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81.
BACKGROUND: The primary goal of ultrasonography (US) in the evaluation of a thyroid nodule is to determine its malignancy, although the diagnosis of a malignant nodule on the basis of US alone is nearly impossible. The aim of this prospective study was to evaluate the predictive value of sonographic features in the preoperative diagnosis of malignant thyroid nodules, and to determine the important features of sonography. METHODS: This prospective study included 550 consecutive patients with , thyroid nodules. Nodules were divided into two groups on the basis of pathological diagnosis: group 1 consisted of 1,633 nodules with a benign pathology, and group 2 consisted of 293 nodules with a malignant pathology. RESULTS: Microcalcifications, blurred nodular margins, and solid and hypoechoic appearance were more common in malignant nodules compared to benign nodules (89.1% versus 5%; 64.5% versus 4.7%; 81.6% versus 30.6% ; and 62.5% versus 43.1%, respectively; p < 0.001). There was a positive correlation between the detection of malignant thyroid nodules and microcalcification (rs = 0.791, p = 0.0001), blurred nodular margin (rs = 0.625, p = 0.0001), solid appearance (rs = 0.376, p = 0.0001), and hypoechoic appearance (rs = 0.141, p = 0.0001). Microcalcifications, blurred nodular margins, and solid and hypoechoic appearance were independent determinants of malignancy upon US examination of thyroid nodules (OR: 159, OR: 37, OR: 9.9, and OR: 2.2, respectively). CONCLUSION: Although we did not identify a single feature indicative of malignancy in the sonographic examination of nodules, microcalcification and blurred margin were the strongest correlates for malignancy.  相似文献   
82.
Aim  In recent years significant progress has been made in identifying and quantitating physico-chemical processes involved in urinary stone formation. The ability of urine to inhibit calcium oxalate crystallization is an important mechanism against stone formation. Dietary factors appear to affect the ability of urine to inhibit calcium oxalate crystallization. These factors encouraged us to study the effects of lemon and orange juices on calcium oxalate crystallization in vitro. Material and methods  The nucleation and aggregation of calcium oxalate monohydrate crystals were studied using turbidimetric 30-min time course measurements of optic density at 620 nm after mixing solutions containing calcium chloride and sodium oxalate at 37°C, pH 5.7. The formation of crystals is induced by the addition of the oxalate and calcium solution. The effects on calcium oxalate crystal growth of trisodium citrate, lemon and orange juices were examined. The effects of lemon and orange juices were evaluated by the addition of 50 ml of juices. The optical density is measured at physiological conditions. The maximum increase of optic density with time, termed SN, reflects maximum rate of formation of new particles. After an equilibrium has been reached, a progressive decrease of optic density with time is observed. Rate of aggregation, SA, is derived from the maximum decrease in optic density. Results  Among the modifiers studied, citrate decreased both SN and SA (P < 0.001). Lemon juice was also found to inhibit the rate of crystal nucleation and aggregation. But orange juice did not have any effect on the calcium oxalate crystallization (P > 0.05). Conclusion  These results show that effective prevention of urinary stone formation should aim at restoring the urine’s ability to inhibit calcium oxalate crystallization and more emphasis should be given to dietary measures.  相似文献   
83.
The lateral recess is one of the main compression sites in lumbar spinal canal stenosis. Lumbar nerve root is mainly entrapped by bony tissue in compression syndrome. The patient has a long history of back pain in conjunction with claudication symptoms. Besides laminotomy and facetectomy techniques, several specific surgical approaches to treat the lateral recess stenosis have been described. The surgical technique of bilateral lateral recess decompression via subarticular fenestrations used in this study is a less invasive technique, which enables to decompress the neural structures while preserving as much of the bony structures and ligamentum flavum as preferred. In 16 patients, we measured lateral recess heights with computerized tomography. The number of involved lumbar segments was one in 11 patients and two in 5 patients. The visual analogue scale (VAS) results were maintained before, 3 and 12 months after the operation. All patients benefited from the operations. Mean VAS scores were 7.0, 5.5, and 4.0, respectively. There were not any surgery-related complications. Mean follow-up period is 22.6 months. The surgical technique described and used in this study provides easy access to every zone of lateral recess and is safe and effective in treating the lumbar lateral recess stenosis syndrome.  相似文献   
84.
85.
Purpose To assess the outcome and prognostic factors of liver surgery for breast cancer metastasis. Methods We retrospectively examined 16 patients who underwent partial liver resection for breast cancer liver metastasis (BCLM). All patients had been treated with chemotherapy or hormonotherapy, or both, before referral for surgery. We confirmed by preoperative radiological examinations that metastasis was confined to the liver. The survival curve was estimated using the Kaplan-Meier method. Univariate and multivariate analysis were conducted to evaluate the role of the known factors of breast cancer survival. Results The median age of the patients was 54 years (range 38–68) and the median disease-free interval between the diagnoses of breast cancer and liver metastasis was 54 months (range 7–120). Nine major and 7 minor hepatectomies were performed. There was no postoperative death. The overall 1-, 3-, and 5-year survival rates were 94%, 61%, and 33%, respectively. The median survival rate was 42 months. Univariate analysis revealed that hormone receptor status, number of metastases, a major hepatectomy, and a younger age were associated with a poorer prognosis. The survival rate was not influenced by the disease-free interval, grade or stage of breast cancer, or intraoperative blood transfusions. The number of liver metastases was identified as a significant independent factor of survival according to the Cox proportional hazard model (P = 0.04). Conclusions Liver resection, when done in combination with adjuvant therapy, can improve the prognosis of selected patients with BCLM.  相似文献   
86.
Objective To investigate whether stone dimension is a restrictive factor for ureterorenoscopic procedures. Materials and methods A group of 416 patients who had undergone ureterorenoscopic pneumatic lithotripsy (URS-PL) for lower ureteral stones between January 1999 and June 2006 in our clinic had been evaluated retrospectively. Two hundred and seventy (270, 64.9%) patients were men and 146 (35.1%) were women. The mean age of the patients was 36.61 (±12.43) years. Patients were grouped according to stone dimension; 193 patients with stones smaller than 1 cm being group 1 and 223 patients with stones ≥1 cm in dimension being group 2. Stone-free rate, operative time and rate of complications of the groups were compared. Pearson’s correlation test, χ2 test, Fischer’s exact test and Student’s t-test were used for the statistical analysis. The p value was accepted as being meaningful if p < 0.05. Results For group 1, the mean operative time was 39.19 (±18.33) min. Proximal stone migration in five and false passage formation in three patients was observed. Three patients were stone-free after a second session of URS-PL. The cumulative stone-free rate was 97.4% (188/193). For group 2, the mean operative time was 48.5 (±11.31) min. About 208 (93.27%) patients were stone-free after the first session and an additional eight patients became stone-free after the second session of URS-PL. False passage, ureteral perforation, ureteral avulsion and stricture were observed in four, six, one and one patients, respectively. No proximal stone migration was observed. The cumulative stone-free rate was 96.86% (216/223). Conclusions The effectiveness of ureterorenoscopy (URS) in the treatment of distal ureteral stones was independent of stone dimension. However, the operative time was longer and the rate of perforation was higher in stones with a diameter ≥1 cm. On the other hand, the migration rate was higher in stones <1 cm in diameter. Generally speaking, there was no meaningful effect of stone dimension on complication rates.  相似文献   
87.
Objective To evaluate the relationship between the expression of E-cadherin (E-CD) and tumor recurrence and progression in patients with high-grade stage T1 urothelial carcinoma of bladder. Methods Fifty-two patients who had primary high-grade stage T1 urothelial carcinoma were enrolled to the study. The pathologic specimens of patients were evaluated and staged as T1a and T1b according to muscularis mucosae involvement by the tumor. The immunohistochemical demonstration of E-CD was accomplished by using immunoperoxidase method and all the specimens were examined under light microscope for E-CD level. Results The mean age of the patients was 64.0 ± 7.7 (range 36–81) years. The mean follow-up period was 56.4 ± 19.4 (range 14–84) months. Among 52 patients, 27 (52%) of them were stage T1b and 25 (48%) were T1a tumors. The recurrence rates for T1a and T1b groups were 52% (n = 13) and 92.6% (n = 25), respectively (P < 0.05). The expression of E-CD was homogenous in 52% of pT1a and 14.8% of T1b tumors (P < 0.05). In T1a group with recurrence, homogeneous E-CD staining ratio was 30.7% (n = 4/13), but it was 75% (n = 9/12) in T1a patients without recurrence (P < 0.05). In T1b group with recurrence, the homogenous expression of E-CD was 12% (n = 3/25) and the expression of E-CD was heterogenous in 88% (n = 22/25) of them (P < 0.05). In T1a group, progression of the disease was detected in 28% (n = 7/25) of the patients, but disease progression was seen in 55.5% (n = 15/27) of T1b group patients (P < 0.05). In T1a group with progression, heterogeneous E-CD staining ratio was 85.7% (n = 6/7), but it was 80% (n = 12/15) in T1b patients with progression. The effects of tumor number, tumor size and carcinoma in situ presence on recurrence were evaluated within each group. It was determined that parameters such as tumor number and tumor size had no significant effect on recurrence of the groups. The mean survival rates were statistically different between the groups. On multivariate analysis only E-cadherin expression (P = 0.012, odds ratio 6.291, 95% confidence interval for odds ratio 1.303–4.72) and tumor stage (P = 0.003, odds ratio 11.58, 95% confidence interval for odds ratio 2.446–8.542) remained independently significant as predictors of recurrence. Conclusion E-CD expression was decreased in pathologic specimens of bladder tumor patients with muscularis mucosae involvement and this condition correlated well with tumor recurrence.  相似文献   
88.
Background and aims The aim of this study is to evaluate the predictive accuracy of different scoring systems on surgery for perforated peptic ulcer referred to an academic department of general surgery in a tertiary reference center. Patients and methods Seventy-five consecutive patients (Male/female ratio = 64:11; mean age, 44 years; range, 16–85) with perforated peptic ulcer disease were investigated. Disease severity scores and mortality predictions were calculated using the collected data during admission. Discrimination and calibration characteristics of each system, namely, the acute physiology and chronic health evaluation II and III, the simplified acute physiology score II, and the mortality probability models (MPM) II, were determined by using the area under receiver operating characteristics curve and the Hosmer–Lemeshow goodness-of-fit test, respectively. Results Among the 75 patients included, there were eight (10.6%) mortalities. All systems had a reliable power of discrimination and calibration. Among the systems tested, MPM II was the best performing as far as discrimination and calibration characteristics were considered. The parameters of MPM II system that were related to systemic perfusion of the patient were significantly positive in patients who died compared to those who survived. Conclusions MPM II that predicted mortality at admission is better than the other systems in predicting mortality. Results also indicate the importance of maintenance of systemic perfusion of the patient at the early phases of peptic ulcer perforation.  相似文献   
89.
Background The aim of the present study was to identify the clinicopathological factors affecting locoregional recurrence (LRR) in patients with clinical stage IIIB noninflammatory breast cancer (NIBC). Methods The records of 120 stage IIIB NIBC patients treated with neoadjuvant chemotherapy (NAC) and then modified radical mastectomy followed by radiotherapy were evaluated. In this retrospective cohort, the effects of age, menopausal status, clinical tumor size, clinical response to NAC, pathological axillary status, number of positive axillary lymph nodes, pathological response to NAC, grade, lymphovascular invasion, estrogen receptor status, progesterone receptor status, Her-2-neu status, and p53 status on LRR were evaluated by univariate and multivariate analyses. Results The clinical response rate of 120 patients was 79.2% (17.5% complete and 61.7% partial), with a complete pathological response rate of 12.5%. The median follow-up was 28 months (range: 10–74 months). The LRR rate was 13.3%. Based on the univariate analysis, the clinical tumor size, clinical response rate, pathological axillary status, four or more positive axillary lymph nodes, lymphovascular invasion, and estrogen receptor status were factors that significantly affected LRR. In the multivariate analysis, however, only the clinical response rate and the number of positive axillary lymph nodes were found to be statistically significant independent factors. Conclusions Effective local control of disease can be achieved in patients with stage IIIB NIBC using a combination of NAC, surgery, and radiotherapy. However, a worse clinical response after chemotherapy and four or more positive axillary lymph nodes affect LRR negatively in these patients.  相似文献   
90.

Objectives

To investigate carbohydrate antigen (CA 19-9, CA 15-3, and CA 125) levels in the patients who had hydronephrosis with renal stones and in whom Extracorporeal shock wave lithotripsy (ESWL) was performed.

Materials and Methods

This prospective study included 20 people with no known disease for control group and 30 patients who had hydronephrosis with renal stones and in whom ESWL was performed between January 2005 and January 2006. None of patients had urinary infection and malignancy. The blood for carbohydrate antigens was taken pre-ESWL and 30 min after ESWL in both groups. CA 19-9, CA 15-3, and CA 125 in the serum were tested with the electro-immunoassay method on the Roche® E-170 apparatus with the original Roche® kit.

Results

The CA 19-9 and CA 125 values in the patients group were found to be statistically significant when compared with the control group but the CA 15-3 was not found to be significant. However, CA 19-9, CA 15-3, and CA 125 values of post-ESWL were not statistically significant when compared with pre-ESWL group (P > 0.05).

Conclusions

The average serum values of CA 125 and CA 19-9 in patients were found to be significantly high. However, serum values of CA 19-9, CA 15-3, and CA 125 were not affected by ESWL.
  相似文献   
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