Modular acetabular systems have several advantages; however, increased polyethylene wear has been recognized as a disadvantage. In our study, an acetabular shell design with a highly polished inner surface, a locking mechanism that minimizes micromotion, and a high polyethylene liner to shell conformity was evaluated. A prospective cohort of 50 consecutive hips was followed up for a mean of 3.
View Article and Find Full Text PDFStudies of cumulative HIV incidence suggest that cofactors such as genital ulcer disease, HIV disease stage, and male circumcision influence HIV transmission; however, the heterosexual infectivity of HIV-1 is commonly cited as a fixed value (approximately 0.001, or one transmission per 1000 contacts). We sought to estimate transmission cofactor effects on the heterosexual infectivity of HIV-1 and to quantify the extent to which study methods have affected infectivity estimates.
View Article and Find Full Text PDFtAnGo is a large randomised trial assessing the addition of gemcitabine(G) to paclitaxel(T), following epirubicin(E) and cyclophosphamide(C) in women with invasive higher risk early breast cancer. To assess the safety and tolerability of adding G, a detailed safety substudy was undertaken. A total of 135 patients had cardiac, pulmonary and hepatic function assessed at (i) randomisation, (ii) mid-chemotherapy, (iii) immediately post-chemotherapy and (iv) 6 months post-chemotherapy.
View Article and Find Full Text PDFObjectives: To assess and summarize the published literature on the extent to which bacterial vaginosis may increase the risk of HIV acquisition.
Design: Meta-analysis of published studies.
Methods: Medline and other electronic databases were systematically searched for eligible publications.
Use of well persons as the comparison group for laboratory-confirmed cases of sporadic salmonellosis may introduce ascertainment bias into case-control studies. Data from the 1996-1997 FoodNet case-control study of laboratory-confirmed Salmonella serogroups B and D infection were used to estimate the effect of specific behaviours and foods on infection with Salmonella serotype Enteritidis (SE). Persons with laboratory-confirmed Salmonella of other serotypes acted as the comparison group.
View Article and Find Full Text PDFAppl Biochem Biotechnol
January 2009
The bacterial leaching of zinc and iron from solid wastes at the Isdemir iron and steel plant has been investigated using Acidithiobacillus ferrooxidans as the bacterial agent. The effects of a range of operational parameters, including particle size, solids concentration and pH, on the efficiency of the bioleaching process were investigated. In each test, several variables were determined to assess the efficiency of leaching, including slurry pH and redox potential, temperature, bacteria population and concentrations of zinc and iron in solution.
View Article and Find Full Text PDFAn iteration procedure is used to optimize the solute descriptors for 94 compounds suitable for characterizing the retention properties of open-tubular columns for gas chromatography in the intermediate temperature range of 160-240 degrees C. These solute descriptors are used to calculate the system constants of the solvation parameter model for nine open-tubular columns (SPB-Octyl, HP-5, Rtx-440, Rxi-50, Rtx-OPP, DB-1701, DB-225, HP-Innowax, and HP-88) at increments of 20 degrees C from 160 to 240 degrees C. The optimized descriptors afford a two- to three-fold improvement in the fit to the retention model compared with literature values as determined by the standard deviation of the difference between the model predicted and experimental retention factors (log k).
View Article and Find Full Text PDFDetection of persistent cervical carcinogenic human papillomavirus (HPV) DNA is used as a marker for cervical cancer risk in clinical trials. The authors performed a systematic review and meta-analysis of the association between persistent HPV DNA and high-grade cervical intraepithelial neoplasia (CIN2-3), high-grade squamous intraepithelial lesions (HSIL), and invasive cervical cancer (together designated CIN2-3/HSIL+) to evaluate the robustness of HPV persistence for clinical use. MEDLINE and Current Contents were searched through January 30, 2006.
View Article and Find Full Text PDFIn this work multiple linear regression (MLR) and artificial neural network (ANN) were used to predict the gradient retention times of diverse sets of organic compounds in four separate data sets. Descriptors which were used as inputs of these models are five linear free energy relationship (LFER) solute parameters including E, S, A, B and V. In the first step eight separate multiple linear regression and artificial neural network models were used to predict the gradient retention time for each gradient condition separately.
View Article and Find Full Text PDFA patient with a diagnosis of hand-arm vibration syndrome was referred for a second opinion. He worked as a multi-skilled operative in the housing department of a local authority, a job not normally associated with high levels of exposure to hand-transmitted vibration ( > 2.5 m/s(2) A(8)).
View Article and Find Full Text PDFCancer Causes Control
October 2008
Body size relatively early in life may influence men's later rate of prostate cancer. We searched for published, English-language studies of the association between prostate cancer incidence or mortality and body size between ages 5 and 29 years. We summarized analyses of childhood body size, early-adult waist circumference, and early-adult body mass index (BMI).
View Article and Find Full Text PDFOsteoarthritis (OA) is a common joint disease characterized by articular cartilage degeneration. The etiology of OA is unknown. Because several previous studies have shown that primary cilia play critical roles in joint development, this study examined the incidence and morphology of primary cilia in chondrocytes during joint degeneration in a naturally occurring bovine model of OA.
View Article and Find Full Text PDFThe solvation parameter model is used to characterize the retention properties of a poly(methylphenylsiloxane) column Rxi-50 over the temperature range 60-240 degrees C. The smooth variation of the system constants with temperature affords a general picture of how the relative importance of the different intermolecular interactions change with temperature. The system constants and retention factors for varied compounds are compared with those for Rtx-50 prepared with a similar stationary phase but using a different surface deactivation technique.
View Article and Find Full Text PDFA database of system constants for 32 open-tubular columns at 100 degrees C is used to identify stationary phases for obtaining a wide selectivity space in comprehensive GC. Three parameters based on the Euclidean distance (D-parameter) or vectors (d-parameter and costheta) in hyperspace are used to establish the chemical similarity and retention correlation as an inverse scale of selectivity differences. It is shown that the poly(methyloctylsiloxane) stationary phase is the best candidate for a low-selectivity stationary phase and affords a wider selectivity space when combined with a selective polar stationary phase than poly(dimethylsiloxanes).
View Article and Find Full Text PDFQuantitative structure-retention relationships (QSRRs) attempt to quantitatively understand the relationship between structure and retention and quantitative structure-property relationships (QSPRs) to explore the prediction of molecular properties from retention in chromatography. The application of these techniques to micellar electrokinetic chromatography (MEKC) and microemulsion electrokinetic chromatography (MEEKC) using surfactants, vesicles and liposomes is reviewed. A database of system constants for the solvation parameter model is assembled and critically discussed with respect to the interpretation of solvation properties of micellar pseudophases and their use to identify correlation models for the estimation of physicochemical and environmental properties from retention in MEKC and MEEKC.
View Article and Find Full Text PDFMuch medical research is observational. The reporting of observational studies is often of insufficient quality. Poor reporting hampers the assessment of the strengths and weaknesses of a study and the generalizability of its results.
View Article and Find Full Text PDFThe STROBE guidelines (for Strengthening the Reporting of OBservational Studies in Epidemiology) add to a lengthy catalog of attempts to keep epidemiologists on more or less straight and more or less narrow paths charted by guideline authors. STROBE has an ambitious goal, and may prove highly useful for some. It raises concern, however, about a problem generic to guidelines, namely how long they will be useful.
View Article and Find Full Text PDFTwo methods are presented for deforming giant unilamellar vesicles with holographic optical tweezers. The first allows ultrahigh spatial- and temporal-resolution optical tracking of membrane deformations, by using embedded silica microspheres in a giant unilamellar vesicle as tracers. The vesicles are stretched by moving several beads with multiple optical tweezers and then are released from an elongated shape.
View Article and Find Full Text PDFThe proportion of infant pertussis cases due to transmission from casual contact in the community has not been estimated since before the introduction of pertussis vaccines in the 1950s. This study aimed to estimate the proportion of pertussis transmission due to casual contact using demographic and clinical data from a study of 95 infant pertussis cases and their close contacts enrolled at 14 hospitals in France, Germany, Canada, and the U.S.
View Article and Find Full Text PDFMuch medical research is observational. The reporting of observational studies is often of insufficient quality. Poor reporting hampers the assessment of the strengths and weaknesses of a study and the generalisability of its results.
View Article and Find Full Text PDFMuch medical research is observational. The reporting of observational studies is often of insufficient quality. Poor reporting hampers the assessment of the strengths and weaknesses of a study and the generalizability of its results.
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