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31.
The neutron moisture meter (NMM) is a widely used device for sensing soil water content (SWC). Calibration accuracy and precision of the NMM are critical to obtain reliable results, and linear regression analysis of SWC against NMM count data is the most common method of calibration. In this study, artificial neural network (ANN) calibration models were developed and compared with linear regression. For this purposes, training and validation data were obtained from 2 calibration and 16 testing plots, respectively. Calibration plots consist of wet and dry soil water conditions separately. Data measured in dry beans and red pepper plots that have four different water levels were used to determine validity of regression and ANN-based calibration models. Volumetric SWC and NMM count ratio measurements were taken for depth intervals of 30 cm throughout a 120-cm-deep soil profile. Several neural network architectures were explored in order to determine the optimal network architecture. Data analyses were conducted for each soil layer and for the whole profile, separately, based on both linear regression and ANN. Linear regression calibration equation coefficients of determination (r 2) for the 0–30, 30–60, 60–90 and 90–120 cm depth ranges calculated by regression models were 0.85, 0.84, 0.72 and 0.82, respectively, and r 2 values were 0.94, 0.95, 0.87 and 0.88 based on ANN models, respectively. Using the data set from the entire 120-cm soil profile for calibration by ANN, the r 2 value was raised to 0.97.  相似文献   
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33.
Selamectin, a novel avermectin compound, was evaluated for its efficacy against naturally occurring infestations of Psoroptes cuniculi and Sarcoptes scabiei. A total of 42 New Zealand rabbits with psoroptic mange and 37 Angora rabbits with sarcoptic mange were used in the present study. On day 0, infested rabbits were treated topically with either selamectin at minimum dose of 6 mg kg(-1) (6-18 mg kg(-1) for New Zealand rabbits, n = 31 and 10-12 mg kg(-1) for Angora rabbits, n = 23) or vehicle only (control groups, n = 11 for New Zealand rabbits, n = 14 for Angora rabbits). The efficacy of selamectin was assessed both clinically and parasitologically by the presence or absence of viable mites. Rabbits were scraped for sarcoptic mites on days 7, 14, 28, 42 and 56 and had otoscopeic and/or microscopic examination for the detection of Psoroptes mites on days 7, 14, 42 and 56. Fisher's exact test was used to assess differences between the vehicle and selamectin treatment in the number of rabbits without mites (cure rates) on each assessment date. It was found that significantly fewer selamectin-treated rabbits had mites detected on skin scrapings (for S. scabiei) or otoscopeic and/or microscopic examination (for P. cuniculi) (P < 0.01) than the vehicle group. Results of the present study suggest that selamectin is effective against naturally infestations of P. cuniculi and S. scabiei in rabbits.  相似文献   
34.
OBJECTIVE: To determine the clinical efficacy of subconjunctival injection of clindamycin in the treatment of naturally occurring infectious bovine keratoconjunctivitis (IBK). ANIMALS STUDIED: Clinically, out of 81 animals examined, 46 were found to be suffering from IBK of variable severity. The ocular secretions were collected and cultured for Moraxella bovis. The study included 36 Holstein cattle from which M. Bovis was isolated. These animals ranged between 4 and 28 months of age. PROCEDURES: The severity of the clinical findings were scored as normal, mild, moderate, and severe. Clindamycin was injected subconjunctivally at a total dose of 150 mg (1 mL), once daily for 3 days to the test group (n = 18); isotonic saline solution (1 mL) was administered to the control group. After treatment, all cattle were re-examined and clinical response was evaluated on days 3, 7 and 15 post-treatment. RESULTS: Compared with the control group and prior to treatment, all active lesions such as blepharospasm, epiphora, photophobia, chemosis, corneal edema, and corneal ulceration were generally resolved by day 15 after subconjunctival injection of clindamycin. Severity of IBK lesions increased on days 3 and 7, compared to baseline in the control group administered isotonic saline solution. CONCLUSIONS: The results of this study suggest that subconjunctival injection of clindamycin is effective in the treatment of naturally occurring infectious bovine keratoconjunctivitis.  相似文献   
35.
The effect of two different diet types (concentrate feed+hay and grazing) on the pharmacokinetic profiles of triclabendazole following oral administration in goats was investigated. A total of 12 goats were randomly allocated into two groups which were either indoor and fed concentrate + hay ration (housed group) or were grazing on pasture (grazing group). Triclabendazole was administered orally to animals in two groups at 10 mg/kg bodyweight. Blood samples were collected from 1 h to 192 h post-treatment and analyzed by high performance liquid chromatography (HPLC). Feeding with different diets significantly effected the plasma disposition of triclabendazole sulphoxide. Maximum plasma concentration (C(max): 13.22+/-2.81 microg/ml), time to reach maximum plasma concentration (t(max): 18.4+/-2.19 h), area under the curve (AUC: 613+/-137 microg h/ml), half-life (t(1/2): 24.77+/-1.94 h) and mean resident time (MRT: 40.22+/-4.36 h) of triclabendazole sulphoxide in housed group were significantly different from those of grazing group (C(max): 10.17+/-1.51 microg/ml, t(max): 14.0+/-2.19 h, AUC: 406+/-98 microg h/ml), t(1/2): 16.16+/-1.17 h and MRT: 34.48+/-4.40 h). It is concluded that anthelmintically more active sulphoxide metabolite has higher plasma concentration when triclabendazole is administered to goats fed with concentrate feed + hay compared to grazing goats.  相似文献   
36.
Interactive effects of water stress and potassium (K) on some physiological attributes and nutritional status of melon (Cucumis melo L. cv. ‘Tempo F1’) plants were assessed in a pot experiment. Treatments used were: (1) control or well-watered (WW) + K1, (2) WW + K2, (3) WW + K3, (4) water stress (WS) + K1, (5) WS + K2, and (6) WS + K3. Water stress (WS) was imposed by maintaining the moisture level equivalent to 50% pot capacity, whereas well-watered (WW) pots (control) were maintained at full pot capacity (100% PC). Hoagland's nutrient solution was modified to supply K as potassium sulfate (K2SO4) at 6, 9, and 12 mM for K1, K2, and K3 treatments, respectively. Water stress reduced fruit yield, total dry matter, chlorophyll content and relative water content (RWC), but increased proline accumulation in the melon plants. However, additional supply of K as 3 or 6 mM significantly enhanced all the earlier mentioned physiological parameters, but the values were still not the same as the levels of the control treatment. Water stress also reduced leaf calcium (Ca) and K of the melon plants, but additional supply of K to the root zone increased the levels of both nutrients much higher than those at the control (C) treatment. Our study revealed that additional supply of K improved water stress tolerance in melon plants by enhancing chlorophyll, relative water content and concentrations of some essential nutrients in leaves.  相似文献   
37.
Abstract

An experiment was carried out in a controlled temperature (CT) room for five weeks with tomato cvs., Moneymaker, Liberto, and Calypso, to investigate possible relationships between zinc (Zn) deficiency or toxicity and electrolyte leakage in plant leaves. The concentrations of Zn in nutrient solution were 0.01, 0.5, and 5.0 mg L?1, respectively. There were significant reductions in the dry matter and chlorophyll content of all three cultivars grown both at 0.01 (low) and 5 mg L?1 (high) Zn compared to 0.5 mg L?1. The concentration of Zn at 0.01 mg L?1 was not sufficient to provide for optimal plant growth, while 5 mg L?1 in nutrient solution was detrimental to plant growth for all three cultivars. Dry matter production was generally lowest in the plants grown at low (0.01 mg L?1) Zn except for Moneymaker where the lowest biomass was in the high Zn treatment. Zinc concentration was increased in the leaves and roots with increasing Zn concentration in nutrient solution. Phosphorus concentration was toxic in the leaves of the plants grown at low (0.01 mg L?1) and was deficienct at high Zn (5 mg L?1). The electrolyte leakage (%) gradually increased in the plants grown at low and high Zn concentrations and these increases were greatest in the leaves of plants grown at low Zn (except for Moneymaker grown at high Zn where reduction in dry matter was less). The best results for all growth parameters tested were for the plants grown at 0.5 mg L?1 Zn. The results of this short‐term experiment show that electrolyte leakage which is relatively simple and easy to measure may be a good indicator of cultivar tolerance to Zn deficiency and toxicity.  相似文献   
38.
This, partly retrospective study, was designed to determine the seroprevalence of Schmallenberg virus (SBV), a new Orthobunyavirus first reported in Germany in late 2011, in domestic ruminants from the Middle Black Sea, West, and Southeast regions of Turkey. An indirect enzyme-linked immunosorbent assay was used to screen serum samples collected from slaughterhouse animals between 2006 and 2013. The overall seroprevalence was 335/1,362 (24.5 %) with 325/816 (39.8 %), 5/307 (1.6 %), 3/109 (2.8 %), and 2/130 (1.5 %) recorded in cattle, sheep, goats, and Anatolian water buffalo, respectively. This is the first study to demonstrate the presence of antibodies to SBV in Turkish ruminants; it indicates that cattle are more susceptible to infection than sheep, goats, or buffalo and that exposure of domestic ruminants to SBV in Turkey may have occurred up to 5 years prior to the first recorded outbreak of the disease in 2011.  相似文献   
39.
The aim of this study was to investigate effects of kefir, a traditional source of probiotic, on coccidial oocysts excretion and on the performance of dairy goat kids following weaning. Twin kids were randomly allocated to one of two groups at weaning. Kids of the first group received 20 ml of kefir daily for 6 weeks (KEF), while kids in the control group were given a placebo (CON). Individual faecal samples were regularly (n = 18 per kid) taken to quantify the number of coccidial oocysts per gram of faeces (OpG). There were no differences between the groups in terms of body weight development (P > 0.05) and feed consumption. Kids of both groups were not able to consume enough feed to meet their nutrient requirements during the first 3 weeks following weaning. KEF had a lower frequency of OpG positive samples than CON (P = 0.043). Kefir did not affect the maximum oocyst excretion and age of the kids at the highest oocyst excretion (P > 0.05). KEF shed numerically 35% lower coccidial oocysts than the controls, which corresponded to a statistical tendency (P = 0.074) in lowering Log-OpG in comparison to CON. While KEF had a lower frequency of OpG positive samples and tended to shed lower OPG by around one-third, the frequency of diarrhea, level of highest oocyst excretion, and performance of the kids remained unaffected. Therefore, it is concluded that overall effects of kefir do not have a significant impact on sub-clinical infection and performance in weaned kids under relatively high-hygienic farming conditions.  相似文献   
40.
Wild Cicer species are considered as useful genetic resources for resistance to biotic and abiotic stresses due to limited resistance in cultivated chickpeas. As a wild perennial species in the genus Cicer L., Cicer isauricum P.H. Davis is an endemic species to Turkey and endangered status according to the International Union for Conservation of Nature criteria. Here we report on its eco-geographic distribution and environmental stresses that affect the species, and advocate for its in situ and ex situ conservation. A new population of the species was discovered in Geyikbay?r?, Güllük Mountains in Antalya, Turkey. Cicer isauricum not only suffers from significant biotic stresses such as ascochyta blight [Ascochyta rabiei (Pass.) Labr.], pod borer (Helicoverpa armigera Hübner) and broomrape (Orobanche sp.), but is also subjected to drought and heat stress in its habitat. Infection with ascochyta blight in natural habitats was diagnosed by molecular techniques, and pod borer and broomrape were observed only phenotypically. PCR amplification of the internal transcribed spacer region of genomic DNA from cultured fungal isolates, yielded sequences with 100% nucleotide identity with the corresponding sequence in GeneBank for Didymella rabiei Kovachevski (anamorph: A. rabiei). The pathogen may have co-evolved with C. isauricum in the newly discovered site. Because C. isauricum is exposed to drought and accompanying heat stress in its natural habitat, it appears able to tolerate heat stress up to 45 °C during podding stage and terminal drought in late summer from its woody, deep rooting. C. isauricum bears multiple flowers per axil, a potentially useful trait in cultivated chickpea. In conclusion, C. isauricum is a potential genetic source for resistance to biotic and abiotic stresses, in need of greater protection due to its endangered status.  相似文献   
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