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The aim of this study was to determine the developmental changes of small leucine-rich proteoglycans (PGs), decorin, biglycan and fibromodulin, in ICR mouse retinas and to elucidate their role in the adult retina using kainic acid (KA)-induced retinal degeneration model. Retinas of prenatal, postnatal and adult mice were collected for histological and immunohistochemical staining to investigate the changes in distribution of these PGs. Decorin-and fibromodulin-immunostainings were diffusely distributed at prenatal and early postnatal stages and were stronger in the adult retina. However, biglycan was moderately distributed in the prenatal and early postnatal stages and was faint in the adult retina. Retinas were collected at 1, 3 and 7 days after intravitreal injection of KA. Retinas of KA injected eyes underwent shrinkage accompanied by serious damage in the inner layers. Decorin and fibromodulin were upregulated in the inner retinal layers of KA-injected eyes compared to the normal ones. Our results suggest that decorin and fibromodulin play key roles in retinal differentiation, and contribute to the retinal damage and repair process. However, biglycan may have no or only a limited role in the mouse retinal development or repair process.  相似文献   
3.
This paper explores the role of drainage as aninstrument for agricultural and rural development andthe related drainage development forces and processes.Five specific roles of drainage are distinguished:foodproduction, agricultural intensification anddiversification, sustainable irrigated land use, ruraldevelopment and environmental protection. Specialattention is given to the drainage development needsof the developing countries. It is argued that whileat early stages of agricultural development, drainagedevelopment is generally driven by ongoingagricultural development, at later stages ofdevelopment these roles often reverse withagricultural development risking to become stagnatedwhen drainage is not improved. These relationshipsshould be taken into account in the design of drainagedevelopment programs and projects. It is emphasizedthat improved drainage can contribute to establishinga more diversified, competitive and sustainable typeof agriculture, enhance sanitary and public healthconditions and generally contribute to ruraldevelopment, rural well being and poverty alleviation.Drainage development in the developing countries ishowever often severely constrained by the lack of supporting public policies, institutional frameworksand professional cadres. Overcoming these constraintsshould be given high priority on the national andinternational drainage development agendas.  相似文献   
4.
Foot and mouth disease (FMD) remains subclinical and self-limiting in small ruminants, but risk of spread of infection to susceptible cohorts is of great epidemiological significance; therefore, small ruminants must be included in vaccination campaigns in FMD endemic regions. Three groups of goats already immunized against peste des petits ruminants (PPR) were vaccinated with FMD and PPR vaccines alone or concurrently. The specific antibody response against three FMD virus strains and PPR virus were evaluated by competitive enzyme-linked immunosorbent assay (cELISA). Goats concurrently vaccinated with PPR + FMD vaccines had significantly (p < 0.05) higher antibody titers to two serotypes of FMD virus at 28, 45, and 60 days post-immunization compared to goats vaccinated with FMD vaccine alone, while goats vaccinated with PPR vaccines alone or PPR + FMD vaccines concurrently showed similar antibody kinetics against PPR virus up till 60 days post-vaccination. Overall, antibody kinetic curves for all three tested strains of FMD virus and PPR virus were similar in vaccinated groups during the course of experiment.  相似文献   
5.
Wesseling (1964) stated that standing water above drains as a result of submerged outlets creates a radial flow in the vicinity of the drains which promotes flow conditions so that a smaller rise of the water table height midway between drains results. Wesseling (1979) concluded the same for standing water above drains as the result of too high entrance resistance. Standing water above drains may also be due to overpressure in the drains as a result of too small pipe diameter or to irregular drain slopes. With the exception of submerged outlets the resulting water table rise midway between drains is however in the same order of the water table rise above the drain as can be derived from theoretical analysis. This conclusion was confirmed by measurements at an experimental field where the standing water above drains, as a result of overpressure, and the water table midway between drains were monitored in a field located at the northwest of the Nile Delta. In spite of the low discharge rates, overpressure was observed in the drains. It was mainly attributed to irregular drain slopes. The analysis of field data showed that the water table midway between drains rises at least the same as the water table height above the drains. Since overpressure in drains causes a decrease of the dewatering zone, a careful and accurate installation is of utmost importance for the proper functioning of a drainage system.  相似文献   
6.
Verification of drainage design criteria in the Nile Delta,Egypt   总被引:1,自引:0,他引:1  
A monitoring programme to verify the design criteria of subsurface drainage systems was conducted in a pilot area in the Nile Delta in Egypt. The programme, which covered a 9-year period, included the monitoring of the cropping pattern, crop yield, soil salinity, watertable, discharge and salinity of the drainage water and overpressure in the subsurface drainage system. The results showed that the yield of all crops (wheat, berseem, maize, rice and cotton) increased significantly after the installation of the subsurface drainage system. Optimum growing conditions for the combination of crops that are cultivated in rotation in the area required that the watertable midway between the drains had a average depth of 0.80 m. A corresponding drain discharge of 0.4 mm/d was sufficient to cope with the prevailing percolation losses of irrigation water and to maintain favourable soil-salinity levels. The additional natural drainage rate in the area was estimated at 0.5 mm/d. The most effective way to attain these favourable drainage conditions is to install drains at a depth between 1.20 to 1.40 m. For drain-pipe capacity the Manning equation can be used with a design rate of 1.2 mm/d, for collector drains this rate should be increased to 1.8 mm/d to compensate for the higher discharge rates from rice fields. These rates should be used in combination with a roughness coefficient (n) of 0.028 to take sedimentation and irregularities in the alignment into account. When this value of the roughness coefficient is used, no additional safety has to be incorporated in the other design factors (e.g. the design rate).  相似文献   
7.
About 30 years have passed since the Government of Egypt embarked on implementing a series of large scale drainage projects. At present, about 3.8 million acres have been provided with drainage systems on the basis of systematic pre-drainage investigations and designs. The target is to provide drains in approximately 6.4 million acres in the Nile Valley and Delta.The implementation of the subsurface drainage system is carried out by the public sector and private contractors under direct supervision of governmental regional departments. The implementation process depends on many factors related to the drainage material, machinery, manpower, site requirements, farmers and organizations involved. Problems and constraints are sometimes challenging, however, the annual rate of implementation has gradually increased to 170,000 acre/year.This paper discusses the different aspects involved in the implementation process of drainage systems. The development in materials, machinery and construction technologies will be reviewed. Institutional and management factors are going to be also considered.  相似文献   
8.
Sarcophine-diol (SD) is a semi-synthetic derivative of sarcophine with a significant chemopreventive effect against non-melanoma skin cancer both in vitro and in vivo. Recently, we have studied the effect of SD on melanoma development using the mouse melanoma B16F10 cell line. In this study, our findings show that SD suppresses cell multiplication and diminishes membrane permeability for ethidium bromide (EB), a model marker used to measure cell permeability for Ca2+ ions. SD also decreases protein levels of COX-2, and increases degradation of phospholipases PLA2 and PLCγ1 and diminishes enzymatic activity of the Ca2+-dependent cPLA2. This lower membrane permeability for Ca2+-ions, associated with SD, is most likely due to the diminished content of lysophosphosphatidylcholine (lysoPC) within cell membranes caused by the effect of SD on PLA2. The decrease in diacylglycerol (DAG) and inositol 1,4,5-triphosphate (IP3) due to inhibition of PLCγ1, leads to the downregulation of Ca2+-dependent processes within the cell and also inhibits the formation of tumors. These findings support our previous data suggesting that SD may have significant potential in the treatment of melanoma.  相似文献   
9.
Different classes of phytochemicals were previously isolated from the Red Sea algae Hypnea musciformis as sterols, ketosteroids, fatty acids, and terpenoids. Herein, we report the isolation of three fatty acids—docosanoic acid 4, hexadecenoic acid 5, and alpha hydroxy octadecanoic acid 6—as well as three ceramides—A (1), B (2), and C (3)—with 9-methyl-sphinga-4,8-dienes and phytosphingosine bases. Additionally, different phytochemicals were determined using the liquid chromatography coupled with electrospray ionization high-resolution mass spectrometry (LC-ESI-HRMS) technique. Ceramides A (1) and B (2) exhibited promising in vitro cytotoxic activity against the human breast adenocarcinoma (MCF-7) cell line when compared with doxorubicin as a positive control. Further in vivo study and biochemical estimation in a mouse model of Ehrlich ascites carcinoma (EAC) revealed that both ceramides A (1) and B (2) at doses of 1 and 2 mg/kg, respectively, significantly decreased the tumor size in mice inoculated with EAC cells. The higher dose (2 mg/kg) of ceramide B (2) particularly expressed the most pronounced decrease in serum levels of vascular endothelial growth factor -B (VEGF-B) and tumor necrosis factor-α (TNF-α) markers, as well as the expression levels of the growth factor midkine in tumor tissue relative to the EAC control group. The highest expression of apoptotic factors, p53, Bax, and caspase 3 was observed in the same group that received 2 mg/kg of ceramide B (2). Molecular docking simulations suggested that ceramides A (1) and B (2) could bind in the deep grove between the H2 helix and the Ser240-P250 loop of p53, preventing its interaction with MDM2 and leading to its accumulation. In conclusion, this study reports the cytotoxic, apoptotic, and antiangiogenic effects of ceramides isolated from the Red Sea algae Hypnea musciformis in an experimental model of EAC.  相似文献   
10.
The current experiment was carried out to evaluate the effect of different dietary chromium supplementation sources, chromium oxide (Cr2O3), chromium methionine (Cr‐Met), or chromium yeast (Cr‐yeast), at different levels each (500 or 1,000 ppb) on growth performance, physiological traits, and carcass characteristics of broiler chicks. A total of 490 seven‐day‐old Arbor Acres chicks were randomly distributed into 7 experimental groups each in 10 replicates of 7 birds each. The groups were control, 500 ppb Cr2O3, 1,000 ppb Cr2O3, 500 ppb Cr‐Met, 1,000 ppb Cr‐Met, 500 ppb Cr‐yeast, and 1,000 ppb Cr‐yeast. The results showed significant superiority of the organic chromium sources (Cr‐Met or Cr‐yeast) concerning body weight and weight gain, the group supplemented with 1,000 ppb Cr‐yeast consumed the lowest feed (3,185 g) and had the best feed conversion ratio (1.60) compared to the control (1.73). The chromium treatments recorded significantly better protein and lipid profile, antioxidant status, and immunological parameters than the control group. Similarly, dietary chromium supplementation increased carcass yield and decreased intestinal pathogenic bacteria. In conclusion, supplementing broiler diets with organic chromium sources at 1,000 ppb promotes growth performance, physiological traits, and carcass characteristics; such chromium treatments enhanced the antioxidant status and immunity levels of broilers.  相似文献   
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