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51.
Irrigation of crops in arid regions with marginal water is expanding. Due to economic and environmental issues arising from use of low-quality water, irrigation should follow the actual crop water demands. However, direct measurements of transpiration are scant, and indirect methods are commonly applied; e.g., the Penman–Monteith (PM) equation that integrates physiological and meteorological parameters. In this study, the effects of environmental conditions on canopy resistance and water loss were experimentally characterized, and a model to calculate palm tree evapotranspiration ETc was developed. A novel addition was to integrate water salinity into the model, thus accounting for irrigation water quality as an additional factor. Palm tree ETc was affected by irrigation water salinity, and maximum values were reduced by 25 % in plants irrigated with 4 dS m?1 and by 50 % in the trees irrigated with 8 dS m?1. Results relating the responses of stomata to the environment exhibited an exponential relation between increased light intensities and stomatal conductance, a surprising positive response of stomata to high vapor pressure deficits and a decrease in conductance as water salinity increased. These findings were integrated into a modified ‘Jarvis–PM’ canopy conductance model using only meteorological and water quality inputs. The new approach produced weekly irrigation recommendations based on field water salinity (2.8 dS m?1) and climatic forecasts that led to a 20 % decrease in irrigation water use when compared with current irrigation recommendations.  相似文献   
52.
AIM: To describe the microscopic and immunohistochemical findings in a case of pulmonary hyalohyphomycosis in a Kemp's ridley sea turtle (Lepidochelys kempi). METHODS: Samples of lung, liver and kidney from a stranded, dead Kemp's ridley sea turtle were routinely processed for histopathological studies. Two monoclonal antibodies that reacted specifically with antigens of Aspergillus spp and the Mucorales (Zygomycetes) group, and a panel of polyclonal antibodies raised against Aspergillus fumigatus, Candida albicans, Geotrichum candidum, Fusarium solani, and Scedosporium apiospermum were used for immunohistochemical or immunofluorescence staining. RESULTS: Histologically, a severe multifocal granulomatous pneumonia associated with fungal infection was diagnosed. All hyphae were identified as Fusarium spp because a strong and uniform reactivity was obtained only with a heterologously-absorbed polyclonal antibody raised against somatic antigens of Fusarium solani. CONCLUSIONS: Fusarium spp should be included in the differential diagnosis of mycotic pneumonia in Kemp's ridley sea turtles. CLINICAL RELEVANCE: This is the first report of a pulmonary mycotic infection in a sea turtle diagnosed using immunohistochemistry. Wildlife rehabilitators and pathologists should be aware of the availability of immunohistochemical techniques for identifying fungi in sea turtles.  相似文献   
53.
Digestive lesions were observed in 84 of 136 sea turtles (128 Caretta caretta, four Chelonia mydas and four Dermochelys coriacea) stranded in the Canary Islands between January 1993 and December 2001. In the oral cavity ulcerative and necropurulent stomatitis were the most frequently observed lesions, and in the oesophagus ulcerative and fibrinous oesophagitis, and traumatic oesophageal perforation were most frequently observed; all these lesions were mainly associated with the ingestion of fishing hooks. Different histological types of gastritis were observed in 35 of the turtles; necropurulent and fibrinous gastritis were associated with bacterial infections caused mainly by Proteus species, Vibrio alginolyticus, and Staphylococcus species, and larval nematodes of the genus Anisakis were responsible for a form of parasitic gastritis observed in 16 of the turtles. Different histological types of enteritis, including catarrhal, fibrinous, necropurulent and necrotising enteritis, affected 36 turtles; a wide range of gram-negative and gram-positive bacteria, including Bacillus species, Escherichia coli, Pasteurella species, Proteus species, Staphylococcus species, Streptococcus species and V. alginolyticus, were isolated from these lesions. All the cases of necrotising enteritis were associated with intestinal intussusception caused by the ingestion of monofilament fishing lines. Necrotising and/or multifocal granulomatous hepatitis were the lesions most commonly observed in the liver; they affected 29 of the turtles and were associated with Aeromonas hydrophila, Citrobacter species, E. coli, Proteus species, Staphylococcus species and V. alginolyticus infections. According to the stranding reports and the gross and histological lesions observed, 33 of the turtles had digestive lesions associated with the ingestion of hooks and monofilament lines, and two had lesions associated with the ingestion of crude oil.  相似文献   
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A cutaneous melanocytoma-acanthoma in a 2-year-old female German Shepherd Dog was characterized by the presence of two populations of neoplastic cells: epithelial and melanocytic. The epithelial component consisted of nests of well-differentiated stratified squamous epithelium closely associated with neoplastic melanocytes. The epithelial cells immunoreacted with both monoclonal and polyclonal anti-cytokeratin antibodies, and immunoreaction to S-100 protein and vimentin was observed in the melanocytic cells. This rare pigmented skin neoplasm of the dog apparently has a benign behavior.  相似文献   
56.
A morphologic classification based on the cytochemical characteristics of blood cells of 35 juvenile loggerhead sea turtles (Caretta caretta) is described. Cytochemical stains included benzidine peroxidase, chloroacetate esterase, alpha-naphthyl butyrate esterase (with and without sodium fluoride), acid phosphatase (with and without tartaric acid), Sudan black B, periodic acid-Schiff, and toluidine blue. The morphologic characteristics of erythrocytes were similar to those reported in green turtles. Six types of white blood cells were identified: heterophils, eosinophils, basophils, lymphocytes, monocytes and thrombocytes. Except for the basophils, the rest of the white blood cells from loggerhead turtles had different cytochemical characteristics compared to blood cells from other sea turtle species. The leukocyte differential count was different from that reported for other sea turtle species. Heterophils were the most numerous leukocytes from these loggerhead turtles, followed by lymphocytes, eosinophils, monocytes and basophils. This paper provides a morphologic classification of blood cells of loggerhead sea turtles that is useful for veterinary surgeons involved in sea turtle conservation.  相似文献   
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Eggs high in n-6 PUFA, predominant in Western markets, were found to increase blood LDL oxidation, suggesting a new health concern beyond raising cholesterol. Protective composition was explored by increasing egg antioxidants and MUFA and reducing n-6 PUFA. Lag times to plasma LDL oxidation were significantly shortened with two eggs/day of high-PUFA compositions compared to a low-egg (2-4/week) regime, by 28.8% following "HPUFA-regular" ( p < 0.01) and by 27.2% following antioxidant-fortified "HPUFA-HAOX" ( p < 0.01). However, two "HMUFA-HAOX" eggs/day with reduced egg n-6 PUFA FA% (LA by 30.7%) and PUFA:MUFA ratio (LA:OA by 45.8%) plus increased antioxidants (vitamin E 500%, carotenoids 260%), resulting in increased plasma OA 33.3%, vitamin E 22.4%, and carotenoids 55.0% ( p < 0.01), were associated with lag-time only 6.6% shorter than low-egg (NS). Among health-oriented egg modifications, here for the first time they reduced associated LDL oxidization, consistent with anti-inflammation and antioxidant paradigms, warranting further research on functional advantages of antioxidative egg composition.  相似文献   
59.
The stability of the cyclopropane ring and the fatty acid composition of microbial cells were determined using chlorotrimethylsilane as reagent with three different conditions 80 degrees C for 1 h, 60 degrees C for 1 h, and 60 degrees C for 2 h. Chlorotrimethylsilane permits a simultaneous extraction and derivatization of fatty acids. A basic method was used as reference. The bacteria, Escherichia coli, Burkholderia cepacia, and Lactobacillus brevis, and fungi Aspergillus niger and Gibberella fujikuroi were used. The stability of the cyclopropane ring on acidic conditions was tested using the cyclopropanecarboxylic acid and a commercial mixture of bacteria fatty acid methyl esters (BAME). Fisher's least significant difference test showed significant differences among the methods. The method using chlorotrimethylsilane and 1-pentanol for 1 h at 80 degrees C gave the best results in cyclopropane, hydroxyl, and total fatty acid recoveries. This procedure allows the fast and easy one-step direct extraction derivatization.  相似文献   
60.
Genetic parameters and selection responses were obtained for harvest body weight of blue tilapia (Oreochromis aureus) from data collected over three generations in a selected population. A total of 18 194 records representing 186 sires and 201 dams were used in the analysis. Within generation heritability estimates for harvest body weight ranged from 0.18 to 0.58. When data from more than one generation were included in the analysis, heritability estimates became more stable (0.33–0.40) and it was 0.33 when all data were included in the analysis. The common full‐sib effect accounted for 10% of the phenotypic variance in the full data set. Heritability for survival from stocking to harvest was estimated at 0.01 and 0.09 in actual units (fitting an animal model) and in the logit (sire model) scale respectively. The genetic correlation between harvest body weight and survival was 0.22 and not significantly different from zero. The total selection response for harvest body weight over the three generations of selection measured as the difference between least‐squares means of selected and control lines was 17.7%. The corresponding figure when response was measured as the difference between mean breeding values of selected and control lines was 19.6%. The average inbreeding coefficient was 0.003 after three generations of selection. These results indicate that there are good prospects for the genetic improvement of harvest body weight in blue tilapia.  相似文献   
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