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311.
Cross-Strait relations remain deadlocked following Chen Shui-bian's inauguration as Taiwan's president. Amid this political stalemate, Chen's administration decided to change the 'no haste, be patient' ( jie-ji yueng-ren ) policy while refusing to endorse the 'one China' principle. While this policy change is in response to domestic demands, Chen and his ruling Democratic Progressive Party (DPP) are unlikely to reap any benefit from these actions without active cooperation from China's leaders. Beijing will continue to use its economic clout in an attempt to pull Taiwan into political union, as Taipei needs to nurture an environment favourable for domestic and foreign investment in Taiwan in order to maintain its competitive edge over China and thus preserve its de facto independence. Beijing's leaders will need to rethink their rigid stand on the 'one China' principle, since increased cross-Strait economic integration may not lead to the expected political union they desire.  相似文献   
312.
To estimate postmortem interval (PMI), spontaneous cleavage of the third component of complement (C3) was studied in aged blood and cadaveric blood by crossed immunoelectrophoresis. Using the kinetics of C3 cleavage in vitro described as dC/dt = -kC, where C is the concentration of native C3 at time t and k is a first-order rate constant, Arrhenius' equation, and another equation which assumes a linear drop of body temperature after death, the percentages of C3 cleavage were calculated. There was a significant positive correlation between the calculated percentages and the measured percentages of up to 10% in cadaveric blood. We found that the comparison between the calculated percentage of C3 cleavage for each optional postmortem interval and the measured percentage of up to 10% in cadaveric blood leads to the estimation of PMI. This approach is one step towards the development of an accurate method for determining PMI based on C3 cleavage, that is, on a first-order reaction.  相似文献   
313.
314.
Ethylamphetamine and two major metabolites in urine, obtained after intraperitoneal administration of the drug to rats, have been isolated by gas chromatography-mass spectrometry. We have also synthesized an authentic sample of p-hydroxy-N-ethylamphetamine by a simple method. In rat, the metabolic pathway of ethylamphetamine is similar to that of amphetamine and methylamphetamine according to quantitative analysis of the major metabolites using a selected ion monitoring (SIM) method.  相似文献   
315.
Abstract At times, the American political parties are so close in terms of policy positions that critics denounce the lack of a “dime's worth of difference” between them. At other times, the gap between them on a left‐right dimension is huge. How can we explain this variation? We argue that parties can behave rationally as collective units, and that shifts in divergence and convergence can be explained as rational responses to changes within governmental institutions and to shifts in conditions outside. We analyze this argument using adjusted ADA scores (Groseclose, Levitt, and Snyder 1999) to compare voting score differences between the Democratic and Republican parties in Congress from 1952 to 1996. We pose specific hypotheses for potentially important factors shaping party behavior and test them with a multivariate model. Our results support the argument that the variation in the behavioral gap between the two parties in Congress can be explained as rational party responses to internal and external stimuli.  相似文献   
316.
Using ABH enzyme-labeled monoclonal antibodies, the authors could rapidly detect the ABO group from body fluids and body fluid stains by the dot enzyme-linked immunosorbent assay (dot-ELISA). In this test, the antigen was immobilized on nitrocellulose paper; the entire piece of paper was coated with an appropriate dilution of enzyme-labeled McAb directly against the antigen of interest; and, finally, 3,3'-diaminobenzidine (DAB) substrate solution was added. The site of a positive reaction is clearly visible as a brown spot. We analyzed 521 samples and got satisfactory results. We also analyzed 99 practical case samples by this method and achieved the same results as those obtained by other researchers using other methods. This method is accurate, simple, direct, rapid, and sensitive; it also produces easily observed results, requires no equipment, and can be completed in 30 min. The test proved to be clearly more sensitive for the detection of the ABO blood group in secretor saliva than the conventional hemagglutination inhibition test. Also saliva diluted 10(-4) to 10(-5) and the ABO group of nonsecretor saliva and urine could be easily detected by this method.  相似文献   
317.
A genetic locus (D1S58, defined by DNA probe pMCT118) that contains a variable number of tandem repeats (VNTR) has been successfully amplified from a very small amount of genomic deoxyribonucleic acid (DNA) by the polymerase chain reaction (PCR). The DNA sequence of the locus was determined and was found to consist of a 16-base consensus sequence and flanking sequences. Oligonucleotide primers complementary to the flanking sequences were synthesized to serve as primers for amplification of MCT118 by the PCR method. Human genomic DNA isolated from blood (2 ng from each sample) was successfully amplified at the MCT118 locus, and polymorphic bands were detectable by ethidium bromide staining after electrophoresis on polyacrylamide gels. Determination of genotypes at this VNTR locus can now be routinely achieved within 24 h, without the need for Southern blots or radioactive materials. Furthermore, the small size (387 to 723 base pairs) of the DNA fragments produced in the PCR amplification permits good resolution of individual alleles that differ by only one repeat unit. The precise specification of the number of tandem repeats present in each allelic fragment is reproducible from one analysis to another.  相似文献   
318.
The authors report studies on four pairs of donors and recipients in bone marrow transplantation (BMT). A broad range of gene markers at 41 gene loci, including 11 red blood cell markers, 5 human lymphocyte antigen (HLA) types, 12 serum protein markers, 5 red cell enzyme markers, and 8 salivary markers were evaluated before and after BMT over 2 months. As a result, 9 out of 41 gene loci of genetic markers in recipients were transformed into the donor type. BMT between family members may lead to transformation of gene markers, but within a pattern compatible with family inheritance patterns, and no genetic paradox will be found in later surveys of familial genetic relationships. However, in a personal identification system in forensic medicine using genetic markers as an index, the appearance of a phenotype incompatible with a blood relationship is possible after BMT with a non-blood-relative donor. This result is similar to the inheritance pattern observed after artificial insemination by a donor's semen (AID), a more complete out-of-family cross.  相似文献   
319.
320.
Positive-ion electron impact (PIEI), positive-ion chemical ionization (PICI) and negative-ion chemical ionization (NICI) mass spectra of 19 phenothiazines are presented. In the PIEI mode, peaks due to M, M minus side chain (M - R1), M - R1 + H, and side chain itself (R1) appeared for most compounds. The M - R1 and R1 ions were very useful for drug screening. In the PICI mode, most spectra showed base or intense peaks due to M + H, and small peaks due to M + C2H5; peaks due to M - R1 + 2H and R1 also appeared in many compounds. In the NICI mode, fragmentation modes were different in different compound groups; molecular or [M - H]- quasi-molecular anions appeared in many compounds with aliphatic side chains. Anions at m/z 98 and 115 were characteristic for compounds with (N-methylpiperazinyl)propyl side chains. Selected ion monitoring in the PIEI mode generally gave much higher sensitivity than in the PICI and NICI modes. Phenothiazines present in urine or plasma could be rapidly isolated by use of Sep-Pak C18 cartridges. Thirteen of 19 phenothiazines could be detected by HP-17 wide-bore capillary gas chromatography with satisfactory separation from impurities in their underivatized forms.  相似文献   
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