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61.
Antisera against rat heart and liver fatty acid-binding protein (FABP) were applied in Western blotting analysis and ELISA to assess their tissue and intracellular distribution, and the influence of development, physiological conditions and several agents on the FABP content of tissue cytosols. The data obtained are compared with the oleic acid-binding capacity. Heart FABP is found in high concentrations in heart, skeletal muscles, diaphragm and lung, and in lower concentrations in kidney, brain and spleen, whereas liver FABP is limited to liver and intestine. In heart and liver, FABP is only present in the cytosol. The FABP content of both heart and liver shows a progressive increase during the first weeks of postnatal development, in contrast to their constant oleic acid-binding capacity. The reciprocally declining alpha-fetoprotein content of both tissues may partially account for the complementary fraction of the fatty acid-binding capacity. The FABP content and the fatty acid-binding capacity of adult heart and liver were in good accordance under various physiological conditions. Addition of clofibrate to the diet induces an increase of liver FABP content, whereas feeding of cholesterol, cholestyramine, mevinolin or cholate caused a marked decrease. The significance of the combined determination of fatty acid-binding capacity and FABP content (by immunochemical quantitation and blotting analysis) is indicated.  相似文献   
62.

Contaminant accumulation, distributions, geochemistry and mineralogy

Variability of the metal content of flood deposits  相似文献   
63.
Thirty-eight of 98 strains of Streptococcus uberis were shown to be carrying lysogenic phage. Although propagating strains were rare, host modification by field strains sensitive to phage was used to increase the lytic spectra. When 120 nationally-collected strains were challenged with 25 phages, selected on the basis of differing lytic spectra and propagating strains, 30% were susceptible to at least one phage, increasing to 42% when 480 strains from a single farm were considered. A typing system based on susceptibility to lytic phage was considered feasible.  相似文献   
64.
The in-vitro efficacy of commercially available topical antimicrobial products against control strains and those from clinical material are compared with an agar diffusion model. The MICs of the constituent antimicrobial compounds have been determined for the same organisms. Plotting the inhibition zone diameters produced by the topical products against the log10 MICs of their constituent antimicrobial compound(s) gives overall product performance profiles for a range of organisms. These profiles confirm that the formulation of a topical product clearly modifies the response obtained with a specific antimicrobial compound.  相似文献   
65.
Organization of hindbrain segments in the zebrafish embryo   总被引:17,自引:0,他引:17  
B Trevarrow  D L Marks  C B Kimmel 《Neuron》1990,4(5):669-679
To learn how neural segments are structured in a simple vertebrate, we have characterized the embryonic zebrafish hindbrain with a library of monoclonal antibodies. Two regions repeat in an alternating pattern along a series of seven segments. One, the neuromere centers, contains the first basal plate neurons to develop and the first neuropil. The other region, surrounding the segment boundaries, contains the first neurons to develop in the alar plate. The projection patterns of these neurons differ: those in the segment centers have descending axons, while those in the border regions form ventral commissures. A row of glial fiber bundles forms a curtain-like structure between each center and border region. Specific features of the individual hindbrain segments in the series arise within this general framework. We suggest that a cryptic simplicity underlies the eventual complex structure that develops from this region of the CNS.  相似文献   
66.
Summary Prolactin (PRL) binds to the testis of mice and rats where it increases the number of luteinizing hormone receptors, increases the binding of human chorionic gonadotropin (hCG) to LH receptors, and enhances testosterone synthesis and secretion. PRL also binds to the prostate and seminal vesicles of rats and humans where it increases organ weight and stimulates growth and uptake of testosterone. PRL binds to the epididymis of rats but the effect of PRL on this organ is unknown. In the present study, a standard immunoperoxidase (PAP) technique was used to detect the binding of endogenous and exogenous PRL or PRL-like peptides to the epididymis of the mature mouse. Throughout the epididymal duct, a positive reaction for peroxidase, suggesting PRL or PRL-like binding, occurred in the Golgi area of principal cells. In segment 1, positive reactions were also visualized in the perinuclear area and in the region located between the Golgi area and the apical surface of the principal cells (supra-Golgi area). In the corpus and cauda epididymidis, scattered entire principal cells were also positive. Throughout the epididymal duct, the reactions indicating the binding of exogenous PRL were slightly stronger than those testing for binding of endogenous peptides. The significance of such binding to the epididymis is uncertain but PRL may perform the same functions in epididymal principal cells as it does in the testis, prostate, and seminal vesicles.  相似文献   
67.
Cell migration in the embryo and adult organism   总被引:1,自引:0,他引:1  
  相似文献   
68.
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70.
Integrated surface electromyograms of the three superficial parts of the quadriceps and isokinetic knee extensor maximum torque and power production were recorded simultaneously and at different angular velocities in both legs in 11 male subjects with unilateral tear of the anterior cruciate ligament. The cross-sectional area (CSA) of the thigh and its muscular components were measured by computerized tomography. The principal findings were a small but significant decrease in quadriceps CSA on the affected side; a decreased active, but not passive, range of movement; decreased mechanical output, whether or not corrected for differences in CSA; and decreased electromyographic activity--particularly in rectus femoris. These findings suggest that the reason for the decreased maximum and total knee extensor performance seen in these patients is a change in knee joint receptor afferent inflow.  相似文献   
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