Colorimetric characterization is to transform the device-dependent responses to device-independent colorimetric values, and is usually conducted in CIEXYZ space. However, the optimal solution in CIEXYZ space does not ...Colorimetric characterization is to transform the device-dependent responses to device-independent colorimetric values, and is usually conducted in CIEXYZ space. However, the optimal solution in CIEXYZ space does not mean the mini-mization of perceptual error. A novel method for colorimetric characterization of imaging device based on the minimization of total color difference is proposed. The method builds the transform between RGB space and CIELAB space directly using the downhill simplex algorithm. Experimental results showed that the proposed method performs better than traditional least-square (LS) and total-least-square (TLS) methods, especially for colors with low luminance values.展开更多
Background Few data on ankle fractures in China from large multicenter epidemiological and clinical studies are available.The aim of this research was to evaluate the epidemiological features and surgical outcomes of ...Background Few data on ankle fractures in China from large multicenter epidemiological and clinical studies are available.The aim of this research was to evaluate the epidemiological features and surgical outcomes of ankle fractures by reviewing 235 patients who underwent ankle fracture surgery at five hospitals in China.Methods This study included patients who underwent ankle fracture surgery at five Chinese hospitals from January 2000 to July 2009.Age,gender,mechanism of injury,Arbeitsgemeinschaft für Osteosynthesefragen （AO） fracture type,fracture pattern,length of hospital stay and treatment outcome were recorded.Statistical analyses were conducted using SPSS software.The American Orthopedic Foot and Ankle Society （AOFAS） ankle-hindfoot scale,visual analogue scale （VAS）,and arthritis scale were used to evaluate outcome.Results Of 235 patients with ankle fractures,105 were male with an average age of 37.8 years and 130 were female with an average age of 47.3 years.The average follow-up period was 55.7 months.There were significant differences in the ratios of patients in different age groups between males and females,and in mechanisms of injury among different age groups.There were also significant differences in the length of hospital stay among different fracture types and mechanisms of injury.In healed fractures,the average AOFAS ankle-hindfoot score was 95.5,with an excellence rate of 99.6%,the average VAS score was 0.17,and the average arthritis score was 0.18.Movement of the injured ankle was significantly different to that of the uninjured ankle.There were no significant differences between AO fracture types,fracture patterns or follow-up periods and AOFAS score,but there were some significant differences between these parameters and ankle joint movements,pain VAS score and arthritis score.Conclusions Ankle fractures occur most commonly in middle-aged and young males aged 20-39 years and in elderly females aged 50-69 years.The most common mechanisms of injury are twisting injuries and falls from a standing height or less.The results of surgical treatment are satisfactory.展开更多
Background Cervical spondylotic myelopathy （CSM）, in part, results from degeneration of the posterior longitudinal ligament （PLL）, which mechanically compresses the spinal cord. Much research was done on the ossif...Background Cervical spondylotic myelopathy （CSM）, in part, results from degeneration of the posterior longitudinal ligament （PLL）, which mechanically compresses the spinal cord. Much research was done on the ossification of PLL, but not concerning the non-ossifying degeneration of cervical PLL. The degeneration of cervical PLL may be related to inflammation. The aim of this study was to elucidate the pathological features of the PLL and the role of cyclooxygenase 2 （COX-2） in the degeneration of the PLL in CSM. Methods A total of 23 PLL specimens were collected during surgery from patients with CSM for the histological and immunohistochemical （type II collagen and Ki-67） study. For the control group 14 cervical PLL autopsy specimens were investigated in the same manner, mRNA expression of COX-2 was quantitatively measured by real-time reverse transcription-polymerase chain reaction （RT-PCR） from 18 PLL specimens of patients with CSM and 18 PLL specimens of autopsy cases. Immunohistochemistry was used to evaluate the cellular location of COX-2 in PLL. Results A distinct amount of fibrotic area, chondrometaplastic tissue and calcification were found in the PLL of the patient group, compared with the control group. Type II collagen was apparent around chondrometaplastic cells. Ki-67 positive reaction was less than 5%. A COX-2 positive reaction was found in 9 of the patient specimens （39.1%） in which the COX-2 was released from vascular endothelial cells in the PLL. However, such reactions were not found in the control group. Real-time PCR showed that the mRNA expression level of COX-2 in the patient group was significantly higher than that in the control group （P〈0.01）. Conclusions Chondrometaplastic tissue producing type II collagen was identified as the most predominant pathological feature in the degenerative PLL. The higher expression of COX-2 might be related to degeneration of the PLL in CSM.展开更多
文摘Colorimetric characterization is to transform the device-dependent responses to device-independent colorimetric values, and is usually conducted in CIEXYZ space. However, the optimal solution in CIEXYZ space does not mean the mini-mization of perceptual error. A novel method for colorimetric characterization of imaging device based on the minimization of total color difference is proposed. The method builds the transform between RGB space and CIELAB space directly using the downhill simplex algorithm. Experimental results showed that the proposed method performs better than traditional least-square (LS) and total-least-square (TLS) methods, especially for colors with low luminance values.
文摘Background Few data on ankle fractures in China from large multicenter epidemiological and clinical studies are available.The aim of this research was to evaluate the epidemiological features and surgical outcomes of ankle fractures by reviewing 235 patients who underwent ankle fracture surgery at five hospitals in China.Methods This study included patients who underwent ankle fracture surgery at five Chinese hospitals from January 2000 to July 2009.Age,gender,mechanism of injury,Arbeitsgemeinschaft für Osteosynthesefragen （AO） fracture type,fracture pattern,length of hospital stay and treatment outcome were recorded.Statistical analyses were conducted using SPSS software.The American Orthopedic Foot and Ankle Society （AOFAS） ankle-hindfoot scale,visual analogue scale （VAS）,and arthritis scale were used to evaluate outcome.Results Of 235 patients with ankle fractures,105 were male with an average age of 37.8 years and 130 were female with an average age of 47.3 years.The average follow-up period was 55.7 months.There were significant differences in the ratios of patients in different age groups between males and females,and in mechanisms of injury among different age groups.There were also significant differences in the length of hospital stay among different fracture types and mechanisms of injury.In healed fractures,the average AOFAS ankle-hindfoot score was 95.5,with an excellence rate of 99.6%,the average VAS score was 0.17,and the average arthritis score was 0.18.Movement of the injured ankle was significantly different to that of the uninjured ankle.There were no significant differences between AO fracture types,fracture patterns or follow-up periods and AOFAS score,but there were some significant differences between these parameters and ankle joint movements,pain VAS score and arthritis score.Conclusions Ankle fractures occur most commonly in middle-aged and young males aged 20-39 years and in elderly females aged 50-69 years.The most common mechanisms of injury are twisting injuries and falls from a standing height or less.The results of surgical treatment are satisfactory.
文摘Background Cervical spondylotic myelopathy （CSM）, in part, results from degeneration of the posterior longitudinal ligament （PLL）, which mechanically compresses the spinal cord. Much research was done on the ossification of PLL, but not concerning the non-ossifying degeneration of cervical PLL. The degeneration of cervical PLL may be related to inflammation. The aim of this study was to elucidate the pathological features of the PLL and the role of cyclooxygenase 2 （COX-2） in the degeneration of the PLL in CSM. Methods A total of 23 PLL specimens were collected during surgery from patients with CSM for the histological and immunohistochemical （type II collagen and Ki-67） study. For the control group 14 cervical PLL autopsy specimens were investigated in the same manner, mRNA expression of COX-2 was quantitatively measured by real-time reverse transcription-polymerase chain reaction （RT-PCR） from 18 PLL specimens of patients with CSM and 18 PLL specimens of autopsy cases. Immunohistochemistry was used to evaluate the cellular location of COX-2 in PLL. Results A distinct amount of fibrotic area, chondrometaplastic tissue and calcification were found in the PLL of the patient group, compared with the control group. Type II collagen was apparent around chondrometaplastic cells. Ki-67 positive reaction was less than 5%. A COX-2 positive reaction was found in 9 of the patient specimens （39.1%） in which the COX-2 was released from vascular endothelial cells in the PLL. However, such reactions were not found in the control group. Real-time PCR showed that the mRNA expression level of COX-2 in the patient group was significantly higher than that in the control group （P〈0.01）. Conclusions Chondrometaplastic tissue producing type II collagen was identified as the most predominant pathological feature in the degenerative PLL. The higher expression of COX-2 might be related to degeneration of the PLL in CSM.
