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101.
Strauss  EB; Sostman  HD; Gottschalk  A 《Radiology》1987,163(2):505-506
By conventional criteria, perfusion defects that correspond to radiographic parenchymal opacities of similar size have less diagnostic significance for pulmonary embolism (PE) than perfusion defects in areas that are radiographically clear, regardless of the findings on ventilation scan. It was proposed that the demonstration of normal ventilation in areas with matched radiographic opacity and perfusion defects does support the diagnosis of PE. To test this hypothesis, a retrospective review was done of selected cases from a consecutive series of 85 pulmonary angiography studies. Cases were reviewed if the following criteria were met: chest radiography, ventilation-perfusion scintigraphy, and angiography of the relevant regions had all been performed within 24 hours of one another, and there was a radiographic opacity corresponding to the perfusion defect. Sixteen cases fulfilled these criteria. Six patients had normal ventilation in the regions of the radiographic infiltrate and perfusion defect, and all had PE. No patient had an area of opacity and perfusion defect and normal ventilation without PE.  相似文献   
102.
Solubility measurements of candidate coating materials have been performed in supercritical (SC) CO(2) so as to select appropriate coating materials for implementation of a solvent-free coating process previously described. Solubility of lipidic compounds such as waxes (paraffin, beeswax, Carnauba wax), pure triglycerides (tricaprin, trimyristin, tripalmitin, tristearin) and mixture of glycerides and fatty acid esters (Gelucire) in SC CO(2) were evaluated in a static mode under different temperature and pressure conditions, ranging from 13-52 degrees C and from 50-220 bar, whether the CO(2)was in its liquid or SC state. It was shown that the compounds which are mixtures of various components give rise to a selective extraction of the lower melting point components, as evidenced from thermal analysis of soluble and insoluble fractions of the coating materials.  相似文献   
103.

Background  

This study investigated the effects of hyperoxic treatment on growth, angiogenesis, apoptosis, general morphology and gene expression in DMBA-induced rat mammary tumors.  相似文献   
104.
Exposure to estrogens is associated with an increase in cancers, including malignancies of the breast and uterus in humans, and of the kidney in hamsters. DNA damage induced by metabolic activation of estrogen has been postulated to result in gene mutations critical for the development of estrogen-induced kidney tumors in hamsters. As part of our examination of the genetic consequences of estrogen-induced DNA damage, we searched for estrogen-induced alterations in microsatellite DNA, a frequent site of mutation in tumors. Genomic DNA isolated from kidney of hamsters treated with estradiol, from estrogen-induced kidney tumors and from untreated age-matched controls, was examined by Southern blot analysis with three multi-locus oligonucleotide probes: (GACA)4, (CAC)6 and (CAG)6. Alterations in DNA fragments containing GACA and CAC tandem repeats were detected in kidney DNA of hamsters treated with hormone for 3 and 4 months, whereas no such effects were seen in control animals. In estrogen-induced tumors, microsatellite alterations were observed in fragments that contain these same two repeat sequences and also CAG repeat sequences. The induction of microsatellite alterations by estradiol in kidney DNA preceding estrogen-induced renal malignancy may play a role in hormone-induced tumorigenesis.   相似文献   
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An accidentally inhaled foreign body (A metallic toe ring) inside the larynx of a 2 1/2 year old child has been studied. It remained in the larynx for 8 months before detection and removal.  相似文献   
108.
Schoomaker  EB; Butler  WM; Diehl  LF 《Blood》1982,59(6):1213-1219
Structural membrane proteins were studied from erythrocytes (RBC) of a patient with a nonhemolytic form of hereditary elliptocytosis (HE) who developed a microcytic anemia with fragmented RBC while cobalamin (B12) deficient. Evidence is presented for qualitative changes in the patient's RBC membranes not related to a loss of structural proteins. Sensitivity of RBC to heat treatment was studied as well as quantitative changes in proteins by densitometry of 1% SDS--10% PAGE gels. Fractions of RBC of various sizes from the patient while B12 deficient all possessed a marked degree of heat sensitivity when compared to RBC from the patient after B12 repletion, normal family members, HE controls, B12-deficient controls, anemic controls, and normal controls. Because loss of spectrin (bands 1 + 2) from heat- sensitive RBC membranes in hereditary pyropoikilocytosis has been reported, the amount of spectrin relative to band 3 was measured. No decrease in the ratio of bands (1 + 2)/3 was found. In addition, no chromatographically abnormal membrane proteins were found by SDS-PAGE of the patient's RBC while B12 deficient. Our findings indicate that B12 deficiency results in an abnormal membrane with enhanced instability in some forms of HE. Since protein loss was not found, we conclude that an alteration in membrane protein interaction may be involved.  相似文献   
109.
Glioblastoma is a devastating malignancy with a dismal survival rate.Currently,there are limited prognostic markers of glioblastoma including IDH1,ATRX,MGMT,PTEN,EGFRv Ⅲ,and others.Although these biomarkers for tumor prognosis are available,a surgical biopsy must be performed for these analyses,which has morbidity involved.A non-invasive and readily available biomarker is sought after which provides clinicians prognostic information.Sodium is an electrolyte that is easily and quickly obtained through analysis of a patient's serum.Hyponatremia has been shown to have a predictive and negative prognostic indication in multiple cancer types,but the role of glioblastoma patients' serum sodium at the time of diagnosis in predicting glioblastoma patient survival has not been determined.We assessed whether hyponatremia at the time of glioblastoma diagnosis correlates to patient survival and show that in our cohort of 200 glioblastoma patients,sodium,at any level,did not significantly correlate to glioblastoma survival,unlike what is seen in multiple other cancer types.We further demonstrate that inducing hyponatremia in an orthotopic murine model of glioblastoma has no effects on tumor progression and survival.  相似文献   
110.
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