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61.
Atherosclerosis is by far the leading cause of mortality and morbidity in patients with end stage renal disease undergoing chronic hemodialysis (HD). Vascular endothelial cell adhesion molecules like the intercellular adhesion molecule-1 (ICAM-1) and the vascular cell adhesion molecule-1 (VCAM-1) are involved in the pathogenesis of atherosclerosis. Their soluble forms (sICAM-1, sVCAM-1) are considered potential serum markers of endothelial activation and atherosclerosis. The aim of this study was to clarify the influence of the HD procedure on the levels of sICAM-1 and sVCAM-1 in patients with end stage renal disease. We evaluated 35 clinically stable patients (18 males, 17 females, mean age 61 +/- 12) on chronic HD treatment. Diabetes mellitus coexisted in eight patients and arterial hypertension in 23 patients. Blood was drawn before, every hour during, and after a single HD session in each patient. Low-flux cuprophane dialyzers (GFS 12, Gambro, Lund, Sweden) were used in 22 and high-flux polysulfone dialyzers (Hemoflow F 60S, Fresenius, Oberursel, Germany) in 13 cases. At 30 min into the HD session (n=31, 20 low-flux HD, 11 high-flux HD) blood was drawn simultaneously from the entrance and the exit line of the dialyzer. From all these samples, serum concentrations of sICAM-1 and sVCAM-1 were determined by commercially available enzyme immunoassays (ELISA, R&D Systems, Minneapolis, USA). Results were corrected according to hemoconcentration, where appropriate. Plasma levels of sVCAM-1 were elevated in patients with end stage renal disease before the beginning of the dialysis session when compared to healthy controls (1449 +/- 497 ng/mL vs. 691 +/- 118 ng/mL). On the contrary, such an elevation was not found in the case of sICAM-1 (231 +/- 58.5 ng/mL vs. 236.4 +/- 96.8 ng/mL in healthy controls). These levels remained stable in all measurements throughout the dialysis procedure. Furthermore, serum sICAM-1 and sVCAM-1 levels remained unaltered after the passage of the dialyzer. The levels of sICAM-1 and sVCAM-1 were not influenced by the existence of diabetes mellitus, hypertension, or by the utilization of biocompatible, high flux dialyzers. Our study confirms that in chronic HD patients serum levels for sVCAM-1 are elevated. The levels of adhesion molecules are not affected by the HD procedure. These findings probably can be attributed to a decreased renal clearance or catabolism of sICAM-1 and sVCAM-1 and to the different sources of the two molecules. Neither coexisting diabetes mellitus nor arterial hypertension influences the circulating levels of these adhesion molecules. The functional role of sVCAM-1 and sICAM-1, the exact renal contribution to their metabolism, and their role as markers of atherosclerosis in chronic renal disease need further evaluation.  相似文献   
62.
Dorsal epidural migration of an extruded disc fragment is an infrequent event, especially in the thoracic spine. An uncommon case involving a 55-year-old man is presented, with a 1-month history of paraparesis and thoracolumbar pain. Magnetic resonance imaging demonstrated a dorsally located, extramedullary mass at the T10-T11 intervertebral level. The lesion was suspected to be a tumor. The patient underwent a T10-T11 laminectomy. Intraoperatively, an encapsulated mass of soft tissue adherent to the dural sac was found. The pathologic diagnosis was inflammatory tissue and disc material. Six months after the operation, the patient remained asymptomatic, and radiologic control showed no residual mass. Although rare, a sequestered disc fragment should be included in the differential diagnosis of an enhancing posterior extramedullary thoracic mass. Preoperative diagnosis of such pathology is difficult because the clinical signs and radiologic images may not entirely exclude other more common thoracic spinal lesions, especially tumors.  相似文献   
63.
The surgical management of patients with neglected developmental dysplasia of the hip (DDH) after the age of 6 years has been the subject of controversy. We present 11 cases (16 hips) of neglected DDH that were treated operatively by means of open reduction and derotational subtrochanteric osteotomy. Patient age ranged between 10 and 17 years (mean, 12 years). Follow-up ranged from 5 to 13 years (mean, 8.7 years). The results have been satisfactory both clinically (evaluated using the modified Harris hip score) and radiographically (evaluated using Severins classification). Our data suggest that neglected DDH cases, not only during early childhood, but also in the periadolescent period, should be considered for surgical treatment.  相似文献   
64.
The authors report on the unusual case of a patient with intracranial hypotension following an incidental durotomy complicated by an extensive but reversible cerebral vasospasm. Despite the dural tear repair and correction of the intracranial hypotension, the vasospasm ran its course. The precise mechanism of the cerebral vasospasm in this patient is unclear.  相似文献   
65.
AIM: To determine the serum levels of c-reactive protein (CRP), transferrin (TRF), a2-macroglobulin (A2M), ceruloplasmin (CER), a1-acid glycoprotein (AAG), pre-albumin (P-ALB) and retinol-binding protein (RBP) in gastric carcinoma patients and to explore their possible correlation with underlying Helicobacter pylori (H pylori) infection. METHODS: We measured the serum levels of CRP, TRF, A2M, CER, AAG, P-ALB, and RBP in 153 preoperative patients (93 males; mean age: 63.1±11.3 years) with non-cardia gastric adenocarcinoma and 19 healthy subjects. RESULTS: The levels of CRP, CER, RBP, and AAG in cancer patients were significantly higher than those in healthy controls (P<0.0001), while no difference was found regarding the TRF, P-ALB, and A2M levels. Cancer patients with H pylori infection had significantly lower RBP values compared to non-infected ones (P<0.0001) and also higher values of CRP and AAG (P=0.09 and P=0.08, respectively). CONCLUSION: High serum levels of CRP, CER and AAG in cancer patients do not seem to be related to H pylori infection. Retinol-binding protein seems to discriminate between infected and non-infected patients with gastric carcinoma. Further studies are needed to explore if it is directly involved in the pathogenesis of the disease or is merely an epiphenomenon.  相似文献   
66.
Malignant myoepithelioma is a rare salivary gland neoplasm that can arise either de novo or within a pre-existing pleomorphic adenoma. We report a case of malignant myoepithelioma arising from a pleomorphic adenoma of the soft palate. A 70-year-old woman presented in our department with a very large tumor of the soft palate. The patient had a history of a pleomorphic adenoma at the same location that was surgically removed 2 years ago. A second operation, with intraoral excision of the tumor was performed. Histological examination of the recurrence revealed a malignant spindle cell neoplasm with an infiltrative growth pattern and a high mitotic rate. Immunohistochemical investigation confirmed the diagnosis of a low-grade carcinoma of myoepithelial origin with free surgical margins. The patient remains free of disease for more than twelve months after the end of treatment.  相似文献   
67.
68.
There are no prospective data on the effect of a multitargeted treatment approach on cardiovascular disease (CVD) risk reduction in nondiabetic patients with metabolic syndrome (MetS). Furthermore, the optimal hypolipidemic drug treatment in these patients remains controversial. In this prospective, randomized, open-label, intention-to-treat, and parallel study, 300 nondiabetic patients with MetS, free of CVD at baseline, were studied for a period of 12 months. Age- and sex-matched subjects without MetS (n = 100) acted as controls. All patients received lifestyle advice and a stepwise-implemented drug treatment of hypertension, impaired fasting glucose, and obesity. For hypolipidemic treatment, the patients were randomly allocated to 3 treatment groups: atorvastatin (n = 100, 20 mg/d), micronized fenofibrate (n = 100, 200 mg/d), and both drugs (n = 100). Clinical and laboratory parameters, including the lipid profile and C-reactive protein (CRP), were assessed at the baseline and at the end of the study. The primary end point was the proportion of patients not having MetS or its component features at the end of the 12-month treatment period. The secondary end points were the difference in 10-year CVD risk (Prospective Cardiovascular Munster risk calculator) and the degree of CRP reduction. By the end of the study, 76% of the patients no longer had MetS, and 46% had only one diagnostic MetS factor. The estimated 10-year (Prospective Cardiovascular Munster) risk of all patients with MetS at baseline was 14.6%. This was reduced in the atorvastatin group to 6.4%, in the fenofibrate group to 9.2%, and in the combination group to 5.5% (P < .0001 for all vs baseline). The 10-year risks of the atorvastatin and combination groups were not different from that of the control group (5.0%). C-reactive protein was significantly reduced in all treatment groups, with the atorvastatin and combination groups having the greatest reduction (65% and 68%, respectively, P < .01 vs the fenofibrate group, 44%). Lipid values were significantly improved in all 3 treatment groups, with those on the combined treatment attaining lipid targets to a greater extent than those in the other 2 groups. A target-driven and intensified intervention aimed at multiple risk factors in nondiabetic patients with MetS substantially offsets its component factors and significantly reduces the estimated CVD risk. The atorvastatin-fenofibrate combination had the most beneficial effect on all lipid parameters and significantly improved their CVD risk status. Atorvastatin and combination treatment were more effective than fenofibrate alone in reducing CRP levels.  相似文献   
69.
70.
Femoral neck nonunion treatment   总被引:6,自引:0,他引:6  
Femoral neck fracture nonunion is a challenging complication for the orthopaedic surgeon. The etiology of nonunion can be complicated and multifactorial. The diagnosis usually is established clearly with clinical and radiographic examinations. There are no clear guidelines for treatment, although multiple factors must be taken into account. Treatment options include refixation, solitary bone grafting, osteotomy (with and without bone grafting), and prosthetic arthroplasty. The relative indications, shortcomings, contraindications, and results of these different forms of treatment are discussed.  相似文献   
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