Application perspectives of polyhydroxyalkanoates / 生物工程学报

Polyhydroxyalkanoates are polyesters of hydroxyalkanoates synthesized by many bacteria and haloarchaea as carbon and energy storage materials. There are more than 150 types of polyhydroxyalkanoate monomers reported, resulting in a variety of Polyhydroxyalkanoates with diverse properties. The material variability, nonlinear optical properties, piezoelectric properties, gas barrier properties, thermoplasticity, biodegradability, and biocompatibility allow polyhydroxyalkanoates to be used for plastic packaging, chiral chemicals generation, medicine, agriculture and bio-energy fields. This review introduces the current applications and future development of polyhydroxyalkanoates.

Effect of the width of excisional mucosa stoma ring on postoperative results of procedure for prolapse and hemorrhoids method / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To explore the effect of the width of excisional mucosal stoma ring on postoperative results of procedure for prolapse and hemorrhoids (PPH) in the treatment of hemorrhoids.</p><p><b>METHODS</b>Four hundred and eighty hemorrhoid patients were treated with circular stapler. Whether excisional mucosa stoma ring was regular or not, and its width were recorded. After follow-up from one month to 24 months,the outcomes were compared.</p><p><b>RESULTS</b>The mean age of the patients was (46.6+/- 5.1) years. Regular mucosa stoma ring was excited in 303 cases,while irregular ring in 177 cases. Hemorrhoids prolapse occurred in 18 cases of the patients with irregular mucosal ring excited, while only 8 cases of the patients with regular ring excited (P< 0.01). There was significant difference in the incidence of hemorrhoids prolapse between the different groups according to different width of excisional mucosal stoma ring (P< 0.01), and the patients with postoperative hemorrhoids prolapse was lest with the width of excisional mucosal stoma ring more than 3 cm.</p><p><b>CONCLUSIONS</b>The width of excisional mucosal stoma ring is one of the effecting factors of surgical outcomes. It is effective to excite mucosal stoma ring more than 2 cm,and most effective to excite mucosal stoma ring more than 3 cm.</p>

Analysis of the relationship between stoma position and postoperative effects of procedure for prolapse and hemorrhoids in the treatment of hemorrhoids / 中华外科杂志

<p><b>OBJECTIVE</b>To explore the relationship between stoma position and postoperative effects of procedure for prolapse and hemorrhoids (PPH) in the treatment of hemorrhoids.</p><p><b>METHODS</b>Four hundred and one hemorrhoid patients were treated with circular stapler. II hemorrhoids, 45 cases; III-IV hemorrhoids, 356 cases. The position of stoma located 1 cm up dentate line, 219 cases; 1-2 cm up dentate line, 87 cases; 2-3 cm up dentate line, 60 cases; 3-4 cm up dentate line, 25 cases; > 4 cm up dentate line, 10 cases. The patients were followed from one week to two years postoperatively.</p><p><b>RESULTS</b>Postoperative effects and procidentia rates have significant association with the position of stoma. If the distance between position of stoma and dentate line is < or = 2 cm, the postoperative procidentia rate was 1.1%, lower than that of the distance > or = 4 cm.</p><p><b>CONCLUSIONS</b>The complication and procidentia rate of PPH is associated with the stoma position. The stoma position should be no more than 2 cm to dentate line.</p>