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Guillain-Barre syndrome: MR imaging findings of the spine in eight patients   总被引:4,自引:0,他引:4  
Byun  WM; Park  WK; Park  BH; Ahn  SH; Hwang  MS; Chang  JC 《Radiology》1998,208(1):137
  相似文献   
23.
朝藿素D的分离和结构   总被引:6,自引:0,他引:6  
从朝鲜淫羊藿(Epimedium koreanum)地上部分分离得到一新黄酮成分(I)和一已知化合物(II)。经光谱解析,证明I的结构为5,7,3',4'-tetrahydroxy-5'-prenylflavone,命名为朝藿素D(epimedokoreanin D);II为2-hydroxy-3,4,6,7-tetramethoxy-9,10-dihydrophenanthren。  相似文献   
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OBJECTIVE: We sought to directly compare secondhand smoke (SHS) atmospheric markers to each other and to SHS dosimetric biomarkers, permitting intercomparison of clinical and atmospheric studies. METHODS: We used atmospheric and pharmacokinetic (PK) models for the quantitative estimation of SHS exposure and dose for infants, children, and adults, based on building smoker density and air exchange rate, and from exposure duration, default PK parameters, and respiration rates. RESULTS: We estimate the SHS serum cotinine doses for the typical and most-exposed individuals in the U.S. population; predictions compare well to measurements on a national probability sample. Using default respiration rates, we estimate serum cotinine dose from SHS nicotine exposure for 40 adults exposed to SHS in an environmental chamber; predictions agreed with observations. We correlate urine cotinine and hair nicotine levels for 127 infants exposed to parental smoking, and estimate corresponding atmospheric nicotine exposure via PK modeling. CONCLUSIONS: Our "Rosetta Stone" Equations allow the SHS atmospheric markers, respirable particles, nicotine, and carbon monoxide, to be related to the SHS biomarkers, cotinine in blood, urine, and saliva and nicotine in hair, permitting intercomparison of clinical and atmospheric studies of SHS for the first time.  相似文献   
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Curcumin, derived from the rhizome curcuma longa, is one of the primary ingredients in turmeric and curry powders that are used as spices in Middle Eastern and Asian countries, especially on the Indian subcontinent. More recently, laboratory studies have demonstrated that dietary curcumin exhibits various biological activities and significantly inhibits colon tumorigenesis and tumor size in animals. Curcumin displays both anti-inflammatory and antioxidant properties, giving it the potential to be considered in the development of cancer preventive strategies and applications in clinical research. Experimental studies have shown the biological activities of the compound, but much more information on pharmacokinetics, bioavailability, and food content are needed. Whether the amount of curcumin in turmeric and curry powders is sufficient to suggest effects on biological activities and cancer risk is unknown. To determine and compare the quantitative amounts of curcumin that are present in several brands of turmeric and curry powders, a high performance liquid chromatography technique was used to analyze 28 spice products described as turmeric or curry powders and two negative controls. Pure turmeric powder had the highest curcumin concentration, averaging 3.14% by weight. The curry powder samples, with one exception, had relatively small amounts of curcumin present, and the variability in content was great. The curcumin content of these seasoning products that are consumed as a component of the diet should be considered in evaluating baseline tissue concentration and response to curcumin supplementation, which is under study in chemoprevention trials.  相似文献   
28.

Background

Statin can induce the gene expression of bone morphogenetic protein-2. Red yeast rice (RYR, Hongqu), i.e. rice fermented with Monascus purpureus, contains a natural form of statin. This study demonstrates the effects of RYR extract on bone formation.

Methods

Bone defects were created in the parietal bones of two New Zealand white rabbits. In the test animal, two defects were grafted with collagen matrix mixed with RYR extract. In the control animal, two defects were grafted with collagen matrix alone. UMR 106 cell line was used to test RYR extract in vitro. In the control group, cells were cultured for three durations (24 hours, 48 hours and 72 hours) without any intervention. In the RYR group, cells were cultured for the same durations with various concentrations of RYR extract (0.001 g/ml, 0.005 g/ml and 0.01 g/ml). Bicinchoninic acid (BCA) assay, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and alkaline phosphatase (ALP) assay were performed to measure total protein, mitochondrial activity and bone cell formation respectively.

Results

The test animal showed more formation of new bone in the defects than the control animal. RYR significantly increased the optical density in the MTT assay and ALP activity in vitro.

Conclusion

RYR extract stimulated new bone formation in bone defects in vivo and increased bone cell formation in vitro.  相似文献   
29.

Refugee populations are at high risk of experiencing trauma and developing negative mental health outcomes. The resilience of Syrian refugee children is not well established as far as modifying the association between trauma and mental illness. A total of 339 Syrian refugee children aged 10 to 17 were surveyed to assess resilience, depression and history of trauma. All children reported exposure to at least one traumatic event, 48.6% reported exposure to highly salient traumatic events such as being held hostage, kidnapping or imprisonment. High rates of suicidal ideation and depression symptomatology were found. Resilience was strongly inversely related to depression. Relational support was found to be the most protective resilience factor and was the most highly correlated with less depressive symptomatology. Empowering children and families to build resilience through social support may be a viable prevention and management approach to other unaffordable or unavailable treatments for mental illnesses.

  相似文献   
30.
Aims. Small encephaloceles of the anterior temporal pole have been increasingly recognised as an underlying epileptogenic substrate in patients with medically refractory epilepsy. The current report aims to expand on the current knowledge by emphasising that seizure semiology in such patients can vary significantly. Methods. Patients were selected from an epilepsy surgery database between 2012 and 2017. Results. Of the 143 patients who underwent epilepsy surgery, six patients had a temporal encephalocele. Four of these patients had stereo-EEG implantation. Of the four patients studied, each had a seizure semiology discordant with an ictal focus in the temporal lobe. Intracranial EEG assessment demonstrated, irrespective of this semiology, seizures originated from the anterior temporal pole. Seizures were observed to rapidly propagate to the orbitofrontal cortex, insula, temporo-occipital junction, and posterior language regions. Engagement of the mesial temporal structures could occur early or late, however, a good surgical outcome was achieved following a focused lesionectomy in either situation. Conclusion. The major finding was that seizures arising from anterior temporal encephaloceles can have an extra-temporal semiology. The varied clinical semiology and the rapid propagation to seemingly distant cortical regions could be explained by the connectivity of the anterior temporal lobe.  相似文献   
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