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81.
Role of percutaneous image-guided biopsy in the evaluation of renal masses   总被引:1,自引:0,他引:1  
OBJECTIVE: The objective of the present study was to evaluate the indications, accuracy, complications and impact of image-guided percutaneous biopsy of renal masses. MATERIALS AND METHODS: Between 1994 and 1999, percutaneous biopsies under ultrasonography or computerized tomography guidance were performed in 33 patients with renal mass (22 men and 11 women, mean age 57.5 years, range 21-88). We retrospectively analyzed the relationship between clinical and histopathological findings, and discuss the appropriateness of the indications for image-guided percutaneous biopsy in the diagnosis of renal masses. RESULTS: The indications used in our institution were as follows: (1) clinical and radiological findings to suggest a diagnosis other than primary renal cell carcinoma (RCC) (n = 15); (2) suspicious lesions of RCC in multiple cystic renal masses (n = 7); (3) differentiation of transitional cell carcinoma of the renal pelvis from RCC (n = 7); (4) differentiation of angiomyolipoma from RCC (n = 4). Sufficient amounts of tissues were obtained from all patients for pathological diagnosis. Among 33 patients, 21 (63.6%) were diagnosed positive for malignancy, and 15 underwent surgical intervention. The histopathological findings between percutaneous biopsy and surgically resected tissue were identical in 13 cases (86.7%). No patient developed major complications requiring surgical treatment. CONCLUSION: If performed under appropriate selection of patients, percutaneous image-guided biopsy is a safe, reliable and accurate method of managing suspicious and/or indeterminate renal mass, and may contribute to the selection of appropriate clinical management by avoiding unnecessary procedures.  相似文献   
82.
Acute subdural hematoma (ASDH) is a critical condition following the onset of traumatic brain injury, and it is essential to immediately reduce elevated intracranial pressure (ICP). Single burr hole surgery/twist drill craniostomy is commonly performed in patients with ASDH as an emergency surgical intervention, usually preceding decompressive craniotomy. A novel method using a cerebrospinal fluid (CSF) drainage catheter kit for rapid drainage of ASDH is described. Percutaneous twist drill craniostomy using a CAMINO(?) micro ventricular bolt pressure-temperature monitoring kit was performed in the emergency room in 12 patients with severe ASDH. The kit contained a closed-system CSF drainage and pressure-temperature monitoring catheter, which allowed aspiration of the hematoma and monitoring of the ICP. The tip of the catheter was inserted into the hematoma from the forehead. The mean initial ICP was 61 mmHg, with a range of 31 to 120 mmHg. The liquid hematoma was aspirated, and the ICP was temporarily controlled to the normal range. Pupil dilation recovered immediately after aspiration of the hematoma in 3 patients. No complications occurred either during or after the operation. This new method for craniostomy is easy, safe, and effective to monitor and rapidly control ICP in the emergency room. This technique also offers the possibility of evaluating the patient's prognosis and determining indications for further decompressive craniectomy by the continuation of ICP control under ICP monitoring and evaluation of the reversibility of pupillary findings in ASDH patients.  相似文献   
83.
The objective of this study was to evaluate the expression levels of multiple potential molecular markers in prostate cancer to clarify the significance of these markers as prognostic indicators in patients undergoing radical prostatectomy (RP). This study included a total of 193 patients with clinically organ-confined prostate cancer who underwent RP without any neoadjuvant therapies. Expression levels of 12 proteins, including Ki-67, p53, androgen receptor (AR), matrix metalloproteinase (MMP)-2, MMP-9, vascular endothelial growth factor, Aurora-A, Bcl-2, clusterin, heat shock protein 27 (HSP27), HSP70, and HSP90, in RP specimens obtained from these 193 patients were measured by immunohistochemical staining. Of the 12 molecules, Ki-67, p53, AR, MMP-2, MMP-9, and HSP27 expression were significantly associated with several conventional prognostic factors. Univariate analysis identified these 6 markers as significant predictors for biochemical recurrence as well, while prostate-specific antigen, Gleason score, seminal vesicle invasion (SVI), surgical margin status (SMS), lymph node metastasis, and tumor volume were also significant. Of these significant factors, Ki-67 expression, SVI, and SMS appeared to be independently related to biochemical recurrence by multivariate analysis. Furthermore, there were significant differences in biochemical recurrence-free survival according to positive numbers of these three independent risk factors. These findings suggest that consideration of expression levels of potential molecular markers in RP specimens, in addition to conventional prognostic parameters, would contribute to accurate prediction of biochemical recurrence following RP in patients with clinically localized prostate cancer, and that combined evaluation of Ki-67 expression, SVI, and SMS would be particularly useful for further refinement of the system in predicting biochemical outcome.  相似文献   
84.
INTRODUCTION: The objective of this study was to determine whether the nadir value of serum prostate-specific antigen (PSA) measured by an ultrasensitive assay could be a useful predictor of biochemical recurrence after radical prostatectomy for clinically localized prostate cancer. MATERIALS AND METHODS: This study included 127 patients who underwent radical prostatectomy for clinically localized prostate cancer without neoadjuvant hormonal therapy and were pathologically diagnosed as negative for lymph node metastasis. The serum PSA value was measured using an ultrasensitive PSA assay system (Roche Diagnostics, Mannheim, Germany), and the findings were analyzed with respect to several clinicopathological factors. In this series, biochemical recurrence was defined as PSA persistently >0.2 ng/ml. RESULTS: Based on the nadir PSA value, we divided 127 patients into three groups as follows: group A (n=99):or=0.05 ng/ml. The nadir PSA value was significantly associated with preoperative PSA value, but not other conventional clinicopathological prognostic parameters. During the observation period (median 31 months, range 6-75 months), biochemical recurrence occurred in 16 patients, that is, 1 in group A (6.3%), 4 in group B (25.0%), and 11 in group C (91.7%). Multivariate analysis using the Cox proportional hazards regression model indicated that the nadir PSA value was an independent predictor for biochemical recurrence after radical prostatectomy. CONCLUSION: These findings suggest that the nadir serum PSA value measured by an ultrasensitive assay could be a useful predictor of biochemical recurrence after radical prostatectomy for clinically localized prostate cancer, and that careful follow-up should be considered in cases demonstrating a nadir PSA value>0.01 ng/ml because of the significantly higher probability of biochemical recurrence in such cases.  相似文献   
85.
A 64-year-old man was admitted due to hypokalemia-related myopathy. He was heavy drinker. He felt the stress of alcohol withdrawal during his hospitalization. The patient suffered a cardiopulmonary arrest lasting approximately 5 minutes on the fifth hospital day. One day later, ST-segment elevation was observed in leads I, aV(L), and V(2-6). Emergent cardiac catheterization was performed for suspicion of acute myocardial infarction. Normal coronary arteries with anterior akinesis of the left ventricle were revealed during the procedure. The present case may be an atypical form of "Takotsubo cardiomyopathy" in which the left ventricular contraction is due to focal anterior wall motion abnormalities.  相似文献   
86.
87.
In recent years, augmented renal clearance (ARC), in which renal function is excessively enhanced, has been reported, and its influence on β-lactam antibiotics has been investigated. In this study, we aimed to determine the optimum population pharmacokinetic model of meropenem in patients with sepsis with ARC, and evaluated dosing regimens based on renal function. Seventeen subjects (6 with ARC and 11 without) were enrolled in this study. Predicted meropenem concentrations were evaluated for bias and precision using the Bland–Altman method. To examine the dosing regimen, Monte Carlo simulation was performed to calculate the cumulative fraction of response (CFR). In patients with ARC, the bias (average of the predicted value and measured value residuals) of models constructed by Crandon et al. (2011), Roberts et al. (2009), and Jaruratanasirikul et al. (2015) were 5.96 μg/mL, 10.91 μg/mL, and 4.41 μg/mL, respectively. Following 2 g meropenem every 8 h (180 min infusion), CFR ≥ 90%, a criterion of success for empirical therapy, was achieved, even with creatinine clearance of 130–250 mL/min. For patients with sepsis and ARC, the model of Jaruratanasirikul et al. showed the highest degree of accuracy and precision and confirmed the efficacy of the meropenem dosing regimen in this patient population.  相似文献   
88.
To detect the minute electric potential inside the QRS complex, a new frequency domain method was designed using short-time First Fourier Transforms (SFFT) and high-frequency sampling (oversampling). SFFT improved the frequency resolution by oversampling that was applied to this analysis. The electric potential data of 15,000 points received weighted, running average processing and was subtracted from the original waveform to reduce the low-frequency component. The data in a segment of 160 ms, including QRS, was processed by frequency analysis with the SFFT computation routine. The ECG of healthy individuals was analyzed by this method and its usefulness evaluated. The processing waves of the X-axis, Y-axis, and Z-axis of a representative normal subject were formed into 3 groups of peak electric potential. SFFT enabled the detection of the structure inside the QRS complex without signal averaging, and is considered capable of evaluating the process of excitement inside the QRS complex in the various heart diseases.  相似文献   
89.
The treatment of patients with aggressive subclasses of myelodysplastic syndrome (MDS) remains a challenge. In an effort to improve the survival of patients with refractory anemia with excess blasts (RAEB), RAEB in transformation (RAEB-t), or acute myelogenous leukemia transformed from MDS (MDS-AML), we conducted a small trial in which 28 such patients were treated with low-dose cytosine arabinoside (LDAraC) followed by administration of macrophage colony-stimulating factor (M-CSF). The overall rate of response to the treatment was 61%, including 39% with a complete response, which is higher than rates obtained in previous studies in which LDAraC alone was administered to patients with MDS. Median survival was 23.5 months in cases of RAEB, 16.7 months in cases of RAEB-t, and 19.7 months in cases of MDS-AML. The overall survival of the study group appeared to be prolonged in comparison with a historical control group of patients treated with LDAraC alone. It is suggested that M-CSF added to the administration of LDAraC plays an active role in the therapy. No therapy-related death occurred. Some unique actions of M-CSF were suggested in this trial. It is concluded that therapy with LDAraC + M-CSF is a useful treatment option for patients with aggressive subclasses of MDS and MDS-AML to provide better response and survival.  相似文献   
90.
The LH and FSH secretions in 21 patients with anorexia nervosa were assessed by radioimmunoassay. On a single iv injection of 100 mug LH-releasing hormone (LH-RH), 8 patients showed LH response comparable to that of normal cyclic women in the follicular phase, and 5 patients showed excessive response. Although the remaining 8 patients showed almost no LH response, infusion of 400 mug LH-RH or daily im injections of LH-RH restored gonadotrophin responsiveness to LH-RH in all patients tested. The initial rise in LH during clomiphene citrate treatment was observed in 3 out of 5 patients, but the second peak of LH was found in only one patient. The initial suppression of LH following iv injection of conjugated oestrogen (Premarin) was observed in 9 out of 10 patients but a rebound increase comparable to that in normal cyclic women in the mid-follicular phase was found in only 3 patients. These results seem to suggest that impaired hypothalamic function is the cause of gonadotrophin deficiency and the resultant anovulation in most patients with anorexia nervosa.  相似文献   
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