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991.
992.
Circular external fixation in tibial nonunions   总被引:2,自引:0,他引:2  
The Ilizarov method based on compression-distraction and subperiostic corticotomy was used in 82 lower extremities. There were 45 tibial nonunions without a significant bone defect and 37 tibial nonunions with a bone defect that required radical removal of the necrotic bone and bone lengthening or bone transport. Bone healing was obtained in 39 of the 45 tibial nonunions without bone defect (mean bone healing, 5.4 months) and in all patients with bone defect (mean bone healing, 15 months for patients treated with bone transport) although secondary surgeries (autografting and tibial nails) were frequent (23 patients). Infection was eradicated in all patients after necrotic bone removal and bone transport. The final mean limb length discrepancy was 0.7 cm for the patients without a bone defect and 2.03 cm for the patients with a bone defect. In the patients in the bone transport group, residual axial deviation and residual limb shortening were common. Circular external fixation is a useful method to solve complex tibial nonunions in patients in whom internal devices and autografting have failed. Patients must be cooperative, and must understand the length of time the frame needs to be worn, and that complications are a probability.  相似文献   
993.
BACKGROUND: Bone loss occurs during the first 6 months after renal transplantation (RT), and corticosteroid therapy plays an important role. Although calcium plus vitamin D administration prevents corticosteroid-induced osteoporosis, its use in RT recipients is limited by the risk of hypercalcemia. METHODS: This double-blind, randomized, and controlled prospective intervention trial examined the effect of intermittent calcitriol (0.5 microg/48 h) during the first 3 months after RT, plus oral calcium supplementation (0.5 g/day) during 1 year with calcium supplementation alone. The primary outcome measure was the change in bone mineral density (BMD) at 3 and 12 months after RT; we also explored whether the effect of calcitriol on BMD was different among vitamin D receptor (VDR) genotypes (BsmI). Forty-five recipients were randomized to calcitriol therapy (CT) and 41 were randomized to placebo (PL). RESULTS: Both groups had a similar degree of pre-existing hyperparathyroidism (197 +/- 229 vs. 191 +/- 183 pg/mL), but a more pronounced decrease of parathyroid hormone (PTH) levels after RT was observed in CT patients (at 3 months: 61.4 +/- 42.2 vs. 85.7 +/- 53.1 pg/mL, P= 0.02; at 12 months: 67.3 +/- 33.7 vs. 82.6 +/- 37 pg/mL; P= 0.08). CT patients preserved their BMD at the total hip significantly better than those on PL (3 months: 0.04 +/- 3.3 vs. -1.93 +/- 3.2%, P= 0.01; 12 months: 0.32 +/- 4.8 vs. -2.17 +/- 4.4%, P= 0.03); significant differences were noted at the intertrochanter, trochanter, and Ward's triangle. Differences did not reach significance at the femoral neck. Two CT patients (4.4%) and 4 PL patients (9.8%) developed a hypercalcemic episode during the first 3 months after RT. The effect of CT on BMD at 3 months was more prominent in recipients with the at-risk allele of the VDR gene (P= 0.03). CONCLUSION: Therapy with low-dose calcium supplements during 1 year, plus intermittent calcitriol for 3 months after RT, is safe, decreases PTH levels more rapidly, and prevents bone loss at the proximal femur; a more pronounced effect is seen in recipients with at least one at-risk allele of the VDR genotype.  相似文献   
994.
BACKGROUND AND OBJECTIVES: Low-intensity laser therapy (LILT) has been studied in many fields of dentistry, but to our knowledge, this is the first time that its effects on orthodontic movement velocity in humans are investigated. STUDY DESIGN/PATIENTS AND METHODS: Eleven patients were recruited for this 2-month study. One half of the upper arcade was considered control group (CG) and received mechanical activation of the canine teeth every 30 days. The opposite half received the same mechanical activation and was also irradiated with a diode laser emitting light at 780 nm, during 10 seconds at 20 mW, 5 J/cm2, on 4 days of each month. Data of the biometrical progress of both groups were statistically compared. RESULTS: All patients showed significant higher acceleration of the retraction of canines on the side treated with LILT when compared to the control. CONCLUSIONS: Our findings suggest that LILT does accelerate human teeth movement and could therefore considerably shorten the whole treatment duration.  相似文献   
995.
AIM: To assess degree of development and level of acceptance of laparoscopic surgery in Spain. METHOD: A questionnaire was sent to all members of the Spanish Association of Surgeons in April 2003. It included 32 questions, 9 of which were general, and 23 referred to specific clinical situations, techniques, and standard practice. RESULTS: Eight hundred and fifty-eight (33.1%) surgeons replied. Only 211 (25%) surgeons reported performing advanced laparoscopic procedures. Four hundred and twenty (49%) surgeons believed that the results obtained with laparoscopic surgery were better than those obtained with conventional surgery, and 325 (40%) surgeons believed that laparoscopy would become a superspecialty. Laparoscopic surgery was considered the method of choice in the treatment of gallbladder stones (99%), gastroesophageal reflux disease (94%), acute cholecystitis (81%), in selected cases of inguinal hernia repair, and in procedures to be performed in spleen and adrenals, benign colon disease, and obesity. Three hundred and ninety-eight (47%) surgeons considered laparoscopic surgery the preferred approach for colon cancer, 292 (34%) for appendicitis, and 155 (18%) for incisional hernia. Five hundred and five (59%) surgeons considered that the use of laparoscopic surgery had grown less than expected. CONCLUSIONS: The vast majority of surgeons advocated laparoscopic surgery for the treatment of gallbladder stones and gastroesophageal reflux disease. Although most hospitals had the appropriate technical facilities for performing advanced laparoscopic procedures, few surgeons actually did so.  相似文献   
996.
Treatment of hepatic echinococcosis remains a surgical problem not only in endemic countries. Between January 1983 and December 1999 a total of 29 patients underwent surgical treatment for hepatic hydatidosis at the Department of General Surgery at the University Hospital of Granada. The diagnosis was based on clinical criteria, serology, and imaging techniques. There were 16 male and 12 female patients (ages 7–67 and 30–74 years, respectively). Concomitant extrahepatic complications were found in seven patients. Among them, five had secondary parasitic cysts in the peritoneal cavity. In one case an intrathoracic rupture was found, and one patient suffered an intraabdominal rupture with anaphylactic shock. The right lobe was affected in 62% (18 patients). Hepatic cysts were multiple in 4 cases and calcified in 13. Conservative surgical procedures were performed in 23 patients (closed marsupialization with fibrin glue obliteration in 17 and drainage-marsupialization in 6), and radical surgical procedures were undertaken in 6 (pericystectomy in 5 and hemihepatectomy in 1). One patient underwent an explorative laparotomy with intraabdominal lavage followed by pericystectomy after primary resuscitation due to anaphylactic shock. The mean period of hospitalization was 15.9 days, and there were no serious postoperative complications or fatal outcomes. The perioperative morbidity rate was 2.5%. One patient suffered a recurrence of the disease following drainage marsupialization after an interval of 5 years. Our results indicate that the closed marsupialization technique is a safe, sparing method for treating uncomplicated hepatic hydatidosis. The results were also compared to those of a former study reported by our group in which the experience of another 19 years was presented.  相似文献   
997.
998.
Sola A  De Oca J  Alfaro V  Xaus C  Jaurrieta E  Hotter G 《Surgery》2004,135(5):518-526
BACKGROUND: We assessed the effect of adding exogenous fructose-1,6-biphosphate (F16BP) to the preservation solution (University of Wisconsin storage solution) used during an experimental procedure of small bowel transplantation in rats. METHODS: We studied levels of the nucleotides hypoxanthine/xanthine and adenosine in tissue after cold ischemia, as well as histologic changes and associated deleterious processes such as bacterial translocation produced by the reperfusion associated with the transplantation. RESULTS: The groups of rats treated with F16BP showed the lowest levels of hypoxanthine/xanthine and uric acid, the highest levels of adenosine, and the lowest levels of histologic damage and lactate dehydrogenase release to the bloodstream. Consumption of intestinal hypoxanthine during reperfusion was lowest in the groups treated with F16BP, as was the incidence of bacterial translocation. CONCLUSIONS: This study shows a protective effect of exogenous F16BP added to University of Wisconsin solution during experimental intestinal transplantation in rats. This protective effect, reflected by decreased intestinal damage and bacterial translocation, was related to a decrease in adenosine triphosphate depletion during cold ischemia before intestinal transplantation, and to the reduced availability of xanthine oxidase substrates for free radical generation during reperfusion.  相似文献   
999.
1000.
PURPOSE: While systematic 12-core (S12C) biopsy detects more cancers than sextant biopsy, to our knowledge the clinical significance of these additionally detected tumors has not been established. We studied pathological parameters of prostatectomy specimens from patients undergoing radical prostatectomy for prostate cancer detected with a S12C biopsy to determine the clinical significance of these cancers in comparison with sextant detected cancers. MATERIALS AND METHODS: A total of 179 consecutive patients undergoing radical prostatectomy for clinically localized prostate cancer detected by S12C biopsy were studied. The groups compared consisted of the sextant core subset of the S12C and the entire S12C set. Total tumor volume, Gleason score, organ confined status, surgical margin status, seminal vesicle invasion, lymph node involvement, and clinical significance of tumors detected by sextant and by S12C templates were compared. RESULTS: S12C biopsy detected a greater number of cancers scored as moderate (Gleason score 2 to 6) or high (Gleason score 7 or greater) grade, and cancers of all sizes regardless of organ confined status than the sextant cores alone (all p <0.05). S12C biopsy identified a greater number of biologically significant and insignificant tumors regardless of how they were defined. CONCLUSIONS: Compared with the sextant set S12C biopsy detects a significantly greater number of surgically curable, biologically significant tumors as well as those that might be considered clinically insignificant.  相似文献   
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