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Background Minimally invasive radio-guided parathyroidectomy (MIRP) has been embraced as an acceptable therapeutic approach to primary hyperparathyroidism. Preoperative sestamibi scanning has facilitated this technique. Here we evaluate the addition of a rapid intraoperative parathyroid hormone (iPTH) assay for patients undergoing MIRP. Methods A series of 51 patients underwent sestamibi localization of parathyroid glands followed by MIRP for primary hyperparathyroidism. Using peripheral venous samples, iPTH levels were measured prior to gland excision, as well as post-excision at 5, 10, and 15 minutes, taking a 50% reduction in iPTH level as indicative of complete excision. Next, changes in serum iPTH were compared with preoperative and postoperative changes in serum calcium, as well as levels of intraoperative ex-vivo radiation counts taken by hand-held gamma probe. Results In this series, a drop of greater than 50% in iPTH levels was observed in 94% of patients (n = 48). Moreover, a significant drop in iPTH occurred within 10 minutes of excision in the majority (n = 42) of cases (P < 0.004). Changes in iPTH were comparable with the therapeutic reduction in calcium levels, as well as with the change in intraoperative ex-vivo gamma counts. Conclusions This study demonstrates that the addition of an iPTH assay to MIRP provides a quick and reliable intraoperative diagnostic modality in confirming correct adenoma removal. Moreover, it precludes the requirement of frozen section. This study was presented in the 39th Congress of the European Society for Surgical Research (ESSR), Athens, Greece, May 12–15, 2004. The abstract was published in European Surgical Research (Eur Surg Res 2004;36(suppl 1):1–148).  相似文献   
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Background The mechanism of prevention of gastric reflux into the esophagus is not exactly known. The lower esophagus has a barrier function provided by the lower esophageal sphincter. We investigated the hypothesis that the crural diaphragm shares in the barrier function not only mechanically but also actively through a crural–esophageal–gastric reflex action. Methods The study was performed during repair of abdominal ventral and incisional hernias in 20 subjects (11 men, 9 women; age 38.6 ± 4.8 years). The electromyographic response of the crural diaphragm to individual balloon distension of esophagus and stomach was recorded by means of a needle electrode inserted into the crural diaphragm and connected to an electromyographic apparatus. The recordings were repeated after separate crural, esophageal, and gastric anesthetization. Results The crural diaphragm exhibited basal motor unit action potentials, which decreased on esophageal distension (P < 0.001) after a mean latency of 17.3 ± 2.8 SD ms. The crural diaphragm response to esophageal distension did not occur after the crural diaphragm or esophagus was anesthetized. Gastric distension effected an increase of crural diaphragm electromyographic activity with a mean latency of 18.4 ± 4.6 ms; this effect could not be achieved after the crural diaphragm or stomach was anesthetized. Conclusions The crural diaphragm has a resting tone that relaxes after esophageal distension and contracts after gastric distension. This sphincter-like action of the crural diaphragm appears to be a reflex and is mediated through the esophagocrural inhibitory and gastrocrural excitatory reflexes. The crural diaphragm seems to share actively in the gastroesophageal competence mechanism.  相似文献   
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Background The definition of a clear margin in breast-conserving therapy is uncertain. The purpose of this study was to correlate the tumor-margin distance of the excision specimen with the presence of residual tumor at reoperation. We also analyzed predictors of compromised margins and of residual disease. Methods All patients who underwent breast-conserving therapy for invasive disease from 1999 to 2003 were reviewed. Pathologic characteristics and the precise tumor distance from the radial margin were recorded. A radial margin was compromised if invasive or (ductal) in situ carcinoma was <5 mm from the margin. Results Of the 612 patients who underwent breast conservation, 211 (34%) had compromised margins, and 39 had undetermined margins. Of the 161 patients who had a reoperation for compromised margins, 87 (54%) had residual disease. Residual disease after reoperation was present in 58% (56 of 96), 56% (9 of 16), and 45% (22 of 49) of those with tumor-margin distances <1 mm, ≥1 and <2 mm, and ≥2 and <5 mm, respectively. There was a progressive decline in residual disease for each millimeter until a rate of 22% for tumor-margin distances of ≥4 mm and <5 mm was reached. Pathologic size (P = .004), an extensive intraductal component (P = .002), referral from a symptomatic rather than a population-based screening program (P = .02), and the absence of a preoperative diagnosis by core biopsy (P < .0001) were predictive of compromised margins. Only young age (<45 years) was predictive of finding residual disease on reoperation (P = .02). Conclusions A total of 45% of patients who had tumor 2 to 5 mm from the radial margin had residual disease on reoperation. Our results support a policy of requiring a 5-mm margin in patients undergoing breast-conserving therapy for invasive disease.  相似文献   
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Background. There is scanty information on the outcome of adult congenital heart disease surgery from the developing world. Methods. This was a retrospective chart review of the surgical outcome of 153 adults with congenital heart disease over a 5‐year period. Surgical atrial septal defect closure was considered “simple” while all other surgeries were considered “complex.” Results. There were 102 patients in the “simple” group and 51 in the “complex” group. Only three (2%) patients had prior operations. The “complex” group had longer bypass time and cross clamp time. Intensive care unit stay, ventilation time, and inotrope administration were longer. Major complications were more common and there were two deaths in the “complex” group. Age more than 30 years, cyanosis, and New York Heart Association class more than II were predictors of longer stay in the intensive care unit. Surgical repair of Tetralogy of Fallot in adults tended to have a longer ventilation time and intensive care unit stay with a mortality of 4%. At follow up, all patients were in New York Heart Association class I or II. Improvement of the functional class with negligible adverse events was noted in both groups. Conclusions. A retrospective evaluation of 153 adults with congenital heart disease who underwent open heart surgery at a single center in India showed strikingly fewer reoperations compared with large European studies. There was a similar prevalence of complex lesions. Surgical mortality was low, and long‐term functional outcome was gratifying.  相似文献   
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