Search results for "regression"
showing 10 items of 2619 documents
Predicting First-Year College Student Retention: Validation of the College Persistence Questionnaire in a Spanish Sample
2019
This paper analyzes the factorial and predictive validity of a Spanish adaptation of the College Persistence Questionnaire (SCPQ) on the retention of first year students (FYS) at university. The participants were 490 FYS from two public universities in Southern Europe (Spain). Factorial analysis of the SCPQ (&chi
Biopartitioning micellar chromatography to predict skin permeability
2003
Dermal absorption of chemicals is an area of increasing interest to the pharmaceutical and cosmetic industries, as well as in dermal exposure and risk assessment processes. In this paper the capability of biopartitioning micellar chromatography (BMC) as an in vitro technique to describe compound percutaneous absorption is evaluated. A multivariate study (principal component analysis, partial least squares) is performed in order to evaluate the importance of some physicochemical variables on the skin permeability constant values. From these results, a quantitative retention-activity relationship model for predicting the skin permeability constants that uses the BMC retention data and melting…
A density functional study of flavonoid compounds with anti-HIV activity.
2005
Abstract Quantum chemical calculations at the DFT/B3LYP theory level, with the 6-31G* basis set, was employed to calculate a set of molecular properties of 26 flavonoid compounds with anti-HIV activity. The correlation between biological activity and structural properties was obtained by using the multiple linear regression method. The model obtained showed not only statistical significance but also predictive ability. We demonstrate in this paper that the anti-HIV activity of compounds can be related with the molecular hydrophobicity (ClogP), the electronegativity ( χ ) and the charges on some key atoms, while that the toxicity can be related with the electronic affinities (EA), ClogP and …
Modelo predictivo preliminar para la identificación de pacientes con oportunidades de mejora farmacoterapéutica
2010
Objective: To develop a prediction model for identifying patients with the possibility of improving pharmacotherapy during the process of pharmaceutical validation of the prescription. Method: Cross-sectional study over two months, performed in the Internal Medicine and Infectious Disease divisions. Detecting opportunities for improving quality of pharmaco¬therapy is done by means of a pharmacist's validation of the prescription. Based on the information we obtained through this process, we performed a multivariate logistic regression analysis using as prognostic factors the demographic, pharmacotherapy and clinical variables related to identifying any drug-related problems (DRPs) in the pa…
Predicción de riesgo de rechazo agudo en pacientes con trasplante renal
2009
Objective: Create a model to predict the risk of acute rejection of kidney transplant considering variables related to the immunosuppressant agent used, the receiver, the donor and the transplanted organ. Methods: Cohort study in a population of 68 patients with kidney transplants being treated with tacrolimus triple therapy. Predicting the risk of acute rejection was carried out with a logistic regression analysis using age, sex, re-transplant status, number of HLA incompatibilities, cold ischaemia time, acute tubular necrosis, induction with basiliximab or thymoglobulin and treatment type as explanatory variables. The contribution of variables associated with determining the blood concent…
Prediction of Aquatic Toxicity of Benzene Derivatives to Tetrahymena pyriformis According to OECD Principles
2016
Background: Many QSAR studies have been developed to predict acute toxicity over several biomarkers like Pimephales promelas, Daphnia magna and Tetrahymena pyriformis. Regardless of the progress made in this field there are still some gaps to be resolved such as the prediction of aquatic toxicity over the protozoan T. pyriformis still lack a QSAR study focused in accomplish the OECD principles. Methods: Atom-based quadratic indices are used to obtain quantitative structure-activity relationship (QSAR) models for the prediction of aquatic toxicity. Our models agree with the principles required by the OECD for QSAR models to regulatory purposes. The database employed consists of 392 substitut…
Correlation of pharmacological properties of a group of beta-blocker agents by molecular topology.
1995
Abstract The molecular connectivity method has been applied to the study of pharmacological properties, among which are found the angor treatment dose, α-distribution half-life and intravenous LD50 in mouse, of a group of β-blocker agents, verifying its application in the prediction of theoretic values for said pharmacological properties. To do this, the obtained multiple regression functions of the corresponding connectivity indices were used in relation with the experimental values of the properties, which are accompanied by the statistical parameters used in their selection criteria, as well as the corresponding random and cross-validation studies of said functions, which corroborate the…
The Prediction of Human Intestinal Absorption Based on the Molecular Structure
2014
Human Intestinal Absorption (HIA) has been modeled many times by using classification models. However, regression models are scarce. Here, Artificial Neural Networks (ANNs) are implemented for this purpose. A dataset of structurally diverse chemicals with their respective experimental HIA were used to design robust, true predictive and widespread applicable ANN models. An input variables pool was made up of structural invariants calculated by using either Dragon or our software Desmol 1. The selection of best variables was performed following three steps using the entire dataset of molecules. Firstly, variables poorly correlated with the experimental data were eliminated. Secondly, input va…
Knowledge of and attitudes to influenza in unvaccinated primary care physicians and nurses
2014
Primary healthcare workers, especially nurses, are exposed to the vast majority of patients with influenza and play an important role in vaccinating patients. Healthcare workers' misconceptions about influenza and influenza vaccination have been reported as possible factors associated with lack of vaccination. The objective of this study was to compare the characteristics of unvaccinated physicians and unvaccinated nurses in the 2011-2012 influenza season. We performed an anonymous web survey of Spanish primary healthcare workers in 2012. Information was collected on vaccination and knowledge of and attitudes to the influenza vaccine. Multivariate analysis was performed using unconditional …
Characterization of tachykinin receptors in the uterus of the oestrogen-primed rat
1998
The aim of our study was to characterize the tachykinin receptor population in the oestrogen-primed rat uterus. For this purpose, we investigated the receptor type(s) responsible for tachykinin-induced contraction of longitudinally-arranged smooth muscle layer. The effects of substance P (SP), neurokinin A (NKA), neurokinin B (NKB) and several of their analogues with well-defined selectivities for tachykinin NK1, NK2 and NK3 receptors were studied and their inhibition by the selective nonpeptide tachykinin receptor antagonists (S)1-(2-[3-(3,4-dichlorophenyl)-1-(3-isopropoxyphenylacetyl)piperidin-3-yl]ethyl)-4-phenyl-1-azoniabicyclo[2.2.2]octane chloride (SR 140333, NK1-selective), (S)-N-met…