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901.
902.
Francisco Gutirrez‐Corchero M. Victoria Arruga Lourdes Sanz Cristina García M. Angeles Hernndez Francisco Campos 《Molecular ecology resources》2002,2(1):75-77
FTA® cards were used for long‐term storage of avian blood samples. Blood DNA was extracted by a simple method and used in PCR for sex identification of adult and nestling Great Grey Shrikes Lanius excubitor. 相似文献
903.
In order to adapt to the fluctuations in soil salinity/osmolarity the bacteria of the genusAzospirillum accumulate compatible solutes such as glutamate, proline, glycine betaine, trehalose, etc. Proline seems to play a major
role in osmoadaptation. With increase in osmotic stress the dominant osmolyte inA. brasilense shifts from glutamate to proline. Accumulation of proline inA. brasilense occurs by both uptake and synthesis. At higher osmolarityA. brasilense Sp7 accumulates high intracellular concentration of glycine betaine which is taken up via a high affinity glycine betaine
transport system. A salinity stress induced, periplasmically located, glycine betaine binding protein (GBBP) of ca. 32 kDa
size is involved in glycine betaine uptake inA. brasilense Sp7. Although a similar protein is also present inA. brasilense Cd it does not help in osmoprotection. It is not known ifA. brasilense Cd can also accumulate glycine betaine under salinity stress and if the GBBP-like protein plays any role in glycine betaine
uptake. This strain, under salt stress, seems to have inadequate levels of ATP to support growth and glycine betaine uptake
simultaneously. ExceptA. halopraeferens, all other species ofAzospirillum lack the ability to convert choline into glycine betaine. Mobilization of thebet ABT genes ofE. coli intoA. brasilense enables it to use choline for osmoprotection. Recently, aproU-like locus fromA. lipoferum showing physical homology to theproU gene region ofE. coli has been cloned. Replacement of this locus, after inactivation by the insertion of kanamycin resistance gene cassette, inA. lipoferum genome results in the recovery of mutants which fail to use glycine betaine as osmoprotectant. 相似文献
904.
G M Pentelow 《BMJ (Clinical research ed.)》1983,286(6377):1532-1533
905.
The circulatory anatomy of the iliofemoral region was elucidated by doing detailed angiography in 50 cases, and we classified the vessels into 4 types. In most cases, the s.c.i.a. predominated over the s.i.e.a. Therefore, it is probably better to plan free flaps supplied by this artery. This vessel usually arises approximately two or three fingerbreadths inferior to the intersection of the femoral artery and the inguinal ligament, and the skin flap should be designed in the area inferior and parallel to the inguinal ligament. 相似文献
906.
907.
Marianne E. Walsh Charles M. Collins Thomas F. Jenkins Alan D. Hewitt Jeff Stark Karen Myers 《Soil & Sediment Contamination》2003,12(5):631-645
Fort Greely, Alaska has an extensive complex of weapon training and testing areas located on lands withdrawn from the public domain under the Military Lands Withdrawal Act (PL106-65). The Army has pledged to implement a program to identify possible munitions contamination. Because of the large size (344,165,000 m2) of the high hazard impact areas, characterization of these constituents will be difficult. We used an authoritative sampling design to find locations most likely to contain explosives-residues on three impact areas. We focused our sampling on surface soils and collected multi-increment and discrete samples at locations of known firing events and from areas on the range that had craters, pieces of munitions, targets, or a designation as a firing point. In the two impact areas used primarily by the Army, RDX was the most frequently detected explosive. In the impact area that was also used by the Air Force, TNT was the most frequently detected explosive. Where detected, the explosives concentrations generally were low (<0.05 mg/kg) except in soils near low-order detonations, where the explosive-filler was in contact with the soil surface. These low-order detonations potentially can serve as localized sources for groundwater contamination if positioned in recharge areas. 相似文献
908.
909.
910.
Viscoelasticity of packed erythrocyte suspensions subjected to low amplitude oscillatory deformation. 下载免费PDF全文
Concentrated adult erythrocyte suspensions were subjected to low amplitude oscillatory shear in a Weissenberg rheogoniometer equipped with a cone-and-plate assembly. The dynamic viscoelastic properties of the suspension were measured over a broad range of frequency by a numerical solution that accounted for fluid inertia. Variation of shear amplitude and cell volume percent, and comparison of buffered saline, plasma, and dextran as suspending media showed that the cellular elements had undergone small bending and shearing deformations. Studies of normal adult erythrocytes, hypotonically swollen cells, temperature-altered cells, and erythrocyte ghosts suggested that the method was evaluating membrane material properties. The normal membrane was found to exhibit a shear rate dependent elastic modulus that increased by more than a factor of 20 over a frequency range from 0.0076 Hz to 60 Hz. The membrane viscosity showed a substantial drop with frequency indicative of a frequency thinning phenomenon. At high frequency of deformation the viscous response of normal erythrocytes was no longer indicative of a membrane property due to the dominant influence of the internal hemoglobin solution. The studies generally supported the ability of the method to quantify relative membrane material properties and detect changes in membrane structure. 相似文献