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161.
The present study aimed at analysing the content of fluorine (F), calcium (Ca) and magnesium (Mg) in the hair of young male students (n?=?52) of a secondary school in Mafinga in Tanzania (Africa) who participated in anthropological examinations. Ca and Mg concentrations were determined using atomic absorption spectrophotometer while F levels using a potentiometric method. F in the hair of boys from older group (≥16 years old; n?=?24) was significantly higher than in the younger group (<16 years old; n?=?28) versus Ca and Mg levels. High carbohydrate diet was predominant—mainly based on corn or bean and meat served once a week, with few fruit and raw vegetables. Collective catering in the dormitory reflected habits and culinary preferences at home. The lack of balanced diet, with majority of the nutritional energy supplied by easily accessible and cheap carbohydrates, was reflected in dietary deficiencies, characterised, among others, by visible skin conditions and tooth decay.  相似文献   
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Plant Cell, Tissue and Organ Culture (PCTOC) - The morphogenic callus (MC) of Fagopyrum tataricum contains a large amount of flavonoids, especially rutin, and exhibits a high level of antioxidant...  相似文献   
165.

This is the first study to generate carrot plants for enhanced salinity tolerance using a single-cell in vitro system. Protoplasts of three carrot accessions were exposed to treatment by seven different concentrations of NaCl (10–400 mM). Salt concentrations higher than 50 mM decreased plating efficiency and those of 200–400 mM of NaCl completely arrested mitotic divisions of cultured cells. The protoplast-derived plants from the control and 50–100 mM NaCl treatment were subjected to an 8-week salt stress in greenhouse conditions induced by salinized soil (EC 3 and 6 mS cm?1). 50 mM NaCl stress applied in vitro induced polyploidy among regenerated plants. The regenerants obtained from the 50 and 100 mM NaCl-treated protoplast cultures grown in saline soil had a higher survival rate compared to the regenerants from the control cultures. The salt-stressed plants accumulated anthocyanins in petioles and produced denser hairs on leaves and petioles in comparison to the control plants. Salt stress influenced pollen viability and seed setting of obtained regenerants. The results suggest that salt stress applied in vitro in protoplast cultures creates variation which allows alleviating the negative effects of salt stress on the development and reproduction of the carrot.

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166.
Summary Trypsin inhibitor SFTI-1 isolated from sunflower seeds (comprising 14 amino acid residues and two cycles: head-to-tail cyclisation and disulfide bridge) is the smallest naturally occurring plant serine proteinase inhibitor. In our recent paper we have shown that the elimination head-to-tail cyclisation did not change trypsin inhibitory activity as judged by measured by association equilibrium constants K a . The removal of disulfide bridge produced 2.4-fold lower activity. In the present paper we described chymotrypsin inhibitory activity. SFTI-1 inhibits significantly lower bovine α-chymortypsin (K a =(5.20±1.56)×106 M−1). The activity of the analogue with disulfide bridge only was practically the same, whereas the K a value determined for homodetic peptide was almost 3-fold lower. Considering the results obtained and the recent literature data we postulate the lower inhibitory activity against both enzymes of the analogue with head-to-tail cyclisation only reflect its lower proteolytic stability.  相似文献   
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INTRODUCTION: Obese patients may have abnormal calcium homeostasis because of unbalanced diet and decreased sun exposure. Bariatric surgery itself may lead to disturbances in calcium homeostasis (and in consequence changes in bone mass) or increase preexisting metabolic derangements. The aim of the study was: 1. To assess calcium homeostasis and biochemical markers of bone turnover in patients with morbid obesity. 2. To determine the impact of bariatric surgery on parameters mentioned above. 3. To establish recommendations for supplementation with calcium and vitamin D in morbidly obese patients after bariatric surgery. MATERIAL AND METHODS: Serum calcium, parathormone (PTH), vitamin D (25(OH)D), biochemical markers of bone turnover (beta-CrossLaps as a marker of bone resorption and osteocalcin as a marker of bone formation) and urine calcium as well as fat mass, lean mass and bone mineral content (by DXA) were measured before bariatric surgery of the stomach (VBG or GBP) in 57 morbidly obese patients (48 women, 9 men; mean age 35.9 y). The same procedures were repeated six months after operation in 28 of them (24 women, 4 men). Daily calcium intake was also determined based on food questionnaire. RESULTS: Biochemical findings in the group of patients before bariatric surgery were as follows: serum calcium, beta-CrossLaps and urine calcium were within normal range, PTH concentration was increased to 81.0 pg/ml and 25(OH)D as well as osteocalcin concentration decreased (4.9 ng/ml and 13.6 ng/ml, respectively). Six months after bariatric surgery there was no change in serum and urine calcium, PTH concentration decreased to normal level (46.8 pg/ml), 25(OH)D concentration increased to 6.5 ng/ml (not significant) and still remained below normal range. Markers of bone turnover--both resorption and formation--increased (beta-CrossLaps over normal range to 0.594 ng/ml, osteocalcin to normal range 26.8 ng/ml). Daily calcium intake was below RDA before and after bariatric procedure. CONCLUSIONS: 1. Patients with morbid obesity have secondary hyperparathyroidism and deficiency of vitamin D. 2. Abrupt weight loss after bariatric surgery is accompanied by the regression of secondary hyperparathyroidism, decrease of the deficiency of vitamin D and increase in bone turnover. 3. Supplementation with vitamin D and calcium is recommended for patients with morbid obesity after bariatric surgery.  相似文献   
168.
The induction of thymocyte apoptosis through the Nur77-mediated intrinsic pathway can be of physiological importance in the clonal deletion of autoreactive thymocytes during negative selection in the thymus and/or in thymocytes undergoing oncogenic transformation. Ionomycin treatment induces endogenous Nur77 expression as well as apoptosis and cytochrome c release in thymocytes. Here it is shown for the first time that in normal thymocytes undergoing apoptosis, ionomycin induces translocation of endogenous Nur77 not only to the nucleus, but also to mitochondria. Immunosuppressant FK506 inhibits Nur77 NBRE and NurRE binding activity but has no effect on thymocytes apoptosis, the subcellular localization of Nur77, or cytochrome c release. This indicates that thymocytes can undergo apoptosis through the intrinsic Nur77-mediated mitochondrial pathway and that the transactivation activity of Nur77 monomers or dimers is not necessary for thymocyte apoptosis.  相似文献   
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American ginseng (Panax quinquefolium L.) is a perennial medicinal herb originally grown in Canada and USA, and recently also in China, Australia, Holland and Poland. Several commercial preparations are produced from ginseng roots, that are known for their antifatigue, antitumor, antistress and immune system stimulating functions. The medicinal properties are due mainly to the active components – ginsenosides. In this work, the results of field cultivation experiments are presented that examine the effects of foliar application of several growth regulators on quality parameters and ginsenoside content of P. quinuefolium roots. The growth regulators tested, i.e., kinetin, daminozide, mixture of gibberellic acid (GA3) with potassium salt of α-naphthalene acetic acid (kNAA) and new preparation – IPO-1 – benzimidazole derivative (obtained from the Institute of Organic Industry in Warsaw – at present during the process of patent), were applied at a concentration of 100 or 200 mg l−1 in the middle of June in the 2nd year of vegetation. After 4 years of cultivation, the roots were dug up and dried, and subsequently the quantitative analysis of individual saponins (Rb1, Rb2, Rc, Rd, Re, Rg1) by HPLC was performed. Growth regulators significantly affected quality parameters, morphological features and accumulation of individual and total ginsenosides in ginseng roots. Regardless of doses, the plant roots treated with growth regulators had a higher content of total ginsenosides in comparison to the control. The growth regulators also affected individual ginsenosides level and narrowed the ratio of Rb:Rg group. The application of kinetin, daminozide and benzimidazole derivative for foliar spray during 2nd year of American ginseng vegetation caused a significant increase in air dry weight of roots and aboveground parts whereas the mixture of GA3 and kNAA showed a decreasing effect. An increase of roots size was observed using higher doses (200 mg l−1) of kinetin and daminozide while a decreasing tendency appeared with the application of the other preparations.  相似文献   
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