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991.
Robert W. Kramer DVM G. Sylvester Price DVM Gary J. Spodnick DVM 《Veterinary radiology & ultrasound》1994,35(2):132-136
Hypothyroidism was diagnosed in a dog which had undergone unilateral thyroid lobectomy and external beam irradiation (48 Gy in 3 Gy fractions) for a functional cystic thyroid adenocarcinoma. Hypothyroidism became biochemically apparent within 4 months of completion of radiation therapy, and clinically apparent within 7 months. Clinical signs resolved after thyroid hormone supplementation. The potential for alterations in thyroid function should be considered in any animal undergoing radiation therapy in which the thyroid gland is included in the radiation field. This potential may be greater if surgery and radiation are combined. 相似文献
992.
Philip D. Doblik William J. Hornof Timothy R. O'Brien 《Veterinary radiology & ultrasound》1980,21(5):224-232
Two rare earth radiographic intensifying screen-film systems were compared with a calcium tungstate screen-film systems in a series of clinically oriented trials. The calcium tungstate screen-film system was subjectively judged to have the highest overall image quality, primarily because of its wide latitude. Several rare earth screen-film combinations produced radiographs of excellent diagnostic quality. In general, image quality was inversely related to screen-film speed, whereas radiation protection was directly related to screen-film speed. Medium-speed rare earth screen-film combinations resulted in reductios of scatter radiation on the order of 30 to 70 percent compared with the par-speed film combination. Recommendations are made regarding the use of specific rare earth intensifying screen-film combinations in small and large animal diagnostic radiography. 相似文献
993.
嘉兴平原桑园土壤分类及肥力的调查 总被引:1,自引:0,他引:1
选择浙北嘉兴平原桑园代表性土壤,进行调查,研究其成因、分类及特性,并对高低产桑园土壤的理化性状进行化验分析,明确了嘉兴平原桑园土壤是历史上由人工堆迭而成,在分类系统上归属于潮湿土纲、正常潮湿土亚纲、潮土土类、暗潮土亚类、堆迭土土属,又分为粘质堆迭土、壤质堆迭土、粉质堆迭土3个土种。在统计众多土壤理化性状数据的基础上,暂拟本区高产桑园土壤16项理化性状,作为本地区桑园地力建设的参考。 相似文献
994.
贵州足球场草坪主要病虫害发生及防治 总被引:4,自引:0,他引:4
1998~ 1999年对贵州省足球场草坪病虫害进行了调查研究 ,其主要病虫害有 :锈病、禾草云斑病、褐斑病、禾生腐霉病、粘虫 ,麦二叉蚜等。并阐述了病虫害发生规律及防治技术 ,旨在为足球场草坪病虫害的防治提供参考 相似文献
995.
Oat cultivars (n = 22) varying in origin were examined in laboratory and field tests at Svalöv and Ultuna, Sweden, in 1985 and 1986. Comparisons were made between drought resistance characteristics of juvenile plants and drought responses in yield of crops grown in field. By using automatic, movable rain shelters in combination with drip irrigation systems, both high and low irrigation regimes could be effected in the field experiments.
Black oat cultivars were more stable under water deficiency conditions, particularly on sandy soil. They possessed the highest drought resistance indices both in the laboratory and field. Modern white oat cultivars were found to be most drought sensitive.
Drought resistance index (DRI) and seminal root length (RL), as assessed in seedling stage, were strongly correlated with field drought susceptibility index (S). It is suggested that DRI and RL could be used as selection criteria to increase drought resistance of oats. 相似文献
Black oat cultivars were more stable under water deficiency conditions, particularly on sandy soil. They possessed the highest drought resistance indices both in the laboratory and field. Modern white oat cultivars were found to be most drought sensitive.
Drought resistance index (DRI) and seminal root length (RL), as assessed in seedling stage, were strongly correlated with field drought susceptibility index (S). It is suggested that DRI and RL could be used as selection criteria to increase drought resistance of oats. 相似文献
996.
田间作业能否采用机械化进行,主要取决于机械化作业所产生的综合经济效益.若产出大于投入,则该项田间作业使用机械化有利,否则就不宜采用机械化.本文介绍了量化机械化作业经济效益的数学模型及它在农业生产中的实际应用. 相似文献
997.
998.
N. Ackerman DVM C. P. Spencer DVM D.A. Hager DVM P.W. Poulos Jr DVM PhD 《Veterinary radiology & ultrasound》1988,29(5):198-201
All personnel present in the X-ray examination room during equine radiography were monitored using low energy direct reading ionization chambers (pockets dosimeters) worn outside the lead apron at neck level. The individuals' task and dosimeter readings were recorded after each examination. Average doses ranged from 0 to 6 mrad per study. The greatest exposures were associated with radiography of the shoulder and averaged less than 4 mrad. The individual extending the horse's limb was at greatest risk although the individual holding the horse's halter and the one making the X-ray exposure received similar exposures.
A survey of the overhead tube assembly used for some of the X-ray examinations also was performed. Meter readings obtained indicated an asymetric dose distribution around the tube assembly, with the highest dose occurring on the side to which the exposure cord was attached.
Although the exposures observed were within acceptable limits for occupational workers, we have altered our protocol and no longer radiograph the equine shoulder unless the horse is anesthetized. Continued use of the pocket dosimeters and maintenance of a case record of radiation exposure appears to make the technologists more aware of radiation hazards. 相似文献
A survey of the overhead tube assembly used for some of the X-ray examinations also was performed. Meter readings obtained indicated an asymetric dose distribution around the tube assembly, with the highest dose occurring on the side to which the exposure cord was attached.
Although the exposures observed were within acceptable limits for occupational workers, we have altered our protocol and no longer radiograph the equine shoulder unless the horse is anesthetized. Continued use of the pocket dosimeters and maintenance of a case record of radiation exposure appears to make the technologists more aware of radiation hazards. 相似文献
999.
Cinosulfuron is a sulfonylurea herbicide largely used in the extensive cultures of flooded rice in North Italy. The degradation of cinosulfuron has been investigated in sterile aqueous solutions at 30 degrees C at different pH values. It was rapidly degraded at acidic pH (half-lives 3, 9 and 43 days at pH 4, 5 and 6, respectively) while the half-life was > 1 year at pH 7 and 9. Two degradation products formed by cleavage of the sulfonylurea bridge were identified by LC-MS. Degradation by selected mixed microbial cultures tested in aerobic and anaerobic conditions was very slow and attributable to chemical hydrolysis due to the acidic pH of the cultural broths. Degradation took place in freshly collected rice field water treated for two years with cinosulfuron but, in this case also, chemical hydrolysis prevailed over microbial degradation. In contrast, in flooded sediment simulating the paddy field environment, the dissipation rate of cinosulfuron was higher than expected from chemical hydrolysis according to the pH of the system, indicating the involvement of soil microflora. Although the herbicide exhibited a reduced affinity for the sediment surfaces demonstrated by the low value of the K(f) Freundlich coefficient (0.87 on a micromolar basis), the rapid dissipation observed in the simulated paddy field should prevent its leaching to ground water. 相似文献
1000.
A.D.?IwaroEmail author J.-M.?Thévenin D.R.?Butler A.B.?Eskes 《European journal of plant pathology / European Foundation for Plant Pathology》2005,113(2):173-182
The detached pod test by spray method (DPT-SM) was developed to facilitate the screening of cacao genotypes for resistance
to Phytophthora pod rot (PPR) caused by Phytophthora palmivora. The test has been adopted in many cacao research institutes, and it is imperative that its validity be assessed. In this
study, 40 genotypes from various cacao groups were selected and screened for resistance to PPR by DPT-SM and field observations.
Significant variation was observed in the reactions of the selected accessions based on the disease rating scale for DPT-SM
and the percentage pod rot from field observations. A correlation coefficient of 0.68 (P<0.001) was observed between the results of year-1 and year-2 field observations. However, relatively lower correlation values
were obtained between year-3 and year-1 (r=0.32; P=0.041) and year-3 and year-2 (r=0.35; P=0.025) field observations. A higher level of susceptibility was observed in the third year of field observations (63%) than
in the first (15%) and second (25%) years. This suggests that the predisposing factors for PPR were unstable between the years
of field observations. Data obtained from the Trinidad and Tobago Meteorological Services showed that the rainfall in November
of the third year was higher than the amounts of rainfall in November of the first 2 years of field observations. This month
marks the beginning of the main pod harvest season (November–February) and the high rainfall in November of the third year,
and the presence of large number of mature pods may account in part for the increase in PPR in the third year of field observations
than in the first 2 years. This shows that absolute reliance could not be placed on a single year of field observations in
determining clonal resistance to PPR. A correlation coefficient of 0.59 (P<0.001) was obtained between the result of year-2 field observations and DPT-SM. Relatively lower correlation values were
observed between DPT-SM and year-1 (r=0.55; P<0.001) and year-3 (r=0.44; P=0.005) field observations. The result of DPT-SM, however, shows a higher correlation (r=0.66; P<0.001) with the average of years 1–3 field observations. This suggests that a stronger association may exist between the
result of DPT-SM and the cumulative data on field observations for a period longer than 3 years. The correlation (r=0.66; P<0.001) observed in this study confirms the usefulness of DPT-SM as an effective method of assessing clonal resistance to
PPR and predicting field reaction in the long term. Since field observations are labour intensive and expensive to conduct
on a yearly basis, the DPT-SM offers a cheaper and effective means of assessing clonal resistance to PPR. Being a non-destructive
inoculation method, the DPT-SM provides a suitable option for cacao collections in genebanks to be assessed. It is also a
cost-effective method for use in cacao breeding programmes. Based on its reliability, the DPT-SM has been adopted in the CFC/ICCO/IPGRI
cocoa project ‘Cocoa Germplasm Utilization and Conservation: A Global Approach’ for the assessment of cacao resistance to
PPR in several cocoa producing countries. 相似文献