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91.
Neuronal tumors of the central nervous system: radiologic findings and pathologic correlation. 总被引:17,自引:0,他引:17
Ji Hoon Shin Ho Kyu Lee Shin Kwang Khang Dong Won Kim Ae Kyung Jeong Kook Jin Ahn Choong Gon Choi Dae Chul Suh 《Radiographics》2002,22(5):1177-1189
Pure neuronal and mixed neuronal-glial tumors of the central nervous system are uncommon but fascinating because they are less aggressive than the more common glial tumors and their prognosis is excellent. Neurologic manifestations are varied and include seizures, symptoms of increased intracranial pressure, and neurologic deficits according to tumor location. Many neuronal tumors of the central nervous system demonstrate characteristic radiologic findings. At magnetic resonance (MR) imaging, gangliocytomas demonstrate low signal intensity on T1-weighted images, high signal intensity on T2-weighted images, and frequent enhancement on gadolinium-enhanced T1-weighted images. Characteristic MR imaging findings of Lhermitte-Duclos disease are a nonenhancing mass in a cerebellar hemisphere with a striated pattern. Central neurocytomas are typically located in the lateral ventricles near the foramen of Monro with a characteristic attachment to the septum pellucidum. Ganglioneurocytoma is a rare variant of central neurocytoma that is characterized by differentiation toward ganglion cells. In ganglioglioma, a well-defined cystic mass with a solid mural nodule is typically seen. Extension of enhancement to the leptomeninges is characteristic of desmoplastic infantile ganglioglioma and correlates with the firm dural attachment of the solid component. Dysembryoplastic neuroepithelial tumor has a well-demarcated, multilobulated or gyriform appearance. 相似文献
92.
Reduction of flow-related signal loss in flow-compensated 3D TOF MR angiography, using variable echo time (3D TOF-VTE). 总被引:1,自引:0,他引:1
Eun-Kee Jeong Dennis L Parker Jay S Tsuruda Jong-Yun Won 《Magnetic resonance in medicine》2002,48(4):667-676
High-resolution MRA with phase/frequency flow compensation may require very long echo times (TEs). Variable TE (VTE) was implemented into flow-compensated 3D TOF to minimize the effective TE and reduce the flow-related signal void. The k-space of the 3D TOF was divided into segment groups ranging from two to 32 segments with different TEs. The TEs were minimized and the flow-compensation gradient lobes were calculated to null the total first moment at the peak of the echo for each segment. Possible artifacts and off-resonance effects were evaluated, with respect to the number of TE segments, using the point spread function (PSF) and corresponding experiments. The optimal number of TE segments for the least artifact was determined to be one-half of the number of slices. Two types of artifacts caused by VTE were predicted and subsequently observed. The developed pulse sequence 3D TOF-VTE was tested on clinical MRI systems, by performing scans of the cervical carotid artery and intracranial carotid artery at the carotid siphon. The signal distribution near the bifurcation and the siphon was much more uniform with VTE, and the flow-related signal loss was greatly reduced. The resultant MR angiograms provided improved vessel detail. The results show that VTE improved the quality of flow-compensated 3D TOF MRA. 相似文献
93.
PURPOSE: Increasing clinical importance is being placed on the role of differential renal function (DRF) in the management of congenital ureteropelvic junction obstruction. Supranormal DRF of the hydronephrotic kidney on renal scan is a puzzling phenomenon and is hypothesized to be due to an increase in single nephron filtration or nephron volume without sound evidence. We studied the histopathological changes of hydronephrotic kidneys to determine whether glomerular hypertrophy underlies supranormal DRF. MATERIALS AND METHODS: We retrospectively evaluated the records of 3 females and 32 males with unilateral congenital hydronephrosis who underwent pyeloplasty. Mean patient age at operation was 12.6 months (range 0.1 to 144). Needle biopsies from 3 different sites at the lower pole of the kidney were performed during surgery. To evaluate the presence of glomerular hypertrophy, the maximal planar area of glomeruli was measured under light microscopy using an image analyzer. Tissue samples obtained from kidneys without a history of urinary tract disease at autopsy were used as controls. The mean glomerular areas of the patient and control groups were evaluated according to DRF and age. RESULTS: The mean glomerular area values of the patient group were smaller than those of the control group, except for 4 patients. The glomerular areas of the hydronephrotic kidneys with supranormal DRF were not significantly different from those of the control group. Instead, the probability of larger renal glomeruli increased with decreasing DRF (p = 0.1155). CONCLUSIONS: Increased nephron volume can be discounted as a cause of supranormal DRF. 相似文献
94.
Sung Rak Lee Hyoung Won Jang Dhong Won Lee Sang Wook Nam Jeong Ku Ha Jin Goo Kim 《Clinics in Orthopedic Surgery》2013,5(3):188-194
Background
The purpose of this study is to report a modified transtibial technique to approach the center of anatomical femoral footprint in anterior cruciate ligament (ACL) reconstruction and to investigate the accurate femoral tunnel position with 3-dimensional computed tomography (3D-CT) and radiography after reconstruction.Methods
From December 2010 to October 2011, we evaluated 98 patients who underwent primary ACL reconstruction using a modified transtibial technique to approach the center of anatomical femoral footprint in single bundle ACL reconstruction with hamstring autograft. Their femoral tunnel positions were investigated with 3D-CT and radiography postoperatively. Femoral tunnel angle was measured on the postoperative anteroposterior (AP) radiograph and the center of the femoral tunnel aperture on the lateral femoral condyle was assessed with 3D-CT according to the quadrant method by two orthopedic surgeons.Results
According to the quadrant method with 3D-CT, the femoral tunnel was measured at a mean of 32.94% ± 5.16% from the proximal condylar surface (parallel to the Blumensaat line) and 41.89% ± 5.58% from the notch roof (perpendicular to the Blumensaat line) with good interobserver (intraclass correlation coefficients [ICC], 0.766 and 0.793, respectively) and intraobserver reliability (ICC, 0.875 and 0.893, respectively). According to the radiographic measurement on the AP view, the femoral tunnel angles averaged 50.43° ± 7.04° (ICC, 0.783 and 0.911, respectively).Conclusions
Our modified transtibial technique is anticipated to provide more anatomical placement of the femoral tunnel during ACL reconstruction than the former traditional transtibial techniques. 相似文献95.
We investigated the therapeutic effect of topical Risedronate (RIS) on a mouse model of estrogen-deficient osteoporosis. Fourteen-week-old female mice were ovariectomized and assigned to 4 groups: SHAM-operated (SHAM), OVX mice treated with vehicle (OVX-V), OVX mice treated with 0.2% RIS (OVX-0.2% RIS), and OVX-mice treated with 0.02% RIS (OVX-0.02% RIS). Topical samples containing RIS were prepared in 10% (w/w) polyethylene glycol (PEG, MW 400) and 80 μg of sample was spread on the mice's mid-backs every 3 days for 5 weeks. Micro-CT analysis of femora demonstrated that OVX-0.2% RIS exhibited a 29% greater bone mineral density and 24% greater bone volume fraction than that of OVX-V group. Investigation of the trabecular bone in OVX-0.2% RIS revealed a 24% higher bone volume (BV/TV), 51% higher trabecular number (Tb.N), and 40% lower trabecular separation (Tb.Sp) compared to OVX-V mice. Additionally, bone phenotypes of tibiae were further confirmed by histological analysis. OVX-0.2% RIS group exhibited a 494% greater BV/TV, 464% less Tb.Sp, 81% greater active osteoclast surface (Oc.S/BS) and 26% less osteoclast number (N.Oc/BS) than that of OVX-V group. Collectively, these results indicated that topical delivery of RIS has powerful pharmaceutical effects on the prevention of osteoporosis and bone turnover. 相似文献
96.
Background
Knowledge of the intraoperative location of lesions is a prerequisite for deciding the proper extent of gastric resection or the choice of anastomosis technique during totally laparoscopic distal gastrectomy (TLDG) for early gastric cancer (EGC). In this study we introduce a novel tumor localization method for TLDG: endoscopic blood tattooing.Methods
Twenty-three consecutive patients scheduled for TLDG for EGC were enrolled in this prospective study. The day before surgery, 2–3?ml of autologous blood was injected into the gastric muscle layer at 3–4?cm proximal to the lesion during endoscopy.Results
The study subjects consisted of 15 males and 8 females with a mean age of 61?±?10.4?years. During surgery, the endoscopic blood tattooed sites were successfully identified in all 23 patients. No complications associated with the procedure occurred, and no patient had microscopic residual tumor cells at the proximal resection margin, with a mean proximal margin length of 3.3?±?2.7?cm. Eighteen patients underwent TLDG with Billroth II anastomosis, four patients with Roux-en-Y gastrojejunostomy, and one patient with laparoscopic total gastrectomy. At final pathologic examinations, 20 patients were of stage IA and 3 were of stage IB according to the UICC TNM classification (6th ed.).Conclusions
Endoscopic blood tattooing provides a simple and useful means of localizing lesions during TLDG for EGC. Although the superiority of this technique over other localization methods needs to be evaluated further, the authors recommend endoscopic blood tattooing as an alternative to other intraoperative localization methods for laparoscopic surgery for EGC. 相似文献97.
Lee JY Park SY Jeong TY Moon HS Kim YT Yoo TK Choi HY Park HY Lee SW 《Journal of andrology》2012,33(3):397-403
This prospective study evaluated the safety of tadalafil 5 mg taken once a day in terms of hypotensive side effects and whether it improves lower urinary tract symptoms (LUTS) and restores sexual function in patients with erectile dysfunction who are receiving concomitant α-blocker (AB) therapy for benign prostatic hyperplasia (BPH). A total of 158 LUTS/BPH patients receiving AB therapy for ≥3 months were given tadalafil 5 mg once a day. Before treatment with tadalafil (V1), and 4 weeks (V2) and 12 weeks (V3) after starting tadalafil, blood pressure, heart rate, International Prostate Symptom Score (IPSS), maximal urine flow rate (Qmax), postvoiding residual urine volume, and International Index of Erectile Function (IIEF-5) score were measured. Of the 158 LUTS/BPH patients, a total of 119 completed the trial. Blood pressure (systolic and diastolic) and heart rate did not change. IPSS and IIEF-5 scores improved significantly, but Qmax and postvoiding residual urine volume did not; however, in the 39 men with a low baseline Qmax (≤10 mL/s), Qmax rose significantly from 7.97 ± 1.44 mL/s (baseline) to 8.91 ± 1.60 mL/s (V3; P = .012). The remaining patients (baseline Qmax >10 mL/s) did not change. At V2 and V3, adverse side effects were observed in 10 men (7.30%) and 6 men (5.04%), respectively. Facial flushing was the most common adverse side effect (6 men at V2 and 4 men at V3), followed by headache (2 men each at V2 and V3) and dizziness (2 men at V2). Two patients dropped out of the study because of adverse side effects. In conclusion, tadalafil 5 mg once a day in combination with AB appeared to have few adverse effects on hypotensive events and can improve LUTS and restore sexual function. 相似文献
98.
Although cisplatin is a highly effective antineoplastic agent, nephrotoxicity is its major clinical problem. Recently, it was reported that Spirulina, a blue-green algae, has potent antioxidant properties. The aim of this study was to establish the possible protective role of C-phycocyanin (PC), one of the active ingredients of Spirulina, against cisplatin-induced nephrotoxicity. This study was carried out using human kidney-2 (HK-2) cells and male C57BL6 mice. Cells and mice were divided into four groups; untreated control group, PC-treated control group, cisplatin-treated group, and PC plus cisplatin-treated group. The molecular, functional, and structural parameters were measured. PC significantly attenuated blood urea nitrogen, serum creatinine, renal histological damages, and apoptotic cell death in cisplatin-treated mice. The cisplatin-induced cell death was significantly attenuated in cells pretreated with PC. PC also significantly attenuated the elevation of p-ERK, p-JNK, and p-p38 induced by cisplatin treatment. The expression of Bax, caspase-9, and caspase-3 in cisplatin-treated cells were also decreased by PC treatment. In conclusion, PC ameliorates cisplatin-induced nephrotoxicity and, at least in part, suppression of p-ERK, p-JNK, p-p38, Bax, caspase-9, and caspase-3 may be involved in this mechanism. 相似文献
99.
In Gab Jeong Dalsan You Jongwon Kim Seong Cheol Kim Jun Hyuk Hong Hanjong Ahn Choung-Soo Kim 《World journal of urology》2012,30(6):815-820
Introduction
Preoperative factors favoring the performance of non-orthotopic bladder substitution (OBS) after radical cystectomy for muscle-invasive bladder cancer were identified.Patients and methods
We retrospectively reviewed the medical records of 730 patients who underwent radical cystectomy for urothelial carcinoma of the bladder. After excluding 75 patients who were unable to undergo OBS due to the tumor location or elevated serum creatinine level, we assessed the preoperative factors in the remaining 655 patients. Multivariate logistic regression analysis was performed to identify the independent preoperative predictors of type of urinary diversion.Results
Of the 655 patients, 171 (26.1%) underwent non-OBS. Patients who underwent non-OBS were more likely to be older and females, to have a lower educational status, non-organ confined disease, more comorbid medical conditions, more impaired performance status, lower body mass index, anemia, azotemia, and hypoalbuminemia, and to be treated by less-experienced surgeons (P?<?0.05 each). After adjusting for provider-based factors, multivariate analysis showed that factors independently associated with non-OBS included advanced age (odds ratio [OR] 4.10, P?<?0.001), female gender (OR 2.08, P?=?0.027), ECOG performance status (??1 vs 0, OR 5.20, P?<?0.001), low educational status (OR 1.59, P?=?0.042), clinically node-positive disease (OR 2.36, P?=?0.003), anemia (OR 1.67, P?=?0.041), azotemia (OR 3.97, P?<?0.001), and hypoalbuminemia (OR 1.84, P?=?0.046).Conclusion
Several patient-based as well as provider-based factors were associated with the type of urinary diversion after radical cystectomy. Advanced age, female gender, low performance status, low education level, clinically node-positive disease, anemia, hypoalbuminemia, and azotemia were associated with non-OBS, as surgery was performed by relatively inexperienced surgeons. 相似文献100.
Pil Whan Yoon Young Ho Shin Jeong Joon Yoo Kang Sup Yoon Hee Joong Kim 《Clinics in Orthopedic Surgery》2012,4(1):66-71