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L R Morris

Publications and source records attributed to L R Morris.

8 recordsLinked to original sources
PubMed1989

Algorithms, hardware, and software for a digital signal processor microcomputer-based speech processor in a multielectrode cochlear implant system.

Software and hardware have been developed to create a powerful, inexpensive, compact digital signal processing system which in real-time extracts a low-bit rate linear predictive coding (LPC) speech system model. The model parameters derived include accurate spectral envelope, formant, pitch, and amplitude information. The system is based on the Texas Instruments TMS320 family, and the most compact realization requires only three chips (TMS320E17, A/D-D/A, op-amp), consuming a total of less than 0.5 W. The processor is part of programmable cochlear implant system under development by a multiuniversity Canadian team, but also has other applications in aids to the hearing handicapped.

Algorithms↗
PubMed1986

Bicarbonate therapy in severe diabetic ketoacidosis.

Twenty-one adult patients with severe diabetic ketoacidosis entered a randomized prospective protocol in which variable doses of sodium bicarbonate, based on initial arterial pH (6.9 to 7.14), were administered to 10 patients (treatment group) and were withheld from 11 patients (control group). During treatment, there were no significant differences in the rate of decline of glucose or ketone levels or in the rate of increase in pH or bicarbonate levels in the blood or cerebrospinal fluid in either group. Similarly, there were no significant differences in the time required for the plasma glucose level to reach 250 mg/dL, blood pH to reach 7.3, or bicarbonate level to reach 15 meq/L. We conclude that in severe diabetic ketoacidosis (arterial pH 6.9 to 7.14), the administration of bicarbonate does not affect recovery outcome variables as compared with those in a control group.

Adult↗
PubMed1983

Hypopituitarism secondary to cavernous sinus thrombosis.

We present what we believe to be the only documented cases of cavernous sinus thrombosis complicated by acute hypopituitarism and ultimately resulting in limited pituitary ACTH reserve. If pituitary involvement is suspected, replacement therapy should be instituted while awaiting laboratory confirmation. Cavernous sinus thrombosis is a medical and surgical emergency. Its successful therapy is dependent upon prompt recognition, surgical drainage when appropriate, proper antibiotic coverage, and close observation for and prompt treatment of complications and sequelae.

Adrenocorticotropic Hormone↗
PubMed1981

Correlation between plasma and urine glucose in diabetes.

To determine whether semiquantitative glucose measurements of spot urine specimens accurately reflect prevailing plasma glucose levels, we compared reported levels from 400 second-voided urines to simultaneous plasma determinations from 246 adult diabetics. Quantitative urine levels and plasma glucose levels correlated. However, when semiquantitative urinary determinations were compared to plasma glucose stratified into 0 to 149, 150 to 199, and greater than 200 mg/dL, 75% of the urine samples associated with plasma levels from 150 to 199 mg/dL were negative by Diastix, and 16.5% of samples negative by Diastix were in the 200+ mg/dL plasma range. Only 9% of samples from 0 to 149 mg/dL showed any positive Diastix readings. Because of the low sensitivity of semiquantitative methods, we fell that, except for detection of marked hyperglycemia, spot urine glucose determinations are inadequate as the sole means of clinical assessment for management of diabetic patients. Home glucose monitoring may be a better alternative for follow-up of these patients.

Adult↗
PubMedDate not supplied

Efficacy of low-dose insulin therapy for severely obtunded patients in diabetic ketoacidosis.

To evaluate the efficacy of low-dose insulin therapy in cases of severe diabetic ketoacidosis (DKA), we examined admission clinical and biochemical parameters and responses to therapy in 48 diabetic patients who presented with DKA and were randomized to receive either high- or low-dose insulin. There were no differences in the initial clinical and biochemical parameters of the patients, regardless of assignment to low or high dose; however, a subgroup of 13 patients who were classified as severe DKA (based on their presentation in a comatose or stuporous state) had, as expected, more marked clinical and biochemical abnormalities than their alert cohorts. The responses to therapy (rate of glucose decrement and control of acidosis) were comparable in the high-dose and low-dose groups of comatose/stuporous patients and were not significantly different from the noncomatose cohorts. These data indicate that low-dose insulin therapy in severely ill comatose patients is as effective as high-dose.

Adult↗