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131.
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A method is described for the densitometric determination of the p-hydroxybenzoic esters and p-hydroxybenzoic acid in mixtures or in drugs. This method is compared with the one used in high performance liquid chromatography (HPLC). The calibration curves were linear in interval 0.250-3.60 mumol ml-1 per 200 nl per spot. The limit of detection and the relative standard deviation (RSD) are higher than in HPLC (RSD is 6% in HPTLC. 3% in HPLC; limit of detection about 40 pmol in HPTLC and 25 pmol in HPLC) but HPTLC quantitative determination of parabens in drugs is faster.  相似文献   
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BACKGROUND: Few references exist regarding contemporary complications of pyloromyotomy (PM) for infantile hypertrophic pyloric stenosis (IHPS). Therefore, we reviewed the frequency and outcome of patients with IHPS who developed complications from PM. METHOD: A 25-year retrospective review was performed in two populations. The first group included all infants who had a PM for IHPS at two pediatric surgery centers. The second group included all infants referred from other institutions who developed complications following PM for IHPS. RESULTS: Between 1969 and 1994, 901 PMs were performed. Intraoperative complications occurred in 40 patients (4%), including 39 duodenal perforations and 1 difficult intubation requiring prolonged ventilation. No unrecognized duodenal perforations or incomplete PMs were found. Postoperative complications developed in 52 patients (6%). The wound infection rate was less than 1%. Postoperative vomiting occurred in 31 infants (3%). The mortality rate was 0.1%, with 1 death due to sepsis from delayed diagnosis of Hirschsprung's disease. During the same study period, 11 patients were referred from other hospitals for postoperative complications. Five had persistent vomiting treated successfully with expectant management. Six infants needed reoperation: 3 for persistent IHPS, 1 for gastric outlet obstruction, and 1 for small bowel obstruction secondary to adhesions; 1 required wound abscess drainage. CONCLUSION: Pyloromyotomy is not without complications. Duodenal perforation should be infrequent, but when it occurs, it can usually be readily recognized and treated with minimal morbidity. Postoperative vomiting can be managed nonoperatively, but if it persists longer than 5 days, radiologic evaluation should be performed. Incomplete PM is uncommon and should not occur. A second myotomy is needed when the diagnosis of incomplete myotomy is established. A single standard of care should be expected of all surgeons who perform PM for IHPS.  相似文献   
135.
A microsatellite map of wheat   总被引:1,自引:0,他引:1  
Hexaploid bread wheat (Triticum aestivum L. em. Thell) is one of the world's most important crop plants and displays a very low level of intraspecific polymorphism. We report the development of highly polymorphic microsatellite markers using procedures optimized for the large wheat genome. The isolation of microsatellite-containing clones from hypomethylated regions of the wheat genome increased the proportion of useful markers almost twofold. The majority (80%) of primer sets developed are genome-specific and detect only a single locus in one of the three genomes of bread wheat (A, B, or D). Only 20% of the markers detect more than one locus. A total of 279 loci amplified by 230 primer sets were placed onto a genetic framework map composed of RFLPs previously mapped in the reference population of the International Triticeae Mapping Initiative (ITMI) Opata 85 x W7984. Sixty-five microsatellites were mapped at a LOD >2.5, and 214 microsatellites were assigned to the most likely intervals. Ninety-three loci were mapped to the A genome, 115 to the B genome, and 71 to the D genome. The markers are randomly distributed along the linkage map, with clustering in several centromeric regions.  相似文献   
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Melanocyte lineage-specific antigens, such as gp100, have been shown to induce both cellular and humoral immune responses against melanoma. Therefore, these antigens are potential targets for specific antimelanoma immunotherapy. A novel approach to induce both cellular and humoral immunity is genetic vaccination, the injection of antigen-encoding naked plasmid DNA. In a mouse model, we investigated whether genetic vaccination against the human gp100 antigen results in specific antitumor immunity. The results demonstrate that vaccinated mice were protected against a lethal challenge with syngeneic B16 melanoma-expressing human gp100, but not control-transfected B16. Both cytotoxic T cells and IgG specific for human gp100 could be detected in human gp100-vaccinated mice. However, only adoptive transfer of spleen-derived lymphocytes, not of the serum, isolated from protected mice was able to transfer antitumor immunity to nonvaccinated recipients, indicating that CTLs are the predominant effector cells. CTI, lines generated from human gp100-vaccinated mice specifically recognized human gp100. Interestingly, one of the CTL lines cross-reacted between human and mouse gp100, indicating the recognition of a conserved epitope. However, these CTLs did not appear to be involved in the observed tumor protection. Collectively, our results indicate that genetic vaccination can result in a potent antitumor response in vivo and constitutes a potential immunotherapeutic strategy to fight cancer.  相似文献   
138.
The objective of this study was to evaluate the potential of Fourier transform infrared spectroscopy (FTIR) for rapid identification of Bacillus cereus isolates. Ten B. cereus group isolates (comprising B. cereus, Bacillus mycoides, and Bacillus thuringiensis strains), five other Bacillus spp., and five non-Bacillus spp. were used. Two types of media, brain heart infusion (BHI) and Trypticase soy agar (TSA), were tested. The results indicated that all B. cereus group isolates produced characteristic absorbance peaks at wave numbers between 1738 and 1740 cm-1. These peaks were not affected by the growth medium. None of the other bacteria tested showed a similar peak after growth on BHI or TSA. Absorbance peaks between 1800 and 1500 cm-1 of members of the B. cereus group had different shapes and sizes, suggesting that FTIR may be useful for rapid identification of species within the B. cereus group.  相似文献   
139.
The SLT2(MPK1) mitogen-activated protein kinase signal transduction pa thway has been implicated in several biological processes in Saccharomyces cerevisiae, including the regulation of cytoskeletal and cell wall structure, polarized cell growth, and response to nutrient availability, hypo-osmotic shock and heat shock. We examined the conditions under which the SLT2 pathway is activated. We found that the SLT2 kinase is tyrosine phosphorylated and activated during periods in which yeast cells are undergoing polarized cell growth, namely during bud formation of vegetative cell division and during projection formation upon treatment with mating pheromone. BCK1(SLK1), a MEK kinase, is required for SLT2 activation in both of these situations. Upstream of BCK1(SLK1), we found that the STE20 kinase was required for SLT2 activation by mating pheromone, but was unnecessary for its activation during the vegetative cell cycle. Finally, SLT2 activation during vegetative growth was partially dependent on CDC28 in that the stimulation of SLT2 tyrosine phosphorylation was significantly reduced directly after a temperature shift in cdc28 ts mutants. Our data are consistent with a role for SLT2 in promoting polarized cell growth.  相似文献   
140.
Acute hypoglycemia in people with type 1 (insulin-dependent) diabetes mellitus causes general impairment in cognitive performance. The effects on more specific cognitive processes are less well defined. Acute hypoglycemia has been shown to impair visual information processing in nondiabetic human subjects and has now been examined in 16 adult subjects with type 1 diabetes. All subjects had normal visual acuity and no diabetic retinopathy, and their median (range) age was 24 (18-47) years with a median (range) duration of type 1 diabetes of 8 (2-18) years and a mean (SD) HbA1c of 8.5 (1.3)%. A hyperinsulinemic glucose clamp technique was used to maintain arterialized blood glucose at 5.0 mmol l(-1), and on separate test days, either euglycemia was continued or hypoglycemia (2.6 mmol l(-1)) was induced. During each condition subjects performed tests of visual processing and cognitive function. Hypoglycemia caused a significant disruption in general cognitive ability as assessed by digit symbol (p < 0.001) and trail-making B (p < 0.05) tasks. Conventional measures of visual acuity were unaffected by hypoglycemia, but visual information processing deteriorated significantly as indexed by inspection time (p < 0.005) and visual change detection (p < 0.01). Contrast sensitivity tended to deteriorate during hypoglycemia (p = 0.06). In conclusion, hypoglycemia impairs important aspects of early visual information processing and contrast sensitivity in adults with type 1 diabetes. Further research is needed to evaluate the functional relevance of such changes for everyday tasks that require the intake of visual information at speed and under conditions of low contrast.  相似文献   
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