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91.
92.
We investigated the dynamics of porcine reproductive and respiratory syndrome virus (PRRSV) variability in a range of swine PRRS-positive farms located in Northern Italy, to provide insights into the epidemiology and diffusion of the virus, particularly throughout the entire swine production chain. In this context, we also examined the effectiveness and the critical points of a recently developed gilts acclimatization program in swine breeder farms. To achieve these aims, we designed new primers and determined 64 complete open reading frame 5 (ORF5) sequences, representing Italian PRRSV field strains and the European vaccine Porcilis strain (Intervet); in addition, the more conserved ORF7 of 11 PRRSV strains were sequenced. The domains' prediction of their putative protein sequences was performed as well. Based on these sequences, phylogenetic trees were inferred which revealed a high degree of variability among the PRRSV Italian strains. The outcomes of the phylogenetic analysis showed that the most frequent source of infection in PRRS-positive farms (sow herds, nursery sites, fattening units) was the introduction of animals carrying a new variant and not the modification of already present variants; moreover, the integration of data from phylogenetic analysis and from the clinical and serological status of the swine herds suggested that the acclimatization program could be a valid tool to stabilize the PRRS clinical picture in farms, only when applied in combination with rigorous bio-security routine management and avoid the incoming of new PRRSV variants.  相似文献   
93.
Regular consumption of tomato and its products is being consistently associated with lower risk of several types of cancer and, to a lesser extent, coronary heart disease. Among the many tomato components credited with healthful properties, carotenoids and particularly lycopene are being actively investigated. Given the recognized role of immune/inflammatory processes in atherogenesis, the effects of a tomato-based drink (Lyc-o-Mato), which was previously shown to afford DNA protection from oxidative stress, on the modulation of immune and inflammatory markers (by enzyme immunoessay), on basal lymphocyte DNA damage (by comet assay), and on F2-isoprostane excretion (by LC-MS/MS), were investigated in 26 healthy young volunteers. In a placebo-controlled, double-blind, crossover study, Lyc-o-Mato (5.7 mg of lycopene, 3.7 mg of phytoene, 2.7 mg of phytofluene, 1 mg of beta-carotene, and 1.8 mg of alpha-tocopherol) or a placebo drink (same taste and flavor, but devoid of active compounds) were given for 26 days, separated by a wash-out period. During the study subjects maintained their habitual, hence unrestricted, diet. TNF-alpha production by whole blood was 34.4% lower after 26 days of drink consumption, whereas the other parameters were not significantly modified by the treatment. In turn, modest effects of the regular intake of a tomato drink, providing small amounts of carotenoids, were found on the production of inflammatory mediators, such as TNF-alpha, in young healthy volunteers. Future intervention trials in subjects with low carotenoid status and/or compromised immune system will resolve the issue of whether carotenoids modulate immune parameters in humans.  相似文献   
94.
Herpesviral infections frequently occur in horses. The objective of this study was to investigate the possible association of equine herpesviruses (EHV-1, EHV-2, EHV-3, EHV-4, EHV-5) with other causes of abortion, neonatal mortality or placental disorder. Sixty-seven abortions, 22 stillbirths, 14 cases of neonatal foal mortality and 3 cases of placental disease were investigated for infectious and non-infectious causes. Type-specific nested PCR assays and virus isolation were performed to detect EHV infections. A cause of fetal loss or placental disease was reached in 68 out 116 (58.7 %) cases. Twenty-seven cases were positive for EHV, and 22/27 (81.5 %) were positive for EHV-1 (16 neuropathogenic and 6 non-neuropathogenic strains), 4 (14.8 %) for EHV-2 and 3 (11.1 %) for EHV-5. The association between EHV infections and other etiological agents was statistically significant (two sided P?=?0.002). The odds ratio of EHV DNA associated with other diagnoses, especially with bacterial infection and premature placental separation, was 10.88 (95 % confidence interval: 2.15–55.16). EHV-1 was the main viral cause of pregnancy loss in this study, also associated with other etiological agents, including EHV-2 and EHV-5. The latter viruses in particular need to be more fully investigated to elucidate what role either or both may play as co-infecting agents with other established infectious causes of reproductive disease.  相似文献   
95.
Lagovirus is an emerging genus of Caliciviridae, which includes the Rabbit Hemorrhagic Disease Virus (RHDV) of rabbits and the European brown hare syndrome virus (EBHSV) of hares that cause lethal hepatitis. In 2010, a new RHDV related virus (RHDV2) with a unique genetic and antigenic profile and lower virulence was identified in France in rabbits. Here we report the identification of RHDV2 as the cause in Sardinia of several outbreaks of acute hepatitis in rabbits and Cape hare (Lepus capensis mediterraneus). This is the first account of a lagovirus that causes fatal hepatitis in both rabbits and hares.  相似文献   
96.
Small ruminant lentivirus (SRLV) belonging to the highly divergent genotype E has recently been identified in the Italian goat breed Roccaverano. In this report we have developed a specific serological test based on recombinant matrix/capsid antigen fusion protein. Performance has been evaluated and compared with a similar test based on genotype B antigen. Herds under study were selected according to the infectious status characterized by blood PCR and sequencing. Results clearly showed that B and E based recombinant ELISA only detected homologous infection and an apparent cross-reactivity was recorded in a herd in which co-infection was present. Three commercially available ELISAs showed different abilities in detecting genotype E infection, being the whole virus-based immunoassay the best choice. Genotype E-recombinant antigen was not detected in ELISA by three commercially available Mabs known to be cross-reactive among CAEV and MVV capsid antigens, further supporting the high divergence of the E genotype from others. Finally, a SRLV-free herd according to commercial ELISA testing, was analysed in the same area where genotype E was identified and few animals belonging to Roccaverano breed were found slightly reactive with the E antigens. Our results suggest that the prevalence of genotype E in other small ruminant populations may be conveniently estimated using a comparative assay based on a combination of genotype specific recombinant antigens and may highlight a wider space in which SRLVs evolve.  相似文献   
97.
Background: The rat is used often to assess the toxicity of new chemical entities in preclinical drug development. Bilirubin concentration in rat serum is routinely determined by colorimetric methods, but false positive results due to hemolyzed serum or direct interferences by test compounds may occur. Capillary electrophoresis (CE) is an automated method that requires small sample volume and facilitates the direct detection of bilirubin. Objective: The purpose of this study was to evaluate a CE method for detecting bilirubin and albumin‐bound bilirubin in rat serum and to measure potential interference by hemolysis and specific test compounds. Methods: Serum samples from male Sprague Dawley rats (n=20) were used in the study. Results obtained on a Beckman P/ACE MDQ CE instrument equipped with a UV‐detector were compared with those obtained using a colorimetric method on a Hitachi 912 analyzer. Bilirubin standards were used to evaluate the detection and stability of bilirubin in rat serum, and vials with ultrafiltration membranes were used to separate albumin‐bound bilirubin. Intraday and interday coefficients of variation (CV), linearity, and the effects of added hemoglobin and a test compound on CE results were determined. Results: The CE method was capable of detecting bilirubin and albumin‐bound bilirubin in rat serum samples with reproducible results and good accuracy. CVs were <3% and linearity of the CE assay was high (R2=0.9951). Abnormally high bilirubin peaks due to the presence of hemoglobin or the test compound were easily distinguished by means of CE. Conclusion: CE is a good alternative to the colorimetric methods currently used for the determination of bilirubin in rat serum.  相似文献   
98.
Colletotrichum gloeosporioides is the causal agent of Camellia oleifera anthracnose, mainly infecting fruits and leaves. The fungus secretes degrading enzymes to destroy the cuticle of aerial plant parts and help infect the host successfully. To validate whether a cutinase gene (CglCUT1) was required for cutinase activity and pathogenicity of C. gloeosporioides, the CglCUT1 gene was cloned and analyzed. The characterization of CglCUT1 predicted protein suggests that the cloned DNA encoded a cutinase in C. gloeosporioides affecting C. oleifera. The CglCUT1 showed a high homology to those from C. gloeosporioides causing papaya anthracnose and C. capsici causing pepper anthracnose, as well as those of other ascomycetes. The whole CglCUT1 gene was knocked-out and the knockout mutant (?CglCUT39) was subsequently complemented using Agrobacterium tumefaciens mediated transformation. The knockout transformants exhibited significant decreases in cutinase activity and virulence compared with the wild-type strain. The complemented transformants of the disrupted transformant ?CglCUT39 showed a significant increase in cutinase activity and virulence compared with the disrupted transformant ?CglCUT39. This study suggests that the CglCUT1 gene has a positive effect on fungal virulence of the hemibiotrophic C. gloeosporioides on C. oleifera.  相似文献   
99.
One of the most used thermal treatments in potatoes to inactivate enzymes and prevent their oxidation is the boiling process. This treatment significantly decreases the taste of the potato and causes “off-odours” during storage, whatsoever, represents a big problem for the production of potato-based foodstuffs. This study focused on evaluating the sensory profile of potato slices subjected to a boiling process of three Mexican potato varieties (Alpha, Chica and Gallo) and on off-odours detection in potato produced during storage. According to the examined parameters through PanelCheck, the trained panel had a good performance, resulting 8 of the 12 attributes evaluated were significant. The formation of “cardboard-like off-odour” was detected in the Alpha and Chica varieties at the 24 and 33 h of storage, respectively. Chica potato presented this off-odours with at level significantly lower than Alpha potato (about 30% lower). With respect of Gallo variety, this presented different oxidation olfactory perceptions described by the assessors as “burnt note”, detected after 5 h of refrigerated storage. An adequate election of the variety of potato according to processing will allow an effective utilization of this vegetable and the obtention of potato-based foodstuffs much more stable.  相似文献   
100.
Corynebacterium urealyticum is an uncommon cause of urinary tract infections in cats. However, it is difficult to diagnose and if left untreated it may result in irreversible bladder lesions. C urealyticum is a multiantibiotic-resistant bacterium whose culture requires special care. Risk factors for the occurrence of this infection include urological procedures, foreign bodies, bladder mucosa abnormalities, immuno-suppressed states and antibiotic treatment. This report describes an unusual case of C urealyticum urinary infection in a young cat with pre-existing urethral obstruction. C urealyticum was isolated in pure cultures from two urine samples. Clinical and ultrasound features, results of the urinalysis and urine culture are described as well as therapeutic treatment and eventual favourable outcome to treatment with amoxycillin-clavulanic acid.  相似文献   
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