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11.
R C Strange B T Chapman J D Johnston I A Nimmo I W Percy-Robb 《Biochimica et biophysica acta》1979,573(3):535-545
1. The subcellular distribution of conjugates of cholic acid and chenodeoxycholic acid between cytosol, nuclei, mitochondria and microsomes in rat liver has been determined. 2. The partition coefficients for the distribution of these bile acids between subcellular fractions and buffer have been measured and used to construct a compartmental model of the amounts of conjugated bile acids present in the different subcellular organelles in vivo. 3. This model indicates that a large percentage of the bile acid in the rat liver is found in the nuclear fraction; 42% of the cholic acid conjugates and 27% of the chenodeoxycholic acid conjugates. Substantial amounts of bile acid are also present in microsomes and mitochondria suggesting that published estimates of the amounts of bile acids in these fractions are underestimates. 4. The model also allows the amount of bile acid which is in free solution in cytosol to be determined; 10.9% of the cholic acid conjugates and 4.1% of the chenodeoxycholic acid conjugates in rat liver were present in this fraction. Knowlege of the amount of free bile acid allows possible roles of the cytosolic bile binding proteins to be assessed. 相似文献
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Scaling of metabolic rate with body mass and temperature in teleost fish 总被引:27,自引:0,他引:27
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Long-column laboratory tests were performed to validate improvements to the MOFAT program for simulating LNAPL displacement and entrapment in response to a fluctuating water table. The long-column tests consisted of a fluctuating water table and its subsequent displacement and entrapment of an LNAPL. The modifications of MOFAT include a linear LNAPL trapping estimate and a new scaling technique for the inhibition portion of the fluctuation (water table rise). Improved prediction of the LNAPL trapping was obtained by assuming the amount of LNAPL that is trapped by a rising water table is proportional to the antecedent water content of the porous medium. The pressure-saturation relationship for the air-water drainage system was scaled to estimate the LNAPL-water and air-LNAPL drainage relationships. Scaled inhibition pressure-saturation relationships are improved by incorporating a correction for contact angle hysteresis and surface roughness. The incorporation of these changes into MOFAT led to noticable improvements in the numerical simulation of the experimental data. 相似文献
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Bacterial lipopolysaccharide (LPS) blotted to polyvinylidene difluoride (PVDF) membranes was detected by a technique adapted from current methodologies used to detect glycoproteins. PVDF-bound LPS was coupled to a hapten and localized on the membrane by Western blotting with an antibody-alkaline phosphatase conjugate specific for the hapten. Immobilon blots could be made reversibly transparent for photography and densitometry. 相似文献
18.
In the presence of a halobenzene or benzonitrile, Pseudomonas T-12 can produce substituted catechols from the corresponding substituted benzenes. A variety of monosubstituted benzenes with substituents containing up to four carbons, and some meta- and para- disubstituted benzenes, can serve as catechol precursors. 相似文献
19.
A R Yobs A E Plott M D Hicklin S A Coleman W W Johnston P R Ashton I F Rube J C Watts Z M Naib R J Wood 《Acta cytologica》1987,31(6):900-910
Two laboratories exchanged and rescreened a large sample of cases with cervicovaginal smears they had consecutively accessioned to examine the reproducibility of gynecologic cytodiagnosis under optimum conditions. At least a "working agreement" (diagnoses within +/- 1 category on a ten-category scale) was achieved in diagnoses of normal, benign reaction and squamous abnormality (from minimal dysplasia though invasive cancer) in 18,859 cases (96.8%), of endometrial abnormality in 21 cases (42%) and of "unsatisfactory" in 99 cases (20.7%). Larger differences occurred in greater than or equal to 30% of cases except in the categories of "normal" and "benign reaction," reaching a maximum of 82% for moderate dysplasia. Reexamining 382 cases decreased disagreement by category to the 20% to 65% range only in the five categories of dysplasia plus carcinoma in situ. Agreement was not predicated on the presence of endocervical cells or squamous metaplasia; the basis for "unsatisfactory" calls was not uniform. Comparison of the laboratories' diagnoses with referee diagnoses or, on 178 cases, with tissue diagnoses also demonstrated differences in diagnostic criteria. 相似文献
20.
P. J. Skuce C. F. Johnston I. Fairweather D. W. Halton C. Shaw K. D. Buchanan 《Cell and tissue research》1990,261(3):573-581
Summary The presence and distribution of neuropeptides belonging to the pancreatic polypeptide family have been demonstrated by an indirect immunofluorescence technique in the nervous systems of adult male and female Schistosoma mansoni. Seven antisera of differing regional specificity to pancreatic polypeptide (PP), peptide YY (PYY) and neuropeptide Y (NPY) were employed on both whole-mount and cryostat-sectioned material. Positive immunoreactivity (IR) was obtained with all antisera except an N-terminally-directed antiserum to NPY. In the CNS, immunoreactivity was restricted to cell bodies and nerve fibres in the anterior ganglia, central commissure and dorsal and ventral nerve cords of both sexes, whereas, in the PNS, positive-IR was present in the plexuses innervating the subtegumental musculature and the oral and ventral suckers. Intense immunoreactivity was observed in a plexus of nerve fibres and cell bodies in the lining of the gynaecophoric canal and in fine nerve fibres innervating the dorsal tubercles of the male. In contrast, in the female, strong immunoreactivity was evident in nerve plexuses innervating the lining of the ovovitelline duct and in the wall of the ootype, but most notably in a cluster of cells in the region of Mehlis' gland. Results suggest that molecules with C-terminal homology to the PP-family are present in S. mansoni. These peptides would appear to be important regulatory molecules in the parasite's nervous system and may play a role in the control of egg production. 相似文献