outcome. Twenty-six dogs with OSA and no evidence of metastatic disease at the time of amputation were enrolled. Dogs were assessed for lung metastases and CTC prior to and following amputation, and at each chemotherapy visit. Twenty-one dogs completed the study. Nineteen dogs were euthanized and two were alive and free of metastases. Overall survival time ranged from 88 to 1058 days (median survival time (MST) 374 days). Increased serum alkaline phosphatase activity, advanced age, and higher body weight were significantly associated with lower MST. Dogs with OSA had a mean of 356 (0 to 4443) CTC/106 leukocytes. In 12 of 15 dogs that developed radiographic evidence of metastasis, a pre-metastatic CTC spike was retrospectively detectable on average 36.5 (1–100 days) days prior to metastasis and was associated with significantly shorter MST (301 ± 64 vs. 626 ± 55 days; p = .0107). In a multivariable analysis, dogs with a CTC spike were 10× more likely to die compared with those without. These results suggest that a spike in CTC frequency precedes detection of metastasis in dogs with OSA and is associated with shorter survival. More frequent enumeration of CTC in a larger cohort of dogs with OSA may be warranted.  相似文献   
973.
A 12-year-old mixed-breed neutered female dog was referred with cutaneous tumors at the left auricle. Histologically, the cutaneous tumor located in the dermis comprised numerous clefts and cavernous channels lined by neoplastic endothelial cells with no erythrocytes. Bone tissue without direct contact with neoplastic cells was seen in the well-developed stromal connective tissue. The neoplastic endothelial cells exhibited mild to moderate atypia. Immunohistochemically, neoplastic cells were positive for vimentin and negative for cytokeratin and factor VIII-related antigen. Basement membrane around the neoplastic lumens was positive for laminin in a linear or granular pattern. Ultrastructural examination revealed discontinuous basement membrane beneath the tumor cells. Histopathological features of this case were consistent with lymphangiosarcoma, and stromal ossification was characteristic.  相似文献   
974.
老年性骨质疏松模型小鼠的颅骨增龄性变化   总被引:1,自引:0,他引:1  
为对比观察快速衰老型小鼠(SAMP6)与正常老化型小鼠(SAMR1)颅骨的增龄性变化,本试验采用活体micro-CT扫描定量观察SAMP6和SAMR1小鼠24、30、36周龄时的颅骨骨体积密度(BV/TV)。小鼠36周龄完成micro-CT扫描后,解剖颅骨,HE染色和抗酒石酸酸性磷酸酶(TRAP)染色对比观察小鼠颅骨组织学特点并测量破骨细胞数目。结果显示,不同年龄SAMP6的颅骨BV/TV值均显著低于同龄SAMR1;随年龄增长,SAMP6颅骨BV/TV显著降低,而SAMR1颅骨BV/TV无显著变化;与SAMR1相比,SAMP6颅骨内外骨板更薄,板障更宽;板障内破骨细胞更多,且差异显著。本试验表明随年龄增长,SAMP6的颅骨骨体积密度降低,且均小于同龄SAMR1,而SAMR1的无显著变化。  相似文献   
975.
Canine mesenchymal cells (MSCs) derived from Wharton''s jelly were co-cultured, then supplemented or not supplemented with platelet rich plasma (PRP) and demineralized bone matrix (DBM) to verify osteogenic differentiation. Osteoblastic differentiation followed by mineralized bone matrix production was found to be significantly higher (p < 0.05) when MSCs were associated with PRP/DBM in culture after 14-21-days of induction. Osteopontin and osteocalcin gene expression were significantly superior (p < 0.05) under the same culture conditions after 21 days of observation. In conclusion, addition of PRP to DBM co-cultured with MSCs successfully induced osteogenesis in vitro.  相似文献   
976.
977.
Official guidelines do not consider bone marrow (BM) assessment mandatory in staging canine lymphoma unless blood cytopenias are present. The aim of this study was to find out if blood abnormalities can predict marrow involvement in canine large B‐cell lymphoma. BM infiltration was assessed via flow cytometry. No difference was found between dogs without haematological abnormalities and dogs with at least one. However, the degree of infiltration was significantly higher in dogs with thrombocytopenia, leucocytosis or lymphocytosis and was negatively correlated to platelet count and positively to blood infiltration. Our results suggest that blood abnormalities are not always predictive of marrow involvement, even if thrombocytopenia, leucocytosis or lymphocytosis could suggest a higher infiltration. BM evaluation should therefore be included in routine staging in order not to miss infiltrated samples and to improve classification. However, its clinical relevance and prognostic value are still not defined and further studies are needed.  相似文献   
978.
本研究旨在观察不同代次骨髓间充质干细胞(BMSCs)和脂肪间充质干细胞(ADSCs)体外培养的生长特点和体外诱导成骨能力。通过密度梯度离心和贴壁培养法分离培养大鼠骨髓间充质干细胞和脂肪间充质干细胞,用含地塞米松、抗坏血酸、β-甘油磷酸钠的培养液定向诱导传代细胞向成骨细胞分化,并利用茜素红染色、碱性磷酸酶染色及PCR方法检测成骨细胞。结果表明骨髓及脂肪间充质干细胞呈成纤维细胞样生长,增殖能力强,生长迅速。第5、10、15、20代BMSCs及ADSCs经诱导培养后茜素红染色呈阳性并且出现"矿化"、碱性磷酸酶活性强,随着细胞代次的递增,诱导后细胞碱性磷酸酶活性呈递减趋势;诱导后的两类细胞传代后细胞仍能继续分化,并形成正常的"矿化"结节,且碱性磷酸酶染色均弱于初次诱导。结果提示,BMSCs及ADSCs易于分离培养及体外扩增,诱导条件下成骨能力强且成骨细胞传代培养仍具有成骨能力,适合作为再生医学骨组织工程的种子细胞。  相似文献   
979.
Reason for performing study: Analysis was performed to examine a method for refining the preoperative prognosis for horses that had surgery to remove apical fractures of the proximal sesamoid bones (PSBs). Objectives: To determine if: 1) there was a difference in size or configuration of apical fractures between the different anatomical locations of the PSBs, which have been shown to affect the prognosis; and 2) the size or configuration could predict the prognosis for racehorses with these fractures. Methods: The study included 110 weanlings and yearlings and 56 training racehorses that underwent surgery to remove apical PSB fractures. Radiographs of the fractures were used for measurement of the abaxial and axial proportion and the abaxial to axial ratio, and race records were used to determine average earnings per start (AEPS) and total post operative starts. Analysis of variance and regression statistics were used to compare the fragment sizes between the specific PSBs on each of the limbs and compare size and configuration of the fractures to prognosis. Results: There was a significantly larger abaxial to axial ratio (more transverse fracture) for the forelimb medial sesamoids than for all other sesamoids in untrained racehorses (P = 0.03). There were no other significant differences in size. There was no relationship between fracture size or configuration and AEPS nor total post operative starts. Conclusions: Apical fractures in weanlings and yearlings tend to be more transverse in the forelimb medial PSBs than the other PSBs. Apical fracture size and geometry does not determine prognosis for apical sesamoid fractures. Potential relevance: Horses that undergo surgery to remove larger apical fractures of the PSBs do not have a worse outcome than those horses with smaller fractures.  相似文献   
980.
用睾酮诱导,研究小鼠骨髓巨噬细胞(BMMs)凋亡过程中Fas/FasL途径上caspase-8表达的改变。以BMMs经L929条件培养基(LCM)诱导5d后,用流式细胞仪分选出F4/80阳性细胞,并将细胞分为两大组。第1组是空白对照组,睾酮(100nmol·L-1,下同)处理组,去除LCM组,去除LCM同时用睾酮处理组。第2组用FADD反义寡核苷酸(ASODN)转染BMMs后,重复第1组的4个处理组,并以FADD错义寡核苷酸(MSODN)转染后的睾酮处理组作为对照。处理12h后,用流式细胞仪检测巨噬细胞的凋亡情况,并通过RT-PCR、Real-timeRT-PCR和WesternBlot方法检测各组中caspase-8基因及蛋白的表达。结果显示,在缺少LCM或用睾酮处理时,睾酮可在体外诱导小鼠骨髓巨噬细胞凋亡,并伴随caspase-8的活化。FADD反义寡核苷酸能抑制睾酮诱导的小鼠骨髓巨噬细胞的凋亡,其下游的caspase-8表达也被抑制。  相似文献   
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