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In a prospective, randomized multicenter trial, 175 patients with abdominal aortic aneurysms were treated by conventional operation. Two types of polyester prostheses (Gelsoft Plus, Vascute Terumo Corp., Hamburg, Germany or Microvel, Boston Scientific, Ratingen, Germany) were selected randomly for implantation. Diameters ranged from 14 to 20 mm. The diameters of the grafts were measured by ultrasound postoperatively, as well as 6, 12, and 24 months after operation. Local and systemic complications were recorded. Dilation of the main body of the “Gelsoft plus” prosthesis was 19% within the first 12 months and 30% for the Microvel prosthesis. Extreme dilation was not observed. Thus, vascular prostheses must be chosen small enough and the dilation of 20–30% should be considered. The most frequent complication was incisional hernia (32%).  相似文献   
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Eight healthy adults and 48 infants 2 and 4 months old were immunized with Haemophilus influenzae type b-Neisseria meningitidis outer membrane protein complex conjugate vaccine (PRP-OMP) to evaluate antibody kinetics in the first days after immunization. Five adults (63%) had some decrease in antibody, although the geometric mean did not decrease significantly. With one exception, the nadir occurred on postimmunization day 3. Seven had an antibody increase by day 7. Of the children, 6 (75%) of 8 and 17 (77%) of 23 had a decrease in antibody in serum obtained on day 2-3 after the first or second dose, respectively, the magnitude of which directly correlated with the preimmunization antibody concentration. However, the geometric mean did not decrease significantly. Within 1 week of immunization, 85% of infants had an increase in antibody, significantly greater after the second dose than after the first. A high concentration of maternally derived antibody before immunization correlated negatively with antibody response. Thus, a transient decrease in antibody occurs in most adults and infants 2-3 days after immunization with PRP-OMP followed by a prompt increase by day 7.  相似文献   
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Administration of theophylline to asthmatic children is frequently associated with an adverse influence on their behavior. The efficacy and behavioral effects of the administration of high-dose theophylline (T) and ketotifen (K) in various combinations were evaluated prospectively in a double-blind, placebo controlled study in 55 children with moderately severe perennial asthma. During a baseline period of 2 weeks, theophylline (serum level of 10-20 μg/ml) was administered to all the children. After this period the patients were randomly allocated into four comparable groups. The children were treated during a 12-week period with: T + K-Placebo (T group); T + K (T + K group); half-dose T + K (T/ 2 + K group); or placebo of both T and K (P group). During the 12-week treatment period, as compared to the baseline period, only the three groups of children who received active therapy (T + P, T + K, T/2 + K) showed a similar reduction in the number of days with asthmatic symptomatology, improvement of the total asthmatic symptoms score, and increased PEFR. The behavioral activity of the children (assessed by the Conner's rating scale) improved significantly only in the groups receiving placebo or T/2 + K. The results of this study suggest that a combination therapy of half the recommended therapeutic dose of theophylline with ketotifen can be clinically as effective as therapy with a full dose of theophylline, but with significantly less adverse behavioral effects.  相似文献   
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BACKGROUND: Unsupervised fuzzy clustering (UFC) analysis is a mathematical technique that groups together objects in the multidimensional feature space according to a specified similarity measurement, thereby yielding clusters of similar data points that can be represented by a set of prototypes or centroids. METHODS: Since clinical studies of mental disorders distinguish between affected and unaffected individuals, we designed an inclusion/exclusion criteria (cutoff behavioral criteria [CBC]) approach for animal behavioral studies. The effect of classifying the study population into clearly affected versus clearly unaffected individuals according to behaviors on two behavioral paradigms was statistically significant. RESULTS: Here the raw data from previous studies were subjected to UFC algorithms as a means of objectively testing the validity of the concept of the CBC for our experimental model. The first UFC algorithm yielded two clearly discrete clusters, found to consist almost exclusively of the exposed animals in the one and unexposed animals in the other. The second algorithm yielded three clusters corresponding to animals designated as clearly affected, partially affected, and clearly unaffected. The algorithm for physiological data in addition to behavioral data failed to elicit discrete clusters. CONCLUSIONS: The UFC analysis yielded data that support the conceptual contention of the CBC and lends additional validity to our previous behavioral studies.  相似文献   
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Autism is a complex genetic disorder. Chromosome 15 is of particular interest in this disorder, because of previous reports of individuals with autism with chromosomal abnormalities in the 15q11-q13 region. Transmission disequilibrium between polymorphisms in this region and autism has been also been reported in some, but not all studies. Recently, a novel maternally expressed gene, ATP10C, was characterized and mapped to the chromosome 15q11-q13 region, 200 kb distal to UBE3A. It encodes a putative aminophospholipid translocase likely to be involved in the asymmetric distribution of proteins in the cell membrane. Preferential maternal expression has been demonstrated in fibroblasts and brain. Because of its physical location and imprinting pattern, ATP10C was considered to be a candidate gene for chromosome 15-associated autism. In an effort to find the genes responsible for autism in this chromosomal region, 1.5 kb of the 5' flanking region, as well as the coding and splicing regions of ATP10C, were screened for sequence variants. Several polymorphic markers including five nonsynonymous SNPs were identified. To investigate transmission disequilibrium between ATP10C and autism, a family-based association study was conducted for 14 markers in 115 autism trios. No significant transmission disequilibrium was found, suggesting ATP10C is unlikely to contribute strongly to susceptibility to autism in these families. However, due to limited power to detect genes of modest effect, the possible functional role of the nonsynonymous SNPs and the functional implications of the SNPs identified from 5' flanking region and intron 2 splicing region may be evaluated in further studies.  相似文献   
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