ObjectiveTo discuss the influence on diagn osing of femoral vein reflux by using the different ultrasound Doppler probing points. MethodsUsing pulse wave(PW) and color Doppler flow imaging, 134 femoral veins in 67 cases of lower limb varicosity were detected at 3 different probing points to check up the deep venous reflux after Valsava maneuver. The ultrasonographic data were compared with the results of venous DSA and operation to analyze the influence on diagnosis. ResultsThe reflux data obtained from the upper point of superficial femoral vein was most correlative with the results of DSA and operation. ConclusionsThe PW is a satisfactory technique in diagnosing the femoral reflux, and the upper point of superficial femoral vein is a most reasonable probing point.

Nitrogen is one of the most important nutrient elements for plants and a major limiting factor in plant growth and crop productivity. Glutamine synthase (GS) is a key enzyme involved in the nitrogen assimilation and recycling in plants. So far, members of the glutamine synthase gene family have been characterized in many plants such as Arabidopsis, rice, wheat, and maize. Reports show that GS are involved in the growth and development of plants, in particular its role in seed production. However, the outcome has generally been inconsistent, which are probably derived from the transcriptional and post-translational regulation of GS genes. In this review, we outlined studies on GS gene classification, QTL mapping, the relationship between GS genes and plant growth with nitrogen and the distribution characters, the biological functions of GS genes, as well as expression control at different regulation levels. In addition, we summarized the application prospects of glutamine synthetase genes in enhancing plant growth and yield by improving the nitrogen use efficiency. The prospects were presented on the improvement of nitrogen utility efficiency in crops and plant nitrogen status diagnosis on the basis of glutamine synthase gene regulation.
Arabidopsis ; Genes, Plant ; Glutamate-Ammonia Ligase ; genetics ; Nitrogen ; metabolism ; Oryza ; Plants ; enzymology ; genetics ; Triticum ; Zea mays