Search results for "laser"
showing 10 items of 3161 documents
Blood flow velocity waveforms of the fetal middle cerebral artery in a normal population: reference values from 18 weeks to 42 weeks of gestation
2002
The aim of this prospective cross-sectional study was to establish new Doppler reference curves for peak blood flow velocities (Vmax, Vmean, Vmin) and impedance indices (PI, RI) of the middle cerebral artery at 18-42 weeks of gestation by an automatic wave form analysis integrated into the ultrasound device. In 962 low-risk pregnancies, blood flow velocities were derived from the middle cerebral artery with pulsed color Doppler ultrasonography. Reference curves were constructed for the individual parameters based on a growth function from a four-parameter class of monotonic continuous functions according to the smallest square principle for maximum blood flow velocities, as well as on a pol…
Differential nociceptive deficits in patients with borderline personality disorder and self-injurious behavior: laser-evoked potentials, spatial disc…
2003
Approximately 70-80% of women meeting criteria for borderline personality disorder (BPD) report attenuated pain perception or analgesia during non-suicidal, intentional self-mutilation. The aim of this study was to use laser-evoked potentials (LEPs) and psychophysical methods to differentiate the factors that may underlie this analgesic state. Ten unmedicated female patients with BPD (according to DSM-IV) and 14 healthy female control subjects were investigated using brief radiant heat pulses generated by a thulium laser and five-channel LEP recording. Heat pulses were applied as part of a spatial discrimination task (two levels of difficulty) and during a mental arithmetic task. BPD patien…
Imaging photoplethysmography for clinical assessment of cutaneous microcirculation at two different depths
2016
The feasibility of bispectral imaging photoplethysmography (iPPG) system for clinical assessment of cutaneous microcirculation at two different depths is proposed. The iPPG system has been developed and evaluated for in vivo conditions during various tests: (1) topical application of vasodilatory liniment on the skin, (2) skin local heating, (3) arterial occlusion, and (4) regional anesthesia. The device has been validated by the measurements of a laser Doppler imager (LDI) as a reference. The hardware comprises four bispectral light sources (530 and 810 nm) for uniform illumination of skin, video camera, and the control unit for triggering of the system. The PPG signals were calculated and…
Dipole Source Analysis of Laser-Evoked Subdural Potentials Recorded From Parasylvian Cortex in Humans
2003
The location of the human nociceptive area(s) near the Sylvian fissure is still controversial in spite of evidence from imaging and evoked potential studies that noxious heat stimuli activate somatosensory areas in that region. Some studies have suggested the secondary somatosensory cortex (SII) on the upper bank of the Sylvian fissure posterior to the central sulcus, others the anterior insula or parietal area 7b. In this study, we applied dipole source analysis techniques to laser-evoked potentials (LEPs) that were recorded from subdural grid electrodes in three patients. As a functional marker, auditory-evoked potentials (AEPs) with a generator on the opposite bank of the Sylvian fissur…
Comparison of tear protein levels in breast cancer patients and healthy controls using a de novo proteomic approach
2012
Noninvasive biomarkers are urgently needed for early detection of breast cancer since the risk of recurrence, morbidity and mortality are closely related to disease stage at the time of primary surgery. In the past decade, many proteomics-based approaches were developed that utilize the protein profiling of human body fluids or identification of putative biomarkers to obtain more knowledge on the effects of cancer emergence and progression. Herein, we report on an analysis of proteins in the tear fluid from breast carcinoma patients and healthy women using a de novo proteomic approach and 25 mixed samples from each group. This study included 25 patients with primary invasive breast carcinom…
Modeling Human Endometrial Decidualization from the Interaction between Proteome and Secretome
2011
Context: Decidualization of the human endometrium, which involves morphological and biochemical modifications of the endometrial stromal cells (ESCs), is a prerequisite for adequate trophoblast invasion and placenta formation. Objective: This study aims to investigate the proteome and secretome of in vitro decidualized ESCs. These data were combined with published genomic information and integrated to model the human decidualization interactome. Design: Prospective experimental case–control study. Setting: A private research foundation. Patients: Sixteen healthy volunteer ovum donors. Intervention: Endometrial samples were obtained, and ESCs were isolated and decidualized in vitro. Main Ou…
Autonomic regulation of nasal vessels during changes in body position
1994
The effects of postural changes on nasal airflow and nasal capillary blood flow were investigated in 15 healthy volunteers. Measurements were performed following nasal application of saline solution (control), the alpha-1 receptor antagonist prazosin, the alpha-2 receptor antagonist yohimbine, and after application of both prazosin and yohimbine. Nasal airflow in the control experiments did not significantly differ in the upright (362 +/- 166 ml/s), dorsally recumbent (350 +/- 167 ml/s) and 70 degrees head down position (311 +/- 167 ml/s). Following application of prazosin, nasal airflow was reduced to 223 +/- 121 ml/s in the upright position. Prazosin treatment significantly reduced nasal …
Nuclear magnetic resonance imaging of airways in humans with use of hyperpolarized3He
1996
The nuclear spin polarization of noble gases can be enhanced strongly by laser optical pumping followed by electron-nuclear polarization transfer. Direct optical pumping of metastable 3He atoms has been shown to produce enormous polarization on the order of 0.4-0.6. This is about 105 times larger than the polarization of water protons at thermal equilibrium used in conventional MRI. We demonstrate that hyperpolarized 3 He gas can be applied to nuclear magnetic resonance imaging of organs with air-filled spaces in humans. In vivo 3 He MR experiments were performed in a whole-body MR scanner with a superconducting magnet ramped down to 0.8 T. Anatomical details of the upper respiratory tract …
Neonatal outcome following long-distance air travel for fetoscopic laser coagulation treatment of twin-to-twin transfusion syndrome
2011
Abstract Objective To investigate the impact of undertaking long-distance air travel to a specialized medical center while pregnant in order to undergo fetoscopic laser coagulation (FLC) for twin-to-twin transfusion syndrome (TTTS). Methods A retrospective cohort study was conducted of women with TTTS who travelled by air (n = 16) or land (n = 61) to the Centre of Perinatal Diagnosis and Microinvasive Fetal Surgery, Mainz, Germany, between January 1, 2006, and December 31, 2010. All women underwent FLC on arrival at the study center. Neonatal outcome, postoperative neonatal survival rates, and rates of adverse effects were recorded. Results The postoperative survival rate for a single twin …
Femtosecond laser versus mechanical microkeratome laser in situ keratomileusis for myopia: Metaanalysis of randomized controlled trials.
2011
Purpose To examine differences in efficacy, accuracy, safety, and changes in aberrations between femtosecond and mechanical microkeratome laser in situ keratomileusis (LASIK) for myopia. Setting Department of Ophthalmology, Shanghai First People's Hospital Affiliated to Shanghai Jiaotong University, Shanghai, China. Design Evidence-based manuscript. Methods Data sources, including PubMed, Medline, EMBASE, and Cochrane Controlled Trials Register, were searched to identify potentially relevant prospective randomized controlled trials. Primary outcome measures were efficacy (uncorrected distance visual acuity ≥20/20), accuracy (±0.50 diopter mean spherical equivalent), and safety (loss of ≥2 l…