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161.
Objective— To describe surgical correction of pes varus deformity in Dachshunds by acute medial opening wedge osteotomy of the distal aspect of the tibia stabilized with a hybrid external skeletal fixator (HESF), and report clinical and radiographic outcomes.
Study Design— Multicenter, retrospective clinical study.
Animals— Immature Dachshunds (n=13) with pes varus deformity.
Methods— Limb function and lameness scores were assigned before and after surgery, and correction was determined visually at surgery. Tibiotarsal joint orientation (TTJO) and medial and lateral tibial cortex lengths, measured on radiographs of deformed and normal (when available) limbs, were compared before correction and after fixator removal.
Results— Pes varus deformities (n=14) were corrected; 93% had good to excellent clinical outcome. None of the dogs had a normal preoperative gait. Mean TTJO of abnormal and normal tibiae before surgery were 29° varus (median, 28°), and 12° valgus (median, 12°). Angular correction ranged from 20° to 51° (mean, 36±8°; median, 36°). M e an TTJO after fixator removal was 7° valgus (median, 7°). Two dogs had minor transient postoperative complications whereas 3 had major complications; only 1 of which was resolved.
Conclusions— Pes varus deformity in Dachshunds can be corrected by acute medial opening wedge osteotomy of the distal aspect of the tibia stabilized by HESF. Technique modifications are needed to improve correction precision.
Clinical Relevance— Visual inspection of limb alignment during surgery resulted in good to excellent clinical outcomes; however, 91% of tibiae were under- or overcorrected (mean, 6°; median, 5°). Limb alignment should be based on evaluation of immediate postoperative TTJO measurements, not solely on intraoperative visual assessment.  相似文献   
162.
163.
Sablefish (Anoplopoma fimbria) were reared in 1.6 × 2.0 × 1.2 m deep net-pens for 36 months using low-cost, locally available diets (frozen salmon and herring). Post-capture mortality, wound repair, and adaptability to floating net-pens were investigated. Results showed no mortality directly related to capture and rapid healing of wounds resulting from capture. All fish adapted to captivity without apparent difficulty.For grow-out trials, 36 age 1+ fish were tagged for individual identification. Male and female fish were identified using an immunodiffusion technique. Net-pen adaptability studies tested three diets. Maximum observed mean weight gains were 0.10 kg per fish per month. After 2 years, there was no significant difference in growth (length or weight) between any of the diets. A different weight gain was recorded between male and female fish fed the salmon diet.  相似文献   
164.
Experiments at two sites growing winter wheat show that in order to manage a wheat canopy more effectively, the use of specific remote sensing techniques both to monitor crop canopy expansion, and to determine variable nitrogen applications at key timings is required. Variations in seed rate were used to achieve a range of initial crop structures, and treatments were compared to standard farm practice. In the first year, the effect of varying seed rate (250, 350 and 450 seeds m−2) on crop structure, yield components and grain yield, was compared to the effects of underlying spatial variation. Plant populations increased up to the highest rate, but shoot and ear populations peaked at 350 seeds m−2. Compensation through an increased number of grains per ear and thousand grain weight resulted in the highest yield and gross margin at the lowest seed rate. In later experiments, the range of seed rates was extended to include 150 seeds m−2, each sown in 24 m wide strips split into 12 m wide halves. One half received a standard nitrogen dose of 200 kg [N] ha−1, the other a variable treatment based on near ‘real-time’ maps of crop growth. Both were split into three applications, targeted at mid-late tillering (early March), growth stages GS30-31 (mid April) and GS33 (mid May). At each timing, calibrated aerial digital photography was used to assess crop growth in terms of shoot population at tillering, and canopy green area index at GS30-31 and GS33. These were compared to current agronomic guidelines. Application rates were then varied below or above the planned amount where growth was above- or below-target, respectively. In the first field, total nitrogen doses in the variable treatments ranged from 188 to 243 kg [N] ha−1, which gave higher yields than the standards at all seed rates in the range 0·36–0·78 t ha−1 and gross margins of £17 to £60 ha−1. In the second field, variable treatments ranged from 135 to 197 kg [N] ha−1 that resulted in lower yields of −0·32 to +0·30 t ha−1. However, in three out of the four seed rates, variable treatments produced higher gross margins than the standard, which ranged from £2 to £20 ha−1. In both fields, the greatest benefits were obtained where the total amount of applied nitrogen was similar to the standard, but was applied variably rather than uniformly along the strips. Simple nitrogen balance calculations have shown that variable application of nitrogen can have an overall effect on reducing the nitrogen surplus by one-third.  相似文献   
165.
We compared two assessments of the status of gopher tortoise populations at 10 protected sites in Florida, taken about a decade apart. We assessed status indirectly, using surveys of burrows along belt transects. Transect placement and timing were identical between surveys. We compared numbers of burrows, relative numbers of burrows of different activity conditions, and size distributions of burrows between surveys. The comparisons indicated that populations had declined at as many as eight of the sites. We found no strong connection between population decline and decline in habitat quality, as reflected in decreased ground cover and/or increased canopy cover between surveys. The response of a population to decline in habitat quality may depend on initial habitat structure, the degree of change in habitat structure, the period of time over which change is measured, the amount of habitat involved, and the level of habitat management.  相似文献   
166.
Lead aerosols in the atmosphere: increasing concentrations   总被引:2,自引:0,他引:2  
The concentrations of atmospheric lead around San Diego, California, have been determined and their geographic and seasonal variations are explained. The lead aerosol concentration at San Diego is increasing at a rate of 5 percent per year. The isotopic composition of lead aerosols is similar to that of the lead additives isolated from gasoline, which are the largest contributors to atmospheric lead pollution.  相似文献   
167.
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