AIM： To investigate the damaging effect of high-intensity focused ultrasound （HIFU） on cancer cells and the inhibitory effect on tumor growth. METHODS： Hurine H22 hepatic cancer cells were treated with HIFU at the...AIM： To investigate the damaging effect of high-intensity focused ultrasound （HIFU） on cancer cells and the inhibitory effect on tumor growth. METHODS： Hurine H22 hepatic cancer cells were treated with HIFU at the same intensity for different lengths of time and at different intensities for the same length oftime in vitro, the dead cancer cells were determined by trypan blue staining. Two groups of cancer cells treated with HIFU at the lowest and highest intensity were inoculated into mice. Tumor masses were removed and weighed after 2 wk, tumor growth in each group was confirmed pathologically.RESULTS： The death rate of cancer cells treated with HIFU at 1 000 W/cm^2 for 0.5, 1, 2, 4, 8, and 12 s was 3.11±1.21%, 13.37±2.56%, 38.84±3.68%, 47.22±5.76%,87.55±7.32%, and 94.33±8.11%, respectively. A positive relationship between the death rates of cancer cells and the length of HIFU treatment time was found （r = 0.96,P〈0.01）. The death rate of cancer cells treated with HIFU at the intensity of 100, 200, 400, 600, 800, and 1 000 W/cm^2 for 8 s was 26.31±3.26%, 31.00±3.87%, 41.97±5.86%,72.23±8.12%, 94.90±8.67%, and 99.30±9.18%, respectively. A positive relationship between the death rates of cancer cells and the intensities of HIFU treatment was confirmed （r= 0.98, P〈0.01）. The cancer cells treated with HIFU at 1 000 W/cm^2 for 8 s were inoculated intomice ed into. The tumor inhibitory rate was 90.35% compared to the control （P〈0.01）. In the experimental group inoculated with the cancer cells treated with HIFU at 1 000 W/cm^2 for 0.5 s, the tumor inhibitory rate was 22.9% （P〈0.01）. By pathological examination, tumor growth was confirmed in 8 out of 14 mice （57.14%, 8/14） inoculated with the cancer cells treated with HIFU at 1 000 W/cm^2 for 8 s, which was significantly lower than that in the control （100%, 15/15, P〈O.05）.CONCLUSION： HIFU is effective on killing or damage of H22 hepatic cancer cells in vitro and on inhibiting tumor growth in mice ex vivo.展开更多
Aiming at accuracy control of the thermal crown of work rolls in cold rolling,new parameters such as regulation domain and control-efficiency factors were proposed and a numerical analysis model of the thermal crown o...Aiming at accuracy control of the thermal crown of work rolls in cold rolling,new parameters such as regulation domain and control-efficiency factors were proposed and a numerical analysis model of the thermal crown of work rolls was established using finite difference method to study roll's thermal deformation.Based on simulation results,the influences of control-efficiency factors on thermal crown are presented and the thermal crown of work rolls is analyzed after taking sub-cooling of sprinkling beam into consideration.It has been found that the control-efficiency factor of any position on the roll's surface is linear function of the temperature and the control ability of water temperature is stronger than other control parameters.In addition,the verification of the model has been carried out based on the producing technology data in some factories and the numerical simulation results coincide well with the experimental data.Therefore,this work has important value for on-line control of roll's crown in cold rolling.展开更多
To reveal the water inrush mechanics of underground deep rock mass subjected to dynamic disturbance such as blasting, compression-shear rock crack initiation rule and the evolution of crack tip stress intensity factor...To reveal the water inrush mechanics of underground deep rock mass subjected to dynamic disturbance such as blasting, compression-shear rock crack initiation rule and the evolution of crack tip stress intensity factor are analyzed under static-dynamic loading and seepage water pressure on the basis of theoretical deduction and experimental research. It is shown that the major influence factors of the crack tip stress intensity factor are seepage pressure, dynamic load, static stress and crack angle. The existence of seepage water pressure aggravates propagation of branch cracks. With the seepage pressure increasing, the branch crack experiences unstable extension from stable propagation. The dynamic load in the direction of maximum main stress increases type I crack tip stress intensity factor and its influence on type II crack intensity factor is related with crack angle and material property. Crack initiation angle changes with the dynamic load. The initial crack initiation angle of type I dynamic crack fracture is 70.5°. The compression-shear crack initial strength is related to seepage pressure, confining pressure, and dynamic load. Experimental results verify that the initial crack strength increases with the confining pressure increasing, and decreases with the seepage pressure increasing.展开更多
This paper systematically generalizes relevant theories and methods regarding mining cost control and constitutes the model for the mining cost analysis. It also comes up with the sensitivity factor analysis to conduc...This paper systematically generalizes relevant theories and methods regarding mining cost control and constitutes the model for the mining cost analysis. It also comes up with the sensitivity factor analysis to conduct mining cost control. The theories and methods have been experimented with Jiangsu Chuanshan Mining Joint-Stock Company Ltd. Case studies have been undertaken on mining cost of the company and the most sensitive factor which affects mining cost has been found accordingly. Finally the paper concludes that the focus concerning the cost control of the company should be directed at output and material costs.展开更多
The high cycle fatigue response of a high V-alloyed powder metallurgy tool steel （AISI 11） with different inclusion sizes was studied. Two materials of this grade at a similar hardness of about HRC 60 were subjected...The high cycle fatigue response of a high V-alloyed powder metallurgy tool steel （AISI 11） with different inclusion sizes was studied. Two materials of this grade at a similar hardness of about HRC 60 were subjected to axial loading fatigue tests, tensile tests and fracture toughness measurements to investigate their mechanical properties. Large inclusion above 70 ~rn is indicated to be responsible for the tensile fracture which happens before yielding. The fatigue strength obtained up to 107 cycles is found to decrease from approximately 1 538 MPa to 1000 MPa with the inclusion size increasing above 30 Izm. The internally induced crack initiation is mainly attributed to the surface compressive residual stress of 300-450 MPa. Fractographic evaluation demonstrates that the crack initiation and propagation controlling factors of the two materials are almost the same, indicating that the two factors would be insignificantly affected by the inclusion size level. Paris sizes of the two materials both show a tendency to decrease as the ratio of stress intensity factor of crack origin to factor of fish-eye increases. The investigation into the relationship between stress intensity factors and fatigue life of the two materials further indicates that the high cycle fatigue behavior of AISI 11 is controlled by crack propagation.展开更多
Objective： The aim of this study was to compare effect of rh-endostatin on microvasculature in tumor and myocardium tissue. Methods： Nude mice were randomized into 4 groups, blank control group [did not burden tumor...Objective： The aim of this study was to compare effect of rh-endostatin on microvasculature in tumor and myocardium tissue. Methods： Nude mice were randomized into 4 groups, blank control group [did not burden tumor, normalsaline （NS） 100 μL/d], drug control group （did not burden tumor, rh-endostatin 400 μg/d）, model group （mice burdened tumor, NS 100 μL/d） and treatment group （mice burdened tumor, rh-endostatin 400 μg/d）, administration was given during d1-d28. The volume of tumor and the weight of mouse were measured before and after administration. The expression of CD34, MMP-2, MMP-9, HIF-la and VEGF in myocardium and tumor were detected by immunohistochemistry. The structure of vasculature was observed by immunoenzymatic double staining with CD34 and Masson. Results： The tumor volume increase of treatment group （48.18 mm3） was less than the model group （113.80 mm3）, the change of weight was not significant among the four groups. After treated with endotar, the expression of MMP-9 and VEGF in tumor were obviously down-regulated, but the same results was not found in MMP-2, HIF-la of tumor. MVD in tumor of treatment group decreased significantly compared with model group. Proportion of tumor vessels covered by collagen in treatment group increased compared with model group. However, MVD and microvasculature in myocardium did not change significantly. Conclusion： Rh-endostatin can decrease the expression of MMP-9, VEGF and MVD to inhibit growth of tumor and normalize micrangium in tumor but cannot weaken MMPs and MVD of mature micrangium in myocardium.展开更多
Most E26 transformation-specific （ETS） transcription factors are involved in the pathogenesis and progression of cancer. This is in part due to the roles of ETS transcription factors in basic biological processes su...Most E26 transformation-specific （ETS） transcription factors are involved in the pathogenesis and progression of cancer. This is in part due to the roles of ETS transcription factors in basic biological processes such as growth, proliferation, and differentiation, and also because of their regulatory functions that have physiological relevance in tumorigenesis, immunity, and basal cellular homoeostasis. A member of the E74-1ike factor （ELF） subfamily of the ETS transcription factor family--myeloid elf-l-Uke factor （MEF）, designated as ELF4~has been shown to be critically involved in immune response and signalling, osteogenesis, adipo- genesis, cancer, and stem cell quiescence. ELF4 carries out these functions as a transcriptional activator or through interactions with its partner proteins. Mutations in ELF4 cause aberrant interactions and induce downstream processes that may lead to dis- eased cells. Knowing how ELF4 impinges on certain cellular processes and how it is regulated in the cells can lead to a better understanding of the physiological and pathological consequences of modulated ELF4 activity.展开更多
基金Supported by the Grant from National Economic Trade Committee, No. 2000-312-2
文摘AIM： To investigate the damaging effect of high-intensity focused ultrasound （HIFU） on cancer cells and the inhibitory effect on tumor growth. METHODS： Hurine H22 hepatic cancer cells were treated with HIFU at the same intensity for different lengths of time and at different intensities for the same length oftime in vitro, the dead cancer cells were determined by trypan blue staining. Two groups of cancer cells treated with HIFU at the lowest and highest intensity were inoculated into mice. Tumor masses were removed and weighed after 2 wk, tumor growth in each group was confirmed pathologically.RESULTS： The death rate of cancer cells treated with HIFU at 1 000 W/cm^2 for 0.5, 1, 2, 4, 8, and 12 s was 3.11±1.21%, 13.37±2.56%, 38.84±3.68%, 47.22±5.76%,87.55±7.32%, and 94.33±8.11%, respectively. A positive relationship between the death rates of cancer cells and the length of HIFU treatment time was found （r = 0.96,P〈0.01）. The death rate of cancer cells treated with HIFU at the intensity of 100, 200, 400, 600, 800, and 1 000 W/cm^2 for 8 s was 26.31±3.26%, 31.00±3.87%, 41.97±5.86%,72.23±8.12%, 94.90±8.67%, and 99.30±9.18%, respectively. A positive relationship between the death rates of cancer cells and the intensities of HIFU treatment was confirmed （r= 0.98, P〈0.01）. The cancer cells treated with HIFU at 1 000 W/cm^2 for 8 s were inoculated intomice ed into. The tumor inhibitory rate was 90.35% compared to the control （P〈0.01）. In the experimental group inoculated with the cancer cells treated with HIFU at 1 000 W/cm^2 for 0.5 s, the tumor inhibitory rate was 22.9% （P〈0.01）. By pathological examination, tumor growth was confirmed in 8 out of 14 mice （57.14%, 8/14） inoculated with the cancer cells treated with HIFU at 1 000 W/cm^2 for 8 s, which was significantly lower than that in the control （100%, 15/15, P〈O.05）.CONCLUSION： HIFU is effective on killing or damage of H22 hepatic cancer cells in vitro and on inhibiting tumor growth in mice ex vivo.
基金Project(2007BAF02B12)supported by the National Science Technology Support Program of ChinaProjects(E2011203090,E2012203028)supported by the Natural Science Foundation of Hebei Province,China
文摘Aiming at accuracy control of the thermal crown of work rolls in cold rolling,new parameters such as regulation domain and control-efficiency factors were proposed and a numerical analysis model of the thermal crown of work rolls was established using finite difference method to study roll's thermal deformation.Based on simulation results,the influences of control-efficiency factors on thermal crown are presented and the thermal crown of work rolls is analyzed after taking sub-cooling of sprinkling beam into consideration.It has been found that the control-efficiency factor of any position on the roll's surface is linear function of the temperature and the control ability of water temperature is stronger than other control parameters.In addition,the verification of the model has been carried out based on the producing technology data in some factories and the numerical simulation results coincide well with the experimental data.Therefore,this work has important value for on-line control of roll's crown in cold rolling.
基金Projects(51174228,51174088,51204068,51274097)supported by the National Natural Science Foundation of China
文摘To reveal the water inrush mechanics of underground deep rock mass subjected to dynamic disturbance such as blasting, compression-shear rock crack initiation rule and the evolution of crack tip stress intensity factor are analyzed under static-dynamic loading and seepage water pressure on the basis of theoretical deduction and experimental research. It is shown that the major influence factors of the crack tip stress intensity factor are seepage pressure, dynamic load, static stress and crack angle. The existence of seepage water pressure aggravates propagation of branch cracks. With the seepage pressure increasing, the branch crack experiences unstable extension from stable propagation. The dynamic load in the direction of maximum main stress increases type I crack tip stress intensity factor and its influence on type II crack intensity factor is related with crack angle and material property. Crack initiation angle changes with the dynamic load. The initial crack initiation angle of type I dynamic crack fracture is 70.5°. The compression-shear crack initial strength is related to seepage pressure, confining pressure, and dynamic load. Experimental results verify that the initial crack strength increases with the confining pressure increasing, and decreases with the seepage pressure increasing.
文摘This paper systematically generalizes relevant theories and methods regarding mining cost control and constitutes the model for the mining cost analysis. It also comes up with the sensitivity factor analysis to conduct mining cost control. The theories and methods have been experimented with Jiangsu Chuanshan Mining Joint-Stock Company Ltd. Case studies have been undertaken on mining cost of the company and the most sensitive factor which affects mining cost has been found accordingly. Finally the paper concludes that the focus concerning the cost control of the company should be directed at output and material costs.
基金Project(2007BAE51B05)supported by the National Key Technologies Research and Development Program of China
文摘The high cycle fatigue response of a high V-alloyed powder metallurgy tool steel （AISI 11） with different inclusion sizes was studied. Two materials of this grade at a similar hardness of about HRC 60 were subjected to axial loading fatigue tests, tensile tests and fracture toughness measurements to investigate their mechanical properties. Large inclusion above 70 ~rn is indicated to be responsible for the tensile fracture which happens before yielding. The fatigue strength obtained up to 107 cycles is found to decrease from approximately 1 538 MPa to 1000 MPa with the inclusion size increasing above 30 Izm. The internally induced crack initiation is mainly attributed to the surface compressive residual stress of 300-450 MPa. Fractographic evaluation demonstrates that the crack initiation and propagation controlling factors of the two materials are almost the same, indicating that the two factors would be insignificantly affected by the inclusion size level. Paris sizes of the two materials both show a tendency to decrease as the ratio of stress intensity factor of crack origin to factor of fish-eye increases. The investigation into the relationship between stress intensity factors and fatigue life of the two materials further indicates that the high cycle fatigue behavior of AISI 11 is controlled by crack propagation.
基金Supported by grants from the Tianjin Medical University Research Projects(2009KY37)CSCO Vascular Target Fund Research Projects of Roche(Y-X2011-001)
文摘Objective： The aim of this study was to compare effect of rh-endostatin on microvasculature in tumor and myocardium tissue. Methods： Nude mice were randomized into 4 groups, blank control group [did not burden tumor, normalsaline （NS） 100 μL/d], drug control group （did not burden tumor, rh-endostatin 400 μg/d）, model group （mice burdened tumor, NS 100 μL/d） and treatment group （mice burdened tumor, rh-endostatin 400 μg/d）, administration was given during d1-d28. The volume of tumor and the weight of mouse were measured before and after administration. The expression of CD34, MMP-2, MMP-9, HIF-la and VEGF in myocardium and tumor were detected by immunohistochemistry. The structure of vasculature was observed by immunoenzymatic double staining with CD34 and Masson. Results： The tumor volume increase of treatment group （48.18 mm3） was less than the model group （113.80 mm3）, the change of weight was not significant among the four groups. After treated with endotar, the expression of MMP-9 and VEGF in tumor were obviously down-regulated, but the same results was not found in MMP-2, HIF-la of tumor. MVD in tumor of treatment group decreased significantly compared with model group. Proportion of tumor vessels covered by collagen in treatment group increased compared with model group. However, MVD and microvasculature in myocardium did not change significantly. Conclusion： Rh-endostatin can decrease the expression of MMP-9, VEGF and MVD to inhibit growth of tumor and normalize micrangium in tumor but cannot weaken MMPs and MVD of mature micrangium in myocardium.
文摘Most E26 transformation-specific （ETS） transcription factors are involved in the pathogenesis and progression of cancer. This is in part due to the roles of ETS transcription factors in basic biological processes such as growth, proliferation, and differentiation, and also because of their regulatory functions that have physiological relevance in tumorigenesis, immunity, and basal cellular homoeostasis. A member of the E74-1ike factor （ELF） subfamily of the ETS transcription factor family--myeloid elf-l-Uke factor （MEF）, designated as ELF4~has been shown to be critically involved in immune response and signalling, osteogenesis, adipo- genesis, cancer, and stem cell quiescence. ELF4 carries out these functions as a transcriptional activator or through interactions with its partner proteins. Mutations in ELF4 cause aberrant interactions and induce downstream processes that may lead to dis- eased cells. Knowing how ELF4 impinges on certain cellular processes and how it is regulated in the cells can lead to a better understanding of the physiological and pathological consequences of modulated ELF4 activity.
