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1.
A van Middelkoop J E van Wyk H G Küstner I Windsor C Vinsen B D Schoub S Johnson J M McAnerney 《Transactions of the Royal Society of Tropical Medicine and Hygiene》1992,86(1):80-82
An epidemic of type 1 poliomyelitis occurred in Natal/KwaZulu in the eastern part of South Africa between December 1987 and November 1988. 412 poliomyelitis cases were reported, of whom 74% were younger than 5 years. The case-fatality rate was 8%. It is suggested that massive floods, experienced in the area 2 months earlier, triggered the outbreak. 相似文献
2.
Rupture of the distal biceps tendon: evaluation with MR imaging 总被引:2,自引:0,他引:2
3.
Neeltje A. Coolen MSc ; Marcel Vlig BAs ; Antoon J. van den Bogaerdt PhD ; Esther Middelkoop PhD ; Magda M. W. Ulrich PhD 《Wound repair and regeneration》2008,16(4):559-567
Healing of a deeper burn wound is a complex process that often leads to scar formation. Skin wound model systems are important for the development of treatments preventing scarring. The aim of this study is to develop a standardized in vitro burn wound model that resembles the in vivo situation. A burn wound (10 × 2 mm) was made in ex vivo skin and the skin samples were cultured at the air–liquid interface for 7, 14, and 21 days. Cells in the skin biopsies maintained their viability during the 21-day culture period. During culture, reepithelialization of the wound took place from the surrounding tissue and fibroblasts migrated into the wound area. Cells of the epithelial tongue and fibroblasts near the wound margin were proliferating. During culture, skin-derived antileukoproteinase and keratin 17 were expressed only in the epithelial tongue. Both collagen type IV and laminin were present underneath the newly formed epidermis, indicating that the basement membrane was restored. These results show that the burn wound model has many similarities to in vivo wound healing. This burn wound model may be useful to study different aspects of wound healing and testing pharmaceuticals and cosmetics on, e.g., migration and reepithelialization. 相似文献
4.
Androgen receptor YAC transgenic mice carrying CAG 45 alleles show trinucleotide repeat instability 总被引:1,自引:15,他引:1
La Spada AR; Peterson KR; Meadows SA; McClain ME; Jeng G; Chmelar RS; Haugen HA; Chen K; Singer MJ; Moore D; Trask BJ; Fischbeck KH; Clegg CH; McKnight GS 《Human molecular genetics》1998,7(6):959-967
X-linked spinal and bulbar muscular atrophy (SBMA) is caused by a CAG
repeat expansion in the first exon of the androgen receptor (AR) gene.
Disease-associated alleles (37-66 CAGs) change in length when transmitted
from parents to offspring, with a significantly greater tendency to shift
size when inherited paternally. As transgenic mice carrying human AR cDNAs
with 45 and 66 CAG repeats do not display repeat instability, we attempted
to model trinucleotide repeat instability by generating transgenic mice
with yeast artificial chromosomes (YACs) carrying AR CAG repeat expansions
in their genomic context. Studies of independent lines of AR YAC transgenic
mice with CAG 45 alleles reveal intergenerational instability at an overall
rate of approximately 10%. We also find that the 45 CAG repeat tracts are
significantly more unstable with maternal transmission and as the
transmitting mother ages. Of all the CAG/CTG repeat transgenic mice
produced to date the AR YAC CAG 45 mice are unstable with the smallest
trinucleotide repeat mutations, suggesting that the length threshold for
repeat instability in the mouse may be lowered by including the appropriate
flanking human DNA sequences. By sequence-tagged site content analysis and
long range mapping we determined that one unstable transgenic line has
integrated an approximately 70 kb segment of the AR locus due to
fragmentation of the AR YAC. Identification of the cis - acting elements
that permit CAG tract instability and the trans -acting factors that
modulate repeat instability in the AR YAC CAG 45 mice may provide insights
into the molecular basis of trinucleotide repeat instability in humans.
相似文献
5.
6.
It is well recognized that the ability to cryopreserve unfertilizedhuman oocytes would make a significant contribution to infertilitytreatment. However, despite considerable interest, very fewsuccessful pregnancies have arisen from cryopreserved oocytesafter thawing, insemination and transfer of the subsequent embryo.The reasons for this lack of progress may well result from adearth of information on how the various biophysical changesduring a cryopreservation regimen affect human oocyte function.Recently, fundamental studies on the effects of cooling, membranepermeability, cryoprotectant addition and ice formation havebeen performed on human oocytes by a number of groups, and theseform the basis of the current review. It is likely that successfulhuman oocyte cryopreservation will only follow once these factorsare fully understood, but the existing base of knowledge shouldprovide a platform for further improvements in the techniquescurrently employed. 相似文献
7.
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9.
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
10.
Marleen M. van den Heuvel Edwin H.G. Oei Jeroen J.M. Renkens Sita M.A. Bierma-Zeinstra Marienke van Middelkoop 《The spine journal》2021,21(3):465-476
BACKGROUND CONTEXTSeveral spinal abnormalities have been studied using magnetic resonance imaging (MRI). However, in children these studies were sparsely performed in general populations. Examining young children's spines is important since the shape of the bone is largely determined during the growth spurt. Furthermore, it is so far unknown if associations between weight status and spinal abnormalities, which are known for adolescents and adults, are already present in young children.PURPOSEWe aimed to present the prevalence of structural abnormalities in the prepubertal pediatric spine on MRI and their association with measures of the children's body weight and body composition.STUDY DESIGNCross-sectional study embedded in a prospective population-based birth cohort study.PATIENT SAMPLEFor this study, participants from the Generation R Study were selected based on the availability of MRI data of the lumbar spine and accelerometry data at the age of 9 years.OUTCOME MEASURESThe presence of structural abnormalities of intervertebral discs and vertebrae was scored on MRI. The body mass index-standard deviation [BMI-SD] score was calculated from objectively measured weight and height, and body composition measurements were obtained by a dual-energy X-ray absorptiometry scan.METHODSA semiquantitative scoring tool to assess the intervertebral discs and vertebrae of the lumbar spine on conventional MRI was designed for this purpose. Proportions of children with spinal abnormalities on at least one lumbar vertebral level were presented. Logistic regression was used to analyze associations between abnormalities and weight and body composition. We declare not to have any financial conflicts of interests.RESULTSWe included 559 children (median age of 9.88 years (interquartile range 6.74–10.02), 48.5% boys). Most frequently observed abnormalities of the intervertebral discs were abnormal signal intensity (24.9%), decreased or collapsed disc height (37.6%), disc bulging (73.3%), and abnormal nuclear shape (29.1%). Vertebral endplate irregularities and lumbosacral transitional vertebrae were seen in respectively 40% and 9.3% of the participants. Except for disc bulging, all abnormalities were predominantly present at the L5 level. Only the presence of endplate irregularities was associated with a higher body weight (BMI SD score (odds ratio [OR] 1.50 [95% confidence interval [CI] 1.21–1.86]) and BMI SD change (OR 1.48 [95% CI 1.07–2.03])) and increased body mass values in body composition measurements (% body fat (OR 1.05 [95% CI 1.02–1.09), fat mass index (OR 1.23 [95% CI 1.09–1.39]), and fat-free mass index (OR 1.30 [95% CI 1.06–1.59])) in adjusted analyses.CONCLUSIONSStructural spinal abnormalities, especially disc bulging, endplate irregularities, and an abnormal disc height, are already present in children aged 9 years from a Dutch population-based cohort. Of those abnormalities, endplate irregularities are associated with various weight and body composition measurements. 相似文献