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1.
Progenies derived from crosses between Solarium tuberosum and 2n pollen-Producing diploid hybrids, exhibit obvious hybrid vigor. The 2n pollen-producing clone can act as a bridge in crossing S. tuberosum and S. andigena with S. phureja. Populations from 4x-2x crosses show more unifomity and less segregation compared with that of 4x-4x crosses. The parent-offspring correlation for the traits, starch content and tuber number, is significant at 0.01 level. The regrssion equations are Y (mp-F1)=1.0 1.2x and Y (mp - F1) = 5.3 0.8x, respectively. The 2n pollen-producing clones play an impotant role in increasing tuber stach content. Estimates of the combining ability for the main yield components indicate that additive effect prodominatcs for such trais as plot yield, tuber weight per plant and starch content, whereas both additive and non-additive effects lay equal stress on mean tuber weight and non-additive effect is important for tuber number. In general, non-additive effect appears to be important in  相似文献   
2.
姜片虫虫体抗原氨基酸的测定   总被引:1,自引:0,他引:1  
本文报道4种方法制备姜片虫虫体抗原,进行氨基酸组成的测定。其氨基酸总量(mg/100ml)结果显示:Ag-F1:608.50;Ag-F2:645.80;Ag-F3:357.14;Ag-F4:501.40;以 Ag-F3总量为最低,但值得重视的是 Ag-F3的丙氨酸(8.34),组氨酸(8.60),甘氨酸(11.00);苏氨酸(12.00),均显著降低。而 Ag-F4的组氨酸(4.80)为17种氨基酸含量最低者。其原因有待探讨。  相似文献   
3.
4.
AIM: To probe into the genetic susceptibility of HLA-DRB1 alleles to esophageal neoplasm in Hubei Han Chinese. METHODS: HLA-DRB1 gene polymorphism in 42 patients with esophageal neoplasm and 136 normal control subjects was studied by PCR and sequence. RESULTS: Allele frequency of HLA-DRB1 *0901 allele was significantly higher in esophageal cancer patients than those in normal controls(0.2500 vs 0.1397, P =0.028; the odds ratiO2.053; etiologic fraction 0.1282).There were no association between the rested HLA-DRB1 alleles with patients. CONCLUSION: Individuals carrying HLA-DRB1 *0901 may be susceptible to esophagealo carcinoma, its nucleotide sepuence approachs to the corresponded allele sequence(exoN2)published in GenBank.  相似文献   
5.
Genotyping of bovine leucocyte antigen DRB3.2 (BoLA-DRB3.2) in a total of 523 Norwegian Red (NR) cows from two groups selected for high protein yield and low clinical mastitis, respectively, identified 27 previously reported BoLA-DRB3.2 alleles across the groups. Significant differences in BoLA-DRB3.2 allele frequencies were found between the selection groups. Alleles *13, *18, *22 and *27 had a significantly higher frequency in cows selected for low clinical mastitis, while alleles *3, *9, *11 and *26 had a higher frequency in cows selected for high protein yield. Associations between BoLA-DRB3.2 alleles and clinical mastitis were analysed based on mastitis data from 741,072 first-lactation NR cows, of which 452 were genotyped. Alleles *22 and *26 were found to be associated with increased clinical mastitis, while alleles *7, *11, *18 and *24 had a favourable effect on mastitis resistance. Contradictory results from different studies investigating associations between BoLA-DRB3.2 alleles and mastitis indicate that future studies should focus on associations of mastitis with BoLA haplotypes rather than with single BoLA genes.  相似文献   
6.
Fifty-nine monoclonal antibodies (mAb) were assigned to the adhesion section of the Second International Swine CD Workshop. They were analysed for their reactivity to selected lymphoid cell populations, as well as to non-lymphoid cell lines. Cell lysate ELISAS and Western Blot analyses were also carried out. As a result, thirteen separate cluster groups emerged (p>0.95). Workshop assignments for adhesion molecules were made: wCD29/49 for mAbs UCP1D2 (#133) and FW4-101 (#165), and PNK-I (#194) and MUC76A (#025) could be assigned to wCD18. For one cluster (FQ1D7, #161 and 2F4, #069) the cellular distribution and MW were characteristic for MHC Class II, and another cluster comprising several antibodies which appeared to recognise MHC Class I. Other clusters could not be assigned to cell surface structures known to be linked to cellular adhesion, however, two further antibodies, 335-2 (#112) and FG1F6 (#156), could be added to SWC1, and the new SWC8 was defined by MIL3 (#077) and MUC20A (#029), binding a ligand of 29–32 kDa. Clustering for these two antibodies was confirmed by blocking studies. The cellular distribution is known for MIL3, recognising an epitope present on granulocytes, B cells, and a subset of T cells expressing CD8 at high intensity.  相似文献   
7.
用含2mol/L尿素的磷酸盐缓冲液以热处理方法提取的K99和F41菌毛作为抗原,对琼脂扩散试验方法进行研究。结果表明本试验方法简便,特异性强,敏感性高,可用于血清抗体检测;所制备的抗原稳定、重复性好。  相似文献   
8.
自然感染日本血吸虫病耕牛血清循环抗原消长规律的研究   总被引:1,自引:0,他引:1  
为了观察疫区自然感染日本血吸虫病耕牛血清循环抗原消长规律,本试验将血吸虫病非疫区的水、黄牛各10头,转运至安徽省血吸虫病疫区,接受为期8周的自然感染。用斑点酶联免疫吸附试验测定牛血清循环抗原。结果,水、黄牛血清循环抗原滴度均于自然感染第4周后明显上升,水、黄牛自然感染第8周的血清循环抗原最高滴度分为1∶10240和1∶5120,最低滴度则分别为1∶1280和1∶640,水牛循环抗原滴度高于黄牛。虫荷数与血清循环抗原滴度未见有相关性。  相似文献   
9.
《Veterinary parasitology》2015,207(1-2):17-33
Salivarian trypanosomes sequentially express only one variant surface glycoprotein (VSG) on their cell surface from a large repertoire of VSG genes. Seven cryopreserved animal trypanosome isolates known as TeAp-ElFrio01, TEVA1 (or TeAp-N/D1), TeGu-N/D1, TeAp-Mantecal01, TeGu-TerecayTrino, TeGu-Terecay03 and TeGu-Terecay323, which had been isolated from different hosts identified in several geographical areas of Venezuela were expanded using adult albino rats. Soluble forms of predominant VSGs expressed during the early infection stages were purified and corresponded to concanavalin A-binding proteins with molecular masses of 48–67 kDa by sodium dodecyl sulfate-polyacrylamide gel electropohoresis, and pI values between 6.1 and 7.5. The biochemical characterization of all purified soluble VSGs revealed that they were dimers in their native form and represented different gene products. Sequencing of some of these proteins yielded peptides homologous to VSGs from Trypanosoma (Trypanozoon) brucei and Trypanosoma (Trypanozoon) evansi and established that they most likely are mosaics generated by homologous recombination. Western blot analysis showed that all purified VSGs were cross-reacting antigens that were recognized by sera from animals infected with either T. evansi or Trypanosoma (Dutonella) vivax. The VSG glycosyl-phosphatidylinositol cross-reacting determinant epitope was only partially responsible for the cross-reactivity of the purified proteins, and antibodies appeared to recognize cross-reacting conformational epitopes from the various soluble VSGs. ELISA experiments were performed using infected bovine sera collected from cattle in a Venezuelan trypanosome-endemic area. In particular, soluble VSGs from two trypanosome isolates, TeGu-N/D1 and TeGu-TeracayTrino, were recognized by 93.38% and 73.55% of naturally T. vivax-infected bovine sera, respectively. However, approximately 70% of the sera samples did not recognize all seven purified proteins. Hence, the use of a combination of various VSGs for the diagnosis of animal trypanosomosis is recommended.  相似文献   
10.
ABSTRACT:   Seawater fishes are affected by a pathology commonly called 'myxobacteriosis', caused by Tenacibaculum maritimum (formerly Flexibacter maritimus ). The disease is characterized by fin erosion and necrotic ulcers of skin and muscle, and by low but constant mortality in cultured marine fish; in Italy is one of the most important and widely spread diseases affecting sea bass Dicentrarchus labrax , gilthead seabream Sparus aurata , sharp-snouted bream Diplodus puntazzo , white bream Diplodus sargus , and six-tooted bream Dentex dentex . In order to obtain an effective vaccine against the disease, formalin killed cells (FKC), extracellular products (ECPs) and crude lipopolysaccharide (LPS) preparations were obtained from the T. maritimum strain SPVId and injected intraperitoneally twice into the sea bass. The fish immune response to the preparations was studied: agglutinating antibody titer and in vitro phagocytosis were determined after the first and second injection in order to evaluate whether the preparations are immunogenic or not and if the booster effect took place. The results show that FKC and LPS preparations increased the antibody titer after the first injection when compared to the control sea bass. Moreover, all the preparations stimulated a secondary (booster) response. In vitro phagocytosis of the total blood was significantly higher for all the preparations when compared to the controls, but the crude LPS immunized sea bass showed the highest activity.  相似文献   
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