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Fifteen middle-aged, untrained (defined as no regular exercise) men (mean age 49.9 years, range 42-67) cycled on a cycle ergometer at 50 rpm for 30 min at an intensity producing 60% predicted maximum heart rate [(fc,max), where fc,max = 220 - age]. Total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) and triglyceride (Tg) concentrations were measured from fasting fingertip capillary blood samples collected at rest, after 15 and 30 min of exercise, and at 15 min post-exercise. The mean HDL-C level increased significantly from the resting level of 0.85 mmol.l-1 to 0.97 mmol.l-1 (P < 0.05) after 15 min of exercise, increased further to 1.08 mmol.l-1 (P < 0.01) after 30 min of exercise and remained elevated at 1.07 mmol.l-1 (P < 0.01) at 15 min post-exercise. These increases represented changes above the mean resting level of 14.1%, 27.1% and 25.9% respectively. The HDL-C/LDL-C ratio increased significantly from a resting ratio of 0.20 to 0.26 after 30 min of exercise (P < 0.01) and to 0.24 at 15 min post-exercise (P < 0.05). The mean Tg level increased significantly from a resting level of 0.88 mmol.l-1 to 1.05 mmol.l-1 after 15 min, and to 1.06 mmol.l-1 after 30 min of exercise (P < 0.05 at each time). The TC/HDL-C ratio decreased significantly (P = 0.05) after 30 min of exercise and at 15 min post-exercise by 18.8% and 14%, respectively. No significant changes were observed in the levels of TC or LDL-C over time.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
3.
The 13C-n.m.r. spectra of asialo-GM1 and GM1-oligosaccharide are completely assigned and compared to those previously found for intact GM1 and for the series GM4, GM3, GM2, GM1, GD1a, GD1b, and GT1b. Removal of the ceramide residue from GM1 liberated a free, reducing aldehyde group, which was reflected in a doubling of the 13C-n.m.r. signals assignable to the d-glucose residue because of α,β equilibrium. The spectrum of asialo-GM1 lacks the resonances from the sialic acid residue, as expected; in addition, several resonances from the neutral gangliotetraglycosyl residue shifted to different field positions after removal of sialic acid from GM1. These resonances include that of C-4 of the inner β-d-galactosyl residue, and C-1 of the 2-acetamido-2-deoxy-d-galactosyl residue that is near the site of attachment of the sialosyl residue. The differences between the chemical shifts of the carbon resonances of oligomeric and monomeric saccharides, termed linkage shifts, provide a quantitative assignment aid. They are ~ 13 of those for residues linked to sialic acid than those for residues linked to the neutral hexose chain. Correlations among linkage shifts for pairs of glycosidically-linked carbon atoms for asialo-GM1 and GM1-oligosaccharide were compared with those for the series of gangliosides GM4 to GT1b, and differences are noted for resonances for carbon atoms near the sialic acid residue. The spectrum of ganglioside GM1b, a positional isomer of GM1 whose 13C-n.m.r. spectrum has not yet been observed, is predicted.  相似文献   
4.
Patterns of hair distribution of the front of the human neck are recognized. The basic patterns are supraclavicular, suprasternal and supraclaviculosuprasternal. They are correlated with the types of chest hair distribution.  相似文献   
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Mutants of the Drosophila miniature-dusky (m-dy) gene complex display morphogenetic phenotypes (miniature or dusky) caused by a change in the size and/or shape of the epidermal cells comprising the adult wing. In addition to a dusky phenotype, certain Andante-type mutants also exhibit lengthened circadian periods for two different behavioral rhythms. If the latter phenotype results from a direct effect on the circadian pacemaker, the Andante function should be required within the brain. In order to define the tissues that require the morphogenetic and behavioral functions, we have carried out a genetic mosaic analysis. This study demonstrates that normal wing morphogenesis is entirely dependent on the genotype of wing cells. Furthermore, temperature-shift experiments with a temperature-sensitive dy mutant indicate that the morphogenetic function is required during adult development, and after the cessation of wing epidermal cell proliferation. At this time in development, a columnar epithelium in the developing wing becomes flattened into the mature wing blade, and we postulate that the cell-size defect of m-dy mutants results from an alteration of this mor-phogenetic process. In contrast to the wing mor-phogenesis phenotype, the characterization of locomotor activity in mosaic adults revealed a strong correlation between the head genotype and the Andante circadian-period phenotype. This result indicates that neural tissues mediate the rhythm function. Thus, the behavioral and morphogenetic functions require gene expression in distinct tissues. Furthermore, the behavioral results are consistent with a requirement for Andante function within circadian pacemaker neurons. © 1995 Wiley-Liss, Inc.  相似文献   
6.
The central nervous system effects of bombesin on cardiovascular function were examined in conscious, freely-moving rats. Intracerebroventricular administration of bombesin elevated mean arterial pressure, reduced heart rate and inhibited cold-induced tachycardia. Adrenalectomy prevented bombesin-induced elevations of mean arterial pressure. In contrast, bombesin-induced bradycardia was neither adrenal-dependent nor a baroreceptor-mediated reflex response to increased arterial pressure. Systemic atropine methyl nitrate treatment attenuated bombesin-induced bradycardia, suggesting that bombesin acts within the central nervous system to stimulate cardiac vagal activity.  相似文献   
7.
We have generated three hybridomas producing rat monoclonal antibodies to a surface antigen, ThB, that is shared by murine B lymphocytes and approximately 50 percent of murine thymocytes. These antibodies, produced by immunizations with MOPC-104E cells, appear to recognize the same antigen that was previously detected by rabbit and goat antisera to MOPC-104E cells (Yutoku et al. 1974, Yutoku et al. 1976).Using these antibodies, we have studied a genetic polymorphism that is associated with the level of ThB expression on B lymphocytes but not with the antigen's expression on thymocytes. We present evidence that this trait is controlled by one gene,Thb, which we find to be very closely linked to the gene or genes controlling the Ly-6, Ly-8, DAG, and Ala 1 antigen(s). While the latter four antigens were described as markers on mature T (or activated T and B) lymphocytes, ThB is restricted to immature thymocytes and all B cells. ThB is not expressed on kidney, although some investigators (McKenzie et al. 1977 a, Halloran et al. 1978) report Ly-6 expression on that tissue. SJL/J, C57BL/10JHz, DBA/2J, and AKR/J are among the mouse strains carrying theThb h allele, while BALB/cN, CBA/J, C3H.SW/SnHz, and A/J carry theThb l allele. The ThB antigen has not yet been identified as a glycoprotein after cell-surface iodination, NP-40 solubilization, and immunoprecipitation.This work was supported in part by grants from the National Institutes of Health (AI-08917, CA-04681, GM-17367).  相似文献   
8.
Summary Many species of Eucalyptus, one of the dominant genera in Australian forests and woodlands, contain high levels of tannins and other phenols and are also heavily damaged by grazing insects. These phenols do not appear to affect insect attack because a wide range of concentrations of condensed tannins and other phenols in leaves of 13 Eucalyptus sp. influenced neither feeding rates of Paropsis atomaria larvae, nor their nitrogen use efficiencies. We discuss reasons why tannins may not appreciably reduce the availability of nitrogen (N) to these insects. Performance was directly related to leaf N concentration, and growth rates, N gains, and N use efficiencies all increased as leaf N content increased, although absolute feeding rates remained constant. These relationships differ from those found in insects feeding on other plants, and we suggest that the low N contents common in Eucalyptus leaves may be responsble. We propose that the extensive damage observed in many eucalypts is in part related to the high feeding rates maintained by individual larvae.To whom offprint requests shouid be sent  相似文献   
9.
Experiments were undertaken to determine the effect of various chromosome banding treatments on the histone and nonhistone proteins of isolated, fixed, air-dried metaphase chromosomes. Chromosome preparations were exposed to G-banding (SSC, urea, NaCl-urea, or trypsin), R-banding (Earle's balanced salt solution), and C-banding (NaOH or Ba(OH)2) treatments, and the extracted and residual proteins were examined by SDS polyacrylamide gel electrophoresis. The results indicate that each of the banding treatments induce characteristic alterations in the chromosomal proteins. The residual proteins left in chromosomes after the diverse G-banding treatments were generally similar to one another, indicating that treatments inducing the same type of banding have similar effects on the chromosomal proteins. This was also true for the two different C-banding treatments. On the other hand, the residual protein patterns seen after the G-banding treatments were strikingly different from those seen after R-banding, which in turn differed from those seen after C-banding. The treatments inducing different types of banding therefore produce markedly different effects on the chromosomal proteins. These protein alterations may have an important influence on the induction of chromosome bands.  相似文献   
10.
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