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61.
Canine herpesvirus‐1 (CHV‐1) is known to be associated with fertility and fecundity disorders as well as neonatal mortality in puppies of less than 3 weeks of age. The virus is presumed to be enzootic in dogs all over the world and recent studies in several European countries suggest a high seroprevalence among the dog population. In the year 2000, a total of 647 Belgian canine sera from 102 privately owned patients and 545 breeding dogs were analysed with an enzyme‐linked immunosorbent assay (ELISA). Furthermore 77 of the samples were submitted to two serum neutralization (SN) tests for comparison. An overall CHV‐1 seroprevalence of 45.75% was observed in the Belgian dog population. No significant differences could be observed based on breeding status, reason for consultation or sex. The correlation between the ELISA and both SN tests appeared to be moderate with a significantly greater sensitivity of the ELISA. This study also demonstrated that the CHV‐1 seroprevalence in the Belgian dog population is similar to that in other recently investigated European countries and that the incidence in breeding units is not necessarily higher than in non‐breeding dogs.  相似文献   
62.
Ten South American sea lions (Otaria flavescens) were presented for clinical evaluation and diagnosis of tuberculosis following known exposure to Mycobacterium pinnipedii. CT was used to determine whether foci of calcification in mediastinal lymph nodes, typically associated with pinniped tuberculosis, could be detected and whether CT was a useful diagnostic modality, in conjunction with other tests, for the diagnosis of tuberculosis in this species. Blood was collected from the caudal gluteal vein of each animal for serological testing using commercially available serological tests (ElephantTB STAT-PAK and DPP Vet; Chembio Diagnostic Systems) and a multiantigen print immunoassay (MAPIA), carried out at Chembio to verify the in-house kits. In four of nine animals that underwent CT scanning, lesions consistent with pinniped tuberculosis were apparent and these were confirmed at subsequent postmortem examination. The five remaining animals did not show any abnormalities on CT, with three being negative on serological tests, which were considered to be normal and potentially used as reference images for healthy sea lions. One animal could not be CT scanned due to its large size and weight (510 kg).  相似文献   
63.
Silicon (Si) reduces arsenic (As) levels in rice shoot and grain. However, the underlying mechanisms remain unclear. In this study, we examined the effect of Si application to three rice paddy soils on the dynamics of Si, iron (Fe), phosphorus (P), and As in the soil solution, As accumulation in rice straw, flag leaf, husk, brown rice, and polished rice, and on As speciation in polished rice. Silicon application to soil increased the concentrations of Si, Fe, As, and P in the soil solution, while the redox potential was unaffected. Arsenic concentrations of straw, flag leaf, and husk were reduced by half by Si application, while As concentrations of brown and polished rice were decreased by 22%. The main As species in polished rice was arsenite, As(III), with a fraction of 70%, followed by dimethylarsinic acid (DMA) and arsenate, As(V), with 24% and 6%, respectively. Silicon application to the soil did not affect DMA or As(V) concentration of polished rice, while the As(III) concentration was reduced by 33%. These results confirm that Si reduces As(III) uptake and translocation into the shoot. Furthermore, data indicate that decrease of As concentration of polished rice is due to decreased As(III) transport into grain. Possible underlying mechanisms are discussed.  相似文献   
64.
65.
Precisely detecting oestrus is important for artificial insemination. The aims of this study were to identify oestrus‐specific sow mucus proteins to determine the optimal time for artificial insemination. The proestrous‐ and oestrous‐stage mucus proteins were purified and analysed with proteomic tools such as two‐dimensional gel electrophoresis and matrix‐assisted laser desorption/ionization–time‐of‐flight analyses. Among the differentially expressed proteins, the dimethylarginine dimethylaminohydrolase 2 (DDAH2) protein showed a 3.6‐fold increase during the proestrous stage compared to that during the oestrous stage. A western immunoblot study revealed that two of three sow mucus samples clearly showed negative anti‐DDAH2 antibody activity during the oestrous stage. This study demonstrated that the pig DDAH2 mucus protein exists during the proestrous stage, but not during the oestrous stage, suggesting that mucus DDAH2 could be useful as an oestrus detection marker.  相似文献   
66.
Abstract

CASE HISTORY: Outbreaks of mortality in South Island saddlebacks (Philesturnus carunculatus carunculatus) that had been translocated to two offshore islands in the Marlborough Sounds of New Zealand were investigated during the summer of 2002 and 2007. Both outbreaks were associated with a severe decrease in numbers of saddlebacks of up to 60% of approximately 200 birds.

CLINICAL AND PATHOLOGICAL FINDINGS: Many of the surviving birds were in poor condition, and had skin lesions on the legs and head. Necropsy showed pale liver and lungs, and a swollen spleen. Histopathology revealed schizonts resembling Plasmodium spp. within the cytoplasm of many hepatocytes and splenic histiocytes. The skin lesions consisted of epithelial proliferations containing numerous Bollinger bodies typical of avipox virus (APV) infection. Two different APV were isolated, using PCR, from two different birds exhibiting skin lesions. Each isolate had 100% sequence homology with APV members from either Clade A or Clade B. In addition, PCR analysis revealed that the Plasmodium elongatum present in infected birdsbelonged to a strain that was endemic in the population of North Island saddlebacks (Philesturnus carunculatus rufusater).

DIAGNOSIS: Concurrent infections with Plasmodium spp. haemoparasites and APV were identified as the likely cause of death in the birds examined.

CONCLUSIONS AND CLINICAL RELEVANCE: Although the Plasmodium spp. identified is thought to be endemic to saddlebacks in New Zealand, the affected birds were likely to be immunocompromised by concurrent APV infection or through lack of genetic diversity. Both the introduced mosquito Culex quinquefasicatus and the native mosquito Culex pervigilans are likely vectors for both these diseases, and the provision of water supplies less favourable to mosquito-breeding is recommended.  相似文献   
67.
Summary

The fertilizer nitrogen (N) inputs to some vegetables such as cauliflower (Brassica oleracea var. botrytis) can be large. One approach to decreasing the input of N may be to select for cultivars efficient in the use of nitrogen. The objective of this investigation was to identify a cultivar which was nitrogen efficient in terms of producing a high yield under nitrogen (N) limiting conditions. Field trials were conducted in 1993 and 1994 with the cauliflower F1-hybrids (B..oleracea var. botrytis) `Marine', `Lindurian' and `Linford' at the Ruthe (Germany) and Schermer (the Netherlands) sites. Optimum N supply was 250 kg ha21 as the sum of the inorganic N content of the soil (Nmin) at planting and fertilizer N. Limiting N supply consisted of Nmin at planting and mineralization of N during cultivation. The Nmin at planting was 116 and 66 kg ha21 at Ruthe and 84 and 20 kg ha21 at Schermer in 1993 and 1994, respectively. The yield in terms of total dry-matter and quality (measured as percentage class 1 curds) was highest with `Marine' both at limiting and optimum N supply. Additionally, in quality `Marine' was the least sensitive variety to N shortage. Thus, `Marine' could be regarded as being nitrogen efficient. `Linford' could be considered as nitrogen inefficient in quality, whereas `Lindurian' generally performed inconsistently. The reduction in quality with N shortage was due to an increase in loose curds, indicating that limiting N supply promoted the process of bolting. Quality defect buttoning increased in part with N shortage. `Marine' produced no buttoned curds. Bracting was not affected by N supply and appeared only in Ruthe 1994 with `Lindurian' and `Linford'. It was concluded that the improved efficiency with `Marine' in terms of total dry matter and quality might have been achieved either through a higher N uptake capacity of the root system (uptake efficiency) and/or through a greater utilization of nitrogen by the plant (N utilization efficiency).  相似文献   
68.
The reasons for this prospective experimental study were to determine a dosing scheme with loading and maintenance dose of aspirin inducing inhibition of platelet function measured by whole blood impedance aggregometry. Ten horses received aspirin orally in the morning with one loading dose of 4.7–5 mg/kg and maintenance doses of 1–1.3 mg/kg daily the following 4 days. Aggregometries (COLtest, ASPItest, ADPtest) and serum salicylic acid were measured. ASPItest showed significant difference in inhibition at 24 and 48 hr (p < .05) and 96 hr (p < .01). Significant change for ADPtest and COLtest couldn't be detected. Serum salicylic acid concentrations were significantly (p < .01) increased at 6 and 12 hr. Despite this, three horses failed any inhibitory effect of platelet function, suspecting an aspirin resistance. Regarding the other seven horses platelet aggregation induced by ASPItest was reduced between 37% and 100% from baseline at 6 and 12 hr and between 0 and 98% during the next 4 days. Correlations of serum concentration of salicylic acid and aggregometries couldn't be detected. It can be presumed that equine platelets are less susceptible to aspirin what may compromise eventually the anticoagulatory effects and efficacy in preventing and treating diseases with increased platelet activation as endotoxaemia or laminitis.  相似文献   
69.
Potato (Solanum tuberosum L.), an important food crop, generally requires a high amount of phosphate fertilizer for optimum growth and yield. One option to reduce the need of fertilizer is the use of P‐efficient genotypes. Two efficient and two inefficient genotypes were investigated for P‐efficiency mechanisms. The contribution of root traits to P uptake was quantified using a mechanistic simulation model. For all genotypes, high P supply increased the relative growth rate of shoot, shoot P concentration, and P‐uptake rate of roots but decreased root‐to‐shoot ratio, root‐hair length, and P‐utilization efficiency. Genotypes CGN 17903 and CIP 384321.3 were clearly superior to genotypes CGN 22367 and CGN 18233 in terms of shoot–dry matter yield and relative shoot‐growth rate at low P supply, and therefore can be considered as P‐efficient. Phosphorus efficiency of genotype CGN 17903 was related to higher P‐utilization efficiency and that of CIP 384321.3 to both higher P‐uptake efficiency in terms of root‐to‐shoot ratio and intermediate P‐utilization efficiency. Phosphorus‐efficient genotypes exhibited longer root hairs compared to inefficient genotypes at both P levels. However, this did not significantly affect the uptake rate and the extension of the depletion zone around roots. The P inefficiency of CGN 18233 was related to low P‐utilization efficiency and that of CGN 22367 to a combination of low P uptake and intermediate P‐utilization efficiency. Simulation of P uptake revealed that no other P‐mobilization mechanism was involved since predicted uptake approximated observed uptake indicating that the processes involved in P transport and morphological root characterstics affecting P uptake are well described.  相似文献   
70.
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