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McGowan  EB; Detwiler  TC 《Blood》1985,65(4):1033-1035
The effect of a zinc metalloprotease from Serratia marcescens on platelet surface glycoproteins (GP) Ib and V was analyzed. Increasing protease treatments caused progressive loss of GP Ib with appearance of the major fragment, glycocalicin, in the supernatant solution. No GP V was detected in the supernatant solution, and protease-pretreated platelets had the same capacity as control platelets to release fragment 1 of GP V in response to thrombin. The Serratia protease- pretreated platelets did show the lag before thrombin-induced dense granule secretion, characteristic of platelets modified by pretreatment with other nonstimulating proteases. Treatment with Serratia protease gives the only demonstrated selective loss of GP Ib without apparent effect on GP V. It suggests that GP V (1) does not depend on GP Ib for its association with platelets and (2) is not the substrate for protease modification of platelet function.  相似文献   
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To assess the dosimetric effect of using interpolated contours in planning intensity‐modulated radiation therapy (IMRT) for advanced T‐stage nasopharyngeal carcinoma. The present study focused on T3–T4 tumours where the proximity of targets to neurological organs poses a stringent test on the feasibility of such an approach. Contours of targets and organs were delineated on CT images of 2.5‐mm interval and a reference IMRT plan was generated. An investigative (INV) IMRT plan was then generated with the same planning protocol, but based on interpolated contours that replaced deleted contours on alternate slices. The reference and INV plans were compared. Regarding target coverage, all targets in the INV plans met the acceptance criteria except for the PTV in one case. Regarding organs, the mean dose to 1% volume of the brainstem and spinal cord in the INV plans were kept below their dose limits. No significant differences in the mean doses to others organs were found. Satisfactory target coverage and protection of critical organs to a degree similar to full‐scale contouring could be achieved with use of interpolated contours. The saving in manpower time for contouring is expected to significantly improve the throughput of the IMRT planning process.  相似文献   
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Ectopic thyroid   总被引:3,自引:0,他引:3  
Primary mediastinal ectopic goiters are very rare. We report a case in which an ectopic goiter with blood supply from the thoracic vessels necessitated a transternal approach for removal, resulting in a favorable outcome.  相似文献   
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Differences in morphology between "benign" and "malignant" breast calcifications were observed in a pilot study utilizing scanning electron microscopy and x-ray analysis. Preliminary data suggest that there may also be chemical differences between calcifications and in the surrounding tissue.  相似文献   
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目的探讨缺血性中风证侯分类的客观量度。方法本研究对118例缺血性中风患者按中医证类进行分组,观察各证类组病例的血脂、血压及血液流变学改变。结果研究表明,风痰阻络证、痰热腑实证及气虚血瘀证组脂质变化较正常组明显升高(P<0.05~0.01),其中风痰阻络证、痰热腑实证与气虚血瘀证组存在显著差异(P<0.05);气虚血瘀证、风痰阻络证及痰热腑实证组血液流变学指标较正常组有显著差异(P<0.05~0.01);肝阳暴亢证、痰热腑实证组血压明显高于气虚血瘀证、风痰阻络证及阴虚风动证组(P<0.05~0.01)。结论血脂、血压及血液流变学指标可为缺血性中风证候分类提供客观量度。  相似文献   
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The femur length/abdominal circumference ratio, expressed as FL/AC X 100, was determined in 156 fetuses and evaluated as a predictor of fetal macrosomia within one week prior to delivery. The normal range (mean +/- 2 SD) in the 105 normal-weight fetuses was 22.0 +/- 2, while the normal range in the 51 macrosomic fetuses was 20.5 +/- 2; these differences were highly significant (P = less than .0001). The predictive power of a positive ratio was 68%, with a sensitivity of 63%. This ratio was particularly useful in the subset (n = 9) of macrosomic fetuses whose mothers were diabetic, correctly identifying 89% of this group. Because it is age independent, this ratio should prove most helpful in identifying fetuses at risk for macrosomia in patients whose dates are not known, since it may become abnormal before the fetal weight falls above the 90th percentile at term (3,900 g). In patients whose dates are known, early fetal macrosomia is best predicted by evaluating the abdominal circumference against normal standards for age.  相似文献   
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