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141.
Seligy VL Barbier JR Dimock KD Dove MJ Moranelli F Morosoli R Willick GE Yaguchi M 《Biotechnology advances》1984,2(2):201-216
New gene selection techniques (Recombinant DNA) are currently available to exploit useful properties of various biological systems hitherto regarded as interesting but of little or no immediate commercial value. The application of genetic engineering techniques to problems in the Pulp and Paper Industry are many. As a first step these techniques are being used to provide much needed fundamental information on the cellular and molecular mechanisms involved in the expression of extra-cellular enzymes that degrade lignocellulosic pulping wastes. The information gleaned from the studies on cellulolytic fungi and bacteria can be used to genetically engineer a yeast or bacterium capable of converting pulping wastes into ethanol and other useful by-products. 相似文献
142.
Summary A strong positive immunoreaction with an -endorphin antiserum occurs in two distinct sites of the goldfish and carp neurohypophysis. Fluorescent nerve terminals are found in the laminar nerve processes located in the rostral pars distalis, but the immunocytological reaction is mainly localised on the nerve processes of the posterior neurohypophysis lying between the intermediate lobe cells. Almost all the digitations of the neurohypophysis are strongly fluorescent. The immunoreactive fibres probably originate from the hypothalamus, where perikarya displaying the same immunoreaction have been found in the pars lateralis of the nucleus lateralis tuberis and in some minor centres. The possibility that the immunoreactive substances revealed on the neurohypophyseal processes may originate in the intermediate lobe cells is also discussed. It has now to be established if this hypothalamo-hypophyseal system contains a substance with endorphic properties or only some immunologically related substance devoid of the corresponding physiological activities. 相似文献
143.
The sporophyte foot of the mossTimmiella barbuloides consists of an unistratose epidermis of transfer cells, a parenchymatous cortex, and a small central strand consisting only of hydroids. The parenchymatous tissue of the vaginula develops one layer of transfer cells opposite the foot, whose lower extremity extends into the gametophyte stem's central strand. From the bottom to the top of the foot the ultrastructure of the sporophyte transfer cells shows some gradual changes that appear related to a functional specialization of these cells. According to a centripetal gradient, the quantity of plastid starch progressively lessens in both vaginula parenchyma and foot cortex. the observed morphological patterns suggest that in the foot-vaginula complex nutrients are translocated radially up to the sporophyte central strand. 相似文献
144.
The nature and distribution of hemotypes constituted by electrophoretic phenotypes in six loci, in a group of 183 Camargue horses, have been compared with those of five breeds of horses and ponies. The genetic similarities have been observed mainly with New Forest and Haflinger ponies, less with Barbs and Thoroughbreds, and the least with Arab horses. 相似文献
145.
146.
Leon R. Kass 《In vitro cellular & developmental biology. Plant》1981,17(12):1091-1099
Summary Modern science, dedicated since its 17th Century origins to the mastery and possession of nature for the relief of man's estate,
is a source of great social change, affecting our opinions, practices, and ways of life. It thus exists necessarily in tension
with law and morality, our institutions of stability and order. This tension between change and permanence, between science
and law or morals, was institutionalized by the American Founders who sought to encourage, under law, the progress in science
and the useful arts, by means of the copyright and patent laws. American science and technology have flourished under the
patent law, an ingenious ethical and social contract between scientists and the polity, through which private right and interest
and public good generally coincide. Nevertheless, this contract has its limitations. Some of these limitations are vividly
seen through the recent Supreme Court decision (in the Chakrabarty case) to permit the patenting of living microorganisms.
Analysis of this case shows why the contract between science and the polity embodied in the Patent Laws may not always serve
the public good and may also be harmful to science itself. Also, permitting ownership of living species shows how close we
have come in our thinking to overstepping the sensible limits of the project for the mastery and possession of nature. 相似文献
147.
A. L. Goldstein J. E. Palmer P. R. Johnson 《In vitro cellular & developmental biology. Plant》1981,17(8):651-655
Summary Primary fetal hepatocytes derived from Zucker rats with expectedfa gene frequencies of 0.0 and 0.75 have been established and can be used to detect early effects of thefa gene on hepatocellular metabolism. Paired incubation experiments demonstrate that protein synthesis in 0.75fa gene cultures is significantly less than in 0.0fa gene cultures under basal conditions. Insulin stimulates protein synthesis in 0.0fa gene cultures but has no effect on 0.75fa gene cultures. Cycloheximide inhibits protein synthesis in both types of culture. NH4Cl inhibits protein synthesis in 0.0 but not in 0.75fa gene cultures. These data suggest that fetal hepatocytes bearing thefa gene have in vitro a generally sluggish anabolic capacity and a blunted capacity to respond to insulin compared to fetal
hepatocytes without thefa gene. These diminished capacities may be expressions of a genetic error in lysosomal function.
A portion of this work was presented in preliminary form at the 1980 meeting of the Tissue Culture Association.
This work was supported in part by National Institutes of Health Grants AM19382 and AM06197. 相似文献
148.
Molecular cloning of bovine leukemia virus DNA integrated into the bovine tumor cell genome 总被引:3,自引:0,他引:3
The bovine leukemia virus (BLV) DNA harbored in the bovine tumor cell genome was cloned in lambda Charon 4A phage. Using either representative or 3' half-enriched BLV cDNA as a blot hybridization probe, clone lambda BLV-1 was shown to carry 9 kb of the BLV genome, flanked by cellular sequences at both ends. Restriction mapping with twelve endonucleases and hybridization of the DNA fragments to BLV cDNA representing a 3'-end portion of the viral genome revealed the presence and precise location of two long terminal repeats (LTRs) and virus-cell junctions. Thus, lambda BLV-1 appears to contain the complete BLV genome and flanking tumor cellular sequences. The restriction map of the cloned BLV proviral DNA closely resembles that previously reported for unintegrated linear proviral DNA, but differs significantly from that of the integrated provirus of another BLV isolate, the difference occurring preferentially in the putative gag and pol genes. 相似文献
149.
Biotechnology applied to mining of metals 总被引:3,自引:0,他引:3
Torma AE 《Biotechnology advances》1983,1(1):73-80
The present review describes the advances achieved during the last two years in the application of biotechnological principles in the extraction of metals from ores and minerals. Despite the fact that this branch of science is very young and many details are yet to be understood, the microbes are applied at commercial levels especially for the extraction of copper and uranium from low-grade ores. The technique is far from being developed to its full potential and it is generally recognized to be a technology of the future. The studies involved are complex and multidisciplinary in nature. 相似文献
150.
Liver tissues and fibroblasts from patients with propionic acidemia assigned to the pcc BC genetic complementation group have previously been shown to contain normal or near-normal quantities of structurally altered propionyl CoA carboxylases (PCC). Biochemical comparisons of PCCs from extracts of three livers and one placenta belonging to the pcc BC complementation group revealed that the K
m values for the enzyme's major substrates, propionyl CoA, bicarbonate, and ATP, and its monovalent activator, potassium, were similar to those of normal PCC. PCC in extracts of one of the livers, however, had an altered isoelectric point (pI = 5.4) compared to that of PCC from normal and other PCC-deficient tissues (pK = 4.6–4.7). Thermostability in the presence of sucrose or ATP differed among several of the mutant PCCs, including the PCC with an altered pI, and from that of normal PCC. To confirm these results and to determine whether valid inferences may be derived from comparisons of mutant and normal PCC in crude extracts, PCC was purified from normal liver and from one of the PCC-deficient livers. The biochemical parameters of the purified carboxylases were similar to those observed in liver extracts. These studies further-more confirmed that, whether purified or in extracts, PCC from the pcc BC group reflects structural mutations. Nevertheless, the abnormal enzyme structure appears to have no corresponding effect on the clinical features of the disorder in various affected individuals. Moreover, there is biochemical heterogeneity within the pcc BC complementation group that probably represents different interallelic gene mutations.This work was supported by NIH Research Grants Am 25675 and AM 26127. B. Wolf is the recipient of NIH Research Career Development Award AM 00677 and is aided by Basil O'Connor Starter Research Grant 5-263 from The National Foundation-March of Dimes. This article is No. 131 from the Department of Human Genetics at the Medical College of Virginia. 相似文献