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941.
针对中国对虾养殖产业遭受病害重创的情况,为解决基层相关技术人员短缺以及病害诊断准确率低的问题,结合神经网络专家系统在疾病诊断领域的应用,采用ASP.NET技术和B/S三层架构思想,设计并建立了基于BP神经网络的对虾病害诊断与防治专家系统。该系统是虾蟹养殖专家系统中的一个子系统,有效地解决了传统专家系统获取知识困难、自学习能力差和推理能力弱等问题,实现了对虾养殖的咨询、病害诊断与防治等功能,界面友好,操作简单实用,维护方便,具有一定的现实意义和推广价值。  相似文献   
942.
This study describes the synthesis of D-lactic acid from rice by fermentation using microorganisms. Some micro-organisms were found to be active for producing D-lactic acid of high optical purity after an intensive screening test for D-lactic acid bacteria using glucose as substrate. Rice powder was hydrolyzed with a combination of enzymes:α-amylase,β-amylase, and pullulanase, and the resultant rice saccharificate was subjected to the fermentation with the selected D-lactic acid bacteria. After the optimization of this fermentation it has been confirmed that D-lactic acid can be manufactured in a pilot scale.  相似文献   
943.
A three-dimensional, porous collagen/chitosan complex sponge was prepared to closely simulate basic extracellular matrix (ECM) constitutes, collagen and glycosaminoglycan. The complex sponge was prepared by a lyophilization method and had the regular network with highly porous structure, suitable for cell adhesion and growth. The pores were well interconnected, and their distribution was fairly homogeneous. The complex sponge was crosslinked using 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide (EDC) and N-hydroxysuccinimide (NHS) to increase its biological stability and enhance its mechanical properties. The crosslinking medium had a great effect on the inner structure of the sponge. The homogeneous, porous structure of the sponge was remarkably collapsed in an aqueous crosslinking medium. However, the morphology of the sponge remained almost intact in a water/ethanol mixture crosslinking milieu. Mechanical properties of the collagen/chitosan sponge were significantly enhanced by EDC-mediated crosslinking. The potential of the sponge as a scaffold for tissue engineering was investigated using a Chinese hamster ovary cell (CHO-K1) line.  相似文献   
944.
OBJECTIVE: To determine outcome in dogs and cats that underwent extensive (ie, > 50%) resection of the small intestine and identify factors associated with outcome. DESIGN: Retrospective case series. ANIMALS: 13 dogs and 7 cats. PROCEDURE: Medical records were reviewed, and follow-up information was obtained. RESULTS: In all 7 cats and in 8 of the 13 dogs, extensive intestinal resection was performed because of a foreign body. Mean+/-SD estimated percentage of intestine that was removed was 68+/-14% (range, 50% to 90%). Two dogs were euthanized 3 days after surgery because of dehiscence of the surgical site and development of septic peritonitis; 1 dog died of acute respiratory distress syndrome 5 days after surgery. The remaining 10 dogs and 7 cats were discharged from the hospital, and follow-up information was available for 15 of the 17. Median survival time was 828 days, and 12 of the 15 animals for which long-term follow-up information was available had good outcomes. However, none of the factors examined, including percentage of intestine resected, were significantly associated with outcome. CONCLUSIONS AND CLINICAL RELEVANCE: Most dogs and cats that underwent extensive resection of the small intestine had a good outcome. The amount of intestine resected was not associated with outcome. These data may be useful in providing prognostic information in cases of extensive small intestinal resection.  相似文献   
945.
946.
为了探索桑园种草养鸡模式对土壤化学质量变化的影响,本研究通过分析种草养鸡3年桑园土壤养分含量的变化,探索桑园种草养鸡模式对土壤质量的影响。结果表明,受鸡群生理代谢的作用和影响,桑园种草养鸡后,增加了土壤中N、P、K和Mg元素的含量,桑园土壤存在着酸化的趋势,种草养鸡模式加速了桑园土壤的钙素退化。  相似文献   
947.
研究魔芋飞粉、淀粉与聚乙烯醇(PVA)共混的膜制备条件和膜性能。以魔芋飞粉、淀粉、PVA为主要原料,以甘油为增塑剂,通过流延成膜法制备魔芋飞粉/淀粉共混薄膜,以耐水性和力学性能优化飞粉/淀粉/的配比、PVA的浓度、用量,并从共混膜的相容性和热稳定性角度进行表征来研究共混机理。共混膜的最佳飞粉/淀粉配比为1∶3,PVA最佳用量为6%50 m L每5克飞粉/淀粉,此时吸水倍数为0.78 g/g,穿刺力为100.85 N。PVA用量越大,膜耐水性和机械强度越大,但相容性越差;飞粉的添加量越大耐水性稍有下降,但机械强度明显上升。共混膜全反射红外光谱中出现3 700~3 000 cm-1的峰变窄、2 927.7、2 850.4、1 574.6和1 545.5 cm~(-1)出现强烈的尖锐峰、1 400~800 cm~(-1)处峰强减弱,可能葡甘聚糖与淀粉大分子间形成物理键合作用;飞粉淀粉共混膜的横截面微形貌呈现均匀的网络结构,全淀粉或全飞粉出现分层和断层的不均一现象。飞粉与淀粉有较好的相容性,添加适量PVA共混后可制备耐水性和机械性能良好的共混膜。  相似文献   
948.
949.
Lyme disease (LD) is a common tick‐borne disease in New Hampshire (NH). While LD is a reportable condition and cases are counted for public health surveillance, many more people receive care for tick bites or diagnoses of LD than are reflected in surveillance data. NH's emergency department (ED) data system was queried for tick bite and LD‐related encounters. Chief complaint text was queried for words related to LD or tick bites. International Classification of Diseases 9th Revision (ICD‐9) codes were queried for the LD diagnosis code (088.81). Emergency department patient data were matched to reportable disease data to determine the proportion of ED patients reported to the health department as a suspected LD case. Data were analysed to calculate frequencies for key demographic and reporting characteristics. From 2010 to 2014, 13,615 tick bite or LD‐related ED encounters were identified in NH, with most due to tick bites (76%). Of 3,256 patients with a LD‐related ED encounter, 738 (23%) were reported to the health department as a suspected LD case. The geographic distribution of ED patients was similar to reported LD cases; however, the regions of the state that experienced higher rates of ED encounters were different than the regions that observed higher rates of reported LD cases. Seasonal distribution of ED encounters peaked earlier than reported LD cases with a second peak in the fall. While age and sex distribution was similar among ED patients and reported LD cases, the rates for children 5 years and younger and adults 65 years and older were greater for ED encounters. Patients frequently visit the ED to seek care for tick bites and suspected LD. Results of ED data analyses can be used to target education, in particular for ED providers and the public through timely distribution of evidence‐based educational materials and training programmes.  相似文献   
950.

Background

Current methods available for assessing alterations in lung mechanics require sophisticated equipment and are of limited availability. A method that could assess lung area change with respiration might be a clinically useful surrogate for assessing lung compliance.

Objective

To use fluoroscopy to determine percent change in thoracic and lung areas in healthy dogs.

Animals

Forty‐four client‐owned dogs with no evidence of respiratory disease.

Methods

Prospective study. Resting respiration was recorded fluoroscopically, and peak inspiratory and expiratory frames were captured for 3 typical respiratory cycles. The number of intrathoracic pixels in the entire thoracic cavity was measured for both inspiration and expiration, and the average percent change in intrathoracic area was determined for each dog. This process was repeated by a hemithorax measurement of lung area that excluded the mediastinum and cardiac silhouette. Proposed reference ranges (and 95% confidence intervals [CI]) were computed by a nonparametric percentile distribution.

Results

Median percent change in thoracic dimension for the total thorax measurement was 12.5% (CI, 8.9–24.0%). Median percent change for the hemithorax measurement was significantly (P < 0.001) larger (20.8%, CI, 14.3–37.6%). Both measurement techniques were correlated with body weight but not with age, sex, thoracic conformation, body condition score (BCS), or breed.

Conclusions and Clinical Importance

Fluoroscopy allows a noninvasive and repeatable measure of lung area changes during respiration that must be corrected for body weight. Additional studies in dogs with respiratory diseases are needed to determine its utility in detecting clinically useful alterations in lung area changes.  相似文献   
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