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1.
A 3 × 2 factorial experiment was designed to evaluate the effect of different ratios of fish meal (FM): sunflower meal (SFM) with or without exogenous xylanase supplementation on growth, feed utilization, digestive enzymes activities, apparent digestibility, intestinal and liver morphology and chemical composition of Nile tilapia, Oreochromis niloticus. Three isonitrogenous (329.80 g/kg of crude protein) and isoenergetic (18.46 MJ/kg gross energy) experimental diets were formulated as SFM1 (FM:SFM = 2:1), SFM2 (FM:SFM = 1:1) and SFM3 (FM:SFM = 1:2) based on protein content. Each diet was supplemented with 0 or 0.5 g/kg of exogenous xylanase and was fed to triplicate groups of twelve fish (with initial weight, 1.31 ± 0.02 g) for 84 days. After 84 days of feeding period, the highest weight gain, specific growth rate, protein efficiency, protein productive value and the best feed conversion ratio were recorded in fish fed either SFM1 or SFM2 supplemented with exogenous xylanase. Whereas lowest growth performance was recorded in fish fed SFM2 and SFM3 un‐supplemented with xylanase. The highest activities of chymotrypsin, trypsin, lipase, amylase, alkaline phosphatase and cholecystokinin were observed in fish fed SFM1 and SFM2 diets supplemented with xylanase. The highest ADCs of dry matter, protein, lipid and digestible energy were recorded in fish fed SFM1 and SFM2 diets supplemented with exogenous xylanase. Supplementation of exogenous xylanase improved muscularis mucosa thickness, height of mucosal folds and enterocytes of intestinal fish. Addition of exogenous xylanase increased the calcium and phosphorus retention. Results of this study indicated that the addition of exogenous xylanase to diet containing high inclusion level of sunflower meal improved growth, digestive enzymes, nutrient digestibility, histological morphometric of liver and intestine and nutrient retention.  相似文献   
2.
Although color Doppler ultrasonography has been used to evaluate testicular blood flow in many species, very little has been done in goat. Eight male Shiba goats were exposed to a single intramuscular injection of either gonadotropin-releasing hormone (GnRH group; 1 µg/kg BW) or human chorionic gonadotropin (hCG group; 25 IU/kg BW). Plasma testosterone (T), estradiol (E2) and inhibin (INH) were measured just before (0 hr) and at different intervals post injection by radioimmunoassay. Testis volume (TV) and Doppler indices, such as resistive index (RI) and pulsatility index (PI) of the supratesticular artery, were measured by B-mode and color Doppler ultrasonography, respectively. The results indicated an increase in testicular blood flow in both groups, as RI and PI decreased significantly (P<0.05), but this increase was significant higher and earlier in hCG group (1 hr) than in the GnRH group (2 hr). A high correlation was found for RI and PI with both T (RI, r= −0.862; PI, r= −0.707) and INH in the GnRH group (RI, r=0.661; PI, r=0.701). However, a significant (P<0.05) correlation was found between E2 and both RI (r= −0.610) and PI (r= −0.763) in hCG group. In addition, TV significantly increased and was highly correlated with RI in both groups (GnRH, r= −0.718; hCG, r= −0.779). In conclusion, hCG and GnRH may improve testicular blood flow and TV in Shiba goats.  相似文献   
3.
This study evaluated the impact of dietary ginger and liquorice supplementation on growth performance, physiological and histopathological profiles and heavy metal accumulation in Nile tilapia fingerlings. Fish (n = 1,800, 17.5 ± 0.11 g BW) were randomly distributed into four treatment groups in triplicates and received no supplementation (control group), 5 ml aqueous ginger extract/kg feed (ginger group), 4 ml aqueous liquorice extract/kg feed (liquorice group) or 2.5 ml ginger plus 2 ml liquorice aqueous extracts/kg feed (mix group). The ginger‐liquorice mix supply improved the growth performance and feed efficiency (p < .05), increased the haematocrit and haemoglobin (p < .05), leucocytes (p = .108), neutrophils (p = .054), serum total protein (p < .05), albumin (p = .011) and globulin (p = .094) but decreased (p < .05) the blood urea nitrogen and creatinine than feeding liquorice or ginger lonely compared to the control. Heavy metal loads in pond water induced lamellar telangiectasis of gills and necrosis with sloughing of intestinal villi tips. These detrimental effects were alleviated, and the intestinal villus length (p = .041) and crypt depth (p = .069) were increased with liquorice supply. In all treatment groups, heavy metal contents in fish flesh were lower compared to the control. Thus, using ginger and/or liquorice aqueous extracts can decrease heavy metal accumulation in the fish flesh and exert positive effects on growth performance, metabolic profile and the intestinal and gill morphology of Nile tilapia.  相似文献   
4.
Concentration of inositol phosphates, phospholipids, and RNA and its derivatives of ten Bangladesh soils varied between 17.5 and 150 ppm, 0.5 and 11.0 ppm, and 0.22 and 1.30 ppm respectively. Variation in inositol phosphates was related to total phosphate and organic phosphate contents. Variation in phospholipids was associated with total phosphate, organic phosphate, and organic matter contents whereas the variation in RNA and its derivatives was related to total phosphate contents of the soils. Maximum mineralization of inositol phosphates was obtained in the first 30 days either when incubated with lime or when submerged under water. A moderate rate was observed in the subsequent 30-day incubation periods. The mineralization was greater in soil which contained more organic matter and inositol phosphates. Mineralization also increased with pH. Liming enhanced mineralization as it induced conditions for the proliferation of phosphate transforming organisms.  相似文献   
5.
6.
Background

Canine mammary tumors (CMTs) are one of the most common malignancies in dogs and are associated with significant mortality. Serum tumor markers and non-coding microRNAs have gained widespread popularity in human oncology studies. The present study has two aims, first one is to investigate the miR-21 expression compared with changes in serum tumor markers (CEA and CA15-3) in CMT. The second aim is to detect the immunohistochemistry markers as vimentin, P63, and -SMA in CMT.

Methods

This study enrolled 17 female dogs: 10 with mammary tumors and seven controls without tumors. Blood samples were collected to measure miR-21, CEA, and CA 15-3, and histological samples were prepared for histological grading and immunohistochemistry.

Results

CA 15-3 was elevated in all animals, whereas CEA levels showed no change compared with controls. miR-21 was upregulated 12.84-fold in animals with CMT. The most frequently recorded CMT was the mixed type. Myoepithelial cells were identified by P63 immunoreactivity, but not SMA. High expression of miR-21 was observed with positive vimentin immunoreactivity, indicating the mesenchymal origin of the tumor cells.

Conclusion

The present study showed that miR-21 was elevated to a greater extent than CA 15-3 (12.84-fold vs. threefold). Tumors that was positive for vimentin immunoreactivity was also associated with an elevation in the levels of miR-21, showing that miR-21 is released from mesenchymal cells. These findings support the hypothesis that miR-21 may be a more sensitive, noninvasive indicator for CMT.

  相似文献   
7.
Recently, drought-induced damaging impact in reducing the crop growth and development is drastically ranked at the top under various abiotic stresses. And especially water stress at the reproductive growth stages termed as terminal drought has become a severe threat for mungbean productivity. To mitigate the drought stress condition, "bio-priming" has emerged as a newly agronomic and sustainable technique in improving the mungbean production. A 2-year field study during Kharif season 2017–2018 was conducted to investigate the efficacy of rhizobacteria seed priming in mungbean(AZRI mung-06), at Agronomic Research Area, Department of Agronomy, Bahauddin Zakariya University, Multan, Pakistan. The experiment comprised two factors containing F_A(seed treatments, control(dry seeds), hydro-priming, silicon(Si)-priming, and bio-priming(mixture strains of Pseudomonas fluorescens+Rhizobium phaseoli)) and F_B(irrigation water-regimes at various growth stages including leaf formation(L), stem elongation(S)+flowering(F)+pod formation(P) containing treatments are normal irrigation(I_(L+S+F+P)) and terminal drought stress(I_(F+P))). All the treatments were arranged in randomized complete block design under factorial design and were replicated thrice. Results indicated that the exposure of drought stress at flowering and pod formation stages hampered the morpho-physiological growth and yield of mungbean. Nevertheless, seed priming treatments particularly bio-priming were effective in alleviating the detrimental effects of drought stress. Bio-priming significantly increased the yield and yield components(seeds/plant, 1 000-grain weight and harvest index) of mungbean and regulated the activities/levels of antioxidants(superoxide dismutase, catalase, peroxidase, ascorbic acid, and total phenolics) under drought stress. Compared with the control, bio-priming increased the seed yield of mungbean by 8–12% under normal as well as drought stress conditions during both years of study. Bio-priming also improved the nutrient uptake behavior followed by Si-and hydro-priming treatments under terminal drought stress. The study emphasized the effectiveness of bio-priming as dual seed treatment method may be helpful for vigorous germination of mungbean production along with plant tolerance against terminal drought stress. Among the various treatments, plants treated with bio-priming technique compensated the grain yield due to having strong antioxidant defense system and better nutrient uptake behaviour under terminal drought stress. Economic analysis also concluded that bio-priming is the easiest, cost-effective, friendly, and sustainable approach for the maximization of the mungbean production.  相似文献   
8.
Soil organic carbon (SOC) and nitrogen (N) are two of the most important indicators for agricultural productivity. The primary objective of this study was to investigate the changes in SOC and N in the deep soil profile (up to 100 cm) and their relationships with crop productivity under the influence of long-term (since 1990) fertilization in the wheat-maize cropping system. Treatments included CK (control), NP (inorganic N and phosphorus (P) fertilizers), NPK (inorganic N, P and potassium fertilizers), NPKM (NPK plus manure), and M (manure). Crop yield and the properties of topsoil were measured yearly from 2001 to 2009. C and N contents were measured at five different depths in 2001 and 2009. The results showed that wheat and maize yields decreased between 2001 and 2009 under the inorganic fertilizer (NP and NPK) treatments. The average yield between 2001 and 2009 under the NP, NPK, NPKM, and M treatments (compared with the CK treatment) increased by 38, 115, 383, and 381%, respectively, for wheat and 348, 891, 2 738, and 1 845%, respectively, for maize. Different long-term fertilization treatments significantly changed coarse free particulate (cfPOC), fine free particulate (ffPOC), intramicroaggregate particulate (iPOC), and mineral-associated (mSOC) organic carbon fractions. In the experimental years of 2001 and 2009, soil fractions occurred in the following order for all treatments: mSOC>cfPOC>iPOC>ffPOC. All fractions were higher under the manure application treatments than under the inorganic fertilization treatments. Compared to the inorganic fertilization treatments, manure input enhanced the stocks of SOC and total N in the surface layer (0–20 cm) but decreased SOC and N in the deep soil layer (80–100 cm). This reveals the efficiency of manure in increasing yield productivity and decreasing risk of vertical loss of nutrients, especially N, compared to inorganic fertilization treatments. The findings provide opportunities for understanding deep soil C and N dynamics, which could help mitigate climate change impact on agricultural production and maintain soil health.  相似文献   
9.
Failure in the past to ascertain responsible fishing practices and equitable distribution of benefits under traditional leasing systems has motivated the Bangladesh government to work in partnership with non-governmental organizations (NGOs) and fishing communities in recent times. This paper discusses the operational approaches that were used to identify fishing people and create institutions for their increasing participation in local fisheries, and in making and enforcing resource use rules under various partnership arrangements. The group-based empowerment strategies of NGOs; their role in securing for the beneficiaries the access rights to water bodies; the provision of credits and inputs for employment and income generation activities showed some practical evidence of the concept of the poor as managers of the fisheries resources. The policy issues involved in the rights of local community members to catch fish for subsistence are also discussed, as well as the challenges associated with the difficulties of reconciling differing government (GO) and nongovernment (NGO) organization priorities and points of view with regard to target group identification and levels of responsibilities.  相似文献   
10.
Optimum time of combine harvesting for amenity grasses grown for seed   总被引:5,自引:0,他引:5  
The relationships between, and changes in moisture content, 1000-seed weight, germination percentage and seed yield were determined from anthesis onwards in ten amenity grasses in 1975. These relationships were used to indicate the optimum date for combine harvesting and to give some indication of the consequences which follow if harvest was not carried out at this stage. In all species seed moisture content declined, and 1000-seed weight and germination increased to a maximum value, during ripening.  相似文献   
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