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81.
Bertram Yuh Walter Artibani Axel Heidenreich Simon Kimm Mani Menon Giacomo Novara Ashutosh Tewari Karim Touijer Timothy Wilson Kevin C. Zorn Scott E. Eggener 《European urology》2014
Context
The role of robot-assisted radical prostatectomy (RARP) for men with high-risk (HR) prostate cancer (PCa) has not been well studied.Objective
To evaluate the indications for surgical treatment, technical aspects such as nerve sparing (NS) and lymph node dissection (LND), and perioperative outcomes of men with HR PCa treated with RARP.Evidence acquisition
A systematic expert review of the literature was performed in October 2012, searching the Medline, Web of Science, and Scopus databases. Studies with a precise HR definition, robotic focus, and reporting of perioperative and pathologic outcomes were included.Evidence synthesis
A total of 12 papers (1360 patients) evaluating RARP in HR PCa were retrieved. Most studies (67%) used the D’Amico classification for defining HR. Biopsy Gleason grade 8–10 was the most frequent HR identifier (61%). Length of follow-up ranged from 9.7 to 37.7 mo. Incidence of NS varied, although when performed did not appear to compromise oncologic outcomes. Extended LND (ELND) revealed positive nodes in up to a third of patients. The rate of symptomatic lymphocele after ELND was 3%. Overall mean operative time was 168 min, estimated blood loss was 189 ml, length of hospital stay was 3.2 d, and catheterization time was 7.8 d. The 12-mo continence rates using a no-pad definition ranged from 51% to 95% with potency recovery ranging from 52% to 60%. The rate of organ-confined disease was 35%, and the positive margin rate was 35%. Three-year biochemical recurrence–free survival ranged from 45% to 86%.Conclusions
Although the use of RARP for HR PCa has been relatively limited, it appears safe and effective for select patients. Short-term results are similar to the literature on open radical prostatectomy. Variability exists for NS and the template of LND, although ELND improves staging and removes a higher number of metastatic nodes. Further study is required to assess long-term outcomes. 相似文献82.
83.
Purpose
Current surgical approaches for treatment of lumbar canal stenosis are often associated with relatively high rates of reoperation and recurrent stenosis. We have developed a new approach for treatment of this condition: sublaminar-trimming laminoplasty. To describe the surgical approach of sublaminar-trimming laminoplasty and to assess associated outcomes.Methods
Patients with extensive lumbar canal stenosis who received sublaminar-trimming laminoplasty from 2006 to 2008 were considered for inclusion in the study. The surgery comprised aspects of laminotomy and laminectomy. The following were assessed before surgery and 3 years after surgery: leg and back pain by visual analog scale (VAS), extent of disability by Oswestry Disability Index (ODI), severity of back pain by Japanese Orthopedic Association Score for Back Pain (JOA), walking tolerance, and leg numbness. Complications were noted.Results
A total of 49 patients were included in the study (mean age 65.6 ± 10.6 years). VAS leg and back pain, ODI, and JOA scores significantly changed from before surgery to 3 years after surgery (P < 0.001). Mean changes (95 % confidence interval) were ?6.2 (?6.7, ?5.7), ?4.3 (?4.8, ?3.8), ?21.4 (?23.4, ?19.5), and 13.4 (12.1, 14.7) for leg pain, back pain, ODI, and JOA scores, respectively. Patients experienced significant improvements in walking tolerance and leg numbness (P < 0.001). There were no instances of recurrent stenosis or postoperative spinal instability. Complications included intraoperative dural tear (n = 2), postoperative urinary tract infection (n = 2), and inadequate decompression and junctional stenosis during follow-up (both n = 1).Conclusion
Sublaminar-trimming laminoplasty shows promise as an effective treatment for extensive lumbar canal stenosis. 相似文献84.
85.
86.
Directed energy deposition (DED) has been widely used for component repair. In the repair process, the surface defects are machined to a groove or slot and then refilled. The sidewall inclination angle of the groove geometry has been recognized to have a considerable impact on the mechanical properties of repaired parts. The objective of this work was to investigate the feasibility of repairing various V-shaped defects with both experiments and modeling. At first, the repair volume was defined by scanning the defective zone. Then, the repair volume was sliced to generate the repair toolpath. After that, the DED process was used to deposit Ti6Al4V powder on the damaged plates with two different slot geometries. Mechanical properties of the repaired parts were evaluated by microstructure analysis and tensile test. Testing of the repaired parts showed excellent bonding between the deposits and base materials with the triangular slot repair. 3D finite element analysis (FEA) models based on sequentially coupled thermo-mechanical field analysis were developed to simulate the corresponding repair process. Thermal histories of the substrate on the repair sample were measured to calibrate the 3D coupled thermo-mechanical model. The temperature measurements showed very good verification with the predicted temperature results. After that, the validated model was used to predict the residual stresses and distortions in the parts. Predicted deformation and stress results can guide the evaluation of the repair quality. 相似文献
87.
Genghis Khan (Gek) as a putative effector for Drosophila Cdc42 and regulator of actin polymerization 下载免费PDF全文
Liqun Luo Tzumin Lee Linus Tsai Gale Tang Lily Y. Jan Yuh Nung Jan 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(24):12963-12968
The small GTPases Cdc42 and Rac regulate a variety of biological processes, including actin polymerization, cell proliferation, and JNK/mitogen-activated protein kinase activation, conceivably via distinct effectors. Whereas the effector for mitogen-activated protein kinase activation appears to be p65PAK, the identity of effector(s) for actin polymerization remains unclear. We have found a putative effector for Drosophila Cdc42, Genghis Khan (Gek), which binds to Dcdc42 in a GTP-dependent and effector domain-dependent manner. Gek contains a predicted serine/threonine kinase catalytic domain that is 63% identical to human myotonic dystrophy protein kinase and has protein kinase activities. It also possesses a large coiled-coil domain, a putative phorbol ester binding domain, a pleckstrin homology domain, and a Cdc42 binding consensus sequence that is required for its binding to Dcdc42. To study the in vivo function of gek, we generated mutations in the Drosophila gek locus. Egg chambers homozygous for gek mutations exhibit abnormal accumulation of F-actin and are defective in producing fertilized eggs. These phenotypes can be rescued by a wild-type gek transgene. Our results suggest that this multidomain protein kinase is an effector for the regulation of actin polymerization by Cdc42. 相似文献
88.
Mochimaru H Kawamoto M Enomoto T Saitoh Y Abe S Nei T Fukuda Y Kudoh S 《Respirology (Carlton, Vic.)》2008,13(6):863-870
Background and objective: The histological type of intraluminal fibrosis is an important prognostic factor for interstitial pneumonia. We therefore examined whether transbronchial lung biopsy (TBLB) specimens are useful for predicting the clinical course and prognosis of patients with interstitial pneumonia associated with polymyositis and dermatomyositis (PM/DM), with particular attention to the different types of intraluminal fibrosis. Methods: Twenty‐five cases of interstitial pneumonia associated with PM/DM were classified according to the pattern of intraluminal fibrosis as assessed by TBLB, and the clinical course and response to treatment were compared. Interstitial fibrosis was evaluated by sequential thin‐section CT scans. Results: In 19 of 25 (76%) cases, there was sufficient intraluminal fibrosis to perform an evaluation. Intraluminal fibrosis was classified as bud (polyp) type or mural incorporation type (either alone or mixed with bud type). The bud type was seen in five cases and these improved following treatment with corticosteroids only. The mural incorporation type was seen in 14 cases. In 11 of these 14 cases, progressive long‐term fibrosis developed and four cases were fatal, in spite of corticosteroid and immunosuppressive therapy. The response to drugs (P < 0.01) and survival (P < 0.05) were significantly greater in patients with bud‐type than mural incorporation‐type intraluminal fibrosis. Conclusions: Classification of the pattern of intraluminal fibrosis as assessed by TBLB is useful for predicting the response to treatment, clinical course and prognosis of interstitial pneumonia associated with PM/DM. 相似文献
89.
Izumida N Asano Y Doi S Wakimoto H Fukamizu S Kimura T Ueyama T Sakurada H Kawano S Sawanobori T Hiraoka M 《International journal of cardiology》2004,95(2-3):261-268
BACKGROUND: The characteristics of unique ECG findings in the Brugada syndrome have not been well explained. METHODS: To clarify their characteristics and mechanisms, body surface maps (BSM) were recorded from patients with the Brugada syndrome (13 cases; a mean age of 48 years) before and after administration of isoproterenol (ISP) or Na channel blockers (12 cases). RESULTS: ST elevation in V1-V3 was decreased by 0.1 mV or more after ISP infusion in 8 of 11 cases and elevated after Na channel blockers in 8 of 12. In ventricular activation time (VAT) isochronal map, delayed conduction was noted on upper anterior chest in 11 and on anterior left chest in two. Delayed conduction areas were decreased by ISP and expanded by Na channel blockers. QRST isointegral map showed normal findings in baseline with minimal changes after ISP or Na channel blockers. Activation recovery interval (ARI) isochronal map showed prolonged area on upper anterior chest in baseline, being reduced by ISP and expanded by Na channel blockers. ARI dispersion (ARI-d), defined as difference between the maximum and minimum value of ARI, was larger in Brugada patients than that of normal subjects in baseline, and decreased after ISP and increased after Na channel blockers. CONCLUSION: ST elevation in the Brugada syndrome is primarily caused by abnormality in depolarization rather than in repolarization. BSM can provide better information to clarify a mechanism of ECG changes adding its diagnostic value for this unique syndrome. 相似文献
90.
Evidence that the nucleotide exchange and hydrolysis cycle of G proteins causes acute desensitization of G-protein gated inward rectifier K+ channels 下载免费PDF全文
Huai-hu Chuang Mei Yu Yuh Nung Jan Lily Yeh Jan 《Proceedings of the National Academy of Sciences of the United States of America》1998,95(20):11727-11732
The G-protein gated inward rectifier K+ channel (GIRK) is activated in vivo by the Gβγ subunits liberated upon Gi-coupled receptor activation. We have recapitulated the acute desensitization of receptor-activated GIRK currents in heterologous systems and shown that it is a membrane-delimited process. Its kinetics depends on the guanine nucleotide species available and could be accounted for by the nucleotide exchange and hydrolysis cycle of G proteins. Indeed, acute desensitization is abolished by nonhydrolyzable GTP analogues. Whereas regulators of G-protein signaling (RGS) proteins by their GTPase-activating protein activities are regarded as negative regulators, a positive regulatory function of RGS4 is uncovered in our study; the opposing effects allow RGS4 to potentiate acute desensitization without compromising GIRK activation. 相似文献