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71.
The stratum corneum (SC) forms the main part of the permeability barrier of the skin. In mice and in humans, cutaneous barrier disruption can be generated by removing the SC with tape stripping (TS) and the skin barrier function can be assessed by measurement of transepidermal water loss (TEWL). The aim of the present study was to characterize the skin barrier restoration in the dog following mechanical disruption and to analyse the correlation between the skin barrier recovery and TEWL measurement. Thirty sequential TS were performed on 12 sites on four healthy beagle dogs. The number of TS was chosen to ensure a sufficient barrier disruption with a slow recovery. Skin repair was assessed for 72 h by clinical and histological examinations, and TEWL measurements. The results showed that performing 30 TS was adequate to disrupt the skin barrier in the dog. The homeostatic repair response, initiated in the skin, was rapid and characterized by complete restoration of the SC within 72 h, accompanied by greater basal cell proliferation, and dermal eosinophilic inflammation. TEWL was significantly increased by complete removal of the SC but recovered along with restoration of the SC (Scheffe test, P ≤ 0.05). Characterization of a canine model of barrier disruption and restoration and assessment of the skin barrier function by TEWL measurements could help better understand the events implied in skin barrier function. Development of this canine model is also necessary for future studies on the effects of treatments aimed at restoring the skin barrier.  相似文献   
72.
Leptospirosis is a worldwide deadly zoonotic disease. Accurate identification of the causative Leptospira spp. spirochetes ascertains the pathogenic status of the isolates, identifies potential source of infection and recognises outbreaks. Species identification is currently based on technically demanding, time and resources consuming serological and molecular methods. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) recently emerged as a first-line method for the accurate identification of bacteria, yet no data issued for Leptospira spp. We investigated the potential of MALDI-TOF-MS for the rapid identification of Leptospira isolates. Starting from a 10(5)organisms/mL suspension, MALDI-TOF-MS yielded an unique protein profile for each one of 19 Leptospira species reference isolates with a 100% reproducibility over 12 repeats, allowing to create a Leptopsira database. MALDI-TOF-MS further accurately identified 20/21 additional reference isolates representative of various serogroups at the species level as Leptospira interrogans (n=12), Leptospira kirschneri (n=5), Leptospira borgpetersenii (n=3), Leptospira noguchii (n=1) with identification score value of 2-2.5. Furthermore, six clinical isolates previously identified by rpoB sequencing, were correctly identified by MALDI-TOF-MS as L. interrogans (n=5) and L. borgpetersenii (n=1) with identification score value of 2-2.6. Identification was achieved in 40 min starting from the Leptospira suspension. MALDI-TOF-MS could complement serological and sequencing-based methods for the first line, rapid identification of Leptospira isolates in the clinical microbiology laboratory.  相似文献   
73.
The objective of this study was to compare the sedative and peripheral hemodynamic effects of acepromazine (ACP) and promethazine (PTZ) in the standing healthy horse. Nine healthy Warmblood horses randomly received either intravenous ACP at 0.1 mg/kg or PTZ at 0.1, 0.2, and 0.3 mg/kg. A sedation score based on clinical examination was recorded, and systolic arterial blood pressure was noninvasively evaluated using a Doppler flow detector at the tail, just before and every 15 minutes until 60 minutes after drug injection. Hemodynamics of the median artery of the left forelimb was studied using Doppler ultrasonography just before and 45 minutes after injection of the drug, which allowed calculation of surface (SURF), diameter (DIAM), and circumference (CIRC) of the vessel and peak systolic velocity (PSV), end diastolic velocity (EDV), mean velocity (MV), volumetric flow (VF), and resistivity index (RI) of the blood flow. Regardless of the dose used, PTZ had lesser sedative and hypotensive effects than ACP at 0.1 mg/kg and did not induce significant variations in SURF, DIAM, CIRC, PSV, EDV, MV, VF, and RI of the studied standing horses. Conversely, the vasodilatory properties of ACP were illustrated by a significant increase in SURF, DIAM, CIRC, PSV, EDV, MV, and VF and a significant reduction of the RI. Unlike ACP, PTZ did not induce alterations on the morphology of the Doppler waveform. PTZ appears to have less sedative and peripheral vasodilator effects than ACP, thus it could be safer than ACP in patients suffering from hypotension.  相似文献   
74.
Myeloperoxidase (MPO) is a pro-oxidant enzyme contained in and released by neutrophils during degranulation or after lysis. Post-thaw semen contains MPO, and concentration of this enzyme is associated with decreased motility. The aim of this study was to determine kinetics of MPO concentration during freezing, its origin, and its impact on frozen-thawed semen. Forty ejaculates were used. Semen was frozen using the classical freezing procedure. MPO concentrations were assayed in fresh semen, after centrifugation, and after cooling down to 4°C. Post-thaw MPO assay results and spermogram characteristics were determined. MPO immunocytochemistry was performed on 4 different ejaculates at each step of freezing procedure. MPO concentration increased after cooling down to 4°C and thawing compared with fresh semen. As temperature decreased, MPO was higher or tended to be higher in post-thaw poor quality samples. Nonsperm cells showed various degrees of MPO immunostaining and were observed as epithelial cells with nuclear pyknosis and keratinization. MPO immunostaining increased in medium and decreased in nonsperm cells during freezing. Our study shows that MPO concentration in equine semen increases when temperature decreases. We hypothesize that nonsperm cells present in fresh semen could release MPO.  相似文献   
75.
76.
A modified-live vaccine has been shown previously to prevent fetal infection with bovine viral diarrhoea virus (BVDV)-2 and, to some extent BVDV-1, when used in association with an inactivated vaccine in a two-step vaccination protocol. In this challenge study, the modified-live vaccine used alone was able to protect 13 heifers between 49 and 96 days of gestation at challenge from leucopenia and virus replication and, for a 4-month period, to prevent fetal infection. The efficacy of the BVDV-1f 22146/Han81 challenge was demonstrated by virus isolation from the fetuses of all nine non-vaccinated, control heifers. However, the small number of heifers tested meant that the vaccination failure rate could be as high as 10% in the field.  相似文献   
77.
Udder-thigh dermatitis (UTD) is a common disease in dairy cattle. The aim of this study was to define UTD incidence, its risk factors and the involved pathogens. Of 74 respondents, 72 (97%) reported having had the disease. On those farms the incidence was 5.3 cases per 100 cow years. The odds ratio (OR) of UTD in primiparous compared to multiparous cows was 23.4 (95% CI 17.3-33.8). Compared to tied stalls, the ORs of UTD were 0.65 (95% CI 0.45-0.92) and 0.43 (95% CI 0.24-0.71) for free stalls and straw yards, respectively. Udder oedema was reported in 98.3% of cows with UTD. The most common bacteria isolated from affected skin were Fusobacterium spp. (12/14 cases). This study suggests that UTD management should focus on local treatment, reducing udder oedema and increasing exercise.  相似文献   
78.
Spotted fever group Rickettsiae are predominantly transmitted by ticks. Rickettsiae have developed many strategies to adapt to different environmental conditions, including those within their arthropod vectors and vertebrate hosts. The tick-Rickettsiae relationship has been a point of interest for many researchers, with most studies concentrating on the role of ticks as vectors. Unfortunately, less attention has been directed towards the relationship of Rickettsiae with tick cells, tissues, and organs. This review summarizes our current understanding of the mechanisms involved in the relationship between ticks and Rickettsiae and provides an update on the recent methodological improvements that have allowed for comprehensive studies at the molecular level.  相似文献   
79.
This work focuses on a new approach to quantify the effects of above-ground earthworm's activity on soil erosion in steep slope ecosystems such as in Northern Vietnam. In these areas and in many others in the world, soil erosion becomes a major issue while the factors that determine it are still misunderstood. Earthworm's activity is believed to influence soil erosion rate, but we are still unable to precisely quantify their contribution to soil erosion. In this study, we used Near Infrared Reflectance Spectroscopy (NIRS) to quantify the proportion of soil aggregate in eroded soil coming from earthworm activity. This was done by generating NIRS signatures corresponding to different soil surface aggregates (above-ground soil casts produced by earthworms vs. surrounding topsoil).  相似文献   
80.
Recent advances in geochronology provide opportunities to identify the glacial and periglacial sequences in mountain area. In this paper, we focus on the Upper Durance catchment (Southern French Alps), in the Clarée valley, where no absolute chronological benchmark was defined. Glacial remnants and periglacial features were investigated, integrated within a chronological scenario thanks to relative (weathering rind thickness) and absolute (CRE technique) dates. We find evidence of the existence of a Late-Glacial valley glacier, that has never been reported before. Then the upper valleys became ice-free during a period corresponding to the Early-Holocene Climate Optimum, whereas two sequences of cirque glaciation are identified during the second half of the Holocene. We also show evidence of three main generations of rockglaciers, which also mainly developed during the second half of the Holocene, probably at the end of the Subboreal period. The location and the altitudes of rockglaciers are strongly dependent on the geomorphic setting (especially the location of the sediment sources), hence complicating their palaeo-climatic interpretations.  相似文献   
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