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11.
Using a newly devised 50-channel photometer which records the opacity of growing bacterial cultures, it was shown that the time taken by cultures diluted 1/1000 in fresh broth to reach 50% of the opacity of a fully grown culture was inversely related to the concentration of organisms in the original culture. This relation was used to determine the numbers of survivors after exposure to benzylpenicillin and gentamicin alone and in combination. The procedure is commended as a labour-saving and potentially rapid method of obtaining comprehensive information on the bactericidal action and interaction of antibiotics. 相似文献
12.
Carol A Mathews Caroline M Nievergelt Amin Azzam Helena Garrido Denise A Chavira Jennifer Wessel Monica Bagnarello Victor I Reus Nicholas J Schork 《American journal of medical genetics. Part B, Neuropsychiatric genetics》2007,(2):174-182
To date, only one complete genome screen for obsessive-compulsive disorder (OCD) has been published. That study identified a region of suggestive linkage (maximum lod score of 2.25) with a relatively small sample size (N = 56; 27 with OCD). Additional complete genome screens are needed to confirm this finding and identify other regions of linkage. We present the clinical characteristics and power to detect linkage of 11 multigenerational families with OCD and hoarding (N = 92; 44 with OCD), as well as heritability estimates for several quantitative traits. Families with at least two individuals with OCD were identified through probands with childhood-onset OCD. Expected lod scores were calculated for simulated genetic marker data under an additive and two dominant models assuming a dense SNP marker map. All affected individuals had an early age of onset (18 or younger). Hoarding was present in 46% of subjects. Obsessive-compulsive symptoms and hoarding were highly heritable. The maximum mean expected lod score was 3.31 for OCD and 1.39 for hoarding. We found reasonable power to detect regions of interest (lod = 2) for OCD in these families, but will need to expand our family collection to have adequate power to detect regions of interest for hoarding. 相似文献
13.
KM Kanal NJ Hangiandreou AM Sykes HE Eklund PA Araoz JA Leon BJ Erickson 《Journal of digital imaging》2002,14(1):30-37
The aims of this work were to measure the accuracy of one continuous speech recognition product and dependence on the speaker's
gender and status as a native or nonnative English speaker, and evaluate the product's potential for routine use in transcribing
radiology reports. IBM MedSpeak/Radiology software, version 1.1 was evaluated by 6 speakers. Two were nonnative English speakers,
and 3 were men. Each speaker dictated a set of 12 reports. The reports included neurologic and body imaging examinations performed
with 6 different modalities. The dictated and original report texts were compared, and error rates for overall, significant,
and subtle significant errors were computed. Error rate dependence on modality, native English speaker status, and gender
were evaluated by performing ttests. The overall error rate was 10.3 +/- 3.3%. No difference in accuracy between men and women
was found; however, significant differences were seen for overall and significant errors when comparing native and nonnative
English speakers (P = .009 and P = .008, respectively). The speech recognition software is approximately 90% accurate, and
while practical implementation issues (rather than accuracy) currently limit routine use of this product throughout a radiology
practice, application in niche areas such as the emergency room currently is being pursued. This methodology provides a convenient
way to compare the initial accuracy of different speech recognition products, and changes in accuracy over time, in a detailed
and sensitive manner. 相似文献
14.
15.
E Harburg W DiFranceisco D W Webster L Gleiberman A Schork 《Journal of studies on alcohol》1990,51(3):245-256
The "fall-off" effect, when offspring respond to parental high-volume levels by moderating their own drinking, appears highly predictable across generations and is mediated both by subsequent parent drinking level and offspring's perception of problematic intake by their parents. This fall off by adult offspring appears to follow community norms; it occurs, on the average, at the level of daily drinking by fathers, and when the mother approaches daily-drinking levels. An aversion effect holds more to cross-sex parents with problems; thus, both sons and daughters show a nonimitation and fall off to their cross-sex parents who are high-volume problem drinkers. Conversely, however, daughters often imitate a high-drinking father with no problems. For high-drinking mothers, without problems or with problems (numbers are small), daughters' drinking appears "polarized": most (60%) are abstemious, but a higher number than expected (about 35%) show high volume thus imitating the mother's volume, compared to about 17% of the total sample of daughters who were high-volume drinkers. Maximal offspring imitation is strongest for abstemious parents, especially for abstaining parents, and stronger for fathers abstaining than for mothers. 相似文献
16.
17.
This study was designed to compare the growth of Pakistani schoolchildren in the UK with the 1990 UK growth standards. Measurements of height, weight, and sitting height were performed on 785 Pakistani schoolchildren aged 5-14 years with the mean values for each age and sex being plotted on the UK growth standards. The results were expressed as SD scores relative to the 1990 reference data. The mean height for the boys was only 0.2 SD scores below the mean for the new growth standards with the mean height for the girls being 0.4 SD scores below the mean. The mean values for weight and body mass index were 0.3 and 0.5 SD scores less than the mean for boys and girls respectively. This study demonstrates that the growth of Pakistani schoolchildren in the UK is comparable to the 1990 UK growth standards with only minor differences. It is not safe to assume that short stature or low body weight in a Pakistani child is due to his or her ethnic background. 相似文献
18.
The Human Genome Project will have an enormous impact on our ability to study and understand human disease by providing maps of human genes. However, many of the most prevalent human diseases result from the complex interaction of numerous genes. Even with the use of a catalogue of human genes, the task of analyzing complex genetic and environmental interactions involved in the common human disorders will be formidable. Due to its demographic specificities and large size, the Chinese population offers a unique resource for the study of human genetics and the ability to capitalize upon the recent revolution in biotechnology. Reasons that China provides an exceptional population for genetic studies of complex diseases include: (i) the resource of 1.3 billion people makes obtaining a large number of subjects with rare (and common) diseases possible; (ii) relative genetic homogeneity in many regions has been preserved; (iii) stratification is distinct; (iv) urban/rural and geograph ic contrasts, both in environmental factors and disease occurrence, are quite marked; (v) family members tend to stay congregated; and (vi) epidemiologic study is cost-beneficial. 相似文献
19.
Impact of education for physicians on patient outcomes 总被引:4,自引:0,他引:4
NM Clark M Gong MA Schork D Evans D Roloff M Hurwitz L Maiman RB Mellins 《Pediatrics》1998,101(5):831-836
20.
Comprehensive mutational scanning of the p53 coding region by two- dimensional gene scanning 总被引:2,自引:0,他引:2
A comprehensive mutational scanning test for the p53 coding region based on
multiplex PCR and two-dimensional DNA electrophoresis was designed and
evaluated. In a 2-step multiplex PCR, the p53 coding region (exons 2-11)
was amplified as a single 8646-bp fragment by long- distance PCR in step
one. This fragment served as a template for the subsequent co-amplification
of the individual exons in two multiplex groups in step two. The multiplex
products were then separated, first on the basis of size in non-denaturant
polyacrylamide gels and then on the basis of sequence by denaturing
gradient gel electrophoresis (DGGE). Primers for optimal PCR, melting
behavior and 2-D gel distribution were designed using a recently developed
computer program. The resulting two-dimensional gene scanning (TDGS) test
was evaluated by screening, in a blinded fashion, 29 coded DNA samples from
Li- Fraumeni syndrome patients with previously identified germline
mutations. All mutations were correctly detected. This assay provides an
accurate, cost-effective and non-radioactive method for simultaneous
mutational scanning of all p53 coding exons.
相似文献