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101.
A clinical trial was undertaken to investigate the effects of Eleutherococcus senticosus (ES) and Panax ginseng (PG) on competitive club-level endurance athletes engaged in their normal in-season training. Participants were matched for training stress and received a 33% ethanolic extract (8 mL/day) containing either ES, PG (equivalent to 4 g and 2 g/day of dried root, respectively), or a placebo. A pre-test and post-test were used to evaluate the effects of six weeks of supplementation on cortisol, testosterone, and testosterone to cortisol ratio (TCR) as well as circulating numbers of total T-cells, T-helper cells (CD4), T-suppressor cells (CD8), CD4 to CD8 ratio, natural killer cells, and B lymphocytes. None of the immune system variables changed significantly nor showed any clear trend from pre to post test in any of the treatment groups. No significant change in testosterone, cortisol or TCR was observed in the PG group. In the ES group, however, TCR decreased by 28.7% from 0.0464 to 0.0331 (P=0.03). The main contribution to this decrease appeared to be a non-significant (P= 0.07) 31% trend towards increased cortisol rather than a very small non-significant (P = 0.36) 7% decrease in the calculated mean for testosterone. This result suggested that contrary to initial expectation, ES increased rather than decreased hormonal indices of stress, which may be consistent with animal research suggesting a threshold of stress below which ES increases the stress response and above which ES decreases the stress response.  相似文献   
102.
Previous studies on hypothyroid subjects have indicated serious psychiatric symptoms affecting the patients' quality of life. The present prospective cross-sectional study's aim was to examine these symptoms in thyroid patients with different functional states. A total of 254 patients (age: 56 +/- 14 years [mean +/- standard deviation], 181 female, 73 male) referred to a hospital for radioiodine treatment of hyperthyroidism or for follow-up of differentiated thyroid cancer, respectively, were included. All patients underwent the twelve-item general health questionnaire, which is an instrument for detecting mood disturbances. Euthyroid and hyperthyroid patients did not differ significantly in their general health questionnaire score (11 +/- 5 vs. 11 +/- 7), nor did subclinical hyperthyroid (11 +/- 6) or subclinical hypothyroid subjects (12 +/- 5). In contrast, hypothyroid patients showed a significantly higher mean score (17 +/- 7, p < 0.001, ANOVA). Binary logistic regression revealed that hypothyroidism increases age and gender-adjusted risk for critical mood deterioration by seven-fold. Thus, hypothyroidism represents a widely underestimated functional condition that may severely affect mental health.  相似文献   
103.
104.
Calli were initiated from flower buds, gynoecia and inflorescence segments of Haworthia magnifica v. Poelln. and subcultured on solid medium. Two liquid culture steps were necessary to prepare the calli for the isolation of protoplasts capable of sustained cell divisions. Plants were regenerated from protoplast-derived calli. The influence of both the osmolality of the culture media and exudates on the viability of protoplasts and protoplast-derived cell colonies is briefly discussed.  相似文献   
105.
106.
A particulate translation system isolated from the yeast Saccharomyces cerevisiae was shown to translate faithfully in-vitro-transcribed mRNA coding for a mating hormone precursor (prepro-alpha-factor mRNA) and to N-glycosylate the primary translation product after its translocation into the lumen of the microsomal vesicles. Glycosylation of its three potential sugar attachment sites was found to be competitively inhibited by acceptor peptides containing the consensus sequence Asn-Xaa-Thr, supporting the view that the glycan chains are N-glycosidically attached to the prepro-alpha-factor polypeptide. The accumulation in the presence of acceptor peptides of a membrane-specific, unglycosylated translation product (pp-alpha-F0) differing in molecular mass from a cytosolically located, protease-K-sensitive alpha-factor polypeptide (pp-alpha-Fcyt) by about 1.3 kDa, suggests that, in contrast to previous reports, a signal sequence is cleaved from the mating hormone precursor on/after translocation. This conclusion is supported by the observation that the multiply glycosylated alpha-factor precursor is cleaved by endoglucosaminidase H to a product with a molecular mass smaller than the primary translation product pp-alpha-Fcyt but larger than the membrane-specific pp-alpha-F0. Translation and glycosylation experiments carried out in the presence of various glycosidase inhibitors (e.g. 1-deoxynojirimycin, N-methyl-1-deoxynojirimyin and 1-deoxymannojirimycin) indicate that the N-linked oligosaccharide chains of the glycosylated prepro-alpha-factor species are extensively processed under the in vitro conditions of translation. From the specificity of the glycosidase inhibitors applied and the differences in the molecular mass of the glycosylated translation products generated in their presence, we conclude that the glycosylation-competent microsomes contain trimming enzymes, most likely glucosidase I, glucosidase II and a trimming mannosidase, which process the prepro-alpha-factor glycans down to the (Man)8(GlcNAc)2 stage. Furthermore, several arguments strongly suggest that these three enzymes, which apparently represent the full array of trimming activities in yeast, are exclusively located in the lumen of microsomal vesicles derived from endoplasmic reticulum membranes.  相似文献   
107.
Summary The receptor lymph of campaniform sensilla on the halteres of the blowfly, Calliphora vicina, was analyzed histochemically. Acid mucopolysaccharides were demonstrated by a test for iron-binding capacity (Hale-reaction). Further characterization by enzyme treatment showed that the receptor lymph contains hyaluronic acid and/or chondroitin sulfate. Ultrahistochemical studies gave evidence for glycoproteins in the inner and outer receptor lymph space. The significance of acid mucopolysaccharides for arthropod sensilla is discussed.  相似文献   
108.
E Tüchsen  C Woodward 《Biochemistry》1987,26(25):8073-8078
Hydrogen-deuterium exchange is measured for the buried primary amide groups of Asn-43 and Asn-44 in bovine pancreatic trypsin inhibitor. Amide protons trans and cis to the amide carbonyl oxygen (HE and HZ, respectively) exchange at indistinguishable rates. Uncorrelated exchange of HE and HZ is established for both residues by following the nuclear Overhauser enhancement from HE to HZ during the deuterium exchange. The exchange of Asn-43 and Asn-44 side-chain protons differs qualitatively from exchange of primary amide groups in fully solvated model compounds, for which HE generally exchanges faster than HZ. The equal rates for the buried primary amide HE and HZ in BPTI are not a consequence of coupled exchange. The data indicate rapid rotation around the CO-NH2 bond for both Asn-43 and Asn-44 and suggest considerable lability of intramolecular hydrogen bonds. The side chain of Asn-43 has all of its polar atoms integrated into the very stable hydrogen-bonded structure of the protein. Asn-44 is hydrogen-bonded to side chains and to a buried water molecule. Solvent isotope exchange is several orders of magnitude more restricted by protein secondary and tertiary structure than the CO-NH2 rotation, indicating that N delta H2 groups flip many times before hydrogen isotope exchange occurs.  相似文献   
109.
The N-terminal part of the lipoprotein from the outer membrane of Escherichia coli, tripalmitoyl-S-glyceryl-L-Cys-Ser and analogs with longer sequences, are polyclonal activators for B-lymphocytes. Triple-chain lipopeptides also constitute efficient low-molecular-weight carrier/adjuvant systems, which can be linked to antigens to yield immunogens for antibody production without further additives. This is the first report of monolayer experiments with chemically well defined, synthetic lipopeptide mitogens with the composition of the N-terminus of an important bacterial membrane protein. Various derivatives of the lipoprotein N-terminus were synthesized. These lipopeptides differed in the length of the peptide moiety, the number of fatty acid residues, and protective groups. In order to obtain the surface areas for the lipopeptides in isotherms and hysteresis isotherms, monolayer experiments with a computer-controlled film balance were performed. To get some information about the interaction of these compounds with typical membrane lipids mixed monolayers were formed from triple-chain lipopeptides with dipalmitoylphosphatidylcholine and cholesterol. A comparison of the mitogenic response of the compounds was made in an in vitro system with B-lymphocytes from Balb/c mice.  相似文献   
110.
Bactopterin is a novel pterin occurring in bacterial molybdoenzymes as the organic portion of the molybdenum cofactor. Its structure is investigated here. The compound contains a single pterin ring and carries a side chain at carbon atom 6 of the pterin nucleus as indicated by the formation of pterin-6-carboxylic acid upon alkaline permanganate oxidation. Studies with phosphate-cleaving enzymes revealed the presence of two monophosphoric acid monoesters. The affinity of reduced bactopterin for thiol-Sepharose points to the presence of thiol(s) in active bactopterin.  相似文献   
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