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1.
Fillet samples of the toothfish Dissostichus eleginoides and D. mawsoni can be distinguished readily by muscle proteins revealed by isoelectric focusing and mitochondrial DNA markers. The proteins also distinguish toothfish from other species marketed under similar trade names.  相似文献   
2.
Chemical and biochemical crosslinking of membrane components   总被引:6,自引:0,他引:6  
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3.
PGRP-S (Tag7) is an innate immunity protein involved in the antimicrobial defense systems, both in insects and in mammals. We have previously shown that Tag7 specifically interacts with several proteins, including Hsp70 and the calcium binding protein S100A4 (Mts1), providing a number of novel cellular functions. Here we show that Tag7–Mts1 complex causes chemotactic migration of lymphocytes, with NK cells being a preferred target. Cells of either innate immunity (neutrophils and monocytes) or acquired immunity (CD4+ and CD8+ lymphocytes) can produce this complex, which confirms the close connection between components of the 2 branches of immune response.  相似文献   
4.
A clinical trial was undertaken to investigate the effects of Eleutherococcus senticosus (ES) and Panax ginseng (PG) on competitive club-level endurance athletes engaged in their normal in-season training. Participants were matched for training stress and received a 33% ethanolic extract (8 mL/day) containing either ES, PG (equivalent to 4 g and 2 g/day of dried root, respectively), or a placebo. A pre-test and post-test were used to evaluate the effects of six weeks of supplementation on cortisol, testosterone, and testosterone to cortisol ratio (TCR) as well as circulating numbers of total T-cells, T-helper cells (CD4), T-suppressor cells (CD8), CD4 to CD8 ratio, natural killer cells, and B lymphocytes. None of the immune system variables changed significantly nor showed any clear trend from pre to post test in any of the treatment groups. No significant change in testosterone, cortisol or TCR was observed in the PG group. In the ES group, however, TCR decreased by 28.7% from 0.0464 to 0.0331 (P=0.03). The main contribution to this decrease appeared to be a non-significant (P= 0.07) 31% trend towards increased cortisol rather than a very small non-significant (P = 0.36) 7% decrease in the calculated mean for testosterone. This result suggested that contrary to initial expectation, ES increased rather than decreased hormonal indices of stress, which may be consistent with animal research suggesting a threshold of stress below which ES increases the stress response and above which ES decreases the stress response.  相似文献   
5.
High-resolution proton and phosphorus nuclear magnetic resonance studies are reported on the self-complementary d(C1-G2-N3-G4-A5-A6-T7-T8-C9-O6meG10-C11-G12) duplexes (henceforth called O6meG X A 12-mer when N3 = A3 and O6meG X G 12-mer when N3 = G3), which contain symmetry-related A3 X O6meG10 and G3 X O6meG10 interactions in the interior of the helices. We observe inter-base-pair nuclear Overhauser effects (NOE) between the base protons at the N3 X O6meG10 modification site and protons of flanking G2 X C11 and G4 X C9 base-pairs, indicative of the stacking of N3 and O6meG10 bases in both O6meG X A 12-mer and O6meG X G 12-mer duplexes. We have assigned all the base and a majority of the sugar protons from two-dimensional proton-correlated and nuclear Overhauser effect experiments on the O6meG X A 12-mer duplex and O6meG X G 12-mer duplex in solution. The observed NOEs establish that the A3 and O6meG10 at the modification site and all other residues adopt the anti configuration about the glycosidic bond, and that the O6meG X A 12-mer forms a right-handed duplex. The interaction between the bulky purine A3 and O6meG10 residues in the anti orientation results in large proton chemical shift perturbations at the (G2-A3-G4) X (C9-O6meG10-C11) segments of the helix. By contrast, we demonstrate that the O6meG10 residue adopts a syn configuration, while all other bases adopt an anti configuration about the glycosidic bond in the right-handed O6meG X G 12-mer duplex. This results in altered NOE patterns between the base protons of O6meG10 and the base and sugar protons of flanking C9 and C11 residues in the O6meG X G 12-mer duplex. The phosphorus backbone is perturbed at the modification site in both duplexes, since the phosphorus resonances are dispersed over 2 parts per million in the O6meG X A 12-mer and over 1 part per million in the O6meG X G 12-mer compared to a 0.5 part per million dispersion for an unperturbed DNA helix. We propose tentative pairing schemes for the A3 X O6meG10 and G3 X O6meG10 interactions in the above dodecanucleotide duplexes.  相似文献   
6.
Our previous DNA sequence comparisons of 3' terminal portions from equivalent herpes simplex virus type 1 (HSV-1) and HSV-2 genes identified a conserved sequence (consensus YGTGTTYY; Y = pyrimidine) located approximately 30bp downstream from the AATAAA signal. We report here that this signal is located downstream from 67% of the mammalian mRNA 3' termini examined. Using constructions with the bacterial chloramphenicol acetyl transferase (CAT) gene linked to an HSV 'terminator' fragment, we show that deletions in the 'terminator' reduce CAT activities and the levels of CAT mRNA 3' termini. Specifically: (1) deletions of downstream sequences which extend up to the consensus YGTGTTYY signal reduce CAT levels to values 35% of those obtained with undeleted plasmids, (2) a deletion of a further 14bp, which removes the YGTGTTYY consensus but not the poly A site, reduces CAT activities to 1%-4%. The levels of CAT mRNA 3' termini reflect the reductions in CAT activities however, levels of mRNA 5' termini are unaffected by these deletions. The RNA produced in the absence of the YGTGTTYY signal is present in the cytoplasm although no CAT activity is detectable.  相似文献   
7.
8.
In order to study the epitopes in fibrin towards which monoclonal antibodies are directed we needed the pure individual polypeptide chains of human fibrinogen in reasonable quantity. We report here a simplified, rapid method of separation of high-purity human fibrinogen chains. Following reduction and S-carboxymethylation of human fibrinogen, the sample was injected directly onto a column of the polymeric reversed-phase perfusion packing POROS 20-R2, and the chains were completely resolved in less than 3 min at a flow-rate of 10 ml/min. The capacity was equivalent to that of a similar sized conventional silica-based column. However the throughput was approximately five to ten times as high. The column was durable and robust in day-to-day use.  相似文献   
9.
OBJECTIVE--To determine the effects of patient''s sex and area''s material deprivation on utilisation rates of coronary catheterisation and angiography in the investigation of ischaemic heart disease. DESIGN--Retrospective analysis of routinely collected hospital statistics. SETTING--Acute hospitals throughout Northern Ireland. SUBJECTS--24,179 episodes of patients discharged from hospital with a primary diagnosis of ischaemic heart disease and 1270 episodes relating to patients with an underlying diagnosis of ischaemic heart disease who had either coronary catheterisation or angiography. MAIN OUTCOME MEASURES--Age standardised admission rates for heart disease and age standardised utilisation rates for catheterisation or angiography, or both, for 566 electoral wards ranked by Townsend "deprivation" scores. RESULTS--Catheterisation-angiography rates in men were over fivefold those of women, ranging from 85.5/100,000 v 16/100,000 in patients from "well off" areas to 123/100,000 v 22/100,000 for patients from deprived areas. After admission rates for heart disease were controlled for, the overall rate ratio for women was 0.48 (95% confidence interval 0.38 to 0.60). After differential admission rates for heart disease and other potential clinical confounders were controlled for, the investigation rates of patients from the least and most "deprived" areas were not significantly different (rate ratio 1.04 (0.87 to 1.25)). CONCLUSION--Although investigation rates were significantly lower in women than in men, further clinical data would be required before labelling this underutilisation as evidence of bias. There was no significant difference in invasive investigation rates for heart disease in areas of varying deprivation or affluence.  相似文献   
10.
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