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151.
为满足水果追溯条码清晰、耐久的要求,选取橘子为试验对象,对比纳秒激光和皮秒激光在其表面打印二维码的效果.试验结果表明:与纳秒激光相比,皮秒激光在橘子表皮上打印的线条平直度佳,轮廓清晰,对表皮的损伤更小. 相似文献
152.
不同类型有机物料的有机磷组成及生物有效性 总被引:2,自引:1,他引:1
[目的]研究不同有机物料的有机磷组成及其作为磷源施用后的供磷能力,为化肥磷的有机替代奠定理论基础.[方法]供试有机物料包括粪肥类(猪粪、羊粪)、绿肥类(豌豆、苜蓿和绿豆)、秸秆类(小麦秸秆、玉米秸秆和油菜秸秆).分析了8种有机物料的全磷、有机磷含量和C/P值,采用Bowman-Cole方法测定了有机磷中的活性(LOP)... 相似文献
153.
木粒--SPDA是我们根据木腐生性食用菌在自然状态下,均发生于树木上的特性,以及食用菌在营养需求上与其习性相关的原理,在SPDA基础上添加适量的木粒制成的一种母种培养基.在我们多年的使用中发现,用该培养基培养的母种生长势好,在转接原种时,适应能力强,萌发定植快;用作菌种保藏基质时,保藏时间长,且能很好保持菌种的优良性状. 相似文献
154.
AIM: To study cellular and molecular mechanism involved in increasing susceptibility of infection in psychological stress persons. METHODS: Comparative studies were performed with double staining and flow cytometry analysis on immunophenotyping and in vitro expression of early activating surface molecule CD69 in response to mitogens on T cells from peripheral blood of 20 healthy college student volunteers before and after psychological stress. A series of term final examinations was defined as psychological stress. RESULTS: Immunophenotyping analysis showed no statistically significant difference in the percentage of CD2, CD3, CD4, CD8, CD19, CD20, CD16 and CD56 positive lymphocyte populations before and after psychological stress. There was a statistically significant decrease in the in vitro expression of CD69 in response to polyclonal stimulators on the T cells from persons after psychological stress than those before psychological stress. The percentage of CD69 expression (CD69+CD3+/CD3+%) in response to PHA and PDB in the whole blood culture for 72 hours decreased respectively from 28.1±4.1 and 80.7±6.8 on the T cells obtained before psychological stress to 17.6±3.8 and 65.8±7.9 on those obtained after psychological stress, while there was no statistically significant difference between the CD69 expression rates without stimulators on the T cells obtained before and after psychological stress. CONCLUSIONS: The effects of psychological stress to immune system is not on the level of changing proportions of the sub-populations within peripheral blood lymphocytes. Psychological stress can decrease the activating response of T cells in healthy persons, which may be responsible for the increase of susceptibility to infection in the psychological stress persons. 相似文献
155.
AIM:To investigate the effect of berberine on IL-1 or tumour necrosis factor (TNF) induced polymorphonuclear leucocyte(PMN)-endothelium adhesion and adhesion molecules.METHODS:Based on the model of human umbilical vein endothelial cell (HUVEC), this study adopted Rose Bengal Stain, cell ELISA, immunocyto-chemical techniques to investigate the effect of berberine on PMN-endothelium adhesion and the expression of cell adhesion molecules (CAMs).RESULTS:Berberine inhibited IL-1, TNF-induced HUVEC adhesion for PMN when pretreated HUVEC and antagonised IL-1, TNF-induced upregulation of ICAM-1 on HUVEC. Meanwhile, TNF-stimulated PMN adhesion for HUVEC and CD18 upexpression on PMN was diminished in the presence of berberine.CONCLUSION: Inhibite PMN-endothelium adhesion by downregulating the CAMs expression to inhibite PMN migration across endothelium is one of the mechanisms of antiinflammation of berberine. 相似文献
156.
AIM:To explore the relationship between change of serum melatonin (MT) and pathogenesis of hepatic encephalopathy (HE). METHODS: Changes of MT level in sera of cirrhosic patients with HE and without HE were determined by ELISA, normal serum served as control. The change of serum MT level in exacerbation and remission in HE was also determined.RESULTS:MT level in patients with HE was higher than that withour HE (P<0.01). MT levels of both groups were higher than that of normal group (P<0.01). They were (308.53±59.07) ng/L, (139.85±34.59)ng/L,(77.73±28.41)ng/L, respectively. Serum MT level in exacerbation was higher than that in remission (P<0.01), they were (301.52±66.42)ng/L and (147.81±23.31) ng/L, respectively. CONCLUSION: The elevation of MT content in sera may be closely related to the onset of hepatic coma. 相似文献
157.
CHEN Yu-lu WANG Xin-yu ZHENG Shu-zhan DU Yan-fei YE Qiang LI Jia-fu FAN Zhong-cai LI Guang 《园艺学报》2000,36(8):1531-1536
AIM To observe the effect of recombinant mouse interleukin-11 (rmIL-11)injected subcutaneously into mice on heart structure and function and to determine its pro-fibrotic effect. METHODS C57BL/6 mice were randomly divided into experimental group and control group.The mice in experimental group were injected subcutaneously with recombinant mouse IL-11 at the dose of 100 μg·kg-1·d-1 for 3 consecutive weeks, while the control group were given equal volume of normal saline in the same way. After the experiment was finished, the parameters of heart function were measured by echocardiography.The heart weight was weighed and the cardiac weight index (CWI) was calculated. HE staining and Masson's trichrome staining were performed to observe the pathological changes and the extent of myocardial fibrosis in mouse myocardia respectively, and the cardiac collagen volume fraction (CVF) was calculated. The expression levels of extracellular matrix proteins in the myocardial tissues of mice, including type Ⅰ collagen, type Ⅲ collagen and fibronectin, were determined by Western blot. RESULTS Left ventricular ejection fraction and left ventricular fraction shortening in experimental group were obviously lower than those in control group (P <0.01), however left ventricular end-diastolic diamension and left ventricular end systolic dimension were significantly higher than those in control group (P <0.05).Compared with control group, the CWI was increased (P <0.01), the myocardial arrangement was disorder, the necrosis of cardiac myocytes was increased, and excessive deposition of collagen was observed in the myocardial tissues in experimental group. Correspondingly, the CVF and protein levels of type Ⅰ collagen, type Ⅲ collagen and fibronectin in the left ventricle in experimental group were increased significantly (P <0.05). CONCLUSION Injection of rmIL-11 into the mice subcutaneously induces fibrogenesis in the heart, which implies that IL-11 is likely a novel pro-fibrotic factor. 相似文献
158.
GUAN Cang-hai ZHAO Yu-qiao Guo Liang CHEN Yu-Zhu WANG Wei-Na JIANG Xing-ming 《园艺学报》2000,36(10):1908-1912
MNX1 antisense RNA 1 (MNX1-AS1) is a newly discovered long non-coding RNA (lncRNA), which is highly dysregulated in various carcinomas and its expression level is closely related to the overall survival and prognosis of patients. MNX1-AS1 regulates the occurrence and development of carcinomas by endogenous competitive adsorption of miRNA, regulating cell cycle, inducing epithelial mesenchymal transformation and activating multiple signaling pathways. The in-depth study of the carcinogenesis of MNX1-AS1 is useful for the early diagnosis, targeted therapy and prognostic assessment of relevant carcinomas. This article reviews the roles of MNX1-AS1 in malignant tumor. 相似文献
159.
全子叶生物活性豆腐凝胶特性的研究 总被引:1,自引:0,他引:1
通过因子筛选实验,确定了接种量、微生物转谷氨酰胺酶(MTG)用量和水豆比是影响全子叶生物活性豆腐凝胶特性的关键因子。在此基础上,采用响应曲面法(Response SurfaceMethodology,RSM)分别建立了豆腐硬度和持水率的二次多项数学模型,验证了模型的有效性并探讨了上述3个因子的交互作用。从产品成本和凝胶特性综合考虑,选择出最佳配比,即乳酸菌接种量为105cfu/mL,MTG用量为347 U/L,水豆比为8.5,其硬度和持水率实测值分别为44.8g和89.2%,可生产出富含乳酸菌和几乎全部大豆营养的健康豆腐。 相似文献
160.