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61.
Ahn HS  Park CM  Lee SW 《BJU international》2002,89(6):526-530
OBJECTIVES: To assess the changes in sex hormone levels with age and the relationship of sexual functioning to testosterone levels, evaluating serum testosterone levels and erectile function in men with lower urinary tract symptoms (LUTS). PATIENTS AND METHODS: The study included 213 men with LUTS (age range 31-78 years) who had no confirmed erectile dysfunction. Their serum total and free testosterone, and sex-hormone binding globulin (SHBG) levels were measured, and they completed the International Index of Erectile Function (IIEF) questionnaire. RESULTS: The total and free testosterone levels decreased and SHBG increased with age, but only the change in free testosterone and SHBG were statistically significant. The correlation with age was closer for free testosterone (r = - 0.356, P < 0.001) than for SHBG (r = 0.177, P = 0.010). Regression analysis of the five domain scores of the IIEF and three hormonal levels, after correcting for age, showed that free testosterone level was significantly correlated with erectile function (r = 0.2136, P = 0.005) and orgasmic function (r = 0.179, P = 0.020), but SHBG levels were significantly correlated only with orgasmic function (r = - 0.154, P = 0.046). Total testosterone levels showed no significant correlation with any of the five domains of the IIEF. CONCLUSIONS: Of the sex hormone levels, the change in free testosterone correlated most closely with ageing and had the closest correlation with sexual activity. Contrary to previous reports, free testosterone and SHBG levels were significantly correlated with orgasmic function and/or erectile function rather than sexual desire. A complete study of sex hormone levels is needed to evaluate patients with erectile dysfunction.  相似文献   
62.
Background: The authors determined whether desflurane altered myocardial excitation-contraction coupling and electrophysiologic behavior in the same manner as isoflurane and sevoflurane.

Methods: The effects of desflurane on isometric force in guinea pig ventricular papillary muscles were studied in modified standard and in 26 mm K+ Tyrode solution with 0.1 [mu]m isoproterenol. Desflurane effects on sarcoplasmic reticulum Ca2+ release were also determined by examining its actions on rat papillary muscles, guinea pig papillary muscles in low-Na+ Tyrode solution, and rapid cooling contractures. Normal and slow action potentials were recorded using a conventional microelectrode technique. Ca2+ and K+ currents of guinea pig ventricular myocytes were examined.

Results: Desflurane (5.3% and 11.6%) decreased peak force to approximately 70% and 40% of the baseline, respectively, similar to the effects of equianesthetic isoflurane concentrations. With isoproterenol in 26 mm K+ Tyrode solution, desflurane markedly depressed late peaking force and modestly depressed early peak force. The rested state contractions of rat myocardium or guinea pig myocardium in low-Na+ Tyrode solution were modestly depressed, whereas rapid cooling contractures were virtually abolished after desflurane administration. Desflurane significantly prolonged the action potential duration. Desflurane reduced L-type Ca2+ current and the delayed outward K+ current but did not alter the inward rectifier K+ current.  相似文献   

63.
A biomechanical study comparing simulated lytic vertebral metastases treated with laser-induced thermotherapy (LITT) and vertebroplasty versus vertebroplasty alone. To investigate the effect of tumor ablation using LITT prior to vertebroplasty on biomechanical stability and cement fill patterns in a standardized model of spinal metastatic disease. Vertebroplasty in the metastatic spine is aimed at reducing pain, but is associated with risk of cement extravasation in up to 10%. Six pairs of fresh-frozen cadaveric thoracolumbar spinal motion segments were tested in axial compression intact, with simulated metastases and following percutaneous vertebroplasty with or without LITT. Canal narrowing under load, pattern of cement fill, load to failure, and LITT temperature and pressure generation were collected. In all LITT specimens, cement filled the defect without extravasation. The canal extravasation rate was 33% in specimens treated without LITT. LITT and vertebroplasty yielded a trend toward improved posterior wall stability (P = 0.095) as compared to vertebroplasty alone. Moderate rises in temperature and minimal pressure generation was seen during LITT. In this model, elimination of tumor by LITT, facilitates cement fill, enhances biomechanical stability and reduces the risk of cement extravasation.  相似文献   
64.
65.
Ruptured aneurysms of the distal anterior choroidal artery (AchA) are extremely rare and management is dictated by clinical presentation. This report describes a rare patient with a distal AchA aneurysm and subarachnoid and intraventricular haemorrhage. A 60-year-old woman presented with a sudden onset of severe headache and vomiting. No aneurysms could be found on initial angiograms. A repeat angiogram performed 10 days after admission demonstrated an aneurysm in a branch of the cisternal segment of the left AchA without a definite neck. Surrounding vessels showed multifocal stricture and dilatation. Microsurgical clipping was not performed because the patient died suddenly due to pulmonary failure. The aetiology of the aneurysm in this case and surgical strategy are discussed.  相似文献   
66.
Christopoulos A  Ahn SM  Klein JD  Kim S 《Head & neck》2011,33(8):1220-1229
Angiogenesis is a necessary process for tumor progression and is driven through molecular interactions between cancer cells and neighboring vascular endothelial cells. The primary mediators of angiogenesis are the vascular endothelial growth factors and their respective receptors on endothelial cells. There are several U.S. Food and Drug Administration-approved anti-angiogenic agents in clinical use. In head and neck cancer there are clinical trials assessing the efficacy of anti-angiogenic agents in combination with chemoradiation therapy. Although the aforementioned growth factors and receptors have been traditionally viewed as anti-angiogenic targets, there are concomitant efforts to understand the role these molecules play within the tumor cells. In this review, we first discuss the biology of angiogenic proteins and the targeting of angiogenic molecules for cancer treatment. We summarize the current clinical trials of anti-angiogenic therapies in head and neck squamous cell carcinoma. Finally, the additional role these molecules play in tumor progression independent of angiogenesis is discussed.  相似文献   
67.
Jeong IG  Ro JY  Kim SC  You D  Song C  Hong JH  Ahn H  Kim CS 《BJU international》2011,108(1):38-43
Study Type – Therapy (case series)
Level of Evidence 4 What’s known on the subject? and What does the study add? Although extranodal extension in node‐positive patients may provide prognostic information in certain urological malignancies, contradictory results have been reported in node‐positive patients after radical cystectomy for bladder cancer. We examined whether extranodal extension could have an impact on the outcomes of node‐positive patients who underwent radical cystectomy for bladder cancer in a single large tertiary hospital. We have shown that the presence of extranodal extension was not an independent prognostic factor in node‐positive patients after radical cystectomy and pelvic lymphadenectomy for bladder cancer.

OBJECTIVE

? To examine whether extranodal extension (ENE) has an impact on the outcome of node‐positive patients who underwent radical cystectomy for bladder cancer.

PATIENTS AND METHODS

? Of 543 consecutive patients who underwent radical cystectomy for urothelial carcinoma of the bladder between 1990 and 2007, 112 patients with lymph node metastasis detected on histological examination were evaluated with regard to recurrence‐free survival (RFS) and disease‐specific survival (DSS) based on ENE status.

RESULTS

? The overall 5‐year RFS and DSS rates were 22.3% and 33.8%, respectively. ENE was observed in 41 (36.6%) of the 112 patients. ? The presence of ENE was associated with advanced pathological nodal status (P= 0.004), more positive lymph nodes (P= 0.006), and higher lymph node density (P < 0.001). ? The incidence of positive ENE increased with large positive lymph node diameter (P < 0.001). ? Multivariate analysis showed that lymph node density (hazard ratio (HR) = 2.39, 95% CI 1.09–5.24, P= 0.029; and HR = 3.13, 1.43–6.84, P= 0.004) and use of adjuvant chemotherapy (HR = 1.80, 1.02–3.20, P= 0.041; and HR = 2.07, 1.13–3.79, P= 0.018) were significant predictors of RFS and DSS, respectively. ? After adjustment for other prognostic factors, ENE was not significantly related to RFS (P= 0.825) and DSS (P= 0.961) by multivariate analysis.

CONCLUSIONS

? The presence of ENE was not an independent prognostic factor in node‐positive patients after radical cystectomy for bladder cancer. ? Additional prospective studies are needed to determine the independent prognostic role of ENE.  相似文献   
68.
Koo KH  Ahn IO  Kim R  Song HR  Jeong ST  Na JB  Kim YS  Cho SH 《Radiology》1999,211(3):715-722
PURPOSE: To determine the accuracy of magnetic resonance (MR) cholangiography for demonstration of the biliary tract and detection of biliary complications in patients who have undergone orthotopic liver transplantation. MATERIALS AND METHODS: Breath-hold half-Fourier rapid acquisition with relaxation enhancement MR cholangiography was performed in 25 patients who had undergone orthotopic liver transplantation. MR cholangiograms were prospectively and independently interpreted by two radiologists for depiction of the biliary tract and ductal anastomosis and for complications (eg, biliary dilatation, stricture, stones). MR cholangiographic findings were correlated with findings from direct cholangiography (n = 24) and surgery (n = 1). RESULTS: MR cholangiography completely demonstrated first-order intrahepatic bile ducts in 23 (92%) patients, the donor extrahepatic bile duct in 25 (100%), the recipient extrahepatic bile duct in 17 of 18 (94%), and the anastomosis in 24 (96%). The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of MR cholangiography for detection of biliary dilatation and stricture were each 100%. Complete interobserver agreement occurred in the detection of biliary dilatation and stricture. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of MR cholangiography for detection of stones were 100% for one radiologist and 86%, 100%, 96%, 100%, and 95%, respectively, for the other. Both radiologists agreed on the diagnosis of bile duct stones in six of seven cases (kappa = 0.90). CONCLUSION: MR cholangiography enables accurate depiction of the biliary tract and detection of biliary complications in patients with an orthotopic liver transplant.  相似文献   
69.
Carotid interposition grafts (CIP) for carotid artery revascularization can be a viable alternative to carotid endarterectomy (CEA) or carotid artery stenting (CAS) for complex carotid disease. This is a retrospective review of the UCLA 17-year experience with CIP for carotid reconstruction. Carotid operations performed between 1988 and 2005 revealed 41 CIP procedures in 39 patients using polytetrafluoroethylene (PTFE, n = 31) or reversed greater saphenous vein (Vein) (n = 10). Perioperative data and long-term follow-up for each conduit were statistically compared. There were no significant differences in demographics, risk factors, operative indications, complications, or 30-day perioperative deaths. There was one postoperative stroke in each group, for an overall stroke rate of 4.9% (PTFE 3.2%, Vein 10%). There was one asymptomatic occlusion and there were two high-grade restenoses in the PTFE group compared with one asymptomatic occlusion and one high-grade restenosis in the Vein group. Overall primary patency was 90% and the assisted primary patency was 97% for the PTFE group (mean follow-up 50 months), whereas primary patency was 80% (mean follow-up 30 months) in the Vein group. CIP is a safe and effective technique with excellent long-term follow-up for complex carotid reconstruction when CEA or CAS may be contraindicated.  相似文献   
70.
J Y Ahn  S O Kwon  J Y Joo 《Neurologia medico-chirurgica》2001,41(12):603-5; discussion 606
A 50-year-old male presented with an extremely rare dorsal wall aneurysm of the internal carotid artery manifesting as intracerebral hemorrhage. Computed tomography demonstrated intracerebral hemorrhage on the frontal base. Magnetic resonance imaging clearly showed the hemorrhage was related to an aneurysm of the internal carotid artery. Cerebral angiography disclosed an elongated aneurysm of the dorsal wall of the internal carotid artery. The aneurysm was packed as fully as possible with Guglielmi detachable coils to achieve complete obliteration. The patient was discharged without neurological deficits. Dorsal internal carotid artery aneurysms have a high risk of premature rupture due to their unusual shape and position, adhesion to the brain tissue, and fragile neck. Direct clipping requires careful brain retraction, necessary exposure of the aneurysm, and gentle neck manipulation. Endovascular treatment is an alternative method for obliteration of the aneurysmal sac.  相似文献   
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