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231.
Jussi Tarkkanen Pentti Gröhn Erkki Heinonen Olof Alfthan Seppo Pyrhönen 《Cancer immunology, immunotherapy : CII》1981,10(4):251-255
Summary The effect of transfer factor (TF) immunotherapy on recurrent papillary bladder tumours (grade 0 papilloma and grade 1 and grade 2 carcinoma) has been studied. In a double blind study 27 patients received either TF derived from nonimmune normal donors or physiological saline. The follow-up period was 1 year. There was no difference between the two treatment groups with regard to clinical responses. Circulating immune complexes and responses to various skin test antigens were also analysed. Responses to skin test antigens and the level of circulating immune complexes did not correlate with clinical status, and TF had no effect on these parameters. 相似文献
232.
233.
Evgeniy N. Donev Marta Derba-Maceluch Zakiya Yassin Madhavi Latha Gandla Sivan Pramod Emilia Heinonen Vikash Kumar Gerhard Scheepers Francisco Vilaplana Ulf Johansson Magnus Hertzberg Björn Sundberg Sandra Winestrand Andreas Hörnberg Björn Alriksson Leif J. Jönsson Ewa J. Mellerowicz 《Plant biotechnology journal》2023,21(5):1005-1021
Trees constitute promising renewable feedstocks for biorefinery using biochemical conversion, but their recalcitrance restricts their attractiveness for the industry. To obtain trees with reduced recalcitrance, large-scale genetic engineering experiments were performed in hybrid aspen blindly targeting genes expressed during wood formation and 32 lines representing seven constructs were selected for characterization in the field. Here we report phenotypes of five-year old trees considering 49 traits related to growth and wood properties. The best performing construct considering growth and glucose yield in saccharification with acid pretreatment had suppressed expression of the gene encoding an uncharacterized 2-oxoglutarate-dependent dioxygenase (2OGD). It showed minor changes in wood chemistry but increased nanoporosity and glucose conversion. Suppressed levels of SUCROSE SYNTHASE, (SuSy), CINNAMATE 4-HYDROXYLASE (C4H) and increased levels of GTPase activating protein for ADP-ribosylation factor ZAC led to significant growth reductions and anatomical abnormalities. However, C4H and SuSy constructs greatly improved glucose yields in saccharification without and with pretreatment, respectively. Traits associated with high glucose yields were different for saccharification with and without pretreatment. While carbohydrates, phenolics and tension wood contents positively impacted the yields without pretreatment and growth, lignin content and S/G ratio were negative factors, the yields with pretreatment positively correlated with S lignin and negatively with carbohydrate contents. The genotypes with high glucose yields had increased nanoporosity and mGlcA/Xyl ratio, and some had shorter polymers extractable with subcritical water compared to wild-type. The pilot-scale industrial-like pretreatment of best-performing 2OGD construct confirmed its superior sugar yields, supporting our strategy. 相似文献
234.
Hydroxyurea not only inhibited the reduction of ribonucleotides, but also gave rise to need of exogenous methionine and thymidine for full growth in the cultures of Escherichia coli K12. In vitro the drug inhibited the formation of 5,10-methylenetetrahydrofolate by serine hydroxymethyltransferase in the cell extracts, which suggests that this reaction is a secondary target of hydroxyurea in the cells of E. coli. The syntheses of thymine nucleotides and methionine were also the most sensitive targets of hydroxylamine in the cultures of E. coli. 相似文献
235.
Purpose
The cities merit special attention in global warming since they produce up to 80% of the global greenhouse gas emissions. Even though this has been widely acknowledged, only few papers exist that have studied cities holistically from a demand, i.e., consumption, perspective. The study presents a detailed analysis of the carbon footprint of two metropolitan cities from a consumption perspective. With the analysis of consumer carbon footprints (carbon consumption), the distribution of emissions in the key source categories is presented and compared. 相似文献236.
Päivi Saari Sanna Saarnio Jussi V. K. Kukkonen Jarkko Akkanen Jaakko Heinonen Veli Saari Jukka Alm 《Biogeochemistry》2009,94(3):217-231
Forest clear-cutting followed by soil preparation means disturbance for soil microorganisms and disruption of N and C cycles.
We measured fluxes of N2O and dissolved organic carbon (DOC) in upland soil (podzol) and adjacent peat within a clear-cut forest catchment. Both soil
types behaved in a similar way, showing net uptake of N2O in the first year after the clear-cutting, and turning to net release in the second. The N2O flux dynamics were similar to those of N content in logging residues, as reported from a nearby site. As organic matter
is used in the food web of the decomposers, we attempted to explain the dynamics of N2O uptake and release by measuring the concurrent dynamics of the low molecular weight (LMW) fraction and the aromaticity of
DOC in a soil solution. The labile and most readily available LMW fractions of DOC were nearly absent in the year following
the clear-cutting, but rose after two years. The more refractory high molecular weight (HMW) fraction of DOC decreased two
years after the clear-cutting. The first year’s net uptake of N2O could be accounted for by the growth of decomposer biomass in the logging residues and detritus from the degenerating ground
vegetation, resulting in immobilization of nitrogen. Simultaneously, the labile, LMW fraction of DOC became almost completely
exhausted. The low availability of the LMW fraction could retard the growth and cause the accumulated decomposer biomass to
collapse. During the following winter and summer the fraction of LMW clearly increased, followed by increased N2O emissions. The presence of LMW DOC fractions, not the concentration of DOC, seems to be an important controller for N2O liberation after a major disturbance such as clear-cutting and site preparation. The complex connection between DOC characteristics,
nitrification or denitrification merits further studies. 相似文献
237.
Incubation of liver explants from second-trimester human foetuses with dexamethasone, glucagon or dibutyryl cyclic AMP (plus theophylline) increased the activity of liver cystathionase from unmeasurable or trace values to adult values. Simultaneous incubation with cycloheximide or actinomycin D inhibited this effect. 相似文献
238.
The relative rate of net DNA synthesis was stimulated when cells of dnaA mutants of Escherichia coli K12 were grown in the presence of low concentrations of DNA synthesis inhibitors. This led to a supernormal DNA/cell mass ratio. The excessive DNA was similar to the normal chromosomal DNA in size and stability in vivo. However, the cells did not divide but turned into long filaments. Excessive DNA synthesis in the presence of inhibitors of DNA synthesis was observed in the cultures of two independent dnaA mutants of E. coli, but dnaB and dnaC mutants behaved like the wild type in this respect. 相似文献
239.
Developing taste buds in the anterior mandibular floor of perihatching
chicks were studied by high voltage electron microscopic autoradiography in
order to identify proliferating gemmal cell types. Montaged profiles of 29
taste buds in five cases euthanized between embryonic day 21 and
posthatching day 2 were analyzed after a single [3H]thymidine injection
administered on embryonic day 16, 17 or 18. Results showed that dark cells
comprised 55% of identified (n = 900 cells) and 62% of labeled (n = 568
cells) gemmal cells as compared with light, intermediate, basal or
perigemmal bud cells. Dark cells had both a greater (P < 0.05) number of
labeled cells and a greater amount of label (grains/nucleus) than the other
four bud cell types, irrespective of injection day. The nuclear area
(micron 2) of dark cells was not significantly larger (P > 0.05) than
that of the other gemmal cell types and therefore cannot account for the
greater amount for label in the dark cells. Interestingly, only dark cells
showed a positive correlation (P < 0.003) between amount of label and
nuclear area. Results suggest that, during the perihatching period of
robust cell proliferation, dividing dark cells may give rise primarily, but
not exclusively, to dark cell progeny.
相似文献
240.
The major rivers of the South African ‘Lowveld’ (low-latitude savanna) suffer numerous impacts from upstream economic activities. Whereas monitoring these rivers is required to detect biodiversity losses, record pollution events and devise mitigation strategies, current monitoring programmes are inadequate. In 2009, the South African Earth Observation Network initiated an intensive long-term research programme on the Lowveld reaches of the Olifants River. Physico-chemical parameters, aquatic macroinvertebrates and fish abundances were recorded at four Lowveld sites in the Olifants River. We review six years of this programme. The results suggest deterioration in the ecological condition of the Olifants River with no discernible improvement through protected areas. Trends could not be detected. The parameters measured, sampling methods and/or sampling frequency might be responsible for the limited trends observed, or alternatively the results simply reflect stable conditions despite on-going pollution. Real time monitoring and an expansion in the parameters monitored would add value to the monitoring programme. 相似文献