RESUMEN
BACKGROUND: There are few reports of overall strength of laparoscopic and open incisional hernia repair. METHODS: After anesthesia, a 2-inch circular defect was made in the abdominal wall of 28 female swine. Gore-Tex DualMesh Biomaterial (W. L. Gore & Associates, Flagstaff, AZ) was used for all repairs. Sixteen animals underwent open repair and 12 underwent laparoscopic repair. Burst strength was detected within 2 weeks and at 6 weeks by euthanizing the animals and insufflating the abdominal cavity with water while measuring the intraabdominal pressure until it could no longer be pressurized. RESULTS: Three events occurred after insufflation: rupture around patch (R), dissection from insufflation or pressure monitoring sites (D), or rectal prolapse (P). Failure after open early repair occurred at 289 (range 219-388) mmHg with 7-R, 1-P and late 289 (196-343) mmHg with 1-R, 6-P. Failure after laparoscopic early repair occurred at 259 (191-388) mmHg with 4-R, 1-P, 1-D and late 291 (140-330) mmHg with 2-R, 1-P, 3-D. Late groups were less likely to rupture. CONCLUSION: Both hernia repairs are durable at early and late periods. Tissue ingrowth adds to repair strength. We could not show that one repair was stronger than the other. Nonetheless, laparoscopic repair tended to degrade by dissection, which was our highest pressure event.
Asunto(s)
Pared Abdominal/cirugía , Herniorrafia , Laparoscopía/métodos , Laparotomía/métodos , Pared Abdominal/patología , Animales , Fascia/patología , Fasciotomía , Femenino , Insuflación , Modelos Animales , Estrés Mecánico , Mallas Quirúrgicas , Porcinos , Resistencia a la TracciónRESUMEN
Reliable communication on the Internet is guaranteed by a standard set of protocols, used by all computers. Here we show that these protocols can be exploited to compute with the communication infrastructure, transforming the Internet into a distributed computer in which servers unwittingly perform computation on behalf of a remote node. In this model, which we call 'parasitic computing', one machine forces target computers to solve a piece of a complex computational problem merely by engaging them in standard communication. Consequently, the target computers are unaware that they have performed computation for the benefit of a commanding node. As experimental evidence of the principle of parasitic computing, we harness the power of several web servers across the globe, which-unknown to them-work together to solve an NP complete problem.
