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SUMMARY. The human platelet alloantigens HPA-1, -2, -3, -5 and -6b in the Finnish population were determined using allele specific restriction analysis (PCR-ASRA) for HPA-1, -2, -3 and -5 and monoclonal antibody immobilized platelet antigen (MAIPA) assay for HPA-1, -3a, -5b and -6b. No discrepancies were observed between the results obtained with the PCR-method and those obtained serologically. The gene frequencies obtained from 200 unrelated Finns were 0.86 and 0.14 for HPA-1a and -1b, 0.91 and 0.09 for HPA-2a and -2b, 0.59 and 0.41 for HPA.3a and -3b and 0.95 and 0.05 for HPA-5a and -5b. The frequency of the HPA-5b allele (10%) is lower in Finns than in Central- or South-European populations (20–30%). The HPA-1, -2 and -3 frequencies did not deviate from those observed in other European populations. The rare HPA-6b antigen was observed in three of 127 individuals from south-eastern Finland (2.4%), which suggests that the frequency of this allele in Finland is higher than previously thought.  相似文献   

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Sepsis induces extensive lymphocyte cell death that may contribute to immune depression and morbidity/mortality in the disorder. bcl-2 is a member of a new class of oncogenes that prevents cell death from an array of noxious stimuli. Transgenic mice that overexpress BCL-2 in T lymphocytes are resistant to sepsis-induced T cell apoptosis, and mortality was decreased in sepsis. The purpose of this study was to identify key initiator and executioner "caspases" involved in sepsis-induced lymphocyte apoptosis and to determine if BCL-2 acts prior to caspase activation. Thymi were removed 5-22 h post-cecal ligation and puncture (CLP) or sham surgery. Apoptosis was evaluated in thymocytes by annexin-V FITC labeling and flow cytometry. Caspase-1 activity was determined by western blot analysis of the procaspase protein and p20 subunit of the activated caspase; activities of caspases -2, -6, and -9 were determined by colorimetric assays using specific substrates conjugated to a color reporter molecule. Caspase-3 activity was determined both by western blot and by a fluorogenic assay in which a fluorescent compound was generated. Thymocytes from CLP mice had markedly increased apoptosis and activation of caspases -2, -3, -6, and -9 in comparison with thymocytes of sham-operated mice. Caspase-1 was not activated. BCL-2 prevented sepsis-induced thymocyte apoptosis and inhibited activation of all caspases. We conclude that sepsis causes activation of multiple caspases and that BCL-2 acts upstream as an inhibitor of caspase activation. The pattern of caspase activation suggests a mitochondrial mediated pathway.  相似文献   

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Nylons have great potential for electrical applications requiring high polarizability and low dielectric loss. Recently, the narrow single hysteresis loop with relaxor ferroelectricity and the double hysteresis loop due to antiferroelectricity have been reported in nylon random copolymers, terpolymers, and common even-numbered nylons. Although several studies of ferroelectric nylons have been reported, even–even-numbered and odd–even-numbered nylons have not been sufficiently explored. Here, the ferroelectricity of spin-coated even–even-numbered and odd–even-numbered nylons was investigated. A series of even–even-numbered nylons, including nylons 6-12, 10-12, and 12-12, and an odd–even-numbered nylon, nylon 11-12, were polymerized with 1,10-dodecanedicarboxylic acid (12) and four aliphatic diamines with various methylene units, 1,6-hexanediamine (6), 1,10-decanediamine (10), 1,11-undecanediamine (11), and 1,12-dodecanediamine (12). The obtained nylon polymers were spin coated and then subjected to melt-quenching or thermal annealing followed by quenching. From the X-ray diffraction and the electrical hysteresis loop data, the correlation between the ferroelectricity and the crystal parameters of crystallinity and crystallite size of the γ crystal phase was investigated. Furthermore, the free volume of the nylon samples was estimated to correlate with the ferroelectricity. Temperature-dependent ferroelectricity was investigated for nylon 10-12. At a high temperature, the nylon samples showed a narrow polarization–electric field hysteresis loop and a rhombus-shaped polarization current–electric field hysteresis loop due to the relaxor ferroelectricity. This behaviour was caused by electrically rotating the nanodomains with weakened hydrogen bonds at higher temperatures.

Nylons have great potential for electrical applications requiring high polarizability and low dielectric loss.  相似文献   

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Pharmacokinetics of (+/-)-, (+)-, and (-)-gossypol in humans and dogs   总被引:2,自引:0,他引:2  
Pharmacokinetic parameters of (+/-)-, (+)-, and (-)-gossypol were determined in humans and dogs after a single oral or intravenous dose. Mean (+/- SD) oral bioavailability of (+/-)-gossypol in dogs was 30.9% +/- 16.2%. Studies in dogs who received single intravenous injections revealed that the elimination t1/2 and volume of distribution of (+)-gossypol were five and six times those of (-)-gossypol, respectively, whereas total body clearance and the AUC of the two enantiomers were similar. Data from men receiving the compounds orally show that the average peak plasma concentration and the AUC of (+)-gossypol are significantly greater than those of the (-)-isomer. The rate constants of alpha, beta, ka, k21, and k10 for (-)-gossypol are significantly greater than those for (+)-gossypol, indicating higher rates of mass transfer of the (-)-species. In humans the elimination t1/2 of (+)-gossypol was 29 times as that of (-)-gossypol, a difference that is more striking than that found in dogs. The elimination t1/2 of (+/-)-gossypol in humans averages 286 +/- 179 hours.  相似文献   

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Comparison of chewing cycles in 2-, 3-, 4-, and 5-year-old normal children   总被引:1,自引:0,他引:1  
Chewing movements of normal 2-, 3-, and 4-year-old children were measured. Chewing movements of 2- and 3-year-olds were compared with those of 4- and 5-year-olds. Measures were taken on 56 children: 17 were 2 years old (8 female, 9 male); 19 were 3 years old (10 female, 9 male); and 20 were 4 years old (10 female and 10 male). Data of twenty 5-year-olds (10 males, 10 females) were taken from a previous study (9). Chewing movements were measured by time (seconds), number of cycles, and a time/cycle ratio. A chewing cycle was defined as an upward and downward movement of the chin. Total time from the moment food was placed in the mouth until the final swallow occurred was divided by the number of cycles counted for the same period. The type of food eaten affected time, cycles, and the time/cycle ratio, but age and sex did not. A comparison of younger (2- and 3-year-olds) and older children (4- and 5-year-olds) showed significant time differences. During maturation, time was shortened. It was shown earlier that under pathologic conditions (Down's syndrome) time was prolonged. Thus, the time/cycle ratio is an excellent indicator of the developmental status of a child.  相似文献   

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Tumor markers are noninvasive diagnostic tools for cancer. Their abnormal expression often occurs earlier than clinical symptoms or other detection signals. Appropriate reference intervals (RIs) of tumor markers are important for health evaluation, cancer diagnosis, therapy monitoring and prognosis assessment. In this study, we aimed to establish the RIs of cancer antigen 125 (CA125), CA15-3, CA19-9, CA72-4, alpha fetoprotein (AFP), carcino-embryonic antigen (CEA), neuron-specific enolase (NSE) and cytokeratin 19 fragment antigen 21–1 (CYFRA21-1) in apparently healthy Henan population. A total of 1705 apparently healthy participants (21–89?years) were recruited from five representative geographical regions in Henan province. Nonparametric 95th percentile intervals were used to define the RIs of CA125, CA15-3, CA19-9, CA72-4, AFP, CEA, NSE and CYFRA21-1. The test results of CA125, CA15-3, CA19-9, CA72-4, AFP, CEA, NSE and CYFRA21-1 can traceable to reference measurement procedures. The age- and gender-specific RIs of the tumor markers were established. We established age- and gender-specific RIs for CA125, CA15-3, CA19-9, CA72-4, AFP, CEA, NSE and CYFRA21-1. The newly established RIs should be more suitable for Henan population. It will be valuable for clinicians to make a medical diagnosis, therapeutic management decision and other physiological assessment.  相似文献   

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