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51.
52.
Food quality aspects of farmed turbot (Psetta maxima) were compared following two methods of slaughter: the current commercial method, by immersion in an ice slurry, which is then dewatered after approximately 20 min, or by first humanely, electrically stunning the fish using a prototype commercial stunner, before immersion in an ice slurry, which is dewatered after 20 min. Quality was assessed for up to 10 days of storage on ice following slaughter. No differences were found between the slaughter methods in terms of an overall carcass quality: overall appearance, haemorrhage, damage, burst gall bladder, staining of the body cavity by leakage from the gut or damage to the spine. No detectable difference was found between the treatments using the industry standard freshness scoring system, the Quality Index Method. Both groups of fish were classified as ‘Fresh’ after 10 days of storage on ice. Using objective measurements of colour, no differences between fish from either treatment were found in fillet colour. Changes in flesh pH were similar in electrically stunned and traditionally killed fish with a mean pH (±SE) at 2 h post‐mortem of 6.80±0.027 declining to 6.44±0.032 at 24 h post‐mortem. Humane electrical stunning of turbot at slaughter neither detectably improved nor decreased product quality as measured between 1 and 10 days of storage on ice.  相似文献   
53.
OBJECTIVE: To determine whether atropine altered the degree of mucosal eversion during jejunal resection and anastomosis in the dog. STUDY DESIGN: Part I: Prospective, blinded, randomized, controlled study using a therapeutic dose (0.04 mg/kg systemic) of atropine. Part II: Prospective, unblinded, assigned, controlled study using a pharmacologic (0.04 mg/kg local arterial) dose of atropine. ANIMALS: Part I: Twenty-two young adult female Beagle dogs used during a nonsurvival third-year veterinary student surgical laboratory (small intestinal resection and anastomosis). Part II: Ten young adult female Beagle dogs used immediately after completion of a nonsurvival third-year veterinary student orthopedic surgical laboratory. METHODS: Part I: Dogs were randomly assigned to receive either atropine (0.04 mg/kg), or an equal volume of saline, given intramuscularly (premedication) and again intravenously prior to intestinal resection. Part II: In each dog, atropine (0.04 mg/kg)/saline was alternately given in the proximal/distal jejunum. RESULTS: Part I: There was no clinically or statistically significant difference between systemic atropine and saline solution on the degree of jejunal mucosal eversion after resection. Part II: There was a statistically significant decrease in jejunal mucosal eversion with atropine compared with saline solution when injected into a local jejunal artery. CONCLUSION: Systemic atropine (0.04 mg/kg) does not alter the degree of jejunal mucosal eversion during resection and anastomosis. Jejunal intraarterial atropine (0.04 mg/kg) reduced jejunal mucosal eversion during resection and anastomosis. CLINICAL RELEVANCE: The clinical usefulness and consequences of jejunal arterial atropine administration to reduce mucosal eversion remain to be determined.  相似文献   
54.
The ability of a Japanese quail fibrosarcoma cell line (QT-35) to support the replication of avian metapneumoviruses belonging to the 3 subgroups A (14/1 virus), B (Colorado virus), and C (Hungary virus) enabled the development of assays for the detection and evaluation of virus-specific antibodies. On the basis of the results of enzyme-linked immunosorbent assay (ELISA), plaque reduction neutralization assay (PRNA), immunofluorescent assay (IFA), and Western blot analysis, some degree of antigenic cross-reactivity was observed between prototype viruses belonging to each of the 3 subgroups A, B, and C. The antigen produced in QT-35 cells was found to be superior with respect to its reactivity with virus-specific antibodies, as determined when used in ELISA and IFA. Standardization of both the input virus and the virus-specific antibodies in PRNA enabled a more detailed analysis of the antigenic relationship between these viruses. Specifically, it was observed that 14/1 virus shared more neutralizing regions with Hungary and Colorado viruses than did either of these viruses with 14/1 virus. In addition, Hungary virus shared comparatively fewer neutralizing epitopes with the Colorado virus than did 14/1 virus. Western blot analysis of the reactivity patterns of virus antigen, produced in QT-35 cells, with subgroup-specific antibodies identified a cross-reactive protein migrating at approximately 18 kD. These assays and the information from the Western blot will enable further analysis of avian metapneumovirus isolates to determine antigenic relationships.  相似文献   
55.
The 541 × Ot1-3 intercross population and bulked segregant analysis (BSA) were used to search for molecular markers linked to genes underlying sprouting and alpha-amylase activity. Six RAPD markers showing association with studied traits were tested for their potential effectiveness in selecting sprouting resistant genotypes. It was shown that although individual effects of markers were not high, their accumulation in one genotype gives substantial increase in sprouting resistance.  相似文献   
56.
There were two objectives in the study: 1) To determine exchangeable K and non-exchangeable K in soils with different potassium depletion levels and mineralogy as plant sources 2) To establish a relationship between the mineralogy vs exchangeable K (Ke) and non-exchangeable K (Kne) mobilization. An extraction experiment of soils was carried out in a greenhouse, with a total of 6 consecutive crops of ryegrass. Different supply rates for plant K were determined by Ke and Kne mobilization according to the soil intensity of use. The contribution of the Ke was greater and generated higher amount of K uptake during maximum availability period (from 0 to the 1st harvest) than in the later period when soil K was already depleted. For this the initial exchangeable K and the illite concentration of soils accounted for almost 100% (R2 = 0.981 P=0.01) of the K taken up by ryegrass. For the following period (from the 2nd harvest to the 6th), Kne forms became more important. Plant K supply was not only a result of initial exchangeable K and illite concentration but presumably also of primary K-bearing minerals.  相似文献   
57.
Dominga grape polyphenol oxidase (PPO) was extracted using phase partitioning with Triton X-114. The enzyme was obtained in latent state and could be optimally activated by the presence of 0.2% sodium dodecyl sulfate (SDS) at pH 6.0. In the absence of SDS, the enzyme showed maximum activity at acid pH. The kinetic parameters of the enzyme at pH 3.0 and 6.0 in the presence of SDS were calculated. The effect of several inhibitors was studied, tropolone being the most effective with a K(i) value of 18 muM. The effect of cyclodextrins was also studied, and the complexation constant K(c) between G(2)-beta-cyclodextrins and 4-tert-butylcatechol was calculated using the enzymatic method (K(c) = 13960 M(-)(1)). The evolution of the color parameters (L, a, b) of liquefied grape berries was inhibited by inhibitors of PPO activity, such as diethyldithiocarbamate, metabisulfite, and G(2)-beta-cyclodextrins, indicating that enzymatic browning by PPO is the main process involved in the browning of Dominga grape juice at room temperature.  相似文献   
58.
Supercritical fluid extraction of all-trans-lycopene from tomato   总被引:6,自引:0,他引:6  
A procedure is proposed for the supercritical fluid extraction of all-trans-lycopene from tomato using carbon dioxide at 40 degrees C without modifier. The present method minimizes the risk of degradation via isomerization and oxidation of health-promoting ingredients, such as lycopene. The effect of different experimental variables on the solvating power of the supercritical fluid was evaluated in terms of both the selectivity achievable in the process and the yield of the extraction of all-trans-lycopene. Satisfactory separations of the all-trans-lycopene isomers from the cis counterparts were achieved using a C(30) column. The obtained extract contained 88% all-trans-lycopene and 12% cis-lycopene.  相似文献   
59.
棉苗营养钵移栽打穴机系多杆组合机构,通过优化设计,在主体的曲柄摇杆机构的连杆上,正确地确定了安装打穴筒的方位,且在摇杆与动点M_1之间联接一个空间机构,使打穴筒在切土工作行程同时,绕自身轴线转动,以利切土。通过电视屏幕与模型调试,使打穴筒在近穴底反转,以利断土。通过技术鉴定的机型在生产中较受棉农欢迎。  相似文献   
60.
Through the ethnographic record of the subsistence activities partially or completely performed in the domestic sphere in two Mbyá-Guaraní settlements in Misiones (Argentina), we outline factors important in describing the local natural environment. Data was collected through systematic observation and also through semi-structured interviews. Analysis indicates that the natural environment of the area is characterized by the indigenous community in several different ways. Thus, local people view the environment as made up of different “micro-environments,” and they consequently think of the elements that compose these “micro-environments” as having different, distinct characteristics. In the context of their daily activities, both these “micro-environments” and the elements that compose them are regarded as resources, in that they are viewed in terms of what is in them relevant to the subsistence of these groups in the rainforest. It is the intention of this study to initiate the systematic recording and processing of information on how these indigenous communities know and manage the natural resources available to them in their daily life.  相似文献   
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