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81.
This study was conducted to evaluate the roles of glycine betaine (GB) in mitigating deleterious effect of salt stress on lettuce. Lettuce plants were subjected to two salinity (0 and 100 mmol l?1 NaCl) and four GB levels (0, 5, 10, 25 mmol l?1). Salinity resulted in a remarkable decrease in growth parameters, relative leaf water content and stomatal conductance. Plants subjected to salt stress exhibited an increase in membrane permeability (MP), lipid peroxidation (MDA), leaf chlorophyll reading value, H2O2 and sugar content. Exogenous foliar applications of GB reduced MP, MDA and H2O2 content in salt-stressed lettuce plants. Salt stress increased Na and generally decreased other nutrient elements. GB reduced Na accumulation, but significantly increased other element contents under salinity conditions. The study showed that gibberellic acid (GA) and salicylic acid (SA) content in salt-stressed plants were lower than those of nonstressed plants. However, salinity conditions generally increased the abscisic acid content. GB treatments elevated the concentrations of GA, SA and indole acetic acid (IAA) at especially 10 and 25 mmol l?1 GB under salt stress conditions. It could be concluded that exogenous GB applications could ameliorate the harmful effects of salt stress in lettuce.  相似文献   
82.

Background

Rapid determination of blood electrolyte concentrations can help determine electrolyte status and delivery of effective volume of electrolyte solutions in field conditions.

Objective

To evaluate reliability of the i‐STAT, a point‐of‐care (POC) device, in measuring blood K+, Na+, and CI concentrations in cattle.

Animals

Ninety‐eight cattle with various diseases.

Methods

In this prospective study, blood samples collected from the jugular vein were processed for determination of K+, Na+, and CI concentrations in blood and plasma using the i‐STAT and auto‐analyzer (Cobas C501), respectively. Blood and plasma electrolyte data were subjected to student t‐test for comparison, the concordance analysis for agreement, accuracy, and precision, the Passing‐Bablok regression and the Bland‐Altman plot for reliability, and receiver operating characteristics curves for sensitivity (Se) and specificity (Sp).

Results

Plasma concentrations of K+ (4.39 versus 4.2 mmol/L; < .0001) and CI (100.30 versus 99.4 mmol/L; < .04) were greater than their concentrations in blood. Plasma and blood Na+ concentrations were similar (136.95 versus 136.8 mmol/L). The i‐STAT results were highly correlated with the Cobas C501 results (= 0.970, 0.922, and 0.866 for K+, Na+, and CI , respectively). Regression equations fitting blood (Y) and plasma (X) concentration did not deviate from the identity line for K+ (Y = −0.10 + 0.98 × X), Na+ (Y = X), and CI (Y = 3.04 + 0.96 × X). The mean bias (blood concentration ‐ plasma concentration) was −0.20 for K+ (= .03), −0.16 for Na+ (= .12), and −0.87 for CI (= .93). The i‐STAT had 76–100% Se and 87.7–100% Sp for assessing electrolyte statuses.

Conclusions and Clinical Importance

The i‐STAT yielded results that were in agreement with the auto‐analyzer, with negligible biases in measurement of plasma K+, Na+, and CI concentrations. The i‐STAT is a reliable POC device and can be used in field condition to assess electrolyte status in cattle.  相似文献   
83.
The antioxidant activity of the water extract of Tilia argentea Desf ex DC was determined by the thiocyanate method. The antioxidant activity of the water extract increased with the increasing amount of lyophilized extract (50-400 microg) added into the linoleic acid emulsion. Statistically significant effect was determined in 100 microg and higher amounts. Antioxidant activities of water extracts of tilia (Tilia argentea Desf ex DC), sage (Salvia triloba L.), and two Turkish black teas commercially called Rize tea and young shoot tea (Camellia sinensis) were compared. For comparison studies, 100 microg portions of extracts were added into test samples. All samples were able to show statistically significant antioxidant effect. Both of the tea extracts showed highest antioxidant activities, nevertheless, differences between tilia and sage and tilia and tea were not statistically significant (for both cases p > 0.05). Like antioxidant activity, the reducing power of water extract of Tilia argentea Desf ex DC was also concentration dependent. Even in the presence of 50 microg of extract, the reducing power was significantly higher than that of the control (p < 0.05) in which there was no extract. Unlike antioxidant activity, the highest reducing power activity was shown by sage extract. Among the tea extracts, young shoot extract was the most effective one, however, it had significantly lower activity than sage (p < 0.05). Although tea flower had the lowest reducing power activity, it was higher than that of tilia. But this difference was not statistically significant (p > 0.05). From these results, we could suggest that although the reducing power of a substance may be an indicator of its potential antioxidant activity, there may not always be a linear correlation between these two activities. In addition, antimicrobial activities of each of the above extracts were studied by disk diffusion methods on different test microorganisms. None of the extracts showed antibacterial activity on the studied microorganisms.  相似文献   
84.
The compositions of essential oils isolated from the aerial parts of Artemisia absinthium, Artemisia santonicum, and Artemisia spicigera by hydrodistillation were analyzed by GC-MS, and a total of 204 components were identified. The major components of these essential oils were camphor (34.9-1.4%), 1,8-cineole (9.5-1.5%), chamazulene (17.8-nd%), nuciferol propionate (5.1-nd%), nuciferol butanoate (8.2-nd%), caryophyllene oxide (4.3-1.7%), borneol (5.1-0.6%), alpha-terpineol (4.1-1.6%), spathulenol (3.7-1.3%), cubenol (4.2-0.1%), beta-eudesmol (7.2-0.6%), and terpinen-4-ol (3.5-1.2%). The antifungal activities of these essential oils were tested against 11 plant fungi and were compared with that of a commercial antifungal reagent, benomyl. The results showed that all of the oils have potent inhibitory effects at very broad spectrum against all of the tested fungi. Pure camphor and 1,8-cineole, which are the major components of the oils, were also tested for antifungal activity against the same fungal species. Unlike essential oils, these pure compounds were able to show antifungal activity against only some of the fungal species. In addition, the antioxidant and DPPH radical scavenging activities of the essential oils, camphor, and 1,8-cineole were determined in vitro. All of the studied essential oils showed antioxidant activity, but camphor and 1,8-cineole did not.  相似文献   
85.
Wheat production is a major source of income for most people and forms the backbone of the economy in Central Anatolia, Turkey. Sunn pest, known in Turkey since 1927, is one of the most harmful pests of wheat in this region where the infested area has reached 0.3 million ha and the cost of chemical application has reached US$ 2 million per year. Two species of Eurygaster, E. maura and E. austriaca, are prevalent in the region. Observations of tests carried out on different genotypes under natural field conditions and controlled greenhouse tests showed variable response of wheat to sunn pest. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
86.
ABSTRACT

This study describes the potential use of olive oil-lemon juice emulsions containing different levels of lemon juice (0, 25, 35, and 50% v/v) as a flavoring, preservative, and antioxidant agent in marinated anchovy. The phenolic content and antioxidant activity of lemon juice, olive oil, and olive oil-lemon juice sauces as well as chemical, oxidative, and sensorial changes of marinade samples were analyzed. Increasing the level of lemon juice in sauces retarded the chemical and oxidative changes of marinated anchovy. However, increasing the level of lemon juice more than 35% in sauces led to a decrease in sensorial acceptability. Chemical and oxidative qualities of all the sauced samples were in the limit of deterioration during 100 days of storage. Although marinated anchovy samples treated with sauce containing 50% lemon juice had a significant inhibitor effect on chemical and oxidative deterioration, samples treated with sauce containing 35% lemon juice received the highest overall acceptability score.  相似文献   
87.
The present study was performed to investigate streptococci of serological group B obtained from various sources and group B streptococcal reference strains for serotype, hyaluronate lyase enzyme activity, the occurrence of the hylB gene and the insertion sequence IS1548. All group B streptococci were identified by cultural, biochemical, and serological properties and by polymerase chain reaction amplification of species-specific parts of the 16S-23S rDNA intergenic spacer region, the 16S rRNA gene and the CAMP-factor (cfb) gene. Of the 73 group B streptococci investigated, 59 strains displayed hyaluronate lyase enzyme activity. All hyaluronate-lyase-positive strains and three phenotypically hyaluronate-lyase-negative strains had a hylB gene with an amplicon size of 3.3kb. Eleven of the 14 phenotypically hyaluronate-lyase-negative strains generated a hylB gene PCR product with a size of 4.6kb, and 10 of these strains displayed a IS1548 amplicon with a size of 0.98kb. The hyaluronate-lyase-negative isolates were mainly observed among group B streptococci of serotype III/Rib. All strains harbouring IS1548 had an additional copy of IS1548 located downstream of the C5a peptidase (scpB) gene.  相似文献   
88.
The effects of organophosphate insecticide methidathion (MD) on kidney tissue and the ameliorating effects of a combination of vitamins E and C against subchronic MD toxicity were evaluated in rats. Experimental groups were: control group (group I), 5 mg/kg body weight MD-treated group (group II), and 5 mg/kg body weight MD plus vitamin E plus vitamin C treated group (group III). The groups II and III were treated orally with MD on five days a week for four weeks. Vitamins E and C were injected at doses of 50 mg/kg body weight, i.m. and 20 mg/kg body weight, i.p., respectively, 30 min after the treatment of MD in the group III. Rats were anaesthesized and venous blood samples were collected by direct right ventricle heart puncture, in addition, the right kidney was removed for histopathological examinations and malondialdehyde (MDA) analyses after four weeks. The serum activity of cholinesterase (ChE) and the kidney level of malondialdehyde, and kidney histopathology were studied in rats. MD caused decreased ChE activity (group I: 2114 ± 63 U/L, group II: 1455 ± 100 U/L) and increased MDA level (group I: 147 ± 20.2 nmol/mg protein, group II: 236 ± 25.6 nmol/mg protein), and kidney damage in rats. Furthermore, a combination of vitamins E and C restored partially (ChE activity: 1670 ± 111 U/L, MDA level: 159 19.4 nmol/mg protein) this changes in MD-treated rats.  相似文献   
89.
SynCAM,a synaptic adhesion molecule that drives synapse assembly   总被引:1,自引:0,他引:1  
Synapses, the junctions between nerve cells through which they communicate, are formed by the coordinated assembly and tight attachment of pre- and postsynaptic specializations. We now show that SynCAM is a brain-specific, immunoglobulin domain-containing protein that binds to intracellular PDZ-domain proteins and functions as a homophilic cell adhesion molecule at the synapse. Expression of the isolated cytoplasmic tail of SynCAM in neurons inhibited synapse assembly. Conversely, expression of full-length SynCAM in nonneuronal cells induced synapse formation by cocultured hippocampal neurons with normal release properties. Glutamatergic synaptic transmission was reconstituted in these nonneuronal cells by coexpressing glutamate receptors with SynCAM, which suggests that a single type of adhesion molecule and glutamate receptor are sufficient for a functional postsynaptic response.  相似文献   
90.
Neospora caninum, a protozoan parasite, has been considered as one of the most important etiological agents responsible for abortion in dairy cattle throughout the world since it was first identified in dogs in 1988. In this report, characteristics of neosporosis, detected in a dairy cow ranch having epidemic abortions as high as 18.4%, were described. Blood samples were collected from 25 infertile or aborted dairy cattle, 6 calves born in 2006 and 40 heifers that were born in 2005 and raised in the same ranch. Necropsy was conducted in a 20-day-old Simmental calf that exhibited neurological signs including incoordination, head shaking, hyperextension in forelimbs and hindlimbs and tremor. The seroprevalance in aborted or infertile dairy cattle, heifers, and calves was 60%, 40%, and 33.3%, respectively. The mothers of seropositive two calves including clinically affected calf and its dam were N. caninum seropositive. In immunoperoxidase examinations, N. caninum antigen immunopositivity was observed in the degenerative and necrotic neurons in the brain, cerebellum as well as neurons in dorsal root ganglia of the cervical and thoracic regions of the spinal cord. In the heart, myocytes and Purkinje cells exhibited granular and linear patterns of immunoreactivity. Striated myofibers around the eyeball also showed immunolocalization for N. caninum antigen. Ultrastructurally, tachyzoites with typical apical complex, rhoptries and double-layered parasitic membrane were detected in the brain and heart sections. In conclusion, this report described clinical neosporosis for the first time in Turkey with tissue localization of the causative agents. This scientific communication also discusses the possible impact of cattle neosporosis by clinical, serologic and pathologic evidences collected from the survey of calves born in two successive generations in a ranch.  相似文献   
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