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71.
Seed zones for forest tree species are a widely used tool in reforestation programs to ensure that seedlings are well adapted to their planting environments. Here, we propose a climate-based seed zone system for Mexico to address observed and projected climate change. The proposed seed zone classification is based on bands of climate variables often related to genetic adaptation of tree species: mean coldest month temperature (MCMT) and an aridity index (AHM). The overlay of the MCMT and AHM for the 1961–1990 period resulted in 63 climate-based zones. Climate change observed over the last three decades has resulted in an increase of + 0.74 °C for MCMT and a shift toward overall drier conditions across Mexico. By the 2050s, MCMT is expected to increase by + 1.7 °C and AHM shifts further towards drier conditions. We recommend moving seed sources from warm, dry locations towards currently wetter and cooler planting sites, to compensate for climate change that has already occurred and is expected to continue for the next decades. We contribute a straight-forward climate-based seed zone system that allows practitioners to match seed procurement regions with planting regions under observed and anticipated climate change. Our transfer recommendations using climate-based zones can be implemented within the existing seed zone system, which often span large climate gradients.  相似文献   
72.
Abstract

Swedish long-term soil fertility experiments were used to investigate the effect of texture and fertilization regime on soil electrical conductivity. In one geophysical approach, fields were mapped to characterize the horizontal variability in apparent electrical conductivity down to 1.5 m soil depth using an electromagnetic induction meter (EM38 device). The data obtained were geo-referenced by dGPS. The other approach consisted of measuring the vertical variability in electrical conductivity along transects using a multi-electrode apparatus for electrical resistivity tomography (GeoTom RES/IP device) down to 2 m depth. Geophysical field work was complemented by soil analyses. The results showed that despite 40 years of different fertilization regimes, treatments had no significant effects on the apparent electrical conductivity. Instead, the comparison of sites revealed high and low conductivity soils, with gradual differences explained by soil texture. A significant, linear relationship found between apparent electrical conductivity and soil clay content explained 80% of the variability measured. In terms of soil depth, both low and high electrical conductivity values were measured. Abrupt changes in electrical conductivity within a field revealed the presence of ‘deviating areas’. Higher values corresponded well with layers with a high clay content, while local inclusions of coarse-textured materials caused a high variability in conductivity in some fields. The geophysical methods tested provided useful information on the variability in soil texture at the experimental sites. The use of spatial EC variability as a co-variable in statistical analysis could be a complementary tool in the evaluation of experimental results.  相似文献   
73.
The aim of the study was to elucidate the distribution and possible transmission routes of Toxocara spp. infection in Estonia. Out of 454 faecal and sand samples collected from park lawns and sandpits in the town of Tartu, 19 were Toxocara positive (4.2%). Out of the 45 sandpit samples 17.8% were Toxocara positive. Cat faeces was found in 21 sandpit samples. Parasitological necropsies were performed on 41 euthanised stray dogs and 27 cats in the Tallinn Dog Home. Additionally, 13 wild free-roaming brown rats (Rattus norvegicus) were captured from the Tallinn Dog Home territory, necropsied and studied for the presence of Toxocara larvae. Toxocara canis adults were found in 14.6% of the dogs and Toxocara cati (syn. mystax) adults in the small intestines of 48.2% of the cats examined. Larval infection was detected in the kidney and liver in 5 dogs (12.2%). Our study demonstrated only low-level larval Toxocara infections in adult dogs. Toxocara larvae were not found in cats and brown rats. According to the results of this study, cats more often carry Toxocara infection than dogs. Under our conditions, stray and free-roaming cats are the main contaminators of the environment with Toxocara eggs. Children playing in sandpits are the main risk group for larval toxocarosis.  相似文献   
74.
Speltoid spikes are characterized by pyramidal spike morphology featuring an elongated rachis and tenacious glumes. Speltoids are considered undesirable spike aberrants in wheat breeding leading to increased heterogeneity within a cultivar candidate. As a consequence, the presence of speltoids may result in rejection of a cultivar candidate during official field trials or denial of cultivar certification during seed multiplication. A reliable method is, thus, required to assess the occurrence of speltoids, early on in a wheat breeding program. The domestication gene Q located on the long arm of wheat chromosome 5A is known to suppress the speltoid phenotype in wheat. Here, a quantitative pyrosequencing assay was developed to distinguish between normal wheat plants, which possess two copies of the Q allele, and aberrants, which are either aneuploids lacking the correct number of chromosome 5A copies or plants which carry the primitive q allele. An accurate and reproducible determination of the Q gene copy number was achieved for different wheat genotypes based on homoeologous sequence quantification with two primer combinations at the Q locus. Single plants with one to four copies of the Q allele could be detected by quantitative pyrosequencing which corresponded to the occurrence of speltoid (1 Q allele), normal (2 Q alleles), and compact (more than 2 Q alleles) spikes. Q and q specific alleles could be differentiated at SNP position 2299 of the Q gene. This SNP is assumed to be related to the emergence of free-threshing wheat forms. To our knowledge this is the first report for detection of aneuploids and differentiation of Q alleles in bread wheat using pyrosequencing technology. In future, quantitative pyrosequencing assay can be applied in wheat breeding programs to carry out marker-assisted selection against the presence of speltoid spike aberrants.  相似文献   
75.
The idea of food sovereignty has its roots primarily in the response of small producers in developing countries to decreasing levels of control over land, production practices, and food access. While the concerns of urban Chicagoans struggling with low food access may seem far from these issues, the authors believe that the ideas associated with food sovereignty will lead to the construction of solutions to what is often called the ??food desert?? issue that serve and empower communities in ways that less democratic solutions do not. In Chicago and elsewhere, residents and activists often see and experience racial and economic inequalities through the variety of stores and other food access sites available in their community. The connections between food access, respect, and activism are first considered through a set of statements of Chicagoans living in food access poor areas. We will then discuss these connections through the work and philosophy of activists in Chicago centered in food sovereignty and food justice. Particular focus will be placed on Growing Power, an urban food production, distribution, and learning organization working primarily in Milwaukee and Chicago, and Healthy South Chicago, a community coalition focused on health issues in a working class area of the city.  相似文献   
76.
Novel mutant alleles of an ethylene receptor Solanum lycopersicum ETHYLENE RESPONSE1 (SlETR1) gene, Sletr1-1 and Sletr1-2, were isolated from the Micro-Tom mutant library by TILLING in our previous study. They displayed different levels of impaired fruit ripening phenotype, suggesting that these alleles could be a valuable breeding material for improving shelf life of tomato fruit. To conduct practical use of the Sletr1 alleles in tomato breeding, genetic complementation analysis by transformation of genes carrying each allele is required. In this study, we generated and characterized transgenic lines over-expressing Sletr1-1 and Sletr1-2. All transgenic lines displayed ethylene insensitive phenotype and ripening inhibition, indicating that Sletr1-1 and Sletr1-2 associate with the ethylene insensitive phenotype. The level of ethylene sensitivity in the seedling was different between Sletr1-1 and Sletr1-2 transgenic lines, whereas no apparent difference was observed in fruit ripening phenotype. These results suggested that it is difficult to fine-tune the extent of ripening by transgenic approach even if the weaker allele (Sletr1-2) was used. Our present and previous studies indicate that the Micro-Tom mutant library combined with TILLING could be an efficient tool for exploring genetic variations of important agronomic traits in tomato breeding.  相似文献   
77.
It is well known that heart rate or arterial blood pressure may increase in response to surgical stimulation despite the absence of a purposeful movement. However, there is limited information regarding anesthetic requirement for blunting adrenergic response in dogs. This study was designed to compare the minimum alveolar concentrations of sevoflurane required to prevent autonomic response (MAC-BAR) and purposeful movement (MAC) in dogs. Sevoflurane MAC-BAR and MAC were determined in 5 beagle dogs by judging dogs' response to a noxious electrical stimulus applied to the gingiva. The sevoflurane MAC-BAR was significantly higher than MAC (3.33 ± 0.48 vs 2.10 ± 0.28%, P=0.005). These results suggested that autonomic responses occurred at sevoflurane anesthetic concentrations at which purposeful movements were absent.  相似文献   
78.
79.
Medical evaluations were performed on free-ranging and captive Matschie's tree kangaroos (Dendrolagus matschiei) in Papua New Guinea. The health assessment included physical examination, morphometrics, cloacal swab; and blood, hair, and feces collection. Radio-collars were placed on free-ranging tree kangaroos to determine home range and forest habitat use. The free-ranging tree kangaroos were lightly anesthetized with tiletamine/zolazepam for the data collection. A total of nine free-ranging and seven captive tree kangaroos were evaluated; medical samples were collected from six and five animals, respectively. Results of physical examination, anesthetic monitoring, serum vitamin, mineral, trace nutrient, and electrolytes, whole blood heavy metal analysis, mycobacterial screening, and fecal examinations are presented. Free-ranging tree kangaroos had significantly lower values for beta carotene, copper, selenium, molybdenum, lead, and arsenic and significantly higher values for vitamin E than captive individuals. Cloacal swabs were all negative for Mycobacterium avium via polymerase chain reaction. Some free-ranging and captive individuals had positive coprologic exams revealing Eimeria spp. oocysts and strongyle spp. type ova. These are the first medical and anesthetic data published on Matschie's tree kangaroos from Papua New Guinea.  相似文献   
80.
Background: Growing interest in veterinary oncohematology has facilitated the recent development and advancement of new techniques, such as flow cytometry, for immunophenotyping hematopoietic neoplasia in animals. Objective: The aim of this retrospective study was to characterize hematologic abnormalities and flow cytometric immunophenotyping (FCI) results in cases of hematopoietic neoplasia in dogs. Methods: Signalment, CBC data, and FCI results were obtained for 210 dogs with blood samples submitted to our laboratory. Immunophenotyping was carried out using an Epics XL‐MCL flow cytometer and a panel of 10 antibodies (CD45, CD3, CD4, CD8, CD79, CD21, CD14, CD34, CD41/61, CD61). The prevalence and severity of hematologic abnormalities was determined for the different types of hematopoietic neoplasms. Results: Based on cell morphology and phenotype, cases were classified as: acute lymphoblastic leukemia (ALL, n=51), acute myeloid leukemia (AML, n=33), chronic lymphocytic leukemia (CLL, n=61), and leukemic high‐grade lymphoma (L‐HGL, n=65). Most cases of ALL (47/51) and L‐HGL (41/65) had a B‐cell phenotype, while most cases of CLL (54/61) had a T‐cell phenotype, with a high prevalence of the large granular lymphocyte subtype (49/61). Anemia was found in 85% of all cases and was significantly more severe in ALL and AML compared with CLL and L‐HGL. Neutropenia was seen in 64–78% of acute leukemias (AML and ALL) in contrast to no cases of CLL and 11% of L‐HGL. Thrombocytopenia was seen in 88–90% of acute leukemias in contrast to 15% of CLL and 40% of L‐HGL. Thrombocytopenia was more prevalent (71% vs 22%) and significantly more severe in T‐cell vs B‐cell L‐HGL. Conclusion: A standard CBC is useful in suggesting the type of hemoproliferative disorder and may also help to predict the phenotype, especially in cases of L‐HGL.  相似文献   
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