双标记水法测量54例4和6月龄婴儿体成分

为了解 4和 6个月婴儿的体成分组成情况 ,使用双标记水稀释法测量 5 4名健康婴儿总体水(TBW)、瘦体重 (LBM)和脂肪含量。结果表明 ,4个月婴儿的TBW、LBM和脂肪的重量分别为 (4 2 7± 0 4 7)、(5 11± 0 6 6 )和 (2 13± 0 5 7)kg。 6个月婴儿的TBW、LBM和脂肪的重量分别为 (4 5 9± 0 5 8)、(5 77± 0 73) ,和 (2 0 1± 0 6 6 )kg。而且 4和 6个月婴儿体成分中各组成成分占体重的百分含量没有性别差异。但是在两个月龄婴儿组中分别按照不同喂养方式分组进行分析时 。

用双标记水示踪法测定人体自由活动时的能量消耗率

本文报道用１８Ｏ和２Ｈ双标记水测定人自由活动时能量消耗率的示踪方法及正常成人的初步测定结果。根据质谱测量精度将ＨＯ和２Ｈ２Ｏ测量定为１．０ｇ／ｋｇ（丰度１４．４５％）和０．０６ｇ／ｋｇ（丰度９９．９％），一次口服后在１４ｄ内间歇性收集尿样５次，然后从１８Ｏ和２Ｈ时相曲线斜率的差别，并加入同位素分馏校正因子，算出整体ＣＯ２产生率，再根据食物组成估计呼吸商，求出能量消耗率。测得１０例正常实验室工作人员的结果是：男性和女性平均为２０８．８±１４．２和１９２．０±２３，ｋＪ·ｋｇ－１·ｄ－１。３例住院康复人员平均为１５４．０ｋＪ·ｋｇ－１·ｄ－１。

^(18)O和~2H标记水测定人的总体水

报道了用稳定核素Ｈ２１８Ｏ和２Ｈ２Ｏ同时一次口服作示踪实验测定总体水量的初步研究。结果表明，Ｈ２１８Ｏ多点示踪法最可靠。从临床应用出发，如以Ｈ２１８Ｏ多点法为参考标准，对２Ｈ２Ｏ多点法及４ｈ单点法的差别求出一定校正，则这些方法也可考虑选用．

应用双标记水法测量人体20 d能量消耗的剂量方案优化

目的分析不同双标记水法实验方案在测量20 d能量消耗时结果的可靠性。方法 18名受试者随机均分为3组,分别采用普通剂量(A组)、追加服用(B组)、增加剂量(C组)3种实验方案对其20 d(其中前15日为卧床状态)能量代谢进行测量。通过"国际原子能机构人体健康系列第三部分"中对实验结果判别标准进行可靠性判断。结果普通剂量组20 d尿样同位素丰度及原子比浓度均达不到标准,15日尿样结果各项判别标准均达标;追加服用组和增加剂量组20 d尿样结果均符合各项标准。结论使用双标记水法测量20 d人体能量代谢时,可以使用追加服用次数或者增加服用剂量的方法,不能使用普通剂量的方法。

运用标记水测定动物水周转率

动物有机体不断与周围发生着水交换,而维持内环境的相对稳定是动物基本特征之一。因而研究动物水平衡状况成为生理生态学主要内容。虽然已积累相当多的资料,如测定肺皮失水量、尿浓度、肾脏指数等等,但绝大部分为实验室条件下的结果,实际应用受到限制。生态学家一直在寻找能够在自然状况下反映动物水代谢的示踪物,先后用作示踪物的有尿素、

同位素双标记水技术及其在动物生态研究中的应用

氢和氧元素均有三种同位素,氘（H2）、O17、O18为稳定性同位素,不具有放射性,特别适用于那些特殊实验对象,如人。但样品制备复杂,测量比较困难,费用昂贵。氚（H3）是半衰期为12.3年的放射性同位素,释放射线为软β,软β穿透能力较弱,空气中最大射程不足1 mm,故 H3为一种较安全的放射性同位素。其优点较多,分析测量和样品制备简便、精确、测量费用和同位素费用均很少。故常用的为 HH3O18双标法。所谓双标记水,就是将一定浓度的 HTO和 H2O18混合,然后注射到动物体内,通过扩散与体内总体水达到平衡。

Mapping of S-b Locus for F_1 Pollen Sterility in Cultivated Rice Using PCR Based Markers

In cultivated rice ( Oryza sativa L.), F-1 pollen sterility is controlled by at least 6 loci of the F, pollen sterility genes. To map S-b, one of loci, rice variety Taichung 65 (T65) carrying S-b(j)/S-b(j) and its near-isogenic line TIST2 carrying S-b(i)/S-b(i) were used to develop the mapping population. One hundred and fifty-eight microsatellite markers were selected to survey T65 and TISL2. RM13 on chromosome 5 was found to be polymorphic between them. Cosegregation indicated that RM13 was closely linked with locus S-b. Eleven RFLP markers were selected on the corresponding region from the genetic map of Rice Genome Research Program (RGP) of Japan to convert into sequence-tagged site (STS) markers. Amplicon length polymorphism (ALP) was carried out, but none of them was found to be polymorphic between T65 and TISL2. Then PCR-based RFLP (PBR) was done using six 4-nucleotide recognizing restriction endonucleases. Polymorphism was detected when PCR products of R830STS and R2213SSTS were digested with Taq I. Genetic analysis indicated that the distance between locus S-b and markers, R830STS, RM13 and R2213SSTS were 3.3 cM (centi-Morgan), 5.2 cM and 5.5 cM, respectively. These PCR-based markers could be directly used in marker-assisted selection. The technical system combining genetic mapping and PCR-based marker-assisted selection will facilitate the development of molecular breeding.

Improvement of Resistance to Rice Blast in Zhenshan 97 by Molecular Marker-aided Selection

Fungi blast is one of the most serious diseases of rice worldwide. Breeding resistant varieties have been proved to be the most effective and economical means to control the disease. This paper describes the molecular marker-assisted selection (MAS) procedure for a broad-spectrum blast resistant gene Pi1 integrated into an elite hybrid maintainer line, Zhenshan 97. A simple sequence repeat (SSR) based on molecular marker-aided selection system for Pi1 segment was established. Using a backcross population and a blast isolate F1829, Pi1 gene was mapped on the top of chromosome 11 between markers RZ536 and RM144, with a distance of 9.7 cM and 6.8 cM, respectively. Seventeen families derived from the recurrent parent Zhenshan 97 were obtained with homozygous Pi1 gene. The background of the 17 families was identified with inter simple sequence repeat (ISSR) amplification, the highest recovery of the Zhenshan 97 genetic background was 97.01% after the assay of 167 polymorphic bands.

Primary Study of Rice AFLP Analysis Optimization of Reaction Conditions and Analysis of Thermo sensitive Genic Male Sterile Rice Allelic Mutant Lines

AFLP analysis was performed between a pair of thermo_sensitive genic male sterile (TGMS) rice allelic mutant lines (5460S and 5460F). The reaction conditions for rice AFLP assay were optimized. The relative efficiencies for polymorphism detection of RFLP, RAPD and AFLP were compared. The results indicated that the efficiency for polymorphism detection in rice was in the order of AFLP>RAPD>RFLP, and also indicated that AFLP was a powerful DNA molecular marker technique for polymorphism detection, especially in the case of extremely low polymorphism, such as isogenic lines and allelic mutant lines. Some of the AFLP products between the TGMS rice allelic mutant lines were cloned. Three of them were used as mixed probes to screen BAC library of rice line 5460S. 12 positive clones were screened out. In addition, the advantages and disadvantages of these three molecular marker systems were discussed.

Segmental Duplications Are Common in Rice Genome

Segmental duplications on rice (Oryza sativa L.) chromosomes 8, 9, 11, and 12 were studied by examining the distributions of sequences resolved by 13 probes detecting multiple copies of DNA sequences. Four of the hybridization bands detected by a repetitive sequence probe, rTRS, were mapped to the ends of all the four chromosomes. Two or three of the bands detected by each of the other 12 probes were also mapped to different chromosomes. The bands detected by the same probe usually occurred in similar locations of different chromosomes. Loci detected by different DNA probes were often similarly arranged on different chromosomes. Chromosomes 8 and 9 showed colinearity of marker loci arrangement indicating a possible common origin. A segment on chromosome 9 was also very similar to the previously reported duplicated fragments on the ends of chromosomes 11 and 12 which were also detected in this study, indicating a likely common origin. Moreover, the various degrees of distributional similarity of the segments suggest a complex relationship among the chromosomes in the evolution of the rice genome. These results support the proposition that chromosome duplication and diversification may be a mechanism for the origin and evolution of the chromosomes in the rice genome.

Comparative Physical Localization of Rice Pib Gene and Its Linked RFLP Markers in Oryza sativa, O. officinalis and Zea mays

Comparative genetic studies have shown that there are widespread synteny and colinearity of the genes among different species within grass family. Rice ( Oryza sativa L.) is a model plant, and analysis of its genome allows us to reveal the common features and the evolutionary rules of the gramineous genomes and accumulate the data for establishment of a common genetic system in the Poaceae. In this study, a rice gene Pib ( 10.3 kb), a map-based cloned gene, and RFLP markers linked with it are used as the tested probes to investigate their homology and physical location among the tested species. Southern blotting analysis showed that there were sequences homologous to Pib in maize genome. Further, Pib was localized onto the chromosomes of O. sativa ssp. indica cv. Guangluai 4, O. officinalis Wall ex Watt and the inbred line of Zea mays cv. Huangzao 4. The results of fluorescence in situ hybridization (FISH) and double-color FISH indicated that a synteny of Pib and RFLP markers linked with Pib existed among the genomes of the three tested species.

人体生理学

0107971 再生医学的现状和面向实用化[日]/平野隆∥现代医疗.-1999,31(12).-2～19 冀医情 0107972 供氧适当的老年人在自然状态下体力更充沛吗?一项双标记水法研究/

儿童肥胖症的危险因素

通过对肥胖症高危人群的前瞻性研究,对人类肥胖症的认识大大加深。高危人群能够被识别是因为肥胖症有很强的家族性。例如,Roberts及其同事应用双标记水(doubly labelled water)试验法估计总能量消耗,发现在3个月时,能量消耗/单位体重较低的一些婴儿在12个月时变成肥胖儿,但是那些代谢率较高的儿童未变成肥胖儿。Ravussin等人发现了类似的情况:成年印地安人的静止代谢率低(RMR)与4年后体重增加有高度相关性。因此,低代谢率/公斤体重加上父母有肥胖症是发生肥胖症的危险因素。

A Scheme of Fragile Watermarking Based on SVD and 2D Chaotic Mapping

This paper proposed a novel fragile watermarking scheme based on singular value decomposition (SVD) and 2D chaotic mapping. It obtains chaotic initial values from the image blocks singular value decomposition and the user’s key, then uses the chaotic mapping to get the chaotic sequence and inserts the sequence into the LSBs of the image blocks to get the watermarked image blocks. The paper reconstructed the watermarked image from all the embedded blocks. The analysis and experimental results show that the scheme is pretty fragile to tampering, and it can localize the tampering position accurately, reach 3×3 blocks.

A robust watermarking algorithm based on significant-tree in Contourlet domain

An adaptive algorithm operating in the Contourlet domain is presented. Contourlet is a new image sparse representation, which is better than a wavelet for piecewise smooth images with smooth contours. Because of flexible multiresolution, local and directional sensitivity of Contourlet transform, our approach also defines significant-tree in the Contourlet domain. By analyzing the relation of the Contourlet coefficients, we embed the watermarking into all the coefficients of each significant-tree. Then referring to the statistical properties of the coefficients, the masking characteristics of texture are defined for adaptively controlling the embedding strength. Experimental results show that the proposed algorithm is highly robust to various attacks, such as JPEG compression, medium filtering, cropping and rotation. Furthermore, comparisons with a classical method in the wavelet domain prove the validity of the new algorithm.

Preoperative detection and localization of small bowel hemangioma: Two case reports

Among the various diagnostic modalities for small bowel hemangioma, video capsule endoscopy (VCE) and double-balloon enteroscopy (DBE) can be recommended as part of the work-up in patients with obscure gastrointestinal bleeding (OGIB). DBE is superior to VCE in the accuracy of diagnosis and therapeutic potential, while in most cases total enteroscopy cannot be achieved through only the antegrade or retrograde DBE procedures. As treatment for small bowel bleeding, especially spout bleeding, localization of the lesion for the decision of DBE insertion facilitates early treatment, such as endoscopic hemostatic clipping, allowing patients to avoid useless transfusion and the worsening of their disease into life-threatening status. Applying endoscopic India ink marking prior to laparoscopic surgical resection is a particularly useful technique for more minimally invasive treatment. We report two cases of small bowel hemangioma found in examinations for OGIB that were treated with combination of laparoscopic and endoscopic modalities.

Genotype Analysis of Yuzhenxiang, a Long Grain, High Quality Aromatic Rice Cultivar

In China,the market share of a rice cultivar is mainly determined by its yield and quality.Yuzhenxiang is a high-quality variety with extra-slender grain shape,good quality and unique aroma.In order to investigate its genetic background,12 pairs of functional markers were used to detect the genotype distribution of eight major grain shape genes including GS3,GW5,GS6,GW6a,GL7/GW7,GLW7,GW8,GS9,one amylase gene Wx and one aroma gene BADH2 in Yuzhenxiang by using Nipponbare,9311,Huazhan,Zhonghui 8015 and Zhonghui 9308 as controls.The results indicated that the slender grain type of Yuzhenxiang was probably affected by GS3 and GL7/GW7 with the positive co-regulation of multiple grain shape genes,and its outstanding rice quality may be resulted from the cumulative effects of GLW7,GW8 and Wx genotypes,while its unique aroma may be mainly regulated by BADH2-E7 deletion.

Development of 101 Novel EST-Derived Single Nucleotide Polymorphism Markers for Zhikong Scallop (Chlamys farreri)

Zhikong scallop(Chlamys farreri) is an important maricultured species in China.Many researches on this species,such as population genetics and QTL fine-mapping,need a large number of molecular markers.In this study,based on the expressed sequence tags(EST),a total of 300 putative single nucleotide polymorphisms(SNPs) were selected and validated using high resolution melting(HRM) technology with unlabeled probe.Of them,101(33.7%) were found to be polymorphic in 48 individuals from 4 populations.Further evaluation with 48 individuals from Qingdao population showed that all the polymorphic loci had two alleles with the minor allele frequency ranged from 0.046 to 0.500.The observed and expected heterozygosities ranged from 0.000 to 0.925 and from 0.089 to 0.505,respectively.Fifteen loci deviated significantly from Hardy-Weinberg equilibrium and significant linkage disequilibrate was detected in one pair of markers.BLASTx gave significant hits for 72 of the 101 polymorphic SNP-containing ESTs.Thirty four polymorphic SNP loci were predicted to be non-synonymous substitutions as they caused either the change of codons(33 SNPs) or pretermination of translation(1 SNP).The markers developed can be used for the population studies and genetic improvement on Zhikong scallop.