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1.
Despite its importance in Mali’s economy, camel breeding in the country remains poorly documented, impeding effective policy-making in this regard. This study consisted in a 3-month survey and aimed at characterising camel breeding systems in Ansongo, in the region of Gao, Mali. It highlights the diversity of strategies adopted by breeders and their evolutions. Supplementary feeding and veterinary care were seldom practised. In zones close to the Niger River, cattle were substituted to camels. Transhumance routes also are modified but mobility keeps its vital role in the breeding system. Important differences within the study region in the classification of camel breeds have been reported that will influence the implementation of a collective action for animal genetic improvement. The improvement goals should take the actual management, including mobility and the mixed nature of the herds into account.  相似文献   
2.
Background: In this study, we evaluated the incidence of apoptosis at the ultrastructural levels and expression of some apoptosis-related genes in vitrified human ovarian tissue just after warming. Methods: Human ovarian tissue biopsies from 23 women after caesarean section were transported to the laboratory within 2 hours, and then they were cut into small pieces. Some pieces were vitrified and warmed and the other samples were considered as control. Apoptosis was assessed by a transmission electron microscope and also by molecular analysis of pro-apoptotic (Fas, FasL, Bax, p53, caspase8, and caspase3) and antiapoptotic (Bcl-2 and BIRC5) genem RNA levels using real-time RT-PCR before and after vitrification. Results: No sign of apoptosis was shown ultrastructurally in vitrified samples. The level of FasL, Bcl-2, Bax, p53, and caspase3 mRNA and Bax:Bcl-2 ratio were similar in non-vitrified and vitrified groups; however, the expression of Fas and caspase8 genes was higher and BIRC5 was lower in vitrified samples compared to non-vitrified group (P<0.05). Conclusion: The fine structure of human vitrified ovarian tissue was well preserved; moreover, vitrification was shown to affect the expression of some apoptosis-related genes. However, additional study is needed to confirm this observation.Key Words: Vitrification, Apoptosis, Gene expression, Ovary, Humans  相似文献   
3.
The aim of this study was to evaluate the effects of diets containing rice distillers’ by‐product (RDP) on growth performance, carcass characteristics, meat quality, and gut microbiota of fattening pigs. Twenty‐four crossbred finishing pigs (Duroc × Landrace × Yorkshire), 56.9 ± 3.1 kg initial body weight, were randomly allocated to three groups. For 56 days, pigs were fed one of three diets including RDP0 (control), RDP15 (15% RDP in DM), and RDP30 (30% RDP in DM). With RDP level in diet, average daily gain and backfat thickness linearly increased (p < 0.05), and drip loss tended to increase (p ≤ 0.08). In addition, 16S ribosomal RNA gene amplicon profiling showed that RDP was associated with modulation of colonic microbiota composition, especially at family and genus levels. Relative abundance of Porphyromonadaceae and Erysipelotrichaceae families in colonic digesta increased with inclusion of RDP, while that of Enterobacteriaceae decreased. The proportion of genera unclassified Erysipelotrichaceae, and Butyrivibrio increased as inclusion of RDP. These results indicate that up to 30% inclusion in diet of finishing pigs, RDP can modulate colonic microbiota composition, and induces an improvement of animal growth and fat deposition.  相似文献   
4.
Numerous studies have been conducted to examine the efficiency of PAM in controlling soil erosion under surface irrigation; however, there are fewer studies that have examined the effect of PAM on soil-water relations. This trickle irrigation laboratory study on a Jordanian clay loam soil addressed the effect of PAM on the spreading of the wetting front. PAM was added to the irrigation water under a trickle irrigation experiment where we irrigated the soil for 30 min. Four PAM concentrations (0.0, 5.0, 10.0, and 20.0 mg l?1) were used to examine its effect on the wetting front propagation in the soil. We also examined the effect of PAM on the soil water content, where we irrigated for 45 min, using two concentrations of PAM, 0.0 and 20.0 mg l?1. The soil water content was measured at depths of 0.0, 5.0, 10.0, 15.0, and 20.0 cm, 4 h, 24 h, and one week after completion of irrigation. PAM's effect on the soil water characteristic curve was studied using PAM concentrations of 0.0, 25, 50, and 100 mg l?1. In this study the spread of the wetting front on the soil surface and in the vertical and horizontal directions inside the soil profile increased when PAM was added to the irrigation water. As the PAM concentration increased the spreading of the wetting front increased. The average wetting front spreading increased in the vertical direction from 7.8 cm when PAM was not used to 8.3, 9.6, and 12.1 cm, for PAM concentrations of 5.0, 10.0, and 20.0 mg l?1, respectively. At the same time the average increase in the horizontal direction was from 18.4 to 18.5, 18.6, and 21.7 cm for PAM concentrations of 0.0, 5.0, 10.0, and 20.0 mg l?1, respectively. The second experiment showed that at a soil depth of 20 cm, volumetric soil water content (θv) was 15.2% when the irrigation water contained 20.0 mg l?1 of PAM compared to 13.9% when no PAM was added to the irrigation water. PAM did not have a significant effect on soil moisture characteristic curve.  相似文献   
5.
This study was conducted to determine actual evapotranspiration and crop coefficients at different growth stages of broad bean (Vicia faba L.) grown in an open field in the Jordan Valley, Jordan using a precise and accurate approach. The study involved 30-min fluxes measurements of energy budget components over broad bean crop using a complete setup of an Eddy Correlation (EC) system. The measurements were conducted during the three main crop growth stages namely initial, development, and midseason growth stages following the Food and Agriculture Organization of the United Nations (FAO) crop coefficient model for green harvested broad bean crop. The average crop coefficients during the initial (KC ini), development (KC dev) and midseason (KC mid) growth stages were 0.37, 0.8 and 1.05, respectively. The measured weighted average crop coefficient over the entire growing season KC GS was 9.5% lower than the FAO corresponding value.

Results showed that there was a clear decrease of (bulk) surface resistance (rs) as crop canopy developed. Daily average rs values were 855, 337, and 166?s/m for initial, development, and midseason growth stages, respectively. Moreover, rs was found to be highly correlated to crop height (hc). A simple linear relation between rs and hc with R2 of 0.91 was found. This relation will enable future direct determination of crop evapotranspiration (ETC) using Penman-Monteith equation without the need to calculate both grass reference evapotranspiration (ETO) and crop coefficient (KC) values.  相似文献   
6.

Background:

Ovarian tissue cryopreservation is an alternative strategy to preserve the fertility of women predicted to undergo premature ovarian failure. This study was designed to evaluate the expression of folliculogenesis-related genes, including factor in the germline alpha (FIGLA), growth differentiation factor-9 (GDF-9), follicle-stimulating hormone receptor (FSHR), and KIT LIGAND after vitrification/warming of human ovarian tissue.

Methods:

Human ovarian tissue samples were collected from five transsexual women. In the laboratory, the ovarian medullary part was removed by a surgical blade, and the cortical tissue was cut into small pieces. Some pieces were vitrified and warmed and the others were considered as non-vitrified group (control). Follicular normality was assessed with morphological observation by a light microscope, and the expression of FIGLA, KIT LIGAND, GDF-9,, and FSHR genes was examined using real-time RT-PCR in both the vitrified and non-vitrified groups.

Results:

Overall, 85% of the follicles preserved their normal morphologic feature after warming. The percentage of normal follicles and the expression of FIGLA, KIT LIGAND, GDF-9, and FSHR genes were similar in both vitrified and non-vitrified groups (P > 0.05).

Conclusion:

Vitrification/warming of human ovarian tissue had no remarkable effect on the expression of folliculogenesis-related genes. Key Words: Vitrification, Gene expression, Humans  相似文献   
7.
Surface irrigation is the oldest and the most widely used method of irrigation. One disadvantage of surface irrigation is soil erosion. New technology employing water-soluble polymers may provide a technique that is effective and affordable to control soil erosion. Water-soluble anionic organic compound known as polyacrylamide polymer (PAM) is the most successful polymer in controlling soil erosion. This study investigated the effect of spraying PAM on the soil surface to control soil erosion and to increase soil infiltration on a Jordanian clay loam soil. Different PAM concentrations, namely 5, 10, and 20 mg/l in addition to the control (0 mg/l) were used in this study. The highest effect of PAM on the measured properties was attained at 20 mg/l. We noticed that PAM's efficiency was decreased with subsequent irrigations. The reduction in soil erosion was 72 and 47.6%, the reduction in runoff water turbidity was 83 and 35%, the increase in water advance time was 6 and 0.9% and the increase in soil infiltration was 36 and 20.8% for the first and fourth irrigation, respectively. PAM's efficiency in flocculating soil particles was studied in the lab where we noticed that its efficiency in sedimentation was increased as its concentration increased.  相似文献   
8.
ABSTRACT

The objective of the current study was to determine the effects of chitosan (CH) coatings containing Mentha spicata essential oil (MSO; 0.2 and 0.4%) and zinc oxide nanoparticle (ZnO; 0.2 and 0.4%) on chemical (total volatile basic nitrogen (TVB-N), 2-thiobarbituric acid reactive substances (TBARS) and peroxide value (PV)), microbial (total viable count, psychrotrophic count, Pseudomonas spp., and Enterobacteriaceae) and sensory (odor, color, and overall acceptability) properties of raw rainbow trout fillets during 14 days of refrigerated storage. Final microbial population of CH + MSO 0.4% + ZnO 0.4% and CH + MSO 0.4% + ZnO 0.2% retarded approximately 3–5 log CFU/g as compared to control groups (P < 0.05). At the end of storage time in control samples, TVB-N, TBARS, and PV reached 49.3 mg N/100 g, 3.31 mg malonaldehyde/kg, and 2.04 meq peroxide/kg lipid, while the values for the treated samples with MSO (0.2 and 0.4%) in combination with ZnO (0.2 and 0.4%) remained lower than 25 mg N/100 g, 2 mg malonaldehyde/kg, and 1.1 meq peroxide/kg lipid, respectively. The results indicate a potential use of CH coating containing MSO and ZnO as an effective type of antimicrobial packaging to maintain quality of rainbow trout fillets.  相似文献   
9.
Many farmers in the Jordan Valley have switchedfrom traditional surface irrigationto pressurized irrigation systems. Inorder for these pressurized irrigationmethods to be effective, farmers must have adequate flow andpressure at each FarmTurnout Assembly (FTA). No on-demandirrigation concept has yet been implemented inthe Jordan Valley, and the rotation concept is still in use today. The JordanValley Authority (JVA) is the agency responsiblefor the distribution of water to farmers in the Valley. JVA engineers wereused to implement the irrigation rotationschedule, without any attention being paid to itseffect on the pressure in the network. Using MS Excel, a computer spreadsheet model was createdto examine the effect of selected rotation on thepressure in the network. This model was called theTurnout Pressure Simulation Program (TPSP).The TPSP model was used to map and identifyfarms that will incur pressure problems with any of the selected rotation schedules. This modelwas tested in the northern part of a pilotpressurized irrigation network known as TO2,and included 131 irrigated farm units (400 ha)located in Adassiyeh at the northern end of the Jordan Valley. The TPSP model was also usedto study illegal openings and the effect of these on the pressure in the network. The effect of four, eight, and 12 illegal openings was studied for a selectedrotation schedule, and an average reduction in pressure of 12%, 30%, and 44% was noted compared to when there were no illegal openings.  相似文献   
10.
This study aims to assess the suspended solids dynamics of the irrigation water, through total Suspended Solids (TSS) measures and field observations. Assessment is conducted along the distribution system in the Northern Jordan Valley. This study followed the water’s TSS conditions in the study area along its travel in King Abdullah Canal (KAC), in the pumping station (with all of its components) and in the delivery networks from the pumping station up to the farm units. TSS of the water in KAC fluctuates temporally and spatially. Pumping stations components performance with respect to TSS such as the bar rack, the static and the traveling screens, the settling basins and the well were evaluated. The design of settling basins showed acceptable specifications of the existing structure; however, management and operation conditions are the main concerns affecting their performance. This study showed the screens work with low efficiency because of operation faults and lack of maintenance especially for the traveling screen. Distribution network affects adversely the water’s TSS because of lack of flushing which enables sediments removal from the network, and prevents suspension process for the piled up sediments inside the network pipes. This study suggested using special points of low elevations in the network to flush piled up sediment out of the network. Finally, this study showed the flushing procedure the Jordan Valley Authority staff should take for cleaning the distribution network.  相似文献   
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