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61.
Carotenoids from Marine Microalgae: A Valuable Natural Source for the Prevention of Chronic Diseases
Maria Filomena de Jesus Raposo Alcina Maria Miranda Bernardo de Morais Rui Manuel Santos Costa de Morais 《Marine drugs》2015,13(8):5128-5155
Epidemiological studies have shown a relation between antioxidants and the prevention of several chronic diseases. Microalgae are a potential novel source of bioactive molecules, including a wide range of different carotenoids that can be used as nutraceuticals, food supplements and novel food products. The objective of this review is (i) to update the research that has been carried out on the most known carotenoids produced by marine microalgae, including reporting on their high potentialities to produce other less known important compounds; (ii) to compile the work that has been done in order to establish some relationship between carotenoids and oxidative protection and treatment; (iii) to summarize the association of oxidative stress and the various reactive species including free radicals with several human diseases; and (iv) to provide evidence of the potential of carotenoids from marine microalgae to be used as therapeutics to treat or prevent these oxidative stress-related diseases. 相似文献
62.
Guimes Rodrigues Filho Sabrina Dias RibeiroCarla da Silva Meireles Leandro Gustavo da SilvaReinaldo Ruggiero Moacir Fernandes Ferreira JuniorDaniel Alves Cerqueira Rosana Maria Nascimento de AssunçãoMara Zeni Patricia Polleto 《Industrial Crops and Products》2011,33(3):566-571
Cellulose acetate is one of the components employed in drug controlled-release systems in the form of membranes. The aim of this study was to examine the controlled-release of doxycycline employing cellulose acetate symmetric and asymmetric membranes as matrices. The cellulose triacetate was produced from sugarcane bagasse through a homogeneous acetylation reaction, using acetic acid as the solvent, acetic anhydride as the acetylating agent and sulfuric acid as the catalyst. The viscosity average molecular weight of the cellulose acetate produced was 39,000 g mol−1. The symmetric membranes were produced using a system solvent of dichloromethane/ethanol (9:1, v/v) and the asymmetric membranes were produced from the same solvent system and 10% of water. For the formulation of both, 5% of doxycycline was used. The membranes were characterized by thermal analysis (DSC and TGA) and scanning electron microscopy SEM. The release of doxycycline through cellulose triacetate matrices was examined using spectrophotometric analysis in the ultraviolet-visible region, at 275 nm. The results revealed that asymmetric membranes release 80% of the drug in 100 min, while symmetric membranes release 14% of the drug during the same time interval. 相似文献
63.
Maria Laura Brignoli Paolo Espa Ramon J. Batalla 《Journal of Soils and Sediments》2017,17(8):2187-2201
Purpose
Sediment transport and riverbed sedimentation were investigated in an alpine stream below a small hydropower reservoir desilted by a controlled sediment flushing (CSF) operation. The term “controlled” refers to the operational tasks implemented to mitigate the downstream environmental impact of the operation. The experimental dataset acquired before, during, and after the CSF was also used to carry out and calibrate a one-dimensional sediment transport model of the monitored event.Materials and methods
The investigated reservoir is located in the central Italian Alps, and its original storage was 160,000 m3, about 30% filled by a mixture of sand and silt/clay before the CSF. Downstream sediment concentration was controlled by releasing clear water from upstream reservoirs and regulating the work of earth-moving equipment in the emptied reservoir. A 3.6-km-long reach with average slope of 0.015 was monitored: concentration and grain size of suspended sediment were measured during the CSF and the riverbed alteration was evaluated by volumetric sampling and measurements of the deposits’ thickness. Sedimentation and River Hydraulics—One Dimensional (SRH-1D) was used to simulate sediment transport during the monitored CSF. Model parameters were calibrated by comparing the computed and the observed amount of sediment deposited along the study reach.Results and discussion
Sediment flushing was carried out in October 2010 for 3 days. Ca. 16,000 m3 of sediment were evacuated, representing approximately 30% silt/clay and 70% sand. 2.4 Mm3 of clear water was released to reduce sediment concentration and increase transport capacity downstream. About 3000 m3 of sand was deposited in the study reach after the CSF, with maximum height up to 0.2 m. Although the riverbed before the CSF was simply set as mono-granular, after calibrating the parameters, good agreement was achieved between the depositional pattern computed by SRH-1D and the one observed, both in terms of deposit thickness and grain size of deposited sediment. The sensitivity analysis revealed a major role of the parameters controlling bed mixing processes in affecting the simulated deposition after the CSF.Conclusions
Sediment below 0.1 mm in diameter was not detected in river deposits after the flushing: the effects on river biota associated with substrate clogging by very fine sediment were therefore minimized. After proper calibration, 1-D sediment transport modeling can effectively support the planning of CSF operations: to minimize the downstream environmental effects, concurrently achieving acceptable flushing efficiency, the analyzed scenarios as well as the model outputs need to be carefully evaluated from a multidisciplinary perspective.64.
Yvonne Sadovy George Mitcheson Maria B. Rasotto 《Aquarium Sciences and Conservation》2001,3(4):253-263
The mandarinfish, Synchiropus splendidus, is a small, pelagic-spawning enthic dragonet of the western Pacific. Although popular in the marine aquarium trade, little
is known of its fishery or biology. All aquarium-trade animals are currently taken from the wild and the impact of heavy collecting
is unknown. The specialized and selective nature of the fishery for mandarinfish is described and its potential to disrupt
the mating system identified. As a possible alternative to wild capture and as an aid to sustainable exploitation, egg production
and early development relevant to mariculture are described, including egg output, embryo, larva and post-settlement development
to 30 days, based on live material. Egg output was determined for 40 females and ranged from 12 to 205 eggs. Embryo and larva
development were rapid, with settlement occurring within 14 days at 24–26 °C, and at 3.5 mm TL. The swimbladder is retained
in adults. Our limited attempts at raising the mandarinfish to settlement were encouraging and suggest an excellent potential
for mariculture with implications for both conservation and improved maintenance of fish in captivity. At present, given that
this species is difficult to maintain in captivity, it is only suitable for experienced aquarists. Preliminary diet information
is provided.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
65.
Maria Margarida Ribeiro Leopoldo Sanchez Carla Ribeiro Fátima Cunha José Araújo Nuno M. G. Borralho Cristina Marques 《Annals of Forest Science》2011,68(4):701-714
• Introduction
Tree genetic improvement programs usually lack, in general, pedigree information. Since molecular markers can be used to estimate the level of genetic similarity between individuals, we genotyped a sample of a Portuguese Eucalyptus globulus breeding population—a reference population of 125 individuals—with 16 microsatellites (SSR). 相似文献66.
Rotacio S. Gravoso Nestor O. Gregorio Maria Anabelle D. Gerona Moises Neil V. Seri?o Steve R. Harrison Herville V. Pajaron Jayson V. Godoy 《Small-Scale Forestry》2011,10(4):473-488
Through a series of workshops with the stakeholders including nursery operators, tree farmers, staff of the Department of
Environment and Natural Resources, local government units and the academe, a forestry seedling nursery accreditation policy
was developed. The resulting policy was subsequently implemented by the municipal government of Palompon, Leyte. The accreditation
policy encouraged nursery operators to follow smallholder-based best management practices for tree nurseries. Implementation
of the nursery accreditation policy improved farmers’ knowledge and skills in the production of high quality seedlings, encouraged
adoption of BMP for forest nurseries, provided additional source of income for the farmers, enabled members of the groups
operating the communal nursery to forge closer relationship with each other, encouraged utilization of farmers’ free time
in productive activities, developed farmers’ confidence in producing high quality planting materials, and gained for the farmers
favourable attention from various organizations and groups. The Bennett’s hierarchy of project outcomes showed that the implementation
of accreditation scheme achieved high levels of outcomes, indicating that it led to substantial improvements in the lives
of the farmers. 相似文献
67.
In spite of interest in the cultivation of the pejerrey fish Odontesthes bonariensis (Cuvier & Valenciennes 1835), there are few studies on subjects required to advance this activity. One of the problems is the synchronization of female and male maturation to provide eggs and sperm for larval production. The low volume of expressible milt, either in wild or culture fish, is a major problem. The aim of this work was to study the effectiveness of the administration of different hormones on sperm production in pejerrey. Milt production was enhanced by the injection of human chorionic gonadotropin (hCG) (16.7‐fold increase, 625 IU kg?1), carp pituitary extracts (13.5‐fold increase, 30 mg kg?1), salmon pituitary extracts (12.8‐fold increase, 30 mg kg?1), salmon‐type gonadotropin‐releasing hormone analogue (GnRH) (16.7‐fold increase, 10 μg kg?1) and mammalian‐type GnRH analogue (10.8‐fold increase, 20 μg kg?1). Sperm concentration, motility and the fertilization rate were not statistically different compared with control groups. It was also demonstrated that sperm could be obtained off‐season. Taken together, hCG is recommended to stimulate pejerrey spermiation because it is effective in low doses is inexpensive and is widely available. 相似文献
68.
Soil chemical and biochemical properties of a salt-marsh alluvial Spanish area after long-term reclamation 总被引:2,自引:0,他引:2
Vito Armando Laudicina Maria Dolores Hurtado Luigi Badalucco Antonio Delgado Eristanna Palazzolo Michele Panno 《Biology and Fertility of Soils》2009,45(7):691-700
Marisma, one of the largest salt-marsh alluvial areas in SW Spain, has been reclaimed since 1970 by artificial drainage and
amendment with phosphogypsum (PG) so as to reduce Na+ saturation. Within the reclaimed area, two 250- × 20-m plots were treated as follows: (1) amendment with 25 Mg/ha of PG every
2 to 3 years between 1979 and 2003 (plot PY); (2) like PY but PG treatment stopped after 1997 (plot DR). A contiguous virgin
Marisma salt-marsh plot (MV), neither drained nor amended, was the control. In MV, soil microbial biomass C, most enzyme activities
and total organic C content were much greater than in PY and DR soils, despite the salinity stress. The decrease in soil organic
matter content in PY and DR soils was likely due to cotton-cropping practices, which favoured the organic C mineralisation
and nutrients removal by crops. Microbial activity of MV soil, probably stimulated by the rhizodepositions of the natural
vegetation, did not suffer from the osmotic effect due to the raising of soil solution ionic strength. Microbial quotient
could be ranked as MV > PY > DR, whereas the metabolic quotient had an opposite trend. Thus, both quotients suggested that
the interruption of PG amendment was not favouring microbial activity. Principal component analysis clearly identified the
chemical and biochemical soil properties mostly affected by the reclamation and also indicated the longer PG amendment in
PY plot. Stepwise discriminant analysis identified two physiologically different types of soil microflora, one less active
present in the MV virgin soil and another more active present in the reclaimed PY and DR soils. 相似文献
69.
Giovanni Romagnoni Kristina
ie Kvile Knut‐Frode Dagestad Anne Maria Eikeset Trond Kristiansen Nils Chr. Stenseth
ystein Langangen 《Fisheries Oceanography》2020,29(4):324-339
The survival of fish eggs and larvae, and therefore recruitment success, can be critically affected by transport in ocean currents. Combining a model of early‐life stage dispersal with statistical stock–recruitment models, we investigated the role of larval transport for recruitment variability across spatial scales for the population complex of North Sea cod (Gadus morhua). By using a coupled physical–biological model, we estimated the egg and larval transport over a 44‐year period. The oceanographic component of the model, capable of capturing the interannual variability of temperature and ocean current patterns, was coupled to the biological component, an individual‐based model (IBM) that simulated the cod eggs and larvae development and mortality. This study proposes a novel method to account for larval transport and success in stock–recruitment models: weighting the spawning stock biomass by retention rate and, in the case of multiple populations, their connectivity. Our method provides an estimate of the stock biomass contributing to recruitment and the effect of larval transport on recruitment variability. Our results indicate an effect, albeit small, in some populations at the local level. Including transport anomaly as an environmental covariate in traditional stock–recruitment models in turn captures recruitment variability at larger scales. Our study aims to quantify the role of larval transport for recruitment across spatial scales, and disentangle the roles of temperature and larval transport on effective connectivity between populations, thus informing about the potential impacts of climate change on the cod population structure in the North Sea. 相似文献
70.
Snjeana Pe
ur Kazazi Natalija Topi Popovi Ivan
ica Strunjak‐Perovi Daniela Florio Maria Fioravanti Sanja Babi Rozelindra o‐Rakovac 《Journal of fish diseases》2019,42(8):1201-1209
MALDI‐TOF MS was tested for the identification of Photobacterium damselae subsp. piscicida on isolates grown on two media, cultured at three incubation times and applied on the target plate by the direct sample spotting (DS), by the on‐target extraction (OTE) and by the full extraction (FE) method, in triplicates. The identification of samples grown on blood agar (BA) outperformed identification on tryptic soya agar (TSA) by 0.64% for DS and OTE. The OTE gave the highest scores in both culture media, all incubation times and replicates. Reliable 24‐hr species identification was 61.54%, 84.61% and 53.85% for samples grown on TSA and identified by DS, OTE and FE, respectively. For isolates grown on BA, they were 76.92%, 96.15% and 30.77%, respectively. When identified by OTE, the 48‐hr identification was 93.58%, but for 72 hr declined to 71.79%. The reliable identification with the highest score from the first measurement was 100% only for OTE from BA (24 hr), whereas OTE from TSA gave 84.61% (24 hr), 76.92% (48 hr) and 84.61% (72 hr). The reliable MALDI‐TOF MS identification of Ph. damselae subsp. piscicida is incubation time, media, target plate preparation and replicate‐dependent. 相似文献