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51.
In this study the possible effects of two predicted climate change scenarios on soil water regime of Hungarian Calcic Chernozem
soils has been investigated. Soil profiles classified as Calcic Chernozem — in total 49 — were selected from the MARTHA soil
physical database that incorporates soil data at national scale. These profiles were subdivided into three groups (sandy loam,
loam and clayey loam) in accordance with their mechanical composition. Soil water retention curves were scaled separately
for each of the three textural groups, using similar media scaling in order to represent the variability of soil hydrophysical
data with one parameter, the scaling factor (SF). Reference soil profiles were chosen according to the cumulative distribution
function of the scaling factor, six for each textural group. Daily downscaled meteorological data from A2 and B2 climate scenarios
of the Hadley Centre (2070–2100) and data from a reference period (RF, 1961–1990) were used in this study to characterize
different climatic situations. Nine representative years were selected in case of all the three scenarios, using the cumulative
probability function of the annual precipitation sum. Scenario analyses were performed, validating the SWAP soil water balance
simulation model for the 18 reference soil profiles and 27 representative years in order to evaluate the expected changes
in soil water regime under different from the present (RF) climatic conditions (A2 and B2 scenarios). Our results show that
the scaling factor could be used as a climate sensitivity indicator of soil water regime. The large climate sensitivity of
the majority of Chernozem soil subtypes water regime has been proven. 相似文献
52.
Suzanne J. Suchard Hilda K. Lo Lilly Y. W. Bourguignon 《Journal of cellular physiology》1988,134(1):67-77
In this study we have used a density perturbation method to isolate anti-Thy-1 antibody-induced Thy-1 caps from mouse T-lymphoma cells in the absence of detergents, and then compared the phospholipid composit on of these capped membranes with that of uncapped membranes. Initial phospholipid analysis by two-dimensional thin layer chromatography (2-D TLC) reveals a significant increase in the amount of 32P-labeled phosphatidylcholine in the Thy-1 capped membrane. In contrast, no significant changes are observed in the labeling of phosphatidylserine, phosphatidylethanolamine, or the sphingomyelins. Therefore, it is suggested that phosphatidylcholine may be involved in the organization and/or regulation of Thy-1 antigen redistribution. The composition of phosphoinositide in uncapped and capped membranes was analysed separately using one-dimensional thin layer chromatography (1-D TLC) to resolve phosphatidylinositol (PI), phosphatidylinositol 4-phosphate (PIP), and phosphatidylinositol 4, 5-bisphosphate (PIP2) from all other phospholipids. This analysis reveals a significant reduction in levels of PIP and PIP2, but not PI, in Thy-1 caps. Through the use of ion exchange column chromatography, we have found an increased production of all three species of inositol phosphates during anti-Thy-1 antibody-induced capping. Inositol 1, 4, 5 -triphosphate (IP3) shows the most significant increase, compared to the much smaller increases in inositol 4, 5-bisphosphate (IP2) and inositol monophosphate (IP). These results suggest that the binding of anti-Thy-1 antibody to Thy-1 antigen activates phospholipase C which, in turn, initiates polyphosphoinositide turnover and IP3 production. It is proposed that these observed effects are the result of early signal transducing events which are prerequisite steps in Thy-1 receptor cap formation. 相似文献
53.
Hilda Lewis 《BMJ (Clinical research ed.)》1960,1(5180):1197-1200
54.
Hilda Ritter-Studnička 《Plant Systematics and Evolution》1953,100(1-2):80-90
Ohne Zusammenfassung 相似文献
55.
Hilda B. Ritter 《Biotechnic & histochemistry》1958,33(4):167-170
A simplified technic for preparation of the aceto-orcein stain permits the storage of cells in the stain or squash preparations at room temperature for long periods without in* jury to or distortion of the cells and mitotic plates. Fresh cells from tumor ascites, tissue culture cells growing in free suspension or over cover slips, and homogenates of whole tissues are stained directly in a test tube in either (1) regular aceto-orcein and subsequently mounted in glycerol, or (2) aceto-orcein-glycerol mixture. These preparations are squashed for chromosome counts, and the permanent slides are kept from drying out by ringing the cover slip with Damar or Permount. 相似文献
56.
57.
T. S. Kumarevel S. C. B. Gopinath A. Hilda N. Gautham M. N. Ponnusamy 《World journal of microbiology & biotechnology》2005,21(1):23-26
Lipase from the oil-mill waste isolate Cunninghamella verticillata was purified by stepwise precipitation using acetone, as a sequel to our earlier conventional column chromatographic method [Gopinath et al. (2002)World Journal of Microbiology and Biotechnology 18, 449–458]. The yield of purified lipase was approx. 4-fold higher than by the previous method and the purified lipase was obtained with 70–80% acetone saturations. The enzyme was resolved as a single band with homogeneity both by native and by SDS–PAGE. The optimum condition for the lipase to crystallize was 5 g of enzyme in 0.05 M sodium phosphate buffer (pH 6.5) with 5 mM FeCl2 and 10% 2-methyl 2,4-pentanediol (MPD).These authors equally contributed to this work 相似文献
58.
59.
Hernández HM Figueredo M Garrido N Sánchez L Sarracent J 《International journal for parasitology》2005,35(13):1333-1337
Trichomonosis, caused by the protozoan parasite Trichomonas vaginalis, is one of the most frequent sexually transmitted diseases and is widely spread in all continents. Trichomonas vaginalis as well as other protozoan organisms have high levels of proteolitic activity mainly of the cysteine-proteinase type. This activity is necessary for recognition and adhesion of the parasite to the superficial epithelial cells of the host. In the present study, we show that intranasal immunisation with a 62 kDa cysteine-proteinase purified from T. vaginalis excretion-secretion products in combination with cholera toxin or with synthetic oligodeoxynucleotides (ODN) that contain unmethylated CpG motifs (CpG-ODN) elicits 62kDa specific IgG and IgA in vaginal lavage fluid and specific IgG in serum. This immunisation protocol resulted in enhanced elimination of parasites following intravaginal challenge of BALB/c mice. 相似文献
60.
Kavanaugh JS Rogers PH Arnone A Hui HL Wierzba A DeYoung A Kwiatkowski LD Noble RW Juszczak LJ Peterson ES Friedman JM 《Biochemistry》2005,44(10):3806-3820
Previous mutational studies on Tyr42alpha variants as well as the current studies on the mutant hemoglobin alphaY42A show that the intersubunit interactions associated with Tyr42alpha significantly stabilize the alpha1beta2 interface of the quaternary-T deoxyhemoglobin tetramer. However, crystallographic studies, UV and visible resonance Raman spectroscopy, CO combination kinetic measurements, and oxygen binding measurements on alphaY42A show that the intersubunit interactions formed by Tyr42alpha have only a modest influence on the structural properties and ligand affinity of the deoxyhemoglobin tetramer. Therefore, the alpha1beta2 interface interactions associated with Tyr42alpha do not contribute significantly to the quaternary constraints that are responsible for the low oxygen affinity of deoxyhemoglobin. The slight increase in the ligand affinity of deoxy alphaY42A correlates with small, mutation-induced structural changes that perturb the environment of Trp37beta, a critical region of the quaternary-T alpha1beta2 interface that has been shown to be the major source of quaternary constraint in deoxyhemoglobin. 相似文献