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131.
OBJECTIVE: To describe several aspects of booster seat use and misuse in a sample of children attending child safety seat clinics. METHODS: Booster seat practices were assessed at 76 child safety seat clinics held between April 1997 and January 1999 in Pennsylvania and southern New Jersey. At each assessment, a child passenger safety team evaluated the booster seat and identified modes of misuse. RESULTS: Altogether 227 booster seats were observed. Sixty eight per cent (68%) of shield boosters and 20% of belt positioning boosters were misused. Thirty two per cent of the children using a shield booster weighed more than 40 lb (18.1 kg); 68% of children in shield boosters and 63% in belt positioning boosters weighed less than 40 lb. CONCLUSION: This study identified a relatively high rate of booster seat misuse. Shield boosters were more likely to be misused than belt positioning booster seats. Significant numbers of children weighing more than 40 lb were using possibly dangerous shield boosters. The majority of children in this study were less than 40 lb. In this weight range, a convertible child restraint system provides better protection than a booster seat. Booster seat use should only be initiated once the child has completely outgrown their convertible child restraint system. 相似文献
132.
We describe a case of infective endocarditis due to Moraxella lacunata involving the native mitral and aortic valves, complicated by cerebral emboli and resultant hemiparesis. The patient was treated with ceftriaxone and gentamicin and improved. This appears to be the first case reported in the medical literature of native multivalvular endocarditis produced by this rare organism. 相似文献
133.
ABSTRACT. The infant feeding pattern among 96 Turkish mothers living in a suburb of Istanbul and 30 living in a suburb of Stockholm, both with working class characteristics, was determined. The duration of breastfeeding among the Turkish immigrant group living in the Stockholm suburb was significantly reduced compared with the group with a similar social background but living in a native urban area. Infant feeding pattern among the Turkish immigrant mothers was more similar to that of Swedish populations. Attitudes to breastfeeding among the immigrant group had changed. Early weaning, reliance on commercially available infant foods and bottle feeding characterized their infant feeding practices. The majority of the infants of this group showed a tendency to overweight. 相似文献
134.
135.
Further characterization, isolation and identification of the epithelial cell-surface antigen defined by monoclonal antibody AUA1 总被引:3,自引:0,他引:3
H Durbin N Rodrigues W F Bodmer 《International journal of cancer. Journal international du cancer》1990,45(3):562-565
The human epithelial antigen recognized monoclonal antibody (MAb) AUA1 has been characterized as a cell-surface glycoprotein. It has been isolated from human colonic mucosa by AUA1 affinity separation. N-terminal peptide sequence of this purified material has revealed a 17 amino acid sequence which identifies it with one of a group of similar epithelial/tumor-associated glycoproteins defined by a variety of MAbs. Using the polymerase chain reaction to map the gene encoding this antigen, our previous AUA1 antigen assignment to chromosome 2 has been confirmed. 相似文献
136.
Gastric emptying in preterm infants. 总被引:1,自引:1,他引:0
A K Ewer G M Durbin M E Morgan I W Booth 《Archives of disease in childhood. Fetal and neonatal edition》1994,71(1):F24-F27
An ultrasonic technique was used to compare gastric emptying after a feed of expressed breast milk and formula milk in a blind, cross over study of preterm infants. Fourteen infants (median gestational age 33 weeks) were studied on 46 occasions. Each infant received a nasogastric feed of either expressed breast milk or formula milk, and the alternative at the next feed. Real time ultrasound images of the gastric antrum were obtained and measurements of antral cross sectional area (ACSA) were made before the feed and then sequentially after its completion until the ACSA returned to its prefeed value. The half emptying time (50% delta ACSA) was calculated as the time taken for the ACSA to decrease to half the maximum increment. On average, expressed breast milk emptied twice as fast as formula milk: mean 50% delta ACSA expressed breast milk 36 minutes; formula milk 72 minutes. The technique was reproducible and there was no significant difference between the emptying rates of feeds of the same type for an individual infant. These data show that breast milk has a major effect on gastric emptying, which may have important implications for preterm infants who have a feed intolerance due to delayed gastric emptying. 相似文献
137.
PURPOSE OF REVIEW: Tracheostomy is one of the most common procedures performed in the intensive care unit. Indications, risks, benefits, timing and technique of the procedure, however, remain controversial. The decision of when and how to perform a tracheostomy is often subjective, but must be individualized to the patient. The following review gives an update on recent literature related to tracheostomy in the critically ill. RECENT FINDINGS: Surprisingly, few data are available on the current practice of tracheostomy in the intensive care unit setting. Very few trials address this issue in a prospective, randomized fashion (randomized controlled trial). Most reports include small numbers representing a heterogeneous population, describing contrary results and precluding any definite conclusions. Evidence seems to suggest that early tracheostomy, however, might be preferable in selected patients. SUMMARY: Due to increased experience and advanced techniques, percutaneous tracheostomy has become a popular, relatively safe procedure in the intensive care unit. The question of appropriate timing, however, has not been definitely answered with a randomized controlled trial. Instead, a number of retrospective studies and a single prospective study have shed some light on this issue. Most reports favor the performance of tracheostomy within 10 days of respiratory failure. 相似文献
138.
Human Cytomegalovirus Inhibits Major Histocompatibility Complex Class II Expression By Disruption of the Jak/Stat Pathway 总被引:16,自引:4,他引:16
139.
Evidence of both ontogeny and transplant dose-regulated expansion of hematopoietic stem cells in vivo 总被引:3,自引:11,他引:3
Recent assessment of the long-term repopulating activity of defined subsets of hematopoietic cells has offered new insights into the characteristics of the transplantable stem cells of this system; however, as yet, there is very little known about mechanisms that regulate their self-renewal in vivo. We have now exploited the ability to quantitate these cells using the competitive repopulating unit (CRU) assay to identify the role of both intrinsic (ontological) and extrinsic (transplanted dose-related) variables that may contribute to the regulation of CRU recovery in vivo. Ly5.1 donor cells derived from day-14.5 fetal liver (FL) or the bone marrow (BM) of adult mice injected 4 days previously with 5-fluorouracil were transplanted at doses estimated to contain 10, 100, or 1,000 long-term CRU into irradiated congenic Ly5.2 adult recipient mice. Eight to 12 months after transplantation, there was a complete recovery of BM cellularity and in vitro clonogenic progenitor numbers and a nearly full recovery of day-12 colony-forming unit-spleen numbers irrespective of the number or origin of cells initially transplanted. In contrast, regeneration of Ly5.1+ donor-derived CRU was incomplete in all cases and was dependent on both the origin and dose of the transplant, with FL being markedly superior to that of adult BM. As a result, the final recovery of the adult marrow CRU compartment ranged from 15% to 62% and from 1% to 18% of the normal value in recipients of FL and adult BM transplantation, respectively, with an accompanying maximum CRU amplification of 150- fold for recipients of FL cells and 15-fold for recipients of adult BM cells. Interestingly, the extent of CRU expansion from either source was inversely related to the number of CRU transplanted. These data suggest that recovery of mature blood cell production in vivo may activate negative feedback regulatory mechanisms to prematurely limit stem cell self-renewal ability. Proviral integration analysis of mice receiving retrovirally transduced BM cells confirmed regeneration of totipotent lymphomyeloid repopulating cells and provided evidence for a greater than 300-fold clonal amplification of a single transduced stem cell. These results highlight the differential regenerative capacities of CRU from fetal and adult sources that likely reflect intrinsic, genetically defined determinants of CRU expansion but whose contribution to the magnitude of stem cell amplification ultimately obtained in vivo is also strongly influenced by the initial number of CRU transplanted. Such findings set the stage for attempts to enhance CRU regeneration by administration of agents that may enable full expression of regenerative potential or through the expression of intracellular gene products that may alter intrinsic regenerative capacity. 相似文献
140.
A novel retinal biomarker for Parkinson's disease: Quantifying the foveal pit with optical coherence tomography
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