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341.
Four varieties of common bean were examined, but there were no significant differences among them. Crude protein content (46.7% and 49.0%) was the main constituent in embryonic axes. The average values of ash, crude fiber and ether extract were 4.2%, 3.7% and 3.0% respectively. Starch was approximately three times more abundant (7.5%) than cellulose (2.7%). Hemicellulose B values were lower (5.5%) than hemicellulose A (9.2%). The mean value of the pectic substances in embryonic axes was 12.3%. The free ethanol-soluble sugars ranged from 2.9% to 4.9%. Verbascose, stachyose, raffinose, sucrose, and galactose were identified and quantified in embryonic axes. Seed coat flour contained cellulose (30.6%), ether extract (0.4%), ash (2.8%), and protein (5.4%). Free ribose, mannose, arabinose, and galactose were present in seed coats in amounts ranging from 0.009% to 0.031%.  相似文献   
342.
The electrophoretic pattern of the untreated common bean globulin cv. Flor de Mayo had 7 protein fractions ranging from 620 to 120 kilodaltons (kd). The last molecular weight corresponds to the monomeric form. One of the objectives of the present work was to establish a comparison among denaturation by heat, sodium dodecyl sulphate (SDS) and dithiothreitol (DTT). At pH 6.0, two bands were resistant to heat treatment, after SDS treatment of the untreated globulin several bands disappeared and two new bands with 26 and 15 kd appeared. DTT did not change the electrophoretic pattern, due to the small quantity of free SH groups in the globulin. At pH 6.0, phaseolin is partly resistant to heat denaturation due to aggregation in an acidic environment. Isoelectrofocusing (IEF) and SDS polyacrylamide gel electrophoresis (SDS-PAGE) separated phaseolin into 10 protein fractions. The hypothesis is that phaseolin or globulin aggregation is due to the charge difference of fractions.  相似文献   
343.
Pink Lady apples were harvested at commercial maturity and stored at 1 degrees C and 92% relative humidity under either air or controlled atmosphere conditions (2 kPa O 2:2 kPa CO 2 and 1 kPa O 2:1 kPa CO 2) for 27 weeks. Data on the emission of volatile compounds and on the activity of some related enzymes in both skin and flesh tissues were obtained during subsequent shelf life at 20 degrees C. Major effects of storage atmosphere and poststorage period were observed on the emission of volatile esters and their precursors. Changes in the production of volatile esters were partly due to alterations in the activity of alcohol o-acyltransferase, but the specific esters emitted by fruit after storage also resulted largely from modifications in the supply of the corresponding substrates. Samples stored under air were characterized by higher availability of acetaldehyde, whereas those stored under CA showed enhanced emission of the alcohol precursors ethanol and 1-hexanol (2 kPa O 2) and 1-butanol (1 kPa O 2), with accordingly higher production of ethyl, hexyl, and butyl esters. Multivariate analysis revealed that a large part of the observed differences in precursor availability arose from modifications in the activity of the enzymes considered. Higher pyruvate decarboxylase activity in air-stored fruit possibly accounted for higher acetaldehyde levels in these samples, while storage under 1 kPa O 2 led to significantly decreased lipoxygenase activity and thus to lessened production of 1-hexanol and hexyl esters. Low acetaldehyde availability together with enhanced hydroperoxide lyase and alcohol dehydrogenase levels in these fruits are suggested to have led to higher emission of 1-butanol and butyl esters.  相似文献   
344.
The aim of this work was to assess whether extra time spent under AIR conditions after storage in an ultra low oxygen (ULO) atmosphere could allow the regeneration of volatile compound emission without negatively affecting quality parameters and the consumer acceptability of Fuji apples. Fruits were stored for 19 and 30 weeks at 1 degrees C and 92% RH under ULO atmosphere conditions (1 kPa O 2:1 kPa CO 2) or under ULO conditions followed by different periods (2 and 4 weeks) in cold AIR atmosphere (ULO + 2w or ULO + 4w, respectively). Standard quality and emission of volatile compounds were analyzed after storage plus 1 and 7 days at 20 degrees C. Sensory attributes and acceptability were also determined after 7 days at 20 degrees C. The extra period of 30 weeks in an AIR atmosphere after ULO storage resulted in an increase in the concentration of the compounds that most contribute to the flavor of Fuji apples. These fruits were relatively well accepted by consumers despite a slight decline in firmness and acidity.  相似文献   
345.
The evolution of volatile compounds extracted from wood while being macerated for 1 month with four different commercial chips (different geographical origins and toasting degrees) was studied. Furthermore, the effect of the microoxygenation process between alcoholic and malolactic fermentation also was studied. The wood volatile compounds in wines macerated with the four types of chips evolved in the same way. However, the amounts of compounds extracted depended on the type of chip used. There were differences in the levels of vanillin, cis-whiskey lactone, furfural, trans-isoeugenol, and cis-isoeugenol in wines in accordance with the type of wood chips (French or American), and the last two compounds along with 5-methyl furfural presented differences that were directly related to the toast level. However, no effects of microoxygenation treatment on the extraction of volatile compounds extracted from chips were observed. Therefore, the results obtained in this study highlight the importance of chip selection on the aromatic characteristics of finished wines.  相似文献   
346.
OBJECTIVE: To study risk factors for overweight among Brazilian adolescents of low-income families. DESIGN: Case-control study of obese and non-obese adolescents. SETTING: Anthropometric survey including 1420 students (aged 14-19 years) attending a public high school in S?o Paulo, Brazil. METHODS: Selection of 83 overweight (body mass index (BMI) >85th percentile) and 89 non-overweight (BMI >5th percentile and <85th percentile) subjects, frequency-matched by age, gender, pubertal development and socio-economic status. Among the nutritional, familial and behavioural data available, five covariates (parents' obesity, adolescents' past obesity, to have a best friend, dietary restriction and habit of napping) were included in the fitted hierarchical conditional logistic regression models. MEASUREMENTS: Parents or guardians and adolescents were weighed, measured and answered a pre-tested questionnaire applied by trained nutritionists and paediatricians. RESULTS: The prevalence of overweight was 15.2%. As previous risks, obese parents and obesity during infancy presented odds ratios (OR) and 95% confidence intervals (CI) of 2.23 (1.15-4.35) and 3.60 (1.47-8.80), respectively. As concurrent factors, the habit of napping, to have a best friend and reported dietary restriction presented OR (95% CI) of 3.43 (1.32-8.92), 5.15 (1.76-15.07) and 7.26 (2.95-17.88), respectively. Dietary patterns, frequency of obesogenic foods and other physical activity indicators presented no statistical significance. CONCLUSION: In case-control studies, OR may overestimate the true risks. Parents' obesity and previous childhood obesity were identified as risk factors; therefore these factors should be the target for preventive programmes and policies in order to prevent the burden of obesity in the near future.  相似文献   
347.

Purpose

Quarrying activities in areas with serpentinized rocks may have a negative impact on plant growth. Quarry soils generally offer hostile environments for plant growth due to their low-nutrient availability, low organic matter, and high-trace metal content.

Materials and methods

In order to determine the factors that can limit plant revegetation, this study was carried out in two serpentine quarries in Galicia (NW Spain): one abandoned in 1999 and the other still active.

Results and discussion

The results show that in soils developed in the abandoned quarry, the limitations for revegetation were: moderate alkaline pH (7.87–8.05), strong Ca/Mg (<1) imbalance, low N (<0.42 mg kg?1) and P (<2 mg kg?1) content, and high total heavy-metal content (Co 76–147 mg kg?1; Cr 1370–2600 mg kg?1; and Ni 1340–2040 mg kg?1). The limitations were much less intense in the soils developed in the substratum in the active quarry, which were incipient soils poorly developed and permanently affected by the quarrying activity.

Conclusions

Restoration work should be geared toward establishing a stable diverse vegetation cover, including serpentinophile species, which would provide the necessary modifications to correct nutritive imbalances and improve soil quality.
  相似文献   
348.
Journal of Soils and Sediments - This study assessed soils from 36 parks and gardens (Vigo City, NW of Spain) where there are different degrees of traffic intensity and activity. The soils were...  相似文献   
349.
Background: The Globicatella genus comprises Gram-positive, facultative anaerobic, α-hemolytic and catalase negative cocci morphologically and phenotypically very similar to Streptococcus and Aerococcus genus which can lead to misidentification and underestimation of this pathogen. Globicatella species have already been isolated from human and animals with heart and brain disorders. Their clinical relevance in animals, and its zoonotic potential, remains unknown due to the difficulty in their identification.

Objective: To present the isolation, phenotypic and molecular characterization of G. sulfidifaciens from urinary tract infection in sows.

Materials and Methods: Urine samples from 140 sows of two swine herds located in São Paulo State (Brazil) yielded the isolation of three presumptive G. sulfidifaciens strains. Identification and species confirmation were done by MALDI-TOF MS and 16S rRNA sequencing. Strains were further characterized by single enzyme amplified fragments length polymorphism (SE-AFLP) and broth microdilution techniques.

Results: All three isolates were confirmed as G. sulfidifaciens. The SE-AFLP genotyping resulted in distinct fingerprint patterns for each strain. All isolates presented high MIC values to tetracycline, sulphonamides, aminoglycosides and tylosin tartrate, which present high usage in human and animal medicine.

Conclusions: Globicatella sulfidifaciens could be related to sporadic urinary tract infections in swine and appear to present alarming antimicrobial susceptibility profile. It is necessary to differentiate Streptococcus-like microorganisms in routine laboratory diagnostics for the correct identification of underestimated species potentially pathogenic to animals.  相似文献   

350.
Posidonia oceanica (L.) Delile is an endemic Mediterranean marine plant of extreme ecological importance. Previous in vitro and in vivo studies have demonstrated the potential antidiabetic properties of P. oceanica leaf extract. Intestinal glucose transporters play a key role in glucose homeostasis and represent novel targets for the management of diabetes. In this study, the ability of a hydroalcoholic P. oceanica leaf extract (POE) to modulate intestinal glucose transporters was investigated using Caco-2 cells as a model of an intestinal barrier. The incubation of cells with POE significantly decreased glucose uptake by decreasing the GLUT2 glucose transporter levels. Moreover, POE had a positive effect on the barrier integrity by increasing the Zonulin-1 levels. A protective effect exerted by POE against oxidative stress induced by chronic exposure to high glucose concentrations or tert-butyl hydroperoxide was also demonstrated. This study highlights for the first time the effect of POE on glucose transport, intestinal barrier integrity, and its protective antioxidant effect in Caco-2 cells. These findings suggest that the P. oceanica phytocomplex may have a positive impact by preventing the intestinal cell dysfunction involved in the development of inflammation-related disease associated with oxidative stress.  相似文献   
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