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61.
Objective: To determine whether in healthy horses and those with colic, exposure of peritoneal fluid to room air affects values obtained on biochemical analysis. Study Design: Prospective study. Animals: Adult horses with a primary complaint of acute abdominal pain (n=29) and 12 healthy horses. Methods: Peritoneal fluid was aseptically collected under aerobic and anaerobic conditions. After collection, pH, PCO2, PO2, HCO3?, Na+, ionized Ca2+, K+, lactate, and glucose were immediately measured using a commercial blood gas analyzer. Biochemical variables were compared between aerobically and anaerobically obtained samples using a paired t‐test. Results: In healthy horses, peritoneal fluid samples collected under anaerobic conditions had higher PCO2 and ionized Ca2+ and lower PO2, HCO3?, and pH compared with samples exposed to air. No differences were observed for K+, Na+, glucose, and lactate. In horses with colic, samples collected anaerobically had higher PCO2, ionized Ca2+, Na+, and glucose and lower PO2, HCO3?, and pH value compared with samples exposed to air. No differences were observed for K+ and lactate. Conclusion: Exposure of peritoneal fluid to room air had a significant effect on pH, PCO2, PO2, and variables associated or dependent on changes in pH such as HCO3? and ionized Ca2+. Interpretation of biochemical analysis of peritoneal fluid may be influenced by sample collection method.  相似文献   
62.
Quality protein maize (QPM) has approximately twice the tryptophan (Trp) and lysine (Lys) concentrations in protein compared to normal maize. Because several genetic systems control the protein quality of QPM, it is essential to regularly monitor Trp and/or Lys in breeding programs. Our objective was to examine the potential of near-infrared reflectance spectroscopy (NIRS) to enhance the efficiency of QPM research efforts by partially replacing more expensive and time-consuming wet chemistry analysis. More than 276 maize samples were used to develop NIRS models for protein content (PC), Trp, and Lys. The standard error of prediction (SEP) for the calibration and the coefficient of determination for validation (R(2)(v)) were 0.26 and 0.96 for PC, 0.005 and 0.85 for Trp, and 0.02 and 0.75 for Lys. When the NIRS models were used to evaluate 266 S2 lines from five QPM breeding populations, the coefficients of determination between NIRS and the chemical data were 0.94, 0.76, and 0.80 for PC, Trp, and Lys, respectively. Therefore, the NIRS models can be used to support the QPM breeding efforts.  相似文献   
63.
ABSTRACT: Several animal models have been established to study visceral leishmaniosis (VL), a worldwide vector-borne disease affecting humans and domestic animals that constitutes a serious public health problem. BALB/c mice and Syrian hamsters are the most widely used experimental models. In this paper, we summarize the advantages and disadvantages of these two experimental models and discuss the results obtained using these models in different studies of VL. Studies using the BALB/c mouse model have underscored differences between the liver and spleen in the course of VL, indicating that pathological evaluation of the visceral organs is essential for understanding the immune mechanisms induced by Leishmania infantum infection. The main goal of this review is to collate the relevant literature on Leishmania pathogenesis into a sequence of events, providing a schematic view of the main components of adaptive and innate immunity in the liver and spleen after experimental infection with L. infantum or L. donovani. This review also presents several viewpoints and reflections about some controversial aspects of Leishmania research, including the choice of experimental model, route of administration, inoculum size and the relevance of pathology (intimately linked to parasite persistence): a thorough understanding of which is essential for future VL research and the successful development of efficient control strategies for Leishmania spp.  相似文献   
64.
OBJECTIVE: To determine whether a customized solution could attenuate the effects of low-flow ischemia and reperfusion injury of the equine jejunum. SAMPLE POPULATION: A segment of jejunum obtained from 21 healthy adult horses. PROCEDURE: A segment of jejunum was maintained in an isolated extracorporeal circuit, and arterial flow was reduced to 20% of baseline for 40 minutes (ischemia) followed by 60 minutes of reperfusion. In 1 group, a customized solution was infused at a rate of 1 ml/min during low-flow ischemia and 3 ml/min during reperfusion. In a second group, the solution was infused at the same rate during low-flow ischemia, but it was infused at a rate of 7 ml/min during reperfusion. Control groups received lactated Ringer's solution administered at the same rates as for the customized solution. Various metabolic, hemodynamic, histologic, and permeability variables were recorded. RESULTS: A lower flow rate during reperfusion (3 ml/min) had a beneficial effect, compared with lactated Ringer's solution or the higher flow rate (7 ml/min). Use of the solution at this rate resulted in less histomorphologic injury and reduced mucosal permeability to albumin. CONCLUSIONS AND CLINICAL RELEVANCE: Use of a customized solution at a lower flow rate during repurfusion appeared to have a protective effect on equine jejunum when administered IV during low-flow ischemia and reperfusion.  相似文献   
65.
A comparative study of canine testicular tumors in descended and cryptorchid testes was performed in order to associate pathologic features with clinical signs. Observation on 80 canine testicular tumors revealed the following distribution: in undescended testes, 4 tumors were classified as Seminomas (mean age: 8.8 +/- 3 years) and 14 as Sertoli cell tumors (8.7 +/- 1.7 years); in descended testes, 21 tumors were classified as seminomas (8.8 +/- 3 years), 13 as Sertoli cell tumors (9.8 +/- 1.8 years), 22 as Leydig cell tumors (11.5 +/- 2 years), 5 multiple primary tumors and 1 as an immunoblastic lymphoma. Histological features were studied and correlated with other clinical parameters: feminization manifestations, prostatic disease, perineal hernia and perianal gland tumor.  相似文献   
66.
Tegaserod, a serotonin agonist, has been shown to have prokinetic effects in horses, but pharmacokinetic information is not currently available. The pharmacokinetics and in vitro effects of tegaserod were evaluated. Tegaserod increased the contractile activity of smooth muscle preparations of the equine pelvic flexure. Pertinent pharmacokinetic parameters for a single IV and oral dose were determined. Therapeutic plasma concentrations of tegaserod were achieved by a single oral dose at 0.27 mg/kg. These findings indicate that further clinical studies are warranted to investigate potential benefits in cases of functional gastrointestinal motility disorders in horses.  相似文献   
67.
In vitro susceptibilities of 16 Mycoplasma mycoides subsp. mycoides large colony type field isolates to 15 antimicrobial agents were determined using a broth microdilution method. The most effective antimicrobials were fluoroquinolones, tetracyclines and macrolides, with MIC values under 2 microg/ml. Resistance to nalidixic acid, gentamicin, streptomycin and spectinomycin was observed.  相似文献   
68.
Abstract

The main objective of this work was to determine whether nitrogen-use efficiency was affected by the application of different forms (iodide vs iodate) and dosages (20, 40 and 80 µM) of iodine, to ascertain the influence of this trace element in a biofortification programme in lettuce plants. The parameters analysed were root and shoot biomass, nitrate concentration, and organic and total nitrogen as well as those defining nitrogen-use efficiency in plants: total nitrogen content, total nitrogen accumulation, nitrogen-uptake efficiency and nitrogen-utilization efficiency. In addition to decreasing shoot biomass, iodide treatments reduced leaf levels of nitrates, organic nitrogen, and total nitrogen content. Iodate treatments did not affect the concentration of nitrogen in its different forms. The application of iodide caused total nitrogen accumulation and nitrogen-uptake efficiency to decrease, iodate application improved the latter. Both iodide and iodate applications significantly improved nitrogen-utilization efficiency in comparison to the control. The results obtained show that iodate application rates of 40 µM or lower significantly improved all nitrogen parameters analysed, making it possible to increase lettuce productivity and quality.  相似文献   
69.
Data from a divergent experiment for birthweight (BrW) environmental variability were used to estimate genetic parameters for BrW trait and its environmental variability by fitting both homoscedastic (HO) and heteroscedastic (HE) models. A total of 5 475 records of BrW from animals born from inbred dams, and 7 140 pedigree records were used. The heritability of BrW using the model HO was 0.27, with the litter effect much more important, 0.43. The model HE provided a genetic correlation between the trait and its environmental variability that was very high and negative, ?0.97, and a high value for the additive genetic variance for environmental variability, suggesting an artefact in the model. The residual skewness was found to be essentially null. A model considering the genetic correlation null was also fitted, and used to obtain the breeding values for the selection process. Moreover, the trait was considered as maternal resulting in similar estimates under the model HO, but more reasonable for the genetic correlation between the trait and its environmental variability of 0.48 with a value of 0.25 for the additive genetic variance regarding environmental variability under the model HE. This led to the conclusion that environmental variability of BrW in mice must be selected via dams. Estimated parameters in a reduced dataset without inbred animals did not substantially change this conclusion.  相似文献   
70.
Electrical resistivity tomography (2D ERT) is a powerful tool for the diagnosis of the subsoil state and to pursue an environmental monitoring in time to detect and follow a temporal evolution of plumes in hydrocarbon-contaminated soils. In situ, 2D ERT was conducted to investigate the electrical properties of the subsoil in three petrol stations in Murcia semiarid Region (SE Spain), which have been active for many years, in order to look for anomalous areas that could be related to the presence of a non-aqueous phase liquid (NAPL) contaminant plume in the subsoil. A total of 18 ERT profiles in wet and dry season were conducted to study the seasonal effects in the resistivity values of the subsoil. Dipole?Cdipole array was set up to make the soil diagnosis, achieving a good vertical and lateral resistivity distributions for the sites investigated. Interpretations obtained from ERT pseudo-sections, after a processing and inversion data process with PROSYS II and RES2DINV software, show delimited highly resistive regions above 2,000 ??·m at 2?m deep related to the underground storage tanks (USTs) position and the filling ports and anomalous resistivity areas where boreholes and further GC?CFID determination in soil samples have been done. No significant differences have been found between results obtained in dry and wet seasons. Thus, the geo-electrical non-destructive technique ERT is presented as a tool to delineate the USTs positions and to point out anomaly in the subsoil that could contain NAPL, helping to design sampling strategies, saving cost and time.  相似文献   
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