RESUMEN

As a traditional animal drug, Hirudo is slightly toxic and has the effects of breaking blood stasis, dredging meridians, expelling stasis, and resolving mass. It has a long history of processing, and the early boiling records can be traced back to the Han Dynasty. More than ten processing methods such as frying, roasting, and lime processing appeared later. After processing, Hirudo is deodorized and modified in taste and becomes crispy, which is conducive to crushing and clinical application. At present, the reported components in Hirudo mainly include protein polypeptides, pteridines, and lipids, which have anti-coagulant, anti-thrombotic, anti-atherosclerotic, anti-tumor, and other pharmacological effects. This study reviewed the processing history evolution, chemical consti-tuents, and pharmacological effects of Hirudo to provide a reference for the related research on Hirudo.

Asunto(s)

Medicamentos Herbarios Chinos , Sanguijuelas , Trombosis , Animales , Medicamentos Herbarios Chinos/farmacología , Evolución Química , Restricción Física

RESUMEN

A 'model' material of recycled polypropylene (PP) was prepared through the injection molding process, and the effect of processing history on the polymer characteristics was investigated through the high-speed melt spinning of virgin and recycled PP. On-line measurement of the thinning behavior of the spin-line revealed the downstream shift of solidification point for the recycled PP at the take-up velocity of 1.0 km/min, indicating the suppression of flow-induced crystallization. The difference was not clear at higher take-up velocities of up to 5 km/min. For any identical take-up velocity, no clear difference in the stress-strain curves and birefringence of the fibers from virgin and recycled PP could be observed, whereas the detailed investigation on the variation of relative amount of c-axis and a*-axis oriented crystals in the fibers prepared at varied take-up velocities suggested the deterioration of flow-induced crystallization at 1.0 km/min. It was speculated that the processing history induced the lowering of the entanglement density, which affected the melt spinning and crystallization behavior. An undistinguishable difference between the virgin and recycled PP at increased take-up velocities suggested the existence of an optimum elongational strain rate for the detection of the different states of molecular entanglement.