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31.
基于最小化边界圆周补偿机制的形状图像检索方法,提取了目标区域的特征,补偿了目标最小化边界圆周下的背景区域特征,较仅基于目标区域的检索算法取得了更好的查准率和查全率。  相似文献   
32.
目的:观察莲心碱对大鼠局灶性脑缺血/再灌注损伤血清中白介素-1(IL-1)和肿瘤坏死因子a(TNFa)活性的影响,探讨其对大鼠脑缺血再灌注损伤保护作用的机制。方法:线栓法阻塞大鼠大脑中动脉2h/再灌注24h制备大鼠脑缺血再灌注损伤动物模型。将24只SD雄性大鼠,随机分为3组:假手术组、缺血再灌注组和莲心碱3mg·kg-1组,分别于术前30min、再灌注后、再灌注12h舌静脉注射莲心碱3mg·kg-1;再灌注24h后大鼠断头取血,分离血清,采用双抗体夹心ELISA法测定血清IL-1和TNFa的吸光度。结果:大鼠脑缺血2h,再灌注24h后,血清中IL-1和TNFa活性显著增加,莲心碱可显著降低缺血再灌注损伤大鼠血清IL-1和TNFa活性。结论:莲心碱可能通过降低IL-1和TNFa活性而发挥脑缺血的保护作用。  相似文献   
33.
LIN Chun-long 《园艺学报》2008,24(2):303-306
AIM:To find out the mechanism of focal adhesion kinase (FAK) facilitating human pulmonary artery smooth muscle cells (HPASMCs) proliferation.METHODS:HPASMCs were isolated from normal part of lungs of two carcinoma patients who undergone lung partial resection. Cultured HPASMCs stimulated by fibronection(40 mg/L) were passively transfected with ODNs, sense focal adhesion kinase (FAK), mismatch sense and antisense-FAK, respectively. Expression of FAK, Jun NH2-terminal kinase (JNK) and cyclin-dependent kinase2 (CDK2) proteins were detected by immunoprecipitation and Western blotting. Cell cycle and cell apoptosis were analyzed by flow cytometry. In addition, cytoplasma FAK expression was detected by immunohistochemistry staining.RESULTS:The protein expressions of FAK, JNK and CDK2 in HPASMCs decreased in FAK ASODNs group and increased in FAK SODNs group. Meanwhile, the proportion of cells at G1 phase decreased significantly in FAK SODNs group, while the cells at S phase increased significantly. In contrast, the proportion of cells at G1 phase was increased significantly in FAK ASODNs group. The level of cell apoptosis in FAK ASODNs group was higher. FAK expression in FAK SODNs group was strongly stained by immunocytochemistry, whereas that in FAK ASODNs group was weakly stained. CONCLUSION:The results suggest that FAK via JNK, CDK2 signaling pathway enhances HPASMCs proliferation.  相似文献   
34.
BACKGROUND: Various bone resorption markers in humans are useful for supporting the diagnosis of malignant skeletal pathology, with certain bone resorption markers appearing to be more discriminatory for detecting cancer-induced osteolysis than others. Canine osteosarcoma (OSA) is characterized by focal bone destruction, but a systematic investigation for determining which bone resorption marker best supports the diagnosis of OSA in dogs has not been reported. HYPOTHESIS: Dogs with OSA will have increased concentrations of bone resorption markers compared with healthy dogs and dogs with orthopedic disorders. Differences will exist among various bone resorption markers for their ability to support the diagnosis of malignant osteolysis in dogs with OSA. ANIMALS: Single time point, cross-sectional, cohort study including dogs with OSA (n = 20) or orthopedic disorders (n = 20) and healthy dogs (n = 22). METHODS: Basal concentrations of urine and serum N-telopeptide (NTx), urine and serum C-telopeptide (CTx), and urine deoxypyridinoline (DPD) were compared among all 3 groups. RESULTS: Compared with healthy dogs and dogs with orthopedic disorders, urine NTx, serum NTx, and serum CTx concentrations were significantly increased in dogs with OSA. For urine NTx and serum NTx, the calculated lower and upper 95% confidence limits in dogs with OSA did not overlap with dogs diagnosed with orthopedic disorders or healthy dogs. CONCLUSIONS AND CLINICAL IMPORTANCE: Of the markers evaluated in this study, urine NTx and serum NTx appear to be the most discriminatory resorption markers supporting the diagnosis of focal malignant osteolysis in dogs with OSA.  相似文献   
35.
基于Meyer小波的无穷可微性、急减性和消失矩性等重要性质,给出了高维张量积Meyer小波的一种新的分解形式.  相似文献   
36.
基于多特征的杂草逆向定位方法与试验   总被引:1,自引:0,他引:1  
提出了一种基于多特征的杂草逆向定位方法。以田间作物作为研究对象,将多目标杂草定位问题转换为单目标的作物定位问题。采用作物叶片HU不变矩与形状特征的识别准确定位出每一株作物,然后基于颜色特征将作物区域以外的绿色植物均认定为杂草。设计了一款小型杂草定位装置,并应用在宽幅喷药机上。田间试验结果表明,在喷药机工作速度为5 km/h时,该系统对于大豆田间杂草识别的准确率为90%以上,较好地解决了杂草定位与精细喷洒农药问题。  相似文献   
37.
在《混凝土结构设计规范》(GB50010—2002)中,新增加了一节(7.7.5):在板柱结构中柱节点传递剪力和不平衡弯矩的受冲切承栽力的设计方法。然而,在国内讨论这个课题的论文很少。本文讨论了文献中报导的试验结果,阐述了板的破坏形态和特征,基于剪应力线性分布假定,推导出校核由剪力传递不平衡弯矩系数知的公式,并对试验结果作了验证,文中提出了这类构件受冲切承栽力计算方法,按此方法计算所得值与国内外试验结果的符合程度较好,文中也验证了新规范(GB50010—2002)冲切计算公式的计算值偏于安全。  相似文献   
38.
Background: Proteinuria is a feature of pyometra‐associated renal dysfunction, but its prevalence and clinical relevance are not well characterized. Objectives: To define which subset of dogs with pyometra has clinically relevant kidney injury by quantification of proteinuria; light, immunofluorescence, and electron microscopic examination of kidney biopsy specimens; and measurement of urinary biomarkers. Animals: Forty‐seven dogs with pyometra. Ten clinically healthy intact bitches of comparable age. Methods: Prospective study. Routine clinicopathological variables including urinary protein to creatinine ratio (UPC) were analyzed. Validated assays were used to quantify urinary biomarkers for glomerular (urinary albumin, urinary immunoglobulin G, urinary C‐reactive protein, urinary thromboxane B2) and tubular function (urinary retinol‐binding protein, urinary N‐acetyl‐β‐d ‐glucosaminidase). Kidney biopsy specimens from 10 dogs with pyometra and dipstick urine protein concentrations of 2+ or 3+ were collected during ovariohysterectomy. Urinalysis was repeated within 3 weeks after surgery in 9 of the 10 dogs. Results: UPC (median, range) was significantly higher in dogs with pyometra (0.48, 0.05–8.69) compared with healthy bitches (0.08, 0.02–0.16) (P < .01). Twenty‐two of 47 dogs with pyometra had UPC>0.5, 12 had UPC>1.0, and 7 had UPC>2.0. Glomerulosclerosis and tubulointerstitial nephritis were common kidney biopsy findings in proteinuric dogs with pyometra. Dogs with glomerulosclerosis (5/10), either global or focal and segmental, had UPC>1.0 at ovariohysterectomy and afterward. Dogs with structural glomerular and tubular changes mostly had urinary biomarker to creatinine ratios above the 75th percentile. Conclusion: Dogs with pyometra and UPC>1.0 or high ratios of urinary biomarkers appear likely to have clinically relevant renal histologic lesions and require monitoring after ovariohysterectomy. Future studies should evaluate the role of pyometra‐associated pathogenic mechanisms in causing or exacerbating focal and segmental glomerulosclerosis in dogs.  相似文献   
39.
Reasons for performing study: Recent research indicates that the digital joints experience some degree of extrasagittal motion during stance and that the moments under the hoof are asymmetric in horses walking in a straight line. On a circle, these have not been defined. Objectives: To quantify the amplitude and symmetry of horizontal twisting moments around the vertical axis through the hoof's centre of pressure on left and right circles at walk. Methods: Six Thoroughbred horses were led at walk across a Kistler force platform on a left and a right circle of 5 m radius. The resultant moment around the hoof was calculated from the 4 horizontal forces and their moment arms. Results: Five of the 6 horses exerted an internal moment around their left forehoof, and 4 exerted an internal moment around their right forehoof on the left circle. On the right circle, 5 of the 6 exerted an internal moment around the left forehoof and a weak external moment around the right forehoof. The moments under the hind hooves were bilaterally similar for right and left circles. Conclusion: Intrahorse variability in the applied moments is low, but there is some interhorse variability, especially in the forelimb moments, that indicates future studies of movements of the distal limb joints should be bilateral to account for mechanical asymmetry. Potential relevance: The finding that horizontal moments vary between forelimbs in some horses will apply to how exercise on a circle is approached, especially in rehabilitation programmes for horses with orthopaedic injury of the distal limb.  相似文献   
40.
Aliya  LIN Wu  HE Qiang 《园艺学报》2011,27(4):688-694
AIM: To construct a recombinant retroviral vector of short interfering RNA targeting focal adhesion kinase (FAK) gene and to establish a cell line with stable knockdown of FAK.METHODS: The oligonucleotides that transcribed to short hairpin RNA (shRNA) targeting FAK gene were synthesized in vitro, cloned into retroviral vector pSuper.retro and transfected into Phoenix cell line. The stable clones were screened and high-titer virus was produced. The human hepatocellular carcinoma cell line HCC-LM3 was infected with the virus-rich supernatant. The stable LM3 cell line, which showed significantly to silence FAK and associated proteins, was selected by puromycin.RESULTS: The recombinant retroviral vector was successfully constructed. Persistent knockdown of FAK in the LM3 cell line infected with the supernatant containing the retrovirus was confirmed by Western blotting. Down-regulation of FAK resulted in the inhibition of p-Akt and p-MAPK1/2 expression and led to decreased migration and invasion of the cells. The cell cycle was blocked at G0/G1 phase, and apoptosis was increased. The proliferation rate also decreased significantly.CONCLUSION: FAK-shRNA virus generated by recombinant retroviral vector pSuper-FAK can inhibit the protein expression of FAK and phosphorylation of Akt and MAPK1/2 in HCC-LM3 cells. Down-regulation of FAK shows a significant impact on biological behaviors of tumor cells.  相似文献   
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