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81.
OBJECTIVE: To compare biomaterials used in orthopedics with respect to in vitro cell viability and cell retention and to in vivo tissue healing and regeneration. ANIMALS: 65 adult female Sprague-Dawley rats and synovium, tendon, meniscus, and bone marrow specimens obtained from 4 adult canine cadavers. PROCEDURES: Synovium, tendon, meniscus, and bone marrow specimens were used to obtain synovial fibroblasts, tendon fibroblasts, meniscal fibrochondrocytes, and bone marrow-derived connective tissue progenitor cells for culture on 5 biomaterials as follows: cross-linked porcine small intestine (CLPSI), non-cross-linked human dermis, cross-linked porcine dermis, non-cross-linked porcine small intestine (NCLPSI), and non-cross-linked fetal bovine dermis. After 1 week of culture, samples were evaluated for cell viability, cell density, and extracellular matrix production. Biomaterials were evaluated in a 1-cm(2) abdominal wall defect in rats. Each biomaterial was subjectively evaluated for handling, suturing, defect fit, and ease of creating the implant at the time of surgery, then grossly and histologically 6 and 12 weeks after surgery. RESULTS: All biomaterials allowed for retention of viable cells in culture; however, CLPSI and NCLPSI were consistently superior in terms of cell viability and cell retention. Cell infiltration for NCLPSI was superior to other biomaterials. The NCLPSI appeared to be replaced with regenerative tissue most rapidly in vivo and scored highest in all subjective evaluations of ease of use. CONCLUSIONS AND CLINICAL RELEVANCE: These data suggested that NCLPSI and CLPSI have favorable properties for further investigation of clinical application in orthopedic tissue engineering.  相似文献   
82.
An adult dairy cow fatally affected with winter dysentery was investigated pathologically and virologically. The cow had severe anemia and diarrhea with massive blood. Pathologically, the loss of surface epithelial cells and necrosis of crypt epithelial cells in the large intestine were observed. Bovine coronavirus (BCV) antigen was observed in necrotic crypt epithelial cells of the large intestine. Virus particles were found in the necrotic epithelial cells of the large intestine. Virologically, BCV was isolated from the feces of the dead cow. The dead cow had no serum antibody against BCV although the co-habitants did. These suggest that severe infection of BCV in the cow without the BCV antibody accompanied by severe hemorrhagic anemia resulted in the cow's death.  相似文献   
83.
The effect of algae with different DHA contents used for the enrichment of rotifers on the growth performance, survival, and swim bladder inflation of larval amberjack Seriola dumerili was investigated. Rotifers were enriched with freshwater Chlorella vulgaris containing three levels of DHA (rotifer containing DHA 0.04, 0.60, 1.32?g DHA 100?g?1 DM) and Nannochloropsis (0.04?g DHA 100?g?1 DM; 2.54?g EPA 100?g?1DM). The larvae were fed the enriched rotifers in triplicate from 3?days post-hatch for 7?days in static condition. The same algae used for rotifer enrichment were supplied to the larval tanks. Growth and survival rate of fish fed the rotifers enriched with Nannochloropsis were higher than those of fish fed the rotifers enriched with all three Chlorella treatments. Swim bladder inflation was lowest in fish fed the rotifers enriched with Nannochloropsis. The proportion of EPA was higher in fish fed the rotifers enriched with Nannochloropsis, while that of DHA increased proportionally with the DHA levels in the rotifers enriched with Chlorella. These results suggest that rotifers enriched with Nannochloropsis (EPA-rich rotifers) are effective to enhance growth and survival, but DHA instead of EPA is essential to improve the swim bladder inflation in amberjack larvae.  相似文献   
84.
Process water of a pulp mill with extended kraft cooking, two-stage oxygen delignification, and chlorine dioxide bleaching was examined from the aspect of a new standard for environmental water quality in Japan. According to the new standard, the concentration of dioxins – polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans, coplanar polychlorinated biphenyls – in environmental water is restricted to less than 1pg TEQ/l. We clarified that the concentrations of the dioxins in sewers in the chlorine dioxide stage and the alkali stage were less than 1pg TEQ/l and that the 2,3,7,8-tetrachlorodibenzofuran concentrations were 0.5pg/l or less. In addition, a main source of 1,3,6,8- and 1,3,7,9-tetrachlorodibenzo-p-dioxins in the process water seemed to be an agrochemical in water supplied from a river.  相似文献   
85.
ABSTRACT:   The effect of taurine on growth of yellowtail juveniles Seriola quinqueradiata was investigated by a feeding experiment of diets containing various taurine levels. Test diets supplemented with 0, 0.5, 1.0, 1.5 and 2.0% of taurine were prepared. These diets were fed to yellowtail juveniles with an initial mean body weight of 0.5 g for 6 weeks. Supplementation of taurine in the diet of yellowtail improved their growth performance significantly ( P  < 0.05) over the initial 3-week period. The fish fed with the taurine-supplemented diet improved in percent gain and feed efficiency over both 3 and 6 weeks. Taurine content in the muscle proportionally increased with the dietary taurine level. The fish fed without supplemented taurine diet showed higher contents of serine in the muscle. With each increase in the inclusion level of taurine content in the diet, the concentration of serine in the muscle decreased. The cystathionine content in the muscle of each group was unchanged. These results suggest that taurine supplementation in the diet not only improves growth but also affects the sulfur amino acid metabolism of yellowtail juveniles.  相似文献   
86.
Objective— To develop and assess clinical outcomes for osteochondral autografting for treatment of stifle osteochondrosis (OC) in dogs. Study Design— Retrospective case series. Animals— Dogs with stifle OC (n=10). Methods— Osteochondral autografting was developed and optimized in canine cadavers and purpose‐bred research dogs using the Osteochondral Autograft Transfer System (OATS). Dogs with stifle OC (n=10 dogs, 12 stifles) were then treated using the OATS system. Outcomes were assessed by radiography (n=12), magnetic resonance imaging (1), second‐look arthroscopy (9), lameness scoring (12), and telephone survey of owners (10 clients, 12 stifles) 6–15 months after surgery. Results— Complications were documented in 4 of the 12 stifles treated and included peri‐incisional seromas (3) and marked stifle effusion (1). Subjective assessment of follow‐up radiographs revealed evidence of integration of the grafts with maintenance of subchondral bone surface architecture. Subjective assessment of follow‐up MRI in 1 stifle revealed evidence for incorporation of grafts with restoration of articular surface contour. Second‐look arthroscopy 6–30 weeks after surgery revealed maintenance of articular cartilage at the graft site. Dogs were significantly (P<.001) less lame at follow‐up compared with preoperative scores. Based on follow‐up owner surveys, only 2 dogs had no pain or lameness; the other dogs were judged to have mild pain and/or lameness. All owners noticed improvement in the dogs' quality of life after surgery. Conclusion— Osteochondral autografting deserves consideration and further evaluation as a primary treatment option for stifle OC in dogs. Clinical Relevance— Osteochondral autografting for treatment of lateral femoral condylar OC lesions in dogs using OATS instrumentation is safe and results in improved function and quality of life based on owners' perception 6–15 months after treatment.  相似文献   
87.
Dew was collected using several kinds of collectors at the same time, and the composition was compared. The volumes per unit surface areas of dew formed were different based on the types of collectors. It is found that the amounts of the ions, which in part come from gaseous substances, such as organic acids, nitrous acid, etc., per unit area in dew increase with dew volume per unit surface area. On the other hand, chloride, nitrate, sodium, potassium and magnesium which come from only particles showed no variation with the dew volume per unit surface area. These results suggest that the composition of dew varied by the dew volume per unit surface area formed in the different collectors. Dew is usually collected on a polytetrafluoroethylene (PTFE) sheet. The above result suggests that the dew concentration on the PTFE sheet does not represent the real dew concentration on various materials, such as leaves, cars, roofs, road, etc. To determine the real concentration of dew on a material, the material itself has to be usedas a collector. The PTFE sheet could be used as a standard dew sampler forcomparison of dew formed at various places.  相似文献   
88.
89.
Urinary liver-type fatty acid-binding protein (uL-FABP) is a clinically useful biomarker for monitoring chronic kidney disease (CKD) in humans. However, long-term monitoring of uL-FABP in CKD cats has not been reported. The objective of this preliminary study was to investigate whether the urinary excretion of L-FABP could predict the deterioration of renal function in 2 CKD model cats. Urinary liver-type fatty acid-binding protein (uL-FABP) increased before standard renal biomarkers, including serum creatinine, blood urea nitrogen, and symmetric dimethylarginine, in 1 cat with deteriorating renal function, but remained low and relatively stable in another cat with stable renal function. Our results suggest that uL-FABP is a potential clinical biomarker for predicting the progression of CKD in cats, as it is in humans.  相似文献   
90.
This study was conducted to evaluate the effects of supplementation of Wakame seaweed stalks on the immunity and intestinal microflora of pigs. Three separate experiments were performed: Relatively young (start at 20–30 kg; Experiments 1 and 2) and fattening period (70 kg; Experiment 3). All pigs (including the control group) were fed the same commercial feed, free from antibiotic additives, but in the feed for the treatment groups, 1% seaweed powder was added. There were no group differences observed in daily weight gain and feed intake in Experiments 1 and 2 between groups; however, daily weight gain was significantly higher in the treatment group compared to the control group in Experiment 3. The percentage of peripheral blood natural killer cells of the treatment group was significantly higher than that of the control group in all experiments. Although addition of seaweed changed the gene expression of cytokine and toll‐like receptors of the small intestinal Peyer's patches slightly, seaweed seems to alter intestinal microflora preferentially, for instance, there was an increase in Lactobacillus and a decrease of Escherichia coli observed. These results suggest that Wakame seaweed can be used as supplement for pig feed to improve the gut health and immunity of pigs.  相似文献   
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