Search results for "cortical"
showing 10 items of 324 documents
Coded Excitation of the Fundamental Flexural Guided Wave in Coated Bone Phantoms
2017
There is an increasing interest of using ultrasonic guided waves to assess long cortical bones. In particular, a method of ultrasonic estimation of cortical thickness based on the fundamental flexural guided wave (FFGW), generally consistent with the A0 Lamb mode, has proven to be promising in vitro and modeling studies. Soft-tissue coating on top of the bone makes, however, the related in vivo application challenge. Visibility of FFGW on top of the soft tissue is not good due to the characteristic displacement profile of this mode, and due to its relatively high attenuation in the bone and surrounding tissue. Moreover, the soft tissue provides a direct propagation path for ultrasonic modes…
Studies of malformation syndromes of man XIB: the cerebro-hepato-renal syndrome of zellweger: Comparative pathology
1976
A study of 11 autopsied cases of the cerebro-hepato-renal syndrome of Zellweger (ZS) is reported. All cases had severe, persistent congenital hypotonia, hepatic lobular disarray, renal cortical cysts and pulmonary hypoplasia. Many had cardiovascular malformations, hepatomegaly, cerebral cortical gyral maldevelopment and pancreatic islet hyperplasia. Additional, less frequent findings are delineated. Results of iron content studies of hepatic and renal tissues are related to age of survival and possible development of fibrosis.
Endotheliotropic (hemolytic) nephroangiopathy and its various manifestation forms (thrombotic microangiopathy, primary malignant nephrosclerosis, hem…
1980
In hemolytic-uremic syndrome (HUS) various lesion types in the kidneys are observed in childhood. These are designated as the “glomerular type=G type” (essentially identical with thrombotic microangiopathy), as “arterial type=A type” (essentially identical with primary malignant nephrosclerosis (PMN)) or as “mixed type=G/A type”. With reference to characteristic cases, the most important morphological findings are described. In adults, in whom other diagnostic terms are used besides HUS, the same nephropathological types are observed. In the two phases of life, there occurs in addition renal cortical necrosis in subtotal nephroangiothrombosis. The G type and A type also have a different cli…
Cannabinoids, TRPV and nitric oxide: the three ring circus of neuronal excitability
2019
Endocannabinoid system is considered a relevant player in the regulation of neuronal excitability, since it contributes to maintaining the balance of the synaptic ionic milieu. Perturbations to bioelectric conductances have been implicated in the pathophysiological processes leading to hyperexcitability and epileptic seizures. Cannabinoid influence on neurosignalling is exerted on classic receptor-mediated mechanisms or on further molecular targets. Among these, transient receptor potential vanilloid (TRPV) are ionic channels modulated by cannabinoids that are involved in the transduction of a plethora of stimuli and trigger fundamental downstream pathways in the post-synaptic site. In this…
Increased cerebrospinal fluid albumin and immunoglobulin A fractions forecast cortical atrophy and longitudinal functional deterioration in relapsing…
2017
Background: Currently, no unequivocal predictors of disease evolution exist in patients with multiple sclerosis (MS). Cortical atrophy measurements are, however, closely associated with cumulative disability. Objective: Here, we aim to forecast longitudinal magnetic resonance imaging (MRI)-driven cortical atrophy and clinical disability from cerebrospinal fluid (CSF) markers. Methods: We analyzed CSF fractions of albumin and immunoglobulins (Ig) A, G, and M and their CSF to serum quotients. Results: Widespread atrophy was highly associated with increased baseline CSF concentrations and quotients of albumin and IgA. Patients with increased CSFIgA and CSFIgM showed higher functional disabilit…
Effect of platform switching on the peri-implant bone: A finite element study
2015
Background: There exists a relation between the presence and location of the micro-gap and the loss of peri-implant bone. Several authors have shown that the treatments based on the use of platform switching result in less peri-implant bone loss and an increased tissue stability. The purpose of this study was to analyse the effect of the platform switching on the distribution of stresses on the peri-implant bone using the finite element method. Material and Methods: A realistic 3D full-mandible finite element model representing cortical bone and trabecular bone was used to study the distribution of the stress on the bone induced by an implant of diameter 4.1 mm. Two abutments were modelled.…
Neurochemical correlates of brain atrophy in fibromyalgia syndrome: a magnetic resonance spectroscopy and cortical thickness study
2020
(1) Background: Recently, a series of clinical neuroimaging studies on fibromyalgia (FM) have shown a reduction in cortical volume and abnormally high glutamate (Glu) and glutamate + glutamine (Glx) levels in regions associated with pain modulation. However, it remains unclear whether the volumetric decreases and increased Glu levels in FM are related each other. We hypothesized that higher Glu levels are related to decreases in cortical thickness (CT) and volume in FM patients. (2) Methods: Twelve females with FM and 12 matched healthy controls participated in a session of combined 3.0 Tesla structural magnetic resonance imaging (MRI) and single-voxel MR spectroscopy focused on the thalami…
Influence of cortical bone and implant design in the primary stability of dental implants measured by two different devices of resonance frequency an…
2020
Background This study aimed to evaluate the effect of the implant design and the presence of cortical bone in the primary stability, as well as analyze the differences between the stability measurements obtained by two different resonance frequency analysis (RFA) devices. Material and methods A total of 80 Klockner implants of two different models [40 Essential Cone implants (group A) and 40 Vega implants (group B)] were used. The implants were placed in two polyurethane blocks that simulated the mechanical properties of the maxillary bone. One block featured a layer of cortical bone that was absent from the other block. The primary stability of all implants was measured by insertion torque…
Indikationen zur konventionellen Adrenalektomie
2008
INTRODUCTION: Conventional adrenalectomy still plays an important role, even in the era of minimally invasive endocrine surgery. It was the aim of our study to analyse the indications for conventional adrenalectomy in our own patients since the introduction of the minimally invasive technique in the year 1994 - laparoscopically and retroperitoneoscopically. PATIENTS AND METHODS: Between January 1994 and September 2006, a total of 412 adrenalectomies were performed in 380 patients. Out of these, 106 operations (25.7 %) were carried out conventionally in 98 patients, and 306 operations (74.3 %) endoscopically in 282 patients. RESULTS: Indications for conventional adrenalectomy were - as compa…