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101.
BACKGROUND: Systolic dysfunction associated with chronic mitral valve insufficiency (CMVI) has been demonstrated in experimental animal models and large breed (LB) dogs but has been reported as an uncommon finding in small breed (SB) dogs with naturally occurring disease. It has been suggested the myocardial failure could be, in part, because of an insufficient increase in left ventricular mass. HYPOTHESIS: To test if SB and LB dogs with CMVI and moderate heart failure have systolic dysfunction and if they have adequate eccentric hypertrophy. ANIMALS: Data from 38 SB and 18 LB dogs affected with CMVI were compared retrospectively with results from 2 groups of normal dogs (17 SB and 32 LB). METHODS: Systolic function was investigated echocardiographically by using percentage fractional shortening (FS), the ratio between observed and expected end-systolic diameter (ESD/ESDe), and end-systolic volume index (ESVI). Left ventricular hypertrophy was estimated by using the ratio between the thickness of the left ventricular free wall and the radius in diastole (h/R). RESULTS: Both affected SB and LB dogs had a significantly increased FS and ESVI (FS% SB 45.6 + 8.04 versus 40.06 + 8.9, P < .05; FS% LB 33.64 + 8.61 versus 27.3 + 7.3 P < .05; ESVI SB 30.0 +/- 2.3 mL/m2 versus 21.18 +/- 13.9 mL/m2, P < .05; ESVI LB 83.22 +/- 43.84 mL/m2 versus 36.43 +/- 13.30 mL/m2 versus P < .001). The h/R in affected animals was decreased (0.53 +/- 0.11 versus 0.41 +/- 0.12, P < .05 SB; 0.47 +/- 0.11 versus 0.38 +/- 0.09, P < .05, LB). CONCLUSIONS AND CLINICAL IMPORTANCE: Data from this study indicate that dogs with moderate heart failure caused by CMVI have systolic dysfunction. Inadequate hypertrophy of the left ventricle may be, in part, responsible for this finding.  相似文献   
102.
Background: Metabolic profile was initially designed as a presymptomatic diagnostic aid based on statistical analyses of blood metabolites to provide an early warning of certain types of metabolic disorder. However, there is little metabolic profile data available about Korean Hanwoo cows. Therefore, this study aimed to determine the reference intervals of metabolic profile for Korean Hanwoo cows.Methods: Healthy animals(2,205) were selected and divided into early(day 1 to 95), middle(day 96 to 190) and late(day 191 to 285) period according to their gestating period. Metabolic profile including total protein(TP), albumin(Alb), urea(UREA), glucose(Glu), total cholesterol(T-Cho), long-chain fatty acid(LCFA), aspartate aminotransferase(AST),gamma-glutamyl transpeptidase(GGT), creatinine(Crea), calcium(Ca), inorganic phosphorous(i P) and magnesium(Mg)were analyzed using a TBA-40 FR automatic biochemical analyzer. The data of Korean Hanwoo cows were then compared to those of the Japanese Wagyu cows.Results: Most of the data of the Korean Hanwoo cows were relatively higher than those of Japanese Wagyu cows, with the exception of Glu and GGT. This may indicate that the nutritional level of feed for the Korean Hanwoo cows was higher than that of the Japanese Wagyu cows because of the different feeding system. In particular, relatively higher levels of UREA and LCFA were observed in the Korean Hanwoo cows, and this may also contribute to the low reproduction efficiency.Conclusions: These findings may provide some theoretical basis for understanding the reproductive and feeding situation of Korean Hanwoo cows.  相似文献   
103.
Genetic Resources and Crop Evolution - The development of segregating populations in papaya allows the development of new high fruit yield and excellent fruit quality pure line or hybrid cultivars....  相似文献   
104.
Biogas must be pretreated before its use; thus, both physical and chemical methods have been implemented to remove the fuel’s principal pollutants (CO2 and H2S). Additional removal methods that use microorganisms’ biological processes to eliminate pollutants have also emerged. A selection was made from six bacterial isolates to obtain consortia that removed CO2 and eventually H2S through the enrichment of cultures and the construction of clone libraries of gene 16S ribosomal DNA (rDNA). The results indicate that the principal differences between consortia were determined in the culture medium. C5 and C6 consortia had photosynthetic biomass 1.42 and 1.52 μg/ml, respectively, and concentration of dissolved CO2 100.6 and 99.1 mg/l, respectively. The clone libraries showed that Rhodopseudomonas sp. had percentages 46.6, 42.5, and 86.8 % in C4, C5, and C6, respectively; Xanthobacter sp., 24.5 %, Castellaniella sp., 18 % in C5, and Sphingobium sp., 39.2 % in C4.  相似文献   
105.
Mars' polar regions are covered with ice-rich layered deposits that potentially contain a record of climate variations. The sounding radar SHARAD on the Mars Reconnaissance Orbiter mapped detailed subsurface stratigraphy in the Promethei Lingula region of the south polar plateau, Planum Australe. Radar reflections interpreted as layers are correlated across adjacent orbits and are continuous for up to 150 kilometers along spacecraft orbital tracks. The reflectors are often separated into discrete reflector sequences, and strong echoes are seen as deep as 1 kilometer. In some cases, the sequences are dipping with respect to each other, suggesting an interdepositional period of erosion. In Australe Sulci, layers are exhumed, indicating recent erosion.  相似文献   
106.
The ecological importance of marine algae is widely known but in shallow coastal areas the composition and structure of algal communities may be affected by different human activities. Recovery from different trampling disturbances of two competing morphological groups (i.e. macroalgae and algal turfs) and effects of macroalgal canopy removal on the dominant associated fauna were examined using controlled trampling experiments. Six months after trampling disturbance was removed, the two morphological groups closely resembled control (untrampled) conditions, both in terms of cover and canopy (%). In particular, macroalgal recovery seemed to be very rapid: the higher the impact on the system the more rapid the recovery rate. In the short-term, the removal of macroalgal fronds (i.e. canopy) caused evident changes in invertebrate and crypto-benthic fish densities although these indirect effects were species-specific. Erect macroalgae are very sensitive to disturbance and even relatively low intensities of human use may be non-sustainable for this shallow assemblage. The present findings suggest some interesting options for the management of Mediterranean rocky shallow areas. This is crucial for coastal areas that are intended to be maintained in natural condition for conservation purposes.  相似文献   
107.
In this study of the behavior of coumaric acid added to soil, the disappearance of the acid was found to be due to adsorption plus microbial degradation, and was influenced by the concentration and contact time. Adsorption experiments set up with soils varying widely in their chemical and physical properties, showed that the Freundlich isotherm fits the data quite well and that among the different soil factors, only the pH was closely and negatively correlated with coumaric acid adsorption. Approximately at pH > 7 no adsorption occurred, perhaps due to the repulsion between the negatively charged soil colloids and the dissociated acidic groups of coumaric acid. Adsorption experiments carried out with different adsorbents showed that the hydroxy-Fe compound was the most effective in retaining coumaric acid, followed by humic acid, illite, kaolinite and vermiculite, in this order.  相似文献   
108.
A nutritional study ofDioclea grandiflora (Mucuna) andDioclea sclerocarpa, two legume seeds related toCanavalia which grow extensively in South America and are used as a human food source, has been carried out. Whilst both seeds, when fed to rats at a level equivalent to 100g seed protein kg–1 diet gave poor nutritional performance, the anti-nutritional factors involved were apparently different. WithDioclea grandiflora, the presence in the seed of a soluble small molecular weight component, which caused food intake to be reduced to levels well below that required to meet minimum protein, energy, vitamin and mineral requirements, led to poor growth. This factor could be reduced substantially by exhaustive dialysis or by aqueous ethanol extraction of the meal. These procedures may have potential practical applications. In addition, the constitutent lectin, which was partially resistant in vitro and in vivo to degradation by gastrointestinal enzymes, also contributed to growth depression. WithDioclea sclerocarpa, a non-haemagglutinating pH 7 soluble factor was primarily responsible for the poor performance of rats. This factor could not be removed by exhaustive dialysis. The apparently poor protein digestibility observed may be due to increased secretion of endogenous nitrogen.  相似文献   
109.
Sustainable remediation comprises soil and groundwater risk-management actions that are selected, designed, and operated to maximize net environmental, social, and economic benefit (while assuring protection of human health and safety). This paper describes a benchmarking exercise to comparatively assess potential differences in environmental management decision making resulting from application of different sustainability appraisal tools ranging from simple (qualitative) to more quantitative (multi-criteria and fully monetized cost-benefit analysis), as outlined in the SuRF-UK framework. The appraisal tools were used to rank remedial options for risk management of a subsurface petroleum release that occurred at a petrol filling station in central England. The remediation options were benchmarked using a consistent set of soil and groundwater data for each tier of sustainability appraisal. The ranking of remedial options was very similar in all three tiers, and an environmental management decision to select the most sustainable options at tier 1 would have been the same decision at tiers 2 and 3. The exercise showed that, for relatively simple remediation projects, a simple sustainability appraisal led to the same remediation option selection as more complex appraisal, and can be used to reliably inform environmental management decisions on other relatively simple land contamination projects.  相似文献   
110.
Several approaches are available to achieve multi-transgene-stacking in plants for the introduction of complex or multiple traits. We used co-transformation with multiple plasmids using particle bombardment and hybridization of plants carrying separate transgenes in wheat. In the co-transformation approach, four constructs containing the defence genes Pvpgip2, Acpmei, Taxi-III or Xip-III and the bar gene were co-bombarded into immature embryos of durum or common wheat. The four transgenes integrated into the wheat genome at co-transformation frequencies of 58 and 27 % in durum and common wheat, respectively. Segregation analysis of the T1 and T2 generations showed that 45–90 % of the progeny inherited all four transgenes together in both durum and common wheat. In the hybridization approach, pyramiding of Pvpgip2, Acpmei and Taxi-III was achieved by crossing durum wheat plants containing the Pvpgip2 and Acpmei transgenes with transgenic plants carrying Taxi-III. Segregation analysis showed that only 4.5 % of the progeny inherited all four transgenes together, including the bar gene. Co-expression analyses of Pvpgip2, Acpmei and Taxi-III or Xip-III showed loss of mRNA or protein activity in the progenies of both transgenic and hybrid wheat lines. Particle bombardment yielded progenies with either tightly linked transgenes or with different transgene combinations that could be useful in research applications. However, its efficiency was constrained by the occurrence of transgene silencing.  相似文献   
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