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91.
Dermabrasion     
This review presents skin anatomy, dermabraders, indications for dermabrasion and microdermabrasion, and dermabrasion techniques for the face, along with potential complications. Dermabrasion is a minimally invasive technique used for skin resurfacing. Its applications include treatment of rhytids, abnormal scarring, and premalignant lesions. The risks of complications are low and include pigment changes, hypertrophic scarring, and infection. Despite the introduction of newer therapies, such as lasers and chemical peels, dermabrasion remains an effective tool for physicians to combat the effects of aging without the downtime required for surgery.  相似文献   
92.

Background

Over the last few decades medical research and development has come to depend more heavily on the financial support of industry. However, there is concern that financial relations between the medical community and medical industry could unduly influence medical research and therefore patient care. Our objective was to determine whether conflict of interest owing to authors’/investigators’ financial affiliation with industry associated with their academic research has been identified in the surgical literature. In particular, we sought to answer the following questions: What is the extent of such conflict of interest? Does conflict of interest bias the results of academic surgical research in favour of industry? What are the potential causes of this proindustry bias?

Methods

We conducted a systematic review of the literature in May 2008 using the OVID SP search engine of MEDLINE, EMBASE, CINAHL, the Cochrane Database of Systematic Reviews, DARE and Health Technology Assessment. Quantitative studies that included a methods section and reported on conflict of interest as a result of industry funding in surgery-related research specifically were included in our analysis.

Results

The search identified 190 studies that met our criteria. Author/investigator conflict of interest owing to financial affiliation with industry associated with their academic research is well documented in the surgical literature. Six studies demonstrated that authors with such conflicts of interest were significantly more likely to report a positive outcome than authors without industry funding, which demonstrates a proindustry bias. Two studies found that the proindustry bias could not be explained by variations in study quality or sample size.

Conclusion

The conflict of interest that exists when surgical research is sponsored by industry is a genuine concern.  相似文献   
93.
PURPOSE: Laparoscopic partial/wedge nephrectomy, similar to laparoscopic radical prostatectomy, is a technically challenging procedure that is performed by a limited number of expert laparoscopic surgeons. The incorporation of a robotic surgical interface has dramatically increased the use of minimally invasive pelvic surgery such that robotic laparoscopic radical prostatectomy is commonly performed even by laparoscopically na?ve surgeons. This analysis compares the outcomes of our initial experience with robot-assisted laparoscopic partial nephrectomy (RLPN) performed by an experienced open surgeon to that of standard laparoscopic partial nephrectomy (LPN) performed by two experienced laparoscopic surgeons. PATIENTS AND METHODS: We reviewed the medical records of 11 consecutive patients who underwent 12 standard LPNs (EMM, RVC) (one patient had two unilateral tumors) and 10 consecutive patients (representing the first 11 of such robotic procedures performed at our institution) who underwent 11 RLPNs (one patient had bilateral tumors managed in an asynchronous manner) (DKO). RESULTS: The mean tumor size was 2.3 cm (range 1.7-6.2 cm) for LPN and 3.1 cm (range 2.5-4 cm) for RLPN. The mean total procedure time was 289.5 minutes (range 145-369 min) for LPN and 228.7 minutes (range 98-375 min) for RLPN (P=0.102). The mean estimated blood loss was 198 mL (range 75-500 mL) for LPN v 115 mL (25-300 mL) for RLPN (P=0.169). The mean warm ischemia time was 35.3 minutes (range 15-49 min) in the LPN group and 32.1 minutes (range 30-45 minutes) in the RLPN group (P=0.501). CONCLUSIONS: Introducing a robotic interface for laparoscopic partial/wedge resection allowed a fellowship-trained urologic oncologist with limited reconstructive laparoscopic experience to achieve results comparable to those for laparoscopic partial/wedge resection performed by experienced laparoscopic surgeons. In this regard, the learning curve appears truncated, similar to that with robot-assisted laparoscopic prostatectomy.  相似文献   
94.
OBJECTIVE: Because chylothorax complicating thoracic surgery is difficult to diagnose and failure of nonoperative management necessitates further surgery, we critically evaluated an evolving percutaneous strategy for diagnosing and treating chylothorax. METHODS: After thoracic surgery, 37 patients with a clinical diagnosis of chylothorax were referred for lymphangiography for definitive diagnosis and percutaneous treatment. Successful localization of the cisterna chyli by lymphangiogram facilitated percutaneous cannulation of the thoracic duct and its embolization. In patients in whom cannulation was not possible, the thoracic duct was percutaneously disrupted. RESULTS: Diagnosis: Lymphangiography was successful in 36 of the 37 patients (97%). Contrast extravasation, confirming clinical diagnosis, was present in 21 of the 36 (58%). Management: Twenty-one of 36 patients underwent 22 lymphangiographically directed percutaneous interventions: 12 embolizations and 10 disruptions. Mortality was zero, with two manageable complications. Patients without percutaneous intervention were discharged a median of 7 days (range 4-58) after first lymphangiography, 8 days (range 2-19) after percutaneous embolization, and 19 days (range 6-48) after first disruption. Eight patients had nine subsequent reoperations for chylothorax, two with negative lymphangiograms; no embolization patient required reoperation. CONCLUSIONS: There is a discrepancy between the clinical diagnosis of chylothorax after thoracic surgery and the presumed gold standard of diagnosis, contrast extravasation at lymphangiogram. Percutaneous treatment by thoracic duct embolization or disruption is safe and may obviate reoperation, but embolization of the thoracic duct is preferable to its disruption.  相似文献   
95.
As surgeons become more aggressive in treating aneurysms with endovascular techniques, traditional surgical principles of preserving internal iliac arteries and the inferior mesenteric artery have been challenged. A case is presented where the T-Stat device (Spectros Corp, Portola Valley, Calif), an optical real-time sensor approved by United States Food and Drug Administration for measuring colon ischemia, was used as an adjunctive measure to assist in the successful endovascular aneurysm repair in a patient at high risk for colon ischemia.  相似文献   
96.
OBJECTIVE: The purpose of this study was to examine the effects of resorbable bone cement on screw and plate-screw fracture fixation in a porous osteoporotic bone model. METHODS: Experiment 1: Screw pullout strength was assessed for 4 sets of 4.5-mm cortical screws inserted into a synthetic osteoporotic cancellous bone model, including screws inserted without cement augmentation (control), screws augmented with tricalcium phosphate (TCP) bone cement (Norian SRS; Synthes USA, Paoli, PA), and screws augmented with polymethylmethacrylate. Experiment 2: The effects of cement augmentation on plate-screw fixation strength were examined by performing cantilever bending tests on 4 sets of 8 plate-screw constructions, including nonaugmented and TCP-augmented standard and locked screw-plate constructions in a similar bone model. RESULTS: Experiment 1: Cement augmentation with both TCP and polymethylmethacrylate increased screw pullout strength from a porous osteoporotic cancellous bone model by about 4-fold (P < 0.05), and there was no significant difference between the 2 cements (P > 0.1). Experiment 2: Fixation strength was 1.5 times higher for locked plates compared with standard plates when neither was augmented with cement (P = 0.07). Cement augmentation with TCP improved fixation strength by 3.6 times for a standard plate-screw construction (P < 0.05) and 3.3 times for a locked plate-screw construction (P < 0.05). The most stable construction was the TCP-augmented locked plate, in which a 5-fold increase was observed compared with that of standard plates without TCP (P < 0.05). CONCLUSIONS: This study indicates augmenting screws with TCP cement during osteosynthesis improves fixation strength in an osteoporotic cancellous bone model. CLINICAL RELEVANCE:: In fracture situations in which osteoporotic bone makes screw and screw-plate fixation tenuous, screw augmentation with TCP cement should be considered as adjunct treatment.  相似文献   
97.
98.
BACKGROUND: Few in vivo models of esophageal reflux and fundoplication suitable for the study of the pathogenesis of Barrett's esophagus and esophageal cancer exist. We describe a modification of a rat model of duodenoesophageal reflux that incorporates Nissen fundoplication and uses it to study the role of fundoplication in ameliorating esophageal reflux. METHODS: A previously described rat model of duodenoesophageal reflux was modified to include Nissen fundoplication. Reflux threshold (RT), defined as the gastric pressure required to cause gastroesophageal reflux during transgastric instillation of saline, was measured in 12 Sprague-Dawley rats at baseline, after cardiomyotomy with esophagogastroduodenal anastomosis (EGDA), after subsequent Nissen fundoplication, and, finally, after takedown of Nissen fundoplication (NF). RESULTS: Cardiomyotomy with EGDA induced no significant change in RT compared with baseline (mean RT +/- SD: 4.0 +/- 1.9 mmHg and 6.0 +/- 2.5 mmHg, respectively, p = 0.741). Nissen fundoplication led to a 14-fold increase in RT (56.4 +/- 18.2 mmHg) compared with cardiomyotomy. RT pressure reverted to baseline levels after NF takedown (4.7 +/- 2.9 mmHg, p < 0.001). Antegrade esophageal flow was demonstrated without an increase in distal esophageal pressure after NF. CONCLUSIONS: Nissen fundoplication creates a one-way antireflux mechanism that eliminates gastroesophageal reflux in this rat model. This modification of an in vivo model of duodenoesophageal reflux represents a unique opportunity to investigate the effect of NF on cardiomyotomy-induced reflux and distal esophageal exposure to duodenogastric refluxate, and could be useful in the study of the role of NF in preventing progression to BE and ECA.  相似文献   
99.
PURPOSE: To compare our experience with laparoscopic radical cystectomy (LACIC) and robot-assisted laparoscopic radical cystectomy (RACIC) with ileal conduit urinary diversion. PATIENTS AND METHODS: Prospective data were gathered on 20 consecutive patients undergoing LACIC performed between August 2002 and July 2005, and on 14 consecutive patients undergoing RACIC performed between March 2005 and December 2006. Radical cystectomy with pelvic lymphadenectomy was performed laparoscopically or robotically, and an ileal conduit urinary diversion was performed extracorporeally. RESULTS: There was no significant difference in terms of preoperative factors or baseline tumor characteristics and no significant difference in mean operative time (410 min v 419 min) between groups. There was less blood loss (212 mL v 653 mL; P < 0.0001) and fewer transfusions (42.8% v 70%; P < 0.0011) in the RACIC group. There was one intraoperative complication (7%) and no conversions in the RACIC group. There were three (15%) intraoperative complications all leading to conversion in patients undergoing LACIC. Three (21%) patients in the RACIC group and 10 (50%) patients in the LACIC group had at least 1 post-operative complication. The mean number of days to oral intake was less in the RACIC group (2.3 v 6.1; P = 0.012). There was no significant difference in the number of lymph nodes excised (P = 0.09) between groups. Bilateral extended lymphadenectomy was performed in 10 (71%) RACIC patients with a mean of 22.3 lymph nodes harvested and in 16 (80%) LACIC patients with a mean of 16.5 lymph nodes harvested. There were no positive margins in patients in the LACIC group and one (7.1%) among patients in the RACIC group--a patient with pT4 disease. CONCLUSION: Both laparoscopic and robot-assisted radical cystectomies can be performed safely without compromising oncologic standards for surgical margins and extent of lymphadenectomy. In this early experience, the robot-assisted approach appears to have a shorter learning curve, and it is associated with less blood loss, fewer postoperative complications, and earlier return of bowel function than LACIC.  相似文献   
100.
BACKGROUND: Percutaneous transluminal angioplasty (PTA), although not the traditional therapy, seems to be a safe alternative for patients with critical limb ischemia who are believed to be unsuitable candidates for open surgery. However, the efficacy of PTA in this setting has not been analyzed. The purpose of this study was to compare the outcomes of PTA for limb salvage with outcomes of major limb amputation in physiologically impaired patients believed to be unsuitable for open surgery. METHODS: From a prospective vascular registry, 314 patients (183 underwent amputation, and 131 underwent complex PTA for limb salvage) were identified as physiologically impaired or unsuitable for open surgery. This was defined as having at least one of the following: functional impairment (homebound ambulatory or transfer only), mental impairment (dementia), or medical impairment (two of the following: end-stage renal disease, coronary artery disease, and chronic obstructive pulmonary disease). Patients undergoing PTA were compared with patients undergoing amputation by examining the outcome parameters of survival, maintenance of ambulation, and maintenance of independent living status. Parameters were assessed by using Kaplan-Meier life-table curves (log-rank test and 95% confidence intervals [CIs]) and hazard ratios (HRs) from the Cox model. RESULTS: PTA resulted in a 12-month limb salvage rate of 63%. Thirty-day mortality was 4.4% for the amputation group and 3.8% for the PTA group. After adjustment for age, race, diabetes, prior vascular procedure, dementia, and baseline functional status, PTA patients had significantly lower rates of ambulation failure (HR, 0.44; P = .0002) and loss of independence (HR, 0.53; P = .025) but had significantly higher mortality (HR, 1.62; P = .006) than amputees. However, when life tables were examined, the maintenance of ambulation advantage lasted only 12 months (PTA, 68.6%; 95% CI, 59.6%-77.7%; amputation, 48%; 95% CI, 40.4%-55.5%) and was not statistically significant at 2 years (62.2% [95% CI, 48.8%-71.5%] and 44% [95% CI, 35.8%-52.2%], respectively). Maintenance of independent living status advantage lasted only 3 months, with no statistically significant difference at 2 years (PTA, 60.5%; 95% CI, 45.4%-75.6%; amputation, 52.6%; 95% CI, 40.4%-64.9%). Although mortality was high in both cohorts, patients who underwent amputation had a survival advantage for all time intervals examined (at 2 years: PTA, 29%; 95% CI, 19.9%-38.1%; amputation, 48.1%; 95% CI, 39.2%-56.9%). CONCLUSIONS: Patients who present with critical limb ischemia and physiologic impairments that preclude open surgery seem to have comorbidities that blunt any functional advantage achieved after PTA for limb salvage. PTA in this setting affords very little benefit compared with amputation alone.  相似文献   
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