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21.
The primary goal of this project was to establish a protocol to freeze the sperm of the Caspian miniature horse in an attempt to start an intensive artificial insemination program to effectively increase the population of this breed, which has been listed as “Critical Rare Breed” by the American Livestock Breed Conservancy and is in danger of extinction. Commercially available equine freezing medium (EquiPRO CyoGuard Complete egg-yolk extender) was used for the initial setup of two different freeze protocols: slow and fast. The fast-freeze protocol had slightly better postthaw results and was used for a fertility demonstration. Five mares of proven fertility, aged 3 to 12 years, were used in the fertility trials, two of which resulted in pregnancy. This is the first report of pregnancy in the Caspian miniature horse using frozen semen, and the results seem to be a promising start to an extensive program to help this endangered breed, although further research on freezing protocols and conditions for this process are necessary to further improve the survival of semen and pregnancy rate.  相似文献   
22.
The present research aimed at evaluating the effects of sodium selenite and selenium nanoparticles (Se NPs) on iron homeostasis and the expression of transferrin and its receptor-binding protein genes. Twenty one Lori-Bakhtiary sheep were randomly allocated into 3 groups. Groups 1 and 2 orally received Se NPs and sodium selenite (1 mg kg(-1)) for 10 consecutive days, respectively. Group 3 served as the control. Blood and sternal bone marrow samples were collected at different supplementation intervals. Various factors such as serum iron concentration, total iron binding capacity (TIBC), and transferrin saturation percent were determined. The expression of transferrin and transferrin binding receptor genes was also studied. Results showed a decreasing trend in serum iron concentration particularly during the early and middle stages of supplementation (0-20 days) with Se NPs or selenium ions. Conversely, the TIBC level increased in sera especially during these periods (0-20 days) in animals that received selenium NPs or selenium ions. Our results also showed that expression of transferrin and its receptor genes was considerably increased during supplementation of the animals by both selenium compounds for 10 or 20 days. After this period, the expression of the mentioned genes significantly decreased, especially in animals that received selenium ions.  相似文献   
23.
In the current study we aimed to use PCR to investigate the presence of fetal DNA in the bovine (Bos taurus) cervical secretions and maternal serum, and to assess the effectiveness of this method in fetal gender determination. Pregnant uteri and pre-slaughter maternal blood samples were collected from 21 Holstein Frisian cows in a local abattoir. Overall, 13 male and 8 female fetuses were included in the study. Cervical mucus was sampled at the laboratory. After DNA extraction, the PCR amplified a 280?bp fragment from the X-chromosome and a 217?bp fragment from the Y-chromosome based on a sex-related polymorphism in the amelogenin locus. The presence of fetal Y-chromosome was confirmed in seven out of 13 cervical mucus samples collected from cows with male fetuses. Overall test sensitivity for correct sex determination based on PCR assay on cervical samples was equal to 71.4?±?2?%. In contrast, no fetal Y-chromosome DNA was detected in maternal serum samples from cows with male fetuses. This is the first report on validating the presence of fetal DNA material in the bovine cervical mucus and its potential usefulness for fetal sexing. Further investigations are needed to maximize the accuracy and evaluate the practicality of this approach.  相似文献   
24.

Objective

To examine the maturational competence, embryo development and expression of genes involved in oocyte maturation and cumulus expansion (GDF9, BMP15, HAS2, TNFAIP6, FGF17 and FSHr) following two standard methods of bovine COCs vitrification.

Methods

Bovine cumulus-oocyte complexes (COCs) were aspirated from slaughtered ovaries and then distributed into three groups: non-vitrified COCs (control), vitrification 1 group (V1); vitrification was performed by 15% ethylene glycol (EG) and 15% DMSO in holding media (TCM-199 with 20% FCS); and vitrification 2 group (V2); vitrification was performed by 40% EG in holding media. After vitrification, COCs were warmed in two steps and cultured and then evaluated for nuclear maturation, embryo development and gene expressions.

Results

The mean (±SD) percentages of nuclear maturation and blastocyst/cleaved were higher in control group (79.5 ± 8.0 and 31.0 ± 5.1%) than the V1 (34.8 ± 9.1 and 4.4 ± 5.1%) and V2 (47.8 ± 11.7 and 7.1 ± 5.8%) groups (P < 0.05), respectively. Further, COCs in V2 group showed higher mean (±SD) percentages of cleavage compared to V1 group (31.8 ± 1.0 vs 21.7 ± 2.8%; P < 0.05). GDF9 and BMP15 expression levels were higher in COCs in the control than of the vitrification groups (P < 0.05). In addition, expression level of GDF9 and BMP15 was higher in V2 group than in V1group (P < 0.05). The expression of HAS2 and FGF17 in V1 group was lower (P < 0.05) than that of the V2 groups.

Conclusions

Expression of oocyte maturation genes was affected by vitrification procedure and conditions. Using EG alone for vitrification of bovine immature COCs, resulted in higher expression of GDF9, BMP15 and production of more in vitro matured and cleaved oocytes.
  相似文献   
25.
The saturated hydraulic conductivity (\(K_{\text{s}}\)) is one of the important soil hydraulic properties which plays a significant role in developing flow transport models and irrigation and drainage practices. In this research, artificial neural networks approaches, group method of data handling (GMDH) model and a hybrid intelligent model based on combination of GMDH and harmony search (HS) model (GMDH-HS) were developed to estimate \(K_{\text{s}}\) based on 151 field samples collected from the northeast of Iran. Eleven topsoil properties were used as input parameters to estimate \(K_{\text{s}}\). The five quantitative standard statistical performance evaluation measures, i.e., coefficient of efficiency, root-mean-square error, mean square relative error, mean absolute percentage error and relative bias, were employed to evaluate the performance of various developed models. Statistical results indicated that the best performance can be obtained by GMDH-HS in terms of different evaluated criteria during the training and testing datasets for \(K_{\text{s}}\) estimation.  相似文献   
26.
This paper describes the effect of plant growth-promoting bacteria on sunflower growth and its phytoremediation efficiency under Cd-contaminated soils. Four levels of bacteria inoculation (non-inoculation, inoculation by Bacillus safensis, Kocuria rosea and co-inoculation by Bacillus safensis+Kocuria rosea) and four Cd concentrations (0, 50, 100 and 150 mg Cd per kg soil) were arranged as factorial experiment based on a completely randomized design (CRD). Results showed that Cd significantly decreased growth by decreasing the shoot and root length and biomass (p < 0.01). In addition, Cd dramatically decreases photosynthetic pigments, Fe transport to shoot and Zn uptake (p < 0.01). Bacterial inoculation increased Fe and Zn uptake by plants, Cd concentration in the aboveground part of plants and Cd uptake by the enhancement of Cd concentration in plant tissue and biomass production. Results showed that the highest shoot Cd uptake was ?observed in ?inoculated plants by Bacillus safensis at Cd100 (20.35 mg pot?1). However, in average of Cd treatments, the performance of co-inoculation in Cd uptake (13.04 mg pot?1) was better than singular inoculation (10.68 and 12.58 mg pot?1 for Bacillus safensis and Kocuria rosea, respectively). Results revealed that bacterial inoculation increased the Cd uptake performance in shoot and total biomass by 30% and 25%, respectively.  相似文献   
27.
Data set included records of 43303 cows for first lactation. Records were collected from 2000 to 2006 in Animal Breeding Center of Iran Studied traits were yield of milk, fat, protein and percentage of fat and protein. Total number of animal was 197561 individual in pedigree. Genetic and phenotypic parameters were estimated with REML method under single trait Animal Model. Breeding values were predicted with BLUP procedure. The model for the analyses included the factors herd-year-season as fixed factor (1694 levels), animal as random effect and age at calving as co variable with minimum and maximum of 23 and 36 month. Respectively the estimated heritabilities were 0.35 (+/-0.02), 0.33 (+/-0.02), 0.31 (+/-0.017), 0.28 (+/-0.02), 0.27 (+/-0.016) for milk, fat, protein yield, percent of fat and protein. Mean of breeding values of sires were 180.2 (+/-28.2), 3.7 (+/-1.26), 2.3 (+/-1.06), -0.036 (+/-0.014) and -0.028 (+/-0.009) for milk, fat, protein yield, percent of fat and protein, respectively.  相似文献   
28.
Understanding the volatile profile of melon is an ever increasingly important task for breeders for enhancing their flavour component. For this purpose, F1 progeny and parental lines were analysed using headspace-solid phase microextraction gas chromatography–mass spectrometry-based analysis. Diallel analysis showed that most of the investigated compounds were controlled via non-additive genetic effects with general combining ability to specific combining ability ratios of less than 0.4. High heterosis results were observed in alcohols such as ethanol and octanol in both rind and mesocarp samples and benzylalcohol in the rind. It was also noted that the ester-based compounds with high heterosis values in mesocarp samples differed from those with heterosis in rind samples. These observations further emphasize the non-additive control of these compounds. It can be concluded that non-additive genetic control is strongly governing the genetic profile within the studied progeny. This finding indicated that dudaim lines as a valuable genetic material enhanced the volatile profile of odourless commercial types of ameri and inodorus melon.  相似文献   
29.
This study was carried out to assess the effects of Pediococcus acidilactici on zebrafish (Danio rerio). Different levels of P. acidilactici including 0, 1 × 106, 2 × 106, 4 × 106 and 8 × 106 colony‐forming unit per g of the diet (cfug?1) were examined in fish with 120 ± 10 mg weight for 60 days in a completely randomized design. The results showed that the best growth indices were recorded in group 4 × 106 cfug?1 (p < 0.05). The highest number of total viable count and lactic acid bacteria of intestine were found in group 4 × 106 cfug?1 (p < 0.05). The maximum activity of digestive enzymes including amylase, lipase, protease and alkaline phosphatase was observed in group 4 × 106 cfug?1. The highest activity for superoxide dismutase was recorded in group 4 × 106 cfug?1 while catalase, glutathione peroxidase and glutathione reductase showed the highest activity in group 8 × 106 cfug?1. The most growth inhibition zone of Aeromonas hydrophylla, Flavobacterium columnare, Vibrio anguillarum and Edwardsiella tarda was found in group 4 × 106 cfug‐1 (p < 0.05). Therefore, P. acidilactici as a probiotic improved growth and immunity of the zebrafish and could be used by zebrafish farmers.  相似文献   
30.
Beta-cryptoxanthin (b-Cr) is a pro-vitamin A and one of the major carotenoids that can be commonly found in mammalian serum and tissues. Foods rich in certain fatty acids are known to be effective to gain a healthy immune system. In the present study, we evaluated the effect of b-Cr on rabbit humoral and cellular immune responses to have a better vision about the mechanism of effect of carotenoids on immune system. Twenty rabbits were randomly divided into five groups (4 per group): Groups consisted of: 1) control group (normal saline; 2) b-Cr (control); 3) vaccine control; 4) 5 mg/kg b-Cr o.p. + vaccine; 5) 10 mg/kg b-Cr o.p. + vaccine. Blood samples were obtained from the marginal ear artery at three time points: days 0, 14 and 21 of the study. Blood CD4+ and CD8+ lymphocytes and Serum Immunoglobulin and Cytokines content were evaluated. Results show that b-Cr administration increased the blood CD4+ lymphocytes count (P?>?0.01). Serum IgG, IgM and IgA levels increased (P?>?0.05) following b-Cr administration. b-Cr treatment increased serum IL-4 levels (P?>?0.05). According to presented results, b-Cr may increase the humoral immunity in mammals. So, it would possible has a potentially beneficial effect on health and on prevention of the immunity related diseases.  相似文献   
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