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71.
72.
Deterioration of motor neurons due to amyotrophic lateral sclerosis (ALS) would affect the strides from one gait cycle to
the next. Computer-assisted techniques are useful for gait analysis, and also have high potential in quantitatively monitoring
the pathological progression. In this paper, we applied the signal turns count method to measure the fluctuations in the swing-interval
time series recorded from 16 healthy control subjects and 13 patients with ALS. The swing-interval turns count (SWITC) parameter
derived with the threshold of 0.06 s presented a significant difference (p < 0.001) between the healthy control subjects and ALS patients. Besides the SWITC, we also computed the averaged stride interval
(ASI), which is usually longer in the patient with ALS (p < 0.0001), to characterize the gait patterns of ALS patients. In the pattern classification experiments, the Fisher’s linear
discriminant analysis (FLDA) and the least squares support vector machine (LS-SVM), both input with the SWITC and ASI features,
were evaluated using the leave-one-out cross-validation method. The results showed that the LS-SVM with sigmoid kernels was
able to provide a classification accurate rate of 89.66% and an area of 0.9629 under the receiver operating characteristic
(ROC) curve, which were superior to those obtained with the linear classifier in the form of FLDA. 相似文献
73.
P.A.N. Chandraratna M.D. F.R.C.P. Ranil Gajanayaka M.D. Surendra M. Makkena M.D. Kanishka Wijegunaratne B.S. Haroon Hafeez Sridhar Vijayasekaran M.D. Asghar Ali M.D. 《Echocardiography (Mount Kisco, N.Y.)》2010,27(5):563-566
Background: Echocardiographic imaging using a handheld transducer in conjunction with treadmill exercise testing is commonly used for the diagnosis of coronary artery disease. Motion of the hand and the transducer during peak exercise preclude optimal imaging. To circumvent the limitations of handheld transducers, we developed a low profile transducer (CONTISON) which can be attached to the chest wall for continuous cardiac imaging. Methods and Results: This feasibility study was performed in 10 normal male subjects (28 to 36 years). The ultrasound transducer was placed in the third or fourth intercostal space at the left sternal border to permit imaging of the left ventricle in its short axis. The transducer was interfaced with a commercially available ultrasound machine. The left ventricle was imaged at rest and while subjects exercised according to a standard Bruce protocol. All segments of the left ventricular short axis were seen at rest and peak exercise. Increased left ventricular wall thickening and wall motion were seen at peak exercise. There were no complications from the procedure. Conclusion: We demonstrated the feasibility of hands‐free left ventricular imaging during treadmill exercise using the CONTISON transducer. Further evaluation of the technique to detect stress‐induced wall motion abnormalities, as a means of diagnosing myocardial ischemia, appears warranted. (ECHOCARDIOGRAPHY 2010;27:563‐566) 相似文献
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75.
Oxaliplatin pharmacokinetics and pharmacodynamics in adult cancer patients with impaired renal function. 总被引:1,自引:0,他引:1
Chris H Takimoto Martin A Graham Graham Lockwood Chee M Ng Andrew Goetz Dennis Greenslade Scot C Remick Sunil Sharma Sridhar Mani Ramesh K Ramanathan Timothy W Synold James H Doroshow Anne Hamilton Daniel L Mulkerin Percy Ivy Merrill J Egorin Jean L Grem 《Clinical cancer research》2007,13(16):4832-4839
PURPOSE: To characterize the pharmacokinetics and pharmacodynamics of oxaliplatin in cancer patients with impaired renal function. EXPERIMENTAL DESIGN: Thirty-four patients were stratified by 24-h urinary creatinine clearance (CrCL) into four renal dysfunction groups: group A (control, CrCL, >or=60 mL/min), B (mild, CrCL, 40-59 mL/min), C (moderate, CrCL, 20-39 mL/min), and D (severe, CrCL, <20 mL/min). Patients were treated with 60 to 130 mg/m2 oxaliplatin infused over 2 h every 3 weeks. Pharmacokinetic monitoring of platinum in plasma, plasma ultrafiltrates, and urine was done during cycles 1 and 2. RESULTS: Plasma ultrafiltrate platinum clearance strongly correlated with CrCL (r2 = 0.712). Platinum elimination from plasma was triphasic, and maximal platinum concentrations (Cmax) were consistent across all renal impairment groups. However, only the beta-half-life was significantly prolonged by renal impairment, with values of 14.0 +/- 4.3, 20.3 +/- 17.7, 29.2 +/- 29.6, and 68.1 h in groups A, B, C, and D, respectively (P = 0.002). At a dose level of 130 mg/m2, the area under the concentration time curve increased in with the degree of renal impairment, with values of 16.4 +/- 5.03, 39.7 +/- 11.5, and 44.6 +/- 14.6 mug.h/mL, in groups A, B, and C, respectively. However, there was no increase in pharmacodynamic drug-related toxicities. Estimated CrCL using the Cockcroft-Gault method approximated the measured 24-h urinary CrCL (mean prediction error, -5.0 mL/min). CONCLUSIONS: Oxaliplatin pharmacokinetics are altered in patients with renal impairment, but a corresponding increase in oxaliplatin-related toxicities is not observed. 相似文献
76.
Mutation and Methylation Analysis of the Chromodomain-Helicase-DNA Binding 5 Gene in Ovarian Cancer 下载免费PDF全文
Kylie L Gorringe David YH Choong Louise H Williams Manasa Ramakrishna Anita Sridhar Wen Qiu Jennifer L Bearfoot Ian G Campbell 《Neoplasia (New York, N.Y.)》2008,10(11):1253-1258
Chromodomain, helicase, DNA binding 5 (CHD5) is a member of a subclass of the chromatin remodeling Swi/Snf proteins and has recently been proposed as a tumor suppressor in a diverse range of human cancers. We analyzed all 41 coding exons of CHD5 for somatic mutations in 123 primary ovarian cancers as well as 60 primary breast cancers using high-resolution melt analysis. We also examined methylation of the CHD5 promoter in 48 ovarian cancer samples by methylation-specific single-stranded conformation polymorphism and bisulfite sequencing. In contrast to previous studies, no mutations were identified in the breast cancers, but somatic heterozygous missense mutations were identified in 3 of 123 ovarian cancers. We identified promoter methylation in 3 of 45 samples with normal CHD5 and in 2 of 3 samples with CHD5 mutation, suggesting these tumors may have biallelic inactivation of CHD5. Hemizygous copy number loss at CHD5 occurred in 6 of 85 samples as assessed by single nucleotide polymorphism array. Tumors with CHD5 mutation or methylation were more likely to have mutation of KRAS or BRAF (P = .04). The aggregate frequency of CHD5 haploinsufficiency or inactivation is 16.2% in ovarian cancer. Thus, CHD5 may play a role as a tumor suppressor gene in ovarian cancer; however, it is likely that there is another target of the frequent copy number neutral loss of heterozygosity observed at 1p36. 相似文献
77.
A C Vitug R A Lopchinsky S Sridhar M F Wheeler J M Goldman 《Archives of otolaryngology (1960)》1985,111(5):340-341
A patient was seen with a thyroid cyst. Fine- and core-needle biopsies revealed no evidence of tumor. A thyroid cyst lined by malignant squamous cells was found at surgery. Invasive squamous carcinoma was found to arise in adjacent trachea. The thyroid gland was normal except for inflammatory changes. Aspiration biopsies of thyroid cysts may be misleading, especially when hemorrhagic; sclerosis should be performed with caution. 相似文献
78.
PURPOSE: We report the indications, complications, and outcomes of 104 corneal triple procedures in our institute. METHODS: Patient records of 104 consecutive cases of corneal triple procedure (penetrating keratoplasty with extracapsular cataract extraction and intraocular lens implantation) performed by experienced corneal surgeons between January 1992 and December 1997 were retrospectively reviewed. Relevant preoperative, operative, and postoperative data were collected. The outcome was assessed by the graft clarity and visual acuity at the last visit. Survival analysis of these grafts was determined by Kaplan-Meier method. RESULTS: Of 104 patients, 70 were men and 34 were women. Mean age of these patients was 48.5+/-17.1 years (range, 1-75 years). Corneal scarring with cataract was the reason for surgery in 69 (66.4%) cases. The intraoperative complications included vitreous upthrust in seven (6.9%) cases and posterior capsular dehiscence in three (2.9%) cases. The most common early postoperative complications were increased intraocular pressure in 19 (18.3%) and increased anterior chamber reaction in 25 (24%) cases. Posterior capsular opacification was seen in 26 (25%), graft reaction in 15 (14.4%), and secondary glaucoma in 15 (14.4%) cases. These formed the important late postoperative complications. The average postoperative follow-up was 23.7+/-17.6 months (range, 1.6-79.4 months); at which time 72% of the grafts remained clear. At last follow-up, 40% of patients had a visual acuity of > or = 20/40. CONCLUSIONS: Corneal scarring with cataract is the most common reason for triple procedure in this part of the world. This is a safe surgical procedure with good graft clarity and reasonable visual recovery. 相似文献
79.
PURPOSE: To report a case of conjunctival intraepithelial neoplasia presenting as corneal ulcer. METHOD: Case report of a 28-year-old man who presented with sudden onset of pain, redness, and watering in the right eye. Examination of right cornea revealed deep stromal infiltrate inferonasally. Adjacent to the infiltrate and straddling the inferonasal limbus, a reddish well-defined sessible lesion with prominent blood vessels was seen. After corneal scraping for microbiological evaluation, the patient was treated with frequent instillation of ciprofloxacin hydrochloride 0.3% eyedrops. RESULTS: Corneal scraping revealed no microorganisms. Infiltrate resolved promptly after excision of the lesion. Histopathologic evaluation of the excised lesion revealed conjunctival intraepithelial neoplasia. CONCLUSIONS: This case highlights the fact that conjunctival intraepithelial neoplasia at the limbus may present as corneal ulcer. This ulcer could have occurred secondary to a dellen formation and epithelial breakdown predisposing to a corneal ulcer. 相似文献
80.
Kumar A Sridhar MS Dada T Tewari HK Gupta SK 《Clinical & experimental ophthalmology》2000,28(1):38-40
Purpose : To study the efficacy of intravitreal pefloxacin in the management of suspected bacterial endophthalmitis. Methods : Twenty eyes with suspected postoperative bacterial endophthalmitis were given an intravitreal injection of pefloxacin (200 μg in 0.1 mL). If required the injection was repeated after 24 h. The main parameters evaluated were visual acuity, response to intravitreal therapy and any complications due to intravitreal pefloxacin. Results : Fourteen eyes (70%) responded to intravitreal pefloxacin therapy alone, while an additional pars plana vitrectomy was required in six eyes (30%). Nineteen eyes retained a visual acuity of 6/60 or better at 3 months after the initiation of therapy. A retinal detachment developed in one of the eyes which received intravitreal therapy. Conclusions : Intravitreal pefloxacin may be a useful alternative therapy in bacterial endophthalmitis. 相似文献