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991.
The purpose of this study was to survey expert opinion on the management of low colony counts (< 100,000 colony forming units/mL) of asymptomatic group B streptococcus (GBS) bacteriuria discovered in the first trimester. A survey was sent to the 241 senior obstetricians affiliated with each of the Obstetrics and Gynecology training programs in the United States on July 10, 2002. Surveys received by the deadline (September 1, 2002) were included in the dataset. Eighty-five completed surveys were returned for a response rate of 35%. Seventy-seven percent reported treating low colony counts of asymptomatic GBS bacteriuria in the first trimester at the time of diagnosis, whereas 23% stated they did not treat prior to labor (margin of error 7.5% with 95% confidence). Nine percent stated that their institution had a written protocol for the treatment of low colony counts of asymptomatic GBS bacteriuria. Two physicians indicated that they screened for asymptomatic GBS bacteriuria at 28 weeks. Currently, no generally accepted protocol for the management of low colony counts of asymptomatic GBS bacteriuria exists. This survey indicates that most of the responding senior obstetricians at United States training programs treat low colony counts of asymptomatic GBS bacteriuria in the first trimester.  相似文献   
992.
Adolescents with language-based learning disabilities (LBLD) often interpret idioms literally. When idioms are provided in an enriched context, comprehension is compromised further because of the LBLD student's inability to assign multiple meanings to words, assemble and integrate information, and go beyond a local referent to derive a global, coherent meaning. This study tested the effects of context and familiarity on comprehension of 24 idioms in 22 adolescents with LBLD. The students completed the Idiom Comprehension Test (ICT) [Language, Speech, and Hearing Services in Schools 30 (1999) 141; LSHSS 34 (2003) 69] in one of two conditions: in a story or during a verification task. Within each condition were three familiarity levels: high, moderate, and low. The LBLD adolescents' data were then compared to previously collected data from 21 age-, gender-, and reading ability-matched typically developing (TD) peers. The relations between reading and language literacy and idiom comprehension were also examined in the LBLD adolescents. Results showed that: (a) the LBLD adolescents generally performed poorly relative to their TD counterparts; however, the groups performed comparably on the high and moderate familiarity idioms in the verification condition; (b) the LBLD adolescents performed significantly better in the verification condition than in the story condition; and (c) reading ability was associated with comprehension of the low familiarity idioms in the story condition only. Findings are discussed relative to implications for speech-language pathologists (SLPs) and educators working with adolescents with LBLD. LEARNING OUTCOMES: As a result of this activity, the participant will be able to (1) describe the importance of metalinguistic maturity for comprehension of idioms and other figures of speech; (2) understand the roles of context and familiarity when assessing idiom comprehension in adolescents with LBLD; and (3) critically evaluate assessments of idiom comprehension and determine their appropriateness for use with adolescents with LBLD.  相似文献   
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DNA derived from regions upstream of the Salmonella enterica serovar Typhimurium ssaG gene were used to drive expression of different reporter genes in putative Salmonella vaccine strains. Expression from ssaG was shown to be significantly upregulated once Salmonella had entered murine or human macrophages, and levels of expression were dependent on the length of the ssaG 5' sequence incorporated. S. Typhimurium derivatives harbouring the Escherichia coli heat labile toxin B subunit (LT-B) fused to various lengths of the ssaG promoter region were also constructed as single copy chromosomal integrations. Expression of LT-B by these Salmonella derivatives was detected at significant levels after intra-macrophage survival and mice immunised with these derivatives mounted marked anti-LT-B humoral antibody responses.  相似文献   
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BACKGROUND AND OBJECTIVES: The standard hematoxylin and eosin (H&E) stain can yield dramatic underestimates of tissue death when pathology is performed immediately after radiative surgery. Our objectives were to identify an accurate, consistent histology, and to understand under what conditions the problem is manifested. STUDY DESIGN/MATERIALS AND METHODS: Photothermal surgery with highly concentrated sunlight was performed ex vivo on chicken livers, and in vivo on healthy live rats that were sacrificed at periods of 0, 24, 48, and 72 hours. Pathology with both H&E and an alternative NADH-diaphorase (NADH) stain were prepared. RESULTS: H&E pathology performed shortly after surgery errs by close to an order of magnitude in appraising lesion volume, but the shortfall is mitigated when histological examination is postponed for 24 hours. The biochemical signals missed by the H&E technique at short times can be captured by the NADH stain which reveals the cessation of enzymatic activity, albeit at greater expense and complexity. CONCLUSIONS: The significance lies in avoiding false positives in surgery, providing reliable estimates of photothermal surgical efficacy, and highlighting the relative merits of alternative histological practices with photothermal surgery.  相似文献   
998.
Subramonian K  DeSylva S  Bishai P  Thompson P  Muir G 《European urology》2004,45(3):346-51; author reply 351
OBJECTIVES: A preliminary study to evaluate the feasibility of a protocol for comparing the learning curves for open and laparoscopic surgical procedures. PARTICIPANTS AND METHODS: Thirteen pre-clinical medical students with no previous surgical training were given intensive coaching in open and laparoscopic surgical techniques for 12 weeks. At the end of this period, their open and laparoscopic skills were assessed by three independent examiners. Individual and aggregate ability scores in various aspects of open and laparoscopic surgery and the time taken to perform the procedures were compared using Student's t-test. RESULTS: There was no statistically significant difference in the overall scores by the two different techniques ( p=0.057 ). However, differences between the two techniques were significant in certain criteria including tissue dissection (p=0.024), tidiness of gall bladder (p=0.034 ) and liver ( p=0.016 ) specimens and the time taken for the two techniques ( p < or = 0.001 ). CONCLUSIONS: This study suggests that when inexperienced subjects are given equal training in laparoscopy and open surgery, the overall skills acquired were similar by both methods when assessed after 6 weeks. However, on detailed analysis of the different components of surgery, the laparoscopic skills were deficient in finer dissection, identification of correct planes and two-dimensional perception when compared to open surgery and required more operative time. Our study group perceived that laparoscopy was more difficult to learn than open surgery even after the training. The study group also felt that the training in basic surgical skills during their undergraduate careers would make them more interested in studying surgery and choosing it as a career.  相似文献   
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