Search PubMed⌕ Search

Biomedical subjects

S Landau

Publications and source records attributed to S Landau.

At least 55 records · Page 3Linked to original sources
PubMed1989

Neodymium: YAG laser specifications for safe intravesical therapy.

The depth of penetration of a laser beam is a critical factor in determining the therapeutic potential and risks of treatment. Variable parameters of laser energy were applied endoscopically in dog bladders. Although there was a clear trend toward greater depth of necrosis with increased energy, marked variability occurred within each set of energy specifications. Full thickness injuries with penetration depths up to five mm. were observed in some animals at all energy levels above 120 joules. A number of variables affect the penetration depth of a Nd:YAG laser, some of which are difficult to control with precision in an endoscopic setting.

Animals↗
PubMed1988

Social communication patterns of attention-deficit-disordered boys.

This study was designed to compare the social communication patterns of attention-deficit-disordered (ADD) and normal boys. This was accomplished by employing a "TV Talk Show" social role-playing procedure in which the task required different strategies for the roles of "host" and "guest." Groups of ADD and normal elementary-age boys were formed, and each boy was paired with a normal class-mate. Measures of communication competence were coded from videotapes made of subject and partner social interactions while performing both roles. Results indicated that the ADD boys, in contrast to the control group, failed to modulate their social communication behaviors as task demands shifted. Additionally, the behavior of the ADD boys resulted in their normal partners' altering their response patterns in order to maintain the equilibrium in the dyadic interaction. These results suggest that the social behavior of ADD children is relatively independent of environmental requirements and may contribute to the inappropriate responding of others.

Attention Deficit Disorder with Hyperactivity↗
PubMed1987

Pathological findings in mine workers: I. Description of the PATHAUT database.

A computerized system for recording the results of structured, numerically coded autopsy reports on various types of mine workers has been in operation at the National Centre for Occupational Health in Johannesburg since 1975. Historical developments, particularly those associated with compensation for occupational disease, have resulted in very high autopsy rates, especially among whites. Since its inception, the pathology automation (PATHAUT) system has accumulated the results of more than 33,000 autopsies. The data set is described in the hope of stimulating interest in the possible uses of the data and encouraging collaborative research. Some characteristics of the database with potential research implications are discussed. These include differing age and work patterns for blacks and whites and geographic factors with potential influence on whether a body or only the cardiorespiratory organs are sent for examination.

Autopsy↗
PubMed1987

The predictors of emphysema in South African gold miners.

Environmental and host factors have been implicated in the pathogenesis of emphysema. To assess the role of gold mining exposure (an environmental factor) and of various clinical features recorded early in a miner's career (host factors), a case control study was carried out as follows. From whole lung sections made routinely at all full autopsy examinations on South African gold miners, we selected 44 cases of emphysema and 42 controls without emphysema from among men 51 to 71 yr of age who died during 1980 and 1981. Exposure information was gathered and clinical records were reviewed for smoking history, symptoms, and the presence of rhonchi by decade before death. The presence and grade of silicosis (abstracted from the routine autopsy reports) was similar in both groups; so was bronchitis in the 49 cases and controls with histologic material adequate for review. However, cases were on average older, had worked more shifts in high dust, and had smoked more than controls; they had also exhibited symptoms and rhonchi more frequently before 1950, i.e., 30 yr before death. When these factors were examined in a multiple logistic regression analysis, shifts worked in high dust, smoking, and age were all shown to be strong and independent predictors of emphysema at autopsy; prediction, however, was not improved by addition of any of the clinical features examined. These findings agree with previous cross-sectional studies in South African gold miners showing an exposure response relationship between mining service and air-flow limitation measured by lung function tests in life.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1985

Laser Doppler velocimetry as a monitor of cardiac output changes in dogs.

Cutaneous blood flow may be measured utilizing a continuous, noninvasive technique, laser Doppler velocimetry (LDV). Monitoring of cutaneous blood flow by LDV might be a useful method to monitor cardiac output. To test this hypothesis, sequential measurements of cardiac output, LDV, and transcutaneous oxygen (PtcO2) were made on 10 anesthetized dogs during experimental shock. There was significant correlation between LDV and cardiac output, while PtcO2 reflected cardiac output only at low flow states. These results show that, in the animal model, cutaneous LDV is a sensitive and specific method for monitoring cardiac output changes.

Animals↗
PubMed1984

Development of gallstone pancreatitis. The role of the common channel.

Whether bile reflux through a common channel into the pancreatic duct is a causative factor in the development of gallstone pancreatitis is controversial. To address this issue, we have reviewed a consecutive series of cholecystectomies performed with intraoperative cholangiograms. The cholangiograms and the patients' charts were reviewed independently to determine the incidence of a common channel in patients both with and without pancreatitis and to analyze their clinical courses. The group of patients who had pancreatitis showed a common channel in 19 (90%) of 20 cases, while those patients who did not have pancreatitis showed a common channel in 23 (35%) of 66 cases. The patients who had pancreatitis were less likely to have choledocholithiasis than were those patients who did not have pancreatitis, and these patients were less likely to require exploration of the common bile duct.

Ampulla of Vater↗
PubMed1984

A comparison of the social status and social behavior of aggressive and aggressive/withdrawn boys.

The purpose of this study was to clarify contradictory findings concerning the social status of aggressive youngsters. This was undertaken by dividing kindergarten boys into either Aggressive [A] or Aggressive/Withdrawn [A/W] groups, as proposed by Ledingham [1981]. Both groups were found to be high on peer-nominated rejection, but the A group was also high on peer-nominated popularity while the A/W group was low. Similarly, both groups were observed to be high in negative peer interactions, but the A group was also high in positive interactions. It was noted that valuable information regarding the social status and social behavior of aggressive youngsters would be lost if such subgrouping is not undertaken. The relationship between Ledingham 's categorizations and others reported in the literature was discussed.

Aggression↗
PubMed1982

Preschool peer perceptions of the behavior of hyperactive and aggressive children.

To assess if preschool children can successfully identify externalizing symptomatic behaviors in their male classmates, and if these perceptions are associated with peer-rated popularity and rejection, 154 preschool boys and girls were interviewed using a peer nomination procedure. Behavioral data on the same preschool boys (N = 86) were also provided by their respective teachers. Preschool children were capable of providing stable nominations of popularity, rejection, and aggression, boys and girls significantly agreed in their nominations, and these nominations were not a function of the age of the rated child, although they differed somewhat as a function of the age of the rater. Teachers and peers reflected significant convergence in ratings of hyperactivity and aggression and teacher ratings of peer problems significantly agreed with actual peer nominations of popularity and rejection. Boys nominated as aggressive were more rejected by their classmates, whereas boys nominated as hyperactive were either more popular and/or more rejected. Limited evidence for differential patterns of relationships among hyperactivity, aggression, and peer status was obtained for both the peer and teacher data.

Aggression↗
PubMed1978

The parotid and the pancreas. V. Effects of a synthetic prostaglandin analog on parotid gland secretion.

Effects of a synthetic prostaglandin analog--16,16-dimethyl prostaglandin E2 methyl ester (16-diMe-PGE2)--on parotid secretion were evaluated in eight dogs under anesthesia. Graded doses of 16-diMe-PGE2 (0.3, 0.5, 1.0 and 2.5 microgram./kg.) were administered intravenously with the parotid in the resting state or in response to urecholine (intravenous infusion or subcutaneous injections). Profound and prolonged inhibition of volume occurred. Amylase concentration was increased but output was unchanged. Bicarbonate concentration was increased but output was decreased. Nonsteroid inhibitors of endogenous prostaglandin synthesis did not alter these effects. Although these studies do not establish a physiologic role for prostaglandins in the regulation of salivary secretion, they do demonstrate a wide-ranging effect of prostaglandins on the gastrointestinal tract.

Amylases↗