a generalized heckman model is used for the joint modeling of longitudinal continuousresponses and dropout in order to see the influence of a small perturbation of the elements of thecovariance structure on displacement of the likelihood. the perturbation from random dropout in thedirection of informative dropout is considered for mastitis data.

Introduction:In this study, a non-invasive method based on consecutive ultrasonic image processing is introduced to assess time rate changes of the carotid artery wall displacement, velocity and acceleration in the longitudinal direction. The application of these parameters to discriminate healthy and atherosclerotic arteries was evaluated. Methods:Longitudinal displacement rate of common ...

background hepatitis b virus (hbv) is one of the most common chronic viral infections in the world. iran has a low to intermediate hbv prevalence and approximately 1.5 million people are living with hbv infection. the impact of hbv in iran is unknown and given the very low levels of alcohol consumption, this region provides an opportunity to examine the impact of isolated chronic hbv infection....

background: the bipolar disorder patients follow-up (bdpf) project is a longitudinal, prospective and naturalistic study. the purpose of the present report is to introduce the project, elaborate its methods, and present the reliability data of the utilized symptoms rating scales. methods: the sampling started in may 2008 and is still in progress. the probands are assessed at the beginning of th...

Ossification of the posterior longitudinal ligament (OPLL) and ossification of the ligamentum flavum (OLF) have been recognized as causes of myelopathy due to thickening of the ligaments resulting in narrowing of the spinal canal and compression of the spinal cord. However, few studies have focused on predicting stress distribution under conditions of OPLL and OLF based on clinical aspects such...

Patients with cervical ossification of the posterior longitudinal ligament (OPLL) who are K-line (-) are thought to have poor clinical outcomes after laminoplasty. The aim of this study is to compare the clinical results of patients with OPLL who were K-line (-) in the neck neutral position but K-line (+) in the neck extension position (NEP group) with patients with OPLL who were K-line (+) in ...

Iatrogenic spinal cord herniation is a rare complication following spinal surgery. We introduce a posterior trans-dural repair technique used in a case of thoracic spinal cord herniation through a ventral dural defect following resection of ossification of the posterior longitudinal ligament (OPLL) in the cervicothoracic spine. A 51-year-old female was suffering from paraplegia after laminectom...

Objective Our purpose here was to identify risk factors of poor outcome after anterior operation in patients with cervical ossification of the posterior longitudinal ligament (OPLL). Methods This study retrospectively reviewed 98 patients who underwent anterior surgery for improving neurological symptoms. The Japanese Orthopedic Association (JOA) recovery rate <50% was defined as poor surgica...

AIM We analyzed the demographics, clinical and radiological characteristics of non-myelopathic cervical ossification of the posterior longitudinal ligament (OPLL) patients. MATERIAL AND METHODS This study included 115 patients with cervical OPLL but without myelopathy. Demographic features of age, sex, and the nature of the patient"s symptoms were evaluated. Clinically, visual analog scale (V...

Ossification of the posterior longitudinal ligament of the spine (OPLL) is a common disease in aging populations and sometimes results in serious neurological problems due to compression of the spinal cord and nerve roots. OPLL is a multi-factorial (polygenic) disease controlled by genetic and environmental factors. Studies searching for the genetic component of OPLL, using linkage and associat...