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As conventional treatments are unsuccessful, the survival rate of stage D3 prostate cancer patients is poor. Reports have suggested the existence of humoral and cell-mediated immunity (CMI) against prostate cancer tumour-associated antigens (TAA). These observations prompted us to treat stage D3 prostate cancer patients with an in vitro produced transfer factor (TF) able to transfer, in vitro and in vivo, CMI against bladder and prostate TAA. Fifty patients entered this study and received one intramuscular injection of 2–5 units of specific TF monthly. Follow-up, ranging from 1 to 9 years, showed that complete remission was achieved in 2 patients, partial remission in 6, and no progression of metastatic disease in 14. The median survival was 126 weeks, higher than the survival rates reported in the literature for patients of the same stage.  相似文献   
3.
Summary— Immunofluorescence and immunoelectron microscopy indicated that the antibody raised against the nuclear antigen Ki-67 of mammalian cells recognized antigenic determinants of early Drosophila embryos, localized on the outside of the nuclear envelope. Hence, the nuclear envelope of Drosophila appears to share a similar epitope with the chromosome scaffold of mitotic mammalian cells. With the progression of mitosis the antigen persisted around the mitotic spindle region and was also found in the pole regions at metaphase and anaphase. The antibody also stained the equatorial regions of the spindles from anaphase to late telophase. The antibody may therefore be used as a biochemical marker of the nuclear envelope for studying nuclear membrane biogenesis and behavior during the mitotic divisions of the Drosophila embryo.  相似文献   
4.
Stratigraphic analyses of organic carbon, organic nitrogen and algal and bacterial carotenoids in short cores of profundal sediments of four alpine lakes (Tovel, Leit, Paione superiore and Tom) were used to reconstruct their trophic history. In addition, depth distribution of carbonaceous particle concentrations provided information on lake contamination from atmospheric deposition. In three lakes (Tovel, Leit and Tom), sedimentary carotenoids unique to sulfur photosynthetic bacteria (okenone and isorenieratene) provide evidence of changes in the oxygen, light and sulfide conditions in the water column. All the lakes are oligotrophic or moderately productive, and the algal community is dominated by Chlorophyta, Pyrrhophyta and Cryptophyta. Cyanobacteria are rather poorly represented. The steep increase of carbonaceous particles in the uppermost sediment layers of all the lakes suggests that lake contamination by atmospheric transport of pollutants began in the 1940s to 1950s. These data, coupled with those from a parallel study on Chrysophycean scale-inferred pH, indicate recent acidification in those which are poorly buffered (Paione superiore and Leit).  相似文献   
5.
A new insoluble polymer containing a Cinchona alkaloid derivative has been synthesized and used as chiral ligand in the heterogeneous enantioselective dihydroxylation of olefins. It is shown that the enantioselectivity of the optically active diols obtained from both aliphatic and aromatic substrates is always comparable to that observed in the homogeneous phase under the same reaction conditions. A method for evaluating the enantiomeric excesses of the optically active products is also described. © 1995 Wiley-Liss, Inc.  相似文献   
6.
Summary The gene (fus) coding for elongation factor G (EF-G) of the extremely thermophilic eubacteriumThermotoga maritima was identified and sequenced. The EF-G coding sequence (2046 bp) was found to lie in an operon-like structure between the ribosomal protein S7 gene (rpsG) and the elongation factor Tu (EF-Tu) gene (tuf). TherpsG, fus, andtuf genes follow each other immediately in that order, which corresponds to the order of the homologous genes in thestr operon ofEscherichia coli. The derived amino acid sequence of the EF-G protein (682 residues) was aligned with the homologous sequences of other eubacteria, eukaryotes (hamster), and archaebacteria (Methanococcus vannielii). Unrooted phylogenetic dendrogram, obtained both from the amino acid and the nucleotide sequence alignments, using a variety of methods, lend further support to the notion that the (present) root of the (eu)bacterial tree lies betweenThermotoga and the other bacterial lineages.  相似文献   
7.
A circular dichroism-based detection system presents several advantages in the HPLC analysis of chiral compounds because of the selective monitoring of optically active molecules. Its use allows reliable determination of enantiomeric excesses and elution order. To this end, the application of empirical, semiempirical, and nonempirical methods to get stereochemical information from the CD signal is reported. Furthermore, recording the CD spectra on line and evaluation of the dissymetry factor make the CD detection very powerful in characterizing the stereochemistry of chiral eluates.  相似文献   
8.
Dihydroflavonol 4-reductase (DFR, EC 1.1.1.219) catalyzes the reduction of dihydroflavonols to leucoanthocyanins, a key "late" step in the biosynthesis of anthocyanins. In this study we showed that a strong reduction in DFR expression occurs in the non-red orange cultivar (Navel and Ovale) compared to that of the red orange (Tarocco) suggesting that the enzyme could be involved in the lack of production of anthocyanins. Therefore, we isolated and compared the cDNAs, the genomic clones, as well as the promoter regions of blood and blond orange dfrs. Our data revealed that the cDNA sequences of pigmented and non-pigmented orange DFRs were 100% homologous and contained a 1017 bp open reading frame which encodes a protein of 338 amino acid residues, corresponding to a molecular mass of 38010.76 Da, with a theoretical pI of 5.96. Moreover, we found that there were no significant differences in non-coding regions (introns and 5' upstream region) of dfr sequences. Southern blot analysis of genomic DNA indicated that dfr was present as a single copy gene in both cultivars. From these findings the low expression level of blond orange dfr, which might play a role in the phenotypic change from blood to blond orange, is thought to be the result of a likely mutation in a regulatory gene controlling the expression of dfr. In addition, here we reported the successful expression of orange DFR cDNAs leading to an active DFR enzyme which converts dihydroquercetin to leucoanthocyanidin, thus confirming the involvement of the isolated genes in the biosynthesis of anthocyanins. Moreover, as far as we know, this is the first report concerning the in vitro expression of DFR from fruit flesh whose biochemical properties might be very different from those of other plant organ DFRs.  相似文献   
9.
In this paper we propose a model of visual perception in which a positive feedback mechanism can reproduce the pattern stimulus on a neurons screen. The pattern stimulus reproduction is based on informations coming from the spatial derivatives of visual pattern. This information together with the response of the feature extractors provides to the reproduction of the visual pattern as neuron screen electric activity. We simulate several input patterns and prove that the model reproduces the percept.  相似文献   
10.
Increases in atmospheric temperature and nutrients from land are thought to be promoting the expansion of harmful cyanobacteria in lakes worldwide, yet to date there has been no quantitative synthesis of long‐term trends. To test whether cyanobacteria have increased in abundance over the past ~ 200 years and evaluate the relative influence of potential causal mechanisms, we synthesised 108 highly resolved sedimentary time series and 18 decadal‐scale monitoring records from north temperate‐subarctic lakes. We demonstrate that: (1) cyanobacteria have increased significantly since c. 1800 ce , (2) they have increased disproportionately relative to other phytoplankton, and (3) cyanobacteria increased more rapidly post c. 1945 ce . Variation among lakes in the rates of increase was explained best by nutrient concentration (phosphorus and nitrogen), and temperature was of secondary importance. Although cyanobacterial biomass has declined in some managed lakes with reduced nutrient influx, the larger spatio‐temporal scale of sedimentary records show continued increases in cyanobacteria throughout the north temperate‐subarctic regions.  相似文献   
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