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91.
A cachexic 2-year-old koi (Cyprinus carpio) presented with progressive distension of the coelom (1-month period) and anorexia of 2 days' duration. The fish had been maintaining a normal swimming position, although it was often observed low in the water column. Water quality was within normal limits. A skin scrape, fin clip, and gill clip were unremarkable. The respiration rate (opercular movement) was elevated at 100 breaths per minute. Blood chemistry values demonstrated a hypoalbuminemia (1.3 g/dL), elevated uric acid (1.3 mg/dL), elevated creatine kinase (>14,000 U/L), and hyperkalemia (3.9 mmol/L). Ultrasound revealed a fluid-filled coelom and a soft tissue mass containing large vessels filling most of the coelomic cavity. Fine-needle aspirates of the mass were nondiagnostic, though a poorly exfoliating mesenchymal tumor was suspected. The mass was surgically excised. Pathological examination of the mass revealed it to be a poorly demarcated and unencapsulated neoplasm forming 3 histological patterns in which a spindle cell stromal component predominated over an intermediate-sized blastema and much smaller tubular patterns. These features were most consistent with a nephroblastoma. The koi survived 5 days postoperatively but remained low in the water column and was found dead on day 6. A full necropsy of this patient was not performed.  相似文献   
92.
Nitrogen fertilization management under water limited conditions needs to be refined to save environmental ecosystems and increase economic returns. Two-year field studies in a split-plot design were conducted to investigate the response of maize to different nitrogen rates (N100 = 100, N130 = 130, and N160 = 160?kg N ha?1) under two irrigation levels (100 or 75% of water requirements). Under deficit irrigation, water and N were used more efficiently than normal water supply. N-fertilization of drip irrigated maize grown under deficit irrigation with N160 increased the uptake of N, P and K by 35, 29 and 70% compared with N100. Fertilization of maize grown under deficit irrigation with N160 increased the grain, straw and biological yield and water use efficiency by 50, 14, 22 and 33% compared with N100. Based on the obtained results, 160?kg of N ha?1 is the optimum rate of N for maize irrigated by 75% of water requirements.  相似文献   
93.
The basket cockle, Clinocardium nuttallii, is a candidate species for aquaculture in British Columbia, Canada. Previous research on broodstock conditioning, embryonic development and larval rearing of C. nuttallii demonstrated the potential for reliable hatchery production of cockle seed. In this paper, we investigated the effects of culture density (50% and 150% bottom cover in a monolayer) and substratum (none and fine sand) on cockle seed survival, growth, behaviour and shell morphology to improve the efficiency of the nursery production phase. Low stocking density (50% cover) yielded a shell length increase from 3 to 7 mm over a 4‐week period. High stocking density (150% cover) negatively impacted some of the growth and condition parameters studied, but did not have a statistically significant effect on seed survival. Growing seed without substratum did not significantly affect seed survival or growth, but led to shell deformities (at shell length >15 mm) and lower burrowing rates when cockles were subsequently placed on sand. We recommend planting seed for grow‐out at a shell length not exceeding 15 mm. Acclimating seed to the substratum before planting may increase the burrowing rates, thereby reducing the risks of seed dislocation and mortality. Additional studies are required to determine optimal substratum acclimation times and techniques.  相似文献   
94.
The chitin biosynthesis inhibitor diflubenzuron and its analog BAY SIR 8514 are equitoxic for eggs ofSpodoptera littoralis. BAY SIR 8514 residues on alfalfa fed toSpodoptera larvae were more toxic than diflubenzuron residues, whereas BAY SIR 8514 topically applied to these larvae was consistently twice as toxic as diflubenzuron, according to different criteria.  相似文献   
95.
OBJECTIVE: To investigate the effect of routine dental floating on weight gain, body condition score, feed digestibility, and fecal particle size in pregnant mares fed various diets. DESIGN: Randomized controlled clinical trial. ANIMALS: 56 pregnant mares. PROCEDURE: Mares were randomly allocated to 1 of 4 feed groups (n = 14 mares/group). All horses were sedated and an oral examination was performed, after which dental floating was performed on 7 horses in each group. Body weight was measured, and a body condition score was assigned before and at various times for 24 weeks after dental floating. Feed digestibility and fecal particle size were analyzed 7 and 19 weeks after dental floating. RESULTS: Weight gain, change in body condition score, feed digestibility, and fecal particle size were not significantly different between horses that underwent dental floating and untreated control horses. In contrast, weight gain was significantly associated with feed group. In the control horses, neither the number of dental lesions nor the presence of any particular type of lesion at the time of the initial oral examination was significantly associated with subsequent feed digestibility. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that dental floating does not result in significant short-term changes in body weight, body condition score, feed digestibility, or fecal particle size in healthy pregnant mares. Further studies are necessary to determine the clinical utility of regular dental floating in apparently healthy horses.  相似文献   
96.
OBJECTIVE: To determine whether occlusal angle of the premolar and molar teeth (ie, molar occlusal angle) was associated with feed digestibility, water balance, or fecal particle size in adult horses. DESIGN: Observational study. ANIMALS: 40 pregnant mares ranging from 3 to 19 years old. PROCEDURE: The horses were randomly allocated to 1 of 5 feeding groups with 8 horses/group. Horses were sedated, and molar occlusal angle was measured with 2 methods. An oral examination was performed, and total number of dental abnormalities was recorded. Feed digestibility, water balance, and fecal particle size were measured 7 and 16 weeks later. RESULTS: Molar occlusal angle ranged from 6.3 degrees to 19.3 degrees and was not significantly associated with feed digestibility, water balance, or fecal particle size. The number of dental abnormalities was not associated with feed digestibility. Molar occlusal angle did not vary significantly with horse age. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicate that molar occlusal angles between 6 degrees and 19 degrees do not adversely affect feed digestibility, water balance, or fecal particle size in adult horses. Additionally, there was no association between age and molar occlusal angle.  相似文献   
97.
The aims were (a) to quantify the number of Duddingtonia flagrans chlamydospores per gram of faeces (CPG) recovered from sheep administered with different oral doses and, (b) to describe the relationship between CPG and eggs per gram of faeces (EPG) on the efficacy to reduce Haemonchus contortus infective larvae. Three doses of chlamydospores per kg BW were orally administered during seven days: (T1) non treated control group, (T2) 1 × 106, (T3) 2.5 × 106 and (T4) 5 × 106. Three lambs, infected with H. contortus, were used per group. Faeces were obtained from the rectum of each lamb during the fungal administration period (days 0–6) and for six days after that period. Four coproculture replicates were made from each animal in days 2, 4, 6, 8 and 10. A higher chlamydospore dose produced higher CPG in faeces (p < 0.05), but a clear dose dependent effect was not found either in the larvae reduction or in the CPG:EPG ratio. When ratios were re-analyzed, independently of the treatment groups of origin, a better efficacy was obtained with a ratio from 5 to 10 CPG:EPG and a higher ratio (>10 per egg) showed a lower reduction efficacy (p < 0.05). The binomial analysis showed that for each unit of increment in CPG:EPG ratio there was a reduction of larvae number until a point (between 5 and 10 CPG:EPG) where no further reduction was detected. The surface response test indicated that the number of larvae was reduced by CPG until possible saturation. The highest CPG:EPG ratios did not necessarily improve efficacy of D. flagrans.  相似文献   
98.
99.
The aim of the study was to investigate the location of motor neuron somata of geniohyoid muscle in rat. Nine Sprague‐Dawley rats were used in this study. Operations were performed under general anaesthesia. Nembutal sodium, 40 mg per kg intraperitoneally was used for anaesthesia. 0.02 to 0.05 ml of 30% horseradish peroxidase (Sigma Type VI) solution in normal saline was injected into the exposed right geniohyoid muscle. After 48 hr, the animals were fixed by perfusion through left ventricle of heart, first by 100 ml normal saline and then with 500 ml of 1.25% glutaraldehyde and 1% paraformaldehyde in 0.1 M phosphate buffer, pH 7.4, at room temperature, and finally with 500 ml of 10% sucrose in the same buffer at 4°C. The medulla oblongata and first cervical segment of spinal cord were removed, kept in 10% sucrose in above phosphate buffer at 4°C for 24 hr. Thereafter, their serial transverse sections were cut in a cryostat at a thickness of 60 μm. The sections were treated according to tetramethyl benzidine (TMB)‐horseradish peroxidase (HRP) method. HRP‐labelled neuron somata were observed at the following sites: (a) In ventral part of right main hypoglossal nucleus in upper two‐thirds of the closed part of medulla oblongata. (b) In ventrolateral subnucleus of hypoglossal nucleus in lower third of closed part of medulla oblongata. (c) At spinomedullary junction, they were located in dorsomedial part of right ventral grey column; a few were also seen here scattered on right side of central canal and among corticospinal fibres.  相似文献   
100.
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