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81.
Huckleberry plants evaluated at 13 sites in the southern Cascade Mountains of Washington State during August 1980 showed significantly lower fruit yields where subjected to heavy ash deposition following the 18 May 1980 eruption of Mt. St. Helens. High insect pollinator mortality is suspected as the major causal factor. The impact of such effects of volcanic activity on Native American subsistence is discussed. 相似文献
82.
83.
Helen K. Cooper Teresa Zalewska S. Kawakami K.-A. Hossmann P. Kleihues 《Journal of neurochemistry》1977,28(5):929-934
Abstract— Rats were subjected to cerebral compression ischaemia for 15min and were subsequently recirculated with blood for periods up to 3 h. In vivo incorporation of intravenously administered L-[1–14 C]valine into total brain proteins was found to be severely inhibited (about 20% of controls) after 45 min of recirculation. After 3 h, protein synthesis had increased, the specific radioactivity of proteins then being about 40% of controls. The post-ischaemic inhibition of protein synthesis was accompanied by a breakdown in polyribosomes and a concomitant increase in ribosomal subunits. In vitro incorporation of L-[1–14 C]phenylalanine by a postmitochondrial supernatant system derived from animals subjected to 15 min ischaemia and 15 min recirculation was also severely reduced and showed, in contrast to control animals, no response to the addition of a specific inhibitor of polypeptide chain initiation (Poly(I)). Together with the in vivo accumulation of ribosomal subunits this indicates a block in peptide chain initiation during the early stages of recirculation.
Polyribosomes from animals subjected to 15 min ischaemia without recirculation showed a normal rate of in vitro protein synthesis which was inhibited by Poly(I) to a similar extent as polyribosomes from control animals. These results suggest that the post-ischaemic inhibition in chain initiation develops during the early stages of recirculation rather than during the ischaemic period itself. 相似文献
Polyribosomes from animals subjected to 15 min ischaemia without recirculation showed a normal rate of in vitro protein synthesis which was inhibited by Poly(I) to a similar extent as polyribosomes from control animals. These results suggest that the post-ischaemic inhibition in chain initiation develops during the early stages of recirculation rather than during the ischaemic period itself. 相似文献
84.
85.
Christine Dreyer Helen Singer Peter Hausen Ursula Müller Elisabeth Siegel 《Development genes and evolution》1981,190(4):197-207
Summary A library of hybridoma cell lines has been established which produce monoclonal antibodies against antigens from the germinal vesicle ofXenopus laevis oocytes. Many of the antigens are also found in the nuclei ofXenopus embryonic cells in culture. The fate of two of these antigens during embryogenesis was traced by immunofluorescence on embryo and tadpole sections. Early in development these antigens appear to be evenly distributed in the nuclei of all cells. In later stages they gradually disappear from most embryonic structures but are strongly accumulated in the nuclei of some specific cell types and organs. 相似文献
86.
Several categories of social and individual behaviors were recorded during the first 60 days of life for seven stumptail macaques.
Mother-infant interactions tended to decelerate in synchrony with increases in infant nonsocial behaviors, such as object
manipulation. Several aspects of stumptail social growth during the first two months were similar to those of rhesus and other
macaques. Approaching-leaving, which has been used previously as an index of waning of the mother-infant bond, was due more
to infants than to mothers during the second month of life 相似文献
87.
Billie J. Wilson Gloria Porter Helen Kocvara Gaila Leo Douglas M. Strong 《Primates; journal of primatology》1978,19(1):195-201
Optimal conditions for the rhesus monkey micro mixed lymphocyte system with multiple automated harvesting of samples were
evaluated. Parameters studied were cell concentration, length of culture period, methods of inactivation of cell populations,
supplementation of media, type of culture plates, and changes in the reactivity of cells from individual animals over an extended
time period.
This work was supported in part by Portland Veterans Administration Hospital, Portland, Oregon, and the General Research Support
Branch of the U.S. Public Health Service Grant RR00163, the Bureau of Medicine and Surgery, Navy Department, Work Unit No.
M4318. 01.007ABG2. The opinions or assertions contained herein are the private ones of the authors and are not to be construed
as official or reflecting the views of the U.S. Navy Department or the Naval service at large. The animals used in this study
were handled in accordance with the provisions of Public Law 89–54 as amended by Public Law 91–579, “Animal Welfare Act of
1970,” and the principles outlined in the “Guide for the Care of Laboratory Animals,” U.S. Department of Health, Education,
and Welfare Publication No. (NIH) 73-23. 相似文献
88.
Dana A. Procsal Helen L. Henry Ernest J. Friedlander Anthony W. Norman 《Archives of biochemistry and biophysics》1977,179(1):229-234
The biological activity of 1α,24R,25-trihydroxyvitamin D3 [1α,24R,25(OH)3D3] was elevated in comparison to the hormonally active form of vitamin D3, 1α,25-dihydroxyvitamin D3 [1α,25(OH)2D3], in the rachitic chick in terms of its ability to (a) stimulate intestinal calcium absorption, (b) mobilize bone calcium, (c) induce intestinal calcium binding protein, (d) modulate the level of enzyme activity of the renal 25-OH-D3-1-hydroxylase system, and (e) interact with the intestinal cystosol-chromatin receptor system for the 1α,25(OH)2D3 receptor system. In each of these assays, the relative ratio of activity of 1α,24R,25(OH)3D3 to 1α,25(OH)2D3was (a) 25–50, (b) ca. 20, (c) 10, (d) 50, and (e) 36%, respectively. 相似文献
89.
Helen Kennedy 《Brittonia》1982,34(1):18-21
Calathea schunkei from San Martín Province, Peru, is described as new. This species is distinguished by the red bracts and unusual floral morphology. The petals do not reflex at anthesis, the outer staminode is lacking, and the stigma is blunt rather than the typical “scoop” shape. These unusual floral features are shared withC. timothei, a high altitude Colombian species. 相似文献
90.
Anterior segment mesenchymal dysgenesis: Probable linkage to the MNS blood group on chromosome 4 总被引:2,自引:1,他引:1 下载免费PDF全文
Robert E. Ferrell Helen M. Hittner Frank L. Kretzer James H. Antoszyk 《American journal of human genetics》1982,34(2):245-249
Thirty-seven blood samples were analyzed for linkage from members of a single family with an anterior segment mesenchymal dysgenesis (ASMD1) with variable expressivity affecting members of at least six generations. Maximum-likelihood analysis for linkage between ASMD1 and 14 biochemical and serological markers in the family showed a probable linkage between ASMD1 and the MNS blood group on the long arm of chromosome 4 (Z = 2.36 at a recombination fraction of .09). 相似文献