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Biomedical subjects

R B Davis

Publications and source records attributed to R B Davis.

At least 145 records · Page 8Linked to original sources
PubMed1979

Effects of cervical dislocation on colony-forming cells in murine marrow cultures.

Bone marrow obtained in a conventional manner after killing mice by cervical dislocation demonstrates increased absolute numbers of GM-CFC when compared to that from living anesthetized mice. The anesthetic agent does not account for the observed difference. Interpretation of all studies of murine marrow culture must take this observation into account, and extrapolation of the results of such studies to living human marrow should be made with care. Further studies of the mechanisms by which cervical dislocation increases the numbers of GM-CFC may help to elucidate certain mechanisms of commitment of the pluripotential hemopoietic stem cell.

Animals↗
PubMed1978

Characteristics of statistical parameters used to interpret least-squares results.

This paper discusses properties of several statistical parameters that are useful in judging the quality of least-squares fits of experimental data and in interpreting least-squares results. The presentation includes simplified equations that emphasize similarities and dissimilarities among the standard error of estimate, the standard deviations of slopes and intercepts, the correlation coefficient, and the degree of correlation between the least-squares slope and intercept. The equations are used to illustrate dependencies of these parameters upon experimentally controlled variables such as the number of data points and the range and average value of the independent variable. Results are interpreted in terms of which parameters are most useful for different kinds of applications. The paper also includes a discussion of joint confidence intervals that should be used when slopes and intercepts are highly correlated and presents equations that can be used to judge the degree of correlation between these coefficients and to compute the elliptical joint confidence intervals. The parabolic confidence intervals for calibration cures are also discussed briefly.

Chemistry, Clinical↗
PubMed1977

Infectious coryza: cross-protection studies, using seven strains of Haemophilus gallinarum.

Bacterins prepared from 7 strains of Haemophilus gallinarum were used to immunized chickens for cross-protection studies. Three distinct immunotypes were distinguished. Slight protection between immunotypes was evident for some strains. Airsacculitis could be prevented by use of these bacterins; however, prevention was related to immunotype specificity. Hyaluronic acid found in 2 strains rendered them inagglutinable in homologous antiserums. Treatment with hyaluronidase rendered them agglutinable.

Agglutination Tests↗
PubMed1977

Infectious coryza: in vivo growth of Haemophilus gallinarum as a determinant for cross protection.

Four strains of Haemophilus gallinarum representing 3 immunotypes were used in exposure and challenge exposure studies to determine if in vivo growth of the organism would induce cross protection in chickens. Birds which recovered from infection to 1 immunotype were refractory to reinfection with the heterologous immunotype. In contrast, in vitro-produced bacterins produced immunotype-specific protection.

Animals↗
PubMed1976

Comparison of a microneutralization test in cell culture and virus neutralization test in embryonated eggs for determining infectious bronchitis virus antibodies.

A microneutralization test (MNT) system utilizing cytopathic effect end points was effective in determing neutralization indexes for infectious bronchitis virus antibodies. The system is reproducible within 1 index unit at the 95% level of probability. Comparison of the MNT to tests in eggs resulted in a positive correlation (B =0.81), which was significant (P greater than 0.01). The quantitative dose-response relationship of the MNT is linear (P greater than 0.005), with the 95% prediction limits fitting between one 10-fold dilution.

Analysis of Variance↗
PubMed1976

Multiple-drug chemotherapy in the management of acute lymphocytic leukemia during pregnancy.

Acute leukemia associates with pregnancy is relatively uncommon, and because of the age distribution of patients with acute leukemia the majority have had acute granulocytic leukemia. Various combinations of chemotherapeutic agents are commonly employed now to obtain maximal benefit, related to differing pharmacologic activities of single agents. The present case documents the use of multiple cytotoxic drugs in the management of acute lymphocytic leukemia, with successful delivery of a normal infant. In this patient severe anemia and potentially teratogenic drugs did not appear to affect the fetus.

Adolescent↗
PubMed1976

Efficacy studies on Haemophilus gallinarum bacterin preparations.

Broth cultures inactivated and potentiated by selected methods were tested in chickens for efficacy against homologous and heterologous challenge inoculation, using 2 serotype A strains of Haemophilus gallinarum. Although the 2 strains were within the same serotype, they failed to cross protect. One dose of thimerosal-inactivated bacterin was protective against homologous challenge, but 2 doses of formalin-inactivated bacterin were required. A bivalent bacterin protected chickens well against 1 strain, but not the other, at the 1-dose level.

Animals↗