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91.
Transgenic 3.L2 T cells are stimulated by Hb(64-76)/I-Ek and are positively selected on I-Ek plus self-peptides. To this pool of self-peptides we have added a single, well-defined 3.L2 TCR antagonist (A72) in vivo. We find that mice expressing both the 3.L2 TCR and A72 have a minimal loss of T cells expressing the clonotypic TCR in the thymus and spleen. Importantly, the proliferative response of 3.L2 x A72 splenocytes is significantly reduced compared with splenocytes from 3.L2 mice. This reduced response can be attributed to peripheral antagonism. Thus we have identified a new class of self-ligands whose predominant effect is constitutive peripheral antagonism rather than negative selection. The net effect of these ligands is to avoid potential self-reactivity while maintaining as large a repertoire as possible.  相似文献   
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The effects of probiotics (Lactobacillus acidophilus and Bifidobacterium lactis), packaging (vacuum, 50% N2 + 50% CO2 or 100% CO2), storage temperature (4 and 10 °C) and storage time (90 d) on lipid oxidation, colour and microbial properties of sliced dry fermented sausage ‘sucuk’, which has a long storage time at low temperatures, was investigated. Probiotic‐added samples showed a significant reduction in the thiobarbituric acid‐reactive substances (TBARS) values compared with a control and starter culture groups. The analysis showed that control groups had the highest pH and that the pH was not affected by packaging or storage temperature. Probiotic use had a significant effect on total aerobic bacteria, lactic acid bacteria and Micrococcus/Staphylococcus counts, and bacterial counts decreased with storage time. The Enterobacteriaceae count was below detectable levels (<2.00 CFU g−1) throughout the storage period. The storage temperatures had no effect on the microbial counts. Packaging had a significant effect on lactic acid bacteria, and the highest value was determined with 50% N2 + 50% CO2. The addition of probiotics and the storage time resulted in a significant decrease of colour values (L*, a* and b*). Copyright © 2005 Society of Chemical Industry  相似文献   
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Climacterium is characterized by symptoms that occur as a result of the differentiation of hormonal equilibrium. It begins around the age of 40 and continues up to the age of 60. In this period cycles are usually anovulatory. This paper presents a case which may be diagnosed as abortus incompletus despite the patient being in menopause for five years previously.  相似文献   
96.
BACKGROUND: To examine the effect of endothelin-1 (ET-1) on spontaneous contractile activity and the effects of nimodipine and isradipine on ET-1-induced contractile responses in myometrial strips isolated from normal pregnant and preeclamptic women. MATERIAL AND METHODS:. Isolated myometrial strips were obtained from seven normal pregnant and seven preeclamptic women undergoing elective cesarean section and the strips were mounted in organ baths for recording of isometric tension. The effect of increasing concentration of ET-1 on spontaneous contractions and effects of increasing concentration of nimodipine and isradipine on ET-1-induced contractions were recorded. RESULTS: ET-1 dose-dependently (10(-11)-10(-8) M) increased the amplitude and frequency of spontaneous contractions in all myometrial strips obtained from normal pregnant and preeclamptic women. The increase in the amplitude of contractions in preeclamptic strips was significantly higher than that of normal strips. The increase in amplitude of contractions in normal and preeclamptic strips reached statistical significance beginning from the concentrations of 10(-9) M and 10(-11) M, respectively. ET-1 (10(-8) M) also increased the basal tone of all myometrial strips isolated from normal pregnant and preeclamptic women. When ET-1 (10(-8) M)-contracted myoinetrial strips were exposed to increasing concentrations of nimodipine (10(-6)-3x10(-5)M) and isradipine (10(-5)-3x10(-4) M), nimodipine and isradipine dose-dependently decreased the amplitude and frequency of contractions. CONCLUSIONS: The increase in contractile response with ET-1 was significantly higher in myometrial strips isolated from preeclamptic women compared to those of myometrial strips isolated from normal pregnant women. These increases in contractile response are at least in part mediated by dihydropyridine-sensitive calcium channels, since they were significantly reduced in the presence of increasing concentrations of nimodipine and isradipine.  相似文献   
97.
Loyalty to one's extended family, a well-known Japanese tradition, has broken down following World War II. Child rearing in Japan, therefore, has been changing gradually and clearly. Traditionally, child rearing was taught to young mothers by the grandmothers. However, recently young couples are no longer living with their parents. Therefore, there are no advisers nor consultants available at home for their child rearing. Commercialism has certainly invaded the field of child rearing, including too many guidebooks and even baby-sitting companies. Children's lives have become much more competitive, busy and unnatural in comparison with those of 20-30 years ago. This might be one cause of the increased incidence of bullying, school phobia and psychological disorders in children.  相似文献   
98.
Ergodic sum capacity maximization for CDMA:Optimum resource allocation   总被引:2,自引:0,他引:2  
We solve for the optimum signature sequence and power allocation policies that maximize the information-theoretic ergodic sum capacity of a code-division multiple-access (CDMA) system subject to fading. We show that at most N users may transmit at any given channel state, where N is the processing gain; and those users who are transmitting should be assigned orthogonal signature sequences. We also show that the power allocation policy that maximizes the capacity together with the choice of these signature sequences is single-user water-filling over sets of channel states that are favorable to each user. That is, the capacity maximizing signaling scheme is shown to dictate that the users allocate their powers and signature sequences in such a way that they always avoid interference from each other.  相似文献   
99.
Global warming is one of the most serious issues in today's world. Various innovative technologies have been proposed for the reduction of CO2 emissions and the mitigation of global warming. They include (1) the WENET project, inaugurated in 1993 by the government of Japan, in which electricity produced by photovoltaic systems in vast areas such as the Sahara Desert, or by hydropower systems, is converted to hydrogen for transport to demand sites, and (2) Steinberg's Hydrocarb process, in which fossil fuels and biomass are coprocessed to produce carbon and methanol. While Japan is resource-poor, it is located relatively close to Southeast Asia and Australia, which are large regions with abundant solar energy. This paper describes an investigation of the prospects for the adoption of these innovative technologies by Japan and surrounding resource regions in the next 30 to 40 years. An optimizing energy model is developed for the purpose, and the simulation results provide several interesting suggestions regarding Japan's future strategy for combatting global warming.  相似文献   
100.
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