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1.
Breast cancer is the leading cause of cancer deaths among females, and it is estimated that each year, one in ten American women will be newly diagnosed as having the disease. It is therefore not surprising, that a great deal of effort has been made to better understand the biology of breast cancer, and that investigators keep up the search for new tools to better characterize, diagnose and treat these tumours. In this regard, the introduction of the hybridoma technique in 1975 by Kohler and Milstein has lead to an extensive work in the characterization of monoclonal and polyclonal antibodies against breast cancers. A large number of antibodies has been raised to different epitopes present in normal and neoplastic breast tissue; but unfortunately we have yet to find a highly sensitive and specific monoclonal antibody for breast cancer that can successfully be used for scintigraphic detection of nodal metastases and for radioimmunotherapy treatment of this disease.As possible radioimmunodiagnostics, antibodies are known which react with the following antigens:
  • 1.(1) cytoskeletal proteins
  • 2.(2) breast cell products
  • 3.(3) steroid receptors
  • 4.(4) putative tumor-associated antigens
  • 5.(5) oncogene products
  • 6.(6) pregnancy-related products
  • 7.(7) basement membrane antigens
  • 8.(8) degradative enzymes
  • 9.(9) cell receptors for extracellular matrix molecules
  • 10.(10) multidrug resistance gene product (p-glycoprotein)
  • 11.(11) proliferative markers.
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2.
  • 1.1. A simple procedure for isolation of high molecular weight genomic DNA, and RNA, from Streptococcus sobrinus OMZ176 is described.
  • 2.2. Cell cultures were grown aerobically for 10 hr.
  • 3.3. Spheroplast formation and lysis was achieved by mutanolysin/lysozyme-dependent digestion of the cell wall, followed by N-lauroylsarcosinate-mediated lysis.
  • 4.4. Nucleic acids were isolated directly from cell-lysates using cesium-trifluoroacetate (CsTFA) densitygradient centrifugation.
  • 5.5. Three different centrifugation regimes were tested: self-generated density gradients in a fixed angle rotor; self-generated density-gradients in a swinging-bucket rotor; pre-formed density-gradients in a swinging-bucket rotor.
  • 6.6. Genomic DNA isolated by the CsTFA-procedure was found to have higher purity as compared to genomic DNA isolated in a conventional CsCl gradient.
  • 7.7. Isolated DNA was shown to be of a quality suitable for applications in molecular biology.
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3.
  • 1.1. Twelve Large White × Landrace male pigs, six with high adrenocortical response to ACTH, and six with low response, were subjected to mild and moderate exercise, and then to insulin-induced hypoglycaemia.
  • 2.2. Plasma ACTH, cortisol, catecholamines and some haematological and plasma biochemical parameters were determined in response to exercise, and glucose and cortisol in response to insulin challenge.
  • 3.3. High responders had significantly greater increases than low responders in ACTH, cortisol and catecholamines following exercise, and in cortisol following insulin challenge.
  • 4.4. The results suggest that differences in adrenocortical response to exogenous ACTH are an accurate reflection of the animal's response to stressful stimuli.
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4.
  • 1.1. A lipoxygenase preparation was obtained from Thermoactinomyces vulgaris and was purified by affinity chromatography on a linoleyl aminoethyl sepharose column.
  • 2.2. Two active fractions were obtained.
  • 3.3. The fraction obtained by elution with 100 mM borate buffer pH 9.0 was used in the subsequent work.
  • 4.4. Th. vulgaris lipoxygenase oxidized linoleic acid into two products: 13-HPOD and 9-HPOD at a ratio of 44 to 56, respectively.
  • 5.5. The identification and characterization of the isomers was done by HPLC, I.R. and mass spectrometry.
  • 6.6. When arachidonic acid was used as substrate, 15-HPETE and 15-HETE were found to be the main enzymatic products.
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5.
  • 1.1. A high percentage (53%) of isolated snails injected with prostate gland homogenates lay eggs.
  • 2.2. These egg masses consist of a few eggs which contain many nonviable oocytes.
  • 3.3. Preliminary experiments suggest that an egg-laying factor may be present in prostatic secretions.
  • 4.4. Snails bred in isolation from hatching, whether injected or not, occasionally lay viable eggs.
  • 5.5. This observation shows that self-fertilization or parthenogenesis is, in fact, possible in Helix aspersa Müller.
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6.
  • 1.1. The locust vitellogenin (VTG) receptor which is embedded in oocyte plasma membranes is a glycoprotein.
  • 2.2. With various lectins oligosaccharide units have been identified, among them neuraminic acid linked to Gal or GalNAc, mannose chains, Gal linked to GalNAc or GlcNAc and fucose linked to GlcNAc.
  • 3.3. With specific enzymes it could be shown that mannose and most other oligosaccharides are O-linked while others like fucose are N-linked.
  • 4.4. Enzymatic removal of all O-linked carbohydrates resulted in a drop of the molecular mass of the receptor protein from 200,000 to 110,000.
  • 5.5. A total of N- and O-linked oligosaccharides of 54% was calculated.
  • 6.6. The isoelectric point of the receptor was found to be at pH 3.4 increasing slightly after removal of neuraminic acid.
  • 7.7. Removal of neuraminic acids destroyed the binding ability for VTG.
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7.
  • 1.1. A variety of haematological parameters were determined in adult Dasyurus viverrinus.
  • 2.2. Haemoglobin and red cell counts were high with a very low mean cell volume.
  • 3.3. Basophils are absent but the eosinophils contain small numbers of basophilic granules which may indicate a dual role for this cell.
  • 4.4. “Ring Form” leucocytes are present.
  • 5.5. Three types of red cell picture could be identified, some animals showing large numbers of spherocytes, spicule cells, and inclusion bodies.
  • 6.6. These cells resemble those found in some inherited human haemolytic anaemias but there was no evidence of haemolysis in the animals.
  • 7.7. An alkali resistant haemoglobin component is present.
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8.
  • 1.1. Subcellular location of dihydropyrimidinase and NCβA-amidohydrolase2 was studied in a cell suspension culture of tomato (Lycopersicon esculentum cv. Lukullus) and in Euglena gracilis.
  • 2.2. By differential centrifugation, crude extracts were separated into ten fractions. Activities of both enzymes were found mainly in cytosolic fractions marked by EDH (tomato) and glu-6-P-DH (E. gracilis).
  • 3.3. A cytosolic location was also found by a 20–60% and a 17.5–30% sucrose density gradients.
  • 4.4. Using mitochondrial marker enzymes such as fumarase, SDH, CS and MDH, a mitochondrial occurrence of both enzymes or their release from mitochondria can be excluded by sucrose gradient centrifugations. This can also be achieved using purified mitochondria prepared from tomato cells by two subsequent sucrose gradients.
  • 5.5. A possible vacuolar location of dihydropyrimidinase and NCβA-amidohydrolase was excluded by comparing their activities in isolated protoplasts and purified vacuoles which were characterized by their marker enzyme α-mannosidase.
  • 6.6. A nuclear location of both enzymes and/or their release from the nucleus during procedures used cannot be excluded.
  • 7.7. The results are discussed in relation to subcellular location to other pyrimidine-metabolizing enzymes in plant cells.
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9.
This paper comments on: Low, B. S., Alexander, R. D., and Noonan, K.M. Human hips, breast, and buttocks: Is fat deceptive? Ethology and Sociobiology 8: 249-247, 1987. In it I argue that:
  • 1.1. Sexual selection has probably not been the most important selection pressure on
  • 2.female human body shape.
  • 3.2. Male humans in different cultures find different aspects of the female body attractive
  • 4.and therefore are unlikely to have exerted consistent directional sexual selection on
  • 5.the female body.
  • 6.3. Breast size is not correlated with lactation success.
  • 7.4. Visible hip width is not correlated with parturition success.
  • 8.5. Women would lower their fitness if they tried to deceive men about their internal
  • 9.pelvic dimensions.
  • 10.6. There are many alternative hypothesis to explain the existence of fat onwomen's
  • 11.breast, hips, and buttocks.
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10.
  • 1.1. A lipoxygenase activity was purified from Thermoactinomyces vulgaris and some of its properties were characterized.
  • 2.2. The enzyme showed a temperature activity range of 40–55°C with still significant activity over 60°C.
  • 3.3. The pH of activity on linoleic acid had a broad range with an optimum at pH 6.0 and a weaker one at pH 11.0.
  • 4.4. On arachidonic acid the pattern was narrow bell-shaped with an optimum at pH 6.5.
  • 5.5. The purified lipoxygenase from Th. vulgaris showed an apparent Km of 1 mM and Vmax of 0.84 μmol diene/min/mg protein.
  • 6.6. It was inhibited by the oxidation products, 9-HPOD and 13-HPOD.
  • 7.7. A 160,000 Da molecular weight of the enzyme was determined by molecular filtration. Methionine, tyrosine, tryptophan and cysteine are apparently involved in its activity.
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11.
  • 1.1. In a continuing investigation of phycocyanin-membrane surface interaction, fluorescence quenching experiments were performed with a mixture of two populations of fluorescence probe-encapsulated phospholipid bilayer vesicles in the presence and absence of phycocyanin.
  • 2.2. These membrane vesicles were prepared with 1,2-dimyristoyl phosphatidylcholine (DMPC), cholesterol and a probe molecule.
  • 3.3. A fluorophore was encapsulated in one population of membrane vesicles, while a quencher was encapsulated in another population of membrane vesicles.
  • 4.4. The result was compared with those of experiments in the presence of other biomolecules, including albumin, cytochrome c, hemoglobin, myoglobin or RNA.
  • 5.5. Interestingly, a one-third reduction of the fluorescence intensity was observed in the mixture of these two populations of membrane vesicles in phycocyanin's presence.
  • 6.6. In contrast, the other biomolecules caused no significant reduction in the fluorescence intensity.
  • 7.7. These findings were evidence of a phycocyanin-induced membrane perturbation.
  • 8.8. This was further demonstrated by a phycocyanin-induced change in the thermotropic behavior of DMPC vesicles, as measured by differential scanning microcalorimetry.
  • 9.9. Such a unique property of phycocyanin is believed to be associated with its known membrane surface-interacting character.
  • 10.10. A possible phycocyanin-modulated membrane-membrane interaction was discussed.
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12.
  • 1.1. A method of maintaining the isolated lizard brain in a Ringer solution is described.
  • 2.2. Microelectrodes and EEG recordings from different areas of telecenphalon and optical tectum were made.
  • 3.3. The prolonged cells survival under the experimental conditions described has been demonstrated for several hours.
  • 4.4. The isolated brain of Lacerta makes it easy to reach anatomical pathways which otherwise, in the whole animal, would be more difficult to reach.
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13.
  • 1.1. Twenty-eight peptides were isolated from the egg jelly of sea urchins, Tripneustes gratilla, Pseudoboletia maculata, Strongylocentrotus nudus, Echinometra mathaei (type A and B) and Heterocentrotus mammillatus and their amino acid sequences were determined.
  • 2.2. Two of the peptides obtained from T. gratilla egg jelly possessed a bromophenylalanine (Br-Phe) residue in their sequences (Gly-(Br-Phe)-Asn-Leu-Asn-Gly-Gly-Gly-Val-Gly and Gly-(Br-Phe)-Asp-Leu-Asn-Gly-Gly-Gly-Val-Gly).
  • 3.3. All of the peptides elevated cyclic GMP concentrations in the spermatozoa of the respective sea urchin and caused a shift in the apparent mol. wt of a major sperm protein of the respective sea urchin.
  • 4.4. They stimulated respiration rates of the spermatozoa of Hemicentrotus pulcherrimus as well as their own species.
  • 5.5. One-half maximal concentrations of the peptides for respiratory stimulation of H. pulcherrimus spermatozoa were between 10−11 M and 10−9 M except a methionine-containing peptide which was about 10−7 M.
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14.
  • 1.1. Chemical structures were determined for the cuticular alkanes, alkenes, and certain of the alkadienes for 11 D. virilis group species.
  • 2.2. Male-specific hydrocarbons occurred in five species: these were 9-heneicosene in D. americana and D. novamexicana, 10-heneicosene in D. virilis, 5,13- and 5,15-pentacosadienes in D. kanekoi, and 9-pentacosene in one strain of D. lummei.
  • 3.3. Hydrocarbon profiles of newly emerged flies always differed from mature files.
  • 4.4. Relationships among the species, with respect to hydrocarbon profiles, were investigated by cluster analysis.
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15.
  • 1.1. An alkaline p-nitrophenylphosphate phosphatase has been purified 440-fold from extracts of Hatobacterium halobium.
  • 2.2. The enzyme has an apparent molecular weight of 24,000.
  • 3.3. A Km value for p-nitrophenylphosphate of 1.12mM has been found under optimal conditions.
  • 4.4. The enzyme is selectively activated and stabilized by Mn2+.
  • 5.5. It requires high salt concentrations for stability and maximum activity.
  • 6.6. It displays an unusual restricted substrate specificity of 25 phosphate esters tested, only phosphotyrosine and casein were hydrolysed besides p-nitrophenylphosphate.
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16.
  • 1.1. A population of Trigona fuscobalteata from Peninsular Malaysia was analysed for genetic variation at 9 gene-enzyme systems comprising 13 loci.
  • 2.2. Two gene-enzyme systems (phosphoglucomutase and isocitrate dehydrogenase) were polymorphic in the 20 colonies studied.
  • 3.3. Isocitrate dehydrogenase was represented by duplicate genes.
  • 4.4. The number of loci for several enzyme systems appeared to be different from that reported for the Australian stingless bees.
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17.
  • 1.1. The specific activity of GMP synthetase was measured in several human tissues and found to be highest in cultured skin fibroblasts, followed by bone marrow, leukocytes, erythrocytes. placenta, and liver.
  • 2.2. The enzyme from fibroblasts was purified approximately 50-fold by ammonium sulfate fractionation and gel filtration.
  • 3.3. The Km values were determined to be 4.9μM for XMP, 270μM for ATP. and 340 μM for glutamine.
  • 4.4. Ammonium sulfate could replace glutamine as the amino donor but was much less efficient.
  • 5.5. The enzyme was specific for ATP as the energy source.
  • 6.6. Unlike the calf thymus enzyme, the human enzyme has no requirement for a reduced sulfhydryl compound.
  • 7.7. Human GMP synthetase is inhibited by ATP, dATP, azaserine, and hydroxylamine.
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18.
  • 1.1. A new tetralysine endopeptidase from Escherichia coli AJ005 has been purified about 135-fold.
  • 2.2. The peptidase seems to be specific to tetralysine among lysine homopolymers.
  • 3.3. The optimal pH was about 7.5
  • 4.4. The activity was inhibited by KCN but not inhibited by soybean trypsin inhibitor.
  • 5.5. The apparent Km value was 2.5 × 1O−3 M for tetralysine.
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19.
20.
  • 1.1. Serum from the Pacific hagfish,Eptatretus stouti,contains a complement-like protein (CLP).
  • 2.2. CLP from unfractionated hagfish serum and from affinity-purified preparations binds to yeast cell surfaces.
  • 3.3. Incubation with CLP enhances the phagocytosis of yeast by hagfish leukocytes.
  • 4.4. CLP-mediated opsonization can be inhibited by anti-CLP antibody, EDTA, d(+)mannose and l(+)rhamnose.
  • 5.5. Additional opsomic factors are also in hagfish serum.
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