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71.
Neal L. Oden 《American journal of physical anthropology》1992,89(2):257-264
Dow and Cheverud (Am. J. Phys. Anthropol. 68:367–373, 1985) have published a statistical test for comparing any three similarity matrices. Using both simulations and analytical arguments, I establish that the presence of spatial autocorrelation, a common feature of geographically based anthropological and biological data, causes this test to reject too often. Increasing the spatial autocorrelation increases the spurious rejection rate. About 20% of the papers that reference Dow and Cheverud's paper have used their test with spatially autocorrelated data. Mantel's (Cancer Res. 27:209–220, 1967) method, when used as a test of spatial autocorrelation, is unaffected by these considerations, since its null hypothesis is that the data are uncorrelated. © 1992 Wiley-Liss, Inc. 相似文献
72.
东北虎微卫星DNA遗传标记的筛选及在亲子鉴定中的应用 总被引:61,自引:0,他引:61
利用18个家猫微卫星基因座,在东北虎(Panthera tigris sibilia)DNA中扩增结果有4个基因座没有产物,8个基因座为单态,6个基因座为多态性。同时利用苏门答腊虎的微卫星序列设计了8对引物,在东北虎DNA中有4对具有多态性。微卫星基因座的多态性百分率为38.5%。在供试的27只东北虎中,发现等位基因间的变异均为偶数碱基长度变化,对有准确谱系记录的个体研究表明,这10个微卫星DNA遗传标记符合孟德尔遗传规律,所以这些微卫星DNA可以有效的应用于东北虎的亲子鉴定。利用这10对多态性引物,我们成功地鉴定了7个父子关系不清的后代。收集的样品包括23只毛发样品和4只血液样品,实验结果表明,毛发和血液样品均可以得到清晰的微卫星条带[动物学报49(1):118—123.2003]。 相似文献
73.
ZENG WenbingZHANG Weicheng XU ShiyuanYANG ZhizhongLIU ChunZHU DepingWEN QibinSHEN QixiangWANG Xianbin 《中国科学:生命科学英文版》1996,39(1):87-98
The mechanism of 13C-methacetin breath test is set forth clearly with the analysis of pharmacokinetics mode, and the measuring method of 13C-methacetin breath test and its clinical applications in the diagnosis of liver diseases are reported in detail. On the basis of comprehensive analysis of the clinical test data, the advanced diagnostic parameter S is of important significance for the application and development of breath test. 相似文献
74.
E. Argese C. Bettiol P. Miana L. Iuzzolino G. Giurin 《Journal of Aquatic Ecosystem Stress and Recovery (Formerly Journal of Aquatic Ecosystem Health)》1996,5(2):125-134
The effects on mitochondrial respiratory parameters of heavy metals, such as Cu, Ni, Pb, Cd, Zn, Ag, Hg, were recorded by using thein vitro response of submitochondrial particles (SMP) from beef heart mitochondria.The toxicity of these elements was estimated by determining their effects on the energy-coupled reverse electron transfer (RET), which is induced by ATP and succinate at first site level of the respiratory chain in SMP.The RET rate was easily monitored by recording spectrophotometrically at 340 nm the production of NADH, arising from the reduction of exogenous NAD+ by RET.The toxicity values were expressed as the toxicant molar concentration which decreases the rate of reduction of NAD+ to an extent of 50 percent (EC50). The toxicity increased in the following order: Ni2+2+2+< Cd2+2+2++.The SMP data were compared with the toxicity values obtained from a variety of biological systems currently used for toxicity testing. The results obtained demonstrate that the SMP test generally provides a good estimate of metal toxicity for several fish and invertebrate species. This is demonstrated by the statistical parameters obtained in the regression analysis. The broadened 95% confidence intervals and, in particular, the poor correlations obtained for some aquatic organisms can be ascribed to the more complex metabolic interactions and competing toxic pathways in aquatic organisms, when compared to SMP. 相似文献
75.
Tetsuya Tanigawa Yasuo Mizo-oku Kouichi Moriguchi Takashi Suzuki Takahiko Osumi Masaaki Odomi 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1996,683(2):135
A simple and rapid quantitative method for 13C-labelled urea ([13C]urea) in human serum was developed by using high-performance liquid chromatography-atmospheric pressure chemical ionization mass spectrometry (HPLC-APCI-MS). This method is used to establish and normalize the [13C]urea breath test, which is considered as an effective diagnostic method for Helicobacter pylori infection. HPLC-APCI-MS, involving a simple pretreatment process such as diluting serum with water, was shown to be able to discriminate the extrinsic [13C]urea from intrinsic urea present at high concentration in serum. In addition, a 13C nuclear magnetic resonance spectroscopic quantitative method for [13C]urea in human urine is also described. The precision and accuracy of measured concentrations in these two methods were found to be within the acceptable limit. An application of these methods to investigate the pharmacokinetic profile of orally administered [13C]urea in human serum and urine is also presented. 相似文献
76.
The mechanism of 13C-methacetin breath test is set forth clearly with the analysis of pharmacokinetics mode, and the measuring method of 13C-methacetin breath test and its clinical applications in the diagnosis of liver diseases are reported in detail. On the basis of comprehensive analysis of the clinical test data, the advanced diagnostic parameter S is of important significance for the application and development of breath test. 相似文献
77.
Dog-DAT: a direct agglutination test using stabilized, freeze-dried antigen for the serodiagnosis of canine visceral leishmaniasis 总被引:2,自引:0,他引:2
Linda Oskam Rob J. Slappendel Eef G.M. Beijer Nel C.M. Kroon Cor W. van Ingen Seray Özensoy Yusuf Özbel Wiepko J. Terpstra 《FEMS immunology and medical microbiology》1996,16(3-4):235-239
Abstract We have evaluated the use of an improved direct agglutination test (DAT) based on stable, freeze-dried antigen for the detection of anti- Leishmania antibodies in canine serum samples. With a cut-off value of 1:640, the sensitivity of the DAT was shown to be 100% and the specificity of the test was 98.8%. 相似文献
78.
79.
80.
本研究对四年生杉木半同胞子代林49个家系的遗传测定结果表明:树高、胸径、冠幅等性状呈高度遗传;枝粗、枝数等性状呈弱度遗传;枝数与大多性状间呈不显著遗传负相关;树高、胸径之间遗传相关显著;冠幅、年轮盘数、枝粗及枝长四者之间遗传相关极显著;该四性状与高、径之间呈极显著遗传相关.采用综合指数选择摸式得指数方程为I=1.647P1 2.993P2 1.522P3 0.086P4-0.ll7P5-1.779P6-1.995P7,据此选出遗传型最佳家系,并分析了综合指数选择法的合理性和有效性. 相似文献