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排序方式: 共有925条查询结果,搜索用时 15 毫秒
71.
目的建立室内质控参考品以鉴别诊断试剂的质量和控制操作误差,提高乙型肝炎病毒表面抗原的检测准确度。方法以国家标准品为标准制备灵敏度系列参考品、特异性参考品及精密性参考品。检测其稳定性,并进行同厂家、不同批号试剂的比较及不同厂家、三批试剂的比较。结果制备的室内质控参考品在-20℃与4℃保存3~4周检测结果无统计学差异。采用同一厂家、不同批号的HBsAg诊断试剂检测室内质控参考品,结果无统计学差异。采用不同厂家、同一批号的HBsAg诊断试剂检测结果有统计学差异。结论我们建立的室内质控参考品适宜作HBsAg室内质控,提醒我们在更换试剂厂家时应特别注意室内质控参考品的变化。 相似文献
72.
目的 探讨应用非每日千伏级锥形束CT(KVCBCT)校位能否改善摆位误差对鼻咽癌调强放疗(IMRT)剂量分布影响。方法 对14例行根治性IMRT的鼻咽癌患者治疗开始后连续5次用KVCBCT检测摆位误差,并将其均值作为系统误差预测值,若其>1.5 mm则在第6次离线校位。假设通过移床能完全校正系统误差,那么从第6次起实际各方向摆位误差值加上离线校位值可得到未行校位时的摆位误差值,在治疗计划系统中通过等中心移位重新计算剂量来模拟应用非每日校位策略前后摆位误差所致的剂量变化。结果 对10例系统误差预测值>1.5 mm者摆位误差明显降低了靶区剂量:98%大体肿瘤体积(GTV)所接受剂量(GTV-D98)平均减少3.8Gy(Z=-2.81,P=0.005),原发灶临床靶体积(CTVns) D95( CTVns-D95)平均减少4.8Gy(Z=-1.96,P=0.050),高危CTV1 -D95平均减少1.0Gy(Z=-2.82,P=0.005),低危CTV2-D95减少不明显(Z=-0.13,P=0.900)。应用非每日校位后明显减少了摆位误差的三维方向位移总量,均值从3.6 mm减少为2.6mm(t=2.00,P=0.000),GTV-D98平均增加3.8 Gy(Z=-2.70,P=0.007),CTVns-D95平均增加5.0Gy(Z=-2.15,P=0.030),CTV1 -D95平均增加0.9Gy(Z=-2.80,P=0.005),减少了危及器官剂量增加>3%、5%患者比例。结论 应用非每日KVCBCT校位能有效减少摆位误差对鼻咽癌IMRT剂量分布的不利影响。 相似文献
73.
目的:观察复方土牛膝糖浆剂在体外和动物模型上的抗病毒作用。方法:用细胞培养法,通过观察细胞病变评价复方土牛膝糖浆剂对常见的致上呼吸道感染的柯萨奇B族病毒4型(CoxB4)、副流感病毒(HVJ)、呼吸道合胞病毒(RSV)、单纯疱疹病毒(HSV-Ⅰ)所致的细胞病变(CPE)的抑制作用;通过用流感病毒滴鼻感染小鼠来研究复方土牛膝糖浆剂对病毒感染小鼠所引起的死亡保护作用。结果:复方土牛膝糖浆在体外对CoxB4、RSV病毒的致细胞病变作用有明显抑制作用,其IC50分别为2.0、2.8μL糖浆/mL,TI分别为5.6和4,对HSV-1、副流感-1型病毒的致细胞病变有一定的抑制作用。其IC50分别为4.0、5.0μL糖浆/mL,TI分别为2.8和2.24。在小鼠感染病毒15天内,复方土牛膝糖浆5mL/(kg.d)剂量组动物的死亡率为55%;死亡保护率分别为38.39%,与感染对照组相比有显著差异(P<0.05),复方土牛膝糖浆10mL/(kg.d)、5mL/(kg.d)两个剂量组小鼠的存活天数较感染组明显延长,与对照组比较有显著性差异。生命延长率分别为17.67%和22.22%。结论:复方土牛膝糖浆剂无论在体内或是体外均有较明显的抗病毒作用。 相似文献
74.
息风化痰通腑汤合醒脑静注射液治疗急性脑出血疗效观察 总被引:1,自引:0,他引:1
目的观察息风化痰通腑汤合醒脑静治疗急性脑出血的临床疗效。方法将53例中小量脑出血(≤30 ml)患者随机分成2组。治疗组29例在常规西医综合治疗基础上,加用息风化痰通腑汤合醒脑静注射液治疗;对照组24例仅采用常规西医综合治疗。2组均14日为1个疗程,判定疗效。结果:治疗组有效率93.1%,对照组83.3%,2组比较有显著性差异(P<0.05),治疗组疗效显著优于对照组。2组治疗前后昏迷情况比较、血肿吸收情况及神经功能缺损积分对比,均有显著性差异(P<0.01),且治疗组疗效明显优于对照组(P<0.01)。结论息风化痰通腑汤合醒脑静注射液治疗中小量急性脑出血,能提高治愈率,降低病死率,缩短治疗时间,提高生存质量,无明显毒副作用。 相似文献
75.
Daniels DL; Czervionke LF; Millen SJ; Haberkamp TJ; Meyer GA; Hendrix LE; Mark LP; Williams AL; Haughton VM 《Radiology》1989,171(3):807-809
The authors evaluated magnetic resonance (MR) images obtained with intravenously administered gadolinium in ten patients who had facial paralysis and no facial nerve tumor. In patients with either Bell palsy (four patients) or facial paralysis after temporal bone surgery (six patients), intratemporal facial nerve enhancement was seen. Facial nerve enhancement on MR images proved to be a nonspecific finding. 相似文献
76.
77.
Intracranial abnormalities in infants treated with extracorporeal membrane oxygenation: imaging with US and CT 总被引:1,自引:0,他引:1
Findings at neuroimaging in 100 consecutive infants treated with extracorporeal membrane oxygenation (ECMO) are presented. Imaging in these infants consisted of pretreatment cranial ultrasonography (US), daily US studies while on ECMO, and follow-up cranial computed tomography (CT) after treatment. There were findings of abnormalities in 43 patients. Thirty had intracranial bleeding, often of unusual extent and distribution. Thirteen additional infants had nonhemorrhagic abnormalities alone. Bleeding considered to be major was seen in 12% of infants. Large parenchymal hemorrhages and infarcts, cerebellar hemorrhages, and diffuse edema were the most significant abnormalities, with a 50% mortality (eight of 16 patients). No lateralization was noted with respect to distribution of bleeding sites or areas of nonhemorrhagic abnormalities. US was a sensitive but imperfect screening tool for intracranial abnormalities. Abnormalities missed with US included peripheral and small parenchymal lesions, subarachnoid hemorrhage, cerebral atrophy, and sagittal sinus thrombosis. 相似文献
78.
79.
Peptic ulcer and gastric carcinoma: diagnosis with biphasic radiography compared with fiberoptic endoscopy 总被引:1,自引:0,他引:1
Shaw PC; van Romunde LK; Griffioen G; Janssens AR; Kreuning J; Eilers GA 《Radiology》1987,163(1):39-42
The diagnostic value of biphasic radiographic examination of the stomach and duodenum was compared with that of fiberoptic endoscopy in a prospective, blinded study of 385 patients with dyspepsia. This investigation was directed at gastric malignancies and peptic ulcers. Methodologically there is no absolute standard for a study of this kind because histologic examination is useful for detection of cancer but inadequate for ulcers. As an alternative, kappa indexes and the sensitivity and specificity, as derived by Hui and Walter, were calculated and compared. For the detection of gastric carcinoma, radiographic and endoscopic findings had almost perfect agreement beyond chance. For gastric ulcers, radiography and endoscopy had substantial agreement, which became perfect if small ulcers (less than 5 mm) were excluded. For duodenal ulcers, radiography had a lower sensitivity than endoscopy; this disagreement disappeared if small ulcers were excluded. Both methods have equal merit; choice of the initial diagnostic procedure will therefore depend on cost, discomfort to the patient, and risk of complications. 相似文献
80.
Parathyroid scintigraphy using a double-tracer (T1-201, Tc-99m) subtraction technique depicted 17 of 23 (74%) parathyroid adenomas in patients with and without previous neck operations. High-resolution (10-MHz) ultrasound (US) depicted 18 (78%) of these adenomas. Average tumor size depicted by US was 17 X 10 X 8 mm (excluding a giant adenoma) and 19 X 10 X 9 mm by scintigraphy. Alone, neither modality was particularly sensitive in the depiction of primary hyperplasia of the parathyroid glands, but combined techniques were more effective than the use of a single modality. With both US and T1-201 scintigraphy, only two of 23 cases of parathyroid adenoma in the neck were missed, and none of the eight cases of secondary hyperplasia were missed. In 11 patients who had previously undergone neck surgery, parathyroid tumors were identified in eight by either US or double-tracer scintigraphy. Preoperative parathyroid imaging with double-tracer scintigraphy and high-resolution US is suggested for patients with hyperparathyroidism, particularly in those patients who have had previous parathyroid surgery. 相似文献