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61.
Nitric oxide (NO) is a hormone that connects numerous reactions in plant cells under normal and environmental stress conditions. The application of 100 µM NO as sodium nitroprusside (SNP; NO donor) applied individually or in combination with N or S in different combinations (i.e. 100 mg N or S kg−1 soil applied at the time of sowing [100 N + 100S]0d or with split, 50 mg N or S kg−1 soil at the time of sowing and similar dose at 20 d after sowing [50 N + 50S]0d + [50 N + 50S]20d) was tested to alleviate salt stress in mustard (Brassica juncea L.). Application of 100 µM NO plus split application of N and S more significantly promoted stomatal behavior, photosynthetic and growth performance in the absence of salt stress and maximally alleviated effects of salt stress through increased N- and S-use efficiency, proline and antioxidant system. The combined application of N and S at the time of sowing was lesser effective in promoting photosynthesis and growth under salt or no salt stress conditions in presence or absence of NO. The study suggests that salt stress effects on the photosynthetic performance are mitigated more efficiently when NO was applied together with the split application of N and S given at two stages, and the photosynthetic activity was promoted under salt stress through increased N and S assimilation and antioxidant system. This strategy may be adopted in agricultural system for overcoming salt stress effects on performance of mustard.  相似文献   
62.
ABSTRACT

The present study aimed to investigate whether nocturnal melatonin (MEL) ingestion has beneficial effects against exercise-induced oxidative stress and muscle damage in young athletes. Fourteen healthy-trained teenagers performed two-test sessions separated by at least, 1 week. During each session, participants completed the Running-Based Anaerobic Sprint Test (RAST) at 20:00 h. Then, they ingested a single 10-mg tablet of MEL or Placebo (PLA) in a double-blind randomized order at 22:00 h. The following morning (i.e., 07:30 h), participants performed the same test as the previous night. Blood samples were taken before and after exercise. MEL intake increased the peak power (Ppeak) (p < .01), mean power (Pmean) (p < .001) and decreased the total time (TT) (p < .001) and the fatigue index (FI) (p < .05). Furthermore, MEL ingestion attenuated the hematologic parameters before and after exercise (White Blood Cells (WBC: p < .001 and p < .001, respectively); Neutrophiles (NE: p < .001 and p < .001, respectively); Lymphocytes (LY: p < .001 and p < .001, respectively)) and the ultra-sensitive C-reactive protein (us-CRP: p < .001 and p < .001; respectively) compared to PLA. Also, MEL reduced muscle and hepatic damage enzymes before and after exercise (creatine kinase (CK: p < .001 and p < .001; respectively), lactate dehydrogenase (LDH: p < .05 and p < .01; respectively), aspartate aminotransferase (ASAT: p < .01 and p < .001; respectively)), Malondialdehyde (MDA: p < .001 and p < .001; respectively) and Homocysteine (Hcy: p < .001 and p < .001; respectively)) from placebo. Plasma lactate [La] and glucose (GL) remained unchangeable during the two conditions. In summary, acute MEL ingestion after strenuous late-evening exercise attenuated transient leucocytosis and protected against lipid peroxidation and muscle damage induced by strenuous exercise the following morning in healthy male teenage athletes.  相似文献   
63.

MicroRNAs (miRNAs) play important roles in liver pathologies and they are potential biomarkers for diagnosis of liver diseases progression. Changes in miRNA sera expression can be used as non-invasive biomarkers for hepatocellular carcinoma (HCC). The aim of the study was to identify the miRNome profiling of HCC and its diagnostic value in distinguishing HCC from healthy individuals. Expression profiles of miRNAs in serum samples of 20 HCC patients and 10 healthy controls were detected. Whole miRNome profiling was done using next generation sequencing. Receiver operating characteristic (ROC) analysis was performed to assess the diagnostic performance of the deregulated miRNAs for discriminating HCC cases from healthy controls. MiRNA 142 was highly expressed in HCC (P value?=?0.023) while miRNAs 191, 22, and 126 were higher in the controls (P value?=?0.005, 0.034, 0.010 respectively). We have identified 5 novel miRNAs and they were highly expressed in HCC than controls. Analysis of ROC curve demonstrated that these deregulated miRNAs can be used as a reliable biomarker for detection of HCC with high diagnostic accuracy (AUC?=?0.93). We have detected a panel of serum miRNAs that can be used as a reliable noninvasive screening biomarker of HCC. The study recommends further research to shed light on a possible role of the newly discovered novel miRNAs in HCC pathogenesis.

  相似文献   
64.
Molecular Biology Reports - Arsenic is a potent and toxic heavy metal found in the environment that causes health problems, including liver disease, in humans and animals. Chlorogenic acid (CA) is...  相似文献   
65.
Pea is highly susceptible to pre-emergence damping off and foot rot after emergence caused by Mycosphaerella pinodes in western Algerian regions. Rhizosphere Actinomycetes which were antagonistic to the growth of this pathogen were isolated from chellif soils. An isolate of Streptomyces St7c5 provided superior seed protection. An increased in both germination and plant growth were recorded following treatment of seeds with Streptomyces formulated with inert or organic charge when compared to control. Application of the antagonist agent resulted in a significant reduction of Mycosphaerella foot rot to 5% compared with untreated seeds (25%). Hence, the talc formulation of Streptomyces agent can be recommended as one of the crop strategies for the management of foot rotting and blight caused by Mycosphaerella pinodes.  相似文献   
66.
The bacteria Bacillus thuringiensis mutant is highly producing melanin pigment with increased ultra violet resistance and insecticidal activity against the potato tuber moth Phthorimaea operculella (Zeller). The results showed that the high decrease of crystal protein formation rate ranged from 100% (B.t.EMS-M2 and B.t.EMS-M6) to 91.82% (B.t.EMS-M9). The EMS–UV-induced mutants (B.t.EMS–UV-2h-1, B.t. EMS–UV-2h-2, B.t.EMS–UV-2h-3, B.t.EMS–UV-2h-5, B.t.EMS–UV-4h-1, B.t.EMS–UV-4h-3 and B.t.EMS–UV-6h-2) showed 100% decrease in the crystal protein formation. Results also showed that the growth rate of B. thuringiensis isolates was detected by measuring the light absorption of culture broth (BP media at pH 8) at the wavelength of 600 nm. The absorbance values of the standard melanin were 2.055 and 0.134 at wavelengths of 226.5 and 602 nm, respectively. This means that the maximum absorbance at wavelength was 226.5 nm, this result is similar to that of the synthetic melanin which has the absorbance of 226 nm. Our experiments detected that the pigment extracted from the mutant isolate B.t.EMS-M3 (EMS-induced mutant) gave the maximum value of absorbance (2.615) at wavelength of 227.5 nm that was similar to standard melanin which gave absorbance value about 2.055 at a wavelength of 226.5 nm. This may be due to the genetic alterations that happened to the mutant isolates due to the mutation by EMS or/and UV irradiation.  相似文献   
67.
The combined effect of gamma radiation and both hot water and sodium carbonate on physiological decay and chemical constituents of stored mandarin fruits was investigated in this work. In this consideration, the studied fruits were gamma irradiated at doses of 0, 0.3, 0.6, 1.2 and 2.4 KGy. Then, the irradiated and non-irradiated fruits were treated either by hot water or sodium bicarbonate to examine their capacity to give a further maintenance and increasing shelf life or storage periods of mandarin. Treated and non-treated fruit samples were taken at intervals of 10 days and up to 60 days. Physiological decay, total acidity, vitamin C, total sugars and TSS were investigated during the different intervals. Gamma radiation treatments showed a promising effect for maintaining the studied fruits and retarding the development of decay. On the other hand, applying both hot water and sodium bicarbonate as a further combined treatments induced a powerful effect on delaying decay development, keeping the chemical constituents near to the normal level and in turn maximizing shelf life and storage periods of the fruits under investigation.  相似文献   
68.
The changes in lipid composition enable the micro-organisms to maintain membrane functions in the face of environmental fluctuations. The relationship between membrane fatty acid composition and UV-C stress was determined for mid-exponential phase and stationary phase Pseudomonas aeruginosa. The total lipids were obtained by dichloromethane/methanol (3:1) and were quantified by GC. The TLC analysis of phospholipids showed the presence of three major fractions phosphatidylethanolamine, phosphatidylglycerol, and cardiolipin. Significant modifications, as manifested by an increase of UFA, were obtained. Interestingly, this microorganism showed a remarkable capacity for recovery from the stressful effects of UV-C.  相似文献   
69.
Larger foraminifera of the Late Paleocene–Early Eocene lower slope to toe-of-slope deposits of the southern Galala, Egypt, are described. Sulcocassidina nakkadyi n. gen. et sp. (base) and Vacuolicassidella dakhlensis n. gen. et sp. (top) represent a phylogenetic line related to the family Cassidinidae (new family), superfamily Miscellanacea (new superfamily) in the latest Paleocene (shallow benthic zone 4) of the southern Galala, Egypt. In addition, Oscucassidella cassis n. gen. et sp., Pellatispiroides youssefi n. gen. et sp. and Chordcassidella ainshamsiana n. gen. et sp. are described and illustrated. Genus: Pomerolina n. gen. (Type species: Alveolina meandrina Carter, 1861, is newly erected and it belongs to Cassidinidae. In this family, the chambers are initially arranged streptospirally, whereas in later stages they are planispirally enrolled. Lateral chamberlets (retral process) are separated from the laminae by a passage and a marginal crest is added during growth.  相似文献   
70.
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