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1.
Macro- and microscopic characteristics of flank scales for 12 species were investigated from the Persian Gulf Coral Reefs. In Lutjanus argentimaculatus and L. russellii (family Lutjanidae), the scales of different flank regions were not different, while four characters showed variation in the scale of L. lutjanus i.e., scale shape (pentagonal, hexagonal and square), anterior margin (waved, scalloped and smooth), focus shape (circular and oblong) and focus position (postero-central and central), displayed variation. Scale type (ctenoid) and posterior margin (transforming ctenii) did not show variation and could be considered to be specific in this family. In Epinephelus chlorostigma (family Serranidae), the scales of flank regions did not display variation, while in E. areolatus, E. diacanthus and E. radiates, the scales showed considerable variation. The most variable characters were scale shape, posterior margin and focus shape. Therefore, in fish systematics studies on the base of scale, it is particularly important to compare scales from the same flank regions. Also, some criteria such as size-dependent alternation, ontogenetic changes and variation between flank regions, should be considered. This study supports the potential of scale morphology to help for the understanding of fish diversity in the coral reef ecosystem.  相似文献   
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The purpose of this study was to determine if the fluid mechanical stresses associated with turbulent blood flow can contribute to the sickling process. Blood from seven patients with sickle cell disease was subjected to intermediate and high levels of turbulent flow in vitro. Turbulence was quantitated by hot film anemometry. Control samples showed 20 +/- 3% sickled cells. Cells subjected to intermediate levels of turbulent flow showed 26 +/- 4% sickling (P less than 0.01); and blood subjected to high intensities of turbulence showed 31 +/- 4% sickling (P less than 0.01). A quantitative count by electronmicroscopy, performed in one patient, showed polymerization of the hemoglobin indicative of sickling in more cells subjected to turbulence than in the control sample. A turbulence-reducing agent, polyethylene oxide, diminished the augmentation of the sickling process as it reduced turbulence at comparable Reynolds numbers. These results support the hypothesis that a deleterious effect upon hemoglobin SS erythrocytes may occur due to the mechanical stresses of turbulent flow. The agitation associated with turbulent flow presumably modifies the stabilizing factors of the intracellular colloidal solution of hemoglobin, thereby contributing to sol-gel transformation. Such hydrodynamic stresses may supplement the previously described factors which contribute to sickle cell crises.  相似文献   
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Pithecellobium dulce has been used in traditional medicine to treat various ailments owing to its restorative properties. The biological activities and chemical profiles of the lipophilic fraction of P. dulce bark and leaves were assessed herein. Fatty acid methyl esters (FAME) and unsaponifiable matter (USM) were prepared and analyzed by GC/MS. A total of 40 compounds were identified in the bark saponifiable fraction, whereas 9 compounds were annotated in the leaves. Palmitic acid methyl ester was the major compound identified accounting for 41.48 % of the bark and 19.03 % of the leaves composition. Besides, linolenic acid methyl ester (22.40 %) and linoleic acid (12.69 %) were annotated in the leaves saponifiable fraction. A total of 63 compounds were detected in the bark USM and 4 compounds were identified in the leaves. Phytol represented the major component in the leaves (52.57 %) followed by lupeol (20.68 %) and lupenone (8.60 %). Meanwhile, n‐dodecane dominated in the bark USM accounting for 24.69 % of the total composition. The leaves and bark lipophilic fractions revealed moderate antioxidant and antibacterial activities. Both extracts showed no antifungal activity. No cytotoxicity was observed for both lipophilic fractions. P. dulce offers a good source of antioxidant compounds that can be introduced to food and pharmaceutical industry.  相似文献   
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Russian Journal of Bioorganic Chemistry - 3-(2-Thienyl)-5-aryl-1-thiocarbamoyl-2-pyrazolines were reacted with chloroacetone derivatives and hydrazonyl chloride derivatives in ethanol to afford the...  相似文献   
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Molecular Biology Reports - Chronic kidney disease (CKD) is condition characterized by a gradual loss of kidney function, patient with CKD suffering from a variety of immune system defects. This...  相似文献   
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Molecular Biology Reports - The leptin is discharged from breast adipose tissue and is overexpressed in breast cancer (BC). Conflicting relation of leptin with BC was reported. We investigated this...  相似文献   
9.
Color vision is most beneficial when the visual system is color constant and can correct the excitations of photoreceptors for differences in environmental irradiance. A phenomenon related to color constancy is color induction, where the color of an object shifts away from the color of its surroundings. These two phenomena depend on chromatic spatial integration, which was suggested to originate at the feedback synapse from horizontal cells (HC) to cones. However, the exact retinal site was never determined. Using the electroretinogram and compound action potential recordings, we estimated the spectral sensitivity of the photoresponse of cones, the output of cones, and the optic nerve in rainbow trout. Recordings were performed before and following pharmacological inhibition of HC-cone feedback, and were repeated under two colored backgrounds to estimate the efficiency of color induction. No color induction could be detected in the photoresponse of cones. However, the efficiency of color induction in the cone output and optic nerve was substantial, with the efficiency in the optic nerve being significantly higher than in the cone output. We found that the efficiency of color induction in the cone output and optic nerve decreased significantly with the inhibition of HC-cone feedback. Therefore, our findings suggest not only that color induction originates as a result of HC-cone feedback, but also that this effect of HC-cone feedback is further amplified at downstream retinal elements, possibly through feedback mechanisms at the inner plexiform layer. This study provides evidence for an important role of HC-cone feedback in mediating color induction, and therefore, likely also in mediating color constancy.  相似文献   
10.
Calf diarrhea is one of the major health challenges in cattle herds. The bacteriological examination of fecal samples collected from apparently healthy and diarrheic calves' revealed isolation of 26 E. coli isolates out of 56 calves with an incidence of 46.4%. Serogroups O1, O26, O44, O55, O115, O119, O125, O146, and O151 were identified from the collected fecal samples. Using PCR all isolates was positive for ompA gene species specific for E. coli. While stx1 and eaeA genes detected with incidence of 3.8 and 19.2% respectively from the isolates. The presence of stx2 gene was negative in the fecal isolates. Among colostrum samples 4 E. coli isolates were detected and serogrouped to O26, O55 and O119. They were negative for eaeA, stx1 and stx2 except strain number 4 (O55) was positive for stx1. E. coli strains were sensitive to norfloxacin (80.7%) and resistant to ampicillin and cefotaxime (100% each). Based on our findings, there was no association between occurrence of E. coli and age of calf (2–14 days), while bottle feeding calf colostrum may be a source of E. coli contamination.  相似文献   
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