Psychological and Physiological Variables Associated With Large Magnitude Voluntary Heart Rate Changes

Forty subjects, given binary and proportional auditory and visual feedback and asked to raise and lower their heart rate on signal, were able to produce increases of up to 46 bpm and decreases of up to 14 bpm, with a mean increase over 5 experimental days of 11 bpm and a decrease of 5 bpm. Increases in both diastolic and systolic blood pressure and increases in skin potential level and number of skin potential responses accompanied voluntary increases in heart rate but not decreases. Subjects with the highest resting heart rate variability and skin potential level were best able to raise their heart rate. Subjects with the highest resting heart rate and highest resting heart rate variability were best able to decrease the heart rate. Subjects with high Ego Strength scores (or low Welsh's Factor A scores) on the MMPI were best able to control their heart rate. The Ego Strength score, resting heart rate, and resting heart rate variability were all significantly intercorrelated. Subjects showed marked individual differences in ability to control heart rate, although there was a significant correlation between ability to raise and ability to lower heart rate.     

Mandibular position during children's defective /s/ productions

Mandibular displacement during /s/ production was monitored via a mercury strain gauge which was taped to the face of two normally articulating and six /s/-misarticulating children. Simultaneous audio and jaw displacement visicorder traces were produced from an FM-tape recording of each experimental session, and were subsequently analyzed. Results indicated that various /s/-misarticulating subgroups exhibit different mandibular positions during /s/-production, and phonetic contextual effects upon mandibular position also vary by articulatory type.     

Comparison of whole lung tomography and computed tomography for detecting pulmonary nodules.

Detecting pulmonary metastasis is important when planning surgical therapy, radiotherapy, or chemotherapy in patients with known malignancy. A series of 91 patients was studied by both whole lung tomography and computed tomography (CT) of the lungs. More pulmonary nodules were detected with CT than with whole lung tomography in 32 (35%) of the patients. Of the 91 patients in the study, 31 had resection of some or all of the pulmonary nodules. In 27 patients, the nodules were primary or metastatic malignant lesions. Bilateral pulmonary nodules were detected with CT in 13 patients when whole lung tomography had demonstrated nodules in only one lung. CT has replaced whole lung tomography as the method preferred by the authors for detecting pulmonary nodules in selected patients at risk to develop pulmonary metastasis.     

Chenotherapy for gallstone dissolution. I. Efficacy and safety.

Clinical experience with chenodeoxycholic acid therapy for dissolving gallstones is reported, with particular attention to determinants of response. Of 12 patients receiving 15 mg/kg/day or more, ten responded (83%); only 15 of 40 patients (38%) receiving less than 15 mg/kg/day responded. Large solitary stones and stones in gallbladders that visualized poorly after oral cholecystography had a lower response rate. Radiopaque stones did not respond in 18 patients. Five of ten patients with stones in the common bile duct responded. Small, dose-related elevations in SGOT were the only biochemical abnormality observed. Liver biopsy specimens showed no notable abnormality. Diarrhea was an infrequent problem. Stones recurred in three of 15 patients during six to 48 months of observation without treatment. Chenodeoxycholic acid, when given in adequate dosage, continues to appear promising as medical therapy for asymptomatic radiolucent gallstones in radiologically visualizing gallbladders.     

Influence of anaesthetics on tumour-cell kill and repopulation in B16 melanoma treated with melphalan.

The influence of anaesthetics on the in vivo response of B16 melanoma to melphalan was studied using an in vitro cell-survival assay. Three anaesthetics were used, Saffan (Althesin) Sagatal (Nembutal) and Hypnorm. When Saffan was administered to tumour-bearing animals before melphalan there was a significant increase in tumour-cell kill. This effect was not observed with Sagatal or Hypnorm. Maximum increase in tumour-cell kill was achieved when Saffan was administered about 1 h before melphalan, and was dependent on Saffan dose. Clonogenic tumour-cell repopulation after melphalan was rapid (TD - 1 day) and the rate was similar from 2 levels of cell kill. When Saffan was combined with melphalan the repopulation rate was the same as with melphalan alone, and the increased cell kill was reflected in increased growth delay. The in vitro response of B16 melanoma cells to melphalan was unaltered by pretreatment with, or simultaneous exposure to Saffan. The results suggest that the mechanism of the enhanced cell kill in vivo is probably due to an indirect systemic effect, rather than a direct effect on the tumour cells.     

The Use of Electrocutting and Electrocoagulation in Surgery

Electrocutting and electrocoagulation are convenient aids to surgical technique, but their we is avoided by some surgeons because of a believed risk of increased wound morbidity-Medical literature contains little information concerning morbidity after the use of electro-surgery as compared with its occurrence after standard alternative techniques. This paper describes such experiments, which compare tensile strengths of healing wounds and the incidence of intraperitoneal sequel? following extensive use of electrosurgery and use of other alternative procedures.