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991.
Scoliosis involves the central nervous system diseases, ligaments, articulations and skeletal muscles, but there is no consensus on its pathogeny and progression of muscle abnormalities. In this study, we investigate the morphologic changes in the muscle of rabbit submitted to experimental scoliosis, with special emphasis on abnormalities related to blood supply. We studied 26 rabbits subjected to costotransversectomy by pulling out six transverse processes at thoracic level and six rabbits were used as controls. All the animals operated upon developed scoliosis showing an average angle of 29.1° on the 60th day, with its apices located at T4 and T12 when they were subjected to paraspinal muscle biopsy on both sides. The muscle biopsies were subjected to histological stains and histochemical reactions, as well as to a morphometric study. On the concave side, the changes were not statistically significant regarding the control group. On the convex side conjunctive tissue proliferation, infiltration by adipose tissue, central nucleus excess, inflammatory reaction, segmental fibrosis, type 1 fiber hypertrophy, type 2 fiber hypertrophy and atrophic angular dark fibers in the unspecific esterase were statistically significant. The segmental fibrosis reached a circumscribed muscle segment, compatible with an ischemic phenomenon. The histological diagnoses on the concave side of the animals had unspecific alterations (atrophy and hypertrophy) in 13, myopathy in 3, denervation in 3 and normal in 7. The convex side diagnoses were myopathy in 14, denervation in 8, mixed in 3 and normal in 1. The procedure determined morphologic changes on the convex side indicating possible denervation or myopathy of ischemic origin.  相似文献   
992.
Evaluation of renal function should be performed as part of the follow-up during and after chemotherapy in pediatric cancer patients. The aim of this study was to compare an isotope clearance method [isotope glomerular filtration rate (iGFR)] with alternative methods to determine GFR in such patients. Isotope GFR [99mTc-labeled diethylene triaminopentoacetic acid (DTPA) or 51Cr-labeled ethylenediaminetetra-acetate (EDTA)] was measured in 36 children (112 studies) and compared with simultaneously measured creatinine clearance (CrCl), serum creatinine (SCr), and cystatin C (CysC) concentrations, as well as the results of Schwartz, Counahan–Barratt, and Cockroft–Gault formulae, using general linear mixed models. Our results showed a significant association between iGFR and CysC concentrations (p < 0.001). No linear relationship was observed between CrCl and iGFR (p = 0.7). As expected, the results of height-based formulae (Counahan–Barratt and Schwartz) had significantly (p = 0.004) better correlation to iGFR than the results of a formula based on weight (Cockroft–Gault) (p = 0.19). Despite significant linear correlation, intraclass correlation coefficients showed poor agreement. Tests of similarity between iGFR estimates showed differences between average values of GFR. Therefore, determination of iGFR remains the method of choice in estimation of GFR in cancer patients. In our study population, assay of serum CysC was the most reliable alternative method to measure glomerular function.  相似文献   
993.
First rib pathology can narrow the thoracic outlet thus producing compression of the brachial plexus and subclavian vessels. There have been only three case reports of neurogenic thoracic outlet syndrome (TOS) caused by a nonunion of the first rib and there have been no reports of a first rib malunion causing TOS. A rare case of TOS caused by a malunion of the first rib is presented. This work has not received financial support and the authors declare no conflict of interest.  相似文献   
994.
Since the first reports with laparoscopic resection of islet cell tumors in 1996, the experience worldwide is still limited, with only short-term outcomes available. Some have suggested that a malignant tumor is a contraindication to laparoscopic resection. Aim The aim of this study was to evaluate the feasibility, safety, and long-term outcome of the laparoscopic approach in patients with functioning, nonfunctioning, or overt malignant pancreatic neuroendocrine tumor (PNT). To our knowledge this is the largest single-institution series on this subject to date. Patients and methods A total of 49 consecutive patients (43 women, 6 men; mean age 58 years, range 22–83 years) underwent laparoscopic pancreatic surgery (LPS) from April 1998 to June 2007. Preoperative localization was done by computed tomography, magnetic resonance imaging, endoscopic ultrasonography, and Octreoscan imaging. Other than 9 PNTs localized in the head of the pancreas, all tumors were located in the left pancreas. Malignancy was diagnosed based on the presence of lymph nodes or liver metastasis. There were 33 patients with functioning tumors: 4 with gastrinomas (mean size 1.2 cm), 1 with a glucagonoma (4 cm), 3 with vipomas (3.2 cm), 2 with carcinoids (5.2 cm), 20 with sporadic insulinomas (1.4 cm), 2 with insulinoma/multiple endocrine neoplasia type 1 (MEN-1) (4.4 cm), and 1 with a malignant insulinoma (13 cm). Sixteen patients had a nonfunctioning tumor (mean size 5 cm). The following techniques were performed: laparoscopic spleen-preserving distal pancreatectomy (Lap SPDP), laparoscopic distal pancreatectomy with splenectomy (Lap SxDP) and laparoscopic enucleation (Lap En)/laparoscopic excision (Lap E). Lymph node dissection was performed when malignancy was suspected (Strasberg′s technique). Evaluation criteria included operative and postoperative factors, pathologic data including R0 or R1 resection (the pancreatic transection margin and all transection margins on the specimen were inked). Long-term outcomes were analyzed by tumor recurrence and patient survival. Results Four cases (8.2%) were converted to open surgery. Overall, Lap SPDP, Lap SxDP, and Lap En/Lap E were performed in 15 (33.3%), 8 (17.8%), and 22 (48.9%) patients, respectively. The operative time and blood loss was significantly lower in the Lap En group compared with the other laparoscopic techniques. The group of patients with malignant tumors undergoing Lap SxDP had a longer operating time and greater blood loss compared with the other distal pancreatectomy (Lap DP) techniques. Overall, the postoperative complications were significantly higher in the Lap En group (42.8%) than in the Lap DP (Lap SPDP + Lap SxDP) group (22%). These complications were mainly pancreatic fistula: 8.7% after Lap DP and 38% after Lap En. The overall morbidity was significantly higher after Lap SPDP (26.7%) than after Lap SxDP (12.5%) owing to the occurrence of splenic complications in the Lap SPDP group without splenic vessel preservation two of seven (28.5%). The means and ranges of hospital stay after Lap SPDP, Lap SxDP, and Lap En/Lap E were 5.9 (5–14), 7.5 (5–12), and 5.5 (5–7) days, respectively (NS). Pathology examination of the specimen showed R0 resection in all patients with malignant PNT. The mean time to resumption of previous activities for patients undergoing Lap DP or Lap En was 3 weeks. There were no postoperative (30 days) or hospital deaths. Conclusions This series demonstrates that LPS is feasible and safe in benign-appearing and malignant neuroendocrine pancreatic tumors (NEPTs). The benefits of minimally invasive surgery were manifest in the short hospital stay and acceptable pancreas-related complications in high-risk patients. LPS can achieve negative tangential margins in a high percentage of patients with malignant tumors. Although surgical cure is rare in malignant NEPTs, significant long-term palliation can be achieved in a large proportion of patients with an aggressive surgical approach.  相似文献   
995.
Type 1 diabetes mellitus (T1DM) commonly occurs in childhood or adolescence, although the rising prevalence of type 2 diabetes mellitus (T2DM) in these age groups is now being seen worldwide. Diabetic nephropathy (DN) develops in 15–20% of subjects with T1DM and in similar or higher percentage of T2DM patients, causing increased morbidity and premature mortality. Although overt DN or kidney failure caused by either type of diabetes are very uncommon during childhood or adolescence, diabetic kidney disease in susceptible patients almost certainly begins soon after disease onset and may accelerate during adolescence, leading to microalbuminuria or incipient DN. Therefore, all diabetics warrant ongoing assessment of kidney function and screening for the earliest manifestations of renal injury. Pediatric health care professionals ought to understand about risk factors, strategy for prevention, method for screening, and treatment of early DN. This review considers each form of diabetes separately, including natural history, risk factors for development, screening for early manifestations, and strategy recommended for prevention and treatment of DN in children and adolescents.  相似文献   
996.
Mesangial hypercellularity (MH), in the absence of sclerosis or immune deposition, was a common finding on renal biopsy in our center. We studied 66 children with predominant MH. Among all patients older than 2.7 years, blood pressure (BP) percentile and glomerular filtration rate (GFR) remained stable. Serum albumin (Alb) trended higher (3.0 ± 0.2 start vs. 3.4 ± 0.2 end g/dl, p = 0.06) and urine protein/creatinine lower (4.2 ± 0.9 start vs. 2.3 ± 0.9 end mg/mg, p = 0.18) at the end of the study period. The proportion with stage 1 CKD remained constant: 94% start vs. 92% end. At end, Alb was lower in patients referred for nephrotic syndrome (NS): 4.4 ± 0.3 hematuria vs. 4.2 ± 0.2 proteinuria vs. 2.8 ± 0.3 NS g/dl, p < 0.05 vs. both. Alb was lower (p = 0.03) and urine protein/creatinine trended higher in patients with diffuse foot-process fusion (FPF). Twenty-five percent of patients with focal FPF developed NS, all had relapses, and 63% were steroid sensitive (SS). All but one with diffuse FPF presented with NS; 86% had relapses (mean 1 year) and 63% were SS. GFR trended higher at the end in those with matrix thickening (mat) (119.6 ± 4.7 no mat vs. 129.1 ± 2.6 mat ml/min per 1.73 m2, p = 0.1). Those without mat were less SS (59% no mat vs. 80% mat) and were more likely to require alkylating agents (Alk) for NS. Among those with positive immunofluorescence (IF), 82% had immunoglobulin M (IgM) alone; those with positive IF were more SS and needed Alk for NS. MH predicts a favorable prognosis. FPF predicts NS and multiple relapses.  相似文献   
997.
Early mechanical dysfunction of a total knee arthroplasty (TKA) is a challenging problem in terms of causality and solutions. The current strategy in our department is to perform a complete TKA revision rather than the less invasive partial procedures when a clear mechanical cause of failure has been found. In this investigation, we assessed 21 patients who underwent complete TKA revision in 2003-2004 in our institution within the first two years following the index TKA. Various clinical presentations included pain, stiffness, instability, and femoro-patellar signs. These corresponded to implant size, position, and fixation issues. The IKS knee score/function significantly increased from 47/47 to 85/78 at follow-up (six months minimum). Compared to the data in the literature, this systematic full revision seems to be a reasonable approach. This attitude takes advantage of the modularity of the implants for allowing perioperative adjustments of position, fixation, and constraint. Based on the results of our study, we propose a list of six mechanical pitfalls to be evaluated in the case of early dysfunction: frontal misalignment, sagittal overstuffing or malpositioning, axial malrotation, poor bone fixation, inappropriate constraint or ligamentous balance, and inappropriate level of the joint space.  相似文献   
998.
Objectives In this study, we try to evaluate the efficacy and safety of holmium lasers for treatment of ureteric stones in patients with renal impairment or obstructive anuria. Patients and methods Twenty-six patients were included in this study, of which 20 patients presented with elevated blood urea and serum creatinine (2.1–7.6 mg%), and six patients presented with calcular anuria (mean serum creatinine 22 mg%). None of the patients had a ureteric stent or nephrostomy tube before the ureteroscopy. All patients were treated with holmium laser. A stone basket or grasper was used to remove significant stone fragments at the end of the procedure in seven patients. In these seven patients, ureteric stents were placed at the end of the procedure. Results All patients were free of any stone fragments at 1 week and at 3 months postoperatively. In all patients, including the six with obstructive anuria, the renal impairment resolved or improved as evidenced by normalization or fall in blood urea and creatinine. Thus, in this small group of uremic patients, the success rate for treatment of ureteral stone was 100%. Conclusions A holmium laser is a safe and effective modality of ureteroscopic lithotripsy in patients with significant renal impairment or even obstructive anuria. The use of holmium laser with ureteroscopy may be considered in this group of patients as long as the general condition of the patient permits the safe administration of anesthesia.  相似文献   
999.
Background Endoscopic ultrasound-guided fine-needle aspiration (EUS FNA) has a high accuracy in the evaluation of mediastinal lesions. The use of a core biopsy needle for EUS guided biopsy (EUS TCB) may further improve the yield of EUS. The aims of this study are to evaluate the safety of EUS TCB in thoracic lesions and to compare the diagnostic accuracy of TCB with FNA and FNA + TCB. Methods A single-center retrospective study. All patients underwent EUS-FNA and TCB. A cytopathologist was not present during the procedure. EUS FNA, TCB and FNA + TCB diagnostic accuracy were compared. Results A total of 48 patients were included. The lesions sampled included 41 lymph nodes (six aorto-pulmonary window, 32 subcarinal, two right paratracheal, one paraesophageal ATS station 8), five lung masses, and two esophageal masses. Twenty-nine patients had malignant disease and 19 had benign disorders. The overall diagnostic accuracy of FNA, TCB and FNA + TCB was 79%, 79% and 98% respectively (p = 0.007). TCB changed the diagnosis in nine cases missed by FNA. EUS TCB was better than FNA for benign diseases (89% vs. 63%, p = 0.04). All eight patients with a prior failed biopsy had a correct diagnosis established by EUS. No patient required mediastinoscopy or thoracoscopy after EUS. Conclusion The combination of TCB and FNA is superior to FNA alone. EUS-guided TCB should be considered in patients with benign disorders of the mediastinum when other modalities fail to yield a diagnosis.  相似文献   
1000.
Background Bleeding pelvic fracture patients with severe associated injuries have a high mortality rate that is exacerbated by several factors. To gain deeper etiological insights into this injury, we investigated the specific risk factors associated with the high mortality rate. Methods A total of 102 bleeding pelvic fracture patients with severe associated injuries (abbreviated injury score ≥3) were treated at our level I trauma center between January 1994 and December 2004. Predictors of death within 24 h of arrival were determined by univariate and multivariate analyses using anatomic and physiologic parameters, including injured body part, shock symptoms, age, sex, injury severity score (ISS), and fracture type. Results Overall, 47 of the 102 patients died within 24 h of arrival. Hemorrhage shock was responsible for the majority of deaths (47%). Other causes included central nervous system injury (21%), multiple injuries (central nervous system injury plus shock, 18%) and multiple organ failures (7%). Univariate analyses revealed that patients presenting with head and neck injuries and shock symptoms on arrival were associated with an increased risk of death (P < 0.01 for both variables). Multivariate analyses revealed that these injuries and shock symptoms were independently associated with a higher risk of death (odds ratios of 2.704 and 4.632, respectively). The mechanism of injury, fracture type, age, sex, and ISS were not associated with an increased risk of death. Conclusions Statistically significant risk factors were brain injuries and shock symptoms on arrival. Brain injuries should be heavily weighted when evaluating the prognosis of bleeding pelvic fracture patients.  相似文献   
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