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41.
The diagnostic utility of static immittance (SI) with respect to distinguishing healthy from otosclerotic ears was investigated at different probe-tone frequencies in 68 healthy ears and 36 ears with surgically confirmed otosclerosis. Because one effect of otosclerosis is to shift the resonant frequency of the middle ear to higher values as a result of increased stiffness of the middle ear system, it was hypothesized that SI measured at higher probe-tone frequencies may provide a better distinction between healthy and otosclerotic ears. As expected, the results of this study indicate that SI measured at higher probe-tone frequencies is superior to a standard low probe tone in the detection of otosclerotic ears. Through systematic and objective comparisons of relevant probetone frequencies using both group statistics and test performance analysis, the present study suggests 630 Hz as an optimum probe-tone frequency for measuring SI with respect to distinguishing healthy ears from otosclerotic ears. 相似文献
42.
43.
Losartan reduces the costs associated with diabetic end-stage renal disease: the RENAAL study economic evaluation 总被引:2,自引:0,他引:2
Herman WH Shahinfar S Carides GW Dasbach EJ Gerth WC Alexander CM Cook JR Keane WF Brenner BM 《Diabetes care》2003,26(3):683-687
OBJECTIVE: To evaluate the within-trial effect of losartan and conventional antihypertensive therapy (CT) compared with placebo and CT on the economic cost associated with end-stage renal disease (ESRD). RESEARCH DESIGN AND METHODS: The Reduction of End Points in Type 2 Diabetes With the Angiotensin II Antagonist Losartan (RENAAL) study was a multinational double-blind randomized placebo-controlled clinical trial designed to evaluate the renal protective effects of losartan on a background of CT (excluding ACE inhibitors and angiotensin II receptor agonists [AIIAs]) in patients with type 2 diabetes and nephropathy. The primary composite end point was doubling of serum creatinine, ESRD, or death. Data on the duration of ESRD were used to estimate the economic benefits of slowing the progression of nephropathy. The cost associated with ESRD was estimated by combining the days each patient experienced ESRD with the cost of ESRD over time. The cost of ESRD for individuals with diabetes was estimated using data from the U.S. Renal Data System. Total cost was estimated as the sum of the cost associated with ESRD and the cost of study therapy. RESULTS-We estimated that losartan and CT compared with placebo and CT reduced the number of days with ESRD by 33.6 per patient over 3.5 years (P = 0.004, 95% CI 10.9-56.3). This reduction in ESRD days resulted in a decrease in cost associated with ESRD of 5144 US dollars per patient (P = 0.003, 95% CI 1701 to 8587 US dollars). After accounting for the cost of losartan, the reduction in ESRD days resulted in a net savings of 3522 US dollars per patient over 3.5 years (P = 0.041, 143 to 6900 US dollars). CONCLUSIONS: Treatment with losartan in patients with type 2 diabetes and nephropathy not only reduced the incidence of ESRD, but also resulted in substantial cost savings. 相似文献
44.
Pattern Recognition in Pulmonary Tuberculosis Defined by High Content Peptide Microarray Chip Analysis Representing 61 Proteins from M. tuberculosis
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45.
Zahra Babazadeh Shahnaz Razavi Marziyeh Tavalaee Mohammad Reza Deemeh Maryam Shahidi Mohammad Hossein Nasr-Esfahani 《Reproductive toxicology (Elmsford, N.Y.)》2010,29(1):120-124
DNA fragmentation in human sperm has been related to endogenous and exogenous factors. Exogenous factors can also affect leukocyte DNA integrity. This study evaluated the relation between sperm DNA damage and leukocyte DNA integrity, as a predictor of exogenous factors. DNA damage in the sperm and leukocytes of 41 individuals undergoing ICSI were measured by Comet assay. In addition, sperm chromatin dispersion (SCD) was carried out on semen samples. A positive correlation was observed between the DNA integrity of sperm with leukocytes. When patients were divided into low and high DNA exposure groups, sperm DNA fragmentation was significantly different between the two groups. Cleavage rate and embryo quality showed significant correlation with leukocyte DNA integrity. The results showed that leukocyte DNA integrity could be used to identify individuals at high risk in order to reduce the extent of DNA damage in patients before ICSI in order to improve the subsequent outcome of this procedure. 相似文献
46.
47.
Wayne Hoss Jeanette M. Woodruff Brenda R. Ellerbrock Sumudra Periyasamy Shahnaz Ghodsi-Hovsepian Jennifer Stibbe Mark Bohnett William S. Messer Jr. 《Brain research》1990,533(2):232-238
Pilocarpine was tested biochemically in vitro for its ability to stimulate phosphoinositide (PI) turnover in the hippocampus (M1/M3 responses) where it displayed 35% of the maximal carbachol response with an EC50 value of 18 microM, and low-Km GTPase in the cortex (M2 response), where it had 50% of the maximal carbachol response with an EC50 value of 4.5 microM. Behaviorally, pilocarpine was able to restore deficits in a representational memory task (sensitive to M1 antagonists) produced by intrahippocampal injections of AF64A. Twenty-three low-energy conformations of protonated pilocarpine were generated using the program MacroModel. The data indicate that pilocarpine is a partial agonist at both M1 and M2 muscarinic receptors in the CNS. Behaviorally, with respect to the memory task, M1 effects of pilocarpine apparently predominate. It also is conceivable that different conformations of pilocarpine are active as agonists at different muscarinic receptor subtypes. 相似文献
48.
Mahdieh Khodaei Camila Pachêco-Pereira Suzana Trac Andrew Chan Lawrence H Le Edmond Lou 《The spine journal》2018,18(11):2128-2139
BACKGROUND CONTEXT
Adolescent idiopathic scoliosis (AIS) is a three-dimensional deformity recognized with lateral curvature of the spine as well as axial vertebral rotation. Surgical interventions are recommended when patients with AIS have severe curvature (Cobb angle >45o). Spinal flexibility is one of important parameters for surgeons to plan surgical treatment. Few radiographic methods have been developed to assess spinal flexibility.PURPOSE
A systematic review was performed to evaluate which preoperative radiographic methods should be used to estimate spinal flexibility based on the postoperative outcomes.STUDY DESIGN
Studies which included any of the five radiographic methods: (1) supine side-bending (SBR), (2) fulcrum-bending (FBR), (3) traction, (4) push-prone, and (5) suspension were reviewed and compared to determine which method provided the most accurate estimation of the postoperative outcomes.PATIENT SAMPLE
Seven case series, one case control, and multiple cohort studies reported the flexibility assessment methods with the estimations of postoperative outcomes on patients with AIS.OUTCOME MEASURES
The flexibility index defined as a correction rate relative to flexibility rate was used to estimate the immediate and final follow-up postoperative outcomes.METHODS
Seven databases searched included MEDLINE, CENTRAL, EMBASE, CINAHL, Web of Science, LILACS, and Google Scholar. Three independent reviewers were involved for abstracts and full-texts screening as well as data extraction. The Quality in Prognostic Studies quality appraisal tool was used to assess the risk of bias within the studies. Also, the GRADE system rate was used to assess the evidence level across the studies.RESULTS
Forty-six articles were included. The distribution of the five flexibility methods in these 46 studies were SBR 38/46 (83%), fulcrum bending radiograph (FBR) 16/46 (35%), traction radiograph 5/46 (11%), push-prone 1/46 (2%), and suspension 1/46 (2%). Based on the overall assessment of flexibility indices, FBR had the best estimation of postoperative correction among the five methods. FBR method provided the best estimations of immediate and final follow-up postoperative outcomes for moderate (25°–45°) and severe (>45°) curves, respectively. For main thoracic and thoracolumbar/lumbar curves, the best estimations were traction, and FBR. However, in the reviewed articles, the risk of bias was rated moderate and the quality of evidence was rated very low to low so that a strong conclusive statement cannot be made.CONCLUSIONS
SBR method was the most commonly used method to assess the spinal flexibility. The FBR method was the most accurate method to estimate the postoperative outcomes based on the limited evidence of the 46 articles. 相似文献49.
Iqbal J Shahnaz G Perera G Hintzen F Sarti F Bernkop-Schnürch A 《European journal of pharmaceutics and biopharmaceutics》2012,80(1):95-102
The aim of the present study was to develop an oral delivery system for the peptide drug leuprolide. Gel formulations based on unmodified chitosan/reduced glutathione (GSH) and chitosan-thioglycolic acid (chitosan-TGA)/GSH were prepared, and their effect on the absorption of leuprolide was evaluated in vitro and in vivo in male Sprague Dawley rats. Transport studies were performed with freshly excised rat intestinal mucosa mounted in Ussing-type chambers. Due to the addition of gel formulations comprising 0.5% (m/v) unmodified chitosan/0.5% (m/v) GSH and 0.5% (m/v) chitosan-TGA/0.5% (m/v) GSH, the transport of leuprolide across excised mucosa was improved up to 2.06-fold and 3.79-fold, respectively, in comparison with leuprolide applied in buffer (Papp = 2.87 ± 0.77 × 10−6 cm/s).In vivo, the addition of oral gel formulation comprising 8 mg of unmodified chitosan, 1 mg of GSH and 1 mg of leuprolide increased the area under the plasma concentration-time curve (AUC0-8) of leuprolide 1.39-fold in comparison with leuprolide having been administered just in saline. Moreover, the administration of oral gel formulation comprising 8 mg of chitosan-TGA, 1 mg of GSH and 1 mg of leuprolide resulted in a further enhanced leuprolide plasma concentration, and the area under the plasma concentration-time curve (AUC0-8) of leuprolide was increased 3.72-fold in comparison with the control. With the oral gel formulation comprising 8 mg of chitosan-TGA, a relative bioavailability (versus s.c. injection) of 4.5% was achieved in contrast to the control displaying a relative bioavailability of 1.2%. Thus, according to the achieved results, it is suggested that chitosan-TGA in combination with GSH is a valuable tool for improving the oral bioavailability of the peptide drug leuprolide. 相似文献
50.
Bruce E. Hayward Michel De Vos Nargese Talati M. Reza Abdollahi Graham R. Taylor Esther Meyer Denise Williams Eamonn R. Maher Faridon Setna Kausar Nazir Shahnaz Hussaini Hussain Jafri Yasmin Rashid Eamonn Sheridan David T. Bonthron 《Human mutation》2009,30(5):E629-E639
Familial biparental hydatidiform mole (FBHM) is a maternal‐effect autosomal recessive disorder in which recurrent pregnancy failure with molar degeneration occurs. The phenotype mimics molar pregnancy due to androgenesis, despite the normal genetic makeup of the conceptus. FBHM appears to result from a failure to establish correct maternal epigenetic identity at imprinted loci during oogenesis. Several women affected with FBHM have previously been shown to have biallelic mutations in the NLRP7 gene (NALP7). Here, we present the results of epigenetic and mutational analysis on FBHM patients from 11 families, 10 of them novel. We demonstrate a methylation defect at imprinted loci in tissue from four new FBHM cases. Biallelic NLRP7 mutations, including eight previously undescribed mutations, were found in all but one family. These results indicate for the first time that maternal imprints at some loci may be correctly specified in FBHM conceptions, since differential methylation of SGCE/PEG10 was preserved in all four cases. © 2009 Wiley‐Liss, Inc. 相似文献