AIM:To investigate effects of perirenal space blocking(PSB)on gastrointestinal function in patients with severe acute pancreatitis(SAP).METHODS:Forty patients with SAP were randomly allocated to receive PSB or no PSB(...AIM:To investigate effects of perirenal space blocking(PSB)on gastrointestinal function in patients with severe acute pancreatitis(SAP).METHODS:Forty patients with SAP were randomly allocated to receive PSB or no PSB(NPSB).All the SAP patients received specialized medical therapy(SMT).Patients in the PSB group received PSB+SMT when hospitalized and after diagnosis,whereas patients in the NPSB group only received SMT.A modifed gastrointestinal failure(GIF)scoring system was used to assess the gastrointestinal function in SAP patients after admission.Pain severity(visual analog scale,0 to100)was monitored every 24 h for 72 h.RESULTS:Modified GIF score decreased in both groups during the 10-d study period.The median score decrease was initially significantly greater in the PSB group than in the NPSB group after PSB was per-formed.During the 72-h study period,pain intensity decreased in both groups.The median pain decrease was significantly greater in the PSB group than in the NPSB group at single time points.Patients in the PSB group had significantly lower incidences of hospital mortality,multiple organ dysfunction syndrome,systemic inflammatory response syndrome,and pancreatic infection,and stayed in the intensive care unit for a shorter duration.However,no difference in terms of operation incidence was found between the two groups.CONCLUSION:PSB could ameliorate gastrointestinal dysfunction or failure during the early stage of SAP.Moreover,PSB administration could improve prognosis and decrease the mortality of SAP patients.展开更多
AIM: To evaluate the relationship between contrast sensitivity(CS) and corneal shape following overnight orthokeratology(OK). METHODS: We conducted a retrospective clinical study of 80 lens-wearing myopia patients, al...AIM: To evaluate the relationship between contrast sensitivity(CS) and corneal shape following overnight orthokeratology(OK). METHODS: We conducted a retrospective clinical study of 80 lens-wearing myopia patients, all of whom had undergone OK and had been evaluated by Orbscan II topography. We measured the surface irregularity index(SIRI) of corneal topography at 3 and 5 mm, the size of the flattened central corneal curvature of OK lens(zone A), the size of the cornea altered by OK lens(zone B), the size of the pupillary area at the corneal level(zone C), the area of crossover between zones A and C(zone AC), the area of crossover between zones B and C(BC), the ratio of BC to B(BC/B), and the ratio of AC to C(AC/C). CS was evaluated using the CSV-1000 with spatial frequencies of 3, 6, 12, and 18 cycles/degree(CPD). RESULTS: Multiple correlation analyses indicated significant negative correlations between CS, zone C, BC/B, and 3-mm SIRI(all P<0.01). There were no significant differences between CS, zone B, AC/A, or 5-mm SIRI(P=0.60, 0.94 and 0.11, respectively). Zone C was negatively correlated with 3, 6, 12, and 18 CPD. 5-mm SIRI were negatively correlated with 6, 12, and 18 CPD. BC/C was negatively correlated with 6 and 18 CPD. AC/C was positively correlated with 3 CPD. CONCLUSION: Zone C, 3-mm SIRI and BC/B affect the CS following overnight OK.展开更多
AIM:To evaluate the influence of age and axial length(AL) on the position of the fovea in patients with high myopia(HM).METHODS:In this prospective study,96 patients(186 eyes) with HM were consecutively recrui...AIM:To evaluate the influence of age and axial length(AL) on the position of the fovea in patients with high myopia(HM).METHODS:In this prospective study,96 patients(186 eyes) with HM were consecutively recruited from the Third Affiliated Hospital of Nanchang University.DRI-OCT Atlantis,fundus imaging,and IOL Master were used in this study.Three indices were measured:the distance between the fovea and the optic nerve head(ONH) center(DFO),the vertical distance between the fovea and the horizontal line pass of the ONH center(VDFO),and the horizontal distance between the fovea and the vertical line pass of the ONH center(HDFO).These measurements were used to analyze the effects of different age groups(A1,A2,A3 groups) and AL(AL1,AL2,AL3,AL4 groups) on these indices.RESULTS:The results showed that there was no statistical significance in DFO among the age and AL groups(F=0.46,0.37;P=0.62,0.76,respectively).In HDFO,there was also no statistical significance among the age and AL groups(F=0.10,0.48;P=0.90,0.69,respectively).In VDFO,however,the difference in the age and AL groups was statistically significant(F=3.21,3.12;P=0.04,0.02,respectively).Thus,VDFO were correlated with age and AL(r=0.21,0.23,all P〈0.01),while HDFO and DFO were not correlated with age and AL(r=0.30,P〉0.05).CONCLUSION:In high myopia,the foveal position changes mainly in the vertical direction along with factors of age and AL.展开更多
We fabricated Sb 2 Se 3 thin film solar cells using tris(8-hydroxy-quinolinato)aluminum(Alq 3)as an electron transport layer by vacuum thermal evaporation.Another small organic molecule of N,N'-bis(naphthalen-1-yl...We fabricated Sb 2 Se 3 thin film solar cells using tris(8-hydroxy-quinolinato)aluminum(Alq 3)as an electron transport layer by vacuum thermal evaporation.Another small organic molecule of N,N'-bis(naphthalen-1-yl)-N,N'-bis(phenyl)benzidine(NPB)was used as a hole transport layer.We took ITO/NPB/Sb 2 Se 3/Alq 3/Al as the device architecture.An open circuit voltage(V o c)of 0.37 V,a short circuit current density(J s c)of 21.2 mA/cm 2,and a power conversion efficiency(PCE)of 3.79%were obtained on an optimized device.A maximum external quantum efficiency of 73%was achieved at 600 nm.The J s c,V o c,and PCE were dramatically enhanced after introducing an electron transport layer of Alq 3.The results suggest that the interface state density at Sb 2 Se 3/Al interface is decreased by inserting an Alq 3 layer,and the charge recombination loss in the device is suppressed.This work provides a new electron transport material for Sb 2 Se 3 thin film solar cells.展开更多
Background: Desmoplastic fibroblastoma (collagenous fibroma) is an uncommon benign soft-tissue tumor, rarely involving bone. It shares some overlapping features with other infiltrate tumors, such as desmoid-type fi...Background: Desmoplastic fibroblastoma (collagenous fibroma) is an uncommon benign soft-tissue tumor, rarely involving bone. It shares some overlapping features with other infiltrate tumors, such as desmoid-type fibromatosis, neurofibroma, and low-grade fibromyxoid sarcoma. The misdiagnosis may cause unnecessary surgical overtreatment, especially for those involving bone. In order to deepen the understanding of the diagnosis and differential diagnosis of desmoplastic fibroblastoma, we planned to analyze the clinical, radiological, and histopathological features and the outcome of desmoplastic fibroblastoma on the basis of case analysis and literature review. Methods: Sixteen cases were retrieved from the surgical pathology records from May 2011 to April 2016 in the Department of Pathology in Beijing Jishuitan Hospital. Formalin-fixed, paraffin-embedded specimens of 16 cases of desmoplastic fibroblastoma were collected. Hematoxylin and eosin stain and immunohistochemistry were used to observe the histological features of desmoplastic fibroblastoma of soft tissue and bone. The images for diagnosis obtained from the ultrasonic examination, X-ray, magnetic resonance imaging, and computed tomography were used to observe the radiological features. Related literatures were retrieved from the PubMed and CNKI databases. Results: Sixteen cases of desmoplastic fibroblastoma of soft tissue were located in the hand (n = 7), loot (n = 4), upper arm (n = 1), shoulder (n = 1), forearm (n = 2), and one case occurred in the proximal femur. Age ranged from 32 to 82 years (median age: 58 years). There were six females and ten males. Histologically, the lesions of soft tissue appeared as well-circumscribed masses with abundant collagenous matrix and low vascularity. Tumor cells were stellate- or spindle-shaped and uniformly distributed within the extracellular matrix. In five cases, the desmoplastic fibroblastoma were found to have infiltrated into the skeletal muscle tissue. In one case ofdesmoplastic fibroblastoma of bone, radiographs revealed osteolytically well-defined lesion, lmmunohistochemistry stain showed that vimentin and smooth muscle actin were positive in all cases of desmoplastic fibroblastoma. Conclusions: Desmoplastic fibroblastoma (collagenous fibroma) has prominent clinical, histopathological, and radiological features. Before the differential diagnosis from other tumors is obtained by thorough analysis and comparison of the similar and different characteristics, the appropriate surgical management and accurate prognosis evaluation could not be delivered to the patient.展开更多
Background: Wide resection margins of osseous tumors are associated with a low incidence of local recurrence, making accurate measurement of the intraosseous extent of primary malignant long bone tumors is crucial. W...Background: Wide resection margins of osseous tumors are associated with a low incidence of local recurrence, making accurate measurement of the intraosseous extent of primary malignant long bone tumors is crucial. We compared the intraosseous tumor extent assessed by magnetic resonance imaging (MRI) with the gross specimen to evaluate the accuracy of MRI. Methods: A total of 255 patients with primary malignant tumors in the long bones were included. Using MRI, we defined the length of tumor as the distance from the articular surface to the boundary between abnormal and normal marrow signal. The extent of the abnormal intraosseous signal was measured on unenhanced T1-weighted (T1WI) magnetic resonance images after chemotherapy. All gross surgical specimens were sectioned, and tumor extent was measured. Wilcoxon signed-rank test was used to test the differences between MRI and gross specimen findings. Spearman's correlation analysis was used to test the correlation between groups. Results: Median tumor length by gross specimen (112 mm; range, 45–300 mm) was longer than that by MRI (108 mm; range, 45–304 mm;Z = -6.916, P 〈 0.001). Of 255 images, tumor length was accurately represented on 27 T1WI magnetic resonance images, overestimated on 79 images, and underestimated on 149 images. The median difference between imaging and gross specimen measurements was 2.0 mm (range: 1.0–15.0 mm) for the 79 cases where tumor length was overestimated, and 5.0 mm (range: 1.0–18.0 mm) for the 149 cases where tumor length was underestimated. The Spearman correlation demonstrated a high correlation of tumor length on gross specimen with the tumor length on MRI (R = 0.99, P 〈 0.01). Conclusions: We conclude that preoperative MRI could be a useful method in determining intramedullary malignant bone tumor boundaries and may serve as an accepted assessment method of long bone tumors before limb-sparing surgery.展开更多
Low frequency vibrations induced by underground railways have attracted increasing attention in recent years. To obtain the characteristics of low frequency vibrations and the low frequency performance of a floating s...Low frequency vibrations induced by underground railways have attracted increasing attention in recent years. To obtain the characteristics of low frequency vibrations and the low frequency performance of a floating slab track (FST), low frequency vibration tests on an FST in an underground laboratory at Beijing Jiaotong University were carried out. The FST and an unbalanced shaker SBZ30 for dynamic simulation were designed for use in low frequency vibration experiments. Vibration measurements were performed on the bogie of the unbalanced shaker, the rail, the slab, the tunnel invert, the tunnel wall, the tunnel apex, and on the ground surface at distances varying from 0 to 80 m from the track. Measurements were also made on several floors of an adjacent building. Detailed results of low frequency vibration tests were reported. The attenuation of low frequency vibrations with the distance from the track was presented, as well as the responses of different floors of the building. The experimental results could be regarded as a reference for developing methods to control low frequency vibrations and for adopting countermeasures.展开更多
Inexpensive,safe,and efficient conversion of solar energy to hydrogen from water splitting requires the development of effective and durable photocatalysts.Cu_(2)ZnSnS_(4)(CZTS),the emerging quaternary chalcogenide ma...Inexpensive,safe,and efficient conversion of solar energy to hydrogen from water splitting requires the development of effective and durable photocatalysts.Cu_(2)ZnSnS_(4)(CZTS),the emerging quaternary chalcogenide material for solar energy conversion,possesses many advantages,such as narrow direct band gap(1.5 eV),nontoxic,earth-abundance,and low melting point.Currently,CZTS-based photocatalysts have been extensively investigated for their application as an active photocatalyst in hydrogen evolution from water splitting,while the performance is still highly needed to be improved for the practical applications.In this review,first,the crystal and band structure properties of CZTS are briefly introduced,and afterward,the basic principle of photocatalytic hydrogen evolution from water splitting is discussed.Subsequently,the performance and status of bare CZTS,the combination of CZTS and co-catalysts,and CZTSbased heterojunction photocatalysts for hydrogen evolution are reviewed and discussed in detail.Finally,the issues and challenges currently encountered in the application of CZTS and their possible solutions for developing advanced CZTS photocatalysts are provided.展开更多
Synthetic mesh is often used in soft tissue reconstruction after artificial prosthesis replacement for patients with proximal humeral bone tumors.We carried out biomechanical and histological tests on two amputated ex...Synthetic mesh is often used in soft tissue reconstruction after artificial prosthesis replacement for patients with proximal humeral bone tumors.We carried out biomechanical and histological tests on two amputated extremities to test the stability of the joint and the biocompatibility of the synthetic meshes.展开更多
The interfacial oxidation behavior of Cr_(4)Mo_(4) V high-speed steel(HSS)joints undergoing hot-compression bonding was investigated by using optical microscopy(OM),scanning electron microscopy(SEM),and transmission e...The interfacial oxidation behavior of Cr_(4)Mo_(4) V high-speed steel(HSS)joints undergoing hot-compression bonding was investigated by using optical microscopy(OM),scanning electron microscopy(SEM),and transmission electron microscopy(TEM).In the heating and holding processes,dispersed rod-like and granularδ-Al_(2)O_(3) oxides were formed at the interface and in the matrix near the interface due to the selective oxidation and internal oxidation of Al,while irregular Si-Al-O compounds and spheroidal SiO_(2) particles were formed at the interface.After the post-holding treatment,SiO_(2) oxides and Si-Al-O compounds were dissolved into the matrix,andδ-Al_(2)O_(3) oxides were transformed into nanoscaleα-Al_(2)O_(3) particles,which did not deteriorate the mechanical properties of the joints.The formation and migration of newly-formed grain boundaries by plastic deformation and post-holding treatment were the main mechanism for interface healing.The tensile test results showed that the strength of the healed joints was comparable to that of the base material,and the in-situ tensile observations proved that the fracture was initiated at the grain boundary of the matrix rather than at the interface.The clarification of interfacial oxides and microstructure is essential for the application of hot-compression bonding of HSSs.展开更多
Background:The role of osteopontin(OPN)in intrahepatic cholangiocarcinoma(ICC)remains controversial.This study aimed to explore the prognostic value of OPN in patients with ICC undergoing curative resection.Methods:Pa...Background:The role of osteopontin(OPN)in intrahepatic cholangiocarcinoma(ICC)remains controversial.This study aimed to explore the prognostic value of OPN in patients with ICC undergoing curative resection.Methods:Patients undergoing curative resection from 2005 to 2016 were identified for inclusion in this retrospective study.The expression level of OPN in tumors was measured in each of the 228 patients by immunohistochemistry.Circulating OPN in serum was tested in 124 patients by ELISA.Tumor volume was calculated according to preoperative imaging or operation record.Proliferation assay,wound healing assay,and invasion assay were performed to investigate the biological function.Results:Low expression of OPN in tissue was associated with lymph node metastasis(P=0.009)and shorter overall survival(OS)(P=0.001).A low level of circulating OPN/volume was associated with multiple tumors(P<0.001),vascular invasion(P=0.027),visceral peritoneal perforation(P=0.001),and lymph node metastasis(P=0.002).It was also able to predict the invasive behavior,lymph node metastasis,and early recurrence with the area under the receiver operating curve(AUC)of being 0.719,0.708 and 0.622 respectively.Patients with a low level of circulating OPN/volume had shorter OS(P=0.028)and disease-free survival(DFS)(P=0.004)and could benefit from adjuvant chemotherapy(P=0.011).Compared with negative controlled cells,ICC cell lines,which expressed more OPN,showed a decelerated proliferation rate,the weaker ability of migration and invasion,while the opposite was true for the cells expressed less OPN.MMP1,MMP10,and CXCR4 were negatively regulated by OPN.Conclusions:A low level of circulating OPN/volume could indicate aggressive characteristics,along with poor prognosis and efficacy of adjuvant chemotherapy in ICC patients.Over expression of OPN may inhibit phenotypes facilitating ICC metastasis by negatively regulating MMP1,MMP10,and CXCR4.展开更多
基金financial supports from the National Key R&D Program of China (2018YFC1901604)the Natural Science Foundation of Hunan Province,China (2018JJ3662)+1 种基金the China Scholarship Council (201706375005)the China Postdoctoral Science Foundation (2018M632988)。
基金Projects(2018YFC1901601,2018YFC1901604,2018YFC1901605) supported by the National Key Research and Development Program of ChinaProject(201806375047) supported by the Visiting Scholar of China Scholarship CouncilProject(51404296) supported by the Young Scientists Fund of the National Natural Science Foundation of China
基金Project(2016M602427)supported by the Postdoctoral Science Foundation of ChinaProject supported by the Fundamental Research Funds for the Central Universities of Central South University,China
文摘AIM:To investigate effects of perirenal space blocking(PSB)on gastrointestinal function in patients with severe acute pancreatitis(SAP).METHODS:Forty patients with SAP were randomly allocated to receive PSB or no PSB(NPSB).All the SAP patients received specialized medical therapy(SMT).Patients in the PSB group received PSB+SMT when hospitalized and after diagnosis,whereas patients in the NPSB group only received SMT.A modifed gastrointestinal failure(GIF)scoring system was used to assess the gastrointestinal function in SAP patients after admission.Pain severity(visual analog scale,0 to100)was monitored every 24 h for 72 h.RESULTS:Modified GIF score decreased in both groups during the 10-d study period.The median score decrease was initially significantly greater in the PSB group than in the NPSB group after PSB was per-formed.During the 72-h study period,pain intensity decreased in both groups.The median pain decrease was significantly greater in the PSB group than in the NPSB group at single time points.Patients in the PSB group had significantly lower incidences of hospital mortality,multiple organ dysfunction syndrome,systemic inflammatory response syndrome,and pancreatic infection,and stayed in the intensive care unit for a shorter duration.However,no difference in terms of operation incidence was found between the two groups.CONCLUSION:PSB could ameliorate gastrointestinal dysfunction or failure during the early stage of SAP.Moreover,PSB administration could improve prognosis and decrease the mortality of SAP patients.
文摘AIM: To evaluate the relationship between contrast sensitivity(CS) and corneal shape following overnight orthokeratology(OK). METHODS: We conducted a retrospective clinical study of 80 lens-wearing myopia patients, all of whom had undergone OK and had been evaluated by Orbscan II topography. We measured the surface irregularity index(SIRI) of corneal topography at 3 and 5 mm, the size of the flattened central corneal curvature of OK lens(zone A), the size of the cornea altered by OK lens(zone B), the size of the pupillary area at the corneal level(zone C), the area of crossover between zones A and C(zone AC), the area of crossover between zones B and C(BC), the ratio of BC to B(BC/B), and the ratio of AC to C(AC/C). CS was evaluated using the CSV-1000 with spatial frequencies of 3, 6, 12, and 18 cycles/degree(CPD). RESULTS: Multiple correlation analyses indicated significant negative correlations between CS, zone C, BC/B, and 3-mm SIRI(all P<0.01). There were no significant differences between CS, zone B, AC/A, or 5-mm SIRI(P=0.60, 0.94 and 0.11, respectively). Zone C was negatively correlated with 3, 6, 12, and 18 CPD. 5-mm SIRI were negatively correlated with 6, 12, and 18 CPD. BC/C was negatively correlated with 6 and 18 CPD. AC/C was positively correlated with 3 CPD. CONCLUSION: Zone C, 3-mm SIRI and BC/B affect the CS following overnight OK.
基金Project(2016M602427)supported by the Postdoctoral Science Foundation of ChinaProject(51504292)supported by the National Natural Science Foundation of ChinaProject(2016zzts288)supported by Graduate Student Innovation Foundation of Central South University,China
基金Supported by the Research and Development Project of Science and Technology of the Jiangxi Province(No.20171BBG70100)the Ophthalmic Innovation Project of Nanchang City(No.2016114)
文摘AIM:To evaluate the influence of age and axial length(AL) on the position of the fovea in patients with high myopia(HM).METHODS:In this prospective study,96 patients(186 eyes) with HM were consecutively recruited from the Third Affiliated Hospital of Nanchang University.DRI-OCT Atlantis,fundus imaging,and IOL Master were used in this study.Three indices were measured:the distance between the fovea and the optic nerve head(ONH) center(DFO),the vertical distance between the fovea and the horizontal line pass of the ONH center(VDFO),and the horizontal distance between the fovea and the vertical line pass of the ONH center(HDFO).These measurements were used to analyze the effects of different age groups(A1,A2,A3 groups) and AL(AL1,AL2,AL3,AL4 groups) on these indices.RESULTS:The results showed that there was no statistical significance in DFO among the age and AL groups(F=0.46,0.37;P=0.62,0.76,respectively).In HDFO,there was also no statistical significance among the age and AL groups(F=0.10,0.48;P=0.90,0.69,respectively).In VDFO,however,the difference in the age and AL groups was statistically significant(F=3.21,3.12;P=0.04,0.02,respectively).Thus,VDFO were correlated with age and AL(r=0.21,0.23,all P〈0.01),while HDFO and DFO were not correlated with age and AL(r=0.30,P〉0.05).CONCLUSION:In high myopia,the foveal position changes mainly in the vertical direction along with factors of age and AL.
基金Supported by the High Level Talents Project of Hainan Basic and Applied Research Program(Natural Science)(Grant No.2019RC118)the Open Fund of the State Key Laboratory of Molecular Reaction Dynamics in DICP(Grant No.SKLMRD-K202005).
文摘We fabricated Sb 2 Se 3 thin film solar cells using tris(8-hydroxy-quinolinato)aluminum(Alq 3)as an electron transport layer by vacuum thermal evaporation.Another small organic molecule of N,N'-bis(naphthalen-1-yl)-N,N'-bis(phenyl)benzidine(NPB)was used as a hole transport layer.We took ITO/NPB/Sb 2 Se 3/Alq 3/Al as the device architecture.An open circuit voltage(V o c)of 0.37 V,a short circuit current density(J s c)of 21.2 mA/cm 2,and a power conversion efficiency(PCE)of 3.79%were obtained on an optimized device.A maximum external quantum efficiency of 73%was achieved at 600 nm.The J s c,V o c,and PCE were dramatically enhanced after introducing an electron transport layer of Alq 3.The results suggest that the interface state density at Sb 2 Se 3/Al interface is decreased by inserting an Alq 3 layer,and the charge recombination loss in the device is suppressed.This work provides a new electron transport material for Sb 2 Se 3 thin film solar cells.
文摘Background: Desmoplastic fibroblastoma (collagenous fibroma) is an uncommon benign soft-tissue tumor, rarely involving bone. It shares some overlapping features with other infiltrate tumors, such as desmoid-type fibromatosis, neurofibroma, and low-grade fibromyxoid sarcoma. The misdiagnosis may cause unnecessary surgical overtreatment, especially for those involving bone. In order to deepen the understanding of the diagnosis and differential diagnosis of desmoplastic fibroblastoma, we planned to analyze the clinical, radiological, and histopathological features and the outcome of desmoplastic fibroblastoma on the basis of case analysis and literature review. Methods: Sixteen cases were retrieved from the surgical pathology records from May 2011 to April 2016 in the Department of Pathology in Beijing Jishuitan Hospital. Formalin-fixed, paraffin-embedded specimens of 16 cases of desmoplastic fibroblastoma were collected. Hematoxylin and eosin stain and immunohistochemistry were used to observe the histological features of desmoplastic fibroblastoma of soft tissue and bone. The images for diagnosis obtained from the ultrasonic examination, X-ray, magnetic resonance imaging, and computed tomography were used to observe the radiological features. Related literatures were retrieved from the PubMed and CNKI databases. Results: Sixteen cases of desmoplastic fibroblastoma of soft tissue were located in the hand (n = 7), loot (n = 4), upper arm (n = 1), shoulder (n = 1), forearm (n = 2), and one case occurred in the proximal femur. Age ranged from 32 to 82 years (median age: 58 years). There were six females and ten males. Histologically, the lesions of soft tissue appeared as well-circumscribed masses with abundant collagenous matrix and low vascularity. Tumor cells were stellate- or spindle-shaped and uniformly distributed within the extracellular matrix. In five cases, the desmoplastic fibroblastoma were found to have infiltrated into the skeletal muscle tissue. In one case ofdesmoplastic fibroblastoma of bone, radiographs revealed osteolytically well-defined lesion, lmmunohistochemistry stain showed that vimentin and smooth muscle actin were positive in all cases of desmoplastic fibroblastoma. Conclusions: Desmoplastic fibroblastoma (collagenous fibroma) has prominent clinical, histopathological, and radiological features. Before the differential diagnosis from other tumors is obtained by thorough analysis and comparison of the similar and different characteristics, the appropriate surgical management and accurate prognosis evaluation could not be delivered to the patient.
文摘Background: Wide resection margins of osseous tumors are associated with a low incidence of local recurrence, making accurate measurement of the intraosseous extent of primary malignant long bone tumors is crucial. We compared the intraosseous tumor extent assessed by magnetic resonance imaging (MRI) with the gross specimen to evaluate the accuracy of MRI. Methods: A total of 255 patients with primary malignant tumors in the long bones were included. Using MRI, we defined the length of tumor as the distance from the articular surface to the boundary between abnormal and normal marrow signal. The extent of the abnormal intraosseous signal was measured on unenhanced T1-weighted (T1WI) magnetic resonance images after chemotherapy. All gross surgical specimens were sectioned, and tumor extent was measured. Wilcoxon signed-rank test was used to test the differences between MRI and gross specimen findings. Spearman's correlation analysis was used to test the correlation between groups. Results: Median tumor length by gross specimen (112 mm; range, 45–300 mm) was longer than that by MRI (108 mm; range, 45–304 mm;Z = -6.916, P 〈 0.001). Of 255 images, tumor length was accurately represented on 27 T1WI magnetic resonance images, overestimated on 79 images, and underestimated on 149 images. The median difference between imaging and gross specimen measurements was 2.0 mm (range: 1.0–15.0 mm) for the 79 cases where tumor length was overestimated, and 5.0 mm (range: 1.0–18.0 mm) for the 149 cases where tumor length was underestimated. The Spearman correlation demonstrated a high correlation of tumor length on gross specimen with the tumor length on MRI (R = 0.99, P 〈 0.01). Conclusions: We conclude that preoperative MRI could be a useful method in determining intramedullary malignant bone tumor boundaries and may serve as an accepted assessment method of long bone tumors before limb-sparing surgery.
基金Project supported by the National Natural Science Foundation of China (No. 51008017)the Fundamental Research Funds for the Central Universities of China (Nos. 2009JBM074 and 2009JBM075)
文摘Low frequency vibrations induced by underground railways have attracted increasing attention in recent years. To obtain the characteristics of low frequency vibrations and the low frequency performance of a floating slab track (FST), low frequency vibration tests on an FST in an underground laboratory at Beijing Jiaotong University were carried out. The FST and an unbalanced shaker SBZ30 for dynamic simulation were designed for use in low frequency vibration experiments. Vibration measurements were performed on the bogie of the unbalanced shaker, the rail, the slab, the tunnel invert, the tunnel wall, the tunnel apex, and on the ground surface at distances varying from 0 to 80 m from the track. Measurements were also made on several floors of an adjacent building. Detailed results of low frequency vibration tests were reported. The attenuation of low frequency vibrations with the distance from the track was presented, as well as the responses of different floors of the building. The experimental results could be regarded as a reference for developing methods to control low frequency vibrations and for adopting countermeasures.
基金financially supported by the Natural Science Foundation of Hainan Province (No. 521RC495)Key Research and Development Project of Hainan Province (Nos. ZDYF2020037 and ZDYF2020207)+2 种基金the National Natural Science Foundation of China (Nos. 6210031211 and 21805104)Innovative Research Projects for Graduate Students of Hainan Province (No. Hyb2020-05)the Start-Up Research Foundation of Hainan University (Nos. KYQD(ZR)-20008, 20082, 20083, 20084, 21065)
文摘Inexpensive,safe,and efficient conversion of solar energy to hydrogen from water splitting requires the development of effective and durable photocatalysts.Cu_(2)ZnSnS_(4)(CZTS),the emerging quaternary chalcogenide material for solar energy conversion,possesses many advantages,such as narrow direct band gap(1.5 eV),nontoxic,earth-abundance,and low melting point.Currently,CZTS-based photocatalysts have been extensively investigated for their application as an active photocatalyst in hydrogen evolution from water splitting,while the performance is still highly needed to be improved for the practical applications.In this review,first,the crystal and band structure properties of CZTS are briefly introduced,and afterward,the basic principle of photocatalytic hydrogen evolution from water splitting is discussed.Subsequently,the performance and status of bare CZTS,the combination of CZTS and co-catalysts,and CZTSbased heterojunction photocatalysts for hydrogen evolution are reviewed and discussed in detail.Finally,the issues and challenges currently encountered in the application of CZTS and their possible solutions for developing advanced CZTS photocatalysts are provided.
基金project supported by the National Natural Science Foundation of China(Nos.51278448 and 51478414)the National High-Tech R&D Program of China(863 Program)(Nos.2011AA060907 and 2012AA051502)the Specialized Research Fund for the Doctoral Program of Higher Education(No.20110101110018),China
文摘Synthetic mesh is often used in soft tissue reconstruction after artificial prosthesis replacement for patients with proximal humeral bone tumors.We carried out biomechanical and histological tests on two amputated extremities to test the stability of the joint and the biocompatibility of the synthetic meshes.
基金financially supported by the National Key Research and Development Program(No.2018YFA0702900)the National Natural Science Foundation of China(Nos.51774265 and 51701225)+3 种基金the National Science and Technology Major Project of China(Nos.2019ZX06004010 and 2017-VII008-0101)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDC04000000)the LingChuang Research Project of China National Nuclear Corporation Program of CAS Interdisciplinary Innovation TeamYouth Innovation Promotion Association,CAS。
文摘The interfacial oxidation behavior of Cr_(4)Mo_(4) V high-speed steel(HSS)joints undergoing hot-compression bonding was investigated by using optical microscopy(OM),scanning electron microscopy(SEM),and transmission electron microscopy(TEM).In the heating and holding processes,dispersed rod-like and granularδ-Al_(2)O_(3) oxides were formed at the interface and in the matrix near the interface due to the selective oxidation and internal oxidation of Al,while irregular Si-Al-O compounds and spheroidal SiO_(2) particles were formed at the interface.After the post-holding treatment,SiO_(2) oxides and Si-Al-O compounds were dissolved into the matrix,andδ-Al_(2)O_(3) oxides were transformed into nanoscaleα-Al_(2)O_(3) particles,which did not deteriorate the mechanical properties of the joints.The formation and migration of newly-formed grain boundaries by plastic deformation and post-holding treatment were the main mechanism for interface healing.The tensile test results showed that the strength of the healed joints was comparable to that of the base material,and the in-situ tensile observations proved that the fracture was initiated at the grain boundary of the matrix rather than at the interface.The clarification of interfacial oxides and microstructure is essential for the application of hot-compression bonding of HSSs.
基金This work was jointly supported by the grants from the National Natural Science Foundation of China(81372650 to Z Wang,81502028 to LX Yang and 81301821 to L Yu)Foundation of Shanghai Science and Technology Commission(grant number 13ZR1406900 to Z Wang)and The National Science and Technology Major Project(grant number 2018ZX10723204-004 to Z Wang).
文摘Background:The role of osteopontin(OPN)in intrahepatic cholangiocarcinoma(ICC)remains controversial.This study aimed to explore the prognostic value of OPN in patients with ICC undergoing curative resection.Methods:Patients undergoing curative resection from 2005 to 2016 were identified for inclusion in this retrospective study.The expression level of OPN in tumors was measured in each of the 228 patients by immunohistochemistry.Circulating OPN in serum was tested in 124 patients by ELISA.Tumor volume was calculated according to preoperative imaging or operation record.Proliferation assay,wound healing assay,and invasion assay were performed to investigate the biological function.Results:Low expression of OPN in tissue was associated with lymph node metastasis(P=0.009)and shorter overall survival(OS)(P=0.001).A low level of circulating OPN/volume was associated with multiple tumors(P<0.001),vascular invasion(P=0.027),visceral peritoneal perforation(P=0.001),and lymph node metastasis(P=0.002).It was also able to predict the invasive behavior,lymph node metastasis,and early recurrence with the area under the receiver operating curve(AUC)of being 0.719,0.708 and 0.622 respectively.Patients with a low level of circulating OPN/volume had shorter OS(P=0.028)and disease-free survival(DFS)(P=0.004)and could benefit from adjuvant chemotherapy(P=0.011).Compared with negative controlled cells,ICC cell lines,which expressed more OPN,showed a decelerated proliferation rate,the weaker ability of migration and invasion,while the opposite was true for the cells expressed less OPN.MMP1,MMP10,and CXCR4 were negatively regulated by OPN.Conclusions:A low level of circulating OPN/volume could indicate aggressive characteristics,along with poor prognosis and efficacy of adjuvant chemotherapy in ICC patients.Over expression of OPN may inhibit phenotypes facilitating ICC metastasis by negatively regulating MMP1,MMP10,and CXCR4.