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51.
José M. GUERRA-GARC 《动物学报》2007,53(1):179-183
铁锈笠螺是地中海最濒危的海洋无脊椎动物,对其生物学知之甚少,缺少对其活动节律和采食行为的了解。使用环氧树脂Eporai1127(原位标记了20个不同外壳长度的个体,并在每个外壳上标有不同的数字,作者在白昼或黑夜的高潮和低潮期收集了有关数据。可能由于云斑厚纹蟹(Pachygrapsus marmoratus)的捕食影响,铁锈笠螺白天的活动和运动多于夜间,但铁锈笠螺采食行为似乎仅限于高潮期。此外,汹涌的海面条件诱导了铁锈笠螺的活动和运动。 相似文献
52.
53.
Jennifer FA Swisher Devin A Haddad Anna G McGrath Gunther H Boekhoudt Gerald M Feldman 《MABS-AUSTIN》2014,6(6):1377-1384
Antibodies evoke cellular responses through the binding of their Fc region to Fc receptors, most of which contain immunoreceptor tyrosine-based activation motif domains and are thus considered “activating.” However, there is a growing appreciation of these receptors for their ability to deliver an inhibitory signal as well. We previously described one such phenomenon whereby interferon (IFN)γ signaling is inhibited by immune complex signaling through FcγRI. To understand the implications of this in the context of therapeutic antibodies, we assessed individual IgG subclasses to determine their ability to deliver this anti-inflammatory signal in monocyte-derived macrophages. Like IgG1, we found that IgG4 is fully capable of inhibiting IFNγ-mediated events. In addition, F(ab’)2 fragments that interfere with FcγRI signaling reversed this effect. For mAbs developed with either an IgG1 or an IgG4 constant region for indications where inflammation is undesirable, further examination of a potential Fc-dependent contribution to their mechanism of action is warranted. 相似文献
54.
M. P. Chernysheva A. D. Nozdrachev 《Journal of Evolutionary Biochemistry and Physiology》2017,53(1):1-16
The concept of the hypothalamus as a brain structure responsible for metabolic and thermal homeostasis of an organism emerged in the 60s and 70s of the XX century (hypothalamus as a homeostatic or thermal homeostat). In the following decades, studies of molecular mechanisms behind the genesis of circadian and circannual rhythms sinificantly expanded our knowledge of hypothalamic functions. According to current ideas, hypothalamic nuclei function as pacemakers for other structures and trigger various processes that have different temporal parameters (latency, velocity, duration, periodicity, sequentiality, density) and form together the organism’s endogenous time. In this review, the authors analyze some features of local networks in the hypothalamic nuclei and formulate the principles of neuropeptide action underlying the homeostatic regulation of the endogenous time by the hypothalamus. 相似文献
55.
Lazos-Monterrosa FA C Orantes-García O Farrera-Sarmiento AG Verdugo-Valdez MS Sánchez-Cortés LE Ruíz-Meza 《Phyton》2015,84(1):138-143
The tempisque (Sideroxylon capiri) is a tree native to Mexico used by the rural population for housing construction, poles and hedges, as fuel (wood) and also for fodder and ornamental purposes, among others. It is considered an endangered species. In order to contribute to its preservation and sustainable management, it was considered important to determine the proportion of viable seeds, the loss of viability due to storage period and the germination process by applying pregerminative treatments. We found that freshly collected seeds showed 100% viability, which decreased to 0% after 5 months of storage. According to the cumulative germination significant differences between treatments (p≤0.01) were found. It was observed that seeds can accelerate their time of germination with the previous exposure of 24 h in water at room temperature. The soaking treatment in water for 24 h at room temperature obtained final germination of 55%, while with the control 39% was reached. Soaking in hydrogen peroxide and scarification were the treatments with lower germination percentage (33 and 23%, respectively). To get a higher percentage of germinated seeds in a short time, it is necessary to give a soaking treatment in water for 24 h before sowing. 相似文献
56.
梨头霉11α—羟基化制备16β—甲基—11α,17α21—三烃基孕甾—1, … 总被引:1,自引:2,他引:1
选育到一株对16β-甲基-17α,21-二羟基孕甾-1,4=-二烯-3,20-二酮(Ⅱa)11α-羟基化活性强的梨头霉A28菌株,并发现底物21-乙酰化(Ⅱb)可明显提高11α-羟工 能力。在适宜的转化条件下,11b投料浓度0.5%,产物16β-基11α,17α,21-三羟基孕甾-1,4-二烯-3,20-二酮(Ⅲ)收率为73%,结构经波谱分析确认。 相似文献
57.
LIN WANG FA CUI JINPING WANG LI JUN ANMING DING CHUNHUA ZHAO XINGFENG LI DESHUN FENG JURONG GAO HONGGANG WANG 《Journal of genetics》2012,91(3):303-312
Grain protein content in wheat (Triticum aestivum L.) is generally considered a highly heritable character that is negatively correlated with grain yield and yield-related traits. Quantitative trait loci (QTL) for protein content was mapped using data on protein content and protein content conditioned on the putatively interrelated traits to evaluate possible genetic interrelationships between protein content and yield, as well as yield-related traits. Phenotypic data were evaluated in a recombinant inbred line population with 302 lines derived from a cross between the Chinese cultivar Weimai 8 and Luohan 2. Inclusive composite interval mapping using IciMapping 3.0 was employed for mapping unconditional and conditional QTL with additives. A strong genetic relationship was found between protein content and grain yield, and yield-related traits. Unconditional QTL mapping analysis detected seven additive QTL for protein content, with additive effects ranging in absolute size from 0.1898% to 0.3407% protein content, jointly accounting for 43.45% of the trait variance. Conditional QTL mapping analysis indicated two QTL independent from yield, which can be used in marker-assisted selection for increasing yield without affecting grain protein content. Three additional QTL with minor effects were identified in the conditional mapping. Of the three QTLs, two were identified when protein content was conditioned on yield, which had pleiotropic effects on those two traits. Conditional QTL mapping can be used to dissect the genetic interrelationship between two traits at the individual QTL level for closely correlated traits. Further, conditional QTL mapping can reveal additional QTL with minor effects that are undetectable in unconditional mapping. 相似文献
58.
N M Chernysheva V P Kaplan A G Konopliannikov T L Babaian L A Lepekhina 《Radiobiologiia》1991,31(3):381-386
The effect of mannan polysaccharide on the haemopoiesis recovery in irradiated mice has been investigated. Mannan has been shown to exert both the protective and the stimulatory effect: it accelerates restoration of femur bone marrow cellularity and nucleate cell number in the peripheral blood and causes a larger initial yield and subsequent more rapid postirradiation dynamics of pluripotent haemopoietic stem cells and precursor cells of granulocytes and macrophages. 相似文献
59.
Abstract We investigated the oviposition preference and larval performance of Helicoverpa armigera under laboratory conditions to determine if the oviposition preference of individual females on maize, cowpea and cotton correlates with offspring performance on the leaves of the same host plants. The host-plant preference hierarchy of females did not correlate with their offspring performance. Female moths chose host plants that contributed less to their offspring fitness. Plant effects accounted for the largest amount of variation in offspring performance, while the effects of female (family) was low. The offspring of most females (80%, n = 10) were broadly similar, but 20% (two out of 10), showed marked difference in their offspring performance across the host-plant species. Similarly, there was no relation between larval feeding preference and performance. However, like most laboratory experiments, our experi-mental design does not allow the evaluation of ecological factors (for example, natural enemies, host abundance, etc.) that can play an important role in larval performance in the field. Overall, the results highlight the importance of carrying out preference performance analysis on the individual or family level, rather than pooling individuals to obtain average population data. 相似文献
60.
G P German E V Chernokhvostova Y Y Vengerov M A Smirnova-Muiusheva A I Mishina T F Chernysheva M S Vinogradova L V Kupriyanova I N Sokova 《Journal of hygiene, epidemiology, microbiology, and immunology》1977,21(3):341-349
The levels of serum IgG, IgA and IgM were examined in 191 adults including 103 patients with various forms of meningococcal infection, 32 meningitis convalescents and 56 carriers, in order to elucidate the causes of different susceptibility to the meningococcal infection. The IgD level was determined in 54 meningitis patients as well as in convalescents and carriers. The amount of immunoglobulins was determined by radial immunodiffusion. The level of IgG at the beginning of the disease in patients with the generalized forms of meningococcal infection (meningitis, meningitis combined with meningococcaemia, meningococcaemia) was found to be considerably lower than in healthy subjects. The levels of all immunoglobulins, particularly of IgA and IgM, increased in the course of the disease. The levels of IgG, IgA and IgM in meningitis convalescents a year after recovery were found to be the same as in the controls. The levels of IgG, IgA and IgM in patients with meningococcal nasopharyngitis were significantly lower than in healthy subjects. The carriers showed a decreasd level of IgA and a considerably increased level of IgG while the levels of IgM and IgD did not differ from the control. 相似文献