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71.
Length weight relationships (LWR) of five marine fishes were estimated from the Bay of Bengal, Bangladesh. Fish samples were collected occasionally from fisher's catch with gill net (mesh size: 3 cm) during November 2019 to October 2020. Fishing was done overnight. Total length (0.1 cm) and body weight (0.01 g) of each individual were measured. We recorded maximum total length for P. maculatus (55.0 cm) and P. parmatus (39.0 cm).  相似文献   
72.
Molecular Biology Reports - Despite the advancements in primary brain tumour diagnoses and treatments, the mortality rate remains high, particularly in glioblastoma (GBM). Chemoresistance,...  相似文献   
73.
The antiviral protein kinase R (PKR) is an important host restriction factor, which poxviruses must overcome to productively infect host cells. To inhibit PKR, many poxviruses encode a pseudosubstrate mimic of the alpha subunit of eukaryotic translation initiation factor 2 (eIF2), designated K3 in vaccinia virus. Although the interaction between PKR and eIF2α is highly conserved, some K3 orthologs from host-restricted poxviruses were previously shown to inhibit PKR in a species-specific manner. To better define this host range function, we compared the sensitivity of PKR from 17 mammals to inhibition by K3 orthologs from closely related orthopoxviruses, a genus with a generally broader host range. The K3 orthologs showed species-specific inhibition of PKR and exhibited three distinct inhibition profiles. In some cases, PKR from closely related species showed dramatic differences in their sensitivity to K3 orthologs. Vaccinia virus expressing the camelpox virus K3 ortholog replicated more than three orders of magnitude better in human and sheep cells than a virus expressing vaccinia virus K3, but both viruses replicated comparably well in cow cells. Strikingly, in site-directed mutagenesis experiments between the variola virus and camelpox virus K3 orthologs, we found that different amino acid combinations were necessary to mediate improved or diminished inhibition of PKR derived from different host species. Because there is likely a limited number of possible variations in PKR that affect K3-interactions but still maintain PKR/eIF2α interactions, it is possible that by chance PKR from some potential new hosts may be susceptible to K3-mediated inhibition from a virus it has never previously encountered. We conclude that neither the sensitivity of host proteins to virus inhibition nor the effectiveness of viral immune antagonists can be inferred from their phylogenetic relatedness but must be experimentally determined.  相似文献   
74.
EcoHealth - Global amphibian populations are facing a novel threat, chytridiomycosis, caused by the fungus Batrachochytrium dendrobatidis (Bd), which is responsible for the severe decline of a...  相似文献   
75.

Understanding how microclimate and vegetation are associated during secondary succession is of primary importance for plant conservation in the face of the increasing land cover modification. However, these patterns are still unstudied for many plant communities. This study aimed to evaluate the structure (species richness, Shannon's diversity index, Simpson´s dominance index, abundance of each species, average height of species, species cover (%), species composition, and indicator values) of a low thorn forest fragment and to analyze its relation with microclimate along a successional gradient. Four stages of succession were delimited by the analysis of Landsat images, in the state of Tamaulipas, northeast Mexico. Statistical models incorporated species richness, diversity indices, abundance, height, and cover, as variables for searching differences between stages, or to evaluate microclimate associations. A total of 70 species, 54 genera, and 27 families were determined. Height of tree layer was the most important variable for discrimination of the successional stages. Conserved areas differed floristically from other stages, associated mainly with the lowest values of wind speed originated by tree layer characteristics. A significant association between species and microclimate was found, being wind speed and relative humidity the most important variables. Some species, due to their high importance values and their patterns of association with microclimate, may be considered as key taxa for low thorn forest, which is a threatened semitropical community in northeast Mexico. Conserved and late successional areas account for climatic regulation of this plant community, and the importance of these forest patches may be considered when establishing biodiversity protection areas.

  相似文献   
76.
The Protein Journal - As expected, several new variants of Severe Acute Respiratory Syndrome-CoronaVirus-2 (SARS-CoV-2) emerged and have been detected around the world throughout this Coronavirus...  相似文献   
77.
78.
Snakebite being medical emergency and known cause for increased mortality needs assessment and treatment on high-priority bases, even in patients of snakebite who appear fine initially. The current retrospective study presents the snake bites in Saudi Arabia from 2015 to 2018 reported by General Administration of Statistics and Information, Ministry of Health, Kingdom of Saudi Arabia. The data presented in the current study, was extracted, analyzed, and reported after getting ethical approval from institutional committee. Totally, 14,679 cases of snakebites were reported during the four-year study period, with a higher prevalence in males (80%) in their productive age. Most patients were within the age group between 25 and 44 followed by 44 to 64 years. The majority of snakebite affected inhabitants were reported from farms of the rural areas, commonly during night hours of spring and summer seasons when snakes are very active. Only 36 (0.24%) patients out of 14,679 were reported dead and 14,643 (99.63%) were discharged after the treatment. Awareness among the general public should be encouraged and early diagnosis and usage of proper snake antivenoms could be life-saving. The delay in appropriate treatment can lead to significant morbidity and mortality.  相似文献   
79.
This present research investigated variations in lipid profiles and important biomarkers of tissue damage in response to graded concentrations of alcohol administration in male Wistar rats. Group A (control) received distilled water while group B, C and D received 30%, 40% and 50% (v/v) alcohol respectively. Five rats each from groups A-D were sacrificed after day(s) 1, 7, 14, 21 and 28 of administration. A significant increase was observed at day 28 for serum cholesterol by 79% (group B), 78% (group C) and 47% (group D) together with serum phospholipid 58% (group B), 50% (group C) and 92% (group D). Serum triacylglycerol increased by 71% (group B), 43% (group C) and 16% (group D) at day 21, while concentration of serum albumin decreased at day 28 by 40.9% (group B), 50.2% (group C), 53.3% (group D) respectively when compared with control (group A). Serum aminotransferases and alkaline phosphatase specific activities, as well as creatinine and uric acid concentration increased in a concentration-dependent manner, following alcohol administration. Though most of these effects induced by alcohol were time- and concentration-dependent, 40% alcohol appear to be more stable, giving results consistent with alcohol-induced damages, with minimal mortality. This study therefore further validated dyslipidemia and imbalance in clinical biomarkers as hallmarks of tissue damage induced by excessive alcohol consumption with an insight on the time- and concentration-response relationship between alcohol consumption and its toxicity.  相似文献   
80.
ObjectiveTo analyze electromyographic (EMG) patterns and isokinetic muscle performance of shoulder abduction movement in individuals who sustained a cerebrovascular accident (CVA).DesignTwenty-two individuals who sustained a CVA and 22 healthy subjects volunteered for EMG activity and isokinetic shoulder abduction assessments. EMG onset time, root mean square (RMS) for upper trapezius and deltoid muscles, as well as the isokinetic variables of peak torque, total work, average power and acceleration time were compared between limbs and groups.ResultsThe paretic side showed a different onset activation pattern in shoulder abduction, along with a lower RMS for both muscles (21.8 ± 13.4% of the maximal voluntary isometric contraction (MVIC) for the deltoid and 25.9 ± 15.3% MVIC for the upper trapezius, about 50% lower than the control group). The non-paretic side showed a delay in both muscles activation and a lower RMS for the deltoid (32.2 ± 13.7% MVIC, about 25% lower than the control group). Both sides of the group of individuals who sustained a CVA presented a significantly lower isokinetic performance compared to the control group (paretic side ~60% lower; non-paretic side ~35% lower).ConclusionsShoulder abduction muscle performance is impaired in both paretic and non-paretic limbs of individuals who sustained a CVA.  相似文献   
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