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121.
OBJECTIVE: To identify factors associated with sudden early recovery (SER) from anaesthesia in badgers (Meles meles). STUDY DESIGN: Experimental trial. ANIMALS: Ninety-three adult wild badgers. METHODS: Animals were randomly assigned to receive one of four anaesthetics based on medetomidine (M) ketamine (K) and butorphanol (B) combined in different ratios: (i) MKB 20:40:80 microg kg(-1); (ii) MKB 20:40:60 microg kg(-1); (iii) MKB 20:60:40 microg kg(-1); and (iv) ketamine alone 0.2 mg kg(-1). For each animal, induction time was measured and physiological variables (heart rate, respiratory rate and rectal temperature) were recorded at 5-minute intervals during anaesthesia. Cases of SER were recorded and binary logistic regression applied to identify predictive factors. RESULTS: Fourteen animals (15%) exhibited SER. Rectal temperature was the only variable that was a significant predictor of SER. Animals showing SER had significantly higher rectal temperatures which, in contrast to other cases, did not fall during the first 10 minutes of anaesthesia, which was when most SERs occurred. CONCLUSION AND CLINICAL RELEVANCE: We recommend that (i) rectal temperature is closely monitored during wild badger anaesthesia and (ii) that animals with higher than expected temperatures are treated with additional caution.  相似文献   
122.
Chloroplast microsatellites (SSRs) are conserved within wheat species, yet are sufficiently polymorphic between and within species to be useful for evolutionary studies. This study describes the relationships among a very large set of accessions of Triticum urartu Thum. ex Gandil., T. dicoccoides (Körn. ex Asch. et Graebn.) Schweinf., T. dicoccon Schrank, T. durum Desf., T. spelta L., and T. aestivum L. s. str. based on their cpSSR genotypes. By characterising the chloroplast diversity in each wheat species in the evolutionary series, the impact on diversity of major evolutionary events such as domestication and polyploidyisation was assessed. We detected bottlenecks associated with domestication, polyploidisation and selection, yet these constrictions were partially offset by mutations in the chloroplast SSR loci that generated new alleles. The discrete cpSSR alleles and haplotypes observed in T. urartu and Aegilops tauschii, combined with other species specific polymorphisms, provide very strong evidence that concur with current opinion that neither species was the maternal and thus cytoplasmic donor for polyploid wheats. Synthetic hexaploid wheats possessed the same chloroplast haplotypes as their tetraploid progenitors demonstrating how the novel synthetic wheat lines have captured chloroplast diversity from the maternal parents, the chloroplast is maternally inherited and novel alleles are not created by genomic rearrangements triggered by the polyploidisation event.  相似文献   
123.
Biological processes in soils are regulated in part by soil temperature, and there is currently considerable interest in obtaining robust information on the temperature sensitivity of carbon cycling process. However, very little comparable information exists on the temperature regulation of specific nitrogen cycling processes. This paper addresses this problem by measuring the temperature sensitivity of nitrogen cycling enzymes in soil. A grassland soil was incubated over a range of temperatures (?2 to 21 °C) reflecting 99 % of the soil temperature range during the previous 50 years at the site. After 7 and 14 days of incubation, potential activities of protease, amidase and urease were determined. Activities of protease and urease were positively related to temperature (activation energy; E a?=?49.7 and 73.4 kJ mol?1, respectively, and Q 10?=?2.97 and 2.78, respectively). By contrast, amidase activity was relatively insensitive to temperature, but the activity was significantly increased after the addition of glucose. This indicated that there was a stoichiometric imbalance with amidase activity only being triggered when there was a supply of exogenous carbon. Thus, carbon supply was a greater constraint to amidase activity than temperature was in this particular soil.  相似文献   
124.
  1. Knowledge of vital data such as growth and age at maturity is necessary to develop effective management strategies for endangered species. The Critically Endangered flapper skate (Dipturus intermedius) is the largest skate in the North Atlantic and growth information, necessary to assess key life-history traits, populations’ growth rates and anticipate their response to management measures, is still lacking.
  2. While classical age estimation methods used in fish generally require the analysis of calcified structures, destructive methods are incompatible with conservation objectives for this species. Taking advantage of the high recreational value of the flapper skate, this study uses citizen-science data originating from photo-identification of trophy pictures and tag–recapture data supported by anglers to estimate growth in this Critically Endangered species. Using the growth increments measured between recapture events, an individual-based Von Bertalanffy growth model was fitted to the data using Bayesian inference.
  3. The results confirm that the flapper skate is a long-lived species with ages estimated as >40 years for the largest individuals captured. Despite this longevity, the model reveals a relatively fast initial growth but relatively late ages at maturity and significant sex-related differences in both growth rate and maximum size.
  4. These results suggest that population growth rate, and therefore recovery, might be much slower than previously reported. By using citizen science this study provides the necessary information to begin understanding population dynamics and monitor the recovery of an iconic Critically Endangered species.
  相似文献   
125.
Nomadic pastoralism has been practised in Leliefontein for centuries. In 1984, the area was formally divided into 47 so‐called ‘economic units’ on the assumption that this agricultural approach would (a) promote development in the region and (b) introduce conservation management to these areas. The communal land tenure system was effectively abolished. We relate potential income from livestock farming in the region to costs of production and show that most of the 47 farming units of Leliefontein are, in fact, not economic farming units. Furthermore, there is little evidence to indicate that it has been the communal system per se that has been responsible for land degradation in the area. We point out that the change in land tenure, was based on technical considerations only, that the hidden costs were not adequately investigated and that the social ramifications were ignored.  相似文献   
126.
A marine fish oil, Marinol K (MO) and borage oil (BO) were used to formulate diets relatively rich in eicosapentaenoic acid [EPA; 20:5(n-3)] and -linolenic acid [GLA; 18:3(n-6)], respectively. The diets were fed to duplicate groups of juvenile turbot (Scophthalmus maximus) of initial weight 1.4 g for a period of 12 weeks. No differences were observed in final weights either between duplicate tanks or between dietary treatments. Mortalities in the MO-fed group were significantly greater than in the BO-fed group. In the MO-fed group, 7 out of 12 fish sampled for histological analysis showed a pronounced liver histopathology whereas only 1 of 12 fish sampled in the BO-fed group showed slight pathology. EPA levels were increased 2.2-fold and its elongation product, 22:5(n-3), was increased 1.8-fold while arachidonic acid [AA; 20:4(n-6)] was decreased by 30% in MO-fed fish compared to the initial carcass composition. GLA was increased 53-fold and its elongation product dihomo--linolenic acid [DHGLA; 20:3(n-6)] was increased 16-fold while AA was reduced by 90% in BO-fed fish compared to the initial carcass composition. The amount of triacylglycerol in liver of BO-fed fish was significantly greater than levels in MO-fed fish. The fatty acid compositions of individual phospholipids from liver showed marked differences between dietary treatments. Fish fed MO had significantly higher levels of the (n-3) polyunsaturated fatty acids (PUFA), 20:5(n-3), 22:5(n-3) and 22:6(n-3), and also significantly more 20:4(n-6) compared to BO-fed fish which had significantly higher 18:2(n-6), 18:3(n-6), 20:2(n-6) and 20:3(n-6). The composition of liver phosphatidylinositol was particularly unusual in BO-fed fish having DHGLA as the major C20 PUFA which was 2.2-fold greater than AA and 3.9-fold greater than EPA. This study demonstrates that the carcass composition of turbot can be altered, by means of dietary lipids, to contain increased levels of EPA and DHGLA which would be of potential benefit in human as well as in fish nutrition. However, caution should be exercised when using very highly unsaturated oils relatively rich in EPA which may generate histopathological lesions in the fish.Abbreviations AA arachidonic acid - ANOVA analysis of variance - BHT butylated hydroxytoluene - BO borage oil - DHA docosahexaenoic acid - DHGLA dihomo--linolenic acid - EPA eicosapentaenoic acid - GLA -linolenic acid - HPTLC high performance thin-layer chromatography - MO Marinol K - PC phosphatidylcholine - PE phosphatidylethanolamine - PI phosphatidylinositol - PS phosphatidylserine - PUFA polyunsaturated fatty acid - TLC thin-layer chromatography  相似文献   
127.
A new species of Echinoparyphium, E. montgomeriana, is described from Durban, South Africa. Certain unusual aspects of its morphology are discussed. The adult fluke is a parasite of the alimentary tract of birds. Its larval stages are common parasites of freshwater snails belonging to the family Planor-bidae including Buiinus africanus,the intermediate host ofSchistosoma haematobium and S. mattheei in the area. These intra-molluscan stages are shown to have a seasonal transmission cycle.  相似文献   
128.
OBJECTIVES: As a part of an ongoing project to develop a nutritional screening tool, we evaluated the performance of a semi-quantitative food-frequency questionnaire (FFQ) in terms of validity in a Sheffield Caucasian pregnant population using two different statistical approaches--the correlation coefficient and the limits of agreement (LOA). The FFQ was designed specifically for pregnant women and previously used in a large-scale study. DESIGN: A validation study. SETTING: A community-based field study of a general population of pregnant women booked for their first antenatal appointment at the Jessop Wing, Royal Hallamshire Hospital, Sheffield, UK. SUBJECTS: One hundred and twenty-three women of different socio-economic status, aged between 17 and 43 years, provided complete dietary data. RESULTS: The validity of the FFQ was tested against a series of two 24-hour recalls. As expected, the intakes of all examined nutrients, except for iodine, carotene, vitamin E, biotin, vitamin C and alcohol, were higher when determined by the FFQ than when determined by 24-hour recall. Pearson's correlation coefficient between the two methods ranged from 0.19 (added sugar, zinc) to 0.47 (Englyst fibre). The LOA were broader for some of the nutrients, e.g. protein, Southgate fibre and alcohol, and an increasing lack of agreement between the two methods was identified with higher dietary intakes. CONCLUSIONS: The FFQ gave useful estimates of the nutrient intakes of Caucasian pregnant women and appears to be a valid tool for categorising pregnant women according to dietary intake. The FFQ performed well for most nutrients and had acceptable agreement with the 24-hour recall.  相似文献   
129.
To predict recreational‐fishing impacts on freshwater fish species, it is important to understand the interplay between fish populations, anglers and management actions. We use an integrated bioeconomic model to study the importance of fish life‐history type (LHT) for determining (i) vulnerability to over‐exploitation by diverse angler types (generic, consumptive and trophy anglers), who respond dynamically to fishing‐quality changes; (ii) regulations [i.e., minimum‐size limits (MSLs) and licence densities] that maximize the social welfare of angler populations; and (iii) biological and social conditions resulting under such socially optimal regulations. We examine five prototypical freshwater species: European perch (Perca fluviatilis), brown trout (Salmo trutta), pikeperch (Sander lucioperca), pike (Esox lucius) and bull trout (Salvelinus confluentus). We find that LHT is important for determining the vulnerability of fish populations to overfishing, with pike, pikeperch, and bull trout being more vulnerable than perch and brown trout. Angler type influences the magnitude of fishing impacts, because of differences in fishing practices and angler‐type‐specific effects of LHT on angling effort. Our results indicate that angler types are systematically attracted to particular LHTs. Socially optimal minimum‐size limits generally increase with LHT vulnerability, whereas optimal licence densities are similar across LHTs. Yet, both regulations vary among angler types. Despite this variation, we find that biological sustainability occurs under socially optimal regulations, with one exception. Our results highlight the importance of jointly considering fish diversity, angler diversity and regulations when predicting sustainable management strategies for recreational fisheries. Failure to do so could result in socially suboptimal management and/or fishery collapse.  相似文献   
130.
Topical compounded Timentin® diluted with an inactive vehicle has been reported to be effective in the treatment of otitis externa caused by Pseudomonas aeruginosa. The aims of this study were to determine the biological efficacy of Timentin® (ticarcillin and clavulanic acid) when diluted in the carrier vehicle Methopt® against P. aeruginosa and to determine the efficacy and stability of Timentin® aqueous stock concentrate solution. Timentin® stock concentrate was tested against four P. aeruginosa isolates on days 0, 7, 14, 21 and 28; then after 2, 3, 4, 5, 6, 9 and 12 months of storage at 4 or ?20°C. The diluted Timentin®–Methopt® solutions were tested against all isolates after 0, 2, 4, 6, 8, 10, 12, 14, 17, 21, 24 and 28 days of storage at 24 or 4°C. Minimal inhibitory concentration (MIC) levels for all strains were determined using the broth microdilution method. The MIC of the stock solution remained relatively constant and acceptable throughout the study when stored at ?20°C and was also acceptable for shorter time periods (6–9 months) when stored at 4°C. The MIC for the diluted Timentin®–Methopt® solution remained relatively constant and acceptable throughout the study for all four bacterial strains, with no difference between the solutions stored at 4 or 24°C. The results of this study indicate that storage of the Timentin® stock solution at ?20°C does not compromise efficacy for at least 12 months and that Timentin® diluted in Methopt® was stable for 28 days when stored at either 4 or 24°C.  相似文献   
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