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Biomedical subjects

B Stein

Publications and source records attributed to B Stein.

At least 181 records · Page 10Linked to original sources
PubMed1986

Carcinoembryonic antigen levels in colonic lesions.

We evaluated the likelihood of tissues to be positive for carcinoembryonic antigen and the intensity of carcinoembryonic antigen staining in specimens of villous adenomas, mixed polypoid villous adenomas, polypoid adenomas, and diverticulitis using the peroxidase-antiperoxidase technique. The presence of carcinoembryonic antigen could be demonstrated in all of the specimens; however, the intensity of staining varied. Villous adenomas were the most intensely stained, followed by mixed polypoid villous adenomas, polypoid adenomas, and diverticulitis. We conclude that (1) the intensity of tissue levels of carcinoembryonic antigen parallels the malignant potential of these different groups of lesions, (2) carcinoembryonic antigen intensity of mixed polypoid villous adenomas is more similar to villous adenomas than polypoid adenomas, and (3) the presence of carcinoembryonic antigen in diverticulitis is not a result of dysplasia.

Adenoma↗
PubMed1986

A study of disturbed and non disturbed adolescents: the Toronto Adolescent Longitudinal Study. I.

The Toronto Adolescent Longitudinal Study was undertaken to examine personality development in a non-clinical sample of children from ages 10 through 19. Fifty-nine boys and girls, selected to represent the full range of behavior presentation in regular classrooms, have participated throughout the complete study. Each year the students and at least one parent participated in a full day evaluation during which a comprehensive battery of measures was administered to assess their psychosocial characteristics. Some exemplary results are presented regarding the personality functioning and associated characteristics of the group at age 13. Our results lead us to conclude that adolescence should not be considered as a homogeneous developmental stage. Young adolescents can be differentiated along a dimension of competence in personality functioning which is associated with differences in their clinical presentation, self concept and behavior patterns.

Adolescent↗
PubMed1984

PO2 and pH measurements within the rabbit oviduct following tubal microsurgery: reanastomosis of previously dissected tubes.

Adhesions of the fallopian tube might be a source of generalized infertility. In order to improve the mechanical and functional properties of the oviduct, microsurgical replacement of the affected tubular segments have been applied, however, with contradictory results. In order to improve the situation and gain further information about this problem, catheter microelectrodes for Po2 and pH measurements within the lumen of the fallopian tube have been developed. The validity of the measurements was tested in a series of rabbits (Dutch belt strain, n = 19, 3.5-4.5 kg bw) which have been laparatomized under pentobarbital anesthesia during the oestrus phase. From one side of the oviduct 1 cm was resected and the free ends reanastomosed while the other side served as a control. Six to eight weeks later Po2 and pH values within the oviduct were measured. After another 4-5 weeks ovulation had been induced and artificial insemination performed. 64 hours later the rabbits were sacrificed. The oviducts were isolated and the corpora lutea as well as the ova were collected and examined histologically. The mean Po2 of the oviduct was 53 (+/- 16) mm Hg (mean +/- SD) for the control side and 56 (+/- 13) mm Hg (mean +/- SD) within the anastomosed tubes. The range of values was the same in both groups (n = 8) 34-75 mm Hg. A T-test comparison of the means of the two groups gave p-values which were not significant (p greater than 0.1). Po2 fluctuations with small-fast amplitudes (1 mm Hg) and additional slow-large oscillations (about 20 mm Hg) have been observed similar to the Po2 waves described for muscle and brain. The mean pH value of the oviduct a showed slight, statistically significant pH differences (7.75 reanastomosed side, 7.94 control side) whereby the degree of adhesions was correlated with luminal pH value. In three rabbits the relationship between corpora lutea and fertilized ova was 1:6, 2:9, 3:6 for the reanastomosed side while the control side showed balanced quotients of 4:4, 4:4, 6:6. In two rabbits unfertilized ova have been observed within the reanastomosed tubes where the typical outside layer of mucoproteids was absent while the control side was normal. Nevertheless, within both oviducts a continuous layer of epithelial cells has been observed even after reanastomosis.

Animals↗
PubMed1984

Occlusive vascular disease associated with cerebral arteriovenous malformations.

Selective carotid angiography and computed tomography were used in a study of the association of occlusive vascular disease with cerebral arteriovenous malformations in 13 patients. The arterial occlusions ranged from focal stenosis in the major artery supplying the malformation to complete occlusion of the supraclinoid internal carotid artery with subsequent development of "moyamoya" collaterals. The majority of the arterial occlusions were proximal to the vascular malformation. Some, however, extended distal to the major branch supplying the arteriovenous malformation (AVM). Selective angiography with subtraction techniques defines the distinct angioarchitecture of these AVMs and the associated stenoses and collateral telangiectases.

Adult↗
PubMed1980

Retroperitoneal neurofibromatosis and venous anomalies.

A 45-year-old woman had abdominal pain, azotemia, and hypertension. Intravenous pyelography revealed bilateral ureteral compression by extrinsic tumor masses that proved to be neurofibromata by histologic examination. After surgical removal of the tumors, she became normotensive and asymptomatic. In addition, severe medial hypertrophy of veins was seen in the tissue examined. We believe that the latter is most probably related to the neurofibromatosis and is analogous to the hypertrophic arterial changes known to occur in patients with von Recklinghausen's disease.

Female↗
PubMed1978

Removal of an arteriovenous malformation from the basal ganglion.

A case is reported in which an arteriovenous malformation was removed from a portion of the basal ganglion and region of the lenticulostriate arteries. The patient made an excellent recovery. The importance of stereoangiography and the operating microscope are emphasised.

Adult↗
PubMed1978

An "oncometer" of clinical measurement of colloid osmotic pressure of plasma.

Measurement of colloid osmotic pressure complements measurements of pulmonary artery wedge pressure for assessing the risks of pulmonary edema and constitutes an increasingly important reference for purposes of guiding selection of colloid or crystalloid fluids in patients with acute cardiac disease. We describe a simple device for its routine clinical measurement. A membrane, selectively impermeable to molecules of relative molecular mass (Mr) greater than 30000, is rigidly mounted between a sample chamber and a reference chamber filled with isotonic saline. A pressure transducer measures the negative pressure developed in the reference chamber and displays it on a digital panel meter. The sensor chamber accommodates samples of 50 to 300 microliter. Equilibration is completed within 2 min. A control solution of human serum albumin (50 g/liter) is measured to confirm the accuracy of calibration of the system, with reproducible readings of 25.9 g/cm2 within one SD (equivalent to 0.4 g/cm2). Technical simplicity of operation and modest costs of disposables have made feasible the routine measurement of colloid osmotic pressure.

Colloids↗
PubMed1976

Factors affecting human percutaneous penetration of methotrexate and its analogues in vitro.

Factors affecting the percutaneous penetration of methotrexate (MTX) and its analogues through excised human skin were studied. With application of 0.05% MTX solution to the epidermis, 0.07% of the applied dose was recovered in the epidermis and less than 0.005% penetrated completely through the skin. The percent of drug which penetrated remained constant from 0.05% to 2.0% MTX and was also unchanged by increasing incubation temperature from 28 degrees C to 37 degrees C. Cellophane tape stripping of stratum corneum following drug incubation removed essentially all the MTX that had been measured in whole epidermis. Binding of MTX was localized to the outermost layers of the stratum corneum. With removal of the stratum corneum prior to drug incubation, 25% of the applied MTX penetrated through the skin. Various vehicles were tested to determine their effect on MTX percutaneous absorption. Dimethylsulfoxide (80%), dimethylacetamide (25%), or retinoic acid (0.1%) had no effect on penetration. Maximum enhancement of penetration by 25-fold and 143-fold was obtained with retinoic acid (saturated solution in aqueous ethanol) and C-10-methylsulfoxide (2.5%), respectively. The penetration of lipid-soluble derivatives of MTX was also tested. The compound that penetrated best was the dimethyl ester of dichloro-MTX with a 3-fold increase in penetration over MTX.

Acetamides↗