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911.
Summary Pi phenotypes have been determined by isoelectrofocusing in a sample of 538 healthy individuals from Southern Germany. Further subdivision of the common PiM phenotype is described. A procedure for the delineation of six common subtypes is presented. It is assumed that the six subtypes are determined by three alleles which are provisionally called PiMa, PiMb, and PiMc. Their frequencies in this sample were 0.75, 0.06, and 0.15, respectively.Supported in part by INSERM, contract No. AT-FA-58 相似文献
912.
The utility of various techniques for assessing dominance relations within captive primate groups has been repeatedly debated.
The present research compared status rankings derived from observations of spontaneous agonism with rankings based on success
in experimental competitions within two groups of captiveSaimiri. Observation of social agonism revealed stable dyadic dominance relations in both groups. Status rankings derived from the
competitive Water Dominance tests were neither temporally stable nor concordant with observational rankings. Thus the utility
of the Water Dominance test as an index of dominance among captive squirrel monkeys seems questionable. Results are discussed
in terms of ecological factors in group adaptation which lead to species-specific differences in the relationship between
social conflict and competition. 相似文献
913.
Henry R. Black Samuel O. Thier Philip F. Felig James F. Jekel Joseph Belsky James L. Bernene Everett Cooper Vincent A. De Luca Jr. Martin H. Floch Marvin Garrell Pasquale E. Perillie Robert L. Piscatelli George F. Thornton 《The Yale journal of biology and medicine》1977,50(6):637-644
In July, 1975, the Departments of Internal Medicine at the Yale University School of Medicine and eight community hospitals in southern and western Connecticut formed the Yale Affiliated Hospital Program (YAHP) in Internal Medicine. The YAHP provides a planned and focused program of continuing education for medical staff and housestaff at the affiliated hospitals. Six formats for the over 1,000 rounds, lectures, and conferences given annually are used. The members of the YAHP also cooperate in housestaff and faculty recruiting, evaluation of quality of care and evaluation of the process of continuing medical education itself. This report summarizes the organization, goals and future plans of the YAHP. 相似文献
914.
915.
The nature of a T-cell factor specific for poly(Tyr,Glu)-poly(Pro)-poly(Lys) [(T,G)-pro-L] was established in the present study. The activity of the (T,G)-Pro-L-specific factor was not removed by anti-mouse immunoglobulin Sepharose columns, suggesting that it is not a classical immunoglobulin. On the other hand, the factor lost its activity after passage through immunoadsorbents prepared with anti-H-2 sera raised against theH-2 haplotypes of the mouse strains in which the factor was prepared. Furthermore, this factor was adsorbed byI region-specific antisera but not by antisera directed against theI-J andI-C subregions as well as theK andD regions of theH-2 complex. Thus, the (T,G)-Pro-L-specific T-cell factor is most probably anI-A subregion gene product. 相似文献
916.
The primary humoral responses of mice to the linear random terpolymerl-Glu56-l-Lys35-l-Phe9 (GLø) were studied, utilizing the Farr antigen-binding technique and a new hemagglutination assay. This new hemagglutinin assay was easier and more convenient than the conventional Farr method, and was more sensitive in detecting early IgM responses. Following primary immunization, the majority of antibodies produced by responder strains were 2-ME-sensitive. These 2-ME-sensitive antibodies chromatographed at the same relative position as IgM on a Sepharose 6B column. On the other hand, no antibodies of either the IgM or IgG class could be detected in nonresponder strains. These data are consistent with the hypothesis that two complementingIr genes are required for the primary IgM response to GLø, in contrast to findings previously reported for (T,G)-A — L, anotherH-2-linked, complementing,Ir gene system. The implications of these differences are discussed. 相似文献
917.
Robert L. Stolfi Leslie M. Stolfi Ruth A. Fugmann Daniel S. Martin 《Cancer immunology, immunotherapy : CII》1977,3(2):137-143
Summary Because it had been reported that splenectomy produces a tumor-inhibitory effect in several transplantable tumor systems when the surgery is performed before tumor challenge, we attempted to examine this putative immunological manipulation in a therapeutic situation.A spontaneous, autochthonous, murine breast tumor system was utilized in the present studies, and treatment was initiated in animals bearing large tumors (averaging 0.5 g). To amplify any immunological benefit ensuing from splenectomy, the tumor burden in the host was reduced by ancillary treatment with enucleative tumor surgery or with enucleative tumor surgery plus cytoreductive combination chemotherapy.Splenectomy performed in conjunction with enucleative tumor surgery was associated with an increment of cure in each of four separate experiments in comparison to treatment with enucleative tumor surgery alone. In four of five experiments utilizing different combinations or schedules of chemotherapeutic agents following enucleative tumor surgery, the addition of splenectomy resulted in a decrease in the rate of tumor recurrence as well as an increment in the cure rate. In the fifth experiment, splenectomy resulted in a decrease in the rate of tumor recurrence, but did not effect the ultimate cure rate.Although the nature of the immunological changes resulting from splenectomy are incompletely defined at present, these results provide encouragement in the search for immunological treatments for solid tumors.This work was supported in part by Contract No. N01-CM-73703 and Grant IR01CA-14768-01A1, both from the National Cancer Institute, National Institutes of Health, Department of Health, Education and Welfare, USA, and in part by a grant from the Chemotherapy Foundation of New York, Inc. 相似文献
918.
Synopsis
Raja erinacea and R. ocellata are sibling species which are positively correlated with each other by occurrence and numerical abundance. In sympatry the species undergo interactive segregation; R. erinacea feeds on a higher percentage of epifauna and R. ocellata feeds on a higher percentage of infauna.An isolated allopatric population of R. ocellata occurs in the Gulf of St. Lawrence which is phenotypically intermediate between the sympatric populations of R. erinacea and R. ocellata in characters related to feeding e.g. size, number of tooth rows in the upper jaw, and shape of the upper jaw. It appears probable that the allopatric population represents the morphological state of R. ocellata before it became sympatric with R. erinacea; divergence in size, number of tooth rows, and shape of the upper jaw between the two species developed after establishment of sympatry. These divergences in character traits, related to feeding, reduced competition between the two sympatric species and permitted the present wide overlap in their ranges.Character displacement is evidently rare in demersal fishes inhabiting the flat and soft bottoms of the northwestern Atlantic because the three other pairs of sibling species that occur there are parapatrically distributed and thus would not compete for resources. Raja erinacea and R. ocellata may have been restrained from establishing parapatry by another species pair of skates (R. senta and R. radiata) which have a complementary distribution and similar feeding habits of R. erinacea and R. ocellata but which occur in deeper water. 相似文献
919.
920.
Isocitrate lyase (EC 4.1.3.1) and malate synthase (EC 4.1.3.2), the two enzymes characteristic of the glyoxylate cycle, were demonstrated in promastigotes of five species of Leishmania (L. brasiliensis, L. donovani, L. mexicana, L. tarentolae, and L. tropica). Both enzymes were present in cells grown in a medium containing 10 mM glucose. Substitution of glucose with 20 mM acetate did not enhance enzyme levels. Acetate was readily taken up and metabolized by the cells. The distribution of label from acetate into various intermediary metabolites indicates a functional glyoxylate cycle and its role in gluconeogenesis/glyconeogenesis. The glyoxylate cycle in conjunction with alanine-glyoxylate aminotransferase and glyoxylate-aspartate aminotransferase could also be important in providing glyoxylate, the precursor for glycine biosynthesis. 相似文献