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981.
Tetracapsuloides bryosalmonae is the myxozoan parasite that causes the commercially important proliferative kidney disease (PKD) in salmonid aquaculture. Previous studies on the binding of lectins to T. bryosalmonae identified Griffonia simplificola agglutinin I (GS I) as useful for parasite identification. This lectin was also implicated as recognizing antigenic structures on the parasite. Here, we examine the histochemical staining and ultrastructural localization of a panel of 21 lectins on the extrasporogonic stage of T. bryosalmonae. The histochemical staining studies indicated that the majority of lectins bound to the renal stages of T. bryosalmonae, however not all of these lectins could be successfully localized using immunogold electron microscopy. Of the lectins that were localized many, including GS I, bound to membranes associated with the lysosomal pathway within the extrasporogonic primary cell of the parasite, indicating that these organelles are rich in glycoconjugates. The histochemical staining of Erythrina cristagalli ECL was unique and highlighted a different distribution of glycoconjugates in the periphery of some extrasporogonic parasites within the renal sinuses when compared with stages in the interstitium, suggesting the presence of distinct blood forms of T. bryosalmonae.  相似文献   
982.
Our knowledge of the biology of fish gametes is still limited. Up to now research was short-term, aiming at solving practical questions connected with gamete storage and artificial insemination. More information on gamete biology is now available and has been summarized in this minireview.In vivo storage of gametes in the genital tract after ovulation or spermiation may be influenced by the osmotic environmentvia changes in the ionic composition of the companion fluid. There is great inter-individual variability in gamete survival bothin vivo andin vitro. Mechanisms involved in the initiation of trout sperm motility have been analysed; after dilution in water or NaCl solution (125 mM) at pH > 7, Ca++ entry due to changes in membrane potential have been observed. The involvement of cAMP and protein phosphorylation has been reported. The morphological, physical and biochemical changes in eggs that have been studied after fertilization and the corticol reaction lead to a better understanding of the mechanisms of polyspermy blockage.  相似文献   
983.
The simultaneous presence of monodon baculovirus (MBV) and white spot syndrome virus (WSSV) in apparently healthy postlarvae of Penaeus monodon from different hatcheries in India was studied by nested polymerase chain reaction (PCR). MBV could be detected in 54% of the samples. However, only 15% of samples were positive by non-nested reaction. WSSV could be detected in 75% of samples, 19% being positive by non-nested reaction. The results show simultaneous presence of WSSV and MBV in many samples at various degrees of infection. Only 14% of the samples analysed were negative for both viruses.  相似文献   
984.
985.
986.
木质素磺酸钠合成水性环氧固化剂的研究   总被引:2,自引:2,他引:0  
通过曼尼希反应,用木质素磺酸钠改性脂肪族多胺,合成了一种新型的水性环氧固化剂,红外光谱表征了目标产物的结构.通过测试固化体系的邵氏硬度、拉剪强度、正拉黏接强度和耐热性等,研究了NaOH水溶液用量、原料的配比、反应温度、反应时间、固化剂与环氧树脂的配比等对固化体系性能的影响.结果表明:在不使用NaOH水溶液情况下,木质素...  相似文献   
987.
Zhou W  Di LQ  Shan JJ  Bi XL  Chen LT  Wang LC  Cai BC 《Fitoterapia》2011,82(8):1222-1230
Shuang–Huang–Lian (SHL), a traditional Chinese formula containing Lonicerae japonicae flos (LJF), Scutellariae radix (SR) and Forsythiae fructus (FF), is commonly used to treat acute upper respiratory tract infection, acute bronchitis and light pneumonia. Forsythoside A is one of the main active ingredients in Forsythiae fructus, a key herb in SHL. In the present study, effects of different compositions in SHL on the in vitro metabolism in Sprague–Dawley rat liver microsomes of forsythoside A were investigated. The observations from Sprague–Dawley rat liver microsomes in the presence of β-NADPH or UDPGA that forsythoside A may be the substrates of CYP3A4, CYP2C9, CYP1A2, UGT1A6, UGT1A3, UGT1A1 and UGT1A9; Chlorogenic acid may be the substrates of CYP3A4, CYP2C9, CYP1A2, CYP2C19, UGT1A6, UGT1A3 and UGT1A1; Baicalin may be the substrates of CYP3A4, CYP2C19, CYP1A2, UGT1A9, UGT1A1 and UGT1A3; Baicalein may be the substrates of CYP3A4, CYP2E1 and UGT1A6. It was also found that the residue of forsythoside A in SHL, FF + LJF and FF + SR was greatly increased compared with that in FF in Sprague–Dawley rat liver microsomes in the presence of β-NADPH or UDPGA, which indicated that the metabolism of forsythoside A in SHL may be influenced by chlorogenic acid in LJF acting on the CYP3A4, CYP2C9, CYP1A2, UGT1A6, UGT1A3 and UGT1A1; baicalin in SR acting on the CYP3A4, CYP1A2, UGT1A9, UGT1A1 and UGT1A3; baicalein acting on the CYP3A4 and UGT1A6 respectively.  相似文献   
988.
989.
FMD clinically positive 250 tissue samples (mouth and hoof epithelium and vesicle swabs, tongue tissue) and 175 secretion samples (milk, saliva, serum, plasma) were evaluated by RT-PCR for the diagnosis of FMD with different pair of universal and serotype-specific primers from 2006 to 2007 in Punjab, Pakistan. Universal primer pair P1/P2 from VP1 gene detected FMD in 182 out of 250 (72.8%) tissues and 92 out of 175 (52.6%) secretion samples, while universal primer 1F/1R from 5′UTR region detected FMD in 218 out of 250 (87.2%) tissues and 142 out of 175 (81.1%) secretion samples. 1F/1R proved better than the P1/P2 primer pair for primary diagnosis of FMD, direct from the clinical positive samples. Direct sequencing of the universal primer pair P1/P2 revealed that O serotype of FMD was circulating in this region. O serotype of FMD was detected with O-1C(ARS4)/PNK 61, AU(O)/AU(rev), AU(O)/PNK61 primer pairs, these primer pairs also compared with each other. AU(O)/AU(rev) and AU(O)/PNK61 detected O serotype of FMD in 88.9% tissue and swab (mouth and hoof vesicle swabs) samples and 71.9% different secretion (milk, saliva, serum, plasma) samples, while O-1C(ARS4)/PNK 61 detected 48.1% tissue and swab (mouth and hoof vesicle swabs) samples and 37.5% different secretion (milk, saliva, serum, plasma) samples. AU(O)/AU(rev), AU(O)/PNK61 primer pairs detected 40.8% more tissue and swab samples, while these pairs detected 34.4% more secretion samples. Cloning of PCR product of AU(O)/AU(rev) VP1 gene and sequencing for phylogenetic studies revealed that O serotype of FMD circulating in Punjab, Pakistan was genetically very diverse from the ‘O’ serotype in Middle East and Europe. The dendrogram showed that Pakistan ‘O’ serotype was very much similar genetically to its neighbor countries (Sri Lanka, India, Iran, Iraq, and China) and PanAsia 1 lineage which caused 2001-outbreak in UK and 1994-outbreak in Saudi Arabia, etc.  相似文献   
990.
桑枝多糖对正常小鼠免疫功能的影响   总被引:3,自引:0,他引:3  
将桑枝整体干燥粉碎后提取并精制多糖。给正常小鼠灌胃不同剂量的桑枝多糖,通过对小鼠胸腺指数、脾脏指数、腹腔巨噬细胞吞噬率及吞噬指数、淋巴细胞转化率、血清溶血素含量、溶血空斑形成数量等生化指标的检测,研究桑枝多糖对正常小鼠的免疫调节作用。结果表明:桑枝多糖能显著提高正常小鼠的胸腺指数、脾脏指数、腹腔巨噬细胞吞噬鸡红细胞的吞噬率与吞噬指数,高剂量组(600 mg/kg)小鼠的胸腺指数和脾脏指数的提高幅度达显著水平(P<0.05),低剂量(200mg/kg)组、中剂量(400 mg/kg)组、高剂量组小鼠腹腔巨噬细胞的吞噬率与吞噬指数的提高幅度均达极显著水平(P<0.01);桑枝多糖还可显著促进小鼠淋巴细胞的转化以及血清溶血素和溶血空斑的形成,中剂量组、高剂量组小鼠的淋巴细胞转化率提高幅度均达极显著水平(P<0.01),中剂量组小鼠的血清溶血素含量和溶血空斑数量的提高幅度均达显著水平(P<0.05),高剂量组小鼠的血清溶血素含量和溶血空斑数量的提高幅度均达极显著水平(P<0.01)。研究结果显示,桑枝多糖对正常小鼠具有较好的免疫增强作用。  相似文献   
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