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81.
Polyamines (PAs) are related to many physiological processes, including soil drought stress. Two yellow lupin ‘Morocco 4’ (drought tolerant) and ‘Taper’ (drought sensitive) were exposed to soil drought for 2 weeks. The half of the examined plants were additionally sprayed with a solution of polyamine biosynthesis inhibitor—dl-α-difluoromethylarginine (DFMA). Yellow lupin leaves showed a 19% increase and seeds a 54% decrease in the total PA contents. The seeds contained fourfold less PAs than the leaves under drought conditions. The highest amount of spermidine and lack of agmatine were found in the leaves, while in the seeds the highest content of spermine and the presence of agmatine was confirmed. The use of DFMA under drought conditions decreased the content of spermine in ‘Morocco 4’ and ‘Taper’ (41 and 19%, respectively) and spermidine in ‘Taper’ (by 13%), as well as reduced two out of three of the yield components. More tolerant ‘Morocco 4’, after DFMA treatment was characterized by a higher spermidine and spermine content and a smaller decrease in yield components compared to the less tolerant ‘Taper’. Simultaneously subjecting plants to soil drought and DFMA treatment caused in ‘Morocco 4’ a decline in the number of pods and seeds per plant and seeds dry weight per plant (64, 50 and 54%, respectively), while in ‘Taper’ a reduction of the number of pods per plant and seeds per pod (32 and 27%, respectively) was observed. These results confirm that PAs are involved in yellow lupin tolerance and may play a protective function under soil drought conditions.  相似文献   
82.
Osteoarthritis causes the degradation of the articular cartilage and periarticular bones. Trace elements influence the growth, development and condition of the bone tissue. Changes to the mineral composition of the bone tissue can cause degenerative changes and fractures. The aim of the research was to determine the content of cadmium (Cd), nickel (Ni), copper (Cu) and zinc (Zn) in the tibia, the femur and the meniscus in men and women who underwent a knee replacement surgery. Samples were collected from 50 patients, including 36 women and 14 men. The determination of trace elements content were performed by ICP-AES method, using Varian 710-ES. Average concentration in the tissues of the knee joint teeth amounted for cadmium 0.015, nickel 0.60, copper 0.89 and zinc 80.81 mg/kg wet weight. There were statistically significant differences in the content of cadmium, copper and zinc in different parts of the knee joint. There were no statistically significant differences in the content of cadmium, nickel, copper and zinc in women and men in the examined parts of the knee joint. Among the elements tested, copper and nickel showed a high content in the connective tissue (the meniscus) compared to the bone tissue (the tibia and the femur).  相似文献   
83.
In 66 patients with peptic ulcer (11 with gastric ulcer, 55 with duodenal ulcer, 19 women, 47 men) the serum concentrations of prolactin, dehydrocholic acid and gastrin were determined. The studies were repeated after treatment with ranitidine: in 50 patients after three weeks and in 40 patients after another 30 days. During the first period ranitidine 2 x 150 mg was administered, while during the second period the dose was 1 x 150 mg. The results were compared with those obtained from 120 healthy subjects. Before starting the treatment prolactin levels were significantly higher than those in the control group. During the treatment a significant decrease of the levels was observed. Similar changes of prolactin concentrations were found in the group of 39 men with duodenal ulcer isolated from the studied patients, who were compared with a group of 50 healthy men. It was not found that the development of peptic ulcer and the treatment with ranitidine exerted and effect on the changes of gastrin and dehydrocholic acid concentrations.  相似文献   
84.
85.
The objective of the study was to compare the level of dissatisfaction with body image of men and women of the social elite in the Wielkopolska region, Poland, in the light of anthropometric indicators.  相似文献   
86.
Seven new trypsin inhibitors, CyPTI I–VII, were purified from ripe seeds of Cyclanthera pedata by affinity chromatography on immobilized chymotrypsin in the presence of 5 M NaCl followed by preparative native PAGE at pH 8.9. The CyPTIs (Cyclanthera pedata trypsin inhibitors) belong to a well-known squash inhibitor family. They contain 28–30 amino acids and have molecular weights from 3031 to 3367 Da. All the isolated inhibitors strongly inhibit bovine β-trypsin (Ka > 1011 M− 1) and, more weakly, bovine α-chymotrypsin (Ka ≈ 104–106 M− 1). In the presence of 3 M NaCl the association constants of CyPTIs with α-chymotrypsin increased a few hundred fold. Taking advantage of this phenomenon, a high concentration of NaCl was used to isolate the inhibitors by affinity chromatography on immobilized chymotrypsin. It was found that although one of them, CyPTI IV, had split the Asn25–Gly26 peptide bond, its inhibitory activity remained unchanged. The hydrolyzed bond is located downstream of the reactive site. Presumably, the inhibitor is a naturally occurring, double-chain protein arising during posttranslational modifications.  相似文献   
87.
Abstract

As a part of the research aimed on identification of new nucleobase derivatives with improved biological properties, a series of novel 8-substituted acyclovir derivatives were synthesized. The 8-azidoguanosine 4 and novel 8-azidoacyclovir 9 were synthesized from commercially available guanosine 1 and acyclovir 6 which were transformed into 8-bromopurine derivatives 2 and 7 and hydrazine derivatives 3 and 8, respectively. 8-Triazolylguanosine 5 and 8-triazolylacyclovir analogs 1012 were successfully synthesized via the Cu(I) catalyzed 1,3-dipolar cycloaddition reaction of azides 4 and 9 with propargyl alcohol, 4-pentyn-1-ol and 5-hexyn-1-ol. The novel 1,4-disubstituted 1,2,3-triazolyl compounds 5, 1012 were evaluated for antiviral activity against selected DNA and RNA viruses and cytostatic activity against normal Madine Darby canine kidney (MDCK I) cells, and seven tumor cell lines (HeLa, CaCo-2, NCI-H358, Jurkat, K562, Raji and HuT78). While tested compounds exerted no antiviral activity at nontoxic concentrations, the 8-triazolyl acyclovir derivative 10, with the shortest alkyl substituent at the C-4 of triazole ring, was found to be the most active against the CaCo-2 cell line.  相似文献   
88.
Summary The Bcl family contains both pro and antiapoptotic proteins participating in the regulation of neuronal cell death in several pathological conditions. However, very little is known about physiological profiles of Bcl-2/Bax expression in normal brain. In this study, we examined expression profile of Bcl-2 and Bax proteins in normal pineal gland in children. The material for analysis was obtained by biopsy of pineal parenchyma during surgery of pineal cysts. All specimens were labeled immunohistochemically and analyzed by means of confocal laser scanning microscope. We found only few Bcl-2 expressing (0.7%) and no Bax-immunopositive (0.0%) pinealocytes. Bcl-2-positive cells were mature neurons, neither young ones nor glia.  相似文献   
89.
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   
90.
INTRODUCTION: Studies carried out over the last few years have provided information about the increase in the incidence of type 1 diabetes in different parts of the world including the European countries bordering Poland. THE AIM OF STUDY: The aim of this study was to determine the long-term trends in the incidence of type 1 diabetes over the 20 years between 1980 and 1999 and to compare the incidence during the decades preceding and following the 1989 economic and political transformation in Poland. MATERIAL AND METHODS: The registration of type 1 diabetes among people aged 0-29 was drawn up according to the DERI recommendations using three data sources. We calculated the age-standardised incidence rates for five-year age groups and determined the long-term trend in the incidence of type 1 diabetes in south-eastern Poland. RESULTS: A significant growth in the incidence of type 1 diabetes was observed among people aged 0-29 in the Rzeszów Province in the period between 1980 and 1999. The mean age-standardised incidence rate was 6.1/100,000, and a statistically significant difference was noted between the 1980s and the 1990s (5.3 [95%CI 4.5-6.0] and 6.8 [95%CI 5.9-7.6]). The male incidence of 6.7 significantly exceeded that for females--5.5/100,000. There was also a higher incidence in the group aged 0-14 in comparison with the group aged 15-29 (6.4 and 5.8/100,000 respectively). The highest incidence was found in boys aged 10-14 (11.5/100,000) and a significantly rising trend was observed in children of 0-4 years old. CONCLUSIONS: The mean incidence of type 1 diabetes among the study population was low. Nevertheless, we demonstrated a significantly increasing trend in the incidence during the 20-year observation period. The incidence in the 1990s, both in general and for males, was significantly higher when compared to the 1980s.  相似文献   
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