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71.
Picea omorika plants were regenerated from embryo and seedling shoot tip cultures. Adventitious and axillary shoots were produced on 1/2 MS medium containing benzyladenine and kinetin. Benzyladenine was more effective in bud induction, whereas kinetin hastened shoot development. Excised shoots were elongated on 1/3 MS medium without growth regulators, multiplied with kinetin and rooted with or without indole-3-butyric acid.Abbreviations BA N6-benzyladenine - 2IP N 6-(2-isopenteny) adenine - NAA -naphthaleneacetic acid - IAA indole-3-acetic acid - IBA indole-3-butyric acid  相似文献   
72.
We investigated the effects of high pressure treatment on green plant leaves of two species, red rose (Rosa rubiginosa L.) and silver birch male (Betula pendula Roth). Both species were treated with pressure up to 100 bar in order to explore stress reactions, including desirable or undesirable metabolites in plant. When increasing the pressure, chlorophyll (Chl) fluorescence maximum shifts to the wavelength of about 680 nm for both red rose and silver birch, with shift rates–0.062 nm/bar and–0.082 nm/bar, respectively. High pressure induces the changes of the position for the second fluorescence maximum at approximately 730 nm in both species with the same shift rate–0.083 nm/bar. When increasing pressure the change of the photosynthetic apparatus efficiency decreases for both plant species slowly and nonlinearly. High-pressure treatments irreversibly damaged the leaf tissue and at this way induced changes of Chl fluorescence and photosynthetic efficiency.  相似文献   
73.
74.
The aim of our study was to determine the activity of antioxidant defence (AD) enzymes: superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), glutathione reductase (GR) and the phase II biotransformation enzyme glutathione-S-transferase (GST) in the hepatopancreas, the gills and muscle of Spiny cheek crayfish (Orconectes limosus) from the River Danube and to compare tissue specificities of investigated enzymes. Our results indicated that both specific and total SOD activities in the hepatopancreas were lower compared to the gills and muscle. Total SOD activity in the gills was lower with respect to that in muscle. CAT and GSH-Px (both specific and total) activities were higher in the hepatopancreas compared to those in the gills and muscle. In the gills the specific and total GR activities were higher than in the hepatopancreas and muscle. The specific and total GST activities were higher in the hepatopancreas compared with the gills and muscle. Our study represents the first comprehensive report of AD enzymes in tissues of O. limosus caught in the River Danube. The noted tissue distributions of the investigated AD enzyme activities most likely reflected different metabolic activities and different responses to environmental conditions in the examined tissues.  相似文献   
75.
The aim of this paper was to evaluate the ocular findings in patients with chronic renal failure (CRF) undergoing haemodialysis (HD). In 64 patients undergoing haemodialysis (30 female and 34 male), aged 24-83 years (mean 58 years) on haemodialysis 1-213 months (mean 47 months) complete ocular examination were performed: visual acuity (VA), intraocular pressure (IOP), biomicroscopic examination and fundoscopy. On right eye sixty-nine percent of patents had VA 0.6 or better, and on left eye 84% of patients had VA 0.6 or better. Mean IOP before dialysis was 15 mmHg and after dialysis was 14 mmHg. In 9 patients (14%) we found corneo-conjunctival calcium deposits. No correlation of ocular calcification and parathyroid hormone (PTH) level or calcium and phosphate product were observed. 39 (60%) patients had cataract. Hypertensive vascular changes were seen in 44 (68%) patients and in 6 (7%) patients age-related macular degeneration. Seven patients had diabetes mellitus and in 5 diabetic retinopathy was observed. Patients with CRF or who are receiving HD represent unique group of patients. Pathologic change could be found in many tissue and organs, therefore we suggest ocular examination more frequently in dialysis patients.  相似文献   
76.
The present study compares the results of three different covalent immobilization methods employed for immobilization of lipase from Candida rugosa on Eupergit® C supports with respect to enzyme loadings, activities and coupling yields. It seems that method yielding the highest activity retention of 43.3% is based on coupling lipase via its carbohydrate moiety previously modified by periodate oxidation. Study of thermal deactivation kinetics at three temperatures (37, 50 and 75 °C) revealed that the immobilization method also produces an appreciable stabilization of the biocatalyst, changing its thermal deactivation profile. By comparison of the t1/2 values obtained at 75 °C, it can be concluded that the lipase immobilized via carbohydrate moiety was almost 2-fold more stable than conventionally immobilized one and 18-fold than free lipase. The immobilization procedure developed is quite simple, and easily reproduced, and provides a promising solution for application of lipase in aqueous and microaqueous reaction system.  相似文献   
77.
The total number of 542 patients with colorectal cancer surgery have been analyzed in order to estimate the effect of receiving transfusion local recurrences, and the disease free - survival. It should be examined whether there are changes in general immunity indicators which would be connected with perioperative transfusion. A significant connection has been found between local recurrences and blood transfusion (p<0.0001), the most noticeable being in Dukes A (p =0.045), localization on rectum (p=0.036). The receiving of blood transfusion is linked significantly with disease free - survival reduction (p =0.0068; log rank), the most significant being in Dukes A stage (p =0.0123; log rank) and with localization on rectum (p=0.0231). The analysis of general immunity indicators has shown significant immunocompromitation of patients just before the surgery and this could have effect on immunomodulation caused by transfusion and just as on the treatment prognosis of colorectal carcinoma.  相似文献   
78.
A biomarker of aluminium accumulation in the human body can play a valuable role in determining health effects of chronic aluminium exposure, complementing other human and environmental monitoring data. In vivo neutron activation provides such a non-invasive biomarker. To date, the best in vivo neutron activation system used thermalised neutrons from a nuclear reactor at Brookhaven National Laboratory, which suffered only slightly from interference from other elements, primarily phosphorus, and from the disadvantage of restricted accessibility. At McMaster, we use a nuclear reaction on an accelerator to select neutron energy, which eliminates the interferences. Spectral decomposition analysis improved sensitivity. A new 4pi detection system also enhanced sensitivity. Together these improvements yield a minimum detection limit of 0.24 mgAl in a hand, slightly better than at Brookhaven and equivalent to "normal" levels. Further improvements should result from a new irradiation cavity and from using a higher proton current on the accelerator to shorten irradiation times. The system is now ready for pilot human studies.  相似文献   
79.
Here we report, for the first time, the results of detailed GC and GC/MS analyses of the essential oil of a rare taxon in Serbia, Hypericum elegans Stephan ex Willd . One hundred and sixty two constituents identified accounted for 98.6% of the oil. The major components of the oil were undecane (31.9%), α‐pinene (16.7%), nonane (6.1%), bicyclogermacrene (5.8%), 2‐methyloctane (3.7%), and germacrene D (3.6%). Non‐terpenoids as chemotaxonomic markers constituted the main fraction of H. elegans oil, whereby n‐alkanes were the most abundant contributors of this fraction. Based on these results and previously published ones, we performed an intrasectional multivariate statistical comparison of corresponding essential‐oil chemical compositions. Principal component analysis (PCA) and agglomerative hierarchical clustering (AHC) of the data on the volatile profiles of section Hypericum taxa revealed that H. elegans either represents an oil chemotype of its own (AHC) or could be considered related to H. perforatum (PCA).  相似文献   
80.
Subscapular skinfold, elbow breadth and upper arm indicators of nutritional status were studied in the population of Dalmatia in Croatia. Age- and sex-specific percentiles were obtained from 4373 subjects, 18 to 74 years of age, and compared to the U.S. NHANES I and II reference data. There were significant differences between these data sets in all studied variables. The results complement those reported previously for BMI and triceps skinfold and indicate that high prevalence of overweight in Dalmatians largely reflects their muscularity and skeletal robustness rather than excess body fatness. The findings suggest that the U.S. upper percentiles of BMI and skinfolds are inadequate for the assessment of excess body fatness in Dalmatian population. The obtained population-specific percentile distributions should be used provisionally as the reference data for group comparisons in the Dalmatian region.  相似文献   
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