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71.
The cDNA encoding a precursor of Liv-SGP-G, the most abundant crustacean hyperglycemic hormone-family peptide in the sinus gland of the whiteleg shrimp Litopenaeus vannamei, was cloned by RT-PCR coupled with 5′- and 3′-RACE. The determined cDNA sequence consisted of 621 nucleotides comprising a 69-bp 5′-untranslated region, a 357-bp open reading frame, and a 195-bp 3′-untranslated region. The deduced sequence of 72 amino acid residues corresponding to mature Liv-SGP-G was completely identical to that of natural Liv-SGP-G, determined in our previous study. The recombinant Liv-SGP-G was thereafter heterologously expressed in Escherichia coli, and its vitellogenesis-inhibiting activity in ex vivo cultured ovarian fragments was examined. The recombinant peptides inhibited vitellogenin gene expression with almost the same efficacy as that of natural Liv-SGP-G purified from sinus glands.  相似文献   
72.
Two feeding trials were carried out to determine the optimum feeding rates in juvenile olive flounder, Paralichthys olivaceus, at the optimum rearing temperature. Fish averaging 5.0 ± 0.11 g (mean ± SD) in experiment 1 and 20.2 ± 0.54 g (mean ± SD) in experiment 2 were fed a commercial diet at the feeding rates of 0%, 3.0%, 4.0%, 4.25%, 4.5% and 4.75% body weight (BW) day?1 and satiation (5.52% BW day?1) in experiment 1 and 0%, 1.0%, 2.0%, 3.0% and 3.5% BW day?1 and satiation (4.12% BW day?1) in experiment 2 at 20 ± 1 °C. Both feeding trials lasted for 2 weeks. Results from experiment 1 indicated that weight gain (WG) and specific growth rate (SGR) of fish fed to satiation were significantly higher than those of fish fed at other feeding rates while feed efficiency (FE) and protein efficiency ratio (PER) of fish fed at 4.25% BW day?1 were significantly higher than those of fish fed to satiation and fish fed at 3.0% BW day?1 (< 0.05). In experiment 2 WG, SGR and PER leveled out after the feeding rate of 3.5% BW day?1 whereas FE reached a plateau at 3.0% BW day?1. anova of FE indicated that the optimum feeding rates in 5.0 and 20 g juvenile olive flounder could be 4.25% and 3.0% BW day?1, respectively. Broken line analysis of WG suggested the optimum feeding rates of 5.17% and 3.47% BW day?1 in 5.0 and 20 g fish, respectively. Therefore, these results indicated that the optimum feeding rates could be >4.25 but <5.17% BW day?1 for 5.0 g, and it could be >3.0 but <3.47% BW day?1 for 20 g size of juvenile olive flounder at the optimum rearing temperature.  相似文献   
73.
In this study, normal and dichlorodicyanuric acid (DCCA)-treated wool slivers were ultrasonicated in formic acid aqueous solutions. The effect of the ultrasonication condition on the wool fiber splitting was examined and the mechanism of the splitting by ultrasonication in formic acid was elucidated. No wool fiber splitting occurred at formic acid content up to 70 %, but the fiber splitting accelerated as the formic acid content increased from 75 %. Although no fiber splitting occurred up to 450W ultrasonic power, the degree of splitting increased significantly with increasing ultrasonic power above 450W. The wool fiber splitting by ultrasonication was heterogeneous and FE-SEM observations revealed a three-step splitting process: 1) full removal of scale, 2) removal of cell membrane complex (CMC), and 3) fiber splitting. A comparison of the fiber splitting of normal and DCCA-treated wool revealed that the scale of the ultrasonication-treated wool was removed by peeling off rather than by dissolution.  相似文献   
74.
This study was conducted to investigate the effects of dietary propolis supplementation on growth performance, immune responses, disease resistance and body composition of juvenile eel, Anguilla japonica, in order to evaluate its bioavailability as a feed additive for this species. A total of 540 fish averaging 7.7?±?0.22?g (mean?±?SD) were randomly distributed into 18 tanks in groups of 30, and each tank was then randomly assigned to one of three replicates of six diets containing 0 (P0), 0.25 (P0.25), 0.5 (P0.5), 1.0 (P1), 2.0 (P2) and 4.0 (P4) % dietary propolis. At the end of 12?weeks of feeding trial, weight gain (WG), specific growth rate (SGR), feed efficiency (FE) and protein efficiency ratio (PER) of fish fed P0.5 diet were significantly higher than those of fish fed P0, P1, P2 and P4 diets (P?<?0.05). These parameters were 148.9%, 0.72% day?1, 94.4% and 2.9, respectively for fish fed P0.5 diet. Serum lysozyme activity of fish fed P0.5 (105.7 units mL?1) and P1 (106.0 units mL?1) diets were significantly higher than those of fish fed P0, P0.25, P2 and P4 diets. Mucus lysozyme activity of fish fed P1 (8.4 units 10?cm?2) diet was significantly higher than those of fish fed P0, P2 and P4 diets. Results indicated that the optimum dietary propolis supplementation levels could be 0.25?C0.5% for optimum growth and feed efficiency, and 0.5?C1% for enhanced immune responses and disease resistance in eel, A. japonica. This study may suggest that the dietary propolis level for the optimum immune responses could be higher than the level for the optimum growth of eel.  相似文献   
75.
BackgroundHepatocellular carcinoma is the most common primary hepatic malignancy in humans and dogs. Several differentially expressed molecules have been studied and reported in human hepatocellular carcinoma and non-neoplastic liver lesions. However, studies on the features of canine hepatocellular carcinoma are limited, especially related to the differential characteristics of neoplastic and non-neoplastic lesions.ObjectivesThe study''s objective was 1) to examine and evaluate the expression of arginase-1, P-glycoprotein, and cytokeratin 19 in canine liver tissues and 2) to investigate the differential features of hepatocellular carcinomas, liver tissue with non-neoplastic lesions, and paracancerous liver tissues in dogs.MethodsThe expression levels of three markers underwent immunohistochemical analysis in 40 non-neoplastic liver tissues, 32 hepatocellular carcinoma tissues, and 11 paracancerous liver tissues. Scoring of each marker was performed semi-quantitatively.ResultsArginase-1 and P-glycoprotein were significantly downregulated in hepatocellular carcinoma, compared with hepatic tissues with non-neoplastic diseases (p < 0.001). Expression levels of arginase-1 and P-glycoprotein were also significantly lower in hepatocellular carcinoma than in paracancerous liver tissues (arginase-1, p = 0.0195; P-glycoprotein, p = 0.047). Few cytokeratin 19-positive hepatocytes were detected and only in one hepatocellular carcinoma and one cirrhotic liver sample.ConclusionsThe results of this study suggest that downregulation of arginase-1 and P-glycoprotein is a feature of canine hepatocellular carcinoma; thus, those markers are potential candidates for use in differentiating hepatocellular carcinomas from non-neoplastic liver lesions in dogs.  相似文献   
76.
77.
We evaluated four fermented protein concentrates (FPCs) as a fish meal replacer in juvenile rainbow trout, Oncorhynchus mykiss. Ten diets were formulated to contain low‐temperature fish meal (LT‐FM), Vietnam fish meal (VT‐FM) and four types of FPCs as fish meal replacers (FPC‐A, B, C & D) at 30% and 50% FM replacement levels. FPC‐A was a mixture of solid‐state fermented soybean meal (SBM) and corn gluten meal (CGM) with Bacillus subtilis; FPC‐B was pretreated acid‐hydrolysed FPC‐A; FPC‐C and FPC‐D were FPC‐A + 2% shrimp soluble extract (SSE) and FPC‐B + 2% SSE, respectively. Triplicate groups of fish (average 15.4 g) were fed one of the experimental diets for 8 weeks. At the end of the feeding trial, fish fed the LT‐FM, FPC‐B, FPC‐C and FPC‐D diets showed significantly higher growth performance at 30% FM replacement than those of fish fed the FPC diets at 50% FM replacement. Fish fed 30FPC‐B, 30FPC‐C and 30FPC‐D diets showed higher weight gain (WG) than fish fed 30FPC‐A diet. Haematological parameters showed no clear trends among the experimental groups. Superoxide dismutase, lysozyme and myeloperoxidase activities were found to be higher in fish fed the LT‐FM, FPC‐A, FPC‐B, FPC‐C and FPC‐D diets at 30% FM replacement than in fish fed the FPC diets at 50% FM replacement. Antinutritional factors such as α‐ and β‐conglycinin, glycinin, trypsin inhibitors or zein were absent in FPC compared with SBM and CGM. Intestinal villi length and muscular thickness were significantly reduced in fish fed the VT‐FM and FPC diets at 50% FM replacement compared to fish fed the LT‐FM and FPC diets at 30% FM replacement. The results show that FPC‐B, FPC‐C, FPC‐D could replace up to 30% of LT‐FM in juvenile rainbow trout.  相似文献   
78.
This study aimed to identify potential biomarkers of canine pyometra and their correlations with clinical parameters. First, 90 dogs with pyometra and 26 healthy female dogs were compared. Then, paired samples (before and after ovariohysterectomy) from 22 dogs with pyometra and 9 healthy controls from the initial cohort were compared.Concentrations of acute inflammatory proteins, C-reactive protein (CRP) and serum amyloid A (SAA), and cell-free DNA (cfDNA), were significantly higher in dogs with pyometra than in clinically healthy dogs. Cell-free DNA was the most sensitive biomarker for systemic inflammation, based on the receiver operating characteristic curve analysis (area under the curve = 0.959). In addition, cfDNA and CRP were significantly associated with inflammation and organ injury-related clinical parameters.Following the surgical removal of the inflamed uterus, interleukin-6 (IL-6), high-mobility group box 1 (HMGB1), and procalcitonin (PCT) significantly decreased, whereas changes in CRP, SAA, and cfDNA were not significant. These findings indicate that cfDNA, CRP, and SAA are potential clinical biomarkers of systemic inflammation in dogs with pyometra and PCT, IL-6, and HMGB1 are potential biomarkers of clinical recovery.  相似文献   
79.
A thermoresponsive poly(VCa-co-fluorophore) hydrogel labeled with fluorescent dye was prepared using conventional radical polymerization. A poly(VCa-co-fluorophore) copolymer consisting of N-vinylcaprolactam (VCa) and 2D-π-A type pyran-based fluorescent dye (fluorophore) units behaves as a temperature-driven fluorescent thermometer. This polymer in aqueous solution underwent a phase transition at 27–45 °C. The morphology of the internal microstructure of the poly(VCa-co-fluorophore) hydrogel was observed using SEM.  相似文献   
80.
Colorimetric chemosensors are now considered as one of the most effective analytical method used in the environment monitoring. Colorimetric chemosensor for pH sensing can easily detect the primary danger or change of the surrounding environment pollution and source of infection and can prevent danger in the various fields. Quinaldine and Indole based colorants having the function of colorimetric chemosensors were synthesized. Each colorants are confirmed to compare the result of mass spectra with calculated mass of Quinaline and Indole respectively. UV-Vis spectroscopy revealed that the colors of each colorants solutions were changed in basic conditions while no changes were observed in acidic conditions.  相似文献   
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