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181.
Zusammenfassung Hausbocklarven verschiedenen Gewichtes wurden in ungleich großen Abständen von der Rinde bzw. der Kerngrenze in den Splint hauptsächlich von Kiefernkantholzabschnitten verbracht. Nach mehrmonatiger Haltung unter kontrollierten Feuchtigkeits- und Temperaturbedingungen wurden der Verlauf der Fraßgänge festgestellt und — soweit es sich um Eilarven handelte — einige Ermittlungen über das Gedeihen der Tiere vorgenommen. Als Ergebnis war folgendes zu verbuchen:Die Larven waren nicht in ihrer jeweiligen Einsetzzone verblieben, sondern hatten das Splintholz regellos, aber unter gelegentlicher Bevorzugung der peripher gelegenen Schichten mit Bohrgängen durchzogen.Ein Einfluß geotaktischer Reaktionen auf die Wanderung der Larven konnte bei horizontaler Lagerung der Kanthölzer nicht eindeutig festgestellt werden.Mehrere Zentimeter tief in das Holz gesetzte Eilarven zeigten nur geringes Wachstum und hohe Sterblichkeitsziffern.Die Bedeutung der Versuchsresultate für die chemische Bekämpfung des Schädlings wird diskutiert.
Summary In experiments larvae of the house longhorn beetle were brought at different distances from the bark or the heartwood-limit into the sapwood of pine logs mainly. After a feeding period of several months the following could be stated:The larvae did not stay in the zones where they had been put in but had crossed irregularly through the whole sapwood constructing their food-galleries.Egg-larvae put into the wood to a depth of several centimeters had but a slow growth and a high mortality.The importance of the results is discussed with regard to the chemical pest control.


Die Untersuchungen erfolgten in Rahmen einer vom Bundesministerium für Wohnungswesen, Städtebau und Raumordnung dankenswerterweise finanziell unterstützten Forschungsaufgabe.  相似文献   
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A captive 16-year-old male camel (Camelus ferus bactrianus) was euthanized after a prolonged period of inappetence leading to cachexia. At necropsy, there was a 7 cm large, tan, firm, well-demarcated nodule in the tunica muscularis and serosa of the distal region of C3. Histologically, a gastric adenocarcinoma was diagnosed. Numerous metastases were found in the liver and the hepatic lymph nodes, in the wall of the portal vein and the aorta, in the lung, heart, and pleura parietalis. Osseous metaplasia was found within the pleural and aortic metastases. In the mucosa of the glandular region of the C3 compartment a diffuse marked hypertrophy of rugae resembling cerebral convolutions was observed. The lesion was characterized by glandular hyperplasia and stromal inflammation and oedema. These changes closely resembled Menétrier's disease described in humans. To our knowledge, this is the first report of concomitant metastatic gastric adenocarcinoma and gastric hyperplasia in a camel.  相似文献   
184.
Udder health problems associated with Staphylococcus aureus infections in dairy cows are difficult to control and antibiotics have limited effects. Lately, more interest has been directed towards ways to stimulate the innate immune mechanisms of the animal for better prevention and treatment of mastitis. The objectives of this study were to investigate if intramammary infusion at drying off with the immune modulator beta1,3-glucan can make the udder more resistant to experimental intra mammary S. aureus infection at this time, and to study if intramammary infusion of beta1,3-glucan into lactating udder quarters with chronic subclinical S. aureus infection can stimulate the clearing of the infection. Another aim was to evaluate the effect of beta1,3-glucan on the expression of major histocompatibility complex (MHC class II) on mammary leucocytes, measured by flow cytometry, during these circumstances. The results indicated a slight, but not statistically significant, positive effect of beta1,3-glucan at drying off on the clinical and anti-bacterial response to S. aureus infection, but no therapeutic effect of beta1,3-glucan treatment of udder quarters with chronic subclinical S. aureus mastitis. However, the proportion of MHCII+ milk lymphocytes tended to increase after glucan infusion in those udder quarters indicating a stimulation of the antigen presenting ability. To further evaluate a possible preventive effect of beta1,3-glucan infusion at drying off more studies are needed involving a larger number of animals.  相似文献   
185.
Abstract We examined 12 formalin-fixed paraffin-embedded feline skin tumours which had the histopathological features of fibropapillomas for the presence of papillomavirus (PV) DNA using touchdown polymerase chain recation (PCR), DNA sequencing and nonradioactive in situ hybridization. Nine of the tumours contained a 102-bp PCR product demonstrated using consensus PV primers that amplify a portion of the L1 gene. The nucleotide sequences are closely related, but not identical to that of ovine PV type 2, rabbit oral PV and reindeer PV. The deduced amino acid sequences had strong homologies with the major capsid protein L1 of deer PV, bovine papillomavirus (BPV) 1 and BPV 2, and European elk PV. Although PV antigens were not detected in any of the tumours by immunohistochemistry, PV DNA was demonstrated in individual mesenchymal cells or cell nests of 4/12 tumours by in situ hybridization. A nonproductive infection of mesenchymal fibroblast-like tumour cells with a papillomavirus would explain the lack of PV antigen expression and the absence of PV DNA in the hyperplastic epithelium. Because these tumours and their pathogenesis are similar to equine sarcoids, we suggest that they should be reclassified as 'feline sarcoids' instead of fibropapillomas.  相似文献   
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ABSTRACT The initial penetration process of appressoria of Colletotrichum acutatum on almond leaves was studied using digital image analysis of light micrographs and scanning electron microscopy. For image analysis, a series of sequential, partially focused digital micrographs of appressoria was analyzed to generate a single, completely focused montage image with a continuous in-focus depth of field. In studies on the development of the internal light spot (ILS), we observed that 50.4% of the appressoria formed an ILS after leaves were inoculated and incubated for 12 h at 20 degrees C, and that this increased to 95.8% after 24 h. Comparative image analyses of appressoria with and without ILSs using depth relief mapping and line profile software options showed that the ILS had a depth relief that was below that of the leaf surface. Depth relief analysis in the ILS region during incubation revealed an increase in depth in this area of up to 1.8 mum in some of the appressoria. A comparative morphological study of the ILS in montage images and the penetration pore of appressoria in scanning electron micrographs showed similar shapes and dimensions of the two structures in the appressorium. Light micrographs of histological sections confirmed fungal penetration and internal vesicle formation in almond leaves within 36 h after inoculation and incubation at 20 degrees C. This study represents the first direct evidence that the ILS in appressoria corresponds to the penetration pore and the developing penetration peg using a rapid, digital image analysis technique.  相似文献   
188.
Effect of rice growth stages and silicon on sheath blight development   总被引:1,自引:0,他引:1  
ABSTRACT The objective of this study was to determine the effect of silicon (Si) and rice growth stages on tissue susceptibility to sheath blight (Rhizoctonia solani Kühn) under controlled conditions. Rice plants (cv. Rio Formoso) were grown in pots containing low-Si soil amended with Si at 0, 0.48, 0.96, 1.44, and 1.92 g pot(-1) and inoculated with R. solani at the following days after emergence: 45 (four-leaf stage), 65 (eight-leaf stage), 85 (tillering), 117 (booting), and 130 (panicle exsertion). For plants inoculated with R. solani at all growth stages, Si concentration in straw increased as rate of Si increased from 0 to 1.92 g pot(-1). Concentration of calcium in the straw did not differ among plant growth stages. Although incubation period was not affected by the amount of Si added to the soil, this variable was shorter at booting and panicle exsertion stages. As the rates of Si increased in the soil, the total number of sheath blight lesions on sheaths and total area under the relative lesion extension curve decreased at all plant growth stages. The severity of sheath blight was lower at booting and panicle exsertion stages as the rates of Si increased in the soil. In general, plants grown in Si-nonamended pots and inoculated with R. solani were more vulnerable to infection at all growth stages, but especially at 45 days after emergence. Plant dry weights for inoculated plants increased as the Si rates increased from 0 to 1.92 g pot(-1). The greatest dry weight increases occurred for plants inoculated at booting and panicle exsertion stages. Si fertilization is a promising method for controlling sheath blight in areas where soil is Si deficient and when cultivars that exhibit an acceptable level of resistance to sheath blight are not available for commercial use.  相似文献   
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OBJECTIVE: To develop and validate an ELISA for measurement of serum canine pepsinogen A (cPG A) as a diagnostic marker of gastric disorders in dogs and to measure serum cPG A in healthy dogs after food deprivation and after feeding. SAMPLE POPULATION: Sera from 72 healthy dogs. PROCEDURE: A sandwich ELISA was developed and validated. The reference range for serum concentrations of cPG A was determined in 64 healthy dogs. Postprandial changes in serum concentrations of cPG A were evaluated in 8 healthy dogs. RESULTS: Assay sensitivity was 18 microg/L, and the maximum detectable concentration was 1,080 microg/L. The observed-to-expected ratio (O:E) for 3 serial dilutions of 3 serum samples ranged from 69.3 to 104.1%. The O:E for 3 serum samples spiked with 8 concentrations of cPG A ranged from 58.8 to 120.4%. Coefficients of variation for intra- and interassay variability of 3 serum samples ranged from 7.6 to 11.9% and from 10.1 to 13.1%, respectively. Mean +/- SD serum concentration of cPG A in healthy dogs was 63.8 +/- 31.0 microg/L and the reference range was 18 to 129 microg/L. Significant increases in serum concentrations of cPG A were observed between 1 and 7 hours after feeding. CONCLUSIONS AND CLINICAL RELEVANCE: The ELISA for measuring cPG A was sufficiently sensitive, linear, accurate, precise, and reproducible for clinical use. Serum concentrations of cPG A increase substantially after feeding, which should be taken into account when conducting clinical studies.  相似文献   
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