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61.
Perineural invasion has been widely regarded as a poor prognostic factor in cancer of the oral cavity, but adjuvant treatment based only on this is still debatable. We have made an effort to address the question in a retrospective analysis of data from 2009–15 of patients with early node-negative cancers of the oral cavity. Patients with perineural invasion were divided into those who were treated with radiotherapy and those who were not. The records of a total of 169 patients were analysed, and 118 were given adjuvant radiotherapy and 51 were not. The median (range) duration of follow up was 45 (26–86) months. Of 169 patients, 47 (28%) developed recurrence, 28 in the treated, and 19 in the untreated, group. There was a significant disease-free survival benefit for adjuvant treatment (p = 0.047) but no overall survival benefit (p = 0.54).We conclude that adjuvant radiotherapy should be considered for patients with perineural invasion, even in early cancers of the oral cavity.  相似文献   
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The purpose of this study was to analyze the CSF flow in patients with Chiari I to determine differences between patients with and without CAH. Thirty patients with Chiari I malformation underwent cine-PC CSF flow imaging in the sagittal plane. CSF flow pulsations were analyzed by placing regions of interest in the anterior cervical subarachnoid space. Maximum CSF systolic (craniocaudal) and diastolic (caudocranial) velocities as well as the durations of CSF systole and diastole (measured in fractions of the cardiac cycle) were determined. In the region of interest just below the foramen magnum, patients with CAH had a significantly shorter CSF systole and longer diastole (P=.02). A CSF diastolic length of ≥0.75 of the cardiac cycle was 67% sensitive and 86% specific for CAH. Our results indicate that Cine-PC imaging can show differences in CSF flow patterns in patients with Chiari I with and without CAH.  相似文献   
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RATIONALE AND OBJECTIVES: Members of the Society of Chairmen of Academic Radiation Oncology Programs (SCAROP) were surveyed in November 1997 to evaluate the current status of radiation oncology training in the United States and to help determine how it should be carried out in the coming decade. MATERIALS AND METHODS: A detailed questionnaire was sent to all members of SCAROP; 68 of 82 questionnaires were returned, for a response rate of 83%. RESULTS: The responses to the survey show a serious shortage of radiation oncologists in university settings, despite an apparent surplus in private practice. Although recent changes in health care have added additional clinical responsibilities for radiation oncologists in university practices, approximately 75% of the chairpersons answering the survey continue to give their faculty protected time for research. Even with additional research and teaching responsibilities, the average radiation oncologist in university practice saw 206 patients per year in 1997, a number similar to that reported by the Patterns of Care Study for radiation oncologists overall. Approximately two-thirds of respondents believe that academic chairs should strive to have all clinical faculty members participating in research. Nevertheless, most think that basic research is better performed by dedicated researchers with PhD degrees rather than radiologists with MD degrees. Most respondents believe that the training programs adequately prepare radiation oncologists for a career in academic medicine but do not provide good training in research. Eighty-four percent agreed that resident performance on the American Board of Radiology examination should be considered in the accreditation of residency programs in radiation oncology but should not be the major criterion. CONCLUSION: There is a shortage of academic radiation oncologists in the United States despite the large number of radiation oncologists completing training. This probably is due to a variety of factors, including a relatively small pool of candidates for academic positions, increasing demands for performance from academic physicians (to see more patients, perform research, publish, write grants, and teach), and competition from the private sector for recruitment of these individuals.  相似文献   
64.
Background : During a 10-year period (1986–95), 70 adult Papua New Guineans with head and neck lymphomas were seen in the 18 years-and-above age group. Methods : The clinical information was obtained from the medical records section of the Port Moresby General Hospital. Relevant treatment modalities and the follow-up data were acquired from the National Cancer Centre, Angau Memorial Hospital, Lae. Results : Of a total of 227 adult lymphomas recorded in a 10-year period, 70 cases were seen in the head and neck region. Non-Hodgkin’s lymphoma constituted 56 cases, which included seven cases of adult Burkitt’s-like lymphoma. Fourteen cases of Hodgkin’s lymphoma were recorded. Conclusions : In Papua New Guinea, malignant lymphomas primarily affecting the head and neck region were seen in 30.8% of all lymphomas. This constitues 2.8% of all malignancies in this region. These lymphomas appear to be more aggressive at this site. Proper tissue diagnosis and combination chemoradiotherapy are the key factors in its management.  相似文献   
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Gastric cancer is a common malignancy in our country and patients continue to present at an advanced stage. Following confirmation of diagnosis, CT scan, endoscopic ultrasound and laparoscopy are the essential staging modalities. Radical gastrectomy remains the initial treatment of choice. Although controversy persists about the extent of lymph node dissection, there is a general consensus in performing D2 dissection but with preservation of pancreas and spleen. Patients who have high risk of relapse are treated with postoperative chemoradiotherapy. The regimen of preoperative chemotherapy followed by gastrectomy and postoperative chemotherapy has also become important in recent years. Both these chemotherapeutic options confer survival advantage and patients need to be appraised about various treatment strategies at the very outset.  相似文献   
67.
Peritoneal access and creation of pneumoperitoneum are the key initial steps of laparoscopic surgery. This is commonly achieved by either introducing Veress needle or by gradual dissection of all the layers of the abdominal wall and then introducing a port under direct vision. The two techniques are extremely safe, but large outcome studies have found slightly increased complications with the Veress needle. Randomized trials do not support such finding and both techniques continue to have their enthusiasts. We hereby describe an open method of initial port placement, wherein the port is introduced through the umbilical cicatrix under direct vision.  相似文献   
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Thirty children presenting with acute encephalopathic illness within a month of measles were studied. A male preponderance was found and 83.3% of cases were below 5 years of age. The interval between onset of measles rash and that of encephalopathy ranged from 0 to 20 days. Fever (96.6%), convulsions (70%), and coma (90%) were found in a high percentage of cases, while focal neurological deficits and abnormal movements were found in a small number of patients (3.3% and 16.6% respectively). Signs of cerebellar or medullar involvement were not seen. Only 1 (3.3%) case had pleocytosis in the cerebrospinal fluid. Eleven (36.6%) patients died in hospital. The pathogenesis of acute encephalopathy following measles is discussed. An erratum to this article is available at .  相似文献   
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