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101.
Kizilpinar I Civelek E Tuncer A Dogan C Karabulut E Sahiner UM Yavuz ST Sackesen C 《International journal of biometeorology》2011,55(4):623-631
Pollen plays an important role in the development and exacerbation of allergic diseases. We aimed to investigate the days
with highest counts of the most allergenic pollens and to identify the meteorological factors affecting pollen counts in the
atmosphere of Ankara, Turkey. Airborne pollen measurements were carried out from 2005 to 2008 with a Burkard volumetric 7-day
spore trap. Microscope counts were converted into atmospheric concentrations and expressed as pollen grains/m3. Meteorological parameters were obtained from the State Meteorological Service. All statistical analyses were done with pollen
counts obtained from March to October for each year. The percentages of tree, grass and weed pollens were 72.1% (n = 24,923), 12.8% (n = 4,433) and 15.1% (n = 5,219), respectively. The Pinaceae family from tree taxa (39% to 57%) and the Chenopodiaceae/Amaranthaceae family from weed taxa, contributed the highest percentage of pollen (25% to 43%), while from the grass taxa, only the Poaceae family was detected from 2005 to 2008. Poaceae and Chenopodiaceae/Amaranthaceae families, which are the most allergenic pollens, were found in high numbers from May to August in Ankara. In multiple logistic
regression analysis, wind speed (OR = 1.18, CI95% = 1.02–1.36, P = 0.023) for tree pollen, daily mean temperature (OR = 1.10, CI95% = 1.04–1.17, P = 0.001) and sunshine hours (OR = 1.15, CI95% = 1.01–1.30, P = 0.033) for grass pollen, and sunshine hours (OR = 3.79, CI95% = 1.03–13.92, P = 0.044) for weed pollen were found as significant risk factors for high pollen count. The pollen calendar and its association
with meteorological factors depend mainly on daily temperature, sunshine hours and wind speed, which may help draw the attention
of physicians and allergic patients to days with high pollen counts. 相似文献
102.
Improved nitrogen nutrition enhances root uptake, root-to-shoot translocation and remobilization of zinc ((65) Zn) in wheat 总被引:4,自引:0,他引:4
This study focussed on the effect of increasing nitrogen (N) supply on root uptake and root-to-shoot translocation of zinc (Zn) as well as retranslocation of foliar-applied Zn in durum wheat (Triticum durum). Nutrient solution experiments were conducted to examine the root uptake and root-to-shoot translocation of (65) Zn in seedlings precultured with different N supplies. In additional experiments, the effect of varied N nutrition on retranslocation of foliar-applied (65) Zn was tested at both the vegetative and generative stages. When N supply was increased, the (65) Zn uptake by roots was enhanced by up to threefold and the (65) Zn translocation from roots to shoots increased by up to eightfold, while plant growth was affected to a much smaller degree. Retranslocation of (65) Zn from old into young leaves and from flag leaves to grains also showed marked positive responses to increasing N supply. The results demonstrate that the N-nutritional status of wheat affects major steps in the route of Zn from the growth medium to the grain, including its uptake, xylem transport and remobilization via phloem. Thus, N is a critical player in the uptake and accumulation of Zn in plants, which deserves special attention in biofortification of food crops with Zn. 相似文献
103.
The aim of this study was to determine the changes caused by physical stress on the body composition of young males. In order to show these changes, the study was performed with 104 young male laborers who worked through their adolescence and who were currently working in workshops in the industrial sector (Group 1, mean age 18.48 +/- 0.61 years). For the control group, two groups of the same age but having a difference in terms of socioeconomic status were chosen. The first one of these was comprised of individuals who had the same socioeconomic status as the laborers (Group 2, n = 102, mean age 18.39 +/- 0.58 years) but were not laborers. The second control group was composed of individuals from the higher socioeconomic levels of society (Group 3, n = 103, mean age 18.43 +/- 0.67). Measurements of the height of the individuals were taken with a standard portable anthropometer, and their body weight and BIA measurements were taken with Tanita TBF-305 leg-to-leg body composition analysis equipment. The results of the analysis show that the weight, height, BMI and fat mass values of the laborers were significantly lower (P < 0.05-0.001) than those of Group 3, but were not statistically different from those of Group 2. These findings reveal that the effects of socioeconomic conditions on body composition outweigh those of working conditions. 相似文献
104.
105.
Oxidative stress is considered to be involved in the pathophysiology of all cancers. The aim of this study is to examine oxidative stress and antioxidant status in patients with breast cancer by evaluation of the serum levels of total antioxidant capacity (TAC) and lipid peroxidation products as malondialdehyde (MDA) and lipid hydroperoxide and to investigate the relationship between these parameters, oxidative stress and serum lipids and lipoproteins. In our study, serum TAC, MDA, lipid hydroperoxide, HDL-cholesterol, VLDL-cholesterol, LDL-cholesterol, total cholesterol, triacylglycerol (TAG), albumin and uric acid levels of 56-breast cancer patients in different clinical stages and 18 healthy women were determined. Significantly lower-levels of TAC were detected in patients with breast cancer in comparison to controls (2.01 +/- 0.01 mmol/l and 2.07 +/- 0.03 mmol/l, respectively, p < 0.05). Serum MDA levels of the patients were higher compared to the controls (3.64 +/- 0.25 microM and 2.72 +/- 0.22 microM, respectively, p < 0.05). No significant difference between lipid hydroperoxide levels of patients and controls was found (0.33 +/- 0.05 microM and 0.32 +/- 0.01 microM, respectively, p > 0.05). These data show that lower TAC and higher MDA levels i.e. increased oxidative stress may be related to breast cancer. 相似文献
106.
Zeybek U Yaylim I Yilmaz H Ağaçhan B Ergen A Arikan S Bayrak S Isbir T 《Cell biochemistry and function》2007,25(4):419-422
This study was designed to investigate, in the Turkish population, an association of methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism and the risk of gastric and colorectal cancer. Our study was carried out in 35 patients with gastric cancer (20 men, 15 women) and 144 controls (75 men, 69 women) and 52 colorectal cancer (31 men, 21 women). MTHFR C677T genotypes were determined by polymerase chain reaction, restriction fragment length polymorphism techniques. No differences were observed in the distribution of MTHFR genotypes or allele frequencies in cases versus controls. The homozygous mutation (T/T) in the MTHFR gene was identified in 14.3% of gastric cancer versus 10.4% of controls. MTHFR C677T frequencies of the CC, CT and TT genotypes among colorectal cancer patients were 34.6%, 51.9% and 13.5%, respectively. MTHFR C677T polymorphism may not be important in an individual's susceptibility to gastric and colorectal cancer in Turkey and may not be a useful marker for identifying patients at high risk of developing gastric and colorectal cancer. 相似文献
107.
Polat Derya Genc Durmaz Yasar Konar Nevzat Pirouzian Haniyeh Rasouli Toker Omer Said Palabiyik Ibrahim Tasan Murat 《Journal of applied phycology》2022,34(1):375-383
Journal of Applied Phycology - In this study, dried or encapsulated Nannochloropsis oculata microalgal biomass was used in spread samples (0.00–0.75 g (100 g)?1... 相似文献
108.
Mohamad I. Nugraha Hyunho Kim Bin Sun Saheena Desai F. Pelayo Garcia de Arquer Edward H. Sargent Husam N. Alshareef Derya Baran 《Liver Transplantation》2019,9(28)
Colloidal quantum dots (CQDs) are attractive materials for thermoelectric applications due to their simple and low‐cost processing; advantageously, they also offer low thermal conductivity and high Seebeck coefficient. To date, the majority of CQD thermoelectric films reported upon have been p‐type, while only a few reports are available on n‐type films. High‐performing n‐ and p‐type films are essential for thermoelectric generators (TEGs) with large output voltage and power. Here, high‐thermoelectric‐performance n‐type CQD films are reported and showcased in high‐performance all‐CQD TEGs. By engineering the electronic coupling in the films, a thorough removal of insulating ligands is achieved and this is combined with excellent surface trap passivation. This enables a high thermoelectric power factor of 24 µW m?1 K?2, superior to previously reported n‐type lead chalcogenide CQD films operating near room temperature (<1 µW m?1 K?2). As a result, an all‐CQD film TEG with a large output voltage of 0.25 V and a power density of 0.63 W m?2 at ?T = 50 K is demonstrated, which represents an over fourfold enhancement to previously reported p‐type only CQD TEGs. 相似文献
109.
Mohamad I. Nugraha Hyunho Kim Bin Sun Md Azimul Haque Francisco Pelayo Garcia de Arquer Diego Rosas Villalva Abdulrahman El‐Labban Edward H. Sargent Husam N. Alshareef Derya Baran 《Liver Transplantation》2019,9(13)
Colloidal quantum dots (CQDs) are demonstrated to be promising materials to realize high‐performance thermoelectrics owing to their low thermal conductivity. The most studied CQD films, however, are using long ligands that require high processing and operation temperature (>400 °C) to achieve optimum thermoelectric performance. Here the thermoelectric properties of CQD films cross‐linked using short ligands that allow strong inter‐QD coupling are reported. Using the ligands, p‐type thermoelectric solids are demonstrated with a high Seebeck coefficient and power factor of 400 μV K?1 and 30 µW m?1 K?2, respectively, leading to maximum ZT of 0.02 at a lower measurement temperature (<400 K) and lower processing temperature (<300 °C). These ligands further reduce the annealing temperature to 175 °C, significantly increasing the Seebeck coefficient of the CQD films to 580 μV K?1. This high Seebeck coefficient with a superior ZT near room temperature compared to previously reported high temperature‐annealed CQD films is ascribed to the smaller grain size, which enables the retainment of quantum confinement and significantly increases the hole effective mass in the films. This study provides a pathway to approach quantum confinement for achieving a high Seebeck coefficient yet strong inter‐QD coupling, which offers a step toward low‐temperature‐processed high‐performance thermoelectric generators. 相似文献
110.