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991.
Introduction  Both fractures of the lumbar spine and at the thoracolumbar junction are quite common. The treatment of these fracture types is discussed controversially. Some authors advocate surgical treatment even in fractures without neurologic compromise while other series report good results after non-operative treatment. Materials and methods  Between January 1997 and April 2004, 324 patients with spinal fractures were admitted to our institution. Hundred and thirty-six patients with compression and burst type fractures treated by closed reduction and casting were available for follow-up. Their medical records, radiographs and computer tomography scans were reviewed and their functional status was assessed. Results  94 male (69.1%) and 42 female (30.9%) patients with a mean age of 48.6 years (range 17–81) at time of injury were included. The thoracolumbar junction (T11-L1) was affected in 104 patients (76.5%). 23.5% had lumbar fractures. All of the burst type fractures with involvement of the posterior column affection were type A3.3. fractures according to the Magerl classification. Significant correction of radiographic parameters was achieved in the early postreduction period (P < 0.0001). Reduction could not be maintained at the final follow-up but still showed slight improvement compared to the initial presentation. Reduction could be maintained better in the thoracolumbar region than in the lumbar spine. Neurologic function was restored in all patients with unilateral radicular pain but only one patient recovered fully after cauda equina-syndrome. Patients after lumbar spine indicated a higher level of pain when compared to patients with fractures at the thoracolumbar junction. Discussion  Closed reduction and casting is a safe and effective method for treatment of compression and burst type fractures at the thoracolumbar junction and can restore neurologic function in patients with unilateral radicular pain. It is of limited value in lumbar fractures and in burst type fractures with posterior column involvement.  相似文献   
992.
The authors report a case of separation involving the posterior aspect of the lateral femoral condyle in a 13-year-old boy. The patient presented with a 2-year history of vague knee discomfort and recurrent knee effusions in the absence of a single acute traumatic event. A large mobile osteochondral fragment involving most of the posterior aspect of the lateral condyle was refixed surgically with two screws via a posterolateral arthrotomy. The knee has recovered full function and the lesion is radiologically stable.  相似文献   
993.
Simultaneous coexistence of Chilaiditi syndrome along with eventration of the diaphragm is a rare occurrence. We present a case of this rare occurrence in a 41 year old male patient who presented with respiratory distress.  相似文献   
994.
111In-oxine-labelled platelet heart scintigraphy (In-plt) was used to evaluate the activity of left atrial thrombi detected by transoesophageal echocardiography (TEE) in 16 cases of rheumatic heart disease. The effect of anticoagulants on the therapeutic intervention of these patients was evaluated by In-plt and TEE. In-plt was performed in all patients in serial pre- and post-anticoagulant therapy studies with anterior, 45 degrees left anterior oblique and left lateral views taken daily from the second to sixth day after injection of labelled platelets. After discontinuing anticoagulants for at least 1 week, only nine cases of left atrial thrombi were detected among the 16 cases by initial In-plt. After anticoagulants were again used for at least 3 weeks, all nine positive cases became negative on repeat In-plt. These results suggest that the diagnostic sensitivity of In-plt is lower than that of TEE. However, In-plt is more suitable and useful for evaluating the activity of left atrial thrombi after antithrombotic agent therapy and for monitoring the effect of anticoagulant therapy on left atrial thrombi in patients with rheumatic heart disease.  相似文献   
995.
PURPOSE: Our goal was to determine whether dynamic MR subtraction images could be used to detect and stage gastric tumors. METHOD: Dynamic MR subtraction images were prospectively performed in 20 patients without gastric lesions and in 39 patients with gastric tumors. The flat- or depressed-type early gastric cancers were excluded. The MR findings were assessed for layered pattern of the normal gastric wall, detectability of tumors, enhanced pattern of tumor, and depth of the tumor invasion. Surgical specimens were obtained from 30 of the patients with tumors, and histopathologic sections were made in the dynamic MR scanning direction. RESULTS: The three-layered structure of the normal gastric wall was apparent in more of the dynamic MR subtraction images (60%) than of the nonsubtraction images (30%) in the control group. All 39 gastric tumors were detected by MRI. The intact inner layers overlying stromal tumors and outer layers interrupted by advanced gastric cancers were clear on the subtracted images. MRI accurately T-staged 88% of the gastric cancers. CONCLUSION: Dynamic MR subtraction images can be used to identify gastric tumors and to stage gastric cancers.  相似文献   
996.
A variable-density k-space sampling method is proposed to reduce aliasing artifacts in MR images. Because most of the energy of an image is concentrated around the k-space center, aliasing artifacts will contain mostly low-frequency components if the k-space is uniformly undersampled. On the other hand, because the outer k-space region contains little energy, undersampling that region will not contribute severe aliasing artifacts. Therefore, a variable-density trajectory may sufficiently sample the central k-space region to reduce low-frequency aliasing artifacts and may undersample the outer k-space region to reduce scan time and to increase resolution. In this paper, the variable-density sampling method was implemented for both spiral imaging and two-dimensional Fourier transform (2DFT) imaging. Simulations, phantom images and in vivo cardiac images show that this method can significantly reduce the total energy of aliasing artifacts. In general, this method can be applied to all types of k-space sampling trajectories.  相似文献   
997.
The current guidelines recommend a dosage of prednisone of 60 mg/m2 body surface area per day (BSA PRED) for the initial therapy of nephrotic syndrome (NS). Alternatively, a dosage of 2 mg/kg body weight per day (W PRED) can be used. We hypothesized that the BSA PRED and W PRED are not equivalent and analyzed the differences between BSA PRED calculated with various formulas for body surface area (BSA), W PRED and the dose of prednisone prescribed for our patients. We performed a retrospective chart review of the patients at their initial presentation of NS. Thirty-three children were included, of median age 3.34 years at presentation. The W PRED was significantly lower than BSA PRED (P < 0.05), with a median W PRED:BSA PRED ratio of 0.85 [interquartile range (IQR) 0.8 to 0.9]. The difference between W PRED and BSA PRED decreased proportionally to patients’ weights up to 30 kg. No differences were noted between the various BSA formulas using both weight and height for the calculation of BSA. The Bland–Altman analysis showed a proportional error between W PRED and BSA PRED up to the average daily dose of 60 mg, with a mean bias of 0.86 (95% limits of agreement = 0.68 to 1.05). Ten out of the 33 patients (30%) were given a lower than recommended BSA PRED dose by more than 5 mg/day. In conclusion, the dosage of prednisone at 2 mg/kg per day versus 60 mg/m2 per day is not equivalent for patients with weights <30 kg and/or dose <60 mg/day.  相似文献   
998.
999.
We have carried out a study with the aim of investigating the association between single nucleotide polymorphisms (SNPs) of the IL-1 gene cluster and childhood IgA nephropathy (IgAN). SNPs of the IL-1α, IL-1β, and IL-1 receptor antagonist (RN) genes (IL1A, IL1B, and IL1RN, respectively) were analyzed in 182 patients with childhood IgAN and in 500 healthy controls. The IgAN patients were also dichotomized and compared with respect to proteinuria (<4 mg and ≥4 mg/m2 per hour, respectively), the presence or absence of podocyte foot process effacement, and the presence of pathologically early and advanced disease markers, such as interstitial fibrosis, tubular atrophy, or global sclerosis. Significant differences in SNP frequencies were observed for the IL1B and IL1RN genes (rs1143627, rs3917356, and rs1143633 in the IL1B gene, and rs928940, rs439154, and rs315951 in the IL1RN gene). Moreover, rs1143627, rs3917356, and rs1143633 of IL1B were found to be significantly associated with the presence of podocyte foot process effacement. Our results suggest that the IL1B and IL1RN genes are associated with increased susceptibility to IgAN in children. They also suggest that the development of proteinuria in IgAN is related to IL1A and that podocyte foot process effacement is associated with IL1B.  相似文献   
1000.
Background  It is generally believed that the accompanying conditions in patients with inflammatory bowel disease (IBD) are associated with a high incidence of surgical site infection (SSI), and sometimes these patients are classified as compromised hosts without definitive clinical evidence. The aim of this study was to clarify the impact of IBD on the occurrence and features of SSI in patients with clean-contaminated wounds. Methods  We conducted prospective SSI surveillance of 580 patients with clean-contaminated wounds who underwent surgery between March 2006 and December 2007 using the National Nosocomial Infection Surveillance system. Multivariate analyses using stepwise logistic regression were performed to determine risk factors for SSI. Results  A total of 562 patients with clean-contaminated wounds who underwent surgery for IBD [ulcerative colitis (UC), n = 173; Crohn’s disease (CD), n = 122] or colorectal cancer [(CA), n = 267] were identified for evaluation. SSI was observed in 12.6% of all patients and there was no significant difference in infection rate by type of disease (UC, 14.5%; CD, 13.9%; CA, 10.9%). Multivariate logistic regression analysis yielded an ASA score ≥3 [odds ratio (OR) = 2.04; 95% confidence interval (CI) = 1.06–3.93] and rectal surgery (OR = 2.35; 95% CI = 1.28–4.31) as independent risk factors for SSI. IBD surgery was not an independent risk factor for overall SSI (OR = 1.62; 95% CI = 0.94–2.80). However, there was a significant difference in the incidence of incisional SSI [IBD, 11.9% (UC, 12.7%; CD, 10.7%); CA, 4.9%, p = 0.003]. In the analysis of rectal surgery, the incidence of incisional SSI was 5.3% in CA patients, 12.0% in UC patients, and 26.3% in CD patients. In contrast to overall SSI data, IBD surgery was found to be an independent risk factor for incisional SSI (OR = 2.59; 95% CI = 1.34–5.03). Conclusions  In patients of surgery restricted to clean-contaminated wounds, IBD was shown to be an independent risk factor for incisional SSI. With the use of proper operative procedures and techniques, the incidence of organ/space SSI should not be high in patients who undergo an uncomplicated IBD surgical procedure.  相似文献   
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