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31.
本文对203名青少年白发患者的皮纹进行了分析,并与216名正常对照组个体作了比较.发现青少年白发组的As和Wd出现率以及A/A和L/W的对应频率均显著低于正常对照组;青少年白发组女性的a-bTRC值、男性变异型掌褶纹的出现率、10指同斗频率、右手Ⅰ2区及左手Hy区的花纹出现率均显著高于正常对照组的相应出现率.说明青少年白发者的皮纹可能有自身的遗传特征。 Abstract:This paper sought to analyze the dermatoglyph of 203 cases with juvenile poliosis,and make an individual contrast with the control group of 216 normal juveniles.It was found that the incidence of As and Wd in the group of juvenile poliosis and the correspondence rate of A/A and L/W were obviously lower than those of the normal contrast group,while a-b TRC value in the female patients with juvenile poliosis and the incidence of abnormal palmprint in the male, the frequency of all loop whorl,and palm patterns in the I2 area of the right hand and in the Hyarea of the left hand were evidently higher than the corresponding incidences of the normal contrast group.Dermatoglyph of the juvenile poliosis has its own heredity.  相似文献   
32.
Shigella spp are the pathogen of bacillary dysentery, the leading intestinal contagious disease in China. According to the O antigen, Shigella spp can be sub-grouped into four species: S.dysenteriae, S. flexneri, S. boydii and S. sonnei, also known as Shigella sub-groups A, B, C and D. In developing countries, S. dysenteriae A1, one of the thirteen serotypes in A sub-group, resulted in extremely serious bacterial diarrhea with mortality of 7%[1]. Traditional classifications were unsucces…  相似文献   
33.
硅对生姜叶片水、二氧化碳交换特性的影响   总被引:5,自引:0,他引:5  
为探讨硅对生姜植株的生理效应,以莱芜大姜为试材,研究了水培营养液中不同硅素水平对生姜植株生长、硅含量及叶片光合作用和蒸腾作用的影响.结果表明:植株各器官硅含量及生物量均随营养液硅素水平的升高而显著增加,1.0 (T1)、1.5 (T2)、2.0 (T3) mmol·L-1硅(Si)处理植株叶片硅 (SiO2) 含量分别比CK增加604.4%、834.8%和1130.4%,单株生物量分别比CK增加9.4%、19.4%和22.8%.随着硅素水平的升高,叶片Mg2+ TPase、Ca2+ ATPase活性及光合速率(Pn)和水分利用效率(WUE)提高,蒸腾速率(Tr)降低.一天中在11:00时,T1、T2、T3处理的生姜叶片Pn和WUE分别比CK提高11.2%、21.8%、28.2%和23.1%、55.9%、54.8%,Tr分别比CK降低6.3%、17.1%和19.2%.此外,硅素还显著提高了生姜叶片光合作用饱和光强、CO2羧化效率及类胡萝卜素含量,但对叶绿素含量无显著影响.本试验条件下,以15~20 mmol·L-1硅素(Si)处理效果最好.  相似文献   
34.
超高产夏玉米田土壤微生物与土壤酶的动态变化   总被引:3,自引:0,他引:3  
为揭示超高产夏玉米田(产量>15 000 kg·hm-2)土壤微生物与土壤酶活性动态变化特性,在国家玉米工程技术研究中心(山东)试验场进行夏玉米生长季农田土壤微生物与土壤酶活性研究. 在连续3年产量15 000 kg·hm-2以上的超高产夏玉米田中选择一块超高产田(HF, 产量为20 322 kg·hm-2)与常规生产田(CF, 产量为8920.1 kg·hm-2)进行对比分析,主要测定0~20 cm土层土壤细菌、真菌与放线菌数量及脲酶和转化酶活性. 结果表明:播种后超高产田与常规生产田土壤微生物(细菌、真菌与放线菌)数量均表现出先升高后下降的趋势,超高产田在玉米生长后期土壤微生物数量低于常规生产田,细菌与放线菌表现尤其明显,收获期超高产田B/F值(细菌与真菌数量比)比播种期高2.03倍,比常规生产田高3.02倍,常规生产田收获期与播种期的B/F值变化不显著;超高产田土壤脲酶活性在播种31 d(拔节期)后低于常规生产田,转化酶活性播种58 d(开花期)后快速下降,低于常规生产田.  相似文献   
35.
Elevated expression of the rotavirus VP6 antigen in transgenic plants is a critical factor in the development of a safe and effective rotavirus vaccine. Using codon optimization, a gene that encodes the inner capsid protein VP6 of the human group A rotavirus was synthesized (sVP6). The VP6 and sVp6 genes were transformed into tobacco (Nicotiana tabacum L.) plants using Agrobacterium tumefaciens. The expression level of the sVP6 gene in transgenic plants was 3.8-34-fold higher than that of controls containing the non-modified VP6 gene, accounting for up to 0.34% of the total soluble protein (TSP). Then, BALB/ c female mice that had been gavaged weekly with 10 mg TSP containing 34 p.g VP6 protein, in which VP6-specific serum IgG and mucosal IgA antibodies were investigated. The severity and duration of diarrhea caused by simian rotavirus SA-11 challenge were reduced significantly in passively immunized pups, which indicates that anti-VP6 antibodies generated in orally immunized female mice can be passed onto pups and provide heterotypic protection. An edible vaccine based on the VP6 of human rotavirus group A could provide a means to protect children and young animals from severe acute diarrhea.  相似文献   
36.
Superficial fungi are the etiologic pathogens of various dermatophytoses, such as tinea capitis, tinea corporis, tinea inguinalis, tinea manus, tinea unguium and tinea pedis. These widespread infections affect up to 25% of the worlds population, a percentage that has continued to increase in recent years. T. rubrum is the most common superficial fungus, accounting for at least 60% of all infections of this type. T. rubrum can induce dermatophytoses in different parts of the hu-man skin, and ca…  相似文献   
37.
用 5mmol/L PARP抑制剂苯甲酰胺处理经c-Ha-T24-ras活化癌基因转染得到的转化细胞系, 处理4周后发现转化细胞系的某些细胞生物学特性发生了改变,呈现出正常细胞的某些特性。伴随这一现象,检测到细胞中整合的外源T24-ras基因发生了丢失。 Abstract:A transformant line obtained by transfection of NTH3T3 cells with c-Ha-T24-ras gene was treated with 5mmol/L benzamide,an inhibitor of PARP enzyme for 4 weeks.Some changes in cellular properties of the transformant line were observed.Concomitant with these changes was the deletion of the exogenous c-Ha-T24-ras which had been integrated into genomic DNA of recipient cells.  相似文献   
38.
Responses of caryopsis germination, seedling emergence, and development of Agropyron cristatum (L.) Gaertn. (Gramineae) and Bromus inermis Leyss. (Gramineae), two dominant perennial grasses in the Otindag Sandland of China, to different sand water content (SWC; 1%, 2%, 3%, 4%, 6%, 8%, 12%, 16%, and 20%) were studied comparatively. The results showed that the germination responses of the two grasses to SWC were similar (i.e. caryopses could not germinate when the SWC was below 3%; at SWC ranging from 3% to 12%, the higher the SWC, the higher the germination percentage; and at a SWC of 12%-20%, germination reached similarly high percentages). At a sand burial depth of 0.5 cm, the threshold of SWC for seedling emergence was 6% forA. cristatum and 8% forB. inermis; at 12%-20% SWC, the seedling emergence of both species reached similarly high percentages. The seedling growth responses of these two species to SWC gradients were different. For A. cristatum, the biomass of seedlings increased with SWC from 6% to 12%, and decreased with SWC from 12% to 20%. For B. inermis, the biomass of seedlings always increased with SWC from 8% to 20%. The results also showed that the seedlings of both species allocated more biomass to the roots with decreases in SWC. The SWC changes from April to October in natural microhabitats of both species suggested that the SWC may play an important role in caryopsis germination, seedling emergence, and the growth characteristics of the two grasses. The responses of caryopsis germination, seedling emergence, and the growth characteristics of these two species to SWC may determine their distribution pattems in the Otindag Sandland.  相似文献   
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40.
1 Introduction The prediction of protein structure and function from amino acid sequences is one of the most impor-tant problems in molecular biology. This problem is becoming more pressing as the number of known pro-tein sequences is explored as a result of genome and other sequencing projects, and the protein sequence- structure gap is widening rapidly[1]. Therefore, com-putational tools to predict protein structures are needed to narrow the widening gap. Although the prediction of three dim…  相似文献   
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