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81.

Background:

Hyperlipidemia and oxidized-low-density lipoproteins (Ox-LDL) are important independent cardiovascular risk factors that have been shown to stimulate vascular smooth muscle cell (VSMC) proliferation. The purpose of the present study was to investigate the effect of vitamin E on Ox-LDL, lipid profile, C-reactive protein (CRP), and VSMC proliferation of rat aorta.

Methods:

Male Wistar rats (n = 32) were divided into four groups namely: sham (SH), control (C), non-treated diabetic, and vitamin E-treated diabetic (VETD) groups. Ox-LDL, lipid profile, CRP and VSMC proliferation of aorta were measured after 42 days.

Results:

The results revealed that along with a significant increase in VSMC proliferation, the amount of CRP, Ox-LDL, and lipid profiles in diabetic rats. VSMC proliferation was significantly ameliorated, and elevated CRP, Ox-LDL, and lipid profiles were also restored to those of shams in VETD.

Conclusions:

These findings strongly support the idea that diabetes induces Ox-LDL-mediated oxidative stress and VSMC proliferation in aorta of rat and imply that vitamin E has a strong protective effect as an antioxidant. Key Words: Ox-LDL, Vitamin E, Diabetes, VSMC proliferation  相似文献   
82.
Parental condition‐dependent offspring fitness is a well‐discussed issue in animal breeding research, while offspring environment and its interaction with parental condition are currently another very interesting topic to investigate the plasticity of phenotypic traits across an environmental gradient. The present study was, therefore, conducted following a half‐sib breeding design to test the effects of (a) paternal body size, (b) offspring feeding strategy (everyday and every other day) and (c) their interactions on fitness‐related traits (e.g., survival, total length and body area) of offspring of a commercially important aquaculture species, the Indian major carp (Labeo rohita). The analysis revealed that paternal body size had significant effects on offspring survival rate and total length, while no significant influence was found in body area. The study also showed that the offspring feeding strategy significantly affected all offspring traits. Interestingly, the study unveiled the significant interactive effects of paternal condition and offspring feeding for offspring survival rate and total length. These findings suggest that paternal size, offspring rearing environment and their interactions can influence offspring fitness‐related traits which are very essential information for the sustainable production of good quality larvae under variable dietary conditions.  相似文献   
83.
Since the 1950s, invertebrate fisheries catches have rapidly expanded globally to more than 10 million tonnes annually, with twice as many target species, and are now significant contributors to global seafood provision, export, trade and local livelihoods. Invertebrates play important and diverse functional roles in marine ecosystems, yet the ecosystem effects of their exploitation are poorly understood. Using 12 ecosystem models distributed worldwide, we analysed the trade‐offs of various invertebrate fisheries and their ecosystem effects as well as ecological indicators. Although less recognized for their contributions to marine food webs, our results show that the magnitude of trophic impacts of invertebrates on other species of commercial and conservation interest is comparable with those of forage fish. Generally, cephalopods showed the strongest ecosystem effects and were characterized by a strong top‐down predatory role. Lobster, and to a lesser extent, crabs, shrimp and prawns, also showed strong ecosystem effects, but at lower trophic levels. Benthic invertebrates, including epifauna and infauna, also showed considerable ecosystem effects, but with strong bottom‐up characteristics. In contrast, urchins, bivalves, and gastropods showed generally lower ecosystem effects in our simulations. Invertebrates also strongly contributed to benthic–pelagic coupling, with exploitation of benthic invertebrates impacting pelagic fishes and vice versa. Finally, on average, invertebrates produced maximum sustainable yield at lower levels of depletion (~45%) than forage fish (~65%), highlighting the need for management targets that avoid negative consequences for target species and marine ecosystems as a whole.  相似文献   
84.
The suitability of inland saline water (ISW) from the Lahli‐Baniyani Fish Farm, Rohtak was investigated for the larval rearing of giant freshwater prawn (GFP), Macrobrachium rosenbergii. Six experiments were conducted. In Experiment‐I, 54% of the larvae metamorphosed to postlarvae (PL) in constituted seawater (CSW) whereas total mortality occurred at larval stages (LS)‐II and LS‐III in ISW with salinity of 12 g L?1. Larvae survived to LS‐IV in Experiment‐II, when ISW was supplemented with K+~ SW. In Experiment‐III, total hardness in ISW was reduced serially, but K+ ~ SW was supplemented. The larvae did not survive beyond LS‐V. In Experiment‐IV, ISW was amended with different ratios of Mg2+/Ca2+ and K+ ~ SW. The larvae successfully metamorphosed to postlarvae with highest survival of 51.6% in Mg2+/Ca2+ ratio of 2.5. In Experiment‐V, eight larval cycles were run with water quality used in Experiment V, where all the cycles produced PL's with a survival rate of 20–67%. In Experiment VI, the larvae were reared in Mg2+/Ca2+ ratio of 2.5 and different levels of K+ to optimize its requirement. The ISW amended with K+ 80% ~ SW and Mg2+/Ca2+ ratio of 2.5 was found to be commercially suitable for the seed production of GFP.  相似文献   
85.
Chowdhury R  Hasan CM  Rashid MA 《Fitoterapia》2003,74(1-2):155-158
The extracts of two Bangladeshi medicinal plants, Toona ciliata (stem bark) and Amoora rohituka (stem bark), along with siderin, a major coumarin from T. ciliata, exhibited significant in vitro antibacterial activity. The extracts also demonstrated mild antifungal effect.  相似文献   
86.
In this study, we investigated N2O emissions from two fields under minimum tillage, cropped with maize (MT maize) and summer oats (MT oats), and a conventionally tilled field cropped with maize (CT maize). Nitrous oxide losses from the MT maize and MT oats fields (5.27 and 3.64 kg N2O-N ha−1, respectively) were significantly higher than those from the CT maize field (0.27 kg N2O-N ha−1) over a period of 1 year. The lower moisture content in CT maize (43% water-filled pore space [WFPS] compared to 60–65%) probably caused the difference in total N2O emissions. Denitrification was found to be the major source of N2O loss. Emission factors calculated from the MT field data were high (0.04) compared to the CT field (0.001). All data were simulated with the denitrification decomposition model (DNDC). For the CT field, N2O and N2O + N2 emissions were largely overestimated. For the MT fields, there was a better agreement with the total N2O and N2O + N2 emissions, although the N2O emissions from the MT maize field were underestimated. The simulated N2O emissions were particularly influenced by fertilization, but several other measured N2O emission peaks associated with other management practices at higher WFPS were not captured by the model. Several mismatches between simulated and measured \textNH4+ {\text{NH}}_4^ + , \textNO3- {\text{NO}}_3^ - and WFPS for all fields were observed. These mismatches together with the insensitivity of the DNDC model for increased N2O emissions at the management practices different from fertilizer application explain the limited similarity between the simulated and measured N2O emissions pattern from the MT fields.  相似文献   
87.
Basidiospores are implicated in the distribution and genetic diversity of Ganoderma boninense, cause of basal stem rot (BSR) and upper stem rot (USR) of oil palm (Elaeis guineensis). Measurement of aerial basidiospores within plantations in Sumatra showed continuous and high production over 24 h (range c. 2–11 000 spores m?3) with maximum release during early evening. Basidiospores applied to cut surfaces of fronds, peduncles and stems germinated in situ. Equivalent, extensive wounds are created during plantation harvesting and management and represent potential sites for formation of infective heterokaryons following mating of haploid basidiospore germlings. Use of spore‐sized micro‐beads showed that basidiospores could be pulled up to 10 cm into severed xylem vessels, where they are relatively protected from dehydration, UV irradiation and competing microflora. Diversity of isolates from five locations on two plantations was assessed by RAMS fingerprinting. Isolates from within individual palms with USR were identical and represent single infections, but different USR infections had unique band patterns and revealed separate infections. Some BSR‐affected trees contained more than one isolate, and thus had multiple infections. There was one example of adjacent BSR palms with the same isolate, indicating vegetative spread, but there were no identical genets from BSR infections and adjacent fallen palms. Isolate diversity was as great within a plantation as between plantations. It is evident that basidiospores play a major role in spread and genetic variability of G. boninense. Evidence for direct basidiospore infection via cut fronds, indirectly through roots via colonized debris and less frequently, infection by vegetative, clonal spread is considered.  相似文献   
88.
Factors affecting preferential flow and transport in the vadose zone need to be investigated by experiments and simulations to protect groundwater against surface applied chemicals. The objectives of this study were to investigate the effects of several factors (soil structure, initial soil water content (SWC), and application rate) and their interactions on the extent of preferential flow and transport in a sandy clay loam field soil using the time domain reflectometry (TDR) for measuring SWC and electrical conductivity (EC) in 12 treatments, modeling (by HYDRUS-1D and VS2DTI) the measured SWC and EC, and conducting statistical tests for comparing the means of the measured and modeled SWC and EC and solute transport parameters (pore water velocity and dispersion coefficient) obtained by inversely fitting in the CXTFIT program. The study results showed that the applied solution moved faster in the undisturbed, wet initial SWC, and higher application rate experimental conditions than in the disturbed, dry initial SWC, and lower application rate, respectively, based on the analysis of the changes in TDR measured SWC and EC with depth at 1, 2, 5, and 15?h of the experiments. However, the effects of interactive factors or treatments on water flow and solute transport were not clear enough. The modeling results showed that HYDRUS-1D was better than VS2DTI in the estimation of EC and especially SWC, but overall the models had relatively low performances in the simulations. Statistical test results also showed that the treatments had different flow and transport characteristics because they were divided into different groups in terms of the means of SWC and EC and solute transport parameters. These results suggest that similar experiments with more distinct interactions and modeling studies with different approaches need to be considered for better understanding the complex flow and transport processes in the vadose zone.  相似文献   
89.
90.
Animal bites are a major public health problem. The aim of this study was to conduct a survey of animal bites in Bursa, Turkey. Patients who sought medical care for animal bites over an 18-month period were included in our study (n = 1,715). Data were obtained from the registry of the Bursa State Hospital; 71.84% of the patients were men and 28.16% were women. Bites were most frequent among patients who were >18 years of age (comprising 60.83% of all bites). The anatomical site of the bite was recorded in all 1,715 cases, and 1,778 bite locations on the body were reported. The upper extremities were the most frequent sites of animal bites (53.83%), followed by the lower extremities (38.03%). Bites were most frequently inflicted by dogs (68.04%), followed by cats (28.45%), mice (2.56%), and other animals (hamsters, donkeys, horses, foxes, and rabbits together comprised 0.95% of the bites). As a result, bite incidents were mostly associated with males aged >18 years and occurred in the upper extremities. This study showed that dog bites constitute a major animal bite problem in Bursa, Turkey.  相似文献   
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