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At least 1,513 records · Page 84Linked to original sources
PubMed2000

Desert bighorn sheep mortality due to presumptive type C botulism in California.

During a routine telemetry flight of the Mojave Desert (California, USA) in August 1995, mortality signals were detected from two of 12 radio-collared female desert bighorn sheep (Ovis canadensis) in the vicinity of Old Dad Peak in San Bernardino County (California). A series of field investigations determined that at least 45 bighorn sheep had died near two artificial water catchments (guzzlers), including 13 bighorn sheep which had presumably drowned in a guzzler tank. Samples from water contaminated by decomposing bighorn sheep carcasses and hemolyzed blood from a fresh bighorn sheep carcass were tested for the presence of pesticides, heavy metals, strychnine, blue-green algae, Clostridium botulinum toxin, ethylene glycol, nitrates, nitrites, sodium, and salts. Mouse bioassay and enzyme-linked immunosorbent assay detected type C botulinum toxin in the hemolyzed blood and in fly larvae and pupae. This, coupled with negative results from other analyses, led us to conclude that type C botulinum poisoning was most likely responsible for the mortality of bighorn sheep outside the guzzler tank.

Animals↗
PubMedDate not supplied

Neuromuscular activation and RPE in the quadriceps at low and high isometric intensities.

INTRODUCTION: The purpose of this study was to examine neuromuscular activation and ratings of perceived exertion (RPE) at 10% and 80% quadriceps MVC in healthy males. METHODS: Seventeen college-aged volunteers (mean age = 22.6 years, mean height = 178.9 cm, mean weight = 78.8 kg) were assessed for isometric EMG activity of the vastus medialis (VM) and vastus lateralis (VL) at 10% and 80% MVC, and RPE at 80% MVC. Perceived exertion was measured with a modified category ratio scale (CR-10) and was anchored with 1 high and 1 low anchor. Raw EMG signals were sampled via telemetry (rate = 1,000 Hz) and integrated (3 sec) for each contraction for each muscle (bandpass = 16-500 Hz, CMRR = 130 dB). A one-sample t-test was performed for each variable and 95% confidence intervals were calculated. RESULTS: Means and CI for each variable are as follows: 10% MVC VM IEMG (t16 = 5.05, p < 0.001, .95 CI = 3.11 +/- 1.3), 80% MVC VM IEMG (t16 = 22.51, p < 0.001, .95 CI = 73.2 +/- 6.89), 10% MVC VL IEMG (t16 = 8.10, p < 0.001, .95 CI = 9.41 +/- 2.47), 80% MVC VL IEMG (t16 = 39.56, p < 0.001, .95 CI = 87.32 +/- 4.68), and 80% MVC RPE (t16 = 11.85, p < 0.001, .95 CI = 5.24 +/- 0.93). DISCUSSION: The major findings illustrate an apparent underestimation of RPE at 80% MVC for the quadriceps. Neuromuscular activation appears to be lower than the expected force output at both intensities for the VM while VL activation corresponded closely at 10% MVC and was higher at 80% MVC.

Adult↗
PubMed1999

The penetration characteristic of radio wave frequencies from oral cavities.

Recently many radio telemetry systems have been inserted into oral cavities and have been used to send data to receivers. Although various frequencies were used in those systems, there has been no report about the most effective penetrative frequency in the human body. In this study, we observed the penetration of radio waves from oral cavities and compared the efficiency of different frequencies. We selected 11 edentulous persons as subjects and the frequencies ranged from 1 to 150 MHz. Although the attenuation gradually increased with the increase of frequency in most cases, we observed that there were effective resonance-like frequencies in three subjects and the frequency differed from person to person. This phenomenon was only observed when receiving antennas were set beside the mouth and not observed when the antennas were set about 1 m away from subjects. Therefore, it is considered that this phenomenon was produced by the relationship between the transmitting antenna and the receiving antenna. This result suggested that there were effective resonance-like frequencies in the case of radiation from edentulous oral cavities.

Aged↗
PubMed1978

[Tele-electrosubcorticogram study of reactions to vestibular stimulation in neurosurgical clinical practice].

In connection with stereotactic examinations and operations, mainly in certain forms of epilepsy, the electro-subcorticogram under, vestibular stimulations was recorded by telemetry. The amount of informat ion obtained was analysed by electronic data processing. A number of vegetative parameters and the electro-oculogram could be recorded at the same time. Regular bioelectric reaction of the desynchronisation type or of the oscillation depression type were found. In the presence of focal or generalised convulsions, a weakening of the epileptic discharges were observed under labyrinthine stimulation. Also the sense of rotation leads to special influences. The method is also of importance for the postoperative phase as it represents an adaptation of the requirements of modern living conditions (acute accelerations, breaking and changes in direction). Finally, information about the dominance of interfocal relations can also be obtained.

Electroencephalography↗
PubMed2000

Auras, seizure focus, and psychiatric disorders.

OBJECTIVE: The goal of this study was to assess the types of auras and their associations with the focus of seizures in 144 consecutive adult patients with partial epilepsy refractory to medical treatment. The association of frequency and type of aura with a psychiatric disorder was also studied. BACKGROUND: The nature of the aura, its association with the seizure focus, and its relation with emotions and behavioral dysfunction have received relatively little attention, and remain controversial. METHODS: Patients were admitted to an epilepsy investigation unit for detailed observation of their seizures and type of aura. Patients underwent standard electroencephalographic telemetry, including implanted subdural electrodes, if necessary, to delineate the seizure focus. The auras were classified into nine categories. All patients had an independent clinical psychiatric interview for a Diagnostic and Statistical Manual, Third Edition-Revised (DSM-III-R)-based diagnosis. RESULTS: Of the 144 patients studied, 111 (77.1%) had one or more symptoms during the aura and 33 (22.9%) had no aura. The most frequent aura types were viscerosensory (47 cases [32.6%]), experiential (44 cases [30.6%]), and cephalic (21 cases [14.6%]). A temporal lobe focus was present in 116 (80.5%) patients. Only experiential auras were significantly associated with a temporal lobe seizure focus (33 of 44 cases). A DSM-III-R psychiatric diagnosis was present in 74 (51.4%) patients. Of the 116 patients with a temporal lobe focus, 60 (50.2%) had a DSM-III-R psychiatric diagnosis. Patients with two or more auras were significantly more likely to have a psychiatric diagnosis (70.2%) compared with those with one aura (39.1%) or no aura (48.5%). A significant association between experiential auras and psychiatric morbidity was seen. CONCLUSIONS: Auras occurred in a majority of patients with a treatment-refractory partial epilepsy who were hospitalized for assessment of their seizure focus for possible surgical candidacy. Two or more auras were associated with a psychiatric diagnosis as was the presence of an experiential aura. Experiential auras were most common in temporal lobe epilepsy. Approximately half the patients, irrespective of seizure focus, had an associated psychiatric morbidity.

Adolescent↗
PubMed2000

Radiotelemetric evaluation of hemodynamic effects of long-term ethanol in spontaneously hypertensive and Wistar-Kyoto rats.

This study determined the hemodynamic effects of chronic ethanol in telemetered freely moving age-matched spontaneously hypertensive (SHR) and Wistar-Kyoto (WKY) rats. Changes in blood pressure (BP), heart rate (HR), and plasma norepinephrine (as index of sympathetic activity) were evaluated in pair-fed rats receiving liquid diet with or without ethanol (5%, w/v) for 12 weeks. The SHRs exhibited higher baseline BP and lower HR compared with WKY rats. When normalized for body weight, daily ethanol intake was higher in SHRs compared with WKY rats. However, blood ethanol concentration was similar except for a higher level in SHRs at weeks 7 through 9. Ethanol had no effect on BP in WKY rats but caused decreases in BP in SHRs that reached a maximum (approximately 30 mm Hg) at week 5 and remained thereafter. Ethanol also caused reductions in the BP variability and the circadian fluctuations in BP in SHRs but not in WKY rats. Plasma norepinephrine levels were elevated by ethanol in WKY rats, but not in SHRs. The HR was not affected by ethanol in SHRs and showed increases in WKY rats. These findings suggest that chronic ethanol feeding differentially affects BP in SHRs (hypotension) and WKY rats (no effect). The lack of a hypotensive response to ethanol in WKY rats may relate, at least partly, to the associated sympathoexcitation. The present study used the telemetry technique for BP measurement, which eliminates the confounding and stressful effects of other conventional techniques.

Animals↗
PubMed2000

The use of telemetric oximetry in the clinical setting.

The reliability and ease of use of a combined functions-cardiac telemetry and telemetric pulse oximetry system was evaluated in a four phase investigation. This technology was assessed favorably for use in the care of patients on continuous epidural and patient-controlled analgesia.

Adolescent↗
PubMed2000

Cardiovascular parameters telemetrically measured during pregnancy, parturition, and lactation in a common marmoset (Callithrix jacchus).

Here we present the first report of heart rate, blood pressure, and locomotive activity of a female common marmoset (Callithrix jacchus) that was moving freely in its home cage during gestation, parturition, and lactation. We collected the data by using a miniaturized telemetry and data-acquisition system (Data Sciences, St. Paul, MN) that had been adapted for marmosets (1). The parameters were recorded continually from 12 days before to 15 days after parturition. Parturition lasted about 3.5 h, during which marked changes in heart rate, systolic blood pressure, and diastolic blood pressure occurred. To obtain control values, we again measured these parameters for 13 days during a "physiologically neutral" phase (4 months after parturition), when the female was neither pregnant nor lactating. Heart rate was 200% higher, systolic blood pressure was 25% higher, and diastolic blood pressure was 75% higher during parturition than during the neutral phase.

Animals↗
PubMed1997

[The technology of real time telemetring and monitoring multi-channels ECGs through public telephone network].

In this essay a kind of technology of real time telemetring and monitoring multi channels ECGs through public telephone network is presented. Two limb leaders (I and II) ECG signals are transmitted from the sender at first. After they are received by the receiver the other four limb leaders are calculated by computer in the basis of the relation among the limb leaders, the received waveform and the calculated waveform are just the same as those described directly by Electro Cardiograph. After the limb leaders ECG signals (34 s) are transmitted, two selectable thorax leaders ECG signals are transmitted for 34 seconds after automatically changing the leaders. The received ECG waves are displayed on screen real time, shifting smoothly. After transmission doctors may make diagnoses and give some suggestion for treatment. Thus, telemetrying and monitoring multi channels ECGs is realized.

Electrocardiography↗
PubMed1997

[The development of ECG trans-telephone popular monitoring system].

In this essay a new kind of ECG telemetry and monitoring system based on public telephone network is presented, which is able to transfer four channels of ECG of two patients to monitoring center sited at hospital synchronizingly. At the same time doctors may make diagnosis and give instruction for treatment. The system has the functions of real time sample, reviewing, freezing, store, windows, and printing, etc.

Electrocardiography↗
PubMed1975

Multichannel biotelemetry systems for use in EMG studies, particularly in locomotion.

The authors describe their experience with the different types of telemetry systems, applicable for locomotion studies and other similar areas of research. They describe the differences between frequency modulation (FM) systems and time-domain multiplexing (PAM) systems. They discuss the advantages and the disadvantages of each of these systems, particularly as applied to the transmission of EMG signals.

Electromyography↗
PubMed1975

Locomotion studies as an aid in clinical assessment of childhood gait.

A clinical locomotion laboratory has been developed to provide quantitative information in the management of gait disorders. The biomedical engineering development of this system identified two major clinical constraints: (a) the need for instrumentation that would not alter the natural gait of the patient and (b) the need for data-processing techniques that would permit analysis and correlation of the large volume of electromyographic (EMg) and kinematic information. The net result has been a unit that incorporates a multichannel telemetry system to capture the EMG and foot-switch information and a television computer system to handle the kinematic information. Gait studies on children with hemiparesis, muscular dystrophy and cerebral palsy have yielded quantitative EMG and kinematic information on the pathomechanics of ambulation in these disorders. Because the information obtained is quantitative, an accurate measure of improvement (or lack of it) after treatment can be documented. Therefore, the locomotion laboratory may have an important role in the preoperative and postoperative evaluation of children whose abnormal gait may require surgical corrective procedures or rehabilitative treatment including the use of prostheses or orthoses.

Adolescent↗
PubMed2002

[Electrically evoked auditory nerve compound action potentials in Nucleus CI24M cochlear implant users].

OBJECTIVE: To study the feasibility and clinical applicability of electrically evoked auditory nerve compound action potentials (ECAP) in young patients with Nucleus CI24M cochlear implants. METHOD: ECAPs have been recorded from 37 Nucleus CI24M cochlear implant users in response to monopolar electrical stimulation of the cochlea by using the neural response telemetry(NRT) software and the hardware. Behavioral thresholds and maximum comfortable levels were measured in 12 of those patients. RESULT: ECAPs could be recorded in 87.6% of all patients. Good relations were observed between ECAP threshold and behavioral threshold, but poor relations between ECAP threshold and the impedance of different electrodes. We also observed growth functions and threshold variations of ECAP across subjects for a given place as well as across electrodes within a subject. These findings might be that these particular physiological measures are related to the number of living neural fibers and the excitability of the auditory nerve to electrical stimulation. CONCLUSION: ECAPs were proved to be useful in adjusting the stimulation parameters of the cochlear implant speech processor in order to maximize an individual's performance with the device, especially in young children.

Action Potentials↗
PubMed2002

A comparison of body temperature changes due to the administration of ketamine-acepromazine and tiletamine-zolazepam anesthetics in cynomolgus macaques.

Two commonly used anesthetic combinations, ketamine acepromazine and tiletamine-zolazepam, were compared to identify their effects upon body temperature in cynomolgus macaques. We allocated 30 cynomolgus macaques previously implanted with subcutaneous telemetry devices into two groups of 15 animals. Baseline temperature data were collected for 3 days before administering anesthesia to establish normal diurnal temperature patterns for each monkey. Each group then was anesthetized with either ketamine-acepromazine or tiletamine-zolazepam, and their body temperatures were recorded at 15-min intervals. Both groups had marked decreases in body temperature, with the greatest decreases in the tiletamine-zolazepam group. In addition, both groups had notable post-anesthesia elevations in body temperature that often lasted for more than 24 h postinduction.

Acepromazine↗
PubMed2002

Circadian rhythms in airline pilots submitted to long-haul transmeridian flights.

BACKGROUND: Circadian rhythms shift out of phase after transmeridian flights. Desynchronization between body rhythms and the environment is linked to jet lag, which depends on age, flight direction, and number of time zones crossed. METHODS: To investigate this problem in airline pilots, we performed a multivariate analysis of their circadian systems during Madrid-Mexico-Madrid flights (-7 time zones, n = 12) and Madrid-Tokyo-Madrid flights (+8 time zones, n = 21). Telemetry was used to record pilots' activity, skin temperature, and heart rate, obtaining 6 d of continuous data, including 2 d before the flight, the flights themselves, 2 d at the stopover, and 1 d after the return flight. Time series were analyzed by cosinor, and the resulting parameters of the rhythms were compared by ANOVA and Tukey contrasts in every category formed by the age groups (under and over 50 yr old) and flight direction groups. Subjective time estimation of short, intermediate, and long intervals was recorded. Other psychological variables were measured, including anxiety, tiredness, and performance. RESULTS AND CONCLUSIONS: Activity/rest and heart rate rhythms appeared to be linked to a "weak oscillator." Temperature rhythms manifested a rigid response after the phase shifts of the light/dark cycle, closely related to the biological clock. Subjective time appreciation tended to be overestimated without exhibiting a clear circadian component, but attributable to fatigue and stress. Psychometric evaluation showed that desynchronization affected all the pilots. Some results showed an age-related variability with a more marked influence in younger pilots. No consistent effects regarding flight direction were found.

Activity Cycles↗
PubMed2002

[Lengthy epidural blockade and intestinal motor function in the early postoperative period].

The telemetry method of registration of the intraintestinal pressure was used for the investigation of the motor function of the intestine under condition of continuous epidural blockade (CEB) with Trimekain at early terms after operations on the stomach for ulcer disease. It was found that the motor cycle structure of the small and sigmoid bowels within the first three days after resection of the stomach and truncal vagotomy was not substantially changed under the influence of CEB. A pronounced stimulating effect of the epidural blockade manifested itself as an improvement of the main quantitative parameters of intestinal motility. The character of these changes in the small and sigmoid bowels was the same and did not depend on intactness of vagus nerves. The combined mechanism of the influence of CEB on intestinal motility includes analgesia, improved respiratory function, greater volume of mesenterial circulation and the influence on the intramural nervous system and muscle apparatus of the intestine.

Anesthesia, Epidural↗
PubMed1975

An implantable transmitter for monitoring heart rate and respiratory frequency in diving ducks.

An implantable telemetry transmitter is described for monitoring respiratory frequency and heart rate in animal physiological studies. The ECG is transmitted directly while the respiratory signal, derived from the temperature variation of the air in the respiratory tract, modulates the frequency of a subcarrier oscillator. A magnetic switch allows the implanted device to be switched on and off remotely. Details are given of the high packing density achieved by a modified cordwood method of construction. This system is being used to investigate the changes in heart rate and respiratory frequency associated with spontaneous diving in ducks, and typical results are presented.

Animals↗