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21.
This report describes the successful surgical repair of a transverse, displaced scapula fracture in a foal. A 3.5 mm locking compression plate (LCP) was used on either side of the spine of the scapula. The suprascapular nerve was apparent upon dissection as it passed directly over the fracture line and care was taken to leave it intact, although the fracture line itself caused some irritation. The foal recovered without long‐term nerve damage and is sound at 1.5 years post surgery.  相似文献   
22.
A general linear model (GLM) was used to standardize catch per unit effort (CPUE) data for Alaska walleye pollock (Theragra chalcogramma) from the Bering Sea fleet for the years 1995–1999. Data were stratified temporally by year and season and spatially by area using either Alaska Department of Fish and Game (ADF&G) or National Marine Fisheries Service (NMFS) reporting areas. Four factors were used: vessel identification (ID) number, vessel speed, percentage of pollock by weight in the haul (a measure of targeting), and whether most of the haul took place before or after sunset. At least 29 combinations of main effects, quadratic covariates, and interactions were tested for each year/area/season stratum. GLM models explained from 31 to 48% of the total sums of squares. Vessel identification number was included in all models and explained the most variability. Of the remaining factors, the square of the percentage of pollock in the haul was included in most models, following an F-test to determine parsimony. Analysis of the vessel identification number coefficients indicated that larger vessels tended to have higher CPUEs; and that this relationship differed between dedicated catcher vessels and offshore catcher processors. Coefficient estimates and response surfaces generally indicated increased CPUEs with the percentage of pollock in the haul and showed mixed results with vessel speed. The vessel identification number incorporated most vessel characteristics, leaving vessel speed primarily as a fitting variable with less biological meaning. The year/area/season stratification procedure was found to be necessary due to the unbalanced design, which otherwise would have factor levels with no data in a large combined model. In addition, the stratification procedure reduced the variability in CPUE substantially.  相似文献   
23.
The aim of this study is to derive an equation that has the ability to model live weight of Irish dairy cows over lactation. The data set consisted of 6899 cows from 63 herds, of which 428 were from experimental herds and 6471 cows were from commercial herds. An initial examination focussed on time series techniques, as the data are of a time series nature. Splines were also examined to determine the dimensions of a model required to represent the data. As an incomplete gamma function, which was previously used to model milk yield, has been used in other studies to model live weight, various milk yield models were investigated. Finally, live weight changes between two calvings were modelled as a function of age, days in milk and pregnancy. As multicollinearity was evident in this function, the variance inflation factor was examined and principal component analysis was carried out on the variables responsible for multicollinearity. The proposed live weight model has a better fit than previous models, weak multicollinearity and the residuals are homoskedastic, independent and normally distributed. This live weight model therefore provides an acceptable level of accuracy in representing the shape of the live weight curve for Irish dairy cows and can be easily modified for different environmental scenarios.  相似文献   
24.
OBJECTIVE: To identify factors affecting radial alignment after oblique corrective osteotomy stabilized with a type II external fixator and to evaluate the results of this treatment for antebrachial growth deformities. STUDY DESIGN: Retrospective study SAMPLE POPULATION: Twenty-eight dogs with unilateral antebrachial growth deformities treated with acute corrective osteotomy stabilized with a type II external fixator. METHODS: Medical records and preoperative and postoperative radiographs of the affected and contralateral limb were reviewed. Cause of deformity, age, weight, and gender were recorded. Radial length, varus/valgus angulation, and cranial/caudal angulation were measured from radiographs of the treated and contralateral limbs. Preoperative and postoperative angulation and length discrepancy were compared between affected and contralateral limbs. RESULTS: Correction of varus/valgus angle discrepancy was achieved by using acute corrective osteotomy stabilized with type II external skeletal fixation. No significant change was noted for correction of cranial/caudal angle discrepancy or length discrepancy between the affected and control limb. CLINICAL RELEVANCE: Varus/valgus angle deformities can be treated successfully with type III external fixation after oblique corrective osteotomy. Patients with significant length or cranial/caudal angle discrepancies or both that negatively impact function may require the use of hinged circular fixators or other dynamic techniques to achieve adequate correction.  相似文献   
25.
AIM: To determine the effect of increasing molybdenum (Mo) intakes on serum and liver copper (Cu) concentrations and growth rates of grazing red deer (Cervus elaphus). METHODS: Molybdenum- and Cu-amended fertilisers were applied to six 1.1-ha paddocks in a 3 x 2 design. Three levels of Mo were applied on two paddocks at each level in mid April (designated Day 1); levels were: none (control), 0.5 (medium) and 1.0 (high) kg Mo/ha as sodium molybdate. In late May (Day 39), two levels of Cu (none and 3.0 kg Cu/ha, as copper sulphate) were applied to each of the three levels of Mo-treated paddocks. Pasture Mo, Cu and sulphur (S) concentrations were measured at about fortnightly intervals. In late June (Day 74), ten 6-month-old red deer hinds were placed on the six experimental pastures, and serum and liver Cu concentrations were monitored at about monthly intervals for 102 days. The hinds were weighed on four occasions during the trial. RESULTS: Mean pasture Mo concentrations on Day 56 were 2, 4.6 and 11.3 mg/kg dry matter (DM) for the untreated control, medium and high Mo-treated pastures, respectively. Pasture Cu concentration was 95 mg/kg DM on Day 59, 53 mg/kg DM on Day 90, and 9 mg/kg DM by Day 153. Mean S concentration in pasture was 3.3 (range 3.03-3.45) g/kg DM. Copper application to pasture had no significant effect on serum and liver Cu concentrations in deer so data were pooled within Mo treatment. Mean initial (Day 74) serum Cu concentration was 9.2 micromol/L. In the deer grazing the control Mo pasture, this increased to 10.3 micromol/L on Day 112, before decreasing to 6.4 micromol/L on Day 176. In deer grazing the medium and high Mo-treated pastures, mean serum Cu concentrations were 3.8 and 3.9 micromol/L, respectively, on Day 112, and 2.5 and 3.3 micromol/L, respectively, on Day 176. Mean initial (Day 74) liver Cu concentration was 131 micromol/kg fresh tissue. In the deer grazing the control Mo pasture, this declined to 120 and 52 micromol/kg on Days 112 and Day 176, respectively. In deer grazing the medium and high Mo-treated pastures, liver Cu concentrations decreased to 55 and 52 micromol/kg fresh tissue, respectively, on Day 112, and 21 and 20 micromol/kg fresh tissue, respectively, on Day 176. Mean serum and liver Cu concentrations were not significantly different between deer grazing the medium and high Mo-treated pastures, and were lower (serum p=0.003, liver p<0.001) in those groups than in deer grazing the untreated control pastures. No clinical signs of Cu deficiency associated with lameness were observed. Deer grazing pastures that had Mo concentrations >10 mg/kg DM had lower (p=0.002) growth rates (100 vs 130 g/day) than those on pastures containing <2.4 mg Mo/kg DM. CONCLUSION: Increasing pasture Mo concentrations from 2 mg/kg DM to > or =4.6 mg/kg DM significantly reduced serum and liver Cu concentrations in grazing deer. Reduced growth rate was observed at pasture Mo concentrations >10 mg/kg DM.  相似文献   
26.
REASONS FOR PERFORMING STUDY: There are few reports of case series of horses with supernumerary cheek teeth (SCT) that document clinical findings, treatment and long-term outcome. OBJECTIVES: To review the clinical and ancillary diagnostic findings and responses to different treatments in horses with SCT. METHODS: The case records of 15 horses were reviewed and long-term outcomes obtained by telephone interview. RESULTS: Fifteen horses with a total of 24 SCT were identified. Two SCT were incidental findings and were not treated. Clinical signs were improved or resolved in 11 of 13 of the teeth treated conservatively and all 6 treated by extraction had a favourable outcome. Four horses were subjected to euthanasia within a short period of diagnosis, either due to a poor prognosis at the outset or failure to respond to initial conservative treatment. CONCLUSIONS: Some SCT are chance findings and do not cause clinical signs. In those instances where clinical signs of dental disease are mild, conservative treatment including the management of diastema and reduction of overgrowths is often effective. Horses with severe clinical signs attributable to an SCT are likely to require extraction of the offending tooth. POTENTIAL RELEVANCE: An SCT is an uncommon dental anomaly but should be considered in the differential diagnosis of cases with signs of severe dental disease. The preferred management for SCT is very variable and determined by the severity of the associated changes, but ranges from conservative measures through forceps extraction per os to major facial flap surgery.  相似文献   
27.
Procedures for the diagnosis of Br. ovis infection in rams were evaluated by examining 10 rams artificially infected by preputial inoculation. Observations were undertaken at weekly intervals for 1 year to follow changes in clinical, bacteriological and serological findings. Clinical lesions were detected in 1 ram 3 weeks after inoculation and in all rams by 8 weeks; lesions were undetectable in 3 rams at the completion of the trial. The presence of inflammatory cells in semen samples was the earliest indication of infection being demonstrated in 2 rams at 2 weeks and in all rams by 8 weeks; subsequently 86% of samples were positive. Br. ovis was detected in semen smears from 3 rams at 4 weeks but only once in all rams (at 27 weeks); overall 52% of semen smears were positive from 4 weeks onwards. Br. ovis was cultured from semen of 5 rams after 4 weeks and from all rams at 5 weeks; thereafter 97% of samples were positive. All rams developed significant titres to the CFT between 2 and 9 weeks; thereafter the CFT was a reliable indication of infection in 6 rams, highly suggestive in 3 and unreliable in one. By 8–10 weeks all rams developed significant titres to the IHA which were then maintained in all rams for the remainder of the trial.  相似文献   
28.
Understanding how organisms respond to landscape heterogeneity is foundational to landscape ecology. We characterized seasonal scales of movement of white-tailed deer (Odocoileus viginianus) in an agricultural–forest matrix using first-passage time analysis (FPT) for 62 GPS-collared individuals. We investigated whether those scales were driven by demographic or landscape features. We found FPT for each individual across all seasons was typically dominated by a peak in variance of FPT/area at scales (radii) from 425 to 1,675 m. These peaks occurred at scales consistent with seasonal space use. We observed additional lower magnitude peaks at larger scales (3,000–6,000 m) and small scales (25–150 m). Peaks at larger scales were associated with seasonal migrations and dispersal events. Small scale peaks may represent resting or foraging behavior. Female movements were organized at smaller scales than males in the spring/summer season. Models relating landscape features to movement scales suggest that deer perceive and move within the landscape differently as the roles of dominant land-cover types shift seasonally. During winter, configuration (interspersion/juxtaposition) of land-cover types is more important to deer than during spring/summer and fall. During spring/summer and fall, movement behavior may be dictated by reproductive and harvest activities.  相似文献   
29.
AIM: To determine the effect of increasing molybdenum (Mo) intakes on serum and liver copper (Cu) concentrations and growth rates of grazing red deer (Cervus elaphus).

METHODS: Molybdenum- and Cu-amended fertilisers were applied to six 1.1-ha paddocks in a 3 × 2 design. Three levels of Mo were applied on two paddocks at each level in mid April (designated Day 1); levels were: none (control), 0.5 (medium) and 1.0 (high) kg Mo/ha as sodium molybdate. In late May (Day 39), two levels of Cu (none and 3.0 kg Cu/ha, as copper sulphate) were applied to each of the three levels of Mo-treated paddocks. Pasture Mo, Cu and sulphur (S) concentrations were measured at about fortnightly intervals. In late June (Day 74), ten 6-month-old red deer hinds were placed on the six experimental pastures, and serum and liver Cu concentrations were monitored at about monthly intervals for 102 days. The hinds were weighed on four occasions during the trial.

RESULTS: Mean pasture Mo concentrations on Day 56 were 2, 4.6 and 11.3 mg/kg dry matter (DM) for the untreated control, medium and high Mo-treated pastures, respectively. Pasture Cu concentration was 95 mg/kg DM on Day 59, 53 mg/kg DM on Day 90, and 9 mg/kg DM by Day 153. Mean S concentration in pasture was 3.3 (range 3.03–3.45) g/kg DM. Copper application to pasture had no significant effect on serum and liver Cu concentrations in deer so data were pooled within Mo treatment. Mean initial (Day 74) serum Cu concentration was 9.2 µmol/L. In the deer grazing the control Mo pasture, this increased to 10.3 µmol/L on Day 112, before decreasing to 6.4 µmol/L on Day 176. In deer grazing the medium and high Mo-treated pastures, mean serum Cu concentrations were 3.8 and 3.9 µmol/L, respectively, on Day 112, and 2.5 and 3.3 µmol/L, respectively, on Day 176. Mean initial (Day 74) liver Cu concentration was 131 µmol/kg fresh tissue. In the deer grazing the control Mo pasture, this declined to 120 and 52 µmol/kg on Days 112 and Day 176, respectively. In deer grazing the medium and high Motreated pastures, liver Cu concentrations decreased to 55 and 52 µmol/kg fresh tissue, respectively, on Day 112, and 21 and 20 µmol/kg fresh tissue, respectively, on Day 176. Mean serum and liver Cu concentrations were not significantly different between deer grazing the medium and high Mo-treated pastures, and were lower (serum p=0.003, liver p<0.001) in those groups than in deer grazing the untreated control pastures. No clinical signs of Cu deficiency associated with lameness were observed. Deer grazing pastures that had Mo concentrations >10 mg/kg DM had lower (p=0.002) growth rates (100 vs 130 g/day) than those on pastures containing <2.4 mg Mo/kg DM.

CONCLUSION: Increasing pasture Mo concentrations from 2 mg/kg DM to ≥4.6 mg/kg DM significantly reduced serum and liver Cu concentrations in grazing deer. Reduced growth rate was observed at pasture Mo concentrations >10 mg/kg DM.  相似文献   
30.
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