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51.
52.
H Hahn von Dorsche 《Anatomischer Anzeiger》1984,155(1-5):95-113
The presence of biorhythms in the endocrine organs (pituitary gland, adrenal gland, thyroid gland, islet organ, gonades , and kidney) are reviewed. Biorhythms ( circadian and circannual rhythms) have an influence on the action of this organs. The acrophases of the hormones in the serum have different peaks and their time-correlation is different. The importance of this data for experiments and for the clinical practice is discussed. 相似文献
53.
This study was designed to determine whether the somatostatin analogue,
octreotide, could prevent embryonic loss by normalizing increased uterine
insulin-like growth factor-I (IGF-I) action related to hyperoestrogenaemia
following superovulation. Superovulated immature and
oestradiol-17beta-treated adult rats were infused with 100 or 300 microg/ml
of octreotide respectively, or injected daily with 1 or 10 microg of
octreotide from day 1 to day 3 of pregnancy. On day 3, embryos were
collected from the oviducts and uteri. Uterine luminal fluid was subjected
to embryo culture. The amounts of uterine IGF-I and IGF binding proteins
(IGFBP) were determined by radioimmunoassay and ligand binding assay
respectively. Octreotide infusion normalized uterine IGF-I action following
superovulatory and oestradiol-17beta treatment, by reducing IGF-I
concentrations and increasing IGFBP concentrations. Octreotide infusion
increased the number of normal embryos by 2.7-fold and 1.7-fold in
superovulated and oestradiol-17beta- treated rats respectively, and
reversed the detrimental effects of uterine luminal fluid on embryonic
development caused by superovulatory and oestradiol-17beta treatment. Daily
injections with octreotide had similar but reduced effects in all
parameters examined in both treatment groups. In conclusion, octreotide may
reduce embryonic loss, at least in part, by normalizing IGF-I action
following superovulation.
相似文献
54.
55.
Roberts AD Clark SA Townsend NE Anderson ME Gore CJ Hahn AG 《European journal of applied physiology》2003,88(4-5):390-395
Nineteen well-trained cyclists (14 males and 5 females, mean initial V˙O2max 62.3 ml kg–1 min–1) completed a multistage cycle ergometer test to determine maximal mean power output in 4 min (MMPO4min), maximal oxygen uptake (V˙O2max) and maximal accumulated oxygen deficit (MAOD). The athletes were divided into three groups, each of which completed 5, 10
or 15 days of both a control condition (C) and live high:train low altitude exposure (LHTL). The C groups lived and trained
at the ambient altitude of 610 m. The LHTL groups spent 8–10 h night–1 in normobaric hypoxia at a simulated altitude of 2,650 m, and trained at the ambient altitude of 610 m. The changes to MMPO4min, V˙O2max and MAOD in response to LHTL altitude exposure were not significantly different for the 5-, 10- and 15-day treatment periods.
For the pooled data from all three treatment periods, there were significant increases in MMPO4min [mean (SD) 5.15 (0.83) W kg–1 vs 5.34 (0.78) W kg–1] and MAOD [50.1 (14.2) ml kg–1 vs 54.9 (13.1) ml kg–1] in the LHTL athletes between pre- and post-altitude exposure. There were no significant changes in MMPO4min [5.09 (0.76) W kg–1 vs 5.16 (0.86) W kg–1] or MAOD [50.5 (14.1) ml kg–1 vs 49.1 (13.0) ml kg–1] in the C athletes over the corresponding period. There were significant increases in V˙O2max in the athletes during both the LHTL [63.2 (9.0) ml kg–1 min–1 vs 64.1 (9.0) ml kg–1 min–1] and C [62.0 (8.6) ml kg–1 min–1 vs 63.4 (9.2) ml kg–1 min–1] conditions. In these athletes, there was no difference in the impact of 5, 10 or 15 days of LHTL on the increases observed
in MMPO4min, V˙O2max or MAOD; and LHTL increased MMPO4min and MAOD more than training at low altitude alone.
Electronic Publication 相似文献
56.
Abstract: A variety of reasons related to the HLA class I system has complicated the application of molecular approaches to HLA class I typing. Here we present a PCR-based HLA-A typing strategy considering the sequence variations of the two most polymorphic exons which allows complete subtyping of the HLA-A locus. The method is based on a sequence-specific amplification identifying the serologically defined HLA-A specificities. The PCR products generated by these group-specific primers bear the sequence information necessary for a postamplification specificity step. The primer pairs are located within one exon, either exon 2 or exon 3, which avoids amplification of polymorphic intron sequences allowing subsequent single-strand conformation polymorphism analysis and facilitating direct sequencing. Using this method we investigated 48 cell lines and 153 clinical samples. 23 PCR reactions are performed per individual for the assignment of the serological specificities A1-A80. The reproducibility was 100% in all cell lines and 85 clinical samples typed on two separate occasions. With the exception of 13 out of 231 possible serological combinations all homozygous and heterozygous combinations of A1-A80 can be distinguished by specific amplification patterns. Comparing the PCR based typing results with those of serology in 12% a discrepancy was found. Solid-phase sequencing or SSCP analysis of the group-specific PCR fragments allowed complete subtyping of the HLA-A locus. This strategy can identify all 48 HLA-A alleles based on the sequence variations of the 2nd and 3rd exon. 1128 homozygous and heterozygous allele combinations are possible for the HLA-A locus. Only 4 out of these 1128 allele combinations remained unresolved. 相似文献
57.
Joachim Ktz Mathias Hahn Burkart Philipp Esen A. Bekturov Sarkyt E. Kudaibergenov 《Macromolecular chemistry and physics.》1993,194(2):397-410
Employing polyampholytes (inclusively polybetaines) of different chemical structure containing carboxylic groups and various basic nitrogen functions, homosymplex formation, as well as the competition between homo- and heterosymplex formation on addition of an appropriate polyelectrolyte, was investigated in dependence of pH and ionic strength by means of viscometry and turbidimetry. With most, but not with all, of the polyampholytes, the expected viscosity minimum at the isoelectric point, with its steepness depending on polyampholyte structure, was observed. Competition of homo- and heterosymplex formation at and near the isoelectric point is mainly governed by the pK values of the species involved, the level of zwitter-ion formation of the polyampholyte and the effect of non-Coulombic interactions, for example, via hydrogen bonds. 相似文献
58.
Sinuhe Hahn Thomas Stalder Marion Wernli Diana Bürgin Jürg Tschopp Shigekazu Nagata Peter Erb 《European journal of immunology》1995,25(9):2679-2685
Fas was recently demonstrated to be the major target molecule engaged by CD4+ cytolytic T lymphocytes (CTL). We examined Fas expression on various cloned T cell subpopulations and their susceptibility to lysis by CD4+ or CD8+ CTL. A reciprocal relationship in Fas and Fas-ligand expression was observed in CD4+ T helper (Th)1- and Th2-type clones, and Fas mRNA was predominantly detected in Th2 clones, whereas Fas-ligand mRNA was principally found in Th1 clones. The two Th0 clones tested expressed both Fas and Fas-ligand, but only one exhibited cytolytic activity, whereas both were sensitive to CD4-mediated lysis. A functional consequence of the inverse Fas-Fas-ligand expression pattern was that Th2 and Th0 cells were sensitive to lysis by both Th1 CD4+ CTL and a CD8+ CTL clone in a Fas-dependent manner. These results suggest that cytolytic CD4+ Th1 cells may play an immunomodulatory role, regulating a Th2/Th0 response by Fas-mediated lysis. 相似文献
59.
C-peptide/C-peptide-like immunoreactivity was shown to be present in the cytoplasm of the soma and the proximal part of apical dendrites of some pyramidal cells in the Neocortex (Gyrus precentralis) and Hippocampus of man. C-peptide (connecting peptide) is a metabolic product in insulin biosynthesis and its localization in neurons is a proof for extrapancreatic insulin production. 相似文献
60.