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排序方式: 共有816条查询结果,搜索用时 15 毫秒
91.
Rajeev Fernando Ketan Koranne Pranav Loyalka Biswajit Kar Igor Gregoric 《Experimental & Clinical Cardiology》2013,18(1):e50-e54
The ductus arteriosus originates from the persistence of the distal portion of the left sixth aortic arch. It connects the descending aorta (immediately distal to the left subclavian artery) to the roof of the main pulmonary artery, near the origin of the left pulmonary artery. Persistence of the duct beyond 48 h after birth is abnormal and results in patent ductus arteriosus (PDA). PDA is rare in adults because it is usually discovered and treated in childhood. Mechanical closure remains the definitive therapy because the patency of ductus arteriosus may lead to multiple complications, depending on the size and flow through the ductus. PDA closure is indicated in patients with symptoms and evidence of left heart enlargement, and in patients with elevated pulmonary pressures when reversal is possible. Transcatheter closure is the preferred technique in adults because it avoids sternotomy, reduces the length of hospital stay and is associated with fewer complications compared with surgery. First demonstrated in 1967, both the technique and the occluder devices used have since evolved. However, designing an ideal PDA occluder has been a challenge due to the variability in size, shape and orientation of PDAs. The present article describes a case involving a 35-year-old woman who presented to the Center for Advanced Heart Failure (Houston, USA) with congestive heart failure due to a large PDA, which was successfully occluded using an Amplatzer (St Jude Medical, USA) muscular ventricular septal defect closure device. The wider waist and dual-retention discs of these ventricular septal defect closure devices may be important factors to consider in the future development of devices for the occlusion of large PDAs. 相似文献
92.
1 引言
弹簧圈栓塞最初被设计并经美国食品药品监督管理局批准用于治疗显微外科手术夹闭风险高的脑动脉瘤,但目前该方法越来越被认为是颅内动脉瘤的一线治疗方法.动脉瘤血管内治疗技术已有长足进步,新器材的研发使得以前因血管解剖结构复杂而无法填塞的动脉瘤也得以治疗,从而扩大了血管内治疗的适应证.而且,血管内弹簧圈栓塞已成为当前动脉瘤血管内治疗的主流方法;医学文献证明,在特定患者人群中,弹簧圈栓塞的转归优于外科手术夹闭[1-3].最近的一份美国心脏协会(American Heart Association,AHA)科学声明指出,对于适合治疗的脑动脉瘤,不论是血管内栓塞还是显微外科手术夹闭,均为破裂动脉瘤Ⅰ级推荐治疗方法和未破裂动脉瘤的Ⅱa级推荐治疗方法[4].在这两组患者中,治疗利大于弊.一个在血管显微神经外科、神经重症监护和介入神经外科方面有着丰富经验的多学科团队最有利于对颅内动脉瘤的处理实施最佳的技术.神经血管联合写作组此前已发表过一份联合声明,提出了有关脑血管介入治疗的培训和认证的推荐意见[5]. 相似文献
93.
Ketan L Vora Graham Buckton David Clapham 《European journal of pharmaceutical sciences》2004,22(2-3):97-105
This study was undertaken to see if the combined technique of DVS-NIR could add to the understanding of transitions between physical forms of theophylline. There was excellent correlation between the mass changes and the intensity of the NIR peaks, showing that the hydrate was being formed and lost. This was characterised by the peaks at 1478 and 1972 nm representing an -OH deformation. NIR spectra for desorption shows that the dehydrate retains partial structure of both the anhydrate and hydrate crystal lattices. During rehydration of the dehydrate a new transition was discovered. An unexpected mass loss occurred between 40 and 50% RH. Usually, a mass loss during water sorption is characteristic of crystallisation of an amorphous material, although in this case it could be that the sample is crystalline. NIR data showed that during this transition the dehydrate peaks reverted back to the peak positions seen for anhydrous theophylline. The absorption of water into the dehydrate allowed the freedom of movement for the stable anhydrous lattice to form. It was concluded that DVS-NIR is a useful tool to study solid-state transitions and that the transition exists for conversion of theophylline dehydrate to anhydrate which is facilitated through water sorption. 相似文献
94.
Trimurti D Nadkarni Ram Kumar Menon Ketan I Desai Atul Goel 《Journal of clinical neuroscience》2006,13(2):285-288
A 52-year-old man presented with low backache, paraesthesiae and spasticity of both lower limbs. He had urinary retention and constipation. Investigations revealed a vascular intradural cauda equina-conus tumor. MRI scan demonstrated an enhancing mass at the second and third lumbar vertebral levels. There were multiple dilated and tortuous veins draining from both poles of the tumor. Digital subtraction spinal angiogram showed the tumor to be supplied mainly by the radiculo-medullary artery from first lumbar artery and dural branches of the second and third lumbar arteries. At surgery, after pre-operative embolization, a well-defined tumor with an orange hue and fleshy consistency was encountered arising from the filum terminale. The tumor was excised en bloc. A sporadic hemangioblastoma arising from the filum terminale should be considered as a rare cause of back pain and sciatica. Total excision of the tumor offers cure. 相似文献
95.
96.
Intravitreal bevacizumab treatment of choroidal neovascularization secondary to age-related macular degeneration 总被引:25,自引:0,他引:25
Spaide RF Laud K Fine HF Klancnik JM Meyerle CB Yannuzzi LA Sorenson J Slakter J Fisher YL Cooney MJ 《Retina (Philadelphia, Pa.)》2006,26(4):383-390
PURPOSE: To describe the short-term anatomical and visual acuity responses after intravitreal injection of bevacizumab (Avastin, Genentech) in patients with choroidal neovascularization (CNV) secondary to age-related macular degeneration (AMD). METHODS: We conducted a retrospective study of patients with CNV secondary to AMD who were treated with intravitreal injection of bevacizumab (1.25 mg) during a 3-month period. Patients underwent best-corrected Snellen visual acuity testing, optical coherence tomography, and ophthalmoscopic examination at baseline and follow-up visits. RESULTS: There were 266 consecutive eyes of 266 patients who received injections, and follow-up information was available for 251 (94.4%). The mean age of the patients was 80.3 years, the mean baseline visual acuity was 20/184, and 175 (69.7%) had inadequate response to alternate methods of treatment. At the 1-month follow-up (data available for 244 patients), the mean visual acuity was 20/137 (P < 0.001 as compared with baseline), and 74 (30.3%) of patients had improvement in visual acuity as defined by a halving of the visual angle. At the 2-month follow-up (data available for 222 patients), the mean visual acuity was 20/122 (P < 0.001), and 78 (31.1%) of patients had visual improvement. At the 3-month follow-up (data available for 141 patients), the mean visual acuity was 20/109 (P < 0.001), and 54 (38.3%) of patients had visual acuity improvement. The mean central macular thickness at baseline was 340 mum and decreased to a mean of 247 microm at month 1 (P < 0.001) and 213 microm at month 3 (P < 0.001). At 1 month, two patients had mild vitritis, as did one patient at 2 months, who had a history of recurrent uveitis. No endophthalmitis, increased intraocular pressure, retinal tear, or retinal detachment occurred. The risk for thromboembolic disorders did not seem to be different than reported previously in studies concerning macular degeneration. CONCLUSION: There were no apparent short-term safety concerns for intravitreal bevacizumab injection for CNV. Treated eyes had a significant decrease in macular thickness and improvement in visual acuity. The follow-up was too short to make any specific treatment recommendations, but the favorable short-term results suggest further study is needed. 相似文献
97.
DNA methylation changes after 5-aza-2'-deoxycytidine therapy in patients with leukemia 总被引:3,自引:0,他引:3
Yang AS Doshi KD Choi SW Mason JB Mannari RK Gharybian V Luna R Rashid A Shen L Estecio MR Kantarjian HM Garcia-Manero G Issa JP 《Cancer research》2006,66(10):5495-5503
5-Aza-2'-deoxycytidine (decitabine) is postulated to have clinical activity in myeloid leukemias via its ability to inhibit DNA methylation. To study this, we examined DNA methylation in patients with leukemia treated with decitabine. Five days after the treatment, total genomic 5-methylcytosine/cytosine decreased on average by 14% (from 4.3% to 3.7%), whereas methylation of repetitive DNA elements showed a mean decrease of 9% and 16% for Alu and long interspersed nucleotide elements, respectively. Methylation decreased linearly with increasing doses between 5 and 20 mg/m(2)/d (r = 0.88; P = 0.05) but showed a plateau above that. Hypomethylation correlated with response in patients with acute myelogenous leukemia treated with low doses (5-20 mg/m(2)/d), but patients with chronic myelogenous leukemia treated with high doses (100-180 mg/m(2)/d) showed no such correlation. Aberrant methylation of p15 (>10%) was found in 27% of patients, and 80% of these showed a decrease by at least one third, but this did not correlate with response. The imprinted gene H19 showed little change in methylation after decitabine. In conclusion, we show dose-dependent hypomethylation after decitabine at low doses. Increasing the dose, which has been shown previously to result in a reduced response rate, was not accompanied by further hypomethylation. 相似文献
98.
Badani KK Hemal AK Fumo M Kaul S Shrivastava A Rajendram AK Yusoff NA Sundram M Woo S Peabody JO Mohamed SR Menon M 《World journal of urology》2006,24(2):198-201
Percutaneous nephrolithotomy (PCNL) remains the treatment of choice for staghorn renal calculi. Many reports suggest that laparoscopy can be an alternative treatment for large renal stones. We wished to evaluate the role and feasibility of laparoscopic extended pyelolithotomy (REP) for treatment of staghorn calculi. Thirteen patients underwent REP for treatment of staghorn calculi over a 12-day period. Twelve patients had partial staghorn stones and one had a complete staghorn stone. All patients had pre-operative and post-operative imaging including KUB and computed tomography. All procedures were completed robotically without conversion to laparoscopy or open surgery. Mean operative time was 158 min and mean robotic console time was 108 min. Complete stone removal was accomplished in all patients except the one with a complete staghorn calculus. Estimated blood loss was 100 cc, and no patient required post-operative transfusion. REP is an effective treatment alternative to PCNL in some patients with staghorn calculi. However, patients with complete staghorn stones are not suitable candidates for this particular technique. 相似文献
99.
Cheng TY Sheth K White RR Ueno T Hung CF Clary BM Pappas TN Tyler DS 《Annals of surgical oncology》2006,13(1):66-74
Background Neoadjuvant chemoradiotherapy (neo-CRT) is being used with increasing frequency for periampullary tumors, but how it alters
the complication rate of pancreaticoduodenectomy (PD) is unclear.
Methods A retrospective analysis was conducted of 79 patients with periampullary malignancies who received 5-fluorouracil–based neo-CRT
followed by PD.
Results There was no difference in mortality between PD after neo-CRT (3.8%) and conventional PD for either malignant (4.5%) or benign
(2.2%) disease. Focusing only on patients with malignancy, the neo-CRT group had a significantly lower pancreatic leak rate
than the conventional group (10% vs. 43%; P < .001). Intra-abdominal abscesses were less common in the neo-CRT group (8.8% vs. 21%; P = .019), and there was one (1.2%) amylase-rich abscess in neo-CRT group, compared with eight (12%) in the conventional group.
In addition, two patients in the conventional group died of leak-associated sepsis, compared with none in the neo-CRT group.
Multivariate analysis revealed that neoadjuvant chemoradiation (odds ratio, .15) was the most significant factor associated
with a reduced risk of pancreatic leak.
Conclusions Neo-CRT does not increase the mortality or morbidity of PD. In contrast, neo-CRT was associated with a marked reduction in
the incidence of pancreatic leak, as well as leak-associated morbidity and mortality. 相似文献
100.
Nie Z Perretta C Lu J Su Y Margosiak S Gajiwala KS Cortez J Nikulin V Yager KM Appelt K Chu S 《Journal of medicinal chemistry》2005,48(5):1596-1609
Fatty acid biosynthesis is essential for bacterial survival. Components of this biosynthetic pathway have been identified as attractive targets for the development of new antibacterial agents. FabH, beta-ketoacyl-ACP synthase III, is a particularly attractive target, since it is central to the initiation of fatty acid biosynthesis and is highly conserved among Gram-positive and -negative bacteria. Small molecules that inhibit FabH enzymatic activity have the potential to be candidates within a novel class of selective, nontoxic, broad-spectrum antibacterials. Using crystallographic structural information on these highly conserved active sites and structure based drug design principles, a benzoylaminobenzoic acid series of compounds was developed as potent inhibitors of FabH. This inhibitor class demonstrates strong antibacterial activity against Gram-positive and selected Gram-negative organisms. 相似文献