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1.
A pot experiment was conducted in a plastic film house to evaluate the translocation and uptake of heavy metals(Pb,Cd,Cu,and Zn) into brown rice(Oryza sativa L.) and the heavy metals residues in soils which had previously been irrigated with domestic wastewater for a long time(3 years).The range of Pb,Cd,Cu,and Zn was 5.10 ± 0.01,0.105 ± 0.017,5.76 ± 0.42,and 23.56 ± 1.40 mg kg-1,respectively in the domestic wastewater-irrigated soil,and 0.370 ± 0.006,0.011 ± 0.001,0.340 ± 0.04,and 2.05 ± 0.18 mg kg-1,respectively,in the domestic wastewater-irrigated brown rice.The results indicated that application of domestic wastewater to arable land slightly increased the levels of Pb,Cd,Cu,and Zn in soil and brown rice(P < 0.01).The concentrations of heavy metals in brown rice were lower than the recommended tolerable levels proposed by the Joint FAO/WHO Expert Committee on Food Additives.However,the continuous monitoring and pollution control of hazardous materials from domestic wastewater are needed in order to prevent excessive build-up of heavy metals in the food chain.  相似文献   
2.
Two commercial PRRSV ELISA kits (IDEXX and Bionote) were evaluated for their sensitivityand specificity using 476 PRRS-positive serum samples collected from 7 animal challengeexperiments and 1,000 PRRS-negative sera. Both ELISA kits exhibited 100% sensitivity withsera collected 14 to 42 days post-infection, and the results from the kits were highlycorrelated (R2=0.9207). The specificity of IDEXX or Bionote kit was 99.9% or99.7%, respectively. In addition, the Bionote ELISA kit was used to examine 100 sera thatwere determined to be falsely positive either by IDEXX 2XR or 3XR ELISA, and only 7 ofthese samples were found to be positive. These results indicate that both ELISA kitsexhibited similar levels of sensitivity and specificity and would complement one anotherfor the verification of false-positive samples.  相似文献   
3.
The effect of dietary substitution of casein with fishmeal, soybean meal and crustacean meal on the growth of the abalone Haliotis discus hannai Ino was determined. A 350 g casein per kilogram diet was included into the CS diet. The whole casein was then substituted by: (1) 300 g fishmeal and 200 g soybean meal per kilogram diet (FS), (2) 200 g fishmeal, 200 g soybean meal and 130 g krill meal per kilogram diet (FSK), (3) 200 g fishmeal, 200 g soybean meal and 280 g red crab meal per kilogram diet (FSC) or (4) 200 g fishmeal, 200 g soybean meal and 130 g shrimp head meal per kilogram diet (FSS). In addition, a 50‐g by‐product of green tea per kilogram diet was included in the FS diet to form the FSG diet. Sea tangle (ST)diet was supplied to abalone as a control feed. Weight gain, final shell length and final shell width of abalone fed with the various substitution feeds (FS, FSK, FSC, FSS and FSG) were not different from those obtained with the CS diet. All the formulated feeds, however, produced higher weight gain and final shell width values than the ST diet. The results of this study show that casein can be replaced with a combination of fishmeal, soybean meal, krill meal, crab meal and/or shrimp head meal in the diet without a retardation of growth of abalone.  相似文献   
4.
The effects of feeding glucose during the 5 days before parturition on litter performance and on glucose concentration in sows were studied. At day 100 of gestation, 130 multiparous sows were assigned to the treatments. Late gestating sows were fed 0 g, 150 g, 250 g, 350 g and 450 g of glucose a day, respectively. During lactation, all sows were given free access to the same lactation diet (without glucose). One day before parturition, blood samples were collected from 30 sows (6 sows per treatment) at 10 before and 20, 40, 60 and 80 min after the meal. The supply of additional dietary glucose increased piglet birth weight ( P  < 0.05). Feed intake in week 1 and week 1–4 of lactation was greatest in sows fed the 0% glucose diet, least by sows fed the 18% glucose diet, and intermediate by sows fed the 6, 10, 14% glucose diets ( P  < 0.05). Basal glucose concentration and time of maximum glucose concentration after glucose intake were not affected by dietary treatment in the last 5 days of gestation. The sows fed the 14 and 18% glucose diets had greater maximum increase in glucose concentration than sows fed diet without glucose ( P  < 0.05). In conclusion, feeding glucose to sows during 5 days before parturition increased birth weight of live-born piglet and decreased sows feed intake during lactation, but did not affect the performance of sows and piglets.  相似文献   
5.

Objective

To evaluate the transdermal local anaesthetic effect of lidocaine or lidocaine combined with prilocaine or tetracaine in horses.

Study design

Experimental, randomized study.

Animals

A total of five healthy adult warmblood horses.

Methods

Horses were clipped bilaterally at the withers, cranial saddle area and caudal saddle area. Baseline measurements for mechanical superficial sensation via von Frey filaments and nociceptive thermal thresholds were performed. A 5% lidocaine patch (12 hour exposure, treatment L), a lidocaine/prilocaine cream (each 2.5%, treatment LP) and a lidocaine/tetracaine cream (each 7%, treatment LT) were applied (both 2 hour exposure). The same product was applied at the same location bilaterally, but on the right side an epidermal micro-perforation (dermaroller, 1200 needles) was performed prior to application. A total of five more measurements were performed at each location, immediately at the end of exposure time followed by hourly measurements. Thermal thresholds normalized to thermal excursion were analysed. One- or two-way anova and the Wilcoxon signed-rank test were used for statistical analysis with p < 0.05 considered significant.

Results

Epidermal micro-perforation had no enhancing effect. Treatments L, LP, and LT resulted in increased thermal excursion (%) immediately (84.7 ± 12.9; 100.0 ± 0.0; 100.0 ± 0.0) and 1 hour (81.7 ± 66; 86.0 ± 17.7; 87.7 ± 14.4) after the removal of the respective product compared to baseline (66.1 ± 9.3; 69.9 ± 8.3; 76.5 ± 7.8). Superficial mechanical sensation was decreased by the lidocaine-and-tetracaine cream at all time points, and by the lidocaine patch and lidocaine-and-prilocaine cream for three measurements.

Conclusions and clinical relevance

Eutectic mixtures of lidocaine with either prilocaine or tetracaine led to a reduction in thermal nociception and mechanical sensation for up to 2 hours.  相似文献   
6.
The effect of footrot on body weight and wool growth of sheep   总被引:1,自引:0,他引:1  
Body weight and traits associated with production of wool were measured over a 2-year period between 1985 and 1987 in south-western New South Wales in a flock of Merino wethers experimentally infected with footrot. The disease was allowed to spread freely amongst 150 of the flock but kept at very low prevalence in the remaining 50 by preventive footbathing during transmission periods. Severe, underrunning footrot had a significant adverse effect on body weight, for each year of the trial. Body weight was most severely reduced at times of the year when footrot was spreading among animals and lesions were severe. The mean body weight of the infected group at the end of the 2 years of observation was 7.3 kg (11.6%) below that of the control group. Footrot also depressed wool growth, with the mean clean fleece weight of the infected group being 0.4 kg (8%) lighter than that of the controls at each of the 2 annual shearings. There were no consistent differences between the groups for the other wool characteristics measured.  相似文献   
7.
The purpose of this study was to investigate how Taiwanese high‐tech firms' foreign direct investment (FDI) leads to agglomeration and competition among cities in China. By using social network analysis to analyze 1,111 subsidiaries affiliated with 270 multinational corporations (MNCs) during the years between 1988 and 2006 in 30 major Chinese cities, this study finds that: 1) agglomeration in Chinese cities falls into three primary categories: the hub cluster, the communication‐extended cluster, and the computer‐extended cluster. Among the aforementioned clusters, the hub cluster is the most critical in terms of firm location, and therefore is often a high‐priority investment site for Taiwanese high‐tech firms. 2) Chinese cities fall into four primary groups, or “blocks”: the core block, the coast block, the inland block, and the periphery block; these groups were determined by applying a structural equivalence analysis of which members of each type are in competition with one another. By linking the findings of the urban network characteristics to Chinese regional economic policies, this study provides guidance to aid executives in determining the optimal location for future FDI. Implications and suggestions for host country governments in terms of firms' investment strategies are also discussed.  相似文献   
8.
A spectral reflectance sensor(SRS) fixed on the near-surface ground was developed to support the continuous monitoring of vegetation indices such as the normalized difference vegetation index(NDVI) and photochemical reflectance index(PRI). NDVI is useful for indicating crop growth/phenology, whereas PRI was developed for observing physiological conditions. Thus, the seasonal change patterns of NDVI and PRI are two valuable pieces of information in a crop-monitoring system. However, capturing the seasonal patterns is considered challenging because the vegetation index values estimated by the reflection from vegetation are often governed by meteorological conditions, such as solar irradiance and precipitation. Further, unlike growth/phenology, the physiological condition has diurnal changes as well as seasonal characteristics. This study proposed a novel filtering method for extracting the seasonal signals of SRS-based NDVI and PRI in paddy rice, barley, and garlic. First, the measurement accuracy of SRSs was compared with handheld spectrometers, and the R~2 values between the two devices were 0.96 and 0.81 for NDVI and PRI, respectively. Second, the experimental study of threshold criteria with respect to meteorological variables(i.e., insolation, cloudiness, sunshine duration, and precipitation) was conducted, and sunshine duration was the most useful one for excluding distorted values of the vegetation indices. After data processing based on sunshine duration, the R2 values between the measured vegetation indices and the extracted seasonal signals of vegetation indices increased by approximately 0.002–0.004(NDVI) and 0.065–0.298(PRI) on the three crops, and the seasonal signals of vegetation indices became noticeably improved. This method will contribute to an agricultural monitoring system by identifying the seasonal changes in crop growth and physiological conditions.  相似文献   
9.
10.
ObjectiveTo determine the agreement of high definition oscillometry (HDO) with direct arterial blood pressure measurements in normotensive, hypotensive and hypertensive horses during general anaesthesia.Study designExperimental study.AnimalsSeven healthy warmblood horses, aged 3–11 years, weighing 470–565 kg.MethodsMeasurements from a HDO device with the cuff placed around the base of the tail were compared with pressures measured invasively from the facial artery. High blood pressures were induced by intravenous (IV) administration of dobutamine (5 μg kg−1 minute−1) over ten minutes followed by norepinephrine (0.1 mg kg−1 IV) and low pressures by increasing the inspired fraction of isoflurane and administration of nitroglycerine (0.05 mg kg−1 IV). For analysis three pressure levels were determined: high (MAP>110 mmHg), normal (60 mmHgResultsA total of 245 paired measurements of systolic (SAP), mean (MAP) and diastolic (DAP) pressures were obtained. The HDO device underestimated blood pressure at hypertensive and normotensive levels and overestimated blood pressure at hypotensive levels. Best agreement was obtained for SAP and MAP within normotensive limits. At normotension, bias ± standard deviation for SAP, MAP and DAP were 0.1 ± 19.4 mmHg, 0.5 ± 14.0, 4.7 ± 15.6, respectively. At high pressure levels bias and SD were 26.1 ± 37.3 (SAP), 4.2 ± 19.4 (MAP), 1.5 ± 16.8 (DAP) and at low pressures -20.0 ± 20.9 (SAP), -11.4 ± 19.6 (MAP), -4.7 ± 20.1 (DAP), with HDO measurements at a MAP <50 mmHg often failing.Conclusion and clinical relevanceGood agreement with invasive arterial blood pressures was obtained with HDO at normotensive levels in horses. At high and low pressure ranges HDO was unreliable. Therefore, if haemodynamic instability is expected, invasive measurement remains preferable.  相似文献   
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