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51.
52.
Metabolic effects of phenethyl alcohol on mammalian cells 总被引:1,自引:0,他引:1
53.
Conclusions Incubation of competent cells ofB. subtilis with a DNA-like subviral entity from vaccinia virus leads to the formation of complete vaccinia virus in the bacteria. The significance of this finding in regard to the concept of a universal genetic code is discussed.With 2 Figures in the TextA preliminary report of these results was presented at the XI. International Congress of Genetics in The Hague, September, 1963.Habilitandenstipendiat 1962/63 of Deutsche Forschungsgemeinschaft. 相似文献
54.
55.
The versatile temporoparietal fascial flap: adaptability to a variety of composite defects 总被引:3,自引:0,他引:3
The unique properties of the temporoparietal fascial flap (TPFF) offer adaptability in reconstruction of a variety of composite defects. The broad, thin sheet of vascularized tissue may be transferred alone or as a carrier of subjacent bone or overlying skin and scalp. As a pedicled flap, it is ideal for defects of the orbital, malar, mandibular, and mastoid regions. As a free-tissue transfer, the large vessels and lack of bulk find broad utility in reconstruction of the extremities. This flap is our choice for reconstruction of the dorsal hand and non-weight-bearing surfaces of the foot. A viscous gliding surface decreases friction for tendon excursion. The thin contour is aesthetically superior to thicker flaps, allowing unmodified footwear or gloves. The pliable fascia convolutes into surface defects (e.g., bone craters) or drapes over skeletal frameworks (e.g., ear cartilage). The rich capillary network offers nutrition to saucerized bone, cartilage or tendon grafts, and overlying skin grafts. The geometry of the skull lends to fabrication of membranous bone for complex facial puzzles. The donor site is well disguised by hair growth. Twelve cases performed over a 2-year period demonstrate the versatility of this flap. These include complex foot reconstruction, ear and scalp avulsion, shotgun wound of the cheek and orbit, posttraumatic jaw recontouring, chronic osteomyelitis of the hand and foot, and acute resurfacing of dorsal hand with tendon reconstruction. 相似文献
56.
Transformed plants with elevated levels of chloroplastic SOD are not more resistant to superoxide toxicity 总被引:29,自引:0,他引:29
The petunia nuclear gene which encodes the chloroplast isozyme of superoxide dismutase, SOD-1, has been fused with an efficient rbcS promoter fragment and 3 flanking region and introduced into tobacco and tomato cells. Transformed plants carrying this chimeric gene have up to 50-fold the levels of SOD-1 which occur in wild-type plants. However, tobacco plants with 30-to 50-fold the normal SOD-1 activity do not exhibit resistance to the light-activated herbicide paraquat. Similarly, tomato plants with 2-to 4-fold increases in SOD-1 do not exhibit tolerance to photoinhibitory conditions known to increase superoxide levels (high light, low temperatures and low CO2 concentrations). Our data indicate that increasing the chloroplastic SOD level in a plant cell is not sufficient to reduce the toxicity of superoxide. 相似文献
57.
ACTH/MSH(4-10) (10 micrograms/kg/b.i.d.; IP), administered to pregnant Sprague-Dawley rats during gestational days (GD) 3 to 12, significantly increased the metabolic activity of extensor digitorum longus (EDL) muscle at postnatal day 14. ACTH/MSH peptide, administered from day of birth to postnatal day 13, had no effect on EDL muscle metabolic activity using the 2,3,5-triphenyltetrazolium chloride indicator. By postnatal day 30, no differences were seen between the early prenatally treated group and saline controls. These results confirm our previous electrophysiological studies that showed that early prenatal ACTH/MSH(4-10) administration accelerates EDL muscle maturation. 相似文献
58.
Elizabeth A. Kingsley Teresa E. Carter Kevin D. Barrow Pamela J. Russell 《Cancer immunology, immunotherapy : CII》1996,41(6):348-354
A monoclonal antibody, BLCA-8, was raised against the human bladder cancer cell line, UCRU-BL-17CL. By flow cytometry and immunoperoxidase staining, this antibody was found to possess high specificity for bladder tumours, some reactivity with fetal tissues, and no reactivity with normal bladder, or any normal or malignant tissue. This high specificity and the stability of the antigen to the urinary environment suggest that BLCA-8 may have potential for use as an anti-bladder-cancer therapeutic agent. By thin-layer chromatography and autoradiography, BLCA-8 was found to bind four components within the neutral lipid fraction of a bladder cancer cell line, UCRU-BL-17/23. These components hadR
F values of 0.22, 0.16/0.15 (doublet), 0.12 and 0.08, and migrated below globoside, indicating the presence of more than four sugars. By enzyme-linked immunosorbant assay and thin-layer chromatography it was found that the binding of BLCA-8 to the lipid extract was increased by both mild alkaline hydrolysis and enzymatic treatments, indicating that adjacent phospholipids and glycolipids interfere with the accessibility of the antibody-binding site. Full biochemical characterisation of the BLCA-8 antigen is currently underway. 相似文献
59.
Summary We used in vitro growth inhibition assays to demonstrate that synthetic cecropin protein has potent activity against a range of plant pathogenic bacteria. We then prepared transgenic tobacco plants which express cecropin mRNA and protein. We have used Pseudomonas syringae pv tabaci infection of these transgenic tobacco as a model system to evaluate whether the plants which express cecropin protein also have increased tolerance to infection. We found no dramatic difference in disease response between plants which are expressing cecropin protein and control plants which were derived from the transformation with a binary vector which did not carry the gene encoding cecropin protein. 相似文献
60.
Alexander A. DiIorio Pamela J. Weathers Ronald D. Cheetham 《Applied microbiology and biotechnology》1993,39(2):174-180
Transformed root tissue of Beta vulgaris (Detroit Dark Red) was permeabilized to stimulate the release of intracellularly stored betanin without adverse affects on tissue viability as measured by biomass accumulation. Product release of up to 15% (w/w) was achieved by heat treatment at 42°C for 45 min with minimal effect on viability. Higher levels of product release were obtained with increasing temperature and exposure, but at the expense of viability. Viability was measured by comparing dry weight increases of permeabilized tissue 3 days after treatment vs non-permeabilized tissue over the same time interval. Recovery of heat-treated tissue was improved by addition of CaCl2 (20 mm for 10 min) post-heat treatment. Betanin release up to 15% was also obtained at ambient temperature (25°C) by addition of up to 20 mm (NH4)2SO4 in the presence of 1 mm ethylenediaminetetraacetic acid (EDTA).
Correspondence to: A. A. DiIorio 相似文献