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Biomedical subjects

M J Klein

Publications and source records attributed to M J Klein.

At least 163 records · Page 9Linked to original sources
PubMed1984

Effect of d-amphetamine and diazepam on the greeting behavior of rhesus monkeys (Macaca mulatta).

The greeting behavior of rhesus monkeys (Macaca mulatta) was evaluated in a pharmacological test. It was observed in pairs of juvenile subjects reunited after a separation of two days. The observational measures were the duration of greeting behavior (social grooming, social play, and huddling) and the frequency of presentations, mounts and solicitations. d-Amphetamine (0.2 and 0.1 mg X kg-1) was found to shorten the duration of greeting behavior and increase the frequency of presentations and mounts. Diazepam (1 and 0.5 mg X kg-1) was found to prolong the duration of greeting behavior.

Animals↗
PubMed1983

Oxytocin-immunoreactive nerve fibers in the pars intermedia of the pituitary in the rabbit and hare.

The pars intermedia of the pituitary in the rabbit and hare is abundantly innervated by axons reacting selectively with antibodies against oxytocin. These axons contain dense secretory vesicles about 140 nm in diameter, i.e., smaller than those in the neurosecretory axons of the neural lobe. No fiber elements staining for other peptides (vasopressin, somatostatin, substance P) were observed in the pars intermedia, except rare leu-enkephalin axons restricted to the rostral zone of the gland. Dopaminergic innervation appears to be completely absent from the intermediate lobe. This was shown by the lack of reaction with an antibody against tyrosine-hydroxylase, which did reveal a well-developed tubero-infundibular system of nerve fibers. Axons reacting with an antibody against serotonin were irregularly distributed in the pars intermedia. In the absence of dopaminergic axons, the extensive oxytocin-like innervation may play a major role in regulating the melanotrophic cell activity in the Leporidae.

Animals↗
PubMed1983

Granular cell tumor of the stomach: a case report and review of the literature.

A case of granular cell tumor of the stomach in a 39-yr-old black female with peptic ulcer symptoms is presented. This lesion, a soft tissue tumor of disputed origin, has been reported in the stomach only 17 times before. In each case, the tumor was benign. Most of the patients were black, middle aged, and manifested symptoms of peptic ulcer disease. For this reason, we suggest that granular cell tumor be given serious consideration in the differential diagnosis should an upper gastrointestinal contrast study reveal a submucosal, benign mass lesion in a patient with these characteristics.

Adult↗
PubMed1982

Effects of experimental hypo- or hypernatremia on the fine structure of the pars intermedia of the murine pituitary. A morphometric study.

Quantified ultrastructural observations of the pars intermedia (PI) of the murine hypophysis enable evaluation and kinetic study of relatively fine secretory changes in the gland. Changes in volume of rER and newly formed dense secretory granules (Golgi granules) appear to best translate functional variations in the PI, as shown by the morphological effects of drugs affecting the dopaminergic control of the gland. Our morphometric results show that the PI is stimulated, but only briefly (no longer than 8-12 days), by both salt-loading and Na deprivation. However, the PI displays different secretory patterns in salt-loaded and Na-deprived mice; moreover, bromocriptine, which abolishes PI stimulation in Na-deprived mice, has only a slight inhibitory effect in salt-treated animals. Thus, it appears that the stimulation of the PI under both experimental conditions is triggered by different mechanisms. These results underline the plurifactorial control of the PI and show that the gland may have complex effects on hydromineral regulation.

Animals↗
PubMed1977

Effect of toloxatone on behaviour of primates.

1. The effects of (3-methyl)-3-phenyl-5-hydroxy-methyl-2-oxazolidinone (toloxatone) were studied on the behaviour of three species of primates: baboon, rhesus monkeys and chimpanzee. 2. The activity against reserpine-induced depression is observed in baboon as in rodents. 2. The administration of toloxatone induces three effects which probably have the same origin: suppression of feeding inhibition of the subordinate baboon, improvement of escape reaction in the conditioned chimpanzee, increase in general activity and the active component of social behaviour in grouped rhesus monkeys. These three effects can be interpreted as resulting from the stimulating effect of toloxatone, or more precisely from a disinhibiting effect. 4. Contrary to amphetamine, toloxatone does not induce, even at high or repeated doses, behavioural disturbances.

Administration, Oral↗
PubMed1976

Proximal tubular adenomas of kidney with so-called oncocytic features. A clinicopathologic study of 13 cases of a rarely reported neoplasm.

Four renal "oncocytomas" were observed between July 1974 and January 1975 at University Hospital. A review of all renal cell neoplasms previously classified as carcinomas since 1952 was conducted to determine whether this cluster of tumors represented a recent increase in incidence or whether other renal "oncocytomas" had gone unrecognized in the past. The 23-year review of 194 carcinomas yielded an additional nine "oncocytomas." None had appeared prior to 1964, whereas almost half were found in the 1973-1975 interval alone. While it appears that some "oncocytomas" of the kidney have gone unrecognized in the past, it is also evident that their recent increased incidence is epidemiologically significant. Renal "oncocytomas" and renal cell carcinomas are compared with respect to morphology, clinical presentation, and biologic behavior. Evidence derived from this comparison permits the conclusion that these neoplasms originate from proximal tubular epithelium, are benign clinicopathologic entities, and henceforth should be called proximal tubular adenomas with so-called "oncocytic" features.

Adenocarcinoma↗