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951.
Takahashi N Tsukamoto Y Shiosaka S Kishi T Hakoshima T Arata Y Yamaguchi Y Kato K Shimada I 《Glycoconjugate journal》1999,16(8):405-414
N-glycans of neuropsin (serine protease in the murine hippocampus) expressed in Trichoplusia ni cells were released from the glycopeptides by digestion with glycoamidase A (from sweet almond), and the reducing ends of the oligosaccharides were reductively aminated with 2-aminopyridine. The derivatized N-glycans were separated and structurally identified by a two dimensional high-performance liquid chromatography (HPLC) mapping technique on two kinds of HPLC columns. Fourteen different major N-glycan structures were identified, of which 6 were high-mannose type (9.1%), and the remaining 8 were paucimannosidic type. The presence of insect specific N-glycan structures containing both 1,3- and 1,6- di-fucosylated innermost N-acetylglucosamine residue (23.3%), as below, was also confirmed by 600 MHz 1H-NMR spectroscopy. 相似文献
952.
953.
The Ca2+-free form of calmodulin (CaM), apocalmodulin (ApoCaM), regulates a variety of target proteins including nitric oxide synthase II (NOS-II). The CaM-binding site of NOS-II can bind ApoCaM with high affinity. Substitution of hydrophobic amino acids by charged amino acids at crucial positions 3, 9 and 13 within the CaM-binding motif did not abolish the ApoCaM interaction that occurred with significant affinity, though the affinity of the interaction was decreased remarkably. Isothermal titration calorimetry revealed that interaction of ApoCaM and synthetic NOS-II peptides was driven entropically. 相似文献
954.
Are corticosterone levels a good indicator of food availability and reproductive performance in a kittiwake colony? 总被引:7,自引:0,他引:7
We evaluated the use of corticosterone to gauge forage availability and predict reproductive performance in black-legged kittiwakes (Rissa tridactyla) breeding in Alaska during 1999 and 2000. We modeled the relationship between baseline levels of corticosterone and a suite of individual and temporal characteristics of the sampled birds. We also provided supplemental food to a sample of pairs and compared their corticosterone levels with that of pairs that were not fed. Corticosterone levels were a good predictor of forage availability in some situations, although inconsistencies between corticosterone levels and reproductive performance of fed and unfed kittiwakes suggested that this was not always the case. In general, higher corticosterone levels were found in birds that lacked breeding experience and in birds sampled shortly after arriving from their wintering grounds. All parameters investigated, however, explained only a small proportion of the variance in corticosterone levels. We also investigated whether corticosterone, supplemental feeding, year of the study, breeding experience, body weight, and sex of a bird were able to predict laying, hatching, and fledging success in kittiwakes. Here, breeding experience, year of the study, and body weight were the best predictors of a bird's performance. Corticosterone level and supplemental feeding were good predictors of kittiwake reproductive performance in some cases. For example, corticosterone levels of birds sampled during the arrival stage reliably predicted laying success, but were less reliable at predicting hatching and fledging success. Counts of active nests with eggs or chicks may be more reliable estimates of the actual productivity of the colony. Supplemental feeding had strong effects on kittiwake productivity when natural forage was poor, but had little effect when natural forage was plentiful. 相似文献
955.
A test battery was constructed on a palmtop computer for ambulatory purposes. This study explored whether the test battery could assess circadian rhythmicity under constant routine conditions. Performance, body temperature, and subjective sleepiness of 12 healthy subjects were measured. The test battery consisted of a sleepiness questionnaire and three performance tests: a vigilance detection test, a working memory test, and a choice-reaction time test. The subjects were divided into early-start and late-start groups and were subjected to the constant-routine protocol. All tests showed a trough in performance in the early morning around 07:00h and a peak in the evening between 21:00 and 23:00h. In addition, an afternoon decrement in performance was observed between 15:00 and 17:00h. On average, the circadian (peak-to-trough) variation of the performance variables amounted to 16.9%±1.7 SEM of the maximum across subjects. The late starters showed a larger impairment in performance during the morning than the early starters. This could be attributed to prior wakefulness. The characteristics of the performance rhythms found in this study replicate findings in several other studies carried out under constant routine conditions. In conclusion, the present test battery appeared to be a good tool for future assessment of performance under natural conditions. 相似文献
956.
Chromatographic determination of L- and D-amino acids in plants 总被引:1,自引:0,他引:1
Quantities of free L- and D-amino acids (L- and D-AAs) in plants (leaves of coniferous and decidious trees, fleshy fruits, leaf blades of fodder grasses, and seeds and seedlings of edible legumes) were determined. Amino acid (AA) enantiomers were converted into diastereomers using pre-column derivatization with o-phthaldialdehyde together with N-isobutyryl-L(or D)-cysteine followed by separation of the resulting fluorescent isoindol derivatives on an octadecylsilyl stationary phase using high-performance liquid chromatography. Relative amounts of D-AAs were also determined by enantioselective gas chromatography-mass spectrometry on Chirasil-L-Val. Free D-AAs acids in the range of about 0.2% up to 8% relative to the corresponding L-AAs acids were found in plants. D-Asp, D-Asn, D-Glu, D-Gln, D-Ser and D-Ala could be detected in most of the plants, and D-Pro, D-Val, D-Leu and D-Lys in certain plants. As D-AAs were detected in gymnosperms as well as mono- and dicotyledonous angiosperms of major plant families it is concluded that free D-AAs in the low percentage range are principle constituents of plants. 相似文献
957.
Kazuhiko?Yokota Yasunari?MatsunoEmail author Masaru?Yamashita Yoshihiro?Adachi 《The International Journal of Life Cycle Assessment》2003,8(3):129-136
Scope In this study, a dynamic model was built in which LCA and PBM were integrated to quantitatively assess the total environmental
impacts induced by the product population in a society over time. Specifically, a determination was carried out concerning
how Japan’s air conditioner population is used (lifetime distribution, number of units, etc.) and an assessment was made concerning
the Global Warming Potential (GWP) associated with the air conditioner population.
Methods The proposed dynamic model was applied to air conditioners for analyzing the total GWP caused by the air conditioner population
in Japan from 1990 to 2010. To create a trend forecast model for future environmental load, scenarios for air conditioner
production up to 2010 were formulated and the total GWP from the air conditioner population was predicted. Conducted also
were sensitivity analyses whose parameters were air conditioner performance, lifetime and the rate of refrigerant recovery
when retired units are processed.
Results and Discussion Applying the PBM to the air conditioner population in 2000, it was found that 81.5 million units consumed 5.94 x 10p10 kWh in that year, which was a 6.1 % increase in the total annual power consumption in 1990. In both a stationary scenario
and a steady growth (1.5% annual increase), it was found that the total GWP would be 27.7% higher than in 1990 under the stationary
scenario and 37.8% higher under the steady growth scenario. The improvements in air conditioner performance will have a small
effect on reducing the total GWP from that population. Furthermore, in connection with the average lifetime, it was found
that the GWP, due to refrigerant releases when units are disposed of, would be relatively large in 2000 and the following
years.
Conclusions Thus, shorter product lifetimes will spur a replacement of air conditioners with new units, a situation that will only lead
to the reduction of GWP if the recovery rate of refrigerant is to be achieved to more than 50% under the stationary scenario.
Recommendations and Outlook To meet COP3 targets for Japan in 2010 (i.e. to reach the same level as in 1990 for household appliances), our study shows
that it will be vital to raise the refrigerant recovery rate. If the number of air conditioners in use remains unchanged,
recovery would have to be 45.7%, but under the steady growth scenario it would have to be at least 60.4%. Therefore, it will
be difficult to meet COP3 targets unless the refrigerant recovery rate is strongly increased. This method is applicable to
assess not only the GWP of air conditioners, but also other environmental impacts caused by a variety of product populations,
which will be quite effective for setting targets of products’ performance, policymaking, etc. 相似文献
958.
Cognitive neuropsychology, cognitive anthropology, and cognitive archaeology are combined to yield a picture of Neandertal cognition in which expert performance via long-term working memory is the centerpiece of problem solving. This component of Neandertal cognition appears to have been modern in scope. However, Neandertals' working memory capacity, which is the ability to hold a variety of information in active attention, may not have been as large as that of modern humans. This characteristic helps us understand features of the archaeological record, such as the rarity of innovation, and allows us to make empirically based speculations about Neandertal personality. 相似文献
959.
猕猴桃籽有机成分的初步研究 总被引:3,自引:0,他引:3
对猕猴桃籽的水溶粗提物进行了清除H2O2的实验,结果表明粗提物对H2O2有清除能力,提示猕猴桃籽具有抗过氧化、延缓衰老作用的能力。目前大量废弃的猕猴桃籽有待合理开发利用,但其有机成分尚未见报道。本实验进行了猕猴桃籽的成分预分析,结果表明,猕猴桃籽含有生物碱、氨基酸、蛋白质、还原糖、油脂等,可能含有酚类、皂苷、三萜和甾醇等,不含有鞣质。利用高效液相色谱技术对其可能的有效成份进行了分离和纯化,得到3种纯的待鉴定的化合物。 相似文献
960.
Effects of dietary chromium chloride supplementation on performance,some serum parameters,and immune response in broilers 总被引:1,自引:0,他引:1
This study was conducted to investigate the effect of increasing dietary levels of inorganic chromium (CrCl3·6H2O) on the performance, blood chemistry, and immune response of broilers. Eighty newly hatched Ross PM3 broiler chicks were
evenly distributed to five groups of 16 chicks each. Two groups (control and only sheep red blood cell inoculated) were fed
the basal diet containing 2.2 and 4.5 mg Cr/kg and the remaining groups were fed 20, 40, or 80 mg/kg Cr-supplemented diets
for 44 d. Chicks in all groups, except in the control, at 3 and 5 wk of age, were injected intraperitonally with sheep red
blood cell for determining the primary and secondary antibody responses, respectively. When the chicks were 4 wk of age, a
delayed-type hypersensitivity test was performed. White blood cells were differentiated. Blood samples were collected for
the determination of serum proteins, glucose, cholesterol, cortisol, minerals, and alkaline phosphatase activity and for antibody
response. Chromium had no effect on weight gain, but 20 mg/kg supplemental Cr resulted in 18.57% reduction in feed consumption
and improved feed efficiency by 16.77%. Chromium did not affect serum cholesterol and P levels but reduced serum glucose and
increased serum protein, Cr, Ca, and Mg levels, and ALP activity. A slight reduction was observed with Cr supplementation
in cortisol levels. Slight but not significant increases were observed with Cr in serum Zn and Cu. Chromium increased the
ratio of bursa of Fabricius and liver to body weight. Heterophil and monocyte counts and heterophil/lymphocyte ratio were
reduced and lymphocyte counts, total antibody, IgG, and IgM titers were increased by supplemental Cr. All levels of Cr increased
the cell-mediated response to phytohemagglutinin. No alterations in tissues were observed by histopathological examinations. 相似文献