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41.
The effect of a high and low non-starch polysaccharide diet (HNSP and LNSP diet) and ultrasound treatment on particle size distribution and carbon bioavailability in fecal waste of rainbow trout (Oncorynchus mykiss) was studied. Feces were collected from four flow-through fish tanks, two tanks fed the HNSP diet and two the LNSP diet. The collected feces were sonicated (disintegrated) in duplicate with high-intensity (0.6 W/ml), low-frequency (f = 20 Hz) ultrasound at five different energy levels (0.6 W/ml for 0, 0.25, 1, 4, and 16 min). The particle size distribution of the treated feces samples was measured by wet sieving (1000, 500, 200, 100, 63, 36, 1.2 μm screen size) and total suspended solids (TSS) measurement. Carbon bioavailability in sonicated fecal waste samples was determined with oxygen uptake rate (OUR) tests. The results showed that: (1) feces from the HNSP diet contained significant more particulate material and bigger particles; (2) carbon bioavailability was almost three times higher in untreated LNSP feces when compared with HNSP feces; (3) almost 50% of HNSP feces could have been recovered on a microscreen of 36 μm after wet sieving, whereas it was only 10% for LNSP feces; (4) the production of small particles (1.2–36 μm), which could pass a drum filter screen and potentially accumulate in RAS, was approximately 50 g/kg feed, showing no significant differences between diets; (5) sonication increased fecal dry matter below 36 μm (p = 0.015), but it had no significant effect on the median particle size; (6) sonication increased carbon bioavailability with 7–10% for the HNSP feces (p = 0.037); (7) fecal particles withstood up to 16 min sonication at an intensity of 0.6 W/ml and a frequency of 20 Hz corresponding to specific energy input of 20,000 kJ/kg DM without major changes in particle size distribution. The results of this study indicate that the applied ultrasound treatment of fecal waste is not an effective method to increase short-term carbon bioavailability.  相似文献   
42.
Doppler ultrasound is an emerging technology that has the potential to increase the diagnostic, monitoring, and predictive capabilities of equine theriogenologists and researchers. The technology is based on Doppler-shift frequencies, wherein the ultrasound frequency of echoes from moving red cells is increased or decreased as the cells move toward or away from the transducer. In spectral mode, the blood flow in a specific vessel can be assessed by placing a sample-gate cursor on the image of the lumen of the vessel. In addition, an angle cursor can be used to represent the angle of intersection of the ultrasound beams with the direction of blood flow (Doppler angle). The Doppler-shift frequency and the Doppler angle are used by the instrument for computing blood velocity. The focused results from placement of a sample gate in an artery are displayed by a spectrum that represents the changing velocities over time in association with the pulses of cardiac cycles. Peak systolic, end diastolic, and time-averaged maximum velocities are computed and shown for a selected cardiac cycle. Doppler indices (resistance index, RI; pulsatility index, PI) are ratios that are computed from various points on the spectrum. The indices are relatable to the hemodynamics of the tissue supplied by the artery. Increasing RI or PI values indicate increasing resistance and decreasing perfusion of the distal tissues. In color-flow mode, Doppler-shift frequencies are obtained from areas delineated by the operator on the B-mode image and are transformed and expressed as color-coded spots representing areas of blood flow. Vascular perfusion of a structure can be quantitated by the number of colored pixels in an image or can be estimated subjectively by the extent of the colored spots. The Doppler technology has the potential for providing information on the status and future success of a structure. However, realization of the expected potential will depend on future experience and research.  相似文献   
43.
Anechoic, spherical cystic lesions are important findings on ultrasound examination. In polycystic renal disease of cats, they may be the only ultrasonographic sign of disease. This study assesses the accuracy of ultrasound, as used in a veterinary setting, for the detection of cysts. Using a spherical lesion ultrasound imaging phantom and 7.5- to 8-MHz linear array transducers, images of cysts of 2- and 4-mm diameter were created at various imaging depths from 0 to 6 cm. These were digitized and given to a panel of readers for interpretation. Area under receiver operating characteristic curves were used to evaluate test accuracy. It was shown that test accuracy was different at different imaging depths and differed with machines of differing price category. It is suggested that when setting standards for quality control in ultrasound, criteria used might be better related to imaging outcome studies rather than to aspects of machine specification.  相似文献   
44.
超声提取桦褐孔菌子实体多糖及多糖对癌细胞作用的研究   总被引:1,自引:0,他引:1  
采用正交试验优化桦褐孔菌子实体多糖的超声提取工艺条件,并对提取多糖的抗肿瘤活性进行研究。结果表明,桦褐孔菌多糖超声提取的最佳工艺条件为超声时间70min,温度80℃,频率20kHz,加水量12倍水,其多糖在体外对肝癌HEPG2细胞株具有明显的抑制作用,并可诱导肿瘤细胞凋亡,体内实验发现多糖可显著抑制小鼠S180肉瘤的生长,并具有增强免疫作用。  相似文献   
45.
Real-time ultrasonography was used to assist percutaneous renal biopsies in seven normal horses. Ultrasound (US) guidance and blind biopsy following US localization were compared. Ten biopsies (seven right kidney and three left kidney) were performed. A transverse approach to the lateral border of the right kidney through the 17th intercostal space was favored, with the needle angle being approximately perpendicular to the body wall. Both biopsy techniques were effective, but blind biopsy following US localization was favored as it was easily performed by one operator without the need for specialized biopsy equipment. The spleen had a variable location and its penetration with the biopsy needle was necessary to obtain two left kidney biopsies. Macroscopic and microscopic hematuria was observed postbiopsy in one and four horses, respectively, out of six horses examined. Perirenal hemorrhage was a prominent finding on necropsy in five of six horses euthanized.  相似文献   
46.
黄利华  刘欣 《安徽农业科学》2014,(17):5634-5637
[目的]为更好地利用马蹄加工皮渣中的资源,优化马蹄皮渣中总黄酮的微波提取工艺,得到得率较高的黄酮类化合物。[方法]采用Box-Behnken中心组合响应面法优化马蹄粉加工皮渣中总黄酮的微波提取工艺,建立了不同影响因素与马蹄总黄酮得率之间的函数关系。[结果]确定最佳提取工艺条件为:乙醇浓度55.4%,料液比1:30g/ml,微波功率320W,微波3min,在此条件下重复提取2次,理论得率为2.376%,经过验证得到总黄酮得率为2.365%,实测值与理论预测值之间的相对误差为0.461%。[结论]研究结果表明,优化得到的提取工艺可靠,可为马蹄加工废弃物的综合高效利用提供参考依据。  相似文献   
47.
48.

Background

Lipogranulomatous lymphangitis is inflammation of the intestinal lymphatic vessels and surrounding tissues caused by chronic leakage of lipid‐laden chyle. Grossly, lipogranulomas are typically disseminated small masses on the serosa and surrounding lymphatic vessels and consist of epithelioid macrophages, multinucleated giant cells, and cholesterol. Lipogranulomatous lymphangitis is occasionally seen in patients with lymphangiectasia and protein‐losing enteropathy (PLE).

Objectives

To characterize the historical features, clinical signs, treatment, histopathology, and outcome of dogs with focal lipogranulomatous lymphangitis.

Animals

Six dogs with ultrasonographic evidence of focal, regional small intestinal masses, often with involvement of the adjacent mesentery, and a diagnosis of focal lipogranulomatous lymphangitis based on histopathology of biopsied masses.

Results

The median age of dogs was 6.9 years (range 3–10 years). All dogs had total protein, globulin, and albumin concentrations within the reference range at initial presentation and had intestinal masses identified on abdominal ultrasound examination. Histopathologic evaluation of lesions identified severe mural and mesenteric lipogranulomatous lymphangitis. Lymphangiectasia was noted in 5 cases and only in sections within the mass‐like lesion; tissue without lipogranulomas had minimal lymphangiectasia, suggesting a localized phenomenon. Postoperative outcomes ranged from remission of clinical signs with no subsequent treatment for 10–12 months in 2 dogs, postoperative management with medical and nutritional management in 3 dogs, and no outcome for 1 case.

Conclusions and Clinical Importance

This case series describes a unique mass‐like manifestation of intestinal lipogranulomatous lymphangitis and should be considered as a possible differential diagnosis in dogs with an intestinal mass.  相似文献   
49.
超声波辅助提取紫甘蓝天然色素及其稳定性研究   总被引:3,自引:0,他引:3  
[目的]探讨超声波辅助提取紫甘蓝色素的新方法以及色素的稳定性。[方法]采取超声波辅助提取紫甘蓝色素的单因素试验和正交试验,确定最佳工艺条件,并研究色素的稳定性。[结果]结果表明,提取的最佳工艺条件为:超声辅助功率80%,浸提时间50 min,浸提温度为40℃,蒸馏水为浸提剂,液固比为40∶1(ml∶g)。紫甘蓝色素对光的稳定性较好;在室温下亦很稳定,温度升高其降解速度加快;对酸、碱和热稳定性较差;食品添加剂蔗糖和柠檬酸对其稳定性影响较小;Vc和苯甲酸钠影响较大;耐氧化性较好,耐还原性稍差;K+、Na+、Cu2+、Mg2+、Zn2+和Ca2+等离子对色素基本无影响,Fe3+、Al3+和Sn2+等对其稳定性有一定的影响。[结论]该方法提取色素缩短了提取时间,更有效、更经济。  相似文献   
50.
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