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Biomedical subjects

J Keller

Publications and source records attributed to J Keller.

322 records · Page 18Linked to original sources

A computed tomography-radiation therapy treatment planning system utilizing a whole body CT scanner.

An external beam radiation therapy treatment planning system has been developed to run on the GE CT/T whole body scanner. The system interactively obtains treatment planning information directly from CT scans, including relative density conversion of user input inhomogeneity regions. The program generates beams isodose tables from input TAR-SAR data using the Cunningham model. Inhomogeneity corrections are applied using the power law TAR method at low energies and the TAR ratio method at high energies. Beam data are generated on the central axis and at off-axis locations coplanar with each CT scan, and isodose distributions are displayed on any transverse, coronal or sagittal plane. Examples of plans and initial verification results are discussed.

Computers↗

Business coalition initiatives related to behavioral healthcare purchasing and quality improvement.

Across America there are over 90 employer health coalitions, and their ranks are growing. Their members can be businesses located in a city, a region or a state, while a few encompass employers located in multistate regions. Coalitions may include only private-sector employers, or private- and public-sector employers; some are coalitions between employer purchasers and providers. Following a brief historical overview, this article summarizes the behavioral healthcare initiatives that are currently under way in six business coalitions.

Cost Savings↗

Computers in radiology. Interfacing with peripheral devices.

A fundamental part of building a computer system is control of and communication with peripheral devices. With use of graphics display terminals, video image digitizers, and array processors as examples, the basics of peripherals are discussed as they affect radiologic applications.

Computers↗

Attitudes of low-income parents toward seeking help with parenting: implications for practice.

Fifty-two low-income parents were surveyed to determine attitudes toward parenting and help seeking. Although a majority agreed that most parents, even "good" parents, need help or advice about parenting and thought they would seek help with parenting, low-income parents were less likely to believe in or seek out help than those with higher incomes. The most frequently selected sources of help were family, books and videos, telephone help-lines, and friends. The least likely sources of help were child protective services, school personnel, clergy, and social service/counseling agencies. Parent support and education groups were likely sources of support for only one in four low-income parents.

Adolescent↗

Morphological and immunocytochemical characteristics of human tumor cell lines for use in a disease-oriented anticancer drug screen.

A panel of 60 human tumor cell lines is currently being used in the U.S. National Cancer Institute's in vitro anticancer drug screen. The panel is organized into 7 subpanels; 6 leukemia/lymphoma lines comprise one subpanel, and 54 other lines are organized into subpanels representing solid tumors of the central nervous system (CNS), colon, lung, ovaries, kidneys and melanomas. In the present study, the leukemia and lymphoma cell lines were analyzed by flow cytometry for appropriate CD antigens; all but 1 line showed patterns of expression consistent with their reported derivations. The solid tumor lines were characterized individually using morphological and immunocytochemical techniques to determine their relative degrees of representativity for the subpanels within which they are currently grouped. Histological, histochemical and ultrastructural examinations were performed on cell lines grown under identical conventional culture conditions and as xenografts in nude mice. Immunocytochemistry using panels of antibodies raised against 6 types of intermediate filaments, 7 adenocarcinoma-associated antigens, 7 melanoma/neuro-ectodermal-associated antigens, 3 neuroendocrine-associated antigens, 9 urinary tract associated antigens, and 4 markers of muscle differentiation was done on cells grown in monolayer culture. Central nervous system (CNS) cell lines lacked expression of glial fibrillary acidic protein, but all had other features consistent with derivation from glioblastoma. Lines derived from adenocarcinomas of the colon, lung and ovary, for the most part, expressed adenocarcinoma-associated antigens and showed histological and/or ultrastructural evidence of gland formation and other adenomatous features. Most of these lines were poorly differentiated. Lines derived from large-cell and squamous-cell cancers also showed some characteristics consistent with their reported origins, except for one line which showed immunocytochemical and morphologic characteristics consistent with rhabdomyosarcoma. The 2 lines derived from small cell lung cancer (SCLC) lacked neurosecretory granules and 3 other SCLC markers but showed morphologic features consistent with SCLC. Most melanoma cell lines strongly expressed melanoma-associated antigens and were morphologically similar to human melanoma. Five lines produced premelanosomes, melanosomes or melanin. Most of the renal cancer cell lines showed morphologic or immunocytochemical features consistent with renal clear cell carcinoma. Collectively, these morphological and immunocytochemical analyses provide information concerning tissue of origin, tumor type, degree of differentiation and other biologic features essential to the use of these lines in a disease-oriented in vitro antitumor drug screen and to the interpretation of data derived therefrom.

Antibody Specificity↗

The effect of propylthiouracil (PTU) on heat production in chickens maintained on different levels of nutrition.

Using the method of forced feeding on higher and lower levels, two groups of chickens differring in growth rate were obtained. In the chickens of the two groups 72 measurements of heat production were made. Chickens of these groups were compared considering either the same age or similar body weight. It has been found that propythiouracil treatment (120 mg/kg duging 10 consecutive days) decreases heat production in the chickens of both groups. However, this effect was much more pronounced in the birds maintained on the higher level of nutrition and growing more rapidly than in those maintained on the lower level of nutrition and growing slowly.

Animal Nutritional Physiological Phenomena↗

Body weight and metabolic level in growing chickens.

Body weight and metabolic level in growing chickens. Acta Physiol. Pol., 1977, 28 (6): 575-583. In the investigations carried out on 128 White Rock chicken the metabolic level was determined under standard conditions in chickens characterising by different growth rate resulted from different feeding levels. It was shown that the feeding level of growing chicken has an essential influence on the character of the regression between the metabolic level and body weight. It was also found that this regression is not necessarily ot the character of Kleiber's function H = aWb. The differences in the metabolic level between the chickens maintained on different feeding levels did not disappear even after 4 days of starvation. In the light of the obtained results and recent investigations by other authors the usefulness of the so-called metabolic unit of the body size based on W0.75 in context to growing animals within one species has bee criticized.

Animal Feed↗

The NHLBI workshop on Hypertension in Hispanic Americans, Native Americans, and Asian/Pacific Islander Americans.

In June 1994, the National Heart, Lung, and Blood Institute held a workshop entitled "Epidemiology of Hypertension in Hispanic Americans, Native Americans, and Asian/Pacific Islander Americans." The studies that served as the basis for the workshop along with a summary of two workshop panel discussions are being published as a supplement by Public Health Reports. In this article, the authors present graphs that compare results across these studies with data for non-Hispanic whites, blacks, and Hispanics from the Third National Health and Nutrition Examination Survey. The graphs indicate differences in mean blood pressure levels within and among these three population groups; such differences are also apparent in comparisons of these groups with the U.S. white and black populations. Although they appear modest, these differences are sufficient to result in increased mortality rates in populations with higher levels of hypertension. Environmental influences appear to underlie most of these differences. In all of these populations, blood pressure control rates are poor. Based on these studies, hypertension prevention and control programs should be undertaken. Special emphasis should be placed on the underserved minority populations that were the focus of the workshop.

Adult↗