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11.
Fundamental processes influencing human growth can be revealed by studying extreme short stature. Using genetic linkage analysis, we find that biallelic loss-of-function mutations in the centrosomal pericentrin (PCNT) gene on chromosome 21q22.3 cause microcephalic osteodysplastic primordial dwarfism type II (MOPD II) in 25 patients. Adults with this rare inherited condition have an average height of 100 centimeters and a brain size comparable to that of a 3-month-old baby, but are of near-normal intelligence. Absence of PCNT results in disorganized mitotic spindles and missegregation of chromosomes. Mutations in related genes are known to cause primary microcephaly (MCPH1, CDK5RAP2, ASPM, and CENPJ).  相似文献   
12.
Biological activity tests were performed on alpha-galactoside preparations obtained from Lupinus angustifolius L. cv. Mirela (alkaloid-rich) and Pisum sativum L. cv. Opal seeds. The studies included the following tests: acute toxicity, cytotoxic test, delayed type hypersensitivity (DTH), plaque-forming cell number (IgM-PFC), and influence on the growth of bifidobacteria and coliform presence in rat colon. Results of these studies showed that alpha-galactosides from lupin and pea seeds were essentially nontoxic. Their acute toxicity (LD(50)) in mice was >4000 mg kg(-1) of body weight. alpha-galactoside preparations were not cytotoxic for mouse thymocytes in vitro. The in vitro test shows that oligosaccharides from lupin and pea are utilized by selected beneficial colon bacterium strains. The in vivo experiment demonstrated that alpha-galactosides from legume significantly influenced the growth of bifidobacteria in rats colon. Simultaneously, the decrease of the coliform presence was observed. The chemical composition of the tested preparations had no significant effect on their biological activity.  相似文献   
13.
Climate and soil conditions in South Florida along with an extensive canal system facilitate movement of agricultural pesticides into surface waters. In a two-year study (2002-2004) of the currently used pesticides in South Florida, atrazine, endosulfan, metolachlor, chlorpyrifos, and chlorothalonil were the most frequently detected in the canals and in Biscayne Bay, with average concentrations of 16, 11, 9.0, 2.6, and 6.0 ng/L, respectively. Concentrations of atrazine and chlorpyrifos were highest near corn production. Chlorothalonil and endosulfan concentrations were highest near vegetable production, with no clear trend for metolachlor, which is used on multiple crops. Concentration data were used to calculate an aquatic life hazard potential for the planting period (November) versus the harvest period (March). This analysis indicated that a higher hazard potential occurs during harvest, primarily from the use of endosulfan. These data will also serve to document canal conditions prior to implementation of the Comprehensive Everglades Restoration Plan (CERP).  相似文献   
14.
European Journal of Forest Research - Pterocarya fraxinifolia, native to the southern Caucasus and adjacent areas, has been widely introduced in Europe. In this study, we investigate the following:...  相似文献   
15.
The studies conducted in 2003–2004 focused on the possibilities of applying a tannic solution to remove adhesiveness from pikeperch eggs. Spawners were caught in Lake P?tnowskie (central Poland) and then transported to the Gos?awice Fish Farm. After initial selection, the fish were weighed, measured and stimulated with human chorionic gonadotropin. Gametes were obtained 5 days after the first injection. The weight and diameter of the eggs, and the commercial fecundity of individual females were determined. The eggs were fertilized with the dry method. After the addition of water, the eggs were mixed for 4 min, and then divided into 20 g portions. After determining the number of eggs in the various portions, the adhesiveness removal procedure was performed. Three concentrations of tannic acid solution (500, 1000, 1500 mg L?1) and three exposure times (0.5, 2, 5 min) were applied. The eggs were incubated in Weiss jars. The studies indicated that both the solution concentration and the exposure time significantly (P<0.05) impacted pikeperch egg hardening, the degree of adhesive removal and embryo survival. The tannic acid solution concentration of ≤500 mg L?1 applied for 0.5–2 min was not effective; the eggs clumped and it was impossible to separate them even with intensive mixing. Better results were obtained using higher tannic acid concentrations and/or by lengthening exposure time. The adhesiveness of pikeperch eggs disappeared completely after 5 min exposure to tannic acid solution concentrations of 500–1500 mg L?1 or after 2 min exposure to solution concentrations of 1000–1500 mg L?1. In these variants, the embryo survival rate to the eyed‐egg stage was 78.0–84.0% (2003) and 82.3–84.7% (2004). However, high tannic acid concentration had a negative impact on the pikeperch larvae hatching. The greatest decrease in survival rate was observed in groups exposed to a tannic acid solution of 1500 mg L?1 for 2 and 5 min periods. Thus, the optimum method for removing pikeperch egg adhesiveness was to apply a solution of tannic acid at a concentration of 500 mg L?1 for 5 min or 1000 mg L?1 for 2–5 min.  相似文献   
16.

• Introduction, Material and Methods  

The genetic structure and diversity of ten natural populations of Juniperus phoenicea L. from the western part of the species range have been studied using random amplified polymorphic DNA (RAPD) markers.  相似文献   
17.
The aim of the study was to analyze the factors creating consumer attributes of roasted beef steaks of various animals. Eight cuts from 30 carcasses (characterized by various types of animal, conformation and fat class, rib fat thickness, ossification score) were selected. Samples were prepared using the roasting method and consumers rated the tenderness, juiciness, flavor, overall acceptability (rated in a 100‐point scale), and satisfaction (rated from 2 to 5) for analyzed samples. No influence of type of animal, fat class, conformation class or ossification score on the results of consumer analysis was observed. For all analyzed factors, the influence of cut on consumer analysis was observed (the highest values of all consumer attributes were observed for tenderloin ‐ for juiciness significantly higher than for other cuts, for tenderness, flavor and MQ4 comparable only with rump (RMP231), while for overall acceptability and satisfaction – with both rump cuts). For rib fat thickness consumer attributes of roasted beef meat were not linear, but the influence was observed – the highest values of consumer attributes were observed for 13 mm rib fat thickness.  相似文献   
18.
Reactions of three Polish potato cultivars to potato virus S (PVS) were investigated at 22°C. Cultivars Tajfun and Tonacja exhibited partial resistance with systemic infection detected in some inoculated plants; cultivar Bryza was susceptible to PVS with systemic infection detected in all inoculated plants. The virus was not detectable by ELISA at 23 days postinoculation (dpi) but was detected after 40 dpi. Infection rate and viral accumulation were significantly lower in Tonacja and Tajfun than in Bryza, but no statistically significant difference between Tajfun and Tonacja was detected. Both susceptible and resistant genotypes displayed various, either common or cultivar-specific, symptoms. Delayed systemic infection at 56 dpi was observed in some cases in Tonacja and Tajfun. Resistance-related alteration of a set of miRNAs and mRNA targets in the tested cultivars in response to PVS at 22°C exhibited inter- and intracultivar variability. The majority of tested genes were altered only in the partially resistant Tajfun and Tonacja but not in the susceptible Bryza. Enhanced expression of AGO1-2, DCL1, stu-miR482 and its target Gpa2 was observed in Tonacja and plants of Tajfun in which PVS was detected, with the highest induction of Gpa2 in Tajfun (30.2-fold). However, their expression remained unchanged or decreased in plants of Tajfun in which PVS was undetected. Increased expression of stu-miR168a and stu-miR172e was observed in Tonacja and the PVS-undetected plants of Tajfun, respectively, but not in the PVS-detected plants of Tajfun. This is the first report on cultivar-specific alteration of miRNA in a potato–PVS resistance interaction.  相似文献   
19.
Subunits of high molecular weight glutenins strongly influence wheat bread making quality and can be associated with important agronomic traits. Polish winter wheats show a significant quantitative dominance of the null allele over the coding alleles of the Glu-A1 locus. To identify the causes of such skewed distribution, 116 F5 lines obtained from six cross combinations were analyzed for their HMW glutenin subunits and 11 agronomic characteristics, such as plant height and uniformity, leaf blotch and leaf rust resistance, grain yield per plot, number of grains per ear, grain yield per ear, 1000 kernel weight, frost tolerance, total protein content and the SDS-sedimentation value. The SDS-sedimentation value, resistance to leaf blotch and frost tolerance showed statistically significant associations with the status of the Glu-A1 locus. It appears that chromosome 1A with the null allele at Glu-A1 carries a closely linked locus responsible for frost tolerance. With early strong selection for winter hardiness, the null allele of Glu-A1 becomes fixed in advanced breeding materials despite its strong negative impact on the end use quality.  相似文献   
20.
Purpose

Technological progress and high market demand contributed to a significant interest in the production of fertilizers based on humic acids. The aim of this study was to evaluate the possibilities of using humic acids obtained from lignite in the production of new commercial products. For this purpose, it is necessary to determine the quality standard requirements for such material. Properties of humic acids depend on source of origin as well as method of its extraction.

Materials and methods

The humic acids were extracted from polish deposit of lignite–Sieniawa Lubuska by alkaline extraction using for this purpose six kinds of extractants: 0.1 M NaOH and 0.25 M NaOH, 0.1 M KOH and 0.25 M KOH, and 0.1 M Na4P2O7 and 0.25 M Na4P2O7. The humic samples were used in solid powder form and characterized by UV-Vis spectroscopy, 13C NMR spectroscopy, fluorescence spectroscopy, and thermal analysis.

Results and discussion

The determining factor influencing a degree of humic acids extraction from lignite and their structure is type of extractant. The largest efficiency of extraction (about 50%) was obtained with the use of NaOH solutions. All examined humic acids were generally characterized by simple and heterogeneous molecularly structure with low molecular weight and low aromatic polycondensation. Therefore, it can be concluded that humic acids extracted with NaOH and KOH solutions are less condensed than those extracted with Na4P2O7 solutions. It can suggest that humic acids obtained from lignite using solutions of Na4P2O7 are characterized by a low transformation degree and greater amount of carboxyl groups.

Conclusions

Low rank coal can be successfully used in agriculture as a rich source of humic acids. Reagent used in their extraction, apart from high efficiency should have a neutral impact on their structure. Studies on the physicochemical properties of humic acids can be helpful in predicting behaviors of such fertilizer components in the environment and in inventing new products taking the principles of sustainable development into consideration.

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