Search results for "structures"
showing 10 items of 4815 documents
Color discrimination under mesopic conditions in cats and humans
1995
The ability to discriminate colors under various levels of mesopic illumination was studied in three cats using colored papers as stimuli and with a computer controlled training schedule. Discrimination based on brightness differences was prevented using a new method in which illuminant color was varied. The luminance threshold for color discrimination in cats was found to be 0.5 cd/m2, close to the cone threshold reported by others from ganglion cell recordings. The same experiment was carried out with human subjects and revealed a luminance threshold of 0.00042 cd/m2 for color discrimination.
Human endometrial CD98 is essential for blastocyst adhesion.
2010
Background Understanding the molecular basis of embryonic implantation is of great clinical and biological relevance. Little is currently known about the adhesion receptors that determine endometrial receptivity for embryonic implantation in humans. Methods and Principal Findings Using two human endometrial cell lines characterized by low and high receptivity, we identified the membrane receptor CD98 as a novel molecule selectively and significantly associated with the receptive phenotype. In human endometrial samples, CD98 was the only molecule studied whose expression was restricted to the implantation window in human endometrial tissue. CD98 expression was restricted to the apical surfac…
How Can We Assess the Perception of Induced Dyspnea in Chronic Obstructive Pulmonary Disease?
2004
Objective TO evaluate various methods for studying the perception of dyspnea in chronic obstructive pulmonary disease (COPD) using a new parameter, the change in Borg scale rating, and others already in use: the linear regression slope and the application of Stevens' law to the response-perception curve-ie change in forced expiratory volume in 1 second (ΔFEV 1 )-change in dyspnea (Adyspnea). Patients and method A bronchial challenge test was performed on 70 patients with stable COPD and no contraindications for performing the test (European Respiratory Society criteria), during which dyspnea was measured (Borg scale) after each nebulization. Perception was analyzed using: a ) the linear reg…
Complications Through the Use of Viscoelastics
2000
Viscoelastic material retained behind the IOL may cause a capsular bag distension in the early postoperative period. These eyes accumulate a transparent substance in the closed chamber inside the capsular bag from the IOL blocking the capsular opening. The capsular bag distension was first discribed by Davison in 1990. Miyake et al. proposed a new classification of capsular block syndrome and supposed viscoelastic material to cause early-postoperative capsular block syndrome (Miyake et al., 1999). Capsular bag distension after optic capture of a sulcus-fixated IOL was described by Basti et al. (1999).
Activities of angiotensin-converting enzymes ACE1 and ACE2 and inhibition by bioactive peptides in porcine ocular tissues.
2009
An active local renin-angiotensin system (RAS) has recently been found in the human eye. The aim of the present study was to compare the activities of central RAS enzymes (ACE1 and 2) in porcine ocular tissues, morphologically and physiologically close to the human eye. In addition, the effects of three ACE-inhibitory tripeptides on these enzymes were evaluated.Enucleated fresh porcine eyes were used. Activities of ACE1 and ACE2 and their inhibition by bioactive tripeptides (Ile-Pro-Pro, Val-Pro-Pro, Leu-Pro-Pro) as well as by a standard ACE-inhibitor captopril were assayed in the vitreous body, the retina and the ciliary body using fluorometric detection methods.Activity of ACE1 as well as…
Computerized analysis of normal fetal heart rate pattern throughout gestation.
2009
Objective To analyze the evolution of computerized cardiotocography (cCTG) parameters throughout gestation in a large archive of traces from healthy fetuses. Methods This was a cross-sectional study of the first cCTG record from 4412 singleton fetuses with good pregnancy outcome. Normal ranges of cCTG parameters for 25 to 42 weeks were derived from analysis of only one cCTG record per fetus, and the relationship between the parameters and gestational age was investigated. Results Fetal heart rate (FHR) accelerations, short- and long-term variation overall, duration of episodes of high and low variation and variation in high episodes increased with advancing gestation. In contrast, maternal …
Color Doppler imaging of the eye and orbit A synopsis of a 400 case experience
2009
Color Doppler imaging (CDI) is a recent advance in ultrasonography that allows simultaneous two-dimensional imaging of structure and blood flow. Doppler information is superimposed in color over a conventional gray-scale ultrasound image. Using this technique we have examined 400 eyes. The central retinal artery, posterior ciliary arteries, ophthalmic artery, the central retinal vein and the vortex veins could be located in all normal eyes. Using the color image as a guide, Doppler spectral analysis is used for quantitative assessment of blood flow velocity in these vessels. We also studied patients with intraocular tumors, arterial and venous retinal occlusions, orbital vascular anomalies …
Radiäre Optikusneurotomie (RON) bei retinalen Zentralvenenverschlüssen
2007
Background Compression in the lamina cribrosa is discussed as a reason for central retinal vein occlusion. Radial optic neurotomy should release the pressure and increase venous blood outflow. Patients and methods In a clinical trial 27 eyes with central retinal vein occlusion (22 eyes with clinical ischaemia, 5 eyes with continuous disc oedema and visual acuity below 4/10) underwent surgical decompression by vitrectomy and radial optic neurotomy. During surgery the intravenous pressure in the central vein was tested by infusion dynamometry before and right next to the incision. Follow up-time minimally was 1.5 years. Results Infusion dynamometry demonstrated a decrease of the central vein …
Blood flow velocity waveforms of the middle cerebral artery and abnormal neurological evaluations in live-born fetuses with absent or reverse end-dia…
1992
Abstract We studied 37 fetuses with absent or reverse end-diastolic flow velocities (AREDFV) of the umbilical arteries with respect to the mode of delivery, fetal acidosis, resistance index of the middle cerebral arteries, and abnormal neurological evaluation at the time of discharge from the department of pediatrics. A control group with normal umbilical artery flow velocity waveforms was matched for gestational age. Fetuses with AREDFV were delivered almost exclusively by cesarean section, in most cases due to fetal distress. Metabolic changes with decreased base excess values were found more often in fetuses with AREDFV, but no difference could be detected with respect to severe fetal ac…
Toxisches Schock Syndrom
1990
We report about a one year old girl with toxic shock syndrome (TSS), which was confirmed by a significant rise of TSST-1 titers. In addition to known manifestations of TSS, to our knowledge this is the first report about development of polyserositis in this disease. Tumor necrosis factor (TNF) was elevated at initial evaluation and fell under treatment with cortisone. This finding is in contrast to in-vitro observations. We believe that the use of cortisone in TSS warrants further investigation.