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101.
This study aimed to assess preslaughter factors responsible for the occurrence of bruises to front, rib, loin, hip, and round sites of cattle carcasses. Data from the slaughter of 148 loads of cattle were assessed, totaling 4,611 carcasses. Evaluated bruising factor variables were animal gender, journey distance (km), vehicle type (m²), journey time (hours), load density (kg/m2), handling and facilities conditions (optimal, acceptable, and unacceptable), and unloading waiting time (min). Gender had the strongest influence on carcass bruising, being the first variable to enter in the majority of models related to the carcass sites. Female carcasses displayed higher bruising in all sites. Densities above 401 kg/m² caused more bruising. With the exception of the loin, unacceptable, and acceptable conditions assigned to farm facilities and handling resulted in higher average bruising. Articulated vehicles with a greater load capacity were more likely to cause bruising. The effects of variables causing bruises act differently in the various carcass sites. In this sense, the results of this study suggested possible management practices for specific problems during the preslaughter period to minimize losses by bruising to different carcass sites.  相似文献   
102.
The objective of this study was to evaluate different concentrations of growth hormone (GH) on the development of bovine preantral follicles cultured included in the ovarian tissue (in situ) on the rates of morphologically normal, viable, primordial and developing follicles, as well as the oocyte and follicle diameter and ultrastructural analysis. Ovarian fragments collected from cows with no cross‐breeds defined were cultured in situ for 1 and 7 days in minimal essential medium (α‐MEM+) supplemented with different concentrations of recombinant human GH (0, 10, 25, 50 ng/ml). The ovarian fragments non‐cultured (control) and cultured were processed for classic histology, mechanical isolation and electron transmission microscopy (MET). The parameters underwent anova (Tukey′s and Dunnett′s tests) and chi‐square test (χ2). After 7 days of culture, the treatment with 50 ng/ml GH showed no differences with fresh control (p > 0.05) and had greater effectiveness than in the 0, 10 and 25 ng/ml GH concentrations of the morphologically normal follicles. Regarding the primordial follicles, a reduction was observed in the 50 ng/ml GH concentration concomitant with the significant increase in developing follicles, differing from both the fresh control and the other GH concentrations tested. In addition, 50 ng/ml GH showed a larger follicle and oocyte diameter when compared to the other treatments cultured. Similar structures were ultrastructurally observed in the control group, 50 ng/ml GH. Follicles cultured in 10 ng/ml GH showed nuclear invagination, vacuoles and lesioned basal membrane. Hence, it is concluded that 50 ng/ml GH is the most effective concentration for the development of preantral follicles cultured in situ.  相似文献   
103.
BACKGROUND: The spider mite, Tetranychus urticae, is the major strawberry pest in Brazil. The main strategies for its control comprise synthetic acaricides and predatory mites. The recent register of a commercial formula of azadirachtin (Azamax® 12 g L?1) can be viable for control of T. urticae. In this work, the effects of azadirachtin on T. urticae and its compatibility with predatory mites Neoseiulus californicus and Phytoseiulus macropilis in the strawberry crop were evaluated. RESULTS: Azadirachtin was efficient against T. urticae, with a mortality rate similar to that of abamectin. In addition, the azadirachtin showed lower biological persistence (7 days) than abamectin (21 days). Azadirachtin did not cause significant mortality of adult predatory mites (N. californicus and P. macropilis), but it did reduce fecundity by 50%. However, egg viability of the azadirachtin treatments was similar to that of the control (>80% viability). The use of azadirachtin and predatory mites is a valuable tool for controlling T. urticae in strawberry crop. CONCLUSIONS: Azadirachtin provided effective control of T. urticae and is compatible with the predatory mites N. californicus and P. macropilis. It is an excellent tool to be incorporated into integrated pest management for strawberry crop in Brazil. Copyright © 2012 Society of Chemical Industry  相似文献   
104.
The purpose of this study was to evaluate oxidative stress, antioxidant biomarkers, and performance during a multiday 210-km endurance race. Nine endurance athlete horses participated in this study. Samples were always taken at the same times of day, before the beginning of the race and after every day of competition. Analytic measurements included glutathione reductase (GR) and catalase activity, thiobarbituric acid–reactive substances (TBARs), and reactive carbonylated derivatives. Competition intensity was low, with an average speed of 12.56 ± 0.9 km/h. Four horses were unable to finish the race because of metabolic problems or fatigue. GR activity increased progressively (P < .001) throughout the competition, and TBARs showed a significant rise compared with baseline values (P < .01) but remained at the same levels throughout the 3 days of competition. Catalase and reactive carbonylated derivatives did not show any significant alterations in any time period. The best performance was obtained from horses who demonstrated higher GR capacity and/or lower TBAR concentration. In conclusion, redox status seems to modulate horses' performance in endurance races, but further studies are needed to better determine the adequate oxidant/antioxidant ratio to acquire optimal performance.  相似文献   
105.
The objective of this study was to evaluate the effects of spray‐dried porcine plasma (SDPP) on performance, measurement of thyroid hormones triiodothyronine (T3) and thyroxine (T4), body temperature and relative organ weights of weaned piglets exposed to a heat stress or a thermoneutral environment. One hundred and forty‐four piglets with initial BW of 5.82 ± 0.33 kg (28 d old) were used. The experimental design was a 4 x 2 factorial arrangement, four plasma levels (0.0, 2.5, 5.0 and 7.5%) and two environments (34º [heat stress (HS)] and 24°C [thermoneutral (TN)]). SDPP was fed from weaning (28 d of age) to the end of the trial (piglets were weighed at the beginning, 7, 21 and 35 days of trial). Rectal, neck, shoulder and leg temperatures were measured every seven days. At 21 days of trial, one piglet per pen was slaughtered to determine the weight of the carcass and organs. Blood samples were collected at 18 and 35 days of trial to determine levels T3 and T4. The rectal, neck, shoulder and leg temperatures were increased (p < 0.05) 0.4, 1.5, 1.0 and 1.3ºC, respectively, and relative weight of the lungs (p < 0.05) and total T3 (p < 0.05) were decreased 0.001 kg/kg and 0.19 ng/dl, respectively, for pigs in the HS environment. The estimated inclusion of 5.1% of SDPP had the greatest (p < 0.05) weight gain during the first week, and throughout the nursery phase, the 5% of inclusion had a tendency of improvement (p = 0.075), regardless of ambient temperature. For the entire period, pigs reared in the HS environment had the greatest (p < 0.05) estimated feed intake by the quadratic regression with the inclusion of 4.3% of SDPP.  相似文献   
106.
Cows experiencing high levels of inflammation and specific metabolic conditions tend to have slower follicular growth and lower serum and follicular concentrations of oestradiol (E2). Paraoxonase1 (PON1) activity decreases during inflammatory processes. Therefore, the aim of this study was to evaluate the association between serum and intrafollicular (FF) PON1 activity and the serum and intrafollicular levels of E2 and progesterone (P4), as well as the mRNA expression of genes related to steroidogenesis, metabolism and inflammation in the first post‐partum dominant follicle of Holstein cows. No correlation was found between PON1 activity, the expression of the analysed genes and levels of follicular E2 and P4, except for a negative correlation between serum E2 and follicular PO1 activity. Also, no correlation was found between serum and follicular PON1 during the first post‐partum follicular wave.  相似文献   
107.
The activities of antioxidant enzymes and photosynthetic responses were investigated in tomato (Lycopersicon esculentum L. var.) pre-treated by plant activators and inoculated by Xanthomonas vesicatoria. Plants were sprayed with acibenzolar-S-methyl, ASM [Bion® 50 WG (0.2 g l−1)] and aqueous extract from dry necrotic tissue flour (VLA) of ‘Lobeira’ (Solanum lycocarpum) bush. Four days later, the plants were challenged with a virulent strain of X. vesicatoria, under greenhouse conditions. Tomato leaves were then assessed to determine the activities of the main antioxidant enzymes: superoxide dismutase (SOD), catalase (CAT), peroxidase (POX), and ascorbate peroxidase (APX). A reduction of bacterial leaf spot severity was observed in plants treated by ASM (49.3%) and VLA (31.4%), without any in vitro inhibitory activity over the pathogen. Controls showed decreases in CO2 assimilation, transpiration, photosynthetic rates, and stomatal conductance. Water use efficiency and carboxylation efficiency were strongly affected in ASM- and VLA-treated, in comparison to controls and healthy plants. The tested substances induced increases in SOD and CAT activities in a delayed enzymatic response typical in compatible plant–pathogen interactions. Measured at daily intervals, activities of APX and POX were significantly (ρ0.05) higher in treated plants than in controls, except for APX in ASM-treated plants where no difference was found when compared to controls. Only POX was clearly induced at the earlier stages after spraying the tomato plants with ASM or VLA. Our results suggest that late increases in antioxidant enzyme activities may play a role in mitigating oxidative damage in restoring the photosynthetic imbalance imposed by the expansion of bacterial lesions.  相似文献   
108.
Assessment of pesticide residues in honey samples from portugal and Spain   总被引:1,自引:0,他引:1  
Fifty samples of honey collected from local markets of Portugal and Spain during year 2002 were analyzed for 42 organochlorine, carbamate, and organophosphorus pesticide residues. An analytical procedure based on solid-phase extraction with octadecyl sorbent followed by gas chromatography-mass spectrometry (GC-MS), for organochlorines, and by liquid chromatography-atmospheric pressure chemical ionization-mass spectrometry (LC-APCI-MS), for organophosphorus and carbamates, has been developed. Recoveries of spiked samples ranged from 73 to 98%, except for dimethoate (40%), with relative standard deviations from 3 to16% in terms of repeatability, and from 6 to 19% in terms of reproducibility. Limits of quantification were from 0.003 to 0.1 mg kg(-)(1). Most of the pesticides found in honey were organochlorines. Among them, gamma-HCH was the most frequently detected in 50% of the samples, followed by HCB in 32% of the samples and the other isomers of HCH (alpha-HCH and beta-HCH) in 28 and 26% of the samples, respectively. Residues of DDT and their metabolites were detected in 20% of the samples. Of the studied carbamates, both methiocarb and carbofuran were detected in 10% of the samples, pirimicarb in 4% and carbaryl in 2%. The only organophosphorus pesticides found were heptenophos in 16%, methidathion in 4%, and parathion methyl in 2% of honey samples. Results indicate that Portuguese honeys were more contaminated than Spanish ones. However, honey consumers of both countries should not be concerned about the amounts of pesticide residues found in honeys available on the market.  相似文献   
109.
The adjuvant activity of Chenopodium quinoa (quinoa) saponins on the humoral and cellular immune responses of mice subcutaneously immunized with ovalbumin (OVA) was evaluated. Two quinoa saponin fractions were obtained, FQ70 and FQ90, and 10 saponins were determined by UPLC/Q-TOF-MS. Mice were immunized subcutaneously with OVA alone or adjuvanted with Quil A (adjuvant control), FQ70, or FQ90. FQ70 and FQ90 significantly enhanced the amount of anti-OVA-specific antibodies in serum (IgG, IgG1, and IgG2b) in immunized mice. The adjuvant effect of FQ70 was significantly greater than that of FQ90. However, delayed type hypersensitivity responses were higher in mice immunized with OVA adjuvanted with FQ90 than mice treated with FQ70. Concanavalin A (Con A)-, lipopolysaccharide-, and OVA-stimulated splenocyte proliferation were measured, and FQ90 significantly enhanced the Con A-induced splenocyte proliferation. The results suggested that the two quinoa saponin fractions enhanced significantly the production of humoral and cellular immune responses to OVA in mice.  相似文献   
110.
In this study, the role of Cyperus sp. was evaluated for removal of pollutants from swine wastewater. Vertical-flow pilot scale constructed wetlands (CWs) operating with a hydraulic retention time (HRT) of 72 h were monitored in a greenhouse, located in Viçosa, Brazil. Significant differences were observed for the following parameters: Kjeldahl nitrogen, total phosphorus, alkalinity and electric conductivity, with averages removals of 37.5 and 28.5%, 55.9 and 44.4%, 30.2 and 25.6 and 26.1% and 22.9% (for planted and unplanted CWs, respectively). The rate of dry matter yield from Cyperus sp. was 7.5 g?m?2 day?1, and the nutrient uptake capacities were 21.8, 2.1, 14.0 and 0.9 g?m?2 of N, P, K and Na, respectively. Evapotranspiration (2.7 mm day?1) was statistically higher in the planted CWs. Plants in the CWs are important for achieving high nutrient removal.  相似文献   
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