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Biomedical subjects

R Robinson

Publications and source records attributed to R Robinson.

At least 199 records · Page 11Linked to original sources
PubMed1988

Homologous recombination between human immunodeficiency viral DNAs in cultured human cells: analysis of the factors influencing recombination.

Recombination between HIV DNAs was analyzed using DNA transfection in cell cultures and the optimal conditions for efficient recombination were determined. Recombinant plasmid DNA substrates were constructed from HIV proviral DNAs and the success of recombination was measured by the production of viable hybrid virus. The process of recombination between HIV DNAs was shown to be i) dependent on homology between the truncated HIV DNAs and ii) maximum with concentrations of the truncated DNAs 3ug and above. HIV isolates with heterogeneity in their primary sequence, thus offer an ideal system for the analysis of the requirement of homologous recombination. In addition, recombination methodology would be useful for generating hybrid HIVs for the analysis of specific viral gene functions.

Calcium Phosphates↗
PubMed1988

Linkage studies of wavy in the Norway rat, Rattus norvegicus.

The gene for wavy coat (wv) is shown to assort independently of the albino (c), brown (b), hooded pattern (h) and pink-eyed dilution (p) genes. The c and p genes, known to be in linkage group I, were observed to show a recombination value of 19.9 +/- 3.3 per cent.

Animals↗
PubMed1988

Inheritance of colour and coat in the Belgian Shepherd dog.

The several colours and coats of the Belgian Shepherd dog are shown to be due primary to combinations of the following genes: dominant black (As), dominant yellow (Ay), chinchilla (ch), long hair (l) and wire hair (Wh). The gene for black and tan (at) is or has been present in the breed. All of the dominant yellow dogs exhibit a black facial mask and extensive suffusion of black guard hairs on the body.

Animals↗
PubMed1988

A primer on how to analyze contracts and avoid the traps.

Contracts from preferred provider organizations, health maintenance organizations, independent practice associations, and managed health plans present numerous problems for primary care physicians. The ability to understand the terms and conditions is an essential part of the practice of medicine today. Additionally, physicians need to involve experts in the preparation of counterproposals that will render contracts fair and equitable for physicians. The blind acceptance of a contract may dramatically increase a physician's liability exposure. Although contracts have become a permanent fixture in the current health care delivery environment, physicians can formulate informed and intelligent responses. They and their office personnel can learn basic analysis techniques of such documents that will aid in surviving the onslaught of contracts.

Contract Services↗
PubMed1988

The emerging role of the medical staff professional.

In today's hospital environment, a new group that may be termed "medical staff professionals" provides administrative and managerial support for both the clinical and non-clinical activities of today's medical staff. This article explains why hospitals and medical staffs recognize the need for such professionals, and discusses the areas that such individuals must understand in their expanding role within the hospital. Such areas include: competing hospital/medical staff interests, the medical staff's need for access to independent counsel, the role of the medical director, the importance of medical staff bylaws, and the relationship of medical staff professionals to quality assurance activities.

Career Choice↗
PubMed1988

Managed care contracts. A primer on how to analyze contracts and avoid the traps: Part 2.

Because many business entities are attempting to increase their control over medical practice, physicians must take extreme care in reading proposed amendments to managed care contracts. Beware of vague language concerning utilization review; contracts that require you to passively accept future contract modifications; innocuous language that may endow the medical director with excessive authority; and unacceptable regulations concerning medical, financial, and administrative records. The author suggests counterproposals that are fair to both business entities and participating physicians. He further recommends maintaining an ongoing discussion between both parties in order to further chances for success.

Contract Services↗
PubMed1987

Genetic linkage in the Norway rat.

The present status of research on genetic linkage is reviewed. Where possible, the data are statistically combined to give consolidated estimates of the recombination value. Ten groups of linked genes have been determined. The first assignments of linkage groups to specific chromosomes have been facilitated by inter-species cell hybridisation.

Animals↗
PubMed1987

Infertile or childless by choice? A multipractice survey of women aged 35 and 50.

Eleven general practitioners examined the medical records of all women on their lists born in 1950 (617 patients) and 1935 (533 patients) to determine the prevalence of childlessness and specialist consultations about infertility. Eighty eight (14.3%) of the women born in 1950 and 41 (7.7%) of those born in 1935 were childless. Sixty eight women born in 1950 (11.0%) and 17 born in 1935 (3.2%) were considered childless by choice. Involuntary childlessness was found in 20 (3.3%) of the women born in 1950 and 24 (4.5%) born in 1935. Forty two (6.8%) of the women born in 1950 had consulted a specialist about infertility as compared with 19 (3.6%) born in 1935. This study found a significant increase in voluntary childlessness among the younger women; there was no evidence of a change in the prevalence of involuntary childlessness despite the increasing demand for specialist referral, which appeared to be made by women who were parous or destined to become so.

Adult↗
PubMed1987

Features of a seminal proteinase inhibitor- zona pellucida-binding component on murine spermatozoa.

Murine cauda epididymal sperm contain sites on the plasma membrane over the apical portion of the acrosome that recognize proteinase inhibitors and the homologous zona pellucida. Ten times more of the component can be extracted from cauda and ductus sperm than from equal numbers of caput and corpus sperm. Likewise, few sperm from the upper epididymal regions are able to bind seminal inhibitor, while the majority of sperm from the cauda and ductus do bind. Cauda epididymal and ductus sperm lose little of their ability to bind inhibitor after a 4-hour in vitro incubation in either a capacitating or a noncapacitating medium. The percentage of naturally inseminated sperm with the seminal inhibitor bound to their surface decreases to about 10 after 4 hours in utero. Approximately 80% of these sperm show positive fluorescence when given the opportunity to rebind the the inhibitor, and these sperm do have an intact plasma membrane over the apical portion of the acrosome. Furthermore, after 4 hours in utero, the inhibitor bound in the same region of the sperm head as it did on freshly ejaculated sperm. The seminal inhibitor inhibits the binding of sperm to the zona if added during the first 15 minutes of incubation but has no effect on attachment. The data indicate that sperm gain the ability to bind the seminal inhibitor during the epididymal sojourn. Furthermore, this binding capacity is not lost during in vitro or in utero incubation. The site is not involved in sperm-zona attachment but does participate in the binding of sperm to the zona.

Acrosome↗
PubMed1986

Preparation and characterization of monoclonal antibodies to pregnenolone 16-alpha-carbonitrile inducible rat liver cytochrome P-450.

Hybridomas were prepared from mouse myeloma cells and spleen cells derived from BALB/c female mice immunized with purified rat hepatic pregnenolone 16-alpha-carbonitrile (PCN) induced cytochrome P-450 2a/PCN-E. The monoclonal antibodies (MAbs) thus obtained were screened for binding to the purified P-450 2a/PCN-E by radioimmunoassay. Eleven independent hybrid clones produced MAbs, each of which was of a single mouse immunoglobulin subclass of the IgG1, IgG2a or IgG2b type. Each of the MAbs produced by the eleven individual hybrid clones bound strongly to P-450 2a/PCN-E as assessed by radioimmunoassay and immunoprecipitation of P-450 2a/PCN-E in Ouchterlony double-immunodiffusion plates. Of the eleven MAbs, three also bound strongly to the phenobarbital-inducible rat liver cytochrome P-450 PB-4. Thus, two classes of MAbs were obtained, one class specific for P-450 2a/PCN-E and a second class that bound to both PCN- and phenobarbital-inducible P-450 forms. The reactivities of one MAb from each class toward eight highly purified rat hepatic cytochromes P-450 were examined using solid phase enzyme-linked immunosorbent analyses. The MAb designated C2 was found to be specific for P-450 2a/PCN-E and did not cross-react with seven other P-450 forms. This MAb was shown to be an effective probe for monitoring, by Western blotting, the induction of microsomal P-450 2a/PCN-E by PCN and phenobarbital. The MAb designated C1 reacted both with P-450 2a/PCN-E and with the two major phenobarbital-inducible P-450 forms, PB-4 and PB-5. None of the MAbs was inhibitory towards P-450 2a/PCN-E-dependent aryl hydrocarbon hydroxylase, benzphetamine N-demethylase, ethoxycoumarin O-deethylase or ethymorphine N-demethylase activity, indicating that the epitopes recognized by these MAbs are not directly associated with catalytic activity. The strong reactivities of three of the MAbs with both P-450 2a/PCN-E and P-450s PB-4 and PB-5 indicate that these two structurally quite different cytochrome P-450 families share at least one common epitope. These new MAbs are additions to our library of MAbs to different cytochromes P-450 and should help further our understanding of the relationship of cytochrome P-450 phenotype and multiplicity to inter-individual differences in drug and carcinogen metabolism and sensitivity.

7-Alkoxycoumarin O-Dealkylase↗
PubMed1986

Restructuring the welfare state: an analysis of public expenditure, 1970/80-1984/85.

Since the election of the Thatcher Government in 1979, public expenditure on the welfare state has undergone a series of changes. The nature of change has, however, often been obscured by the use of inadequate and misleading statistical data. This paper presents a systematic examination of public expenditure on education, health care, housing and social security over the period 1979/80 to 1984/85. It shows that, contrary to much political rhetoric, the major changes in the welfare state have not always arisen from reductions in programme expenditures, but from changes in the composition of expenditure. It is the latter that has often increased economic inequality and can be legitimately referred to as 'restructuring'.

Government↗
PubMed1985

Competition between seminal and exogenous proteinase inhibitors for sites on murine epididymal sperm.

Sixteen proteinase inhibitors were tested for their ability to compete with the natural seminal inhibitor for binding to the surface of murine epididymal sperm. The most effective competitors, 4-methylumbelliferyl-p-quanidinobenzoate (MUGB) and p-nitrophenyl-p-guanidinobenzoate (NPGB), are also effective inhibitors of both murine acrosin and in vitro fertilization of mouse gametes. The data support the suggestion that the inhibition of fertilization by these inhibitors may be effected by their action on the sperm surface rather than binding to enzymes located within the acrosome. Since the surface acceptor molecule recognizes a number of inhibitor types, as well as substrates for such enzymes as trypsin and acrosin, the acceptor's binding site may be similar to the active site on the enzyme.

Animals↗
PubMed1985

Development and characterization of a human ovarian cancer cell line which clones without agar in vitro.

A new human ovarian cancer cell line has been initiated which clones without agar in vitro. The cell line has been characterized by growth of a tumor resembling the primary tumor in a nude mouse, by human lactic dehydrogenase isozyme pattern, by human karyotype, and by lack of contamination by other cell lines. Initial studies have demonstrated the presence of epidermal growth factor receptors in this cell line. The utility of this line for clonogenic studies is demonstrated by dose-response studies with doxorubicin, cisplatinum, and 13-cis-retinoic acid.

Agar↗