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281.
Protein I of Neisseria gonorrhoeae outer membrane is a porin 总被引:2,自引:1,他引:1
282.
283.
K Schulze R Kairam M Stefanski R Sciacca L S James 《Journal of applied physiology (Bethesda, Md. : 1985)》1981,50(5):1098-1103
A system of instrumentation for continuous measurement of gaseous metabolism and minute volume (VI) in the human newborn is described. O2 uptake and CO2 production are measured by open-circuit techniques utilizing a Servomex OA184 differential paramagnetic O2 analyzer and a BEckman LB-2 infrared CO2 analyzer. VI is measured with bias-flow pneumotachometry. Bench performance is described, methodological errors are defined, and clinical data are presented. The instrumentation is capable of safe, accurate, and continuous measurement of respiratory and metabolic variables in low-birth-weight infants. 相似文献
284.
An unusual conversion reaction and a related folk belief system are described in a Cape Verdean-American woman. A clinical approach is presented which stresses the need to negotiate between professional and popular explanatory models of illness. It is suggested that a significant factor in the successful management of this patient's symptoms was the acceptance of a mutually-understandable idiom for communication and treatment. 相似文献
285.
Mark J. Ottenbreit Susumu Inoue Ward D. Peterson James C. Lin 《Bioelectromagnetics》1981,2(3):203-215
Human marrow cells were irradiated with 2450-MHz CW microwaves in a fluid-filled waveguide irradiation system. Cell exposure was conducted by placing a marrow cell suspension in 20-μl glass microcapillary tubes that were positioned in the exposure chamber, and irradiated at power densities from 31 to 1,000 mW/cm2 (with corresponding specific absorption rates of 62 to 2,000 mW/g) for 15 minutes. The temperature of the sample was maintained at a fixed point. Sham-irradiated (SI) and microwave-irradiated (MWI) cells were cultured in a methylcellulose culture system for neutrophil colony proliferation. There was no reduction in neutrophil colony number on days 6–7 or 12–14 in cells exposed at 31 or 62 mW/cm2, but as the power density was increased to 1,000 mW/cm2, there was a reduction in colony number of MWI cells compared with SI cells. The microwave interaction with the human neutrophil colony-forming cells was apparently not related to temperature rise, or to the state of cell cycle, and was irreversible. 相似文献
286.
The effect of essential-fatty-acid deficiency on the activity of liver phosphatidate phosphatase in rats 下载免费PDF全文
The activities of the soluble and microsomal phosphatidate phosphatases (EC 3.1.3.4) are greater in the livers of essential-fatty-acid-deficient rats than in rats fed diets containing linoleic acid. 相似文献
287.
James C. W. Chen 《American journal of botany》1980,67(6):859-865
Polarizing and interference microscopes were employed to measure overall orientation of microfibrils and dry matter (expressed in optical thickness) in the cell wall of Nitella rhizoids. The microfibrils are aligned predominantly parallel to the cell's long axis (positively birefrengent), except in the apical dome where the arrangement appears to be random. The optical thickness, however, is greater at the very tip and the base region. The wall contains about 50-60% of acid extractable amorphous, noncrystalline substance. This extraction does not make a significant change in the alignment, but the remaining dry matter becomes less at the tip and increases slightly toward the base. The alignment parallel to the direction of cell growth in the rhizoidal cell is different from that of the elongating Nitella internodal cell where the alignment is transverse. 相似文献
288.
H. L. James J. C. Morrison W. D. Whybrew T. C. Trass E. T. Bucovaz 《Molecular and cellular biochemistry》1977,15(1):15-17
Summary Isoacceptor species of certain amino acidspecific transfer ribonucleic acids (tRNAs) were fractionated by gel permeation chromatography using Sephadex G-100. The separation is attributed to the 20% ethanol-1% NaCl solvent and to the characteristics of Sephadex. Isoacceptor tRNAs specific for cysteine, arginine, phenylalanine, and histidine were recovered from commercial tRNA of yeast by this method. Highly purified cysteine-specific tRNA, obtained by a method which would not be expected to separate isoacceptor molecules when fractionated by this procedure, was shown to contain two cysteine isoacceptor tRNAs.This investigation was supported in part by Public Health Service Research Grant AM-09131 from the National Institute of Arthritis and Metabolic Diseases. 相似文献
289.
James P. Butler 《Bulletin of mathematical biology》1977,39(5):543-563
The method of Green's functions is applied to the convection-diffusion equation describing gas transport in the human lung.
Explicit analytic solutions are found for the zeroth approximation to the value of steady state alveolar oxygen concentration, given the frequency of breathing, tidal volume,
oxygen consumption, alveolar volume, volume of the bronchial tree, and two modelling parameters describing the geometry. The
results of the calculation are compared favorably with some experimental data. 相似文献
290.
A web-like reticulum underlying the human erythrocyte membrane was studied at a resolution of 5–10 nm by means of a scanning electron microscope. The network was visualized in isolated membranes (ghosts) torn open to reveal their interior space and in residues derived from ghosts extracted with Triton X-100. It formed a continuous (rather than patchy) cover over the entire cytoplasmic surface, except where lifted off or torn away. Filaments (5–40 nm in diameter), annular figures (40–60 nm in diameter), and nodes (30–100 nm in diameter) were prominent in different networks. The dimensions of the filaments and the interstices in the reticulum varied with conditions, suggesting that the network has elastic properties. This reticulum is probably related to the erythrocyte membrane proteins spectrin and actin. 相似文献