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101.
Perugia G Ciccariello M Pirolli F Chinazzi A Teodonio S Borgoni G Croce F Liberti M 《Urology》2012,79(4):e51-e52
Paraurethral leiomyoma is a rare, benign, hormone-dependent neoplasm of mesenchymal origin affecting women. The clinical evidence varies, but it tends to be asymptomatic or associated with the sensation of a foreign body; urinary symptoms are rarely described. The distinction among urethral, paraurethral, and anterior vaginal wall leiomyoma can be very difficult owing to their anatomic proximity. Excision of the mass is the recommended treatment, and the diagnosis is confirmed by the pathologic finding to rule out the presence of a sarcoma. A case of paraurethral leiomyoma associated with dysuria, dyspareunia, and obstructive voiding symptoms is reported. 相似文献
102.
Bello L Lucini V Giussani C Carrabba G Pluderi M Scaglione F Tomei G Villani R Black PM Bikfalvi A Carroll RS 《Neurosurgery》2003,52(1):177-85; discussion 185-6
OBJECTIVE: The biological features of malignant gliomas include high cell proliferation, extensive local infiltration of tumor cells into normal brain, and marked neovascularization. alphavbeta3 integrin is highly expressed in malignant gliomas and plays a role in glioma growth. This article investigates the in vitro and in vivo effects of a synthetic alphavbeta3 integrin inhibitor called IS20I on human malignant gliomas. METHODS: The in vitro effects of IS20I were studied by performing adhesion assays, competition studies, semi-in vivo angiogenic assays, and migration and proliferation assays. For the in vivo experiments, IS20I was administered systemically in nude mouse intracranial and subcutaneous malignant glioma models. RESULTS: IS20I reacted selectively to alphavbeta3 integrin in glioma cells and tissues. In vitro, IS20I strongly inhibited angiogenesis and simultaneously exhibited potent antimitotic and antimigratory effects on numerous tumor and endothelial cell lines. In addition, at high concentrations, IS20I induced endothelial and tumor cell apoptosis. In vivo, when IS20I was administered intraperitoneally in subcutaneous and intracranial nude mouse glioma models, it potently reduced malignant glioma growth. Inhibition levels of 76 and 82% were observed at concentrations of 1 and 5 mg/kg, respectively, in the U87 intracranial model. The suppression of tumor growth is associated with a decrease in tumor vascularity, an increase in apoptosis, and a decrease in tumor cell proliferation. CONCLUSION: This work expands the understanding of the effects of anti-alphavbeta3 integrin inhibitors on malignant gliomas. In addition to direct proapoptotic and antiangiogenic effects, IS20I inhibits tumor and endothelial cell proliferation and migration, resulting in a potent inhibition of glioma growth in vivo. 相似文献
103.
Bellantone R Lombardi CP Bossola M Boscherini M De Crea C Alesina P Traini E Princi P Raffaelli M 《World journal of surgery》2002,26(12):1468-1471
Total thyroidectomy is not frequently performed in cases of benign disease because of the associated risk of postoperative hypoparathyroidism and recurrent laryngeal nerve (RLN) damage. We chose a series of patients who had undergone total thyroidectomy (TT) for benign thyroid tumors to evaluate the safety of this approach and its role in the treatment of nonmalignant lesions of the thyroid. We considered only patients with a minimum follow-up of 24 months. Records of 526 patients who underwent TT were carefully reviewed, assessing for perioperative complications and late sequelae. The mean age was 44 +/- 15.7 years; 109 patients (20.7%) were male and 417 (79.3%) were female. Altogether, 65 patients (12.3%) were operated on for toxic goiter, 429 (81.6%) for bilateral nodular goiter, and 32 (6.1%) for thyroiditis. Postoperative hemorrhage requiring reoperation occurred in 8 cases (1.5%). The incidences of permanent RLN palsy (considered as a percentage of the nerves at risk) and permanent hypocalcemia were 0.4% and 3.4%, respectively. A trend toward a decrease in the complication rate was observed during the last 5 years. There were no disease recurrences during a mean follow-up of 44 months. The results of our series show that TT can be performed safely in patients, with a low incidence of lifetime disabilities. TT has the advantage of reducing/avoiding the risk of disease recurrence and reoperation and should therefore be considered a valuable option for treating benign thyroid diseases. 相似文献
104.
Background: When investigating the degree of formation of intimal hyperplasia (IH) quantification of the extent of the lesion is crucial to its assessment and analysis. The aim of the present study was to establish a new methodology (IH index) for estimating the degree of IH associated with vascular prosthesis implantation. Methods: Ten female Merino sheep underwent a standard gelatin sealed Dacron (GSD) patch grafting procedure in the left common carotid artery. The grafts were harvested 4 weeks following implantation and processed for assessment of IH by two methodologies ? mean intimal thickness (MIT) and IH index. The advantages and disadvantages of the two methods for expressing the degree of IH were compared. Results: The IH index is less labour intensive but is as accurate as the MIT method in quantifying the IH lesion, statistical analysis showing high correlation and measurement agreement between the two methods. Conclusion: The IH index is a labour saving standardized methodology for quantification of IH in the current animal model. 相似文献
105.
Cristiano Cervellera Mauro Gaggero Danilo Macciò 《Optimal control applications & methods.》2017,38(6):1193-1207
This paper investigates the use of lattice point sets as an efficient method to sample uniformly the state space of discrete‐time dynamic systems for the solution of finite‐horizon optimal control problems using approximate dynamic programming. Lattice point sets are a kind of discretization method, commonly employed for efficient numerical integration, providing a regular and balanced sampling of the state space based on the repetition of elementary unit cells. A convergence analysis of the approximate solution of the control problem to the optimal one is provided, pointing out that such sampling schemes allow one to efficiently exploit possible regularities of the cost‐to‐go functions. Furthermore, it is shown that a higher accuracy may be obtained through suitable transformations of the state vector of the dynamic system. Another advantage of lattice point sets over other sampling schemes is the possibility of evaluating a priori the goodness of a given set over another through the explicit computation of a specific parameter. Simulation results concerning the optimal control of a water reservoirs system are presented to show the effectiveness of the proposed approach. 相似文献
106.
107.
Bustamante M Hasler U Leroy V de Seigneux S Dimitrov M Mordasini D Rousselot M Martin PY Féraille E 《Journal of the American Society of Nephrology : JASN》2008,19(1):109-116
Recent evidence suggests that arginine vasopressin (AVP)-dependent aquaporin-2 expression is modulated by the extracellular calcium-sensing receptor (CaSR) in principal cells of the collecting duct, but the signaling pathways mediating this effect are unknown. Using a mouse cortical collecting duct cell line (mpkCCD(cl4)), we found that increasing the concentration of apical extracellular calcium or treating with the CaSR agonists neomycin or Gd(3+) attenuated AVP-dependent accumulation of aquaporin-2 mRNA and protein; CaSR gene-silencing prevented this effect. Calcium reduced the AVP-induced accumulation of cAMP, but this did not occur by increased degradation of cAMP by phosphodiesterases or by direct inhibition of adenylate cyclase. Notably, the effect of extracellular calcium on AVP-dependent aquaporin-2 expression was prevented by inhibition of calmodulin. In summary, our results show that high concentrations of extracellular calcium attenuate AVP-induced aquaporin-2 expression by activating the CaSR and reducing coupling efficiency between V(2) receptor and adenylate cyclase via a calmodulin-dependent mechanism in cultured cortical collecting duct cells. 相似文献
108.
Continuous Metabolic Monitoring in Infant Cardiac Surgery: Toward an Individualized Cardiopulmonary Bypass Strategy 下载免费PDF全文
Salvatore Torre Elisa Biondani Tiziano Menon Diego Marchi Mauro Franzoi Daniele Ferrarini Rocco Tabbì Stiljan Hoxha Luca Barozzi Giuseppe Faggian Giovanni Battista Luciani 《Artificial organs》2016,40(1):65-72
Cardiopulmonary bypass (CPB) in infants is associated with morbidity due to systemic inflammatory response syndrome (SIRS). Strategies to mitigate SIRS include management of perfusion temperature, hemodilution, circuit miniaturization, and biocompatibility. Traditionally, perfusion parameters have been based on body weight. However, intraoperative monitoring of systemic and cerebral metabolic parameters suggest that often, nominal CPB flows may be overestimated. The aim of the study was to assess the safety and efficacy of continuous metabolic monitoring to manage CPB in infants during open‐heart repair. Between December 2013 and October 2014, 31 consecutive neonates, infants, and young children undergoing surgery using normothermic CPB were enrolled. There were 18 male and 13 female infants, aged 1.4 ± 1.7 years, with a mean body weight of 7.8 ± 3.8 kg and body surface area of 0.39 m2. The study was divided into two phases: (i) safety assessment; the first 20 patients were managed according to conventional CPB flows (150 mL/min/kg), except for a 20‐min test during which CPB was adjusted to the minimum flow to maintain MVO2 >70% and rSO2 >45% (group A); (ii) efficacy assessment; the following 11 patients were exclusively managed adjusting flows to maintain MVO2 >70% and rSO2 >45% for the entire duration of CPB (group B). Hemodynamic, metabolic, and clinical variables were compared within and between patient groups. Demographic variables were comparable in the two groups. In group A, the 20‐min test allowed reduction of CPB flows greater than 10%, with no impact on pH, blood gas exchange, and lactate. In group B, metabolic monitoring resulted in no significant variation of endpoint parameters, when compared with group A patients (standard CPB), except for a 10% reduction of nominal flows. There was no mortality and no neurologic morbidity in either group. Morbidity was comparable in the two groups, including: inotropic and/or mechanical circulatory support (8 vs. 1, group A vs. B, P = 0.07), reexploration for bleeding (1 vs. none, P = not significant [NS]), renal failure requiring dialysis (none vs. 1, P = NS), prolonged ventilation (9 vs. 4, P = NS), and sepsis (2 vs. 1, P = NS). The present study shows that normothermic CPB in neonates, infants, and young children can be safely managed exclusively by systemic and cerebral metabolic monitoring. This strategy allows reduction of at least 10% of predicted CPB flows under normothermia and may lay the ground for further tailoring of CPB parameters to individual patient needs. 相似文献
109.
Mauro Spina Giacomo Sabbioni Domenico Tigani 《La Chirurgia degli Organi di Movimento》2008,92(3):175-178
Meniscal cysts are a rare disease constantly combined with a horizontal meniscal lesion. Currently, nuclear magnetic resonance
(MRI) is the main diagnostic tool, because of its high sensitivity and specificity, and decompression arthroscopy combined
with selective meniscectomy is the treatment of choice. The Authors report a case of a voluminous medial meniscal cyst where
instrumental examination, MRI, was fundamental for the preoperative diagnosis of the horizontal meniscal lesion causing the
cystic degeneration of the meniscus. The treatment performed was selective meniscectomy of the body and posterior horn of
the medial meniscus and decompression of the voluminous cyst by arthroscopy. Physical examination after six months showed
the complete resolution of swelling at the medial hemirima, no walking pain and normal range of motion. 相似文献
110.
Multiple reports advocate the use of infrapopliteal angioplasty for limb salvage; however, its utility in the setting of renal
failure is unclear. We performed angioplasty, rather than bypass, for tibial stenoses or occlusions <3 cm on 90 limbs of 79
patients (64.4% male, mean age 67.2 years), all with ischemic ulcer. Seventy (77.8%) had diabetes mellitus and 16 (17.8%)
had end-stage renal disease (ESRD). Mean follow-up was 14.3 months (range 0.3-45). Associated femoropopliteal revascularization
was required in 28 (31.0%) limbs. Primary angiographic success was achieved in 83 (92.2%) limbs. Residual stenosis or thrombosis
occurred in two and five limbs, respectively. Dissection occurred in six limbs, all successfully treated with stent placement.
Ulcer healing occurred after initial angioplasty in 41 (55.4%) non-ESRD and four (25%) ESRD limbs. Subsequent revascularization
procedures were required in 21 (23.3%) limbs, including six bypasses and 15 repeat angioplasties, of which three underwent
subsequent bypasses. Major amputation was required in 11 (14.9%) non-ESRD and seven (43.7%) ESRD limbs. Limb salvage was 84.4%
and 80.2% in those without and 52.5% and 52.5% in those with ESRD at 1 and 3 years, respectively (p = 0.01). Thirty-day mortality was 2.2%. Overall actuarial survival was 82.2% and 62.1% at 1 and 3 years, respectively, and
did not differ significantly between patients with and without ESRD (p = 0.66). Infrapopliteal angioplasty is a safe technique with low procedural morbidity and mortality. However, the inferior
wound-healing and limb-salvage rates observed in patients with renal failure bring to question the utility of infrapopliteal
angioplasty in this population.
Presented at the Fifteenth Annual Winter Meeting of the Peripheral Vascular Surgery Society, Steamboat Springs, CO, January
28-30, 2005. 相似文献