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91.
92.
Three propolis samples from Austria, Germany and France were investigated by GC/MS, where eleven compounds were being new for propolis. The samples showed some similarities in their qualitative composition. Phenylethyl-trans-caffeate, benzyl ferulate and galangin were predominant in German propolis. Benzyl caffeate was predominant in French sample. Pinocembrin was predominant in French and Austrian propolis and trans-p-coumaric acid was predominant in all samples. The antimicrobial activity against Staphylococcus aureus; Escherichia coli, and Candida albicans was evaluated. German propolis showed the highest antimicrobial activity against Staphylococcus aureus and Escherichia coli. While Austrian propolis has the highest activity against Candida albicans. French propolis was effective against all pathogens but less than German and Austrian propolis.  相似文献   
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Dioecism has always been an issue in many plant species with its numerous disadvantages, especially in woody trees such as date palms. As one of the most important crops in the Middle Eastern countries, researchers are having problems identifying of sex of the plant in its early stages of development. Hence, proper population stands in the male: female ratio for maintenance is almost impossible in the field for better production. In this study, sex determination of date palm (Phoenix dactilyfera L.) were identified in regions of the Y chromosome (Date-SRY) gene, the pivotal gene that initiates sex determination, using a new technique and thus an economically desirable objective, which will significantly impact profits in seed based cultivations. Partial sequences of the Date-SRY were taken and amplified by nested polymerase chain reaction (PCR). According to the results, the exact sex of date palm was identified in all the tested plants, while amplified regions of the Date-SRY gene closely matched with the human and papaya sequences. In addition, a primer pair was designed to amplify the sequences of the SRY-date gene with confidence that it will identify male date palms. These primer sequences include SRY-date Forward 5′- cggccctctaagtatctgtgcgcaacg-3′ (SRY-date F) and the SRY-date Reverse 5′- gtttgcacttcgaagcagag-3′ (SRY-date R). The complete sequence of the DNA has been registered and deposited in GenBank (BankIt1598036 DPSRY1 KC577225 thenKJ873056).  相似文献   
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Background  

The mammalian protein kinase TLK1 is a homologue of Tousled, a gene involved in flower development in Arabidopsis thaliana. The function of TLK1 is not well known, although knockout of the gene in Drosophila or expression of a dominant negative mutant in mouse cells causes loss of nuclear divisions and missegregation of chromosomes probably, due to alterations in chromatin remodeling capacity. Overexpression of TLK1B, a spliced variant of the TLK1 mRNA, in a model mouse cell line increases it's resistance to ionizing radiation (IR) or the radiomimetic drug doxorubicin, also likely due to changes in chromatin remodeling. TLK1B is translationally regulated by the availability of the translation factor eIF4E, and its synthesis is activated by IR. The reason for this mechanism of regulation is likely to provide a rapid means of promoting repair of DSBs. TLK1B specifically phosphorylates histone H3 and Asf1, likely resulting in changes in chromatin structure, particularly at double strand breaks (DSB) sites.  相似文献   
97.

Objective

Rheumatoid arthritis (RA) is one of the most prevalent chronic autoimmune diseases; it typically involves the hands, wrists, ankles, and eventually all joints. Some studies have reported that zinc serum levels are lower in patients with RA than in healthy individuals.

Materials and Methods

Seventy-nine patients with RAwere selected. The patients were all less than 75 years old and were diagnosed by a rheumatologist. Serum zinc levels were measured using the flame photometry method with a blood sample of 5 mL. The relationship between the average serum zinc level and disease activity was analyzed based on the DAS28 scoring scale for different RA groups. The significance threshold was set at p<0.05. Data analyses were implemented in SPSS 22.0.

Results

There was a significant inverse relationship between the serum zinc levels and disease activity. Chi-square tests were used to compare zinc serum levels with respect to disease activity. There were significant differences in zinc levels among three groups of patients with different levels of disease severity, such that disease activity increased as the serum zinc level decreased (p<0.001).

Conclusion

There was a significant inverse relationship between the serum zinc level and RA activity based on the DAS28 score. Therefore, it is recommended that mineral deficiencies should be addressed by optimizing the zinc supply along with other standard medications in order to reduce RA activity.
  相似文献   
98.
Insect-resistant transgenic cotton has been commercialized for two decades. Most of the introduced cultivars express Bt gene(s) constitutively under the control of 35S promoter in whole-plant tissues. However, there have been other promoters considered by researchers to confine the toxin expression to targeted organ and tissues. We developed a triple-gene construct including GNA, cry1Ac and cp4 epsps genes. We attempted to confine cry1Ac expression to insect biting sites by cloning it to downstream of a wound-inducible promoter isolated from Asparagus officinalis (AoPR1). Moreover, to broaden the range of resistance, GNA was driven by the 35S promoter to target the sap-sucking insects like aphids which impose large losses in cotton production. To select the transformants in selection medium and for glyphosate tolerance, GNA and cry1Ac genes were accompanied with cp4 epsps gene. Two binary vectors harboring desired genes were constructed and utilized in the study (pGTGNAoC1AC and pGTGN35C1AC). Transformation of cultivar GSN-12 was carried out by employing Agrobacterium tumefaciens strain EHA105. Plantlets were primarily screened under glyphosate (N-phosphonomethyl glycine) selection pressure and subsequently subjected to molecular and biotoxicity assays. Introduction of cry1Ac and GNA to cotton plant conferred resistance to Spodoptera littoralis and Aphis gossypii Glover. Restriction of cry1Ac toxin protein to insect biting sites along with a plant lectin attributes significantly to insect pest management strategies.  相似文献   
99.
BACKGROUND: An imbalance between zinc and copper metabolism has been reported to predispose to coronary artery disease (CAD) in Western populations, but there are little data for other racial groups. We have therefore investigated the association between serum copper and zinc, and CAD in Iranian subjects undergoing coronary angiography. METHODS: Serum copper, zinc, fasting lipid profile, and blood glucose levels were measured in 114 patients (67 male and 47 female) undergoing routine coronary angiogram. Anthropometric features including blood pressure were determined using standard procedures. Demographic characteristics, including menopausal status and smoking habit, were assessed by questionnaire. RESULTS: Male patients had lower serum copper (p<0.05), lower serum zinc (p<0.05), and higher serum zinc/copper ratio (p<0.05) than females. Serum copper and zinc concentrations were significantly lower in the subjects with angiographically defined CAD than those patients with a normal angiogram, although the zinc/copper ratio was higher in these patients (p<0.001). Serum copper (r=-0.303, p<0.001) and zinc (r=-0.250, p<0.01) concentrations were both inversely related to age, and copper was positively associated with fasting serum triglycerides (r=0.188, p<0.05). CONCLUSION: Serum copper and zinc concentrations were significantly lower in Iranian patients with abnormal versus those with a normal angiogram. However, the zinc/copper ratio was higher in patients with CAD compared to subjects without CAD. Serum zinc and copper concentrations appear to be influenced by several physiological factors including age and gender.  相似文献   
100.
The distribution of zinc between soil pools was measured over 48 weeks in grassed and bare soils using selective extractants. Although changes in the extractable fractions of zinc occurred in all soils, they tended to be less in the bare soils. From weeks 18 to 48 the rate of uptake of zinc by ryegrass ranged from 3.4 to 106 g Zn/week in the 5 soils studied. The CaCl2-extractable Zn in the soil increased over the 48 weeks, while the amount of acetic acid-, EDTA-and oxalate-extractable Zn decreased. Superimposed on these changes was the effect of growing ryegrass. There was relatively more CaCl2-Zn, but less acetic acid-Zn and oxalate-Zn, in the grassed soil compared to the bare soil. There was no significant change over time in the difference in the EDTA-Zn pool between grassed and ungrassed soils. Comparison of zinc taken up by the ryegrass and zinc lost to soil, measured by oxalate extraction, suggested that selective extraction was not a good measure of zinc uptake by grass.  相似文献   
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