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961.
Identification of a new MAGE gene with tumor-specific expression by representational difference analysis 总被引:1,自引:0,他引:1
S Lucas C De Smet KC Arden CS Viars B Lethé C Lurquin T Boon 《Canadian Metallurgical Quarterly》1998,58(4):743-752
Early pregnancy in ruminants, such as the sheep, is characterized by relatively extensive development of the conceptus before attachment to the endometrium. Between the period of blastocyst hatching and initial attachment, the uterus responds to signals from the conceptus and adapts to provide an environment that permits the establishment of pregnancy. We used large-format two-dimensional (2D) PAGE to analyze the dynamic changes in protein composition of uterine luminal fluid (ULF) during this stage of pregnancy, and we determined the contribution of each of the extraembryonic membranes and the endometrium to these changes. The majority of the more than 40 pregnancy-associated proteins in ULF at Day 17 were secreted by the conceptus. By 2D gel map comparison and Western blotting, we identified transferrin, secreted by the yolk sac from Day 15, and cytoplasmic actin, one of the most abundant proteins produced by the trophoblast at Day 17. Apolipoprotein A1 and aldose reductase, whose abundance were markedly increased in pregnancy, were identified by peptide microsequencing. Aldose reductase, an enzyme required for the conversion of glucose to fructose, was shown to be synthesized by the trophoblast, and its detection even before the formation of the placenta suggests that the synthesis of fructose may occur much earlier than previously reported. 相似文献
962.
L Edelman P Rouger C Doinel H Garchon JF Bach J Reviron C Salmon 《Canadian Metallurgical Quarterly》1981,44(3):549-554
A murine anti-A monoclonal antibody was obtained by the hybridoma technique. This antibody, of an IgM nature, is capable of agglutinating A1, A2 and A3 red blood cells. Thermodynamic study confirmed its monoclonal character; its association constant is 1,6 10(6) l/mole. The enthalpy change of the antigen/antibody reaction is nul which indicates the absence of the role of temperature on antibody fixation. This weak affinity makes it necessary to concentrate the supernatant so as to enable use of these reagents under the same conditions as those used at present. 相似文献
963.
OBJECTIVES: The sentinel node is defined as the first-line axillary lymphatic drainage node in breast cancer. If the sentinel node can be identified, during axillary dissection for breast cancer, resection could be limited reducing subsequent morbidity. However, before modifying the standard dissection procedure, it is important to prove that the sentinel node is representative of the metastatic status of other axillary nodes. PATIENTS AND METHODS: Between March and December 1996, 86 patients (mean age 58 years, range 32-82) underwent amputation (n = 20), tumorectomy with dissection (n = 56) or tumorectomy followed by secondary dissection (n = 10) for breast cancer. Ten ml of diluted patent blue was injected either into the peripheral portion of the tumor or the tumorectomy cavity. Node dissection was performed 10 to 20 minutes after injection. The blue sentinel node was identified prior to standard dissection. RESULTS: A mean 12 nodes were removed (range 4-21). Seventy-nine sentinel nodes were identified (91%) and in 7 cases (8%) a sentinel node could not be identified. In 7 other cases the sentinel node was a false negative, i.e. non malignant despite metastases in other dissected nodes. In all the other cases, the status of the sentinel node predicted the status of the other nodes, i.e. a non-metastatic sentinel node associated with other metastatic nodes. Finally, in 7 cases, the sentinel node was the only invaded node among the nodes dissected. During the last 3 months of the study, the sentinel node was identified in 100% of the cases and was representative of the overall dissection. CONCLUSION: Identifying the sentinel node is an alternative to standard axillary node dissection procedures. The method requires a training period and identification can be improved with radioimmunologic guidance. Patient selection within the framework of a rigorous multidisciplinary protocol is indispensable. A nationwide study is currently being conducted to validate these preliminary results. 相似文献
964.
B Salmon C Cunningham AJ Davison WJ Harris JD Baines 《Canadian Metallurgical Quarterly》1998,72(5):3779-3788
Previous studies have suggested that the U(L)17 gene of herpes simplex virus type 1 (HSV-1) is essential for virus replication. In this study, viral mutants incorporating either a lacZ expression cassette in place of 1,490 bp of the 2,109-bp U(L)17 open reading frame [HSV-1(deltaU(L)17)] or a DNA oligomer containing an in-frame stop codon inserted 778 bp from the 5' end of the U(L)17 open reading frame [HSV-1(U(L)17-stop)] were plaque purified on engineered cell lines containing the U(L)17 gene. A virus derived from HSV-1(U(L)17-stop) but containing a restored U(L)17 gene was also constructed and was designated HSV-1(U(L)17-restored). The latter virus formed plaques and cleaved genomic viral DNA in a manner indistinguishable from wild-type virus. Neither HSV-1(deltaU(L)17) nor HSV-1(U(L)17-stop) formed plaques or produced infectious progeny when propagated on noncomplementing Vero cells. Furthermore, genomic end-specific restriction fragments were not detected in DNA purified from noncomplementing cells infected with HSV-1(deltaU(L)17) or HSV-1(U(L)17-stop), whereas end-specific fragments were readily detected when the viruses were propagated on complementing cells. Electron micrographs of thin sections of cells infected with HSV-1(deltaU(L)17) or HSV-1(U(L)17-stop) illustrated that empty capsids accumulated in the nuclei of Vero cells, whereas DNA-containing capsids accumulated in the nuclei of complementing cells and enveloped virions were found in the cytoplasm and extracellular space. Additionally, protein profiles of capsids purified from cells infected with HSV-1(deltaU(L)17) compared to wild-type virus show no detectable differences. These data indicate that the U(L)17 gene is essential for virus replication and is required for cleavage and packaging of viral DNA. To characterize the U(L)17 gene product, an anti-U(L)17 rabbit polyclonal antiserum was produced. The antiserum reacted strongly with a major protein of apparent Mr 77,000 and weakly with a protein of apparent Mr 72,000 in wild-type infected cell lysates and in virions. Bands of similar sizes were also detected in electrophoretically separated tegument fractions of virions and light particles and yielded tryptic peptides of masses characteristic of the predicted U(L)17 protein. We therefore conclude that the U(L)17 gene products are associated with the virion tegument and note that they are the first tegument-associated proteins shown to be required for cleavage and packaging of viral DNA. 相似文献
965.
The impact of interface customization on the effect of cognitive style on information system success
The paper investigates the impact that customizing the user interface has on the effect that the users' cognitive styles have on the success of an information system. The study was carried out on an office automation. (OA) system, which was implemented in an institution of higher learning to support the top administrators in their work. Pearson and Bailey's user information satisfaction (UIS) instrument was used to measure the success of the system, while the Myers-Briggs Type Indicator (MBTI) was used to determine the cognitive style of the user. The results provided evidence that support the proposition that by customizing the interface to suit the idiosyncrasies of the user, the effect that the cognitive style of the user has on the success of the OA system can be reduced, if not removed. This result suggests that if the interface to OA system can be customized, then system designers do not need to consider the users' cognitive styles explicitly when they are designing the system. 相似文献
966.
The in vitro activity of premafloxacin against 673 veterinary pathogens was evaluated. Premafloxacin was equivalent to ciprofloxacin, enrofloxacin, and danofloxacin in activity against the gram-negative bacilli but was much more active (MIC for 90% of the strains tested [MIC90], 0.015 to 0.25 microg/ml) than the comparison antimicrobial agents (MIC90, 0.13 to 16.0 microg/ml) against the staphylococci, streptococci, and anaerobes tested. 相似文献
967.
D Goldschmidt L Gordower JV Berthe M Remmelink C Decaestecker M Petein I Salmon R Kiss A Danguy 《Canadian Metallurgical Quarterly》1997,19(3):215-226
The antioxidative effect of CuZnSOD, which catalyzes the dismutation of superoxide anion (O2-), provides a defense against the oxygen toxicity. The object of the study is to evaluate the erythrocytes superoxide dismutase (SOD) activity in two groups of persons (Group I, healthy blood donors; Group II, lung cancer patients), using the spectrophotometric assay of NADH oxidation and the indirect method. The effect of trace elements, such as Al3-, Cr3+, Fe3+, Hg2+, NI2+, and Pb2+ (producing free radicals oxygen and present in pollution and smoke) is also evaluated. The results show the decrease of SOD activity in lung cancer patients with respect to healthy individuals. Likewise, in those patients the enzymatic activity is bigger in early stage (I,II) with respect to advanced one (III) (p < 0.05). The lesser activity when the samples are incubated with Ni or Pb point out that these metals play a role in neoplasm development. In short, the oxidant-antioxidant balance is altered in lung cancer patients. 相似文献
968.
SA Salmon JL Watts FM Aarestrup JW Pankey RJ Yancey 《Canadian Metallurgical Quarterly》1998,81(2):570-578
Minimum inhibitory concentrations were determined for selected antimicrobial agents against 872 bacteria isolated from intramammary infections in heifers in New Zealand (n = 401) and Denmark (n = 471). These values were reported in micrograms per milliliters. Antimicrobial agents tested against isolates from New Zealand were penicillin, cloxacillin, cephapirin, ceftiofur, novobiocin, enrofloxacin, erythromycin, and pirlimycin. The minimum inhibitory concentrations that inhibit 90% of the strains tested for these antimicrobial agents with Staphylococcus aureus were 4.0, 0.5, 0.5, 2.0, 1.0, 0.25, 0.5, and 1.0, respectively. The minimum inhibitory concentration values that inhibit 90% of the strains tested against the Staphylococcus spp. ranged from 0.5 to 1.0 for all antimicrobics. The minimum inhibitory concentrations against streptococci were < or = 0.06, 0.5, 0.13, 0.13, 4.0, 1.0, 0.13, and < or = 0.06, respectively. Antimicrobial agents tested against isolates from Denmark included penicillin, ampicillin, oxacillin, cephalothin, ceftiofur, penicillin plus novobiocin, erythromycin, and pirlimycin. Against S. aureus, the minimum inhibitory concentrations were 0.13, 0.5, 0.5, 0.5, 1.0, 0.25, 0.5, and 0.5, respectively. The minimum inhibitory concentrations against Staphylococcus spp. were 0.25, 0.25, 0.5, 0.5, 1.0, < or = 0.06, 0.13, 1.0, and 0.5, respectively. The minimum inhibitory concentrations against the streptococci were < or = 0.06, 0.13, 0.5, 0.5, 1.0, < or = 0.06, 0.13, 0.5, and 0.5, respectively. Minimum inhibitory concentration values for staphylococci from New Zealand and Denmark were similar to values reported for US isolates. Streptococci from New Zealand and Denmark had lower minimum inhibitory concentration values than did US isolates. Only ceftiofur and enrofloxacin were active against the Gram-negative bacilli. 相似文献
969.
Bucci Giacomo Pezzi Giovanni Salmon Mario 《Industrial Electronics, IEEE Transactions on》1984,(1):90-97
Ventilation is a technique for controlling the amount of both nicotine and tar delivered to smokers. VECOM is a system designed to control cigarette ventilation. It operates on every cigarette, on-line with the production process, taking measurements in accordance with a pneumatic model of ventilated cigarettes. Presented are the problems associated with performing on-line measurements, error correction, and overall system organization. 相似文献
970.
Transfection of modestly immunogenic tumors to express B7 family co-stimulator molecules results in their rejection by syngeneic mice, suggesting a possible clinical application in cancer patients. Immunization of naive mice with irradiated B7-1-transfected P1.HTR cells is sufficient to induce specific cytolytic T lymphocytes (CTL) and to protect against tumor challenge. However, patients to be treated will have an existing tumor burden; thus, preclinical models should examine therapeutic efficacy in an established tumor setting. Contrary to expectations, immunization of mice with irradiated B7-1-transfected P1.HTR cells had no impact on the growth of pre-established control-transfected tumors. Mice bearing control-transfected P1.HTR tumors successfully rejected living B7-1 transfectants on the contralateral flank, demonstrating the ability of tumor-bearing mice to respond to B7 co-stimulation. Inasmuch as IL-12 is another important factor for CTL maturation, P1.HTR transfectants expressing B7-1 and/or IL-12 were then constructed. Remarkably, regression of pre-established tumors was achieved following immunization with irradiated IL-12 transfectants, even without co-expression of B7-1. Rejection required a shared antigen with the tumor used for immunization, could not be reproduced with rIL-12 alone, depended on host T lymphocytes and correlated with a high IFN-gamma-producing T cell phenotype. In addition, IL-12-facilitated tumor rejection required co-operation with a CTLA-4 ligand provided by the host, and correlated with up-regulation of B7-1 and B7-2 on host antigen-presenting cells. Thus, active immunization in the established tumor setting is benefitted greatly by the provision of IL-12, which may recruit participation of sufficient B7 co-stimulation from the host that it need not be provided exogenously. 相似文献