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101.
102.
The toxicity of iron, copper, and zinc was studied in soybean seeds of the NE 3297 variety irradiated at different dosages of gamma rays. After cultivating in plastic boxes for 14 days, the average plant heights, fresh weight, and chlorophyll content decreased in inverse proportion to radiation dose. As the radiation dose increased, the concentrations of iron, copper, zinc, soluble protein, and malondialdehyde increased, but the activities of superoxide dismutase and peroxidase enzymes activities were significantly decreased. The activities and the number of the superoxide dismutase isoenzymes also varied depending on the irradiation dosages.  相似文献   
103.
To analyse working conditions and to provide information about the degree to which shoe workers are exposed to n-hexane, the urinary excretion of total 2,5-hexanedione (2,5-HD) was determined in 81 employees in 12 shoe factories. Twenty-five individuals who had experienced no exposure to solvents were used as controls. 2,5-HD was measured in spot urine samples collected from workers at the end of shift. In the urine of shoe workers, the 2,5-HD presented a mean value of 2.33 mg g-1 creatinine, a median of 1.96 mg g-1 creatinine. The mean 2,5-HD concentration in the urine samples from non-exposed subjects was 0.28 mg g-1 creatinine, the median value was 0.18 mg g-1 creatinine. The mean time-weighted average (TWA) concentration of n-hexane in 12 shoe workshops was 126.1 ppm, ranging from 23 to 215 ppm. We found a significant, but low, correlation (r = 0.40; p < 0.001) between TWA intensity of environmental exposure to n-hexane and the concentration of 2,5-HD in urine. The probable effect of toluene on the concentration of 2,5-HD was also discussed in the present study.  相似文献   
104.

Background

The aim of the present work was to examine the role of UV-C irradiation on the production of secondary metabolites (total phenolic, total flavanols, total flavonols, catechin, ferulic acid and trans-resveratrol in phenolic compounds and α-, β-, γ- δ-tocopherols) in callus cultures. Studies on the effects of UV-C treatment on callus culture are seldom and generally focused on UV-B. However UV-C radiation play an important role in accumule secondary metabolites.

Results

In this study, callus cultures from Öküzgözü grape cultivar were initiated from leaf petiole explants. Calli formed after 6 weeks on the medium supplemented with 0.5 mg L-1 benzylaminopurine (BA), 0.5 mg L-1 indole acetic acid (IAA) on B5 media. Callus tissues were exposed to UV-C irradiation at 10, 20 and 30 cm distances from the UV source for 5 and 10 minutes and samples were collected at hours 0, 24 and 48.

Conclusions

The greatest total phenolic content (155.14 mg 100 g-1) was detected in calli exposed to UV-C for 5 min from 30 cm distance and sampled after 24 h. 24 h and 48 h incubation times, 30 cm and 5 min were the most appropriate combination of UV-C application in total flavanol content. Maximum total flavonol content (7.12 mg 100 g-1) was obtained on 0 h, 5 min and 20 cm combination. The highest (+)- catechin accumulation (8.89 mg g-1) was found in calli with 10 min UV-C application from 30 cm distance and sampled after 48 h. Ferulic acid content increased 6 fold in Öküzgözü callus cultures (31.37 μg g-1) compared to the control group. The greatest trans-resveratrol content (8.43 μg g-1) was detected in calli exposed to UV-C for 5 min from 30 cm distance and sampled after 24 h. The highest α-tocopherol concentration was found in calli exposed to UV-C for 10 min from 30 cm distance and sampled after 24 h. As a conclusion, it was showed that UV-C radiation had remarkable promoting effects on the accumulation of secondary metabolites in the calli of Öküzgözü grape cultivar.  相似文献   
105.
Acute pancreatitis (AP) is an acute inflammatory condition that results from the digestion of pancreatic tissue by its own enzymes released from the acinar cells. The objective of this study was to investigate the effects of resveratrol on oxidative damage, pro-inflammatory cytokines, and tissue injury involved with AP induced in a rat model using sodium taurocholate (n?=?60). There were three treatment groups with 20 rats per group. Groups I and II received 3 % sodium taurocholate solution, while group III underwent the same surgical procedure yet did not receive sodium taurocholate. In addition, group II received 30 mg/kg resveratrol solution. Rats were sacrificed at 2, 6, 12, and 24 h time points following the induction of AP. Blood and pancreatic tissue samples were collected and subjected to biochemical assays, Western blot assays, and histopathologic evaluations. Resveratrol did not reduce trypsin levels and prevent tissue damage. Resveratrol prevented IκB degradation (except for 6 h) and decreased nuclear factor-κB (NF-κB), activator protein-1 (AP-1) (except for 24 h), and levels of TNF-α, IL-6 (except for 24 h), and iNOS in the pancreatic tissue at all time points (P?<?0.05). Serum nitric oxide (NO) levels were reduced as well (P?<?0.05). Thus, we concluded that resveratrol did not reduce trypsin levels and did not prevent tissue injury despite the reduction in oxidative damage and pro-inflammatory cytokine levels detected in this model of AP.  相似文献   
106.

Breast cancer is a heterogeneous disease, which is the most common malignancy in women. The incidence and mortality rates of breast cancer indicate that it is the leading cause of cancer-related with deaths. circRNAs operate as part of competing endogenous RNAs (ceRNAs) mechanisms, which play critical roles in the different biological processes of breast cancer such as proliferation, migration, and apoptosis. The goal of the present study is to identify the potential predictive biomarker for breast cancer diagnosis in the circRNA network by in vitro and in silico analyzes. 40 miRNAs were obtained from the miRWalk database and their combinatorial target genes (potential ceRNAs) were identified with ComiR. We stated that the cancer-specific circRNA genes in MCF-7 cells using the cancer-specific circRNA (CSDC) database, and obtained the ones showing potential ceRNA activity in our previous analysis among them. Identified genes with remarkable expression differences between BCa and normal breast tissue were determined by the GEPIA database. Moreover, the Spearman correlation test in the GEPIA database was used for the statistical analysis of the relationship between DCAF7 and SOGA1, SOGA1 and AVL 9, DCAF7 and AVL 9 gene pairs. And also, DCAF7, SOGA1, and AVL9 gene expression levels were detected in MCF-7 and MCF-10A cells by RT-qPCR method. DCAF7, SOGA1, and AVL9 gene were significantly more expressed to BCa tissue and MCF-7 cells than normal breast tissue and MCF-10 A cells. And also, DCAF7 and SOGA1, SOGA1 and AVL9, DCAF7 and AVL9 genes pairs were found to be significantly correlated with BCa. These genes may be considered as potential predictive biomarkers to discriminate BCa patients from healthy persons. Our preliminary results can supply a new perspective for in vitro and vivo studies in the future.

  相似文献   
107.
The physical properities of sea turtle nesting beaches may strongly influence embryo development and hence conservation planning. In this study, we compared the characteristics of two nesting beaches of Green Turtles, Chelonia mydas, at Akyatan and Samanda? in southern Turkey. A total of 48 sand samples from 48 nests was examined and compared in respect to moisture content (M), temperature (TT), electrical conductivity (EC), salinity (S), total dissolved solution (TDS), pH, air ratio (AR), sand grain size together with distance from sea (DFS), depth (ND), incubation period (ID) and hatching success. Significant differences between the two areas were found in nest chamber moisture, conductivity, salinity, total dissolved solution and sand grain size. In a principal component analysis (PCA), the first component explained 45.1% of the variability and was dominated by the effects of the TDS, EC, S, pH and M. The second component explained 24.2 % of the variation and was dominated by the contributions of the TT, ID and ND. This is evidence that moisture plays a more important role than thermal properties in differentiating between the two beaches.  相似文献   
108.
Pollen morphology of four Matricaria species and 28 Tripleurospermum species was investigated with light microscopies (LM) and scanning electron microscopies (SEM). Pollen slides were prepared using Wodehouse technique. Measurements were based on 20 or more pollen grains per specimen. For SEM studies, dried pollen grains were transferred on aluminum stubs and coated with gold for 4 min in a sputter-coater. The pollen grains of Matricaria and Tripleurospermum are radially symmetric and isopolar. The pollen grains of the Matricaria are oblate-spheroidal with the polar axes 16.6–31.2 μm and the equatorial axes 18.7–23.9 μm. Tripleurospermum is oblate-spheroidal, suboblate and prolate-spheroidal with the polar axes 15.6–32.2 μm and the equatorial axes 17.7-38.5 μm. The pollen grains of Tripleurospermum are operculate and tricolporate. Matricaria is operculate and usually tricolporate or rarely syncolporate, tricolpate and tetracolporate. The pollen grain of both taxa shows echinate ornamentation. The spines are commonly conical with a broadened base and a tapered apical portion. The spine length varies between 1.8–4 μm in Tripleurospermum and 2.3–3.3 μm in Matricaria. The width of spines varies between 2.8–4.6 μm in Tripleurospermum and 2.4–3.6 μm in Matricaria. Inter-spinal area shows granulate–perforate, reticulate–perforate, rugulate–perforate ornamentations and the tectum surrounding the spine base is micro perforate. Overall exine thickness ranges from 2.8 to 4.8 μm in Tripleurospermum, 3.6 to 5.2 μm in Matricaria. Intine is thicker under pores in Tripleurospermum (0.3–0.62 μm) than in Matricaria (0.6–0.8 μm). Inter-spinal ornamentations, pollen shape and the numbers of perforations at the spin base have been observed as important morphological characters.  相似文献   
109.
110.

Background

In successfully negotiating the Framework Convention on Tobacco Control (FCTC), the World Health Organization (WHO) has led a significant innovation in global health governance, helping to transform international tobacco control. This article provides the first comprehensive review of the diverse campaign initiated by transnational tobacco corporations (TTCs) to try to undermine the proposed convention.

Methods and Findings

The article is primarily based on an analysis of internal tobacco industry documents made public through litigation, triangulated with data from official documentation relating to the FCTC process and websites of relevant organisations. It is also informed by a comprehensive review of previous studies concerning tobacco industry efforts to influence the FCTC. The findings demonstrate that the industry''s strategic response to the proposed WHO convention was two-fold. First, arguments and frames were developed to challenge the FCTC, including: claiming there would be damaging economic consequences; depicting tobacco control as an agenda promoted by high-income countries; alleging the treaty conflicted with trade agreements, “good governance,” and national sovereignty; questioning WHO''s mandate; claiming the FCTC would set a precedent for issues beyond tobacco; and presenting corporate social responsibility (CSR) as an alternative. Second, multiple tactics were employed to promote and increase the impact of these arguments, including: directly targeting FCTC delegations and relevant political actors, enlisting diverse allies (e.g., mass media outlets and scientists), and using stakeholder consultation to delay decisions and secure industry participation.

Conclusions

TTCs'' efforts to undermine the FCTC were comprehensive, demonstrating the global application of tactics that TTCs have previously been found to have employed nationally and further included arguments against the FCTC as a key initiative in global health governance. Awareness of these strategies can help guard against industry efforts to disrupt the implementation of the FCTC and support the development of future, comparable initiatives in global health. Please see later in the article for the Editors'' Summary  相似文献   
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