Search PubMed⌕ Search

Biomedical subjects

S Hurwitz

Publications and source records attributed to S Hurwitz.

At least 181 records · Page 10Linked to original sources
PubMed1983

The amino acid requirements of growing turkeys. 2. Experimental validation of model-calculated requirements for sulfur amino acids and lysine.

The response to protein and the requirements for sulfur amino acids and lysine have been evaluated in male turkeys throughout the growth period as an experimental validation of model-calculated requirements (Hurwitz et al., 1983). The sulfur amino acid requirements were 3.4 and 3.1 mg/kcal for 1- and 5-week-old turkeys, respectively. The requirements for lysine were 4.8, 2.7, and 2.2 mg/kcal for 1-, 12-, and 16-week-old turkeys, respectively, which were in close agreement with the model predictions. Dietary protein in diets calculated on the basis of the model was sufficient to maintain maximal growth and feed efficiency. The results were the basis for accepting the general validity of the model-calculated requirements (Hurwitz et al., 1983).

Aging↗
PubMed1983

Congenital nevocellular nevus: a review of the treatment controversy and a report of 46 cases.

Because congenital nevocellular nevi can be distinguished clinically and histologically from acquired nevi, and because of their apparent increased potential for malignant degeneration, we favor complete one-stage excision of these nevi, regardless of the size of the lesion or the age of the patient, at the earliest opportunity, whenever such surgery is feasible and practical. If there is a question about the clinical diagnosis, a cutaneous punch biopsy can help determine the true nature of the lesion. Significantly, Walton et al. and Rhodes and coworkers found discrepancies in the literature concerning the level of nevus cells in neonates. They concluded that until these differences are reconciled, nevus cells in the deep reticular dermal collagen may be a sufficient, but not a necessary criterion for the diagnosis of congenital melanocytic nevus. We currently favor complete one-stage excision of congenital nevocellular nevi and feel that treatment by tangential excision or dermabrasion require further study. Finally, we present this paper as "advice" not only to the three authors who, in a recent issue of the British Journal of Plastic Surgery, requested it, but also to all clinicians. Hopefully, with time and further study, better criteria will be determined and a more definitive approach to this problem will be established.

Adolescent↗
PubMed1982

Attitudes toward clinical trials among patients and the public.

Attitudes toward clinical research, the focus of recent and damaging media attention, were assessed through questionnaires completed anonymously by 104 patients with cancer, 84 cardiology patients, and 107 members of the general public. Responses differed neither by subgroup nor by demographic variables. Data are therefore reported on the total population of 295 subjects. Most respondents (71%) believed that patients should serve as research subjects. In support of this belief, the majority cited potential benefit ot others and the opportunity to increase scientific knowledge, but a different bias emerged when they were asked about their own potential participation. This study shows that diverse respondents view clinical trials as important, ethical, and as a means of attaining superior clinical care. Major importance is attributed to making contributions to medical knowledge and to helping future patients. Contrasts are noted in patients' views of their own treatments v treatments of "'hypothetical others."

Adult↗
PubMed1982

Glucose homeostasis in the chicken.

Plasma glucose level and glucose turnover rate were studied in chicks (Gallus domesticus) fed isocaloric diets containing glucose, fructose or soybean oil as the main energy supplement. Plasma glucose level and body weight gain were not affected by glucose intake. Glucose turnover rate decreased from 15.6 to 10.2 mg/(min . kg) in chicks fed glucose- or carbohydrate-free diets, respectively, showing a limited dependence on glucose intake. Glucose conversion to lactate in the intestinal wall in vivo was studied by the introduction of radioactive glucose into a duodenal loop and fractionation of the labeled metabolites in plasma of the duodenal vein and peripheral blood. Up to 37% of the glucose was converted to lactate by the intestinal wall during absorption. Thus, by quenching the perturbations resulting from ingestion and absorption of glucose, the intestine assumes an important role in glucose homeostasis.

Animals↗
PubMed1982

Tocopherol absorption and metabolism in the chick and turkey.

Chickens and turkeys were fed from hatching basal diets to which tocopherol was added at levels of 10, 50 and 250 mg/kg for 28 days. During the last 4 days [3H]tocopherol and 141Ce were included in the diets. Plasma and liver tocopherol levels were correlated with dietary tocopherol in both chickens and turkeys, but concentrations were 1.5- to 4.5-fold lower in turkeys. Disappearance (absorption + catabolism) of tocopherol between feed and lower ileum was 78-90% of the ingested vitamin, and, no significant differences were found with dietary intake or between chickens and turkeys. Of the 3H-labeled material found in the duodenum, 24-40% was not extractable by organic solvents and comprised mainly tocopheryl glucuronides. The duodenal secretion of glucuronides increased with dietary tocopherol intake, and less than 30% of the secreted glucuronides were reabsorbed by the small intestine. The duodenal organic solvent-extractable 3H-contained 30-40% material that appeared to be tocopheryl quinone. This proportion increased with distance from the pylorus. Turkeys excreted 2.5- to 7-fold more glucuronides than chickens. This explains in part the lower plasma and tissue concentrations of tocopherol observed in turkeys.

Animals↗
PubMed1982

Cholecalciferol requirements of young turkeys under normal conditions and during recovery from rickets.

Day-old turkeys fed vitamin D-deficient diets became rachitic within 17-24 days. The symptoms included reductions in body weight, plasma calcium and inorganic phosphorus, plasma and intestinal calcium-binding protein (CaBP), plasma 25-hydroxycholecalciferol [25(OH)D3], bone ash, and kidney 25(OH)D3-24-hydroxylase and a rise in kidney 25(OH)D3-1-hydroxylase activity. Supplementation of the diet with 12.5 micrograms cholecalciferol per kilogram was sufficient to promote maximal body weight and normal plasma calcium, Plasma calcium, plasma phosphorus and bone ash. Feeding diets containing 250 or 1250 micrograms cholecalciferol per kilogram resulted in a reduced body weight. An increased in the concentration of plasma 25(OH)D3 with increasing dietary cholecalciferol concentration was observed. Feeding vitamin D-deficient rachitic birds for 4 days a diet containing 50 micrograms cholecalciferol per kilogram restored plasma calcium and phosphorus and bone ash. Body weight remained lower than that of the control for an additional 6-day period. Additional cholecalciferol, 25(OH)D3 or 1 alpha-hydroxycholecalciferol in the diet, intramuscular injection of the vitamin D derivatives, or a high-calcium, high-phosphorus diet did not accelerate the recovery from the rachitic state.

Animals↗
PubMed1982

The endoscopic diagnosis of gastric calcification.

The endoscopic diagnosis of gastric calcification has not been previously reported. We describe the endoscopic and histologic features of gastric calcification in a patient with diffuse interstitial pulmonary calcification of unknown etiology. It is suggested that this investigation may provide a convenient additional method of diagnosis, in a patient with suspected metastatic calcification.

Calcinosis↗
PubMed1982

Atopic dermatitis.

Explore the source record for details and available documents.

Administration, Topical↗
PubMed1981

"Pure" cutaneous histiocytosis-X.

The case histories of two young children who experienced skin rashes involving various areas of the body are reported. The diagnosis of pure cutaneous histiocytosis-X was established after extensive studies revealed no other organ involvement. The patients were treated with oral corticosteroids. Currently, both children are in good health, show no evidence of disease, and have been followed over a four-to-five-year period. Therapy with corticosteroids may not be indicated with pure cutaneous histiocytosis-X unless there is evidence of extracutaneous dissemination or rapid progression of the disease.

Adrenal Cortex Hormones↗
PubMed1981

Amoebiasis in an urban black population.

Amoebiasis is a common cause of dysentery and liver abscess at Baragwanath Hospital, Johannesburg. Forty-eight adult patients with amoebiasis were diagnosed during the 8-month period 1 December 1979 to 31 July 1980. There was a high incidence of extra-intestinal complications (38%) and a high mortality rate (12.5%) in this series. The importance of early surgery in fulminating dysentery which has not responded to amoebicidal therapy is emphasized. The need for early diagnosis is crucial, since failure to consider the possibility of the presence of amoebiasis may result in serious complications. This study demonstrates that endemic 'pockets' of amoebiasis are probably present in Soweto, Johannesburg. It is suggested that those involved in the preparation or handling of food for public consumption be clinically examined, and their stools examined for cysts of Entamoeba histolytica.

Amebiasis↗
PubMed1981

Relationships between cholecalciferol metabolism and growth in chicks as modified by age, breed and diet.

Fast-growing heavy (White Rock) chicks, fed a vitamin D-deficient diet, exhibited a higher activity of kidney 25-hydroxycholecalciferol-1-hydroxylase (1-hydroxylase) than slow-growing light (White Leghorn x Rhode Island Red) chicks fed the same diet. 1-Hydroxylase and duodenal calcium-binding protein (CaBP) declined with age. Feeding of low energy diets with or without vitamin D resulted in a slower rate of growth and reduced 1-hydroxylase activity and CaBP concentration. Severe dietary restriction of either calcium or phosphorus resulted in a lower growth rate as well as a duodenal CaBP as compared to a moderate mineral restriction. The severe dietary calcium restriction also resulted in a lower 1-hydroxylase activity than that resulting from a moderate restriction. The results clearly indicate that high 1-hydroxylase activity and a high intestinal CaBP are associated with a high growth rate.

25-Hydroxyvitamin D3 1-alpha-Hydroxylase↗
PubMed1981

Availability of phosphorus contained in poultry litter for lambs.

Percentage net phosphorus availability (NPHA) and set phosphorus utilization (NPHU) of the phosphorus contained in a heat-sterilized poultry litter (PL) as compared to feed grade dicalcium phosphate (DCP) for lambs was assessed by the "slope" method. The method was based on the evaluation of the function of apparent phosphorus absorption (NPHA), or retention (NPHU), on phosphorus intake. Nitrogen retention was also evaluated. Plasma inorganic phosphorus concentration as a function of phosphorus intake was evaluated and compared to NPHA and NPHU. The percentage of NPHA was found to be 63.7 and 39, and that of NPHU was 63 and 38 for the phosphorus supplied by DCP and PL, respectively. Thus, the NPHA or NPHU for the phosphorus contained in PL is 60.9 and 60.3% of that of DCP, respectively. The slope ratio between the two phosphate supplements as observed for plasma inorganic phosphorus concentrations was similar to those found for NPHA and NPHU but the coefficient of variation was 5 times higher. Nitrogen digestibility was not affected by the level of phosphorus in the diets. Correlation between nitrogen retention and NPHA or NPHU was, however, significant (P less than 0.05). The slopes of dependence of N retention upon phosphorus intake were 2.81 and 1.6 (P less than 0.05) for DCP and PL treatments, respectively, and the ratio between the slopes was 0.57, close to the ratio of NPHU in PL to DCP-supplemented diets.

Animal Feed↗
PubMed1981

Client preference-treatment congruence as a facilitator of length of stay: supporting an old truism.

Client-program congruence is studied for its association with clients' lengths-of-stay in community-based drug abuse treatment programs. Congruence, defined as the fit between clients' preferences for treatment program types and actual program placements, is highly associated with extended client lengths-of-stay in treatment. The results are discussed in terms of person-environment fit and attribution theory regarding perceived control, achievement, and success. Finally, discussion focuses on the use of the results to bring about changes in policy regarding the operation of the local community's system of services.

Adolescent↗
PubMed1980

Observations of the use of 1 alpha hydroxycholecalciferol in the prevention of bovine parturient paresis.

Varying doses of 1 alpha-hydroxycholecalciferol (1 alpha-HCC) (50, 150, 250 and 350 micrograms) in propylene glycol were injected intramuscularly into 30 dry adult Israeli Friesian cows. Fourteen of these animals received a second dose; four were given 250 or 350 micrograms 48 hours after the first dose and 10 were given 350 micrograms 72 hours after the first dose. Plasma calcium rose after 24 hours at all dose levels except 50 micrograms. A dose-dependent peak in plasma calcium was reached after three to four days, followed by a return to baseline five days (150 micrograms) and eight days (250 and 350 micrograms) post injection respectively. Repeating the injection 48 or 72 hours later increased the time span by three and four days respectively. The effect of plasma inorganic phosphate was double that on plasma calcium. Plasma magnesium declined slightly three days post injection. High calcium feeding in conjunction with one or two injections of 350 micrograms 1 alpha-HCC did not modify the response of plasma calcium. An injection of 350 micrograms of 1 alpha-HCC was given once to 40 parturient paresis-prone cows of the same breed and twice at 72-hour intervals to 37 such cows. Six of the animals received 5 mg of flumethasone together with the second injection and 13 received it 48 hours later. This was to induce parturition, which occurred within 24 to 48 hours. None of the cows injected earlier than 24 hours prepartum developed parturient paresis in comparison with 22 out of 60 control animals which did. The results suggest that 1 alpha-HCC is useful in the prevention of bovine parturient paresis.

Animals↗