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81.
82.
SR Kulkarni MS Gohel RA Bulbulia MR Whyman KR Poskitt 《Annals of the Royal College of Surgeons of England》2009,91(3):210-213
INTRODUCTION
Early carotid endarterectomy (CEA) in symptomatic patients may prevent repeat cerebral events. This study investigates the relationship between waiting time for CEA and the incidence of repeat cerebral events prior to surgery in symptomatic patients.PATIENTS AND METHODS
A prospective database of consecutive patients undergoing CEA between January 2002 and December 2006 was reviewed. Repeat event rates prior to surgery were calculated using Kaplan–Meier analysis and predictive factors identified using Cox regression analysis.RESULTS
A total of 118 patients underwent CEA for non-disabling stroke, TIA and amaurosis fugax. Repeat cerebral events occurred in 34 of 118 (29%) patients at a median 51 days (range, 2–360 days) after the first event. The estimated risk of repeat events was 2% at 7 days and 9% at 1 month after first event (Kaplan–Meier survival analysis). Age (HR 1.059; 95% CI 1.014–1.106; P = 0.009] was identified as a predictor of repeat events. Patients underwent surgery at median 97 days (range, 7–621 days) after the first event. Eleven of 60 (18%) patients waiting ≤?97 days for surgery and 23 of 58 (40%) patients waiting >?97 days had repeat events. (P = 0.011, chi-squared test).CONCLUSIONS
Delays in surgery should be reduced in order to minimise repeat cerebral events in patients with symptomatic carotid stenosis, particularly in the elderly population. 相似文献83.
Frank M. Phillips Michael N. Tzermiadianos Leonard I. Voronov Robert M. Havey Gerard Carandang Susan M. Renner David M. Rosler Jorge A. Ochoa Avinash G. Patwardhan 《The spine journal》2009,9(1):96-102
Background contextLumbar fusion is traditionally used to restore stability after wide surgical decompression for spinal stenosis. The Total Facet Arthroplasty System (TFAS) is a motion-restoring implant suggested as an alternative to rigid fixation after complete facetectomy.PurposeTo investigate the effect of TFAS on the kinematics of the implanted and adjacent lumbar segments.Study designBiomechanical in vitro study.MethodsNine human lumbar spines (L1 to sacrum) were tested in flexion-extension (+8 to ?6 Nm), lateral bending (±6 Nm), and axial rotation (±5 Nm). Flexion-extension was tested under 400 N follower preload. Specimens were tested intact, after complete L3 laminectomy with L3–L4 facetectomy, after L3–L4 pedicle screw fixation, and after L3–L4 TFAS implantation. Range of motion (ROM) was assessed in all tested directions. Neutral zone and stiffness in flexion and extension were calculated to assess quality of motion.ResultsComplete laminectomy-facetectomy increased L3–L4 ROM compared with intact in flexion-extension (8.7±2.0 degrees to 12.2±3.2 degrees, p<.05) lateral bending (9.0±2.5 degrees to 12.6±3.2 degrees, p=.09), and axial rotation (3.8±2.7 degrees to 7.8±4.5 degrees p<.05). Pedicle screw fixation decreased ROM compared with intact, resulting in 1.7±0.5 degrees flexion-extension (p<.05), 3.3±1.4 degrees lateral bending (p<.05), and 1.8±0.6 degrees axial rotation (p=.09). TFAS restored intact ROM (p>.05) resulting in 7.9±2.1 degrees flexion-extension, 10.1±3.0 degrees lateral bending, and 4.7±1.6 degrees axial rotation. Fusion significantly increased the normalized ROM at all remaining lumbar segments, whereas TFAS implantation resulted in near-normal distribution of normalized ROM at the implanted and remaining lumbar segments. Flexion and extension stiffness in the high-flexibility zone decreased after facetectomy (p<.05) and increased after simulated fusion (p<.05). TFAS restored quality of motion parameters (load-displacement curves) to intact (p>.05). The quality of motion parameters for the whole lumbar spine mimicked L3–L4 segmental results.ConclusionsTFAS restored range and quality of motion at the operated segment to intact values and restored near-normal motion at the adjacent segments. 相似文献
84.
85.
Avinash Sharma Vinay Kulkarni Saurabh Barde Shrikant Bobade Varun Bhargava Ram Ghodeshwar 《Indian Journal of Thoracic and Cardiovascular Surgery》2009,25(3):118-120
Submitral left ventricular aneurysm is a rare complex disorder, predominently found in African population. We report a case
of a 45 year male diagnosed to have a large submitral aneurysm, eroding the left circumflex artery, leading to severe mitral
regurgitation, severe tricuspid regurgitation and congestive heart failure. Surgical correction comprising of submitral aneurysmorraphy
with Teflon Felt, mitral valve replacement, modified DeVega’s tricuspid annuloplasty and ligation of left distal circumflex
was performed successfully in this case. 相似文献
86.
Monali Gajbhiye Jayendra Kesharwani Avinash Ingle Aniket Gade Mahendra Rai 《Nanomedicine : nanotechnology, biology, and medicine》2009,5(4):382-386
Silver nanoparticles (Ag-NPs) are known to have inhibitory and bactericidal effects. Resistance of fungal infections has emerged in recent years and is a major health problem. Here, we report the extracellular biosynthesis of Ag-NPs using a common fungus, Alternaria alternata. Also in this study, these nanoparticles were evaluated for their part in increasing the antifungal activity of fluconazole against Phoma glomerata, Phoma herbarum, Fusarium semitectum, Trichoderma sp., and Candida albicans. The antifungal activity of fluconazole was enhanced against the test fungi in the presence of Ag-NPs. Fluconazole in combination with Ag-NPs showed the maximum inhibition against C. albicans, which was confirmed from the increase in fold area of inhibition, followed by P. glomerata and Trichoderma sp., which showed less increase in the fold area, whereas no significant enhancement of activity was found against P. herbarum and F. semitectum.From the Clinical EditorThe antifungal activity of fluconazole was enhanced in presence of silver nanoparticles against the test fungi. Fluconazole in combination with Ag-NPs showed the maximum inhibition against C. albicans, followed by P. glomerata and Trichoderma sp. No significant enhancement of activity was found against P. herbarum and F. semitectum. 相似文献
87.
Thomas AB Chavan UB Nanda RK Kothapalli LP Deshpande AD Jagdale SN Dighe SB 《Hindustan antibiotics bulletin》2009,51(1-4):33-38
Two simple, accurate and reproducible spectrophotometric methods have been developed for the simultaneous estimation of Hydrochlorothiazide (Hctz), Atenolol (Atn) and Losartan potassium (Los) in combined tablet dosage forms. The first method involves determination using the simultaneous equation method, the sampling wavelengths selected are, 272.5 nm, 224 nm and 250 nm over the concentration ranges of 0.5-30 microg/ml, 1-50 microg/ ml and 1-60 microg/ml for Hctz, Atn and Los respectively. The second method is the First order derivative method, the sampling wavelengths selected for estimation of Hctz, Atn and Los are 280.5 nm, 233 nm and 244 nm with linearity in the concentration ranges of 0.5-30 microg/ ml, 1-50 microg/ml and 1-60 microg/ml respectively. The results of the analysis were validated statistically and recovery studies were carried out as per ICH guidelines. 相似文献
88.
89.
Asha Byju Thomas Shrikrushna Digambar Patil Rabindra Kumar Nanda Lata Prasad Kothapalli Shital Shridhar Bhosle Avinash Devidas Deshpande 《Saudi Pharmaceutical Journal》2011,19(4):221-231
A stability indicating high performance thin layer chromatography (HPTLC) method was developed and validated for determination of two anti-diabetic drugs, nateglinide and metformin hydrochloride in co-formulations. Study was performed on pre-coated silica gel HPTLC plates using chloroform:ethyl acetate:acetic acid (4:6:0.1 v/v/v) as the mobile phase. A TLC scanner set at 216 nm was used for direct evaluation of the chromatograms in the reflectance/absorbance mode. Method was validated according to ICH guidelines. The correlation coefficients of calibration curves were found to be 0.996 and 0.995 in the concentration range of 200–2400 and 500–3000 ng band−1 for nateglinide and metformin, respectively. The method had an accuracy of 99.72% for nateglinide and 100.08% for metformin hydrochloride. The method had the potential to determine these drugs simultaneously from dosage forms without any interference of the tablets excipients. Nateglinide and metformin hydrochloride were also subjected to acid, base, oxidation, wet, heat and photo-degradation studies. The degradation products obtained were well resolved from the pure drugs with significantly different Rf values. As the method could effectively separate the drugs from its degradation products, it can be used for stability-indicating analysis. 相似文献
90.
Selection of replicon variants resistant to ACH-806, a novel hepatitis C virus inhibitor with no cross-resistance to NS3 protease and NS5B polymerase inhibitors 下载免费PDF全文
Yang W Zhao Y Fabrycki J Hou X Nie X Sanchez A Phadke A Deshpande M Agarwal A Huang M 《Antimicrobial agents and chemotherapy》2008,52(6):2043-2052
We have discovered a novel class of compounds active against hepatitis C virus (HCV), using a surrogate cellular system, HCV replicon cells. The leading compound in the series, ACH-806 (GS-9132), is a potent and specific inhibitor of HCV. The selection of resistance replicon variants against ACH-806 was performed to map the mutations conferring resistance to ACH-806 and to determine cross-resistance profiles with other classes of HCV inhibitors. Several clones emerged after the addition of ACH-806 to HCV replicon cells at frequencies and durations similar to that observed with NS3 protease inhibitors and NS5B polymerase inhibitors. Phenotypic analyses of these clones revealed that they are resistant to ACH-806 but remain sensitive to other classes of HCV inhibitors. Moreover, no significant change in the susceptibility to ACH-806 was found when the replicon cellular clones resistant to NS3 protease inhibitors and NS5B polymerase inhibitors were examined. Sequencing of the entire coding region of ACH-806-resistant replicon variants yielded several consensus mutations. Reverse genetics identified two single mutations in NS3, a cysteine-to-serine mutation at amino acid 16 and an alanine-to-valine mutation at amino acid 39, that are responsible for the resistance of the replicon variants to ACH-806. Both mutations are located at the N terminus of NS3 where extensive interactions with the central hydrophobic region of NS4A exist. These data provide evidence that ACH-806 inhibits HCV replication by a novel mechanism. 相似文献