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Biomedical subjects

H Menduke

Publications and source records attributed to H Menduke.

At least 37 records · Page 2Linked to original sources
PubMed1986

Factors affecting descending binaural loudness balances as a manifestation of adaptation.

Three trained adults with normal hearing were exposed to a continuous 1-kc/s pure tone in both ears simultaneously at 100 db SPL. In the R ear the tone was attenuated at 1 db/sec until it was inaudible. In the L ear the tone was attenuated at 5 db/sec, and S was asked to adjust the loudness in the L ear by pushing and releasing a hand-switch as in Bekesy audiometry in order to maintain so far as possible a binaural loudness match. At every reduction of 10 db in the R ear (i.e., every 10 sec) the SPL to the L ear was measured from the Bekesy-type tracing which yielded binaural loudness match. While there were inter-subject variations, for all Ss the level of the tone in the L ear (5 db/sec) had to be increased above physical equality for equal loudness, indicating the presence of more rapid adaptation in that ear. The disparity in 2 Ss progressed regularly from near zero after 10 sec to 16-17 db after 1 min. For 1 S, a constant disparity of about 6 db existed throughout the session. Binaural loudness balances by this descending method may be considered a manifestation of normal adaptation, confirming a previous report (Harbert and Young, J. Acoust. Soc. Am., 1968, 43, 752-756) for threshold differences produced by various attenuation rates at various suprathreshold starting levels. An analogous ascending procedure with 1 S yielded results susceptible to the same interpretation.

Acoustic Stimulation↗
PubMed1985

Medical management of congenital nasolacrimal duct obstruction.

One hundred thirteen consecutive children seen with congenital nasolacrimal duct obstruction were treated with local massage and topical antibiotic ointment. The obstruction was resolved in 107 patients within eight months of initiation of this form of management. Nearly all of the children were spared a surgical procedure that probably would have been performed if early probing of the nasolacrimal system had been advocated.

Erythromycin↗
PubMed1985

A Bekesy descending-only procedure: effects of attenuation rate and step size, and starting level.

Bekesy fixed-frequency thresholds for pulsed and continuous tones at 1 kc/s yielded by a descending-only technique were compared for suprathreshold starting levels of 38, 58, 78, and 98 db SPL, and attenuation rates of 1, 2, 4, and 8 db/sec with associated attenuation steps of 0.25, 0.5, 1, and 2 db, respectively, with 3 normal-hearing adults. For pulsed tones of 250 msec (duty cycle 50%), thresholds were not significantly affected by attenuation rate/step size or by starting level. However, for continuous tones, increasing attenuation rate/step size yielded better thresholds for a given starting level. Decreasing starting level yielded better thresholds for a given attenuation rate/step size. Thus, deteriorated thresholds were yielded by the slower attenuations/step sizes and by the higher starting levels. These data may be explained as a manifestation of normal adaptation. The similar relative effects found here of attenuation rate/step size and of starting level, as compared to the data of an earlier study (Harbert and Young, 1968) which used the traditional up-down Bekesy method of threshold tracing lend support to the possible future clinical use of a descending-only technique.

Audiometry↗
PubMed1985

Medical management of congenital nasolacrimal duct obstruction.

A consecutive series of 113 infants seen with congenital nasolacrimal duct obstruction were treated with local massage and topical antibiotic ointment. In 107 of the infants the obstruction was resolved within 8 months of initiation of this form of management. Nearly all of the infants were spared a surgical procedure that probably would have been performed if early probing of the nasolacrimal system had been advocated.

Combined Modality Therapy↗
PubMed1984

Hearing loss and intermittent noise exposure.

Previous studies of occupational hearing loss have led to the belief that a typical hearing loss pattern results regardless of the noise source. Classically, the frequencies between 3,000 and 6,000 Hz are affected first. Subsequently, as the exposure continues, the hearing loss spreads to involve lower frequencies (speech) and 8,000 Hz. Although it has been assumed that this progression is typical for occupational hearing loss, it must be remembered that these studies were based chiefly on continuous exposure to noise in areas such as textile mills and paper factories. Practical experience in industry and review of millions of audiograms have shown that the classic audiogram is not as common as generally thought, especially in workers subjected to intermittent noise exposure such as chipping. In this investigation, 12,000 workers were screened to find 295 who met the strict criteria, the most important of which was intermittency of noise exposure. Most of the subjects were exposed to jackhammer noise that peaked at about 118 dBA. The study reveals a substantially different pattern of hearing loss from that reported previously. Intermittent exposure to intense noise results in very severe loss in high frequencies but relatively little or no hearing loss in the lower frequencies, even after many years of exposure. It remains to be determined whether this pattern of hearing loss results from intermittent exposure to all types of noise or only from those kinds investigated in this study. It is speculated that frequent rest periods permit the ear to protect itself from damage in the speech frequencies. This concept opens many possible avenues for preventing hearing handicap in industrial situations.

Adult↗
PubMed1981

Long-term treatment of hypertension with methyldopa. I. Study objectives and design.

In this retrospective study, a group of 435 patients provided meaningful analyses of blood pressure and dosage data for treatment periods of up to 4.5 years. The protocol, study objectives, and pretreatment demographic characteristics of the group are summarized in this report, which is the first in a series in this issue describing the results of this survey.

Adolescent↗
PubMed1980

The effect of contrast media of low osmolality on the peripheral arterial blood flow in the dog.

The intravascular contrast media in current use are solutions of salts of tri-iodinated substituted benzoic acids. Haemodynamic changes following injection of these contrast media are due mainly to their high osmolar concentration which is five to eight times physiological levels. In this study we compare the effect in dogs on femoral arterial flow following femoral arterial injection of three new low osmolality contrast media (Amipaque, Iopamidol and Hexabrix) compared to conventional contrast media (Coronary 280). Conventional salts such as Conray 280 cause a marked vasodilatation and increase in femoral blood flow to about twice pre-injection levels. The three new low osmolality contrast media cause much less vasodilation and increase in femoral blood flow (+32%). There was no significant difference between the effects of any of the three new media. The experiment suggests that any of three new low osmolality contrast media should be suitable for femoral arteriography as they cause much less vasodilatation (and therefore discomfort) than conventional contrast media. Our results do not indicate a preference for any of the three new contrast agents.

Animals↗
PubMed1980

Anti-inflammatory drug treatment of Crohn's disease: a prospective evaluation of 100 consecutively treated patients.

We have analyzed the results of anti-inflammatory drug treatment of 100 consecutively treated patients with Crohn's disease. The disease affected the colon in 12 patients, small bowel in 36, and both colon and small intestine in 52. Thirty-two patients had had a prior resection of Crohn's disease. According to an adaptive design, patients were treated with sulfasalazine if able to take oral drugs; with steroids if unable to take, or unresponsive to, sulfasalazine; and with added azathioprine if unresponsive to sulfasalazine and steroids and unsuitable for surgery. Drug regimens included sulfasalazine alone in 39 patients, steroids alone in seven patients, both sulfasalazine and steroids in 43 patients, and added azathioprine in 11 patients. All patients completed at least 1 year, or were regarded as treatment failures after 3 months of drug treatment. We analyzed clinical and radiographic responses. Significant improvement occurred in all categories of patients: complete or partial clinical remission was observed in 79%, and complete or partial radiographic regression was observed in 55%; 30% of patients were not reexamined radiographically and the remainder showed no improvement. Our study suggests that properly selected anti-inflammatory drug therapy has definite benefits and is indicated for patients with Crohn's disease.

Adult↗
PubMed1979

Lipoprotein X and alkaline phosphatase as indicators of cholestasis.

Lipoprotein X is considered to be an indicator of cholestasis, but its clinical usefulness is unclear owing to different methods of measurement in use and varying definitions of cholestasis. We investigated the reliability of the qualitative determination of lipoprotein X in predicting cholestasis, defined here as the presence of stainable bile in tissue sections. Liver tissue and serum were collected from 42 patients. Patients were divided into those who did and those who did not have stainable bile in tissue sections. Lipoprotein X was demonstrated by electrophoresis and polyanion precipitation. Lipoprotein X in serum correlated with the presence of stainable bile (p = 0.0006). A normal range of alkaline phosphatase values correlated with the absence (p = 0.04), but elevated values did not correlate with the presence of stainable bile. In patients known to have elevated alkaline phosphatase, the presence of lipoprotein X still correlated with the presence of bile (p = 0.008). We conclude that lipoprotein X is a reliable indicator of cholestasis and that it is more useful than alkaline phosphatase in this application.

Alkaline Phosphatase↗
PubMed1975

Early intrauterine development: I. The rate of growth of Caucasian embryos and fetuses between the 6th and 20th weeks of gestation.

Liberalization of abortion laws in various countries and states of Europe and America has offered an opportunity for the study of the correlations between menstrual age and the rate of bodily development of human embryos and fetuses. In several institutions where local bylaws mandated the consent of the patients requesting therapeutic abortion to pathological investigation of the products of conception, various parameters of growth were measured systematically. These included crown-rump and foot lengths and body weight. The analysis of the data indicated that in the embryosic stages of development the rate of growth is substantially slower than it had been assumed previously. In the more advanced fetal stages of development the findings supported the validity of the long-established standard of Streeter. Since the current study has been based on apparently normal gestations of healthy women, whereas earlier data had rested, to a great extent, on spontaneously aborted and extopic embryon and fetuses, it seems evident that pathological specimens are not suitable for the purpose of establishing reliable standards of normal intrauterine growth rate. The present data support the suggestion, based on various experimental and clinical observations, that pathological gestations often result from abnormal ovulations that occur at times other than the mid-cycle and that such conceptions are frequently followed by a bleeding episode that simulates menstruation. It is likely that the inclusion of a high number of such cases biased the results of earlier investigations concerning embryonic growth rate on account of the frequent incidence of erroneous menstrual histories. The material available did not permit the extension of the investigation beyond the 20th week of gestation. It appears, however, that the average growth rate in the mid-trimester may be slower than the data adopted by the American Academy of Pediatrics would indicate. The possible causes of some phenomena observed in the course of the investigation, such as unexplained scatter of growth-rate patterns at all developmental stages and discrepancies among various literary data, have been discussed in some detail. While a tentative attempt has been made to correlate the investigated parameters of fetal growth with biparietal diameters of the head, a measurement accessible to direct assessment by sonography during pregnancy, the necessity of improving these standards through a prospective study has been emphasized.

Abortion, Therapeutic↗