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991.
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993.
The role of interferon as adjuvant therapy in stage III melanoma has recently been questioned. Prospective randomized studies have shown conflicting results regarding the efficacy of adjuvant treatment. The purpose of this study was to examine the use of low-dose adjuvant interferon alpha2-b (IFN) in stage III melanoma patients treated at a single institution. This study was a retrospective analysis of 60 stage III melanoma cases from Wake Forest University treated between 1983 and 1998. Cases were identified via the tumor registry. All patients underwent standard lymphadenectomy after diagnosis. After recovery from surgery patients were offered low-dose IFN (3 million units subcutaneous TIW for 1 month and then 6 million units subcutaneous TIW for 11 months) as adjuvant therapy for stage III melanoma. The patients were followed up jointly by medical and surgical oncology. There were 39 male and 21 female patients with mean age of 60.0 (range 37-89) years. The average number of positive nodes was 3.6 (median = 1) for the treated group and 1.8 (median = 1) for those untreated (P = 0.71). The average tumor thickness was similar between groups: 4.71 versus 4.88 mm for the IFN and observation groups respectively. The IFN group (N = 25) that received low-dose treatment had a median survival of 7.9 years with a 5-year survival rate of 69 per cent. The 35 cases that did not receive interferon had a median survival of 6.5 years and a 5-year survival rate of 52 per cent. These survival rates were not significantly different (P = 0.91). The median disease-free survival for patients who did not receive IFN treatment was 2.4 years and 1.4 years for the treated group (P = 0.19). The data show that there was similar survival for those who did and did not receive the low-dose IFN treatment. Although only large prospective trials can conclusively exclude a small survival time this experience suggests that there is no significant survival advantage to low-dose adjuvant IFN therapy for stage III melanoma patients. Hopefully upcoming cooperative group trials will clarify the potential value of adjuvant IFN in this setting. However, although the toxicity of this regimen was mild we suggest that low-dose adjuvant IFN for stage III melanoma should not be utilized outside the setting of a clinical trial.  相似文献   
994.
Pulse oximetry probes placed peripherally may fail to give accurate values of blood oxygen saturation when the peripheral circulation is poor. Because central blood flow may be preferentially preserved, we investigated the oesophagus as an alternative monitoring site. A reflectance blood oxygen saturation probe was developed and evaluated in 49 patients undergoing cardiothoracic surgery. The oesophageal pulse oximeter results were in good agreement with oxygen saturation measurements obtained by a blood gas analyser, a CO-oximeter and a commercial finger pulse oximeter. The median (IQR [range]) difference between the oesophageal oxygen saturation results and those from blood gas analysis were 0.00 (-0.30 to 0.30 [-4.47 to 2.60]), and between the oesophageal oxygen saturation results and those from CO-oximetry were 0.75 (0.30 to 1.20 [-1.80 to 1.80]). Bland-Altman analysis showed that the bias and the limits of agreement between the oesophageal and finger pulse oximeters were -0.3% and -3.3 to 2.7%, respectively. In five (10.2%) patients, the finger pulse oximeter failed for at least 10 min, whereas the oesophageal readings remained reliable. The results suggest that the oesophagus may be used as an alternative monitoring site for pulse oximetry even in patients with compromised peripheral perfusion.  相似文献   
995.
HYPOTHESIS: Certain clinicopathologic factors predict improved survival after cytoreductive surgery and intraperitoneal hyperthermic chemotherapy for peritoneal carcinomatosis. DESIGN: Prospective clinical trial. SETTING: Surgical oncology service at a university academic hospital. PATIENTS: A population of 109 consecutive patients with peritoneal carcinomatosis treated between December 1991 and November 1997. INTERVENTION: All patients underwent resection of gross disease followed by 2-hour intraoperative perfusion of mitomycin C (20-40 mg) into the peritoneal cavity at a temperature of 40.5 degrees C. MAIN OUTCOME MEASURES: Clinicopathologic factors that independently predicted improved overall survival rates. RESULTS: Overall survival at 1 and 3 years was 61% and 33%, respectively. With median follow-up of 52 months, median overall survival was 16 months. Four factors were significant independent predictors of improved survival by multivariate analysis: nonadenocarcinoma histologic features (P =.001), the appendix as a primary site (P =.003), the absence of hepatic parenchymal metastases (P =.01), and complete resection of all gross disease (R1/0 resection) (P<.001). Patients with an R1/0 resection vs an incomplete resection of gross disease (R2 resection) had 3-year overall survival of 68% vs 21% (P<.001). CONCLUSIONS: Patients with peritoneal carcinomatosis have a uniformly poor prognosis. However, in select patients, the natural history of this disease condition may be altered by using the multimodality approach of cytoreductive surgery and intraperitoneal hyperthermic chemotherapy. These results require confirmation in prospective randomized studies.  相似文献   
996.
Bone marrow-derived cells including osteoblastic progenitors can be concentrated rapidly from bone marrow aspirates using the surface of selected implantable matrices for selective cell attachment. Concentration of cells in this way to produce an enriched cellular composite graft improves graft efficacy. The current study was designed to test the hypothesis that the biologic milieu of a bone marrow clot will significantly improve the efficacy of such a graft. An established posterior spinal fusion model and cancellous bone matrix was used to compare an enriched cellular composite bone graft alone, bone matrix plus bone marrow clot, and an enriched bone matrix composite graft plus bone marrow clot. Union score, quantitative computed tomography, and mechanical testing were used to define outcome. The union score for the enriched bone matrix plus bone marrow clot composite was superior to the enriched bone matrix alone and the bone matrix plus bone marrow clot. The enriched bone matrix plus bone marrow clot composite also was superior to the enriched bone matrix alone in fusion volume and in fusion area. These data confirm that the addition of a bone marrow clot to an enriched cell-matrix composite graft results in significant improvement in graft performance. Enriched composite grafts prepared using this strategy provide a rapid, simple, safe, and inexpensive method for intraoperative concentration and delivery of bone marrow-derived cells and connective tissue progenitors that may improve the outcome of bone grafting.  相似文献   
997.
PURPOSE: We examine the complication and continence rates with early catheter removal (day 3 or 4) after radical retropubic prostatectomy. MATERIALS AND METHODS: A total of 365 patients with localized prostate cancer underwent radical retropubic prostatectomy at Indiana University Hospital with planned urethral catheter removal before discharge home. Low pressure cystograms were performed on postoperative day 3 or 4 to determine if catheter removal was possible. A subset of patients were analyzed using a validated prostate cancer specific questionnaire (University of California, Los Angeles Prostate Cancer Symptom Index) to determine quality of life outcomes. RESULTS: The catheter was removed on postoperative day 3 or 4 in 263 patients (72%). The reasons for leaving the catheter indwelling were significant leak on cystogram or excessive suprapubic drainage (21%), extensive bladder neck reconstruction (1%) and prolonged hospitalization because of an ileus or other complicating factor (6%). Thirteen patients (3.6%) were either unable to void after catheter removal or presented with retention (not associated with hematuria or clots) after hospital discharge, requiring reinsertion of the Foley catheter. A total of 41 patients (11%) had either an early or late complication (excluding incontinence). There were 3 complications (0.8%) that were considered major because they were potentially life threatening or required a return to the operating room. A pelvic abscess developed in 2 patients and a lymphocele in 1, which required percutaneous drainage. After at least 6 months (mean 20.9 months) 140 patients (89.2%) and 14 (8.9%) reported excellent and good continence, respectively. The patient questionnaire demonstrated bother scores to be minimal to no bother for 95% to 98% of patients at 6 and 12 months. CONCLUSIONS: This study confirms that it is safe to remove catheters in most patients 3 to 4 days after prostatectomy if a cystogram demonstrates no extravasation. Complication rates and continence rates with this approach compare favorably with series in which catheters are left indwelling for longer periods.  相似文献   
998.
Despite significant advances in hearing protection and compliance with protective standards, military personnel are still subject to noise-induced hearing loss in many combat and combat support operations. Although the Army has experienced a decrease of some 15% in primary hearing loss disability cases since 1986, a fiscal year 2000 report documents a 27.5% increase in audiograms, which demonstrated significant threshold shifts in assessed personnel (N = 841/1,077). Compensation for noise-induced hearing loss disability for the Army alone exceeded $180 million in 1998. Thus, communications and hearing protection remain critical issues for personnel involved in Army operations. Aircraft, ground vehicles, and weapons produce noise levels in excess of the limits defined in current hearing conservation standards. Performance of most helmets, improved over the years, remains marginal with regard to speech intelligibility. Furthermore, these helmets do not provide adequate hearing protection. The communications earplug, which consists of a high-quality earphone coupled with an earplug protector, provides the needed extra protection. It weighs less than 15 g and is comfortable when worn over extended periods. It is considered highly acceptable by seasoned Army aviators and crewmembers.  相似文献   
999.
In today's health-conscious society, more people are participating in athletic endeavors. As participation increases, so does the incidence of cervical injuries. Fortunately, most of the cervical injuries seen in sports are minor and can be treated successfully with minimal morbidity. It is important, however, to accurately assess the patient sustaining a cervical injury to rule out the presence of a more severe cervical injury. When practitioners understand the pathophysiology and treatment of common injuries, including sprains, strains, contusions, disc herniations, and simple fractures, most athletes can be returned to full function.  相似文献   
1000.
In May 2000, the radiology department at Stanford University Medical Center embarked on a five-year journey toward complete digitization. While the end goal was known, there was much less certainty about the steps involved along the way. Stanford worked with a team from GE Medical Systems to implement Six Sigma process improvement methodologies and related change management techniques. The methodical and evidence-based framework of Six Sigma significantly organized the process of "going digital" by breaking it into manageable projects with clear objectives. Stanford identified five key areas where improvement could be made: MR outpatient throughput, CT inpatient throughput, CT outpatient throughput, report turnaround time, and Lucile Packard Children's Hospital CR/Ortho throughput and digitization. The CT project is presented in this article. Although labor intensive, collecting radiology data manually is often the best way to obtain the level of detail required, unless there is a robust RIS in place with solid data integrity. To gather the necessary information without unduly impacting staff and workflow at Stanford, the consultants working onsite handled the actual observation and recording of data. Some of the changes introduced through Six Sigma may appear, at least on the surface, to be common sense. It is only by presenting clear evidence in terms of data, however, that the improvements can actually be implemented and accepted. By converting all appointments to 30 minutes and expanding hours of operation, Stanford was able to boost diagnostic imaging productivity, volume and revenue. With the ability to scan over lunch breaks and rest periods, potential appointment capacity increased by 140 CT scans per month. Overall, the CT project increased potential for outpatient appointment capacity by nearly 75% and projected over $1.5 million in additional annual gross revenue. The complex process of moving toward a digital radiology department at Stanford demonstrates that healthcare cannot be healed by technology alone. The ability to optimize patient services revolves around a combination of leading edge technology, dedicated and well-trained staff, and careful examination of processes and productivity.  相似文献   
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