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61.
A 7-month-old intact female German shepherd dog was presented with recurrent urinary tract infections and incontinence, ambiguous external genitalia (enlarged vulva containing a penis), and an anovestibular fistula. Anatomical structures, histopathology, and karyotyping supported a diagnosis of female pseudo-hermaphrodite, hypothesized to be a result of in utero androgenization with consequential cloacal malformation.  相似文献   
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Sub-adult individuals of Aporrectodea caliginosa were incubated for 16 weeks under laboratory cultures in a soil treated with 0%, 10% or 50% of a Populus nigra half-decomposed leaves, respectively. Growth was maximum in the 50% organic matter treatment and cocoon production occurred. Average soil ingestion rates decreased from 1.56 g/g?1 fresh weight of worm per day?1 in control soil to 1.17 and 0.5 g, respectively, in treatments with 10% and 50% half-decomposed litter. Surface casts never comprised more than 10% of total cast production. Near-infrared spectrometry (NIRS)signatures of digested and non-ingested soil significantly differed and showed a rather constant effect of digestion, independent of the organic matter content (p?<?0.01). These results confirm the value of NIRS spectral signatures as indicators of the origin of soil aggregates and biological processes involved in soil aggregation.  相似文献   
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This study assessed ecological and socio-economic impacts of a participatory forest management project in the Republic of Benin. The study focused on the Wari-Maro Forest Reserve and the ‘Projet d’Aménagement des Massifs Forestiers’ five years after its completion. A forest inventory was carried out using 37 square plots of 729 m2 each to characterise the population structure of two types of plantations established: plantations with exotic species and plantations with native species. In addition, individual surveys were conducted with local households, organs of joint forest management and forestry officers to evaluate their perceptions about the participatory management of the plantations. Finally, the sustainability of the participatory management was assessed with an established rating system. Results showed that plantations with exotic species were more successful than plantations with native species. Local communities argued that they have not been involved in the plantations design but only in the implementation step and that their standards of living have decreased after the project completion. The rating system used showed that the participatory management of plantations had a short-term sustainability. The findings suggest that future projects should be designed and implemented with better participation of local communities as full partners.  相似文献   
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A cross-sectional study was conducted on dairy farms in eight milking centres in Trinidad to determine the prevalence of risk factors for mastitis and to assess their relationship to occurrence of subclinical mastitis. The California mastitis test (CMT) was used to determine the prevalence of subclinical mastitis by estimating the somatic cell counts in bulk and composite milk. Of a total of 177 dairy farms studied, 121 (68.4%), 39 (22.0%) and 17 (9.6%) practised semi-intensive, extensive and intensive management systems, respectively. A total of 129 (72.9%), 37 (20.9%) and 11 (6.2%) farms milked cows in parlours, stanchions and pasture/out-on-field, respectively. Based on sanitary practices, 40 (22.6%), 123 (69.5%), and 14 (7.9%) farms were classified as good, fair, and poor, respectively, while 76 (42.9%) and 60 (33.9%) farms reported to rarely experience and frequently experience water shortages, respectively. Amongst the 177 farms, only seven (4.0%) used machine-milking primarily, 152 (85.9%) screened for mastitis as a routine, 18 (10.2%) teat dipped, and 49 (27.7%) practised dry cow therapy. To detect mastitis, of 152 farms involved, 20 (13.2%) used the strip cup while only two (1.3%) employed the CMT. Pipe-borne water delivered directly from the hose was the only source of water to 91 (51.4%) farms while seven (4.0%) and eight (4.5%) farms used only well and surface water (ponds and rivers), respectively. Based on bulk milk samples, the farm prevalence of subclinical mastitis was 60.5% (107 of 177) with a range from 33.3% (centre 5H) to 100.0% (centre 2B). The difference was statistically significant (P < 0.01; chi 2). However, using composite milk, the farm prevalence of subclinical mastitis was 52.5% (93 of 177) with a range from 21.2% (centre 5H) to 92.9% (centre 2B) and again, the difference in prevalence was statistically significant (P < 0.001; chi 2). Subclinical mastitis was detected in 150 (45.0%) of 333 lactating cows screened and the range of prevalence was from 17.9% (centre 5H) to 56.3% (centre 1C). The difference was statistically significant (P < 0.001; chi 2). Of a total of 14 risk factors for mastitis studied which were related to animal husbandry, personnel, mastitis control and water, only two, the herd size and practice of dry cow therapy were significantly (P < 0.05; chi 2) associated with subclinical mastitis. It was concluded that the high prevalence of subclinical mastitis in Trinidad dairy herds could significantly reduce milk production with associated economic loss. Although a majority of the risk factors studied were not found to be significantly associated with the occurrence of subclinical mastitis possibly due to confounding factors, the need to eliminate or reduce these risk factors cannot be over-emphasized.  相似文献   
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BACKGROUND: Intestinal hypoperfusion can lead to increased lactate concentrations in plasma and peritoneal fluid of horses with colic. HYPOTHESIS: The purposes of this study were to (1) evaluate the reliability of the Accusport analyzer to assess peritoneal fluid lactate (PFL) concentrations in healthy horses and those with colic, (2) identify clinical features associated with abnormal blood plasma lactate (BPL) and PFL concentrations, and (3) evaluate the prognostic value of BPL and PFL. ANIMALS: BPL and PFL were determined in 20 healthy horses and in 106 horses with colic. RESULTS: The Accusport was reliable for determining BPL concentrations < 13 mM and PFL concentrations < 20 mM. Multivariate analysis indicated that PCV and the need for intestinal resection were independently associated with the BPL; pulse, PCV, venous pO2, the presence of necrotic intestine, an increased amount of peritoneal fluid, and fluid total protein content were independently associated with PFL. With a 1 mM increase in BPL or PFL, the respective odds ratios for required abdominal surgery increase to 1.23 (BPL) and 1.58 (PFL), odds ratios for a required intestinal resection increase to 1.20 (BPL) and 1.41 (PFL), and odds ratios for developing ileus increase by 1.33 (BPL) and 1.36 (PFL). PFL concentrations of 1, 6, 12, and 16 mM correspond to a probability of death of 11, 29, 63, and 82%, respectively, in horses without strangulating obstruction and of 25, 52, 82, and 92%, respectively, in horses with strangulating obstruction. CONCLUSION: PFL is more useful and sensitive than BPL for prognostic purposes in horses with colic.  相似文献   
67.
A deeper phylogeographic structure is expected for slow-dispersing habitat specialists compared to widespread adaptable species, especially in topographically complex regions. We tested this classic assumption by comparing the genomic (RAD-sequencing) phylogeographies of 2 amphibians inhabiting the Swiss Alps: the mobile, cosmopolitan common frog (Rana temporaria) against the stationary, mountain endemic Alpine salamander (Salamandra atra). Our results ran opposite of predictions: the frog displayed significantly higher genetic divergences and lower within-population variation compared to the salamander. This implies a prominent role for their distinctive glacial histories in shaping intraspecific diversity and structure: diversification and recolonization from several circum-Alpine micro-refugia for the frog versus a single refugium for the salamander, potentially combined with better population connectivity and stability. These striking differences emphasize the great variability of phylogeographic responses to the Quaternary glaciations, hence the complexity to predict general patterns of genetic diversity at the regional scale, and the forces that underlie them.  相似文献   
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  • ? We examined the relationships between productivity, leaf traits and carbon isotope discrimination in bulk leaf matter (Δ1) and in phloem sap (Δs) from more than 5-year-old trees belonging to Populus deltoides × P. nigra and Populus trichocarpa × P. deltoides; trees were grown in alluvial and non alluvial sites in a commercial poplar plantation.
  • ? On both sites, a large genetic variability was evidenced for all variables. The genotypic ranking remained stable between years for all variables, while it differed between sites. Δ1 scaled positively with Δs and neither Δ1 nor Δs were correlated with productivity. A significant genotype by site interaction was evident for all variables. The non alluvial site resulted in lower productivity, and in thicker/denser leaves with lower nitrogen and carbon contents. Noteworthy, the genotypic ranking for Δ1 measured at the alluvial site was similar to that previously established in a glasshouse.
  • ? As observed in previous studies from younger trees, there is a potential to select genotypes, combining high productivity and high water-use efficiency, for growth in moderately drought-prone areas.
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