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11.
Abstract: Haemoptysis in otherwise healthy children is an uncommon event. Two cases of massive haemoptysis, subsequently requiring lobectomy, are discussed. In each case, foreign vegetable matter was identified despite previously normal bronchoscopy and minimal changes on chest radiograph. 相似文献
12.
Non-invasive detection of fecal protein kinase C betaII and zeta messenger RNA: putative biomarkers for colon cancer 总被引:2,自引:0,他引:2
Davidson LA; Aymond CM; Jiang YH; Turner ND; Lupton JR; Chapkin RS 《Carcinogenesis》1998,19(2):253-257
We have developed a non-invasive method utilizing feces, containing
sloughed colonocytes, as a sensitive technique for detecting diagnostic
colonic biomarkers. In this study, we used the rat colon carcinogenesis
model to determine if changes in fecal protein kinase C (PKC) expression
have predictive value in monitoring the neoplastic process. Weanling rats
were injected with saline or azoxymethane (AOM) and 36 weeks later fecal
samples and mucosa were collected, poly A+ RNA isolated, and quantitative
RT-PCR performed using primers to PKC betaII and zeta. Fecal PKC betaII and
zeta mRNA levels were altered by the presence of a tumor, with
tumor-bearing animals having a 3-fold higher (P < 0.05) PKC betaII
expression as compared with animals without tumors. In addition,
AOM-injection increased mucosal PKC betaII mRNA expression compared with
saline controls. No effect of tumor incidence on mucosal PKC betaII
expression was observed. In contrast, fecal PKC zeta expression was
2.5-fold lower (P < 0.05) in animals injected with azoxymethane versus
saline. Since tumor incidence exerts a reciprocal effect on fecal PKC
betaII and zeta mRNA expression, data were also expressed as the ratio
between PKC betaII and zeta. The isozyme ratio was strongly related to
tumor incidence, i.e. ratio for animals with tumors was 2.18 +/- 1.25,
animals without tumors was 0.50 +/- 0.16, P = 0.025. We demonstrate that
the expression of fecal PKC betaII and zeta may serve as a noninvasive
marker for development of colon tumors. A sensitive technique for the
detection of colon cancer is of importance since early diagnosis can
substantially reduce mortality.
相似文献
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Due to a scarcity of available skeletal material, anthropologists and other practitioners face difficulties with either the creation or validation of techniques used to estimate a biological profile in subadults. To address this problem, radiographic images of living individuals are often used in lieu of dry skeletal elements. However, radiographic images suffer from distortion. Some problems with metric analyses when using radiographic images may be addressed with the Lodox Statscan, an X‐ray machine that claims to produce minimal distortion along the scan‐axis due to a linear slot‐scanning design. The purpose of this research was to measure the distortion of skeletal elements in radiographic images generated from a Lodox Statscan. Skeletal elements subject to multiple imaging variables that affect distortion were radiographed, measured, and then compared to the dry bone measurements through multiple approaches. An 85% percent agreement within a ±1 mm range and a 97% agreement within a ±2 mm range was obtained. Percent difference results demonstrate that slot‐axis measurements incurred more distortion than scan‐axis measurements (11.8% and 2.7%, respectively). Inclusion of foam results in 4.5% more error than when foam is not included in the image. Angled scan‐axis measurements also incurred more distortion than either nonangled slot‐ and scan‐axis measurements. A Bland‐Altmanplot reveals an overall agreement between the radiographic and dry bonemeasurements, with most measurements falling within the upper and lower limits. Similar measurement error is found in Statscan radiographic and dry bone measurements; therefore, the Statscan offers a radiographic venue to collect metric data. Clin. Anat. 26:780–786, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
15.
The impact of research education on student nurse attitude,skill and uptake of evidence‐based practice: a descriptive longitudinal survey 下载免费PDF全文
Matthew J Leach RN BN ND DipClinNutr PhD Anne Hofmeyer RN DipUnivTeach MPHC PhD Amanda Bobridge RN BN BHSc PhD 《Journal of clinical nursing》2016,25(1-2):194-203
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17.
CJ Stewart ECL Marrs S Magorrian A Nelson C Lanyon JD Perry ND Embleton SP Cummings JE Berrington 《Acta paediatrica (Oslo, Norway : 1992)》2012,101(11):1121-1127
Aim: To describe gut colonization in preterm infants using standard culture and 16S gene rRNA profiling, exploring differences in healthy infants and those who developed NEC/late onset sepsis (LOS). Methods: Ninety‐nine stools from 38 infants of median 27‐week gestation were cultured; 44 stools from 27 infants had their microbial profiles determined by 16S. Ordination analyses explored effects of patient variables on gut communities. Results: Standard microbiological culture identified a mean of two organisms (range 0–7), DGGE 12 (range 3–18) per patient. Enterococcus faecalis and coagulase negative staphylococci (CONS) were most common by culture (40% and 39% of specimens). Meconium was not sterile. No fungi were cultured. Bacterial community structures in infants with NEC and LOS differed from healthy infants. Infants who developed NEC carried more CONS (45% vs 30%) and less Enterococcus faecalis (31% vs 57%). 16S identified Enterobacter and Staphylococcus presence associated with NEC/LOS, respectively. Conclusions: Important differences were found in the gut microbiota of preterm infants who develop NEC/LOS. The relationship of these changes to current practices in neonatal intensive care requires further exploration. 相似文献
18.
Robert E. Boykin Justin D. Stull J. Erik Giphart Coen A. Wijdicks Marc J. Philippon 《Knee surgery, sports traumatology, arthroscopy》2013,21(5):1203-1211
Presented is the case of a 25-year-old professional soccer player with a long-standing history of hip injuries, including a hamstring injury, adductor partial tearing with surgical release and labral tearing in the hip joint. The patient was eventually found to have a mixed type femoracetabular impingement and adaptive bony changes of the hip. The patient was treated with an arthroscopic acetabuloplasty of the pincer lesion, femoroplasty for the treatment of the cam lesion and labral repair along with open proximal adductor repair to restore the native biomechanics of the hip. Level of evidence V. 相似文献
19.
Functional muscle ischemia in neuronal nitric oxide synthase-deficient skeletal muscle of children with Duchenne muscular dystrophy 总被引:1,自引:0,他引:1 下载免费PDF全文
Sander M Chavoshan B Harris SA Iannaccone ST Stull JT Thomas GD Victor RG 《Proceedings of the National Academy of Sciences of the United States of America》2000,97(25):13818-13823
Duchenne muscular dystrophy (DMD) is a fatal disease caused by mutation of the gene encoding the cytoskeletal protein dystrophin. Despite a wealth of recent information about the molecular basis of DMD, effective treatment for this disease does not exist because the mechanism by which dystrophin deficiency produces the clinical phenotype is unknown. In both mouse and human skeletal muscle, dystrophin deficiency results in loss of neuronal nitric oxide synthase, which normally is localized to the sarcolemma as part of the dystrophin-glycoprotein complex. Recent studies in mice suggest that skeletal muscle-derived nitric oxide may play a key role in the regulation of blood flow within exercising skeletal muscle by blunting the vasoconstrictor response to alpha-adrenergic receptor activation. Here we report that this protective mechanism is defective in children with DMD, because the vasoconstrictor response (measured as a decrease in muscle oxygenation) to reflex sympathetic activation was not blunted during exercise of the dystrophic muscles. In contrast, this protective mechanism is intact in healthy children and those with polymyositis or limb-girdle muscular dystrophy, muscle diseases that do not result in loss of neuronal nitric oxide synthase. This clinical investigation suggests that unopposed sympathetic vasoconstriction in exercising human skeletal muscle may constitute a heretofore unappreciated vascular mechanism contributing to the pathogenesis of DMD. 相似文献
20.
Myosin light chain kinase and myosin phosphorylation effect frequency-dependent potentiation of skeletal muscle contraction 总被引:1,自引:0,他引:1 下载免费PDF全文
Zhi G Ryder JW Huang J Ding P Chen Y Zhao Y Kamm KE Stull JT 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(48):17519-17524
Repetitive stimulation potentiates contractile tension of fast-twitch skeletal muscle. We examined the role of myosin regulatory light chain (RLC) phosphorylation in this physiological response by ablating Ca(2+)/calmodulin-dependent skeletal muscle myosin light chain kinase (MLCK) gene expression. Western blot and quantitative-PCR showed that MLCK is expressed predominantly in fast-twitch skeletal muscle fibers with insignificant amounts in heart and smooth muscle. In contrast, smooth muscle MLCK had a more ubiquitous tissue distribution, with the greatest expression observed in smooth muscle tissue. Ablation of the MYLK2 gene in mice resulted in loss of skeletal muscle MLCK expression, with no change in smooth muscle MLCK expression. In isolated fast-twitch skeletal muscles from these knockout mice, there was no significant increase in RLC phosphorylation in response to repetitive electrical stimulation. Furthermore, isometric twitch-tension potentiation after a brief tetanus (posttetanic twitch potentiation) or low-frequency twitch potentiation (staircase) was attenuated relative to responses in muscles from wild-type mice. Interestingly, the site of phosphorylation of the small amount of monophosphorylated RLC in the knockout mice was the same site phosphorylated by MLCK, indicating a potential alternative signaling pathway affecting contractile potentiation. Loss of skeletal muscle MLCK expression had no effect on cardiac RLC phosphorylation. These results identify myosin light chain phosphorylation by the dedicated skeletal muscle Ca(2+)/calmodulin-dependent MLCK as a primary biochemical mechanism for tension potentiation due to repetitive stimulation in fast-twitch skeletal muscle. 相似文献