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141.

The milk intake in piglets from four lactating sows was measured in three 48 h periods, starting on days 3, 10 and 17 of lactation, using the deuterium oxide (D 2 O) dilution technique. The milk intake was estimated from the water turnover in the piglets corrected for the production of metabolic water. The water turnover was estimated from the water dilution space and the fractional turnover of body water, determined by the rate of D 2 O dilution. To determine the magnitude of isotopic recycling, a randomly selected piglet in each litter was not enriched with D 2 O. Milk production of the four lactating sows was also measured by the weigh-suckle-weigh (WSW) method on days 4, 11 and 18 of lactation. The average daily milk production determined by the D 2 O dilution technique (9.91 - 0.69 kg) was higher ( P <0.05) than that determined by the uncorrected WSW method (8.65 - 0.81 kg). Different procedures for selecting piglets were evaluated to obtain the best possible estimation of total milk production from three piglets in each litter. The total milk production of a sow based on three piglets in the litter was obtained from a quadratic model of the relationship between milk intake and daily gain. When the daily gain of all piglets were known the Pearson correlation between milk production determined for the whole litter ( n -1) and only three median piglets was 0.98.  相似文献   
142.
CD36 is a scavenger receptor involved in lipid uptake and inflammation. Recently, non-cell-bound CD36 (sCD36) was identified in plasma and suggested to be a marker of lipid accumulation in the vessel wall. Marine n-3 polyunsaturated fatty acids (PUFA) may have cardioprotective effects. This study evaluated the effect of marine n-3 PUFA on sCD36 levels in overweight subjects. Fifty overweight subjects were randomized to 1.1 g of n-3 PUFA or 2 g of olive oil daily for six weeks. Neutrophils were isolated at baseline and after six weeks of treatment while an adipose tissue biopsy was obtained at baseline. The content of n-3 PUFA in adipose tissue and neutrophils was analyzed by gas chromatography, while plasma levels of sCD36 were determined using an enzyme-linked immunosorbent assay (ELISA). After six weeks of supplement plasma sCD36 did not differ between supplements (P = 0.18). There was no significant correlation between plasma sCD36 levels and n-3 PUFA in neutrophils at baseline (r = −0.02, P = 0.88), after six weeks supplement (r = −0.03, P = 0.85) or in adipose tissue (r = 0.14, P = 0.34). This study therefore does not provide evidence for a cardioprotective effect of n-3 PUFA acting through a CD36-dependent mechanism.  相似文献   
143.
144.
Streptococcus equi subsp. zooepidemicus is the pathogen most commonly isolated from the uterus of mares. S. zooepidemicus is an opportunistic pathogen and part of the resident flora in the caudal reproductive tract. The aim of this study was to investigate whether a genotypically distinct subpopulation of S. zooepidemicus is associated with endometritis in the mare, by genotyping and comparing uterine S. zooepidemicus strains with isolates from the vagina and clitoral fossa. Mares with (n = 18) or without (n = 11) clinical symptoms of endometritis were included. Uterine samples were obtained using a guarded endometrial biopsy punch, whereas a swab was used to recover samples from the cranial vagina and the clitoral fossa. If S. zooepidemicus was present, up to three colonies were selected from each anatomical location (max. 9 isolates per mare). Bacterial isolates were characterized by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). S. zooepidemicus was isolated from the endometrium of 12 mares. A total of 88 isolates were analyzed by PFGE: 31 from the endometrium, 26 from the cranial vagina and 31 isolates from the clitoral fossa. For MLST 21 isolates were chosen. Results demonstrated a higher genetic similarity of the isolates obtained from infectious endometritis compared to isolates obtained from the caudal reproductive tract. In conclusion, we demonstrate for the first time that a genetically distinct group of S. zooepidemicus is associated with infectious endometritis in the mare.  相似文献   
145.
The current knowledge of in vitro adherence of Staphylococcus pseudintermedius to canine corneocytes is limited to comparative analyses between strains, staphylococcal species or corneocytes collected from different breeds, body sites and hosts. However, the role played by colonization status of corneocyte donors remains unknown. The aim of this study was to evaluate the adherence properties of commensal S. pseudintermedius strains to corneocytes collected from dogs with different colonization status. For this purpose, corneocytes were collected from five dogs that were classified as persistently colonized (D1 and D2), intermittently colonized (D3 and D4) or non-colonized (D5) on the basis of the results of a previous longitudinal study. Adherence to corneocytes originating from each of the five dogs was assessed by an in vitro adhesion assay using four genetically unrelated strains isolated from the colonized dogs (S1 to S4). Irrespective of their host of origin, all strains adhered significantly better to corneocytes from D1 and D2 than to corneocytes from D3, D4 and D5 (P < 0.0001). The mean count of cells adhering to corneocytes from persistently colonized dogs was on average three times higher than the mean count using corneocytes from the other dogs. A significant difference between strains was only observed for one strain-corneocyte combination (S2-D4), indicating that S. pseudintermedius adherence to corneocytes is driven by host factors and only marginally influenced by strain factors. This finding has important implications for understanding and preventing S. pseudintermedius skin colonization and infection.  相似文献   
146.
In 2 experiments, 48 weanling (initial BW: 13.5 ± 2.4 kg, Exp. 1) and 24 growing pigs (initial BW: 36.2 ± 4.0 kg, Exp. 2) were used to determine effects of a novel bacterial 6-phytase expressed in Aspergillus oryzae on the apparent total tract digestibility (ATTD) of phosphorus and calcium in corn-soybean meal diets fed to weanling and growing pigs. In Exp. 1 and 2, pigs were randomly allotted to 6 dietary treatments using a randomized complete block design and a balanced 2 period changeover design, respectively. In both experiments, 6 diets were formulated. The positive control diet was a corn-soybean meal diet with added inorganic phosphorus (Exp. 1: 0.42 and 0.86% standardized total tract digestible phosphorus and total calcium, respectively; Exp. 2: 0.32 and 0.79% standardized total tract digestible phosphorus and total calcium, respectively). A negative control diet and 4 diets with the novel phytase (Ronozyme HiPhos, DSM Nutritional Products Inc., Parsippany, NJ) added to the negative control diet at levels of 500, 1,000, 2,000, and 4,000 phytase units (FYT)/kg were also formulated. In Exp. 1, the ATTD of phosphorus was greater (P < 0.01) for the positive control diet (60.5%) than for the negative control diet (40.5%), but increased (linear and quadratic, P < 0.01) as phytase was added to the negative control diet (40.5% vs. 61.6%, 65.1%, 68.7%, and 68.0%). The breakpoint for the ATTD of phosphorus (68.4%) was reached at a phytase inclusion level of 1,016 FYT/kg. In Exp. 2, the ATTD of phosphorus was greater (P < 0.01) for the positive control diet (59.4%) than for the negative control diet (39.8%) and increased (linear and quadratic, P < 0.01) as phytase was added to the negative control diet (39.8% vs. 58.1%, 65.4%, 69.1%, and 72.8%). The breakpoint for the ATTD of phosphorus (69.1%) was reached at a phytase inclusion level of 801 FYT/kg. In conclusion, the novel bacterial 6-phytase improved the ATTD of phosphorus and calcium in both weanling and growing pigs. The optimum level of inclusion for this phytase is 800 to 1,000 FYT/kg of complete feed to maximize ATTD of phosphorus and calcium in weanling and growing pigs.  相似文献   
147.
Infections with Mycobacterium avium subsp. paratuberculosis (MAP) can be latent for years without affecting the animal, but the animal may become infectious or clinical at some point. Diagnosis of paratuberculosis can be a challenge primarily in latent stages of the infection, and different diagnosis interpretations are usually required by the variety of decision makers. The objective of this paper was to provide a critical review of reported accuracies of ELISA tests, interferon-gamma assays (IFN-gamma) and faecal culture (FC) techniques used for diagnosis of three defined target conditions: MAP infected, MAP infectious and MAP affected animals. For each animal species, target condition and diagnostic test-type, sensitivities (Se) and specificities (Sp) were summarised based on a systematic, critical review of information in literature databases. The diagnostic test information often varied substantially for tests of the same type and make, particularly ELISA, which was the most frequently reported test-type. Comparison of the various tests accuracies was generally not possible, but stratification of test-evaluations by target condition improved the interpretation of the test accuracies. Infectious and affected animals can often be detected, but Se for infected animals is generally low. A main conclusion of the review was that the quality of design, implementation and reporting of evaluations of tests for paratuberculosis is generally poor. Particularly, there is a need for better correspondence between the study population and target population, i.e. the subjects chosen for test evaluation should reflect the distribution of animals in the population where the test is intended to be used.  相似文献   
148.
149.
The concept of foetal programming(FP) originated from human epidemiological studies, where foetal life nutrition was linked to health and disease status later in life. Since the proposal of this phenomenon, it has been evaluated in various animal models to gain further insights into the mechanisms underlying the foetal origins of health and disease in humans. In FP research, the sheep has been quite extensively used as a model for humans. In this paper we will review findings mainly from our Copenhagen sheep model, on the implications of late gestation malnutrition for growth, development, and metabolic and endocrine functions later in life, and discuss how these implications may depend on the diet fed to the animal in early postnatal life. Our results have indicated that negative implications of foetal malnutrition, both as a result of overnutrition and, particularly, late gestation undernutrition, can impair a wide range of endocrine functions regulating growth and presumably also reproductive traits. These implications are not readily observable early in postnatal life, but are increasingly manifested as the animal approaches adulthood. No intervention or cure is known that can reverse this programming in postnatal life. Our findings suggest that close to normal growth and slaughter results can be obtained at least until puberty in animals which have undergone adverse programming in foetal life, but manifestation of programming effects becomes increasingly evident in adult animals.Due to the risk of transfer of the adverse programming effects to future generations, it is therefore recommended that animals that are suspected to have undergone adverse FP are not used for reproduction. Unfortunately, no reliable biomarkers have as yet been identified that allow accurate identification of adversely programmed offspring at birth,except for very low or high birth weights, and, in pigs, characteristic changes in head shape(dolphin head). Future efforts should be therefore dedicated to identify reliable biomarkers and evaluate their effectiveness for alleviation/reversal of the adverse programming in postnatal life. Our sheep studies have shown that the adverse impacts of an extreme, high-fat diet in early postnatal life, but not prenatal undernutrition, can be largely reversed by dietary correction later in life. Thus, birth(at term) appears to be a critical set point for permanent programming in animals born precocial,such as sheep. Appropriate attention to the nutrition of the late pregnant dam should therefore be a priority in animal production systems.  相似文献   
150.
The STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) statement was first published in 2007 and again in 2014. The purpose of the original STROBE was to provide guidance for authors, reviewers and editors to improve the comprehensiveness of reporting; however, STROBE has a unique focus on observational studies. Although much of the guidance provided by the original STROBE document is directly applicable, it was deemed useful to map those statements to veterinary concepts, provide veterinary examples and highlight unique aspects of reporting in veterinary observational studies. Here, we present the examples and explanations for the checklist items included in the STROBE‐Vet Statement. Thus, this is a companion document to the STROBE‐Vet Statement Methods and process document, which describes the checklist and how it was developed.  相似文献   
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