In the construction of Three Gorges Project, the total amount of concrete is about 28 Mm\+3 , and the total amount of metal works and reinforcement is approximately 0.72 Mt . The TGP is constructed in 3 stages . The p...In the construction of Three Gorges Project, the total amount of concrete is about 28 Mm\+3 , and the total amount of metal works and reinforcement is approximately 0.72 Mt . The TGP is constructed in 3 stages . The preparation period together with the first stage is 5 years , the second stage and third stage are both 6 years .In the second stage construction of 6 years (1998～2003) , there are 18.46 Mm\+3 of concrete to be placed and 0.192 Mt of metal works and embedded parts for mechanical and electric equipment to be installed . In 1999, a world record of annual concrete placement of 4.585 Mm\+3 was set . In 2000, it is planned to place 5.4 Mm\+3 of concrete and to install 38 000 t of metal works . Construction equipments and layout of construction site , concrete production and its temperature control, metal works, mechanical and electric equipments in the second stage construction are presented.展开更多
Imaging plays an increasingly important role in the work up of prostate cancer(PCa) and magnetic resonance imaging(MRI) is generally accepted as the most accurate and promising imaging modality in the local staging of...Imaging plays an increasingly important role in the work up of prostate cancer(PCa) and magnetic resonance imaging(MRI) is generally accepted as the most accurate and promising imaging modality in the local staging of PCa due to its high spatial resolution and excellent soft tissue contrast. The quality and performance of MRI of the prostate has improved dramatically during the last decade. Mainly, the combination of morphological information and functional information on cell density, tissue perfusion or metabolism as provided in multi-parametric prostate MRI(mp MRI) has led to a substantial increase in lesion detection and characterization. The correlation between functional parameters as provided by MRI and the aggressiveness of PCa as determined by the Gleason Score may help in differentiating clinically signifi cant from indolent PCa non-invasively. Besides these pros, radiologists are confronted with an immense amount of information and standardized acquisition, interpretation and reporting of mp MRI is not yet a reality. Furthermore, prostate MRI availability is still limited to high volume centers in many countries; hence, it is not yet a routine tool in common daily practice. Hence, development of guidelines for standardized acquisition, interpretation andreporting of prostate MRI exams is urgently needed in order to provide useful information for treating clinicians. Preferably, multi-centric clinical studies comparing MRI fi ndings to step-section histological specimens are mandatory during the coming years. Furthermore, simplification of the acquisition must be achieved in order to make this imaging modality applicable for daily use in common uro-radiological practice.展开更多
文摘In the construction of Three Gorges Project, the total amount of concrete is about 28 Mm\+3 , and the total amount of metal works and reinforcement is approximately 0.72 Mt . The TGP is constructed in 3 stages . The preparation period together with the first stage is 5 years , the second stage and third stage are both 6 years .In the second stage construction of 6 years (1998～2003) , there are 18.46 Mm\+3 of concrete to be placed and 0.192 Mt of metal works and embedded parts for mechanical and electric equipment to be installed . In 1999, a world record of annual concrete placement of 4.585 Mm\+3 was set . In 2000, it is planned to place 5.4 Mm\+3 of concrete and to install 38 000 t of metal works . Construction equipments and layout of construction site , concrete production and its temperature control, metal works, mechanical and electric equipments in the second stage construction are presented.
文摘Imaging plays an increasingly important role in the work up of prostate cancer(PCa) and magnetic resonance imaging(MRI) is generally accepted as the most accurate and promising imaging modality in the local staging of PCa due to its high spatial resolution and excellent soft tissue contrast. The quality and performance of MRI of the prostate has improved dramatically during the last decade. Mainly, the combination of morphological information and functional information on cell density, tissue perfusion or metabolism as provided in multi-parametric prostate MRI(mp MRI) has led to a substantial increase in lesion detection and characterization. The correlation between functional parameters as provided by MRI and the aggressiveness of PCa as determined by the Gleason Score may help in differentiating clinically signifi cant from indolent PCa non-invasively. Besides these pros, radiologists are confronted with an immense amount of information and standardized acquisition, interpretation and reporting of mp MRI is not yet a reality. Furthermore, prostate MRI availability is still limited to high volume centers in many countries; hence, it is not yet a routine tool in common daily practice. Hence, development of guidelines for standardized acquisition, interpretation andreporting of prostate MRI exams is urgently needed in order to provide useful information for treating clinicians. Preferably, multi-centric clinical studies comparing MRI fi ndings to step-section histological specimens are mandatory during the coming years. Furthermore, simplification of the acquisition must be achieved in order to make this imaging modality applicable for daily use in common uro-radiological practice.
