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191.
The amnion is a layer of the foetal membrane that has mechanical protection function and allows expansion and growth. The diseases that affect amnion have rarely been reported in horses. Amnionitis and funiculitis have been implicated as components of abortions as observed in abortions caused by the mare reproductive loss syndrome. Here, we report an abortion at 240-day gestation of a 7-year-old Anglo-Arabian mare with a history of previous stillbirth. Blood samples from both mare and foetus were collected for serological testing. Fragments from the placenta were taken for macroscopic and histopathological examinations. The results of these tests ruled out leptospirosis and concluded that the cause of the abortion was non-infectious chronic amnionitis. Moreover, the decreased vascularization in the placenta was consistent with placental insufficiency. This case highlights the importance of monthly ultrasound monitoring in equine pregnancy in order to diagnose placental insufficiency. The study also confirmed the efficiency of the histopathological examination for the definitive diagnosis of placental inflammation and for the study of foetal vascularization to rule out placental insufficiency in equine reproduction.  相似文献   
192.
Differences in soil P among silvopasture, grassland, and arable lands have been well established. Nevertheless, most of the reports compare soil properties under long‐term sites. Thus, there exists little information on the effect of the conversion of silvopasture to arable or grassland use on soil P pools. The objective of the study was to determine the impact of converting silvopasture system (SP) into arable cropping and grassland system on the distribution of P pools and potential P bioavailability. We compared the following systems: SP system, SP converted to arable cropland (SP‐AL), SP converted to grassland (SP‐GL), and for comparative purposes, a long‐term arable cropland (AL). The P fractionation was performed by a sequential extraction scheme, using acid and alkaline extractants on samples collected from the 0–10 and 10–20 cm soil layers. It was assumed that the large variations in soil‐P fractionations are caused by the different management practices associated with land conversion. The results of P fractionation showed a dominance of calcium‐bound P, HCl‐extractable Pi constituted up to 36% of the soil total P (TP). However, the type of land use did not affect this P fraction. On the other hand, the reduction in labile‐Pi and NaOH‐Pi fractions observed at the SP‐AL site may have led to the decline in readily available P. The soil total organic P (TPo) content was 8% and 17% lower at SP‐AL compared to SP and SP‐GL site, respectively. Labile organic‐P (labile‐Po) content was markedly higher at SP site compared to arable soils, and was ≈ 10% of TPo. The NaOH‐Po constituted the highest fraction of the organic‐P pool (55%–79% of TPo) across all the study systems, and was positively correlated with TPo (p < 0.01). The study indicates that conversion of SP system in temperate regions to arable cropping with conventional tillage seems to result in the reduction of P availability compared to SP, indicating SP as an important land‐use practice.  相似文献   
193.
In Bos taurus cattle, antimullerian hormone (AMH) has been demonstrated to have a high degree of correlation with ovarian antral follicle count and the number of healthy follicles and oocytes. To document the correlation between the plasma concentration of AMH and follicular number in Bos indicus and Bos taurus heifers, Nelore (Bos indicus, n = 16) and Holstein heifers (Bos taurus, n = 16) had their ovarian follicular waves synchronized. After synchronization, ovarian antral follicular population (AFP) was evaluated three times at 60‐day (d) intervals (T‐120 d, 120 days before plasma AMH determination; T‐60 d, 60 days before; and T0, at the time of plasma AMH determination). The plasma AMH concentration was positively correlated with the number of ovarian follicles on the day of the follicular wave emergence in Bos indicus (Nelore) and Bos taurus (Holstein) heifers at each evaluation time (p < 0.05). The AFP was higher in Bos indicus (Nelore) than in Bos taurus (Holstein) heifers (p < 0.05). Similarly, the AMH concentration was higher in Bos indicus (Nelore) than in Bos taurus (Holstein) heifers (p < 0.0001). When heifers were classified as to present high or low AFP according to the mean of the AFP within each genetic group, high‐AFP heifers presented a greater (p < 0.0001) AMH concentration than low‐AFP heifers, regardless of the genetic group. In conclusion, the AFP is positively correlated with plasma AMH concentration in both Bos indicus (Nelore) and Bos taurus (Holstein) heifers. Furthermore, Bos indicus (Nelore) heifers presented both greater plasma AMH concentrations and AFP than Bos taurus (Holstein) heifers.  相似文献   
194.
The aims of this study were to characterize EGF protein expression in ovine ovaries and to verify the effect of EGF on the in vitro development of isolated pre‐antral follicles. After collection, ovarian tissue was fixed for immunohistochemical analysis. Additional pairs of ovaries were collected, and secondary follicles were cultured for 18 days in α‐MEM+ (control) alone or supplemented with EGF (1, 10 or 50 ng/ml). The immunostaining for EGF was observed in oocytes from pre‐antral and antral follicles, in granulosa cells of primary and secondary follicles, as well as in cumulus and mural cells of antral follicles. After 18 days, the results showed that treatment with 50 ng/ml EGF significantly increased the percentage of morphologically normal follicles compared with the control group (α‐MEM+) and significantly reduced the precocious extrusion of oocytes and increased the percentage of antral follicles compared with the control and 1 ng/ml EGF. All the treatments induced a progressive and significant increase of the follicular diameter throughout the period of culture. However, there were no significant differences in follicular diameter or in the daily growth rate among treatments. In conclusion, this study demonstrated the presence of EGF in ovine ovaries. Moreover, 50 ng/ml EGF increased the percentage of normal follicles and improved antrum formation in isolated ovine follicles after 18 days of in vitro culture.  相似文献   
195.
Three potentially valuable red seaweeds, Chondrus crispus Stackhouse, Gracilaria bursa pastoris (S.G. Gmelin) P.C. Silva and Palmaria palmata (L.) O. Kuntze, collected in northern Portugal, were cultivated using the nutrient-rich effluents from a local turbot (Scophthalmus maximus Linnaeus) and sea bass (Dicentrarchus labrax Linnaeus) farm. The algae were cultivated in a two level cascade system. Several arrangements of the cascade system, stocking densities (3, 5, 7 and 8 kg m− 2) and water fluxes (140 and 325 l h− 1) were tested to optimize biomass yield and nitrogen uptake rate and efficiency. The yield and the total ammonium nitrogen (TAN) uptake of the three species were highly seasonal. Palmaria could not survive culture conditions during the summer when water temperature was above 21 °C. In the spring, Palmaria had an average yield of 40.2 (± 12.80) g DW m− 2 day− 1 and a nitrogen uptake efficiency (NUE) of 41.0% (± 17.26%). NUE expresses, in percentage, the average reduction in TAN concentration between the inflows and the outflows of the tanks. Chondrus performed better in summer with an average yield of 37.0 (± 11.10) g DW m− 2 day− 1 and removing 41.3% (± 17.32%) of nitrogen. Gracilaria grew year round, but also performed better during spring/summer, producing an average of 29.1 (± 2.90) g DW m− 2 day− 1, and only 7.3 (± 5.08) g DW m− 2 day− 1 during autumn. Yield of C. crispus did not differ significantly when grown at two different stocking densities (5 kg m− 2 and 8 kg m− 2). On the other hand, Gracilaria had significantly higher yields at 5 than at 7 kg m− 2. Better NUE, on average 76.7% (± 22.13%), was also obtained with 5 kg m− 2 stocking density and only 63.8% (± 24.62%) with 7 kg m− 2. The yield of Gracilaria increased significantly with the increase of water flux from 140 to 325 l h− 1 and more nitrogen was removed from the water. However, NUE decreased from 48.4% to 33.4% at 140 and 325 l h− 1, respectively. Biofiltration was highly improved by a cascade system with a NUE as high as 83.5%.  相似文献   
196.
Inter-simple-sequence repeat (ISSR) were used to fingerprint three kinds of F1 interspecific hybrids: the Portuguese durum wheat cultivar ‘Candial’ × tritordeum, the Portuguese bread wheat cultivar ‘Barbela’ × tritordeum and the Portuguese triticale cultivar ‘Douro’ × tritordeum. Among the 30 primers tested, the number of discriminative primers varies from 13 to 20 in each hybrid combination, the total number of ISSR loci analysed ranged from 101 to 183, and the number of discriminative ISSR loci varied from 50 to 71. ISSR-PCR technique revealed to be a valuable fingerprint system for all F1 hybrid combinations and respective parents analysed here. The complementary use of molecular cytogenetic techniques and molecular markers could allow a more accurately evaluation and characterisation of different plant species.  相似文献   
197.
The IGF system is related to embryo quality. We aim to determine the effect of the heat stress on the mRNA expression of IGF1 and IGF2, IGFR1 and IGFR2, IGFBP2 and IGFBP4, and PAPPA in in vitro production (IVP) blastocysts from Nelore and Holstein after ovum pick up (OPU) to better understand the differences between these breeds. Oocytes from four Nelore and seven Holstein were collected in six OPU sessions. Following in vitro maturation and fertilization using six Nelore or Holstein sires, embryos were divided into control (cultured at 39°C) and heat stress (HS; exposed to 41°C for 9 h). Blastocysts were submitted to RNA extraction. The IGF1 expression was higher in blastocysts under HS in both breeds, and the expression of IGFBP2 and IGFBP4 was higher in Holstein blastocysts under HS. The high PAPPA expression and the low expression of IGFBP2 and IGFBP4 are associated with a more efficient degradation of IGFBPs, which results in greater IGF bioavailability in Nelore blastocysts and may contribute to the superior HS tolerance in Nelore, when compared to Holstein.  相似文献   
198.

Purpose

Determination of reservoir volume has been used in the calculation of sedimentation, hydrodynamic modelling, and dam safety assessment, among others, and the method used as well as its associated error play an important role in the quality of these studies. This study assessed the accuracy of reservoir volume calculations based on different standards for the definition of the spacing between bathymetric range lines. A technique for terrain modelling and a method for determining the survey accuracy are also proposed.

Materials and methods

The reference reservoir volume was based on highly detailed bathymetry (10 m resolution). Seven different spacings were selected, which generated 99 separate bathymetric data sets. For each data set, the volume was calculated based on a digital terrain model according to the usual model (triangular irregular network (TIN)) and according to the insertion of mesh points (IMP) method. This was then compared with the reference volume, and the accuracy of each survey was determined.

Results and discussion

Utilization of a highly detailed and reliable bathymetric survey allowed for the assessment of the associated error in each of the bathymetric data sets, as well as of the spacing standards analyzed. The accuracy of the standards analyzed using TIN modeling ranged from 0.31% to 14.40% (30 and 300 m, respectively). The high errors are attributed to the limitation of the TIN in representing regions near shores, producing incorrect shallow depth readings, resulting in a lower calculated volume than the real volume. IMP modeling exhibited great improvement in performance over the standard TIN (i.e., for 300 m accuracy of 5.51% for IMP and 14.40% for standard TIN), and in none of the cases were the generated volumes greater than the reference volume.

Conclusions

The IMP method proved to be consistent, improving quality of the data while reducing effort in field work. The low accuracies found showed that even surveys following the widely accepted standards contain errors of a magnitude that cannot be ignored. Thus, knowing and evaluating the survey accuracy is of fundamental importance. Definition of standard spacing for reservoirs proved to be unfeasible. This must be defined on a case-to-case basis, considering the error acceptable for the purpose of the survey.  相似文献   
199.
Anemon I is a new monitoring system that can be used to evaluate autonomic nervous system reactivity in real time by showing a simple, easily interpretated quantitative index (0–200), the Anemon Index (AI) ( Junke et al. 2000 ). This study used the AI to evaluate the quality of analgesia during sevoflurane and fentanyl anaesthesia in pigs. Six healthy pigs, weighing 24.76 ± 3.40 kg, were induced to anaesthesia with 5% sevoflurane (SEVO) in 5 L minute?1 oxygen. After endotracheal intubation SEVO was given at 1 MAC (2.66%) in 3 L minute?1 oxygen. Fentanyl was infused IV at 50 µg kg?1 hour?1 for the first 30 minutes of anaesthesia, discontinued for 30 minutes, and then infused at 100 µg kg?1 hour?1 for another 30 minutes. Three mechanical noxious stimuli (needle prick, pin‐prick and pressure on the abdomen) were applied for 15 seconds at 30, 60 and 90 minutes. The AI, ECG, invasive mean arterial blood pressure (MAP), heart rate (HR), SpO2 by pulse oximetry, tidal volume, Fe′sevo , Fe ′CO2 and respiratory rate were recorded before induction (baseline), after induction, after intubation and extubation, and before and during noxious stimulation at 30, 60 and 90 minutes. Recovery times were recorded. Statistically significant differences were determined by anova . Spearman rank‐correlation was used to evaluate the relationship between AI and hemodynamic variables. A p‐value of < 0.05 was considered significant. A significant (p < 0.01) decrease in AI was recorded after anaesthetic induction, from 82.3 ± 21.1 to 52.7 ± 20.3. After intubation, AI increased slightly, but not significantly, to 71.7 ± 27.1. A significant (p < 0.05) increase of AI occurred after extubation. Nociceptive stimuli did not have any measurable effect either on AI or on recorded cardiovascular variables. There was no movement, respiratory changes, or any other visible response to noxious stimulation. The AI did not change significantly with the different doses of fentanyl. Respiratory depression and apnoea were seen in all animals during the fentanyl infusion; therefore, pigs received intermittent positive pressure ventilation. Anaesthesia with sevoflurane and fentanyl resulted in a significant (p < 0.001) decrease in MAP. Heart rate did not change significantly. There was no correlation between AI and cardiovascular variables (HR and MAP). Endotracheal intubation caused an increase and extubation a greater significant increase in the AI. This suggests that intubation and extubation may represent stressful events during general anaesthesia, although further studies are needed to validate the use of the AI in pigs. Sevoflurane anesthetic induction may not prevent the sympathetic stimulus caused by endotracheal intubation in pigs, as indicated by the increased AI values.  相似文献   
200.
Land pollution due to past mining activities is a major environmental issue in many European countries. The Aljustrel mine (SW Portugal), located in the western sector of the Iberian Pyrite Belt (IBP) presents a negative visual and environmental impact as a consequence of the mining activity that has developed since the Roman era. Its impacts are also a restraint on the life quality of the population. The exposure of pyrite and other sulphides to air are responsible for the pollution observed in soils, surface water and stream sediments. This paper investigates the pollution load of potential toxic elements in soil samples collected around the Aljustrel mining area. The aim is to assess the levels of soil contamination with respect to average concentrations of toxic elements in the region and to understand the partitioning and availability of pollutants in the area. The results showed severe soil contamination (mainly As, Cd, Cu, Pb and Zn). The concentrations of As (up to 3936 mg kg−1) and certain heavy metals (up to 5414 mg kg−1 Cu, 61·6 mg kg−1 Cd, 20 000 mg kg−1 Pb and 20 000 mg kg−1 Zn) are two orders of magnitude above the regional South Portuguese Zone (SPZ) background values. The median concentrations of As, Cd, Cu, Pb and Zn exceed the values established for world soils, the European Union, Portugal and Andalusia. The results suggest that the distribution patterns of Co, Cr and Ni element concentrations in the Aljustrel area are primarily influenced by the lithology and geochemistry nature of bedrock. The soil background of this geological domain is characterized by relatively high heavy metal contents, essentially derived from the parent rocks. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
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