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We investigated the possibility to reduce the usage of Blasin®Flowable (BF), a disinfectant inhibiting the germination and appressorium formation of Pyricularia oryzae Cavara conidia, by using carbon dioxide microbubbles (CO2MB). Germination was significantly inhibited by 10 000-fold diluted BF solution containing CO2MB generated by the decompression-type generator compared to CO2 millibubbles (CO2MMB) and CO2MB generated by the gas-water circulating-type generator. Appressorium formation in the 10 000-fold diluted BF solution containing both CO2MBs was less than that in CO2MMB. Scanning electron microscopy showed wrinkles and dents on the surface of conidia treated with 5 000-fold diluted BF solution containing both CO2MBs. Via transmission electron microscopy, we observed the expansion of the vacuole and the intracellular space and bloated or absent lipid granules in the conidia treated with BF solution containing both CO2MBs. Our results show that inhibition of the conidium germination and appressorium formation of P. oryzae Cavara by 10 000-fold diluted BF solution could be achieved by using the decompression-type CO2MB.  相似文献   
2.
Contrast-enhanced ultrasound was used to study focal and multifocal lesions of the spleen in 26 dogs and two cats affected by 11 benign and 18 malignant splenic diseases. A second-generation microbubble contrast medium (Sonovue) was injected into the cephalic vein and enhancement patterns were subjectively described and time intensity curves calculated. Final diagnosis was obtained by histopathologic examination after splenectomy (n=19) or by needle aspiration and sonographic follow-up after 4 and 8 weeks (n=9). Contrast-enhanced ultrasound parameters, improving the characterization between benign and malignant lesions, were established. The most useful criterion was the hypoechogenicity of the lesion in the wash-out phase combined with the presence of tortuous feeding vessels, which was observed in association with malignancy. All malignant lesions were hypoechoic to the surrounding spleen 30s after starting the contrast medium injection. Lymphosarcoma and hemangiosarcoma had characteristic perfusion patterns. Lymphosarcoma had rapid time to peak and early wash-out phase with a honeycomb pattern during the wash-out. Hemangiosarcomas were large nonperfused masses in all phases surrounded by hypervascular splenic parenchyma. Benign lesions except one hematoma and a benign histiocytoma had the same perfusion pattern as the surrounding spleen. Ultrasonographic and contrast-enhanced ultrasound findings of an accessory spleen are reported. Contrast-enhanced ultrasound can improve the characterization of focal or multifocal lesions of the spleen.  相似文献   
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Modern ultrasound contrast media are gas-containing stabilized microbubbles that remain intact in the circulating blood for several minutes after intravenous injection and increase the intensity of the backscattered ultrasound. When the microbubbles disappear from the blood, they can be detected in the parenchyma of the liver and the spleen for about 30 more minutes (late liver- and spleen-specific phase). The insonated microbubbles produce second harmonic ultrasound frequencies, whose detection requires nonconventional ultrasound modalities such as pulsed inversion imaging. Nonconventional ultrasound techniques can also be used without microbubbles because second harmonics can be generated by ultrasound in tissues as well. The physical principles and advantages of nonconventional ultrasound techniques are described. The circulating microbubbles can be used not only to enhance weak Doppler signals, but also to perform dynamic contrast studies. Contrast-enhanced dynamic ultrasound studies--similar to contrast-enhanced CT and MRI examinations--have been used in humans to characterize lesions noninvasively (i.e., without biopsies) found during conventional ultrasound examinations. To map the distribution of contrast medium in a nodule or in an organ, specific scanning techniques such as stimulated acoustic emission have been developed. Stimulated acoustic emission occurs when high acoustic pressure ultrasonic waves disrupt the stationary or slowly moving microbubbles. This results in the release of a large amount of harmonic ultrasound frequencies. When the stimulated acoustic emission technique is used for dynamic studies, scanning must be interrupted several times to allow the microvasculature of the lesion to refill with microbubbles (interval delay imaging). The contrast patterns of malignant and benign hepatic nodules in humans have been the most intensively studied. Another type of dynamic study in humans measures the transit time of the contrast medium; that is, how fast the peripherally injected microbubbles reach the hepatic veins. Hepatic cirrhosis can be differentiated from other diffuse parenchymal liver diseases by a shorter transit time. Introducing nonconventional ultrasound techniques and ultrasound contrast media in veterinary diagnostic imaging may have potential value; however, intensive research should be carried out before ultrasound contrast agents can routinely be used in clinical practice.  相似文献   
4.
气源及活性剂对曝气滴灌带水气单双向传输均匀性的影响   总被引:2,自引:2,他引:0  
曝气滴灌过程中水、氧、气传输均匀性是评价曝气灌溉质量的重要指标。活性剂的添加和传输方式的优选对曝气滴灌传输过程中微气泡的存在和溶解氧的保持有重要意义。为提高水气耦合物在滴灌过程中传输的距离和均匀性,该文采用Mazzei 1078文丘里空气射流器进行曝气增氧,以空气和氧气为供试气源,研究活性剂BS1000浓度(0、1、2和4 mg/L)和传输方式(单向和双向)对曝气滴灌下水、氧、气传输特性的影响。结果表明:曝气导致单向传输下流量均匀性略有下降,但可显著提高灌溉水中溶解氧和掺气比例;随着活性剂浓度的增加,掺气比例显著增加(P0.05);活性剂的添加促进了氧气曝气下溶解氧的增加;溶氧均匀性和流量均匀性随着活性剂浓度的增加无显著性变化,但单向传输下4 mg/L BS1000的出气均匀性较未添加活性剂显著降低;双向传输的流量均匀性、溶氧均匀性和出气均匀性分别在95%、96%和67%以上,较单向传输分别平均提高14.00%、4.05%和30.64%(P0.05),是曝气滴灌长程管道传输推荐的布置方式。研究结果为曝气滴灌过程中灌溉技术参数优化和管道的科学布置提供理论依据。  相似文献   
5.
综述了微泡技术在分离、提取和降解有机物甲基叔丁基醚、多环芳烃、多氯联苯、活性淤泥、石油光泽几个方面的应用,与传统方法相比,微泡技术使甲基叔丁醚的利用率提高15倍;使多环芳烃和多氯联苯的去除时间缩短;使活性淤泥中较大固体减少缩短消除时间,并且增加能源生产;使含有有机酸的水溶液浊度从200NTU降低到2NTU,并且和表面光泽完全隔离。展望了微泡技术在色素或某类有机物的分离和提取中的应用,为色素或某类有机物的分离和提取提供更进一步的研究参考。  相似文献   
6.
Four dogs with an accessory spleen are described. The accessory spleens appeared as a round‐to‐triangular structure located in the perisplenic area. They were homogeneous and isoechoic with the adjacent spleen. Contrast‐enhanced ultrasound was performed using a second generation microbubble contrast medium (sulfur hexafluoride). The type and timing of enhancement of the accessory spleen was similar to that of the parent spleen. Contrast‐enhanced ultrasound is a noninvasive modality useful in distinguishing an accessory spleen from a mass of another origin.  相似文献   
7.
目的 探讨门静脉注射超声微泡对肝脏增强型绿色荧光蛋白(EGFP)质粒表达的影响.方法 48只健康SPF级雄性SD大鼠随机分为3组,每组16只.A组经尾静脉注射EGFP裸质粒,B、C组分别经尾静脉和门静脉导管注射微泡与EGFP质粒混悬液,同时按设定参数和时间超声辐照肝区.转染后第1、3、7、11天每组随机处死4只大鼠,肝...  相似文献   
8.
与传统增氧机械相比,超微泡增氧装置具有增氧效率高、噪音小、便于维修保养等特点,但同时也存在辅助结构多、安装调试不便、价格较高等缺陷,从而影响该装置的应用推广.在深入研究超微泡增氧装置的基础上,提出改进方案,设计一套改进型超微泡增氧装置实验室模型.改进型超微泡增氧装置正常开机运行22 min,实验水体溶氧量达到饱和,计算得到微气泡的直径范围是10~120 μm,平均直径为40 μm左右,标准增氧能力为1.908 kg(O2)/h,氧吸收率为36%,动力效率为3.469 kg(O2)/h,增氧效率较高.通过改进,可省去1台自吸泵、1个射流器和1只能量释放器,在达到同样增氧效果前提下,简化了装置,降低成本约50%左右,运行平稳可靠.改进方案可行,便于应用推广.  相似文献   
9.
AIM: To investigate the effect of gene transfection of FKBP12.6 (FK12.6 binding protein) on the canine failing heart induced by rapid ventricular pacing. METHODS: Three weeks after onset of rapid ventricular pacing (250 bpm), 28 canines were divided into 4 groups. Either pcDNA3.1-FKBP12.6 plasmid encoding human FKBP12.6 gene (transfection groupⅠ,Ⅱ; observed at the 4th or 14th days respectively after transfection) or empty vector (controlⅠ,Ⅱ) was transferred into myocardium under ultrasonic microbubble destruction. After transfection, maintenance pacing at a reduced rate (190 beats/min) was continued until end-point of experiment. Echocadiographic, hemodynamic and plasmic ANP (atrial natriuretic peptide), BNP (brain natriuretic peptide) data were collected three times (before pacing, before transfection and endpoint). Semiquantative RT-PCR was used to identify FKBP12.6 expression in myocardium. RESULTS: Gene transfection of FKBP12.6 elevated expression of FKBP12.6 mRNA 3.5 folds at day 4, and 1.7 folds at day 14 respectively, compared with control group. Significant improvements of cardiac function, hemodynamics and plasmic concentrations of ANP, BNP were observed in transfection groupⅠ and these effects were stable for at least 2 weeks. Cardiac output (CO), ejection fraction (EF) and fractional shortening (FS) were still lower than pre-pacing although they increased in transfection groups. Left ventricular end-diastolic diameter (LVEDD) and left ventricular end-diastolic volume (LVEDV) decreased at day 14 but LVEDD remained unchanged at day 4 compared with pre-transfection. CONCLUSION: Gene transfection of FKBP12.6 improves cardiac functions in the failing heart and reverses myocyte remodeling. This might be a novel therapeutic application for treating human heart failure.  相似文献   
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