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81.
82.
Fatty acid synthesis from [14C]acetate was studied in the brownalgae, Fucus serratus and Fucus vesiculosus, which had beencollected from sites polluted by run-off from old copper mines.Algae collected from areas exposed to copper in situ showedchanges in the pattern of fatty acids labelled in vitro withan increase in oleate labelling and a decrease in palmitatelabelling in both species. The endogenous fatty acid patternsfor algae from polluted sites also differed from those fromunpolluted sites. Algae from sites polluted by copper containedmore oleate than samples from non-polluted sites. In addition,there were decreases in the polyunsaturated fatty acids -linolenate,octadecatetraenoate and docosapentaenoate for copper-exposedalgae. These differences are discussed with regard to the possiblemetabolic site of copper's action and to the relative toleranceof Fucus spp. to high environmental dissolved copper levels. Key words: Fucus spp., Copper pollution, Fatty acid synthesis 相似文献
83.
Allochthonous coarse particulate organic material in forest and pasture reaches of two south-eastern Australian streams 总被引:1,自引:0,他引:1
1. Terrestrial plant litter entering two forest and two pasture sites on upland streams in south-eastern Australia was measured over a 2-year period using traps suspended above the streams. Laterally transported terrestrial plant litter was also determined in one stream, but found to be only 10% of the total. 2. Litter accession to traps suspended above the stream was significantly lower at both forested sites than was litter fall in the adjacent riparian vegetation. 3. Litter input was high (600–700g DW m?2yr?1) and seasonal, with 30–50% of the annual total entering the stream during December—February (summer). However, seasonality was not as great as that recorded in Northern Hemisphere deciduous forest streams. 4. Leaves comprised the largest litter component, but represented a relatively smaller proportion of the litter than is usually the case in Northern Hemisphere deciduous forest streams; in contrast bark was a relatively large proportion of the litter. 5. At the sites flowing through pasture, litter accession was about two orders of magnitude lower than at the forested sites. 相似文献
84.
PAOLA A. FILOMENO KYUNG-PHIL KIM NARA YOON IRAN RASHEDI VICTOR DAYAN RITA A. KANDEL XING-HUA WANG TANIA C. FELIZARDO ELLIOT BERINSTEIN SALOMEH JELVEH ANDREA FILOMENO JEFFREY A. MEDIN PETER C. FERGUSON ARMAND KEATING 《Cytotherapy》2018,20(8):1001-1012
Background. Mesenchymal stromal cells (MSCs) promote wound healing, including after radiotherapy (RT) and surgery. The use of MSCs in regenerative medicine in the context of malignancy, such as to enhance wound healing post-RT/surgery in patients with soft tissue sarcomas (STSs), requires safety validation. The aim of this study was to determine the effects of human MSCs on STS growth in vitro and local recurrence and metastasis in vivo. Methods. Human primary STS and HT-1080 fibrosarcoma lines were transduced to express luciferase/eGFP (enhanced green fluorescent protein). Sarcoma cells were co-cultured or co-injected with bone marrow–derived MSCs for growth studies. Xenograft tumor models were established with STS lines in NOD/SCID/γcnull mice. To emulate a clinical scenario, subcutaneous tumors were treated with RT/surgery prior to MSC injection into the tumor bed. Local and distant tumor recurrence was studied using histology and bioluminescence imaging. Results. MSCs did not promote STS proliferation upon co-culture in vitro, which was consistent among MSCs from different donors. Co-injection of MSCs with sarcoma cells in mice exhibited no significant tumor-stimulating effect, compared with control mice injected with sarcoma cells alone. MSC administration after RT/surgery had no effect on local recurrence or metastasis of STS. Discussion. These studies are important for the establishment of a safety profile for MSC administration in patients with STS. Our data suggest that MSCs are safe in STS management after standard of care RT/surgery, which can be further investigated in early-phase clinical trials to also determine the efficacy of MSCs in reducing morbidity and to mitigate wound complications in these patients. 相似文献
85.
T. HORIE H. NAKAGAWA J. NAKANO K. HAMOTANI H. Y. KIM 《Plant, cell & environment》1995,18(9):1064-1069
Synthesis and validation of crop models for assessment of of the impact of elevated atmospheric CO2 concentration and anticipated global warming on crop production require crop response data obtained under field-like conditions. The temperature gradient chamber (TGC) with the facility for CO2 enrichment allows the creation of various CO2 and temperature regimes for crops over the entire growth period with relatively inexpensive construction and running costs. The TGC develops a temperature gradient along its longitudinal axis using solar energy during the day and heating at night while maintaining the natural diurnal cycle. The temperature gradient and the CO2 concentration in the TGC are regulated by computer control of the air ventilation rate through the TGC and of the CO2 release rate. Longitudinal gradients of CO2 concentration and water vapour pressure deficit of air in the TGC were generally less than 5% and ±0.2 kPa, respectively. A CO2 enrichment experiment on rice in the TGC showed that a doubling of the CO2 concentration markedly enhanced crop dry matter production. Temperature had less effect on dry matter production, although panicle dry weight was greatly decreased at higher temperature as a result of high-temperature-induccd sterility of rice spikelets. Since rice spikclets are most sensitive to high temperature at the moment of flowering, and their flowering habit is highly synchronized with the diurnal courses of environmental conditions, the TGC is a useful tool in understanding rice responses to changes in atmosphere and temperature. 相似文献
86.
87.
Jin KIM III 《Entomological Research》2004,34(3):157-158
A species of Scarabaeidae, Panelus parvulus Waterhouse and a species of Aphodiidae, Aphodius fossor (Linné) are newly recorded from Korea. The diagnosis and photographs of them are provided. 相似文献
88.
The tribe Ulomini of Korean Tenebrionidae is reviewed taxonomically. Korean Ulomini recorded to three genera and six species, Cneocnemis laminipes Gebien, Uloma marseuli Nakane, U. latimanus Kolbe, U. excisa Nakane, U. bonzica Marseul, Eutochia lateralis (Boheman). We have found that U. exciza was misidentified U. bonzica, and E. lateralis was not distributed in Korea as the result of this study. We confirm that two genera and four species are distributed in Korea. A key to diagnosis of the genera and species, and figures of these species are presented. 相似文献
89.
SYNOPSIS. Studies are described on the adenosine triphosphatase(ATPase) properties of myosin isolated from skeletal muscleof Coryphaenoides, a benthic fish captured at 2,200 meters depth.Ca2+-ATPase and EDTA-ATPase of Coryphaenoides myosin show thesame pH dependence as ATPase of mammalian myosin; however, ratesof ATP hydrolysis by Coryphaenoides myosin are only 510%of rates of ATP hydrolysis by rabbit skeletal myosin. Coryphaenoidesmyosin ATPase shows a decrease from Q10 of 2.0 at 25°C toQ10 of 1.4 a t 2°C, and undergoes irreversible denaturationat temperatures above 25°C. At pH 6.8 to pH 8.5, Coryphaenoidesmyosin ATPase undergoes activation by pressure at 25°C,but at 2°C shows negligible effect of pressure at valuesbelow 3,000 psi. The kinetic data on Ca2+-ATPase indicate valuesof 11 kcal/mole for H, 7.5 kcal/mole for TS, and 5.7cc/mole for V at 25°C, pH 7.6. Comparable data at 2°Cindicate values of 5 kcal/mole for H. 13 kcal/mole forTS, and negligible V. According to the results of 25°C,Ca2+-activatkm of myosin-ATP may involve disruption of fouror five hydrophobic or polar groups, presumably due to an "opening-up"of the myosin molecule at or near the site for ATP binding.It would also appear that Coryphaenoides myosin has undergonean adaptive change in the enzyme mechanism for ATPase such thatthe rate of ATP hydrolysis is relatively insensitive to pressureand temperature under conditions encountered by the living fish. 相似文献
90.
The investigations were designed to test osmotic adjustment,cell wall bulk elastic modulus and stomatal behaviour duringand after water stress and rewatering in the primary and firsttrifoliolate leaf of Phaseolus vulgaris. Leaf water relationsquantities fully recovered after rewatering within a few hours;diffusion resistance to vapour flow, however, required 6 h.Leaf growth recovery was considerably delayed. Osmotic adjustmentwas absent during water stress in both the primary and the firsttrifoliolate leaf. The bulk elastic modulus (v), however, waslower for the primary leaf (higher elasticity) than for thetrifoliolate leaves. These two types of leaves differed in theirdrought resistance in that the primary leaf exhibited wiltingat the end of the stress period (7 d) while the trifoliolateleaf remained relatively turgid. The bulk elastic modulus ofthe cell wall changed almost proportionally with the turgorpressure (p). The structure coefficient (), an indicator forthe intensity of change of the bulk elastic modulus with turgorwas higher for the primary than for the first trifoliolate leaf.The leaf diffusion resistance (r), below the turgor loss point,changed proportionally with the solute potential with very similarregression lines for the relation of (r) versus RWC 1. The datasuggest that greater drought resistance of the first trifoliolateleaf is related to a decreased bulk elastic modulus, but notto osmotic adjustment nor to differences in stomatal resistanceduring water stress. Key words: Phaseolus vulguris, Water stress, Recovery, Cell wall elasticity 相似文献