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BACKGROUND: It is essential that surgical trainees obtain adequate operative experience without compromising patient outcome. The aim of this study was to compare the reexcision and local recurrence rates between consultants (attending surgeons) and surgical trainees (residents) after breast conservation surgery. METHODS: Prospective data were obtained from the local breast cancer registry for all patients who had breast-conservation surgery between 1994 and 2000. Reexcision was carried out if the margins were deemed inadequate after taking the clinical and pathologic features into consideration. RESULTS: The primary operation (n = 505) was wide local excision = 377; wire-guided excisions = 107; and quadrantectomy = 21 patients. Sixty-five percent (n = 330) were operated on by consultants and 35% (n = 175) by residents. Second procedures (n = 137) were performed for involved margins in 95 and close margins in 31 patients. The patients in both groups were equally matched. The reexcision rate was similar for both groups of surgeons (P = 0.58). On multivariate analysis, the factors determining reexcision were nodal status, type of first procedure, and tumor type. The local recurrence rate was comparable in both groups (P = 0.33). CONCLUSIONS: In patients with breast cancer treated by conservation surgery during a 7-year period, the reexcision and local recurrence rates were similar for both groups of surgeons.  相似文献   
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Robotic assisted rectopexy   总被引:5,自引:0,他引:5  
BACKGROUND: During the last 3 years, robotic surgery has had a considerable impact on minimally invasive surgery in a wide range of specialties. This study describes the surgical technique and preliminary results of our first 6 cases of robotic assisted suture rectopexy. METHODS: During a period of 13 months 6 patients with full thickness rectal prolapse were operated on with the da Vinci surgical system. All patients were considered suitable for a suture rectopexy. Setting-up time, procedure time, patient recovery, and hospital stay were recorded and compared with the current literature. RESULTS: All operations were completed successfully using the robotic system. There were no major complications and no deaths. Mean setting-up time was 28 minutes, mean operation time was 127 minutes, and mean hospital stay was 6 days. At 3 to 6 months of follow-up all patients are in good health, with no signs of recurrence and no reports of constipation. CONCLUSIONS: Robotic assisted suture rectopexy is feasible and safe and apparently meets accepted standards of laparoscopic surgery.  相似文献   
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OBJECTIVE: This approach provides the basis of our research program, which aims to expand operative assessment beyond patient factors and the technical skills of the surgeon; to extend assessment of surgical skills beyond bench models to the operating theater; to provide a basis for assessing interventions; and to provide a deeper understanding of surgical outcomes. SUMMARY BACKGROUND DATA: Research into surgical outcomes has primarily focused on the role of patient pathophysiological risk factors and on the skills of the individual surgeon. However, this approach neglects a wide range of factors that have been found to be of important in achieving safe, high-quality performance in other high-risk environments. The outcome of surgery is also dependent on the quality of care received throughout the patient's stay in hospital and the performance of a considerable number of health professionals, all of whom are influenced by the environment in which they work. METHODS: Drawing on the wider literature on safety and quality in healthcare, and recent papers on surgery, this article argues for a much wider assessment of factors that may be relevant to surgical outcome. In particular, we suggest the development of an "operation profile" to capture all the salient features of a surgical operation, including such factors as equipment design and use, communication, team coordination, factors affecting individual performance, and the working environment. Methods of assessing such factors are outlined, and ethical issues and other potential concerns are discussed.  相似文献   
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Almost all primary retroperitoneal liposarcomas can be classified as well-/dedifferentiated liposarcoma. Rarely, however, primary retroperitoneal liposarcoma is classified as myxoid/round cell liposarcoma, based on the presence of myxoid areas and vascular crow's feet pattern, which has resulted in a debate on the classification of liposarcoma in the retroperitoneum. Genetically, myxoid/round cell liposarcoma and well-/dedifferentiated liposarcoma are different diseases. Myxoid/round cell liposarcoma is characterized by a translocation causing FUS-CHOP or EWSR1-CHOP fusion, whereas well-/dedifferentiated liposarcoma is characterized by an amplification of the 12q13-15 region, including MDM2 and CDK4 genes. As myxoid/round cell liposarcoma is highly radio- and chemosensitive, differentiation between subtypes is important to optimize treatment. We studied whether primary retroperitoneal liposarcomas diagnosed as myxoid/round cell liposarcoma represent molecularly true myxoid/round cell liposarcoma or are histopathological mimics and represent well-/dedifferentiated liposarcoma. Primary retroperitoneal myxoid/round cell liposarcoma (n=16) were compared to primary extremity myxoid/round cell liposarcoma (n=20). Histopathological and immunohistochemical features were studied. Amplification status of the 12q13-15 region was studied using a multiplex ligation-dependent probe amplification analysis, and FUS-CHOP or EWS-CHOP translocations were studied using RT-PCR. In primary retroperitoneal myxoid/round cell liposarcoma, MDM2 and CDK4 staining was both positive in 12 of 15 cases. In primary extremity myxoid/round cell liposarcoma, MDM2 was negative in 18/20 and CDK4 was negative in all cases. Multiplex ligation-dependent probe amplification showed the amplification of 12q13-15 region in 16/16 primary retroperitoneal myxoid/round cell liposarcomas and in 1/20 primary extremity myxoid/round cell liposarcomas. Translocation was present in all (18/18) primary extremity myxoid/round cell liposarcomas, but absent in all primary retroperitoneal myxoid/round cell liposarcomas. On the basis of immunohistochemical and molecular characteristics, apparent primary retroperitoneal myxoid/round cell liposarcoma can be recognized as well-/dedifferentiated liposarcoma with morphological features mimicking myxoid/round cell liposarcoma. In these cases, treatment should probably be specifically designed as for well-/dedifferentiated liposarcoma. Moreover, finding of myxoid/round cell liposarcoma translocations in a retroperitoneal localization is highly suggestive of metastasis and should prompt search for a primary localization outside the retroperitoneum.  相似文献   
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In vivo effect of toxaphene on calcium pump activity in rat brain P2 fraction was studied. Male Sprague-Dawley rats (200-250 g) were dosed with toxaphene at 0, 25, 50, and 100 mg/kg X d for 3 d and sacrificed 24 h after last dose. Ca2+-ATPase activity and 45Ca2+ uptake were determined in brain P2 fraction. Toxaphene decreased both Ca2+-ATPase activity and 45Ca2+ uptake, and the reduction was dose-dependent. Both substrate and Ca2+ activation kinetics of Ca2+-ATPase indicated noncompetitive type of inhibition, as evidenced by decreased catalytic velocity but not enzyme-substrate affinity. The decreased Ca2+-ATPase activity and 45Ca2+ uptake were restored to normal level by exogenously added calmodulin, which increased both velocity and affinity. The inhibition of Ca2+-ATPase activity and 45Ca2+ uptake and restoration by calmodulin suggests that toxaphene may impair active calcium transport mechanisms by decreasing levels of calmodulin.  相似文献   
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