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991.
Background: Colorectal adenomas are the usual precursors to carcinoma in sporadic and hereditary colorectal cancers (CRC).Methods: A total of 220 CRC patients (stages 0, I, and II) were randomized prospectively in a double-blind pilot study of calcium chemoprevention by using recurrent colorectal adenomas as a surrogate end point. This trial is still in progress, and we report the preliminary findings on adenoma recurrence rates.Results: Synchronous adenomas were present in 60% of patients, and cancer confined in a polyp was present in 23% of patients. The overall cumulative adenoma recurrence rate was 31% (19% in the first year, 29% for 2 years, and 35% for 3 years). The recurrence rates were greater for patients with synchronous adenomas: 38% at 3 years (P = .01). Lower stage was associated with higher adenoma recurrence rates (P = .04). Factors including age, sex, site of primary cancer, and whether the cancer was confined to a polyp were not significantly associated with differences in adenoma recurrence rates.Conclusions: The substantial adenoma recurrence rate in patients resected of CRC justifies colonoscopic surveillance on a periodic basis. Patients with higher rates of adenoma recurrences, such as CRC with synchronous adenomas, are ideal subjects for chemoprevention trials.  相似文献   
992.
Purpose: Early results of subfascial endoscopic perforator surgery (SEPS) were examined. Data on ulcer healing, complications, and costs are presented.Methods: Data were prospectively collected for all patients who underwent SEPS at our institution. A concurrent control group was not available because primary open perforator ligation is no longer performed at our hospital. Preoperative assessment included duplex scanning (valve closure times and perforator mapping), plethysmography, and phlebography. Completeness of therapy was assessed with postoperative duplex mapping of perforating veins. Clinical status was monitored after surgery, and actual costs, including equipment, personnel, and facilities management, are reported.Results: Eighteen procedures were performed in 15 patients (mean age, 52 years; range, 42 to 65 years). Two patients underwent bilateral SEPS, and one patient underwent a second procedure on the same leg. Active ulceration (class 6) was present in 14 of 18 limbs (78%), recently healed ulcers (class 5) in two of 18 (11%), and lipodermatosclerosis with edema (class 4) in two. Deep venous insufficiency was present in 14 of 18 (78%). The number of perforating veins ligated per leg ranged from 0 to 12 (mean, 4.3). Follow-up ranged from 3 to 64 weeks (mean, 22 weeks). Complete ulcer healing occurred in eight of 14 limbs (57%) at a mean of 14 weeks. Reduction in ulcer size was noted in four of 14 (29%), and two limbs were not improved. There were no new ulcers. Residual perforating veins were noted in four of 18 limbs. None of the limbs with residual perforating veins had complete healing of ulceration. Operating room costs were higher than those associated with limited-incision open perforator ligation ($2570 vs $1883).Conclusion: These preliminary data suggest that when used as part of a treatment plan to correct deep and superficial venous insufficiency SEPS results in a high rate of wound healing, with no recurrent ulceration in this series. Increased operating room costs associated with longer operations and greater disposable expenses will likely be overcome by shortened length of stay and diminished wound complications. These findings emphasize the importance of ligating all incompetent perforating veins, as ulcer healing was never achieved when residual perforating veins were found at follow-up. (J Vasc Surg 1997;25:995-1001.)  相似文献   
993.
994.
995.
BACKGROUND: Postoperative ileus (POI) remains an inevitable consequence of abdominal surgery. Although the pathogenesis of delayed gastrointestinal transit in the postoperative period has been the subject of considerable study, a clinically useful definition of what constitutes a pathologically prolonged ileus has yet to be established. The objectives of this study were to describe a definition for an abnormally prolonged ileus and to identify risk factors and predictors of prolonged ileus in patients undergoing abdominal surgery. MATERIALS AND METHODS: Over a 12-month period 88 patients who had abdominal surgery were retrospectively reviewed. The association of clinical factors with the duration of POI was examined with statistical tests. RESULTS: The mean time to commencing the consumption of unrestricted clear fluids after surgery was 2.3 +/- SD 1.6 days. The median duration of POI was 5 days (median 6 days), with an interquartile range of 3-6 days. Univariate regression analysis demonstrated significant correlations between duration of POI and estimated blood loss (EBL), total surgical time, and total opiate dose (TOD) (p = 0.009, p = 0.045, and p = 0.041, respectively). Multiple regression analysis identified EBL and TOD as independent predictors of duration of POI. CONCLUSIONS: We have identified two risk factors (EBL and TOD) that are independently associated with duration of POI. Our data suggest that with the definition of abnormal prolonged postoperative ileus as the number of days above the 3rd quartile, an ileus greater than 6 days serves as a better clinical definition of prolonged POI than 3 days, the measure that has previously been suggested.  相似文献   
996.
Despite improved technology for endovascular treatment of aorto iliac occlusive disease, aortobifemoral bypass (ABF) continues to offer superior long-term patency. In an effort to reduce the morbidity of surgical ABF, multiple minimally invasive techniques have been reported. The da Vinci robot may facilitate the construction of a minimally invasive aortic anastomosis using standard vascular suture techniques. Our initial experience in the development of a minimally invasive surgical aortic reconstruction program is reported. After extensive time in the laboratory developing our surgical technique in human cadavers and a pig model, our team initiated a robotic vascular surgery program in 2007. A retrospective review of our initial six robot-assisted laparoscopic ABF cases was conducted. The aorta was exposed laparoscopically using the Stadler technique and the aortic anastomosis performed with the da Vinci robot. These results are compared with currently published reports of robotic ABF and alternative methods of minimally invasive aortic reconstruction. From January 2007 to August 2007, six robot-assisted laparoscopic ABFs were performed. Two patients had prior abdominal surgical procedures. Four patients had prior endovascular or surgical aorto iliac reconstruction. Operative time varied from 5 h 26 min to 8 h 12 min. Total clamp time, for the aortic anastomosis, ranged from 70 to 100 min with a mean of 75 min. Estimated blood loss ranged from 300 to 2,000 ml with a mean of 850 ml. Conversion with a short upper midline incision was required in one patient (16%) with an associated abdominal aortic aneurysm. Post operative length of stay ranged from five to ten days with a median of seven days. There was no operative mortality. Results from robotically assisted laparoscopic ABF are equivalent to those from other minimally invasive options while enabling a much shorter learning curve. Using the technique described, minimally invasive ABF was accomplished in a safe and reliable manner despite prior vascular treatment.  相似文献   
997.
Objective To estimate the current prevalence, awareness and treatment status of hypercholesterolemia among inpatients with acute coronary syndrome (ACS) in China. Methods Sixty-four hospitals across China, including 32 secondary hospitals and 32 tertiary hospitals were selected for baseline survey. Fifty inpatients diagnosed with ACS were recruited consecutively in each participated hospitals. Retrospective information for 2751 patients were collected, and the prevalence, awareness, and treatment status of hypercholosterolemia among the patients were analyzed. Results (1) Mean age of the patients was 65±11. Sixty-nine percent of the patients were males and 31.2% were females. Among them, 39.4% were diagnosed as ST-segment elevation MI, 8. 8% as non-ST-segment elevation MI and 51.8% as unstable angina. Twenty-seven percent of them had previous ACS history. (2) Hypercholesterolemia was found in 19. 6% ACS patients. Among 7 geographic districts (north China, east China, south China, middle China, northeast, northwest and southwest), the prevalence rate of hypercholesterolemia was highest (24.7%) in east China and lowest (10.0%) in middle China. Significant difference was observed among these areas. (3) Awareness rate of hypercholesterolemia was 12.2% among patients with hypercholesterolemia, with significant difference among various areas. Treatment rate was 66.7% among patients with known hypercholesterolemia, with the highest (83.3%) seen in south China and lowest (0%) in southwest area. (4) The prevalence, awareness rate and treatment rate of hypercholesterolemia were higher in recurrent ACS patients than in those without ACS history. Conclusions Nearly 20% ACS inpatients have hypercholesterolemia. It is essential to pay more attention on the treatment of hypercholesterolemia for the purpose of secondary prevention of cardiovascular disease.  相似文献   
998.
This work aimed at evaluating the intragastric distribution of food in patients with GERD and dyspepsia and its relationship to acidic reflux episodes. Gastric emptying and food retention in the proximal stomach were evaluated by scintigraphy in 12 healthy subjects and 19 patients with GERD and dyspepsia after a liquid test meal. Patients also underwent 24-hr esophageal pH monitoring, which included a 2-hr postprandial period following a similar test meal. Total gastric emptying was similar in patients and controls, whereas proximal gastric retention (AUCprox/AUCtot) was significantly decreased in patients (mean +/- SD: 0.48 +/- 0.07 vs. 0.56 +/- 0.06; P = 0.02). Within the GERD-dyspepsia group, a significant negative correlation was found between proximal gastric retention and the number of acidic reflux episodes. We concluded that abnormally decreased retention of gastric contents in the proximal stomach after a liquid meal may contribute to the pathogenesis of acidic reflux episodes in patients with GERD and dyspepsia.  相似文献   
999.
Studies involving the transformation of lignocellulosic biomass into high value-added chemical products have been intensively conducted in recent years. Its matrix is mainly composed of cellulose, hemicellulose and lignin, being, therefore, an abundant and renewable source for obtaining several platform molecules, with levoglucosan (LG) standing out. This anhydrous carbohydrate can be acylated to obtain carbohydrate fatty acid esters (CFAEs). Here, these compounds were obtained via enzymatic acylation of LG, commercially obtained (Start BioScience®), with different acyl donors in continuous flow. Through the experimental design using a model reaction, it was possible to optimize the reaction conditions, temperature and residence time, obtaining a maximum conversion at 61 °C and 77 min. In addition, there was a productivity gain of up to 100 times in all comparisons made with the batch system. Finally, CFAEs were applied in tests of interfacial tension and biological activity. For a mixture of 4- and 2-O-lauryl-1,6-anhydroglucopyranose (MONLAU), the minimum interfacial tension (IFTmin) obtained was 96 mN m−1 and the critical micelle concentration (CMC) was 50 mM. Similar values were obtained for a mixture of 4- and 2-O-palmitoyl-1,6-anhydroglucopyranose (MONPAL), not yet reported in the literature, of 88 mN m−1 in 50 mM. For a mixture of 4- and 2-O-estearyl-1,6-anhydroglucopyranose (MONEST) and 4- and 2-O-oleoyl-1,6-anhydroglucopyranose (MONOLE), CMC was higher than 60 mM and IFTmin of 141 mN m−1 and 102 mN m−1, respectively. Promising data were obtained for minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of MONLAU against Staphylococcus aureus strains at 0.25 mM.

Ipase-catalyzed transesterification of LG under continuous flow conditions.  相似文献   
1000.
The history of the scientific enterprise demonstrates that it has supported gender, identity, and racial inequity. Further, its institutions have allowed discrimination, harassment, and personal harm of racialized persons and women. This has resulted in a suboptimal and demographically narrow research and innovation system, a concomitant limited lens on research agendas, and less effective knowledge translation between science and society. We argue that, to reverse this situation, the scientific community must reexamine its values and then collectively embark upon a moonshot-level new agenda for equity. This new agenda should be based upon the foundational value that scientific research and technological innovation should be prefaced upon progress toward a better world for all of society and that the process of how we conduct research is just as important as the results of research. Such an agenda will attract individuals who have been historically excluded from participation in science, but we will need to engage in substantial work to overcome the longstanding obstacles to their full participation. We highlight the need to implement this new agenda via a coordinated systems approach, recognizing the mutually reinforcing feedback dynamics among all science system components and aligning our equity efforts across them.  相似文献   
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