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31.
OBJECTIVE: To pilot the design and methodology for a large randomised controlled trial (RCT) of two interventions to promote healthier food purchasing: culturally appropriate nutrition education and price discounts. DESIGN: A 12-week, single-blind, pilot RCT. Effects on food purchases were measured using individualised electronic shopping data ('Shop 'N Go' system). Partial data were also collected on food expenditure at other (non-supermarket) retail outlets. SETTING: A supermarket in Wellington, New Zealand. PARTICIPANTS: Eligible customers were those who were the main household shoppers, shopped mainly at the participating store, and were registered to use the Shop 'N Go system. Ninety-seven supermarket customers (72% women; age 40 +/- 9.6 years, mean +/- standard deviation) were randomised to one of four intervention groups: price discounts, nutrition education, a combination of price discounts and nutrition education, or control (no intervention). RESULTS: There was a 98% follow-up rate of participants, with 85% of all reported supermarket purchases being captured via the electronic data collection system. The pilot did, however, demonstrate difficulty recruiting Maori, Pacific and low-income shoppers using the electronic register and mail-out. CONCLUSIONS: This pilot study showed that electronic sales data capture is a viable way to measure effects of study interventions on food purchases in supermarkets, and points to the feasibility of conducting a large-scale RCT to evaluate the effectiveness of price discounts and nutrition education. Recruitment strategies will, however, need to be modified for the main trial in order to ensure inclusion of all ethnic and socio-economic groups.  相似文献   
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33.
OBJECTIVE: To determine the prevalence of pedunculated lipomas and identify risk factors affecting postoperative complications and survival in horses at a veterinary teaching hospital undergoing surgery for colic caused by pedunculated lipomas. DESIGN: Retrospective study. ANIMALS: 102 horses with a diagnosis of pedunculated lipoma. PROCEDURE: Age, breed, weight, and sex of horses with pedunculated lipomas were compared with the total equine hospital population and the population of horses admitted for abdominal surgery during the same period. Follow-up information was obtained by reevaluation or contact with owners via telephone or written request. RESULTS: Prevalence of pedunculated lipomas as a reason for abdominal surgery in horses, compared with the population of horses with and without lipomas admitted for abdominal surgery, was 10%. Castrated male Saddlebred and Arabian horses > 14 years old were identified as being at risk for developing pedunculated lipomas. Postoperative complications were detected in 72% of horses with pedunculated lipomas. Variables associated with low survival rates included surgery before 1992, heart rate > 80 beats/min, abnormal color of abdominal fluid, pale mucous membranes, surgery requiring intestinal resection, and inability to attain a mean arterial pressure > or = 100 mm Hg. Horses undergoing surgery from 1992 to 1996, weighing < 409 kg (900 lb), or requiring jejunojejunal anastomosis had a high survival rate. CONCLUSIONS AND CLINICAL RELEVANCE: Although many of the variables reflected the health of the horse at the time of surgery, results may help veterinarians recognize risk factors associated with development of pedunculated lipomas and better predict the outcome of horses undergoing surgery for colic caused by pedunculated lipomas.  相似文献   
34.
Whole grains contain all parts of the grain: the endosperm, germ, and bran. Whole grains are rich in fermentable carbohydrates that reach the gut: dietary fiber, resistant starch, and oligosaccharides. Most research that supports the importance of grains to gut health was conducted with isolated fiber fractions, rather than whole grains. Whole grains are an important source of dietary fiber and grain fibers such as wheat, oats, barley, and rye increase stool weight, speed intestinal transit, get fermented to short chain fatty acids, and modify the gut microflora. Wheat bran is particularly effective in increasing stool weight; wheat bran increases stool weight by a ratio of 5:1. In contrast, many novel fibers that are easily incorporated into beverages and foods increase stool weight only on a ratio of 1:1. In vitro fermentation studies with whole grains have been published. Carbohydrates of oat bran (rich in β‐glucan) were consumed by bacteria faster than those of rye and wheat brans (rich in arabinoxylan). Grain fibers were fermented more slowly than inulin, causing less gas production. Wheat is particularly high in fructo‐oligosaccharides, while wheat germ is high in raffinose oligosaccharides. Some in vivo studies show the prebiotic potential of whole grains. Whole grain breakfast cereal was more effective than wheat bran breakfast cereal as a prebiotic, increasing fecal bifidobacteria and lactobacilli in human subjects. Wheat bran consumption increased stool frequency. Thus, the gut enhancing effects of cereal fibers are well known. Limited data exist that whole grains alter gut health.  相似文献   
35.
Echium oil (EO) is a vegetable oil in which percentages of stearidonic acid (STA, 18:4n‐3) often exceed those of its n‐6 series equivalent γ‐linolenic acid (GLA, 18:3n‐6). Stearidonic acid is elongated to 20:4n‐3 in fish cell cultures, suggesting that EO could be included in diets for marine fish to increase tissue 20:4n‐3 and 20:3n‐6 and, thereby, modulate eicosanoid metabolism. Thus, the present study aimed to test the hypotheses that dietary EO would increase tissue 20:4n‐3 and 20:3n‐6 and modulate immune function and eicosanoid production in juvenile Atlantic cod (Gadus morhua L.) fed a diet where fish oil (FO) was replaced by EO. Duplicate groups of juvenile cod (initial weight ca. 4 g) were fed for 18 weeks on fish meal‐based diets (55% protein and 16% lipid) that differed in oil source (FO or EO). There were no significant differences in growth and feed efficiency, hepato‐somatic index, percentages of liver and flesh lipids and lipid class compositions for cod fed FO and EO. Percentages of 18:4n‐3, 18:3n‐6 and 20:3n‐6 in the total lipids of flesh and liver were higher, and percentages of 20:5n‐3 and 20:4n‐6 were both lower in fish fed EO than in those given FO. In flesh, the increased 18:3n‐6 and 18:4n‐3 were primarily located in phosphatidylcholine and, to a lesser extent, phosphatidylethanolamine, whereas 20:3n‐6 concentration was highest in phosphatidylinositol. Desaturation of 18:3n‐3 (to tetraene products) and 20:5n‐3 to 22:6n‐3 in hepatocytes was very low but was increased by dietary EO. Echium oil significantly decreased the production of prostaglandin F from gill cells stimulated with calcium ionophore A23187, and reduced head kidney macrophage activity, but had no effect on serum lysozyme activity or basic haematology. In conclusion, dietary EO may have beneficial effects on some immune parameters including eicosanoid metabolism in marine fish although this may be primarily because of decreased 20:4n‐6 rather than increasing tissue levels of 20:3n‐6 or 20:4n‐3.  相似文献   
36.
Remote sensing technology offers the ability to derive information on freshwater fish habitats across broad geographic areas and has the potential to transform approaches to monitoring. However, the numerous platforms, sensors and analytical software that are available may overwhelm those interested in utilizing this important technology and thus limit its broad application and uptake. Our review is intended to shed light on the capacity of this technology to transform freshwater fish habitat monitoring by examining the fundamental characteristics of the major remote sensing technologies that have been used for characterizing freshwater habitats, conducting a systematic literature review of studies that have used remote sensing technologies to characterize freshwater fish habitats and, highlighting some of the key habitat features, fish species and regions, that have been examined. Lastly, we identify the relative strengths and weaknesses of the various remote sensing technologies that can be used, recommend future research that could help improve the use of these technologies, and, provide a series of important considerations for those who are interested in utilizing these technologies for freshwater fish habitat characterization.  相似文献   
37.
Understanding cancer pathogenesis requires knowledge of not only the specific contributory genetic mutations but also the cellular framework in which they arise and function. Here we explore the clonal evolution of a form of childhood precursor-B cell acute lymphoblastic leukemia that is characterized by a chromosomal translocation generating a TEL-AML1 fusion gene. We identify a cell compartment in leukemic children that can propagate leukemia when transplanted in mice. By studying a monochorionic twin pair, one preleukemic and one with frank leukemia, we establish the lineal relationship between these "cancer-propagating" cells and the preleukemic cell in which the TEL-AML1 fusion first arises or has functional impact. Analysis of TEL-AML1-transduced cord blood cells suggests that TEL-AML1 functions as a first-hit mutation by endowing this preleukemic cell with altered self-renewal and survival properties.  相似文献   
38.
Degenerative disorders of motor neurons include a range of progressive fatal diseases such as amyotrophic lateral sclerosis (ALS), spinal-bulbar muscular atrophy (SBMA), and spinal muscular atrophy (SMA). Although the causative genetic alterations are known for some cases, the molecular basis of many SMA and SBMA-like syndromes and most ALS cases is unknown. Here we show that missense point mutations in the cytoplasmic dynein heavy chain result in progressive motor neuron degeneration in heterozygous mice, and in homozygotes this is accompanied by the formation of Lewy-like inclusion bodies, thus resembling key features of human pathology. These mutations exclusively perturb neuron-specific functions of dynein.  相似文献   
39.
Many oomycete and fungal plant pathogens are obligate biotrophs, which extract nutrients only from living plant tissue and cannot grow apart from their hosts. Although these pathogens cause substantial crop losses, little is known about the molecular basis or evolution of obligate biotrophy. Here, we report the genome sequence of the oomycete Hyaloperonospora arabidopsidis (Hpa), an obligate biotroph and natural pathogen of Arabidopsis thaliana. In comparison with genomes of related, hemibiotrophic Phytophthora species, the Hpa genome exhibits dramatic reductions in genes encoding (i) RXLR effectors and other secreted pathogenicity proteins, (ii) enzymes for assimilation of inorganic nitrogen and sulfur, and (iii) proteins associated with zoospore formation and motility. These attributes comprise a genomic signature of evolution toward obligate biotrophy.  相似文献   
40.
There is a wide variety of cancer types yet, all share some common cellular and molecular behaviors. Most of the chemotherapeutic agents used in cancer treatment are designed to target common deregulated mechanisms within cancer cells. Many healthy tissues are also affected by the cytotoxic effects of these chemical agents. Fucoidan, a natural component of brown seaweed, has anti-cancer activity against various cancer types by targeting key apoptotic molecules. It also has beneficial effects as it can protect against toxicity associated with chemotherapeutic agents and radiation. Thus the synergistic effect of fucoidan with current anti-cancer agents is of considerable interest. This review discusses the mechanisms by which fucoidan retards tumor development, eradicates tumor cells and synergizes with anti-cancer chemotherapeutic agents. Challenges to the development of fucoidan as an anti-cancer agent will also be discussed.  相似文献   
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