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71.

Purpose

Aneurysmal bone cyst is a benign, relatively uncommon lesion, representing 1.4 % of primary bone tumors. The vertebral column is involved in 3–30 % of cases. This report describes clinical characteristics and treatment results of 18 patients with aneurysmal bone cyst of the spine.

Methods

Between 1991 and 2008, 18 patients with aneurysmal bone cyst of the spine were surgically treated in our department. The clinical records, radiographs, histologic sections, and operative reports were analyzed.

Results

There were 11 male and 7 female patients; mean age was 22.1 years (range 7–46 years). Localizations were cervical (3), cervicothoracic (2), thoracic (3), lumbar (4), and sacrum (6). Tumor was localized on the left side in 11 cases, on the right side in 2 and at midline in 5 patients. The two most common clinical features were axial pain (14 patients) and radicular pain (8 patients). Neurological signs were paraparesis in 3, monoparesis in 6. Mean duration of symptoms was 9 months (range 3 months–3 years). All patients underwent surgery: total removal was performed in 13 patients and subtotal resection in 5. Posterior (11), anterolateral (1), or combined anterior-posterior (6) approaches were used. Mean follow-up duration was 112.3 months (range 4–21 years). We detected four recurrences in subtotal excision group (4/5), and one recurrence in total excision group (1/13).

Conclusion

Treatment options for aneurysmal bone cysts are simple curettage with or without bone grafting, complete excision, embolization, radiation therapy, or a combination of these modalities. Radical surgical excision should be the goal of surgery to decrease the recurrence rate. Recurrence rate is significantly lower in case of total excision.  相似文献   
72.
Posttraumatic spondyloptosis develops as a result of complete subluxation of the vertebral bodies and causes complete transection of the spinal cord. Severe trauma-related spondyloptosis of the upper-mid thoracic region is a rare form of spinal trauma. Traumatic midthoracic spondyloptosis is quite rare, and radiology plays an important role in the diagnosis and treatment of this condition. Surgical reconstruction and stabilization are required for early mobilization and rehabilitation of patients with this injury. Here, we report the clinical features, radiographic findings, and management of an unusual case of traumatic midthoracic spondyloptosis that showed complete spinal cord transection and was operated.  相似文献   
73.
Vascular access thrombosis is a leading cause of vascular access failure in hemodialysis patients. Thrombosis is a multifactorial condition and genetic makeup can affect thrombosis risk. We conducted a study to investigate for possible associations between ecNOS gene intron 4 variable-number tandem repeat (VNTR) polymorphism and thrombosis of polytetrafluoroethylene hemodialysis arteriovenous access grafts (AVG) in Turkish patients. Fifty-five patients with end-stage renal disease who had AVGs implanted between 2000 and 2002 and 167 healthy individuals representing our healthy population were enrolled in this prospective study. Each subject provided a venous blood sample from which DNA was isolated, and polymerase chain reaction analysis was done to identify genotypes (aa, bb, ab) for ecNOS gene intron 4 VNTR polymorphism. All grafts were placed in brachioaxillary position. The subjects were divided into two groups based on duration of graft patency. The thrombosis group (Group I) comprised 26 patients who developed AVG thrombosis in the first 12 months after placement. The no-thrombosis group (Group II) comprised 29 patients whose grafts remained patient for at least 12 months. The frequency of the aa genotype in Group I was significantly higher than that in Group II (p =. 005). At 6, 12, and 24 months, the primary patency rates for the AVGs in patients with the aa genotype were significantly lower than the corresponding rates for the bb and ab genotype groupings (p =. 01, p =. 01 and p =. 04 for the three respective time points; Kaplan–Meier). ecNOS gene intron 4 VNTR polymorphism is linked with the pathogenesis of vascular access thrombosis in Turkish patients undergoing hemodialysis.  相似文献   
74.
The use of mesh has become the gold standard in hernia operations recently due to advantages such as lower recurrence rates, lower post-surgical pain and earlier return to work. Plug mesh application, first described by Robins and Rutkow [Robbins AW, Rutkow IM (1993) The mesh-plug hernioplasty. Surg Clin North Am 73:501–512], is a popular method of hernia repair. Although rare, there may be complications of surgery using plug mesh. This report presents a case of mechanic bowel obstruction due to mesh migration, 3 years after a left inguinal hernia repair with plug mesh method.  相似文献   
75.

Background

There is very limited data about the cognitive structure of bipolar depression when compared to unipolar depression. The aim of the study was to look into the differences between unipolar and bipolar depressed patients regarding their cognitive structure in view of Beck's cognitive theory.

Methods

In this study, 70 bipolar patients during a depressive episode, 189 unipolar depressed patients and 120 healthy subjects were recruited. The participants were interviewed by using a structured clinical diagnostic scale. To evaluate the cognitive structure differences, the Automatic Thoughts Questionnaire (ATQ) and the Dysfunctional Attitude Scale (DAS) were used.

Results

We found that on the mean ATQ total score, the unipolar depressed patients scored significantly higher (92.9 ± 22.7) than both the bipolar depressed patients (73.2 ± 24.7) and the healthy subjects (47.1 ± 19.6), even after controlling for all confounding factors, e.g. gender, marital status, depressive symptom severity (F = 157.872, p < 0.001). The bipolar depressed patients also scored significantly higher on the mean ATQ total score than the healthy controls. On the mean DAS total score, and on the mean score of its subscale of need for approval, the bipolar depressed patients scored (152.8 ± 21.2 and 48.2 ± 7.4, respectively) significantly higher than both the unipolar depressed patients (160.9 ± 29.0 and 51.9 ± 9.7, respectively) and the healthy subjects (127.9 ± 32.8 and 40.2 ± 12.2, respectively), even after controlling for any confounding factor (F = 45.803 [p < 0.001] and F = 43.206 [p < 0.001], respectively). On the mean score of the perfectionistic attitude subscale of the DAS, the depressed groups scored significantly higher than the healthy subjects, but they did not seem to separate from each other (F = 41.599, p < 0.001).

Conclusions

These results may help enhance the understanding of the potentially unique psychotherapeutic targets and the underlying cognitive theory of bipolar depression.  相似文献   
76.
The aim of this study was to develop a novel nanosize drug candidate for cancer therapy. For this purpose, (S)-methyl 2-[(7-hydroxy-2-oxo-4-phenyl-2H-chromen-8-yl)methyleneamino]-3-(1H-indol-3-yl)propanoate (ND3) was synthesized by the condensation reaction of 8-formyl-7-hydroxy-4-phenylcoumarin with l -tryptophan methyl ester. Its controlled release formulation was prepared and characterized by different spectroscopic and imaging methods. The cytotoxic effects of ND3 and its controlled release formulation were evaluated against MCF-7 and A549 cancer cell lines, and it was found that both of them have a toxic effect on cancer cells. For drug design and process development, the molecular docking analysis technique helps to clarify the effects of some DNA-targeted anticancer drugs to determine the interaction mechanisms of these drugs on DNA in a shorter time and at a lower cost. By using the molecular docking analysis and DNA binding assays, the interaction between the synthesized compound and DNA was elucidated and non-binding interactions were also determined. To predict the pharmacokinetics, and thereby accelerate drug discovery, the absorption, distribution, metabolism, excretion and toxicity values of the synthesized compound were determined by in silico methods.  相似文献   
77.
A 38-year-old male presented to the emergency department with abdominal pain and bulge. He had a history of irritable bowel syndrome for 1 year with complaint of dyspepsia. Physical examination revealed a distended abdomen with a huge palpable mass located in the paraumblical region. Laboratory findings revealed a high white blood cell count with neutrophil predominance. Contrast-enhanced computed tomography (CT) showed a 23-cm, oval-shaped, grossly necrotic, low-attenuation mass with peripherally located dominant vessels. Magnetic resonance imaging (MRI) with diffusion weighted imaging (DWI) suggested a highly malignant tumor with prominent diffusion restriction especially at the periphery of the mass. On surgery, macroscopic examination showed a macrolobulated, hypervascular, reddish brown mass attached to the parietal peritoneum with a stalk. Ewing’s sarcoma (ES) was diagnosed on histopathological examination with small round cells.  相似文献   
78.
79.
PURPOSE: To investigate the contribution of HCV infection to insulin resistance in chronic haemodialysis patients. MATERIALS AND METHODS: The study was performed with 55 patients who were on regular haemodialysis therapy three times per week. Of the 55 patients, 34 (20 females and 14 males with an average age of 40.9 years) were anti-HCV (+) and were defined as the HCV (+) group. The remaining 21 patients (8 females and 11 males with an average age of 50 years) were negative for HCV and other viral markers and were defined as the HCV (-) group. BMI of all patients were below 27. Insulin resistance (IR) was calculated according to the HOMA formula and patients were called HOMA-IR (+) if their HOMA scores were higher than 2.5. All of the HOMA-IR (+) patients in both groups were called the HOMA-IR (+) subgroup. None of the patients had a history of drug use or any diseases that were related to insulin resistance except uremia. In both groups and the healthy control group, insulin and glucose levels were studied at three different venous serum samples taken at 5- minute intervals after 12 hours of fasting. Other individual variables were studied at venous serum samples taken after 12 hours of fasting. RESULTS: HOMA scores were (3)2.5 in 22 of 34 HCV (+) patients (64.7%) and 7 of 21HCV (-) patients (33.33%) (p=0.024). Insulin levels of HCV (+) group (13.32 +/- 9.44mIU/mL) were significantly higher than HCV (-) (9.07 +/- 7.39mIU/mL) and the control groups (6.40 +/- 4.94mIU/ mL) (p=0.039 and p=0.021 respectively). HCV (+) patients were younger (40.94 +/- 17.06 and 52.62 +/- 20.64 years, respectively) and had longer dialysis duration (7.18 +/- 3.61 and 2.91 +/- 2.69 years, respectively). Significant positive correlations of HOMA score with insulin (r=0.934, p=0.000) and fasting glucose levels (r=0.379, p=0.043) were found in the HOMA- IR (+) subgroup. Also, a significant positive correlation was found between ALT and insulin levels in the HOMA IR (+) subgroup. C-peptide levels of both HCV (+) and (-) groups were significantly higher than the control group (p < 0.001). There were not any significant correlations between HOMA score and some of the other individual variables including levels of triglyceride, ferritin, ALT, iPTH and Mg in any of the groups. CONCLUSION: In chronic haemodialysis patients; HCV infection is related to a high prevalence of insulin resistance, higher insulin and glucose levels.  相似文献   
80.
BACKGROUND: The purpose of this study was to examine the effects of exercise on maximum QTc interval (QTcmax) and QTc dispersion (QTcd) in diabetic patients without clinically evident heart disease. METHODS: Seventy-six diabetic patients who had no coronary artery disease or hypertension (group I; mean age 48 +/- 9 years old) and 40 healthy volunteers (group II; mean age 46 +/- 13 years old) were enrolled in the study. Cases with clinically evident heart disease were excluded from the study. Resting 12-lead electrocardiogram (ECG) and maximal treadmill exercise test (according to Bruce protocol) were performed in all cases. The QTcmax interval was determined at rest (RQTcmax) and during peak exercise (PQTcmax). Also, the QTcd was measured at rest (RQTcd) and during peak exercise (PQTcd). Autonomic neuropathy was assessed by measuring the heart rate variability (HRV). RESULTS: There was no significant difference between clinical characteristics of two groups. In group I, HRV parameters were significantly lower than group II. RQTcd, PQTcd, RQTcmax, and PQTcmax were significantly longer in group I (56 +/- 16 vs 34 +/- 11; P< 0.001, 62 +/- 22 vs 40 +/- 15; P < 0.001, respectively). In diabetic patients, there was no significant difference between RQTcmax and PQTcmax (428 +/- 19 vs 420 +/- 31; P > 0.05), and no significant difference was present between RQTcd and PQTcd (56 +/- 16 vs 62 +/- 22; P > 0.05, respectively). CONCLUSION: Exercise does not affect QTcd in patients with diabetes mellitus and without clinically evident heart disease.  相似文献   
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