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151.
Roy Robinson 《Genetica》1959,29(1):319-326
Summary An umbrous gene in the house mouse is described which is transmitted in crosses as a simple dominant. The same gene is capable of engendering a sable phenotype with yellow and an umbrous-agouti with white-bellied agouti. It assorts independently of the agouti locus, with which it was specifically tested, and probably of sex. The manifestation of the gene is briefly contrasted with other known cases of umbrous heredity. 相似文献
152.
153.
E. M. Nanson C. L. N. Robinson J. E. Merriman F. Sellers L. Horlick R. Hayton J. Lopez 《CMAJ》1967,96(3):140-143
At the University Hospital, Saskatoon, over the last three years, pacemakers have been inserted in 40 patients with complete or incomplete heart block. Fourteen of the patients were females and 26 were males. The average age was 65 years; 12 were over 80 years of age, and the youngest patient was 8 years of age. In none was the heart block due to operation. Thirty-three patients are still alive and well. There have been seven deaths three early and four late. One patient died because of a “runaway” pacemaker, and two as a result of infection persisting around the pacemaker. Twenty-nine Medtronic pacemakers were used and 14 Atricor pacemakers; currently we favour the latter instrument. 相似文献
154.
A method was developed for production of a freeze-dried Western equine encephalomyelitis vaccine from virus propagated in chick embryo cell culture monolayers maintained with a serum-free medium. A sufficient concentration of virus accumulated in the cell culture fluids prior to the occurrence of viral cytopathology to permit the production of a vaccine relatively free from serum and cellular proteins. Inoculation with two mouse ld50 doses of virus per 100 tissue culture cells was found to yield reproducible high virus titers at a convenient harvest time. These harvests were inactivated at 22 C by 0.05% formalin within 48 hr. Potency test results, as measured by the protection of immunized guinea pigs against an intracerebral virus challenge, indicated that the vaccine produced from the virus propagated in cell culture was equal in potency to a lot of whole chick embryo vaccine used to immunize laboratory and field workers subject to a high risk of infection. 相似文献
155.
Preacclimatization of men to heat by training 总被引:2,自引:0,他引:2
156.
Elizabeth B. Gargus Douglas H. Robinson James K. Bubien Lawrence B. Bugaisky Dale J. Benos 《In vitro cellular & developmental biology. Plant》1989,25(5):435-441
Summary Six- and seven-day post-coitus (p.c.) rabbit embryos have been cultured in an attempt to establish a trophectodermal cell
line. Results indicate that cells with epithelial characteristics (i.e. positive staining for cytokeratin) will survive in
culture until Passage 3. At that time a fibroblastlike cell becomes predominant. In addition, we have found that the presence
of the inner cell mass is required for embryo explants often results in the development of cells that spontaneously contract.
These cells stain positively for myosin, which indicates that they may be precardiac cells. Maximum diastolic potential was
−59±1.2 mV and the threshold potential was −53±2.3 mV. Spontaneously contracting cells did not respond to atropine, acetylcholine,
epinephrine, isoproterenol, or propranolol. Action potential seems to be a result of an inward calcium current, because the
beating rate is decreased in a dose-related manner with the calcium channel blocker verapamil, whereas the voltage-sensitive
sodium channel blocker tetrodotoxin was without effect.
This work was supported by grants HD21302, HD07069, DK31091, and HL37320 from the National Institutes of Health, Bethesda,
MD, with additional support from a University of Alabama at Birmingham Cardviovascular Research and Training Center Award. 相似文献
157.
158.
James M. Berger Paul J. Jackson Nigel J. Robinson Leah D. Lujan Emmanuel Delhaize 《Plant cell reports》1989,7(8):632-635
Suspension cultures of Datura innoxia cells were pulse-labeled with [35S]cysteine, then exposed to Cd to determine whether there is a direct precursor-product relationship amongst the different forms of the Cd-induced polypeptides, poly(-glutamylcysteinyl)glycines [(EC)nG, n=2 to 5]. Degradation of the polypeptides and possible regeneration of the [35S]-labeled glutathione and cysteine pools were also examined. After 2 h of exposure to [35S]cysteine, about 70% of the [35S]cysteine in the soluble fraction of the cell was incorporated into [35S]glutathione before exposure of the cells to Cd. One h after Cd exposure, most of the cellular [35S]glutathione was depleted and label was incorporated into (EC)nG. Analysis of [35S](EC)nG by reverse phase HPLC showed no direct precursor-product relationship between the synthesis of the shorter and longer chain forms. However, the rate of synthesis of the different polypeptides was linear for 32 h after Cd exposure. There was no evidence of degradation of [35S](EC)nG nor was it excreted into the medium within this period. From these results it is suggested that in the presence of Cd, a large pool of (EC)nG is unavailable for elongation to (EC)n+1G.Abbreviations (EC)nG
Poly(-glutamylcysteinyl)glycine
- HPLC
High pressure liquid chromatography
- CPM
Counts per minute 相似文献
159.
P R Baverstock S Illana P E Christy B S Robinson A M Johnson 《Molecular biology and evolution》1989,6(3):243-257
A rapid RNA sequencing technique was used to partially sequence the small-subunit ribosomal RNA (srRNA) of four species of the amoeboid genus Naegleria. The extent of nucleotide sequence divergence between the two most divergent species was roughly similar to that found between mammals and frogs. However, the pattern of variation among the Naegleria species was quite different from that found for those species of tetrapods characterized to date. A phylogenetic analysis of the consensus Naegleria sequence showed that Naegleria was not monophyletic with either Acanthamoeba castellanii or Dictyostelium discoideum, two other amoebas for which sequences were available. It was shown that the semiconserved regions of the srRNA molecule evolve in a clocklike fashion and that the clock is time dependent rather than generation dependent. 相似文献
160.
Nigel J. Robinson 《Journal of applied phycology》1989,1(1):5-18
Metallothioneins, MT's, are low-molecular-weight, cysteine-rich, polypeptides that complex ‘soft’ metal ions in thiol clusters.
They are structurally diverse. Some MT's are gene products, while others are secondary metabolites. Two of the three classes
of MT have been identified in algae. Eukaryotic algae possess the secondary metabolites referred to as class III MT. There
is no unequivocal evidence that MT genes occur in eukaryotic algae. However, the products of MT genes have been identified
in cyanobacteria. These genes and their metal regulatory elements remain to be isolated and characterized.
MT's have attracted interest from researchers involved in a wide range of disciplines including bioinorganic chemistry, biochemistry,
molecular biology, physiology, toxicology, environmental science and medicine. Although, the precise physiological roles of
these polypeptides remain undefined, a large number of functions have been speculated. These molecules chelate toxic trace
metals, such as Cd, thereby reducing the concentration of cytotoxic, free-metal ions. Furthermore, some MT's are believed
to be involved in zinc and copper homoeostasis. Future studies should reveal whether or not some of the diversity of MT structure
reflects a diversity of function. 相似文献