Search results for "Medulla"
showing 10 items of 164 documents
Distribution of dopamine-beta-hydroxylase—like immunoreactivity in the rat pineal organ
1985
The aim of the present investigation was to study the distribution in the rat pineal gland of dopamine-beta-hydroxylase (DBH) which is essential for the formation of the melatonin synthesis-regulating substance noradrenaline (NA). In 5- and 8-month-old male Sprague-Dawley rats DBH-like immunoreactivity (DBH-LI) was studied using polyclonal antibodies against DBH and the indirect immunofluorescent technique. DBH-LI was mainly located in pineal nerve fibres coming from the superior cervical ganglia. The intensity of the staining reaction was considerably lower than in non-pineal noradrenergic nerve fibres and the impression was gained by comparison of DBH-LI specimens with glyoxylic acid-trea…
Thickness sensitivity of ultrasound velocity in long bone phantoms
2004
One approach to bone disease diagnosis such as osteoporosis is to measure the velocity of ultrasound propagating axially along long bones. In this study, the variation in velocity as a function of radial position was assessed using two polyvinyl chloride (PVC) bone phantoms with cross-sectional geometry similar to the human tibia but differing in medullary cavity diameter. Two ultrasonometers were used: these were a commercial device operating at a relatively high frequency (HF) of 1.25 MHz and a prototype low frequency (LF) device operating at approximately 200 kHz. The LF measurements showed a larger variation with radial position, with changes in velocity of up to 20% occurring around th…
Nachweis von Markembolien wÄhrend Oberschenkelmarknagelungen mittels transösophagealer Echokardiographie
1989
Kardiopulmonale Komplikationen nach Marknagelosteosynthesen, insbesondere am Oberschenkel, sind bekannt. WAhrend der Nagelung einer Oberschenkelquerfraktur mit einem, geschlossenen distalen Fragment konnten durch transsophageale Echokardiographie im rechten Herzen durchstromende echogene Partikel nachgewiesen werden. Das intrakardiale Auftreten dieser Partikel stand in engem zeitlichen Zusammenhang mit dem Aufbohren der femoralen Markhohle und kann als Nachweis verschleppter Marksubstanz gedeutet werden. Die intraoperative Echokardiographie bietet sich an, Untersuchungen uber die Pathophysiologie kardiopulmonaler VerAnderungen nach Marknagel osteosynthesen durchzufuhren und die EffektivitAt…
Protective effect of menhaden oil on renal necrosis occurring in weanling rats fed a methyl-deficient diet
2002
Weanling rats fed a lipotropic-deficient diet (LDD) may develop acute renal failure with morphological features that vary from focal tubular necrosis to widespread cortical necrosis and eventually reparative changes. The type of lipid in the diet influences the development of renal necrosis. The aim of this work was to study the effect of dietary menhaden oil on the development of acute renal failure induced in weanling rats fed a methyl-deficient diet. Experiment I: 40 weanling Sprague-Dawley male rats were allotted to 4 different groups and fed as follows: group 1, LDD with hydrogenated vegetable oil and corn oil as lipids; group 2, LDD with menhaden oil as lipid; group 3 and 4, similar t…
Landmarks for vertebral artery repositioning in bulbar compression syndrome: anatomic and microsurgical nuances
2004
Abstract OBJECTIVE: The purpose of this study was to better elucidate the anatomic relationship between the vertebral artery (VA) along with its perforating vessels and the brainstem to develop anatomic guidelines that would be helpful when decompressing medulla oblongata compressed by the VA. METHODS: Microanatomy dissection was performed in six formalin-fixed cadaveric heads. The VA, posteroinferior cerebellar artery (PICA), anteroinferior cerebellar artery (AICA), and lower brainstem perforators were examined under magnification using a surgical microscope. The outer diameters of the VA, PICA, and AICA were measured. The distance between the VA, lying within the lateral cerebellomedullar…
Early Auditory Evoked Potentials (EAEP) in Neurosurgery — A New Method for Diagnosis and Localization of Posterior Fossa Tumors in Childhood
1983
Auditory stimuli of suprathreshold intensity (above 60 dBHL) evoke about 15 waves: an early series (EAEP) during the initial 10 milliseconds (ms), a middle latency sequence (8 to 50 ms) and the longer latency cortical potentials (50 – 300 ms). PICTON et al. (1974) made a survey of all three potential groups. Only the EAEP (waves I to IV) are generated in the infratentorial part of the brain and reflect progressive activation of the auditory tracts and nuclei (Fig. 1): Wave I is assumed to originate at the distal part of the acoustic nerve, wave II in the medulla, wave III in the caudal and wave IV in the rostral pons and wave V in the midbrain (STARR and ACHOR, 1975; STOCKARD and ROSSITER, …
Spatial distribution of various types of bulbar respiratory neurons in the rabbit
1977
In anesthetized rabbits, the burst activity of 277 single respiratory neurons was recorded extracellularly. The neurons were classified according to their spike incidence distribution within the respiratory cycle and to their response to lung distension or collapse (alpha or beta type). About one third of the neurons found in all animals were located at the level of the caudal end of the promontorium gliosum, widely scattered over the bulbar cross-section. More rostrally the units were located within a dorsal area neighbouring the tractus solitarius, more caudally within a ventral field surrounding the nucleus ambiguus. Most of the inspiratory neurons (the most frequently encountered type) …
Pathogenesis of circulatory reactions triggered by nervous reflexes during the implantation of bone cements.
1983
Circulatory and respiratory reactions during the implantation of joint endoprostheses have been observed for years. The components of the bone cements used for anchoring (methyl methacrylate monomer) or the outpour of bone marrow substances from the affected bone marrow cavity are thought to be chiefly responsible for these effects. However, our previous investigations demonstrated unambiguously that reactions of this type can be attributed to direct nervous-reflex mechanisms triggered by the pressure rise in the medullary canal, and that, in addition, bone marrow embolism plays a part in serious circulatory incidents. The investigations on which the present paper is based have confirmed th…
“Weekly docetaxel and gemcitabine as first line treatment for metastatic breast cancer: results of a multicenter phase II study”
2004
<i>Objectives:</i> We conducted a multicenter phase II study to evaluate the clinical efficacy, toxicity, and dose intensity of a new weekly schedule of docetaxel and gemcitabine as first-line treatment of metastatic breast cancer patients. <i>Methods:</i> We enrolled 58 patients, 52% of whom had received a previous anthracycline-containing chemotherapy. The treatment schedule was: docetaxel 35 mg/m<sup>2</sup> and gemcitabine 800 mg/m<sup>2</sup> i.v. on days 1, 8, 15 every 28 days. <i>Results:</i> All patients were assessable for toxicity and 56 for efficacy. Overall response rate was 64.3% with 16.1% of complete responses and 48…
Dynamische Analyse von Osteosynthesen am Olecranon: ein in-vitro Vergleich zweier Osteosynthesesysteme / Dynamic analysis of olecranon osteosyntheses…
2008
INTRODUCTION The aim of the present study was to develop a test setup with continuous angle alteration to imitate elbow joint motion for the mechanical evaluation of tension band wiring and a newly designed intramedullary nail. MATERIALS AND METHODS The servo-pneumatical test stand worked with a rotational angle-adjusted and a linear force-adjusted engine. The fracture model was dynamically tested under cyclic loading imitating elbow joint motion. In total, 14 fresh cadaver upper extremities underwent olecranon fracture by means of transverse osteotomy and were assigned to two groups: tension band wiring and intramedullary nailing. There was a continuous angle alteration between 0 and 1000 …