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131.
The authors investigated the prevalence and the difference in the severity of systemic complications following intramedullary nailing of bilateral tibial and femoral shaft fractures. A retrospective chart analysis of 12 consecutive patients with bilateral tibial shaft fractures (TF) and 14 patients with bilateral femoral shaft fractures (FF) was performed. The incidences of bilateral tibial fractures and bilateral femoral shaft fractures were 3.8% and 4.6% respectively. The median Injury Severity Score (ISS) in TF group was 13 (9-29) compared to 16 (9-34) in the FF group (p = 0.169). The mean resuscitation requirements were 4.2 (3-11) litres of colloids and crystalloids and 1.7 (0-10) units of blood in the TF group and 10.6 (6-16) litres of colloids and crystalloids and 9.2 (5-25) units of blood in the FF group (p = 0.002). In the TF group there was 1 death compared to 2 in the FF group. In the TF group, there were 2 cases of ARDS, 4 cases of deep sepsis and 3 above knee amputations. In the FF group, there were 6 cases of ARDS (p = 0.04), 1 case of deep sepsis and 1 above knee amputation. Patients with bilateral tibial shaft fractures revealed lower ISS, resuscitation requirements, ARDS, associated injuries, and mortality when compared to bilateral femoral shaft fractures. This is probably due to the anatomical difference in the morphology of the bones, volume of liberated intravascular marrow fat, organisation and layout of the venous capillary network and severity of associated injuries.  相似文献   
132.
PURPOSE: To assess the utility of magnetic resonance cholangiopancreatography (MRCP) in preoperative mapping of biliary anatomy in adult-to-adult living related liver transplant (LRLT) donors. MATERIALS AND METHODS: From 57 potential donors with preoperative MRCP, 27 cases (16 men, 11 women, age range 22-51 years, mean 37.2 years) underwent right lobe resection and had intraoperative cholangiography (IOC) for comparison. The MRCP and IOC reports were retrospectively reviewed in all 27 cases. The MRCP was performed on 1.5 Tesla MR magnets using breath-hold heavily T2-weighted sequences in axial/coronal thin sections, and variable-thickness rotating slabs. The accuracy of preoperative MRCP for biliary mapping in potential LRLT donors was analyzed compared to the IOC findings. RESULTS: Of 27 donors, 26 (96.3%) had MRCP which showed adequate information of central intrahepatic biliary anatomy. Of these, 19 had normal bifurcation confirmed by IOC, and single biliary anastomosis was created in the recipient at transplantation. MRCP correctly predicted 17 of 19 normal cases (sensitivity for normals: 89.5%). In seven donors with variant biliary anatomy, two separate biliary anastomoses were performed in the recipient. MRCP correctly predicted five of seven variants (sensitivity for variants: 71.4%). Overall, MRCP had an accuracy 84.6% (22/26). CONCLUSIONS: MRCP has potential in the preoperative assessment of nondilated bile ducts in LRLT donors, however further improvements are desired to increase its quality and accuracy.  相似文献   
133.
OBJECTIVE: The purpose of our study was to determine whether intraperitoneal insufflation of carbon dioxide (CO(2)) reduces adjacent diaphragmatic injury. MATERIALS AND METHODS: In seven pigs under anesthesia, a 17-gauge percutaneous insufflation needle was inserted in the infraumbilical midline using a standard insufflator. Three to six liters of CO(2) was infused into the peritoneal space to achieve at least a 1-cm separation between the liver and the diaphragm and maintained by a pressure of 8-10 mm Hg. Seven control lesions in six historical controls were used. In addition, five lesions were created in one animal from this cohort who served as a control. Superficial areas of liver separated from diaphragm were fluoroscopically targeted for radiofrequency ablation, and several 2-cm-diameter radiofrequency lesions were generated. The pigs were sacrificed at 48 hr, and at laparotomy, the liver surface was inspected and sectioned to select lesions with centers within 1 cm of the surface. The thermal injury to the corresponding adjacent diaphragm was examined to determine the depth of injury. Diaphragmatic injury was graded on a scale from 0 to III (0, no injury; I, mild injury to one-third thickness; II, moderate injury to two-thirds thickness; III, severe injury to full thickness.) RESULTS: Of 72 total lesions created, 60 had centers less than 1 cm from the liver surface (i.e., superficial) at laparotomy. Of these 60 lesions, 55 caused no significant diaphragmatic injury, two caused grade I injury and three caused grade III injury. In comparison, seven of seven historic superficial control lesions and five of five superficial radiofrequency control lesions from the current cohort caused grade III injury. Superficial radiofrequency lesions created after intraperitoneal CO(2) insufflation caused significantly less (p < 0.01) diaphragmatic injury. CONCLUSION: We have shown that in pigs, intraperitoneal CO(2) insufflation helped significantly reduce severe diaphragmatic injury when superficial hepatic radiofrequency ablation was performed.  相似文献   
134.
135.
The authors describe a novel way of fashioning an endoscope holder from a common retractor and an ear speculum. Using such a device during endoscopic sinus surgery leaves both of the surgeon's hands free to manipulate the instruments.  相似文献   
136.
137.
The purpose of this study was to characterize the pharmacokinetic parameters of mycophenolic acid (MPA) in Korean kidney transplant recipients. Plasma MPA concentrations of 10 Korean kidney transplant recipients administered a lower dose of mycophenolate mofetil (MMF; 750 mg twice a day) were measured at 2 weeks of MMF therapy by high-performance liquid chromatography (HPLC). The plasma MPA concentration-time curve pattern of patients taking lower doses of MPA was consistent with previously reported profiles of patients taking the fully recommended doses. The plasma MPA concentration-time curve was characterized by an early sharp peak within 1 hour and a small second peak in some patients at 4 to 12 hours postdose. The mean C(max) and AUC were 8.73 +/- 4.65 microg/mL and 18.45 +/- 4.25 microg*h/mL, respectively. The mean fraction of free MPA was 1.60% +/- 0.23%. Patients' age, weight, body surface area, and renal function did not influence the AUC. The free fraction of MPA appeared not to be affected by serum albumin and renal function when creatinine clearance was above 40 mL/min. Regression analysis between each plasma concentration and AUC for the limited sampling strategy of MMF therapeutic drug monitoring demonstrated that the concentrations of predose and 1- and 8-hour postdose were positively correlated with AUC (r = 0.74545, p = 0.0133; r = 0.68485, p = 0.0289; and r = 0.63636, p = 0.0479, respectively). The pattern of the concentration-time profile of MPA in Korean kidney recipients was similar to the results of other studies performed in Caucasians, although there was interindividual variability of AUC, C(max), and t(max). MPA concentrations of predose and 1- and 8-hour postdose were positively correlated with AUC.  相似文献   
138.
RNA and protein gene expression technologies are revolutionizing our view and understanding of human diseases and enable us to analyze the concurrent expression patterns of large numbers of genes. These new technologies allow simultaneous study of thousands of genes and their changes in regulation and modulation patterns in relation to disease state, time, and tissue specificity. This review summarizes the application of this modern technology to four common neurological and psychiatric disorders: HIV-1-associated dementia, Alzheimer's disease, multiple sclerosis, and schizophrenia and is a first comparison of these diseases using this approach.  相似文献   
139.
PURPOSE: To assess degree of macrovesicular steatosis with unenhanced computed tomography (CT) and correlate it with histologic findings in potential donors for living related liver transplantation. MATERIALS AND METHODS: Forty-two candidates underwent unenhanced CT within 4 weeks of core liver biopsy. An experienced liver pathologist, blinded to both CT and surgical findings, retrospectively reviewed biopsy specimens and determined degree of macrovesicular steatosis. A radiologist blinded to histologic grading calculated mean hepatic attenuation in each donor liver by averaging 25 region-of-interest (ROI) measurements on five sections (five ROIs per section). Mean splenic attenuation was calculated with three separate ROI measurements. Liver attenuation index (LAI) was derived and defined as the difference between mean hepatic and mean splenic attenuation. Body mass index (BMI) was determined for each patient. Linear regression analysis was used to correlate degree of macrovesicular steatosis with both LAI and BMI. RESULTS: LAI correctly predicted degree of macrovesicular steatosis in 38 (90%) of 42 cases. In four of four livers, LAI below -10 HU correlated with greater than 30% macrovesicular steatosis (unacceptable for liver transplantation). In nine of 11 livers, LAI was between -10 and 5 HU and correctly predicted 6%-30% steatosis (relative contraindication). In two of 11 cases, LAI overestimated degree of hepatic steatosis. LAI above 5 HU correctly predicted 0%-5% steatosis in 25 of 27 livers. In two of 27 cases, parenchymal hemosiderin deposition led to an increase in LAI into the normal range, despite mild histologically confirmed steatosis. Degree of histologic macrovesicular steatosis correlated well with LAI (r = 0.92) and marginally with BMI (r = 0.45). Of 27 potential donors with normal livers at CT and acceptable LAI levels, four (15%) were deemed poor donor candidates because core biopsy revealed subtle hepatic necrosis and nonspecific hepatitis. CONCLUSION: Although unenhanced CT quantifies the degree of macrovesicular steatosis relatively well, it may preclude a liver biopsy only in a small percentage of potential donors with low LAI (unacceptable degree of steatosis). Core liver biopsy is still necessary in the majority of donors with normal LAI to identify those with both fatty liver and coexistent hemosiderin deposition or radiologically occult diffuse liver diseases.  相似文献   
140.
BACKGROUND: There is a paucity of work in the literature examining the long-term visual prognosis of patients with choroidal ruptures. We performed a study to get a better assessment of long-term visual recovery in these patients as well as to identify prognostic indicators. METHODS: We reviewed the charts of 32 patients who experienced traumatic choroidal rupture following blunt ocular trauma. All charts contained International Classification of Diseases code 363.63 (choroidal rupture). For inclusion in the study, the chart had to contain detailed drawings or photographic evidence that could confirm the presence and location (foveal, juxtafoveal or extrafoveal) of the choroidal rupture. In addition, demographic data and visual acuity on follow-up examinations had to be present. The mechanism and location of the injury, initial and final visual acuity, associated ocular findings and length of follow-up were recorded. RESULTS: Of the 32 eyes 31 had indirect choroidal ruptures and I had a direct rupture. The mean final visual acuity values in the foveal, juxtafoveal and extrafoveal subgroups were 20/68, 20/35 and 20/60 respectively after a mean duration of follow-up of 4.5, 3.5 and 4.4 years respectively. There was no statistically significant difference in mean final visual acuity or mean length of follow-up between the three groups. The eight patients with multiple choroidal ruptures had a mean final vision of 20/31 after a mean follow-up period of 3.8 years. The 24 patients with a single choroidal rupture achieved a mean final vision of 20/47 over a mean duration of follow-up of 4.1 years. There was no difference in final vision or in length of follow-up between the two groups. The six patients under 15 years of age attained a mean final vision of 20/34 over a mean follow-up period of 4.5 years, whereas the adult group achieved a mean final vision of 20/44 over a mean follow-up period of 3.8 years. Again, there was no difference in final vision or in length of follow-up between the two groups. INTERPRETATION: Traumatic choroidal rupture involving the fovea has been thought to have a poor visual prognosis. Our findings show that eyes with foveal choroidal ruptures may regain good central vision over longer follow-up. Furthermore, multiple choroidal ruptures do not necessarily predict a poor visual outcome. Children with choroidal ruptures attained good final visual outcomes.  相似文献   
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