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991.

Background  

Liver transplantation in presence of diffuse portal vein thrombosis is possible by using caval blood as portal inflow, through cavo-portal transposition. However, clinical results are heterogeneous and experimental studies are needed, but similar hemodynamic conditions are difficult to obtain, especially in small animals. Herein we describe a new simple model of cavo-portal transposition in rat.  相似文献   
992.

Background  

There are few effective strategies reported for the primary prevention of low back pain (LBP). Core stabilization exercises targeting the deep abdominal and trunk musculature and psychosocial education programs addressing patient beliefs and coping styles represent the current best evidence for secondary prevention of low back pain. However, these programs have not been widely tested to determine if they are effective at preventing the primary onset and/or severity of LBP. The purpose of this cluster randomized clinical trial is to determine if a combined core stabilization exercise and education program is effective in preventing the onset and/or severity of LBP. The effect of the combined program will be compared to three other standard programs.  相似文献   
993.
994.
Background Treatment of locally advanced rectal carcinoma (LARC) often involves exenterative surgery, which can be associated with high perioperative morbidity and mortality. To assist in patient selection for radical surgery, we sought to determine clinicopathologic factors influencing recurrence and disease-free survival (DFS) of LARC. Methods Consecutive patients with LARC undergoing exenterative surgery were retrospectively identified in our institutional database. Factors evaluated included age, sex, primary versus recurrent tumors, neoadjuvant or adjuvant chemoradiotherapy, resection margin status, recurrence, time to recurrence, and survival. The primary outcome was DFS. Secondary outcomes were overall survival and perioperative morbidity. Results A total of 72 patients were identified; median age was 52 years, and median follow-up time was 30 months. The overall complication rate was 43%; rates were similar among the patients with primary (47%) or recurrent (37%) LARC. Primary or recurrent tumor status was the only factor significantly predictive of outcome after exenteration. Local recurrence rates were lower in the primary group (primary 22%, recurrent 52%, P = .05). A significant difference in 5-year DFS was found between primary and recurrent tumor (52% vs. 13%; P < .01). The median time to recurrence was longer in the patients with primary LARC (17 months vs. 8 months; P < .01). Conclusions The complication rates for pelvic exenteration remain high, but the morbidity can typically be managed without a clinically important increase in hospitalization. In primary LARC, an aggressive surgical approach provides most patients 5-year DFS. Select patients with recurrent LARC will also benefit from pelvic exenteration. Presented at the Society of Surgical Oncology Cancer Symposium, March 23–26, 2006.  相似文献   
995.
Abstract 10 embalmed cadaver forearms and wrists were dissected to determine the anatomical course of the superficial branch of the radial nerve in the distal forearm. The superficial radial nerve bifurcated in two branches at a mean of 54,7 mm proximal to the radial styloid. From the styloid process of the radius, the mean distance to the closest dorsal branch of the superficial radial nerve was 3,5 mm and the mean distance to the closest volar branch was 9,8 mm. The mean distance between the closest branch of the superficial radial nerve and Lister?s tubercle was 16,4 mm. The crossing point between the nerve and the cephalic vein was located at a mean of 54,3 mm proximal to the styloid process. At the level of styloid process the mean distance between the closest dorsal branch of the superficial radial nerve and the first dorsal compartment was 15,2 mm and between the closest volar branch and the first dorsal compartment 4,4 mm. Detailed knowledge of anatomic characteristics of the superficial branch of the radial nerve may help prevent injury during operations and treat traumatic lesions of the nerve. Because of great variations in the course of the superficial radial nerve we could not define an absolute safe zone for surgical procedures on the distal forearm. Iatrogenic lesions of the superficial radial nerve are described complications of percutaneous procedures. Therefore open surgical approaches are recommended. Daniela Klitscher and Lars Peter Müller contributed equally to this work.  相似文献   
996.
Survival after resection of colorectal liver metastases has traditionally been associated with clinicopathologic factors. We sought to investigate whether echogenicity of colorectal liver metastasis as assessed by intraoperative ultrasound (IOUS) was a prognostic factor after hepatic resection. Prospective data on tumor IOUS appearance were collected in 84 patients who underwent hepatic resection for colorectal liver metastasis. Images were digitally recorded, blindly reviewed, and scored for echogenicity (hypo-, iso-, or hyperechoic). The median tumor number was 1 and the median tumor size was 5.0 cm. At the time of surgery, the IOUS appearance of the colorectal liver metastases were hypoechoic in 35 (41.7%) patients, isoechoic in 37 (44.0%) patients, and hyperechoic in 12 (14.3%) patients. Traditional clinicopathologic prognostic factors were similarly distributed among the three echogenicity groups (all p > 0.05). Patients with a hypoechoic lesion had a significantly shorter median survival (30.2 months) compared with patients who had either an isoechoic (53.2 months) or hyperechoic (42.3 months) lesion (p = 0.005). The 5-year survival after hepatic resection of colorectal liver metastasis was also associated with the echogenic appearance of the lesion (hypoechoic 14.4 vs isoechoic 37.4 vs hyperechoic 46.2%) (p < 0.05). Intraoperative ultrasound echogenicity should be considered a prognostic factor after hepatic resection of metastatic colorectal cancer. This study was presented at the 47th annual meeting of The Society for Surgery of the Alimentary Tract, Los Angeles, CA, USA, 22 May 2006.  相似文献   
997.
Background Laparoscopic adrenalectomy (LA) is the preferred surgical approach for pheochromocytomas. We have investigated the changes in diagnosis, management and outcome of pheochromocytomas treated since the widespread advent of LA. Methods Data were collected retrospectively from 96 patients with pheochromocytomas that had been surgically treated at three tertiary referral centers. Results There were 53 females. Mean age was 47 years (10–81). Tumors were found incidentally in 40% of patients. Of the 96 patients, 12 (13%) had familial syndromes. CT or MRI localized the adrenal lesion in all patients. MIBG scans obtained from 32 patients were concordant with the CT/MRI in 19, were false negative in 9 and misleading in 1, and altered management in only 3 patients. Mean tumor size was 5.6 cm (1.8–17). There were 92 adrenal pheochromocytomas and 9 paragangliomas. Laparoscopy was successful in 67 of 74 (91%) patients, with 20 of 67 (30%) having tumors of 6 cm or greater in size. Conversions to open procedures were performed in patients with 4 left, 2 right pheochromocytomas and 1 paraganglioma. Of the patients, 22 had an open procedure due to suspicion of malignancy or large tumors. Malignancy was observed in 4 of 92 (4.3%) pheochromocytomas and 4 of 9 (44%) paragangliomas. Average follow-up was 22 months (1–122). There were seven recurrences. Postoperative biochemical tests available in 64 patients were normal in 90%. Conclusions The diagnosis of pheochromocytoma was made incidentally in 40% of patients. MIBG is not necessary for unilateral non-hereditary pheochromocytomas localized by CT/MRI. LA is possible with excellent results in most patients, including for treatment of lesions 6 cm or greater in size with no signs of invasion. Laparoscopy should be used cautiously for paragangliomas because of a high rate of malignancy.  相似文献   
998.
Background It has been suggested that obesity is associated with an altered rate of gastric emptying. The objective of the present study was to determine whether the rates of solid and semi-solid gastric emptying differ between morbidly obese patients and lean subjects. Methods The Gastric-emptying time (GET) of solid and semi-solid meals were compared between lean healthy subjects and morbidly obese patients enrolled in two previously published studies. GET of solid and semi-solid meals was measured using the 13C-octanoic acid breath test and 13C-acetic acid breath test, respectively, in 24 lean and 14 morbidly obese individuals of both sexes. Student t-test was used to compare the mean data between the lean and morbidly obese groups. The influence of sex, gender, BMI and morbid obesity on the GET of solid meals was verified by linear regression analysis. Results Mean t(1/2) values of solid GET (± standard deviation) were 203.6 ±  76.0 min and 143.5 ± 19.1 min for lean and obese subjects, respectively (P = 0.0010). Mean t(lag) values of solid GET were 127.3 ± 42.7 min and 98.4 ± 13.0 min for lean and obese subjects, respectively (P = 0.0044). No significant difference in semi-solid GET was observed between the lean and morbidly obese groups. Conclusion The present study demonstrated a significantly enhanced gastric emptying of the solid meal test in morbidly obese patients when compared to lean subjects. This finding is compatible with the hypothesis that rapid gastric emptying in morbidly obese subjects increases caloric intake due to a more rapid loss of satiety.  相似文献   
999.
The SRS-22 questionnaire is specifically designed for the assessment of quality of life in spinal deformity patients. This study is the first to use it to assess the quality of life of adolescent idiopathic scoliosis patients under brace treatment and compares the results with an observational group matched by age and curve magnitude. Forty-six patients were enrolled into each group. Overall, it was found that patients under observation had a significantly better quality of life than braced patients. Specifically, the domains for function/activity and self-image were most affected. This effect was most apparent in those with a curve magnitude of under 20 degrees . The scores did not improve significantly with the duration of brace wear, suggesting little adaptation. This study has implications for treatment, and more attention will need to be given to those with mild but progressive curves to help improve patients' understanding of their treatment and hence their compliance and satisfaction.  相似文献   
1000.
Background In breast carcinomas treated with neoadjuvant chemotherapy, intraoperative identification of residual tumors may be difficult. A well-tolerated, low-diffusion charcoal suspension has been designed to tattoo breast tumors. In this study, we investigated whether this tattooing technique is efficient for localizing the tumor after treatment with chemotherapy. Methods In a series of 109 patients with large breast tumors, a 4% or 10% charcoal suspension was injected at the time of the initial biopsy before preoperative chemotherapy. Results Tolerance was good. After three or four cycles of chemotherapy, 91 patients underwent conservative treatment, and the surgical specimen was examined intraoperatively. The charcoal was detected in 94% of the cases. The charcoal was seen in the nodule or at the periphery in the surgical specimen without any acute inflammatory reaction or diffusion. Conclusions On the basis of these results, this micronized charcoal suspension at a defined granulometry and a concentration of 10% seems to be ideal for tattooing breast carcinomas over a period of 3 months in patients in whom neoadjuvant chemotherapy is planned.  相似文献   
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