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61.
A growth trial was conducted with the aim of developing a practical, environmentally sustainable and cost-effective plant-protein-based diet for Senegalese sole juveniles without compromising growth or protein deposition. A reference diet contained fish meal as the main protein source (F45, containing 37% fish meal and 45% of the dietary protein being from marine sources) and four plant-protein diets either containing 5% (F15) or no fishmeal (F5). The F15 diet also contained 5% hydrolysed protein (CPSP) and 5% squid meal while the F5 contained 2% CPSP and 3% squid meal. The rest of the protein derived from a blend of soybean meal, corn and wheat gluten. Thus, the plant-protein fraction in these test diets ranged from 70–80%. The plant-based diets were supplemented either with a mixture of all indispensable amino acids (IAA) (F15 + IAA, F5 + IAA) or only with lysine (F15 + Lys, F5 + Lys). Triplicate groups of 18 fish of 9.5 g were fed by automatic feeders that distributed 8 meals over 24 h, for a period of 12 weeks.At the end of the experiment mean body weight more than tripled in all treatments (32.8 to 42.7 g). Sole fed with either F15 + Lys (33.3 g) or F5 + Lys (32.8 g) grew significantly less than all the other treatments. Protein productive value (PPV) was significantly lower in sole fed with F5 + Lys (0.30) than in all other treatments (0.34 to 0.37) while F5 + Lys (0.23) energy productive value (EPV) just differed significantly from fish fed with F45 (0.38). Moreover, protein gain (P gain) was significantly higher in sole fed with diet supplemented with all IAA (F15 + IAA and F5 + IAA) than those fed with diet with only lysine added (F15 + Lys and F5 + Lys) and a strong positive correlation between P gain and methionine (Met) intake was found (P = 0.00002).Dietary fish meal protein can be totally replaced by a mixture of plant-protein sources without any adverse effects on growth, feed or protein utilization provided the dietary amino acids are balanced. The test diet F5 + IAA seems a good alternative to use in Senegalese sole production when the main objective is to substitute an increasingly scarce ingredient – fish meal – without compromising fish performance. Moreover, for large-scale production feeds the F15 + Lys putatively supplemented with Met, Thr and Arg would be recommended.  相似文献   
62.
Solid phase microextraction (SPME) coupled to gas chromatography-mass spectrometry (GC-MS) was employed for the headspace determination of the volatile organic fraction emitted by two of the most common Mediterranean demosponges, Ircinia variabilis and Sarcotragus spinosulus, and of indole and some biogenic amines released by sponges in an aqueous medium. A total of 50/30 µm divinylbenzene/carboxen/polydimethylsiloxane and 75 µm carboxen/polydimethylsiloxane fibers were used for the headspace extraction of low molecular weight sulfur compounds from a hermetically sealed vial containing sponge fragments, while the direct immersion determination of indole and biogenic amines was performed. The biogenic amines were extracted after in-solution derivatization with isobutyl chloroformate. All analytical parameters (linearity, limits of detection, and quantification, precision, and recovery) were evaluated for indole and biogenic amines. SPME-GC-MS proved to be a reliable means of highlighting the differences between molecules released by different sponges, principally responsible for their smell. The combined approaches allowed the identification of several volatile compounds in the headspace and other molecules released by the sponges in an aqueous medium, including indole and the BAs cadaverine, histamine, isobutylamine, isopentylamine, propylamine, 2-phenylethylamine, putrescine and tryptamine. The results obtained represent a further contribution to the picture of odoriferous molecules secreted by sponges.  相似文献   
63.
Six adult Zébu cattle were used for a study of the histologic structure of the epididymus. Tissues were fixed in neutral formalin or in Bouin's solution. Tissues were prepared with parafin sectioning and stained with hematoxylin and eosin, Masson and Mallory's trichrome stain and with aldehyde fuchsin and Gomori's argentamine stains. The structure of the connective tissue stroma is described and compared with that of other mammals. The presence of smooth muscle within the stroma and within the tunica albuginea is described for the Zébu.  相似文献   
64.
Blackspot seabream, Pagellus bogaraveo (Brunnich), has been identified as a potential species to diversify European aquaculture production. Although rearing aspects have been widely investigated, little information exists on the nutritional requirements for this species. The aim of this study was to build up information on the activity of digestive enzymes at certain developmental stages of blackspot seabream in order to understand the nutritional needs of larvae and post larvae. Fish larvae were reared from hatching to 55 days after hatching (dah), and the feeding plan consisted in rotifers (5–35 dah), Artemia naupli (30–35 dah) metanaupli (35–45) and Gemma microdiet (45–55 dah). At 7, 11, 21, 45 and 55 days after hatching (dah), pooled samples of fish larvae were collected for analysis of trypsin, amylase, lipase, alkaline phosphatase and leucine–alanine peptidase activity. Up to 21 dah, the whole larvae body was used for enzymatic analysis, whereas in older larvae only the dissected abdominal cavity was used. Blackspot seabream body dry weight growth was exponential, increasing from 60 μg at 5 dah to 30±9.7 mg at 55 dah. Amylase specific activity decreased significantly during development, exhibiting at 11 dah (0.6 U mg?1 protein) an average value 2.7 times lower than at 7 dah, and remaining stable between 45 and 55 dah (0.7 U mg protein?1). Trypsin specific activity remained constant until 21 dah (between 38 and 44 mU mg protein?1), which could be related to the larvae feeding regime. At later stages of development, lipase‐specific activity exhibited a significant increase (P<0.05), being three times higher at 55 dah (8 U mg protein?1) than at 45 dah. The total activity of the studied digestive enzymes increased significantly during larval development (until 21 dah), whereas afterwards only lipase and leucine–alanine peptidase increased significantly between 45 and 55 dah. The pattern of digestive enzymes activity was related to organogenesis and the type of food used at different developmental stages.  相似文献   
65.
Quantitation of nine organic acids in wild mushrooms   总被引:3,自引:0,他引:3  
The organic acids composition of six wild edible mushroom species (Amanita caesarea, Boletus edulis, Gyroporus castaneus, Lactarius deliciosus, Suillus collinitus, and Xerocomus chrysenteron) was determined by an HPLC-UV detector method. The results showed that all of the samples presented a profile composed of at least five organic acids: citric, ketoglutaric, malic, succinic, and fumaric acids. Several samples also contained oxalic, ascorbic, quinic, and shikimic acids. In a general way, the quantitation of the identified compounds indicated that malic acid, followed by the pair citric plus ketoglutaric acids, were the main compounds in the analyzed species, with the exception of A. caesarea, in which malic and ascorbic acids were the most abundant compounds. The relative amounts and the presence/absence of each identified compound may be useful for the differentiation of the species.  相似文献   
66.
OBJECTIVE: We aimed at examining the association between dietary constituents and risk of cutaneous melanoma. DESIGN: In an area of northern Italy we recruited 59 newly diagnosed melanoma patients and 59 age- and sex-matched population controls, to whom we administered a validated semi-quantitative food-frequency questionnaire. RESULTS: We found an excess risk of melanoma in subjects with a higher energy-adjusted intake of total polyunsaturated fatty acids and, in particular, of linoleic acid (relative risk = 2.16 for intake in the highest tertile compared with the lowest tertile, P for linear trend = 0.061). Conversely, disease risk was inversely associated with the consumption of soluble carbohydrates (relative risk = 0.34 for intake in the upper vs. the lowest tertile adjusting for total energy intake, P for linear trend = 0.046). No other dietary factors, including alcohol, vitamins and trace elements, correlated with melanoma risk. The association of melanoma risk with linoleic acid and soluble carbohydrates intakes was further strengthened in multivariate analysis, and when analysis was limited to females. CONCLUSIONS: Overall, these results indicate that an excess energy-adjusted intake of linoleic acid and a lower consumption of soluble carbohydrates may increase melanoma risk.  相似文献   
67.
OBJECTIVE: To identify factors potentially associated with weight retention measured 9 months after childbirth. DESIGN: Prospective study with four follow-up waves in time (0.5, 2, 6 and 9 months postpartum). SETTING: Rio de Janeiro, Brazil. SUBJECTS AND METHODS: Two hundred and sixty-six Brazilian women of childbearing age. Analysis was based on hierarchical logistic regression. The dependent variable was weight retention and was defined as the difference between weight at 9 months postpartum and pre-pregnancy weight, with a dichotomised cut-off at 7.5 kg. Covariates included demographic and socio-economic data, obstetric history, anthropometric data, and data on the infant. These data were grouped in blocks and ordered according to their influence on the dependent variable. RESULTS: Of the women studied, 19.2% presented weight retention values > or =7.5 kg. According to the logistic regression analysis, the following variables remained associated with weight retention > or =7.5 kg: total family income, difficulty or inability to read a letter, age category > or =30 years, age at first childbirth <23 years, gestational weight gain > or =12 kg, body fat at baseline > or =30% and infant birth weight <3500 g. Infant hospitalisation was only marginally significant. CONCLUSIONS: Determinant factors identified by the analysis highlight the need for nutritional intervention policies during pregnancy and in the first months postpartum as a way of minimising obesity and the diseases resulting from it.  相似文献   
68.
Poor teat and udder structure, frequently associated with older cows, impact cow production and health as well as calf morbidity and mortality. However, producer culling, for reasons including age, production, feed availability, and beef markets, creates a bias in teat (TS) and udder scores (US) assessed and submitted to the Canadian Angus Association for genetic evaluations toward improved mammary structure. In addition, due to the infancy of the reporting program, repeated scores are rare. Prior to the adoption of genetic evaluations for TS and US in Canadian Angus cattle, it is imperative to verify that TS and US from young cows are the same traits as TS and US estimated on mature cows. Genetic parameters for TS and US from all cows (n = 4,192) and then from young cows (parities 1 and 2) and from mature cows (parity ≥ 4) were estimated using a single-trait animal model. Genetic correlations for the traits between the two cow age groups were estimated using a two-trait animal model. Estimates of heritability (posterior SD [PSD]) were 0.32 (0.07) and 0.45 (0.07) for young TS and US and 0.27 (0.07) and 0.31 (0.07) for mature TS and US, respectively. Genetic correlation (PSD) between the young and mature traits was 0.87 (0.13) for TS and 0.40 (0.17) for US. Genome-wide association studies were used to further explore the genetic and biological commonalities and differences between the two groups. Although there were no genes in common for the two USs, 12 genes overlapped for TS in the two cow age groups. Interestingly, there were also 23 genes in common between TS and US in mature cows. Based on these findings, it is recommended that producers collect TS and US on their cow herd annually.  相似文献   
69.
The development of feeding behaviour in two rainbow trout strains and their hybrid was compared at the transition from endogenous nutrition to exogenous feeding. After 60 min of acclimatization, the swimming pattern, spatial distribution, agonistic behaviour and snapping of fish were quantified by making 5-min observations on groups of five fish. Behavioural patterns were recorded in four replicate groups per treatment, before and after the introduction of dry trout feed or Artemia nauplii (actometric tests) or extracts of these (olfactometric tests). Fish of the slow growing strain were less active than those of the other two strains. Greater swimming activity observed in the fish of the fast growing strain was associated with more rapid feeding and a higher number of snapping responses. Such behavioural precocity is of interest because it could provide the basis for the growth differences between the fast and slow growing strains.  相似文献   
70.
  1. This study presents data on a local population of short-beaked common dolphin monitored in the waters off Ischia Island (Gulf of Naples, Italy) over a 16-year period (2000-2015). We examine dolphin occurrence and distribution and perform photoidentification analysis.
  2. The data presented support the hypothesis that the waters around Ischia Island represent a feeding area, as well as a calving and an important nursery area for this local population, providing favourable conditions in which to give birth and raise calves.
  3. The levelling-off of the photoidentification curves together with the continuous decline of the encounter rate lead us to believe that the area has been a hotspot for a local population (mainly resident) for years and that now this population is dying (has died) or is moving (has moved) to other locations.
  4. Several expanding human activities at sea have the potential to impact on the common dolphin in the study area, the most significant possibly being habitat disturbance and degradation (including traffic and noise pollution) and overexploitation of food resources by the fishery.
  5. The data presented in this study offer a strong argument for explicit and urgent population-specific conservation and management strategies to be developed and applied locally for common dolphins, considering that they rely on the region for important biological processes.
  相似文献   
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