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51.
Annual production rates of reproductive organs inFagus crenata forests in the lower area of the species' range were studied using 10 litter traps in 1980–1986. The production rates of dispersed pollen were estimated by multiplying the number of fallen male inflorescences per ha per year by the mean amount of pollen per inflorescence before anthesis. Large annual fluctuations in the production rates of male and female inflorescences were recognized, whereas their annual trends were synchronized with each other. Pollen production rates were within the range 1.0–6900 (mean: 1630)×109ha−1 yr−1, the maximum/minimum ratio attaining 7000.F. crenata was the lowest producer of pollen among seven tree species studied: the number of pollen grains equivalent to a single ovule was in the range 6.0–14×104. Furthermore, the mean dry weight of a single pollen grain (3.77×10−5mg) was higher than for wind-pollinated species. Three factors seemed to cause the low seed fertility ofF. crenata. The dry-matter production rate in the best seed year reached 3252 kg ha−1 yr−1, of which pollen accounted for 259 kg ha−1 yr−1. Unproductive years with less than 10% of the maximum production occurred four times in a 7-yr period. In such years there were fewer male and female inflorescences, and more fruit dropped as a result of insect damage. Lower nut dissemination would play an important role in suppressing any increase in nut predators, and fewer flowers would be produced to avoid wastage of photosynthates in a cool-temperate climate.  相似文献   
52.
Protein kinase [EC 2.7.1.37] of human erythrocyte membranes was solubilized with 0.5 M NaCl in 5 mM phosphate buffer, pH 6.7 at 4 degrees C and purified on a CM-Sephadex C-50 column, followed by affinity chromatography on a histone-Sepharose 4B column. The purified protein kinase gave a single band (molecular weight; 41,000) on examination by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The optimum pH of the enzyme was 8.0 and a millimolar range of concentration of Mg2+ was required for its maximum activity. Histone and protamine were well phosphorylated by the protein kinase but casein and phosvitin were poor phosphate acceptors for the enzyme. The enzymic activity was not stimulated by cyclic AMP (cAMP). A cAMP-finding protein from human erythrocyte membranes inhibited the activity of the protein kinase, but the activity was restored with cAMP. A heat stable protein inhibitor from rabbit skeletal muscle also inhibited this enzyme. From these observations, this protein kinase seemed to be a catalytic subunit of the membrane bound cAMP-dependent protein kinase. This enzyme was strongly inhibited with Ca2+ in the presence of 1 mM MgCl2. Various sulfhydryl reagents and polyamines also had inhibitory activity on the protein kinase. Natural substrates of the enzyme were investigated using heat treated membranes and 0.5 M NaCl extracted membrane residues. Band 4.1, 4.2, and 4.5 proteins were phosphorylated but band 2 (spectrin) and band 3 proteins were poor substrates for this protein kinase.  相似文献   
53.
The membrane binding sites for lipopolysaccharide (LPS) were isolated by affinity chromatography of the solubilized membranes prepared from 125I-labeled mouse B-cells and T-cells on an affinity adsorbent prepared by coupling Salmonella minnesota R595 LPS to activated Sepharose 4B. The membrane proteins bound to the affinity adsorbent and eluted with 1.0% Triton X-100 were analyzed according to their mobility on polyacrylamide gel electrophoresis in sodium dodecylsulphate. These membrane proteins were further identified by immunoprecipitation with specific antisera. Immunoglobulins, possibly immunoglobulins M and D, were identified in the eluate from the B-cell membranes. The histocompatibility-2-complex proteins (H-2D, H-2K and Ia antigens) were also found to be binding sites for LPS on both B-cells and T-cells.  相似文献   
54.
For detection of ABO substances in the saliva of the cynomolgus monkey, the mixed cell agglutination reaction (MCAR) gave specific and clear results with a very small amount of saliva. Anti-A and anti-B antibodies in the sera of the same species showed the clearest hemagglutination by the saline agglutination method. The combined use of both methods was demonstrated to be easily and accurately applicable to the determination of human-type ABO blood groups of the cynomolgus monkey.  相似文献   
55.
The guanosine 3',5'-cyclic monophosphate (cGMP) level in the mouse splenic lymphocytes was increased about 2- to 3-fold by concanavalin A. This increase was completely dependent on the presence of Ca2+ in the medium. Homogenates of mouse splenic lymphocytes contained significant guanylate cyclase [EC 4.6.1.2] activity in both the 105,000 X g (60 min) particulate and supernatant fractions and both fractions required Mn2+ for full activity. Calcium ion (3mM) activated soluble guanylate cyclase 3-fold at a relatively low concentration of Mn2+ (less than 1mM) but inhibited the particulate enzyme slightly at all Mn2+ concentrations tested. Concanavalin A itself did not stimulate either fraction of guanylate cyclase. Thus these results suggest that elevation of the cGMP level in lymphocytes by concanavalin A might be brought about by stimulation of Ca2+ uptake and activation of soluble guanylate cyclase by the latter.  相似文献   
56.
Togaki  Daisuke  Doi  Hideyuki  Katano  Izumi 《Limnology》2020,21(2):267-267
Limnology - In the original publication of the article the sentence under the heading “Primer and probe design” was published incorrectly. The correct sentence is given in this correction.  相似文献   
57.
58.

Urban waterlogging stems from coverage with impervious surfaces and increasing rainfall intensity from climate change and variability, meaning that storm water cannot readily infiltrate the ground and excessive surface runoff leads to urban flooding. To reduce related environmental and safety risks, rainfall and groundwater level research was carried out in Kyoto Prefecture with two rain gardens (RG1 and RG2) to investigate flood mitigation functions using a tank model. During the 134 days of monitoring from July 14, 2017, to November 25, 2017, RG1 had seven overflow events with an average runoff control ratio of 63.94%, and RG2 had one event with a ratio of 95.97%. The RG1 tank model (two stages) showed that initial storage for the first and second depths was 6.912?×?10?11 and 0 mm, respectively. The heights of the discharge holes were 20.857 and 0.784 mm for the first stage and 0.659 mm for the second stage, and the discharge hole coefficients were 0.529 and 0.002 for the first stage and 0.004 for the second stage. The results showed that RG1 had penetration hole coefficients of 0.138 (first stage) and 0.254 (second stage), with a water balance error of 0.017 (<?0.02) and a Nash–Sutcliffe efficiency coefficient of 0.922, indicating better reliability and quality than RG2 with the one-stage tank model. Peak flow simulation for mitigation showed that RG1 had a high overflow control ratio (mitigation time 2 h for instant rainfall of 100 mm/h), and can therefore be considered appropriate for other urban areas of Japan.

  相似文献   
59.
Landscape and Ecological Engineering - In the original publication of the article, Figure&nbsp;1 was published incorrectly. The correct figure is given below.  相似文献   
60.
Journal of Plant Research - The article Molecular mechanisms mediating root hydrotropism  相似文献   
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