AIM To recognize the characteristic findings of micrQliver cancer (MLC) and to evaluate the effect of CT arterial portography (CTAP) and CT hepatic arteriography (CTHA) in diagnosis of MLC. METHODS Between April 1996 ...AIM To recognize the characteristic findings of micrQliver cancer (MLC) and to evaluate the effect of CT arterial portography (CTAP) and CT hepatic arteriography (CTHA) in diagnosis of MLC. METHODS Between April 1996 to December 1998, CTAP and CTHA were performed in 12patients with MLC, which were not detect ed byconventional CT examinations. After CTHA, 3 mL-- 5 mL mixture of lipiodol, doxorubic in andmitomycin C were injected into hepatic arterythrough the catheter, and then followed up by CTthree or four weeks later (Lipiodol CT LP-CT).RESULTS A total of 22 micro--tumors (0 .2 cm 0.6 cm in diameter ) were detected in 12patients, which manifested as small perfusiondefects in CTAP and small round enhancement inCTHA. The rate of detectability of CTAP andCTHA was 68.2% (15/ 22) and 77.3% (17/ 22)respectively, and the rate of the simultaneoususe of both procedures reached 86. 4% (19/ 22 ).All micro--tumors were demonstrated as punctatelipiodol deposit fool in LP--CT. After LP--CT, theelevated serum level of Q-fetoprotein (AFP)dropped to the normal level in all patients.CONCLUSION The CTAP and CTHA are the mostsensitive imaging methods for detecting microIiver cancer. Confirmed by the change of theelevated serum AFP level and lipiodol depositfool in LP-CT, small perfusion defects in CTAPand punctate enhancement in CTHA may suggestmicro--liver cancer.展开更多
Spine-related disorders are caused by several factors including (1) spinal nerve/visceral nerve stimulation by perivertebral aseptic inflammation, (2) spinal nerve/visceral nerve compression by injured periverterb...Spine-related disorders are caused by several factors including (1) spinal nerve/visceral nerve stimulation by perivertebral aseptic inflammation, (2) spinal nerve/visceral nerve compression by injured periverterbal soft tissue, dislocated perivertebral small joint, and proliferative/degenerative tissue and, (3) secondary damage to the spinal cord, peripheral nerve, vessels and autonomic nerve, which further stimulate nerve root sheath and surround- ing pain-carrying nerve fibers. In many cases, the source of pain cannot be detected by standard image modalities. Particularly in anatomically complex regions like the spine, SPECT/CT can be helpful for some aspects by intro- ducing a metabolical dimension to the classical way of morphology-based diagnostic. The aim of the present review was to give an overview of the adoption of SPECT/CT in a clinical spine-focused setting.展开更多
The evolution of stresses due to inhomogeneity in metal injection molding (MIM) parts during sintering was investigated. The sintering model of porous materials during densification process was developed based on th...The evolution of stresses due to inhomogeneity in metal injection molding (MIM) parts during sintering was investigated. The sintering model of porous materials during densification process was developed based on the continuum mechanics and thermal elasto-viseoplastic constitutive law. Model parameters were identified from the dilatometer sintering experiment. The real density distribution of green body was measured by X-ray computed tomography (CT), which was regarded as the initial condition of sintering model. Numerical calculation of the above sintering model was carried out with the finite element soRware Abaqus, through the user-defined material mechanical behavior (UMAT). The calculation results showed that shrinkages of low density regions were faster than those of high density regions during sintering, which led to internal stresses. Compressive stresses existed in high density regions and tensile stresses existed in low density regions. The densification of local regions depended on not only the initial density, but also the evolution of stresses during the sintering stage.展开更多
基金Supported by“9.5”National Major Project of National Cammittee of Sciences and Technology,No.96-907-03-02.
文摘AIM To recognize the characteristic findings of micrQliver cancer (MLC) and to evaluate the effect of CT arterial portography (CTAP) and CT hepatic arteriography (CTHA) in diagnosis of MLC. METHODS Between April 1996 to December 1998, CTAP and CTHA were performed in 12patients with MLC, which were not detect ed byconventional CT examinations. After CTHA, 3 mL-- 5 mL mixture of lipiodol, doxorubic in andmitomycin C were injected into hepatic arterythrough the catheter, and then followed up by CTthree or four weeks later (Lipiodol CT LP-CT).RESULTS A total of 22 micro--tumors (0 .2 cm 0.6 cm in diameter ) were detected in 12patients, which manifested as small perfusiondefects in CTAP and small round enhancement inCTHA. The rate of detectability of CTAP andCTHA was 68.2% (15/ 22) and 77.3% (17/ 22)respectively, and the rate of the simultaneoususe of both procedures reached 86. 4% (19/ 22 ).All micro--tumors were demonstrated as punctatelipiodol deposit fool in LP--CT. After LP--CT, theelevated serum level of Q-fetoprotein (AFP)dropped to the normal level in all patients.CONCLUSION The CTAP and CTHA are the mostsensitive imaging methods for detecting microIiver cancer. Confirmed by the change of theelevated serum AFP level and lipiodol depositfool in LP-CT, small perfusion defects in CTAPand punctate enhancement in CTHA may suggestmicro--liver cancer.
文摘Spine-related disorders are caused by several factors including (1) spinal nerve/visceral nerve stimulation by perivertebral aseptic inflammation, (2) spinal nerve/visceral nerve compression by injured periverterbal soft tissue, dislocated perivertebral small joint, and proliferative/degenerative tissue and, (3) secondary damage to the spinal cord, peripheral nerve, vessels and autonomic nerve, which further stimulate nerve root sheath and surround- ing pain-carrying nerve fibers. In many cases, the source of pain cannot be detected by standard image modalities. Particularly in anatomically complex regions like the spine, SPECT/CT can be helpful for some aspects by intro- ducing a metabolical dimension to the classical way of morphology-based diagnostic. The aim of the present review was to give an overview of the adoption of SPECT/CT in a clinical spine-focused setting.
基金Project(2011CB606306)supported by the National Basic Research Program of ChinaProject(FRF-TP-10-003B)supported by the Fundamental Research Funds for the Central Universities,ChinaProject(51274040)supported by the National Natural Science Foundation of China
文摘The evolution of stresses due to inhomogeneity in metal injection molding (MIM) parts during sintering was investigated. The sintering model of porous materials during densification process was developed based on the continuum mechanics and thermal elasto-viseoplastic constitutive law. Model parameters were identified from the dilatometer sintering experiment. The real density distribution of green body was measured by X-ray computed tomography (CT), which was regarded as the initial condition of sintering model. Numerical calculation of the above sintering model was carried out with the finite element soRware Abaqus, through the user-defined material mechanical behavior (UMAT). The calculation results showed that shrinkages of low density regions were faster than those of high density regions during sintering, which led to internal stresses. Compressive stresses existed in high density regions and tensile stresses existed in low density regions. The densification of local regions depended on not only the initial density, but also the evolution of stresses during the sintering stage.