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71.
本文将聚乙二醇(PEG)比浊法和固相酶联免疫法(ELISA)结合,建立了—较灵敏的免疫复合物(IC)直接固相吸附抗原特异性检测法。利用牛清蛋白(BSA)为已知抗原组份的IC模型,分别对IC直接固相吸附的条件和影响因素、方法的灵敏度、重复性等进行了研究。结果发现IC在解离状态下直接固相吸附后的抗原特异性检测灵敏度明显高于未解离者。该法具有简单易行,灵敏度较高、适于临床测定大量血清样品等优点。 相似文献
72.
73.
Abstract: Spontaneous intracranial hypotension (SIH) is a postural headache syndrome unrelated to dural puncture. Because of the increasing failure of epidural blood patch (EBP) to relieve headache in SIH, we retrospectively investigated the epidemiological features and treatment outcomes in 55 cases of SIH. The study population was stratified by age and sex; continuous variables were compared for differences by t -tests; categorical variables were compared by Chi-squared analysis or Fisher exact tests. Significant differences were identified by P values of 0.05 or less. The mean age of the study population was 44 ± 12 years with a female to male ratio of 1.3:1.0. Men presented with subdural hematomas ( P = 0.001) more often than women. Meningeal enhancement on contrast magnetic resonance imaging (MRI) was the most consistent radiographic finding. Radionuclide cisternography (RC) demonstrated thoracolumbar dural leaks in 16 of 22 patients. EBP failures were more common in patients aged 40 and younger than in older patients ( P = 0.003). Postural headache from SIH was not uniformly responsive to EBP, and had significant comorbidities, especially in men. The management of postural headache in SIH by other techniques to restore brain position and cerebrospinal fluid dynamics should be investigated. 相似文献
74.
75.
去除白细胞输血的临床意义 总被引:1,自引:0,他引:1
目的:评估去除白细胞输血的临床应用价值。方法:251例患者接受了去除白细胞红细胞悬液761U,(每人1 ̄8U不等),对其中200U红细胞悬液滤除白细胞前、后分别进行白细胞计数和血红蛋白测定,并对其输血反应进行了观察。结果:发现应用白细胞滤器后,其白细胞数比过滤前显著减低,过滤前、后白细胞数分别为(6.16±1.44)×109/L与(0.12±0.10)×109/L(P<0.01),血红蛋白过滤前、后无显著性差异,分别为:(161.58±23.31)g/L与(157.84±22.35)g/L,P>0.05。251例接受去白细胞受血者均未出现输血反应。结论:白细胞滤器能有效去除白细胞,去除白细胞能减少非溶血性输血反应。 相似文献
76.
岛状皮瓣静脉淤血再通后对大鼠全身情况的影响 总被引:4,自引:0,他引:4
目的:探讨岛状皮瓣静脉淤血再通后对全身多脏器的影响。方法:按静脉淤血时间的不同将大鼠分为4组。观察耳部微循环的改变,测量术后肿瘤坏死因子α(TNFα),白细胞介素10(IL-10)的动态变化,观察心,肺,肝,肾,小肠及耳部血管等组织结构及中性粒细胞浸润数目。结果:皮瓣原位缝合组及静脉淤血2h组,耳部微循环、TNFα、IL-10浓度基本保持不变,各脏器结构改变较轻,中性粒细胞浸润数目少。静脉淤血6、10h组,微循环,肺,小肠,血管则有明显组织学改变,大量中性粒细胞浸润其中,但心,肝,肾组织学改变较轻。TNFα浓度再灌注1h达到高峰,其后逐渐下降,IL-10浓度3h达到最低,然后逐渐上升。结论:皮瓣静脉淤血再通后可造成肺、小肠及血管器官损伤,静脉淤血时间越长,再通后则损伤程度越重。全身微循环的改变,中性粒细胞在肺、小肠中的浸润,与血管内皮细胞的粘附及细胞因子TNFα与IL-10的浓度失衡是重要的操作原因。 相似文献
77.
Hiroomi Murayama Masanobu Meda Ken Miyahara Yoshimasa Sakai Hajime Sakurai Hiroki Hasegawa Akemi Kawamura 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2003,51(3):91-97
Objective: We assessed the current role of preoperative and intraoperative autologous blood donation in pediatric open-heart surgery.
Methods: Group 1 consisted of 51 patients between 5 and 10 years old who underwent preoperative autologous blood donation. Group
2 consisted of 50 age-matched patients without preoperative donation as controls. Intraoperative donation was conducted in
both groups prior to cardiopulmonary bypass. We evaluated perioperative blood cell count, blood loss, and the need for homologous
blood products. Results: No serious complications occurred in preoperative or intraoperative donation. Total preoperative donation storage was 17.5±3.4
mL/kg. Intraoperative donation was 21.7 ±6.1 mL/kg in Group 1 and 12.8±4.0 mL/kg in Group 2 (p<0.001). On admission, serum
hemoglobin was lower in Group 1 (12.2±1.0 g/dL versus 13.6±1.6 g/dL, p<0.001) but returned postoperatively to the preoperative
value. It hovered at a depressed level in Group 2 (12.2±1.4 versus 10.2±1.1 g/dL, p<0.001). The homologous blood requirement
was significantly less in Group 1 than in Group 2 (0% versus 10%, p<0.05). Postoperative platelet counts showed similar curves,
and blood loss was not statistically significantly different between groups. Conclusion: Preoperative and intraoperative donations are safe and continue to contribute uniquely to blood conservation, providing
important options in comprehensive blood conservation programs in current pediatric open-heart surgery. 相似文献
78.
刘尊年 《菏泽医学专科学校学报》2002,14(4):84-85
目的 探讨血细胞自动计数的方法。方法 采用微机彩色图像处理技术对血液细胞图像进行图像分割和细胞计数。结果 与人工计数相平行 ,相关系数r =0 .96 1~ 0 .997,P >0 .0 5。结论 该方法可行且计数相对精确、迅速、客观 相似文献
79.
计算法测定肾小球滤过率的临床应用价值 总被引:7,自引:2,他引:5
目的 :探讨采用 WCP公式计算方法测定肾小球滤过率 (GFR)的临床应用价值。方法 :采用 99m Tc DTPA清除率测定 6 6例不同疾病住院患者 GFR(Tc GFR) ,并测血清肌酐 (SCr)及尿素氮 (BU N) ,同时以 WCP公式、Robert公式计算 GFR(WCP GFR,Robert GFR) ,以 Cockcroft/ Gault公式计算内生肌酐清除率 (CG CCr) ,所得数据进行对比研究及相关性分析。结果 :除肾功能正常者 CG CCr与 BU N无显著相关外 ,肾功能不全及肾功能正常者的 WCP GFR、Robert GFR、CG CCr均分别与 Tc GFR呈显著正相关(P均 <0 .0 1) ,与 BU N、SCr呈显著负相关 (P<0 .0 1或 P<0 .0 5 ) ;与 Robert GFR、CG CCr比较 ,WCPGFR始终与 Tc GFR最接近 (P均 >0 .0 5 ) ;WCP GFR、Robert GFR、CG CCr与 Tc GFR的平均差绝对值逐渐增大 ,三者间差异显著 (P均 <0 .0 5 )。结论 :WCP GFR、Robert GFR、CG CCr均能在一定程度上准确反映 GFR,而以 WCP GFR更准确 ,且简便、快速、安全而廉价 ,可代替 Tc GFR应用于临床 相似文献
80.
Theoretical and simulation evidence is presented in support of the idea that the optimal manner of determining blood flow from MR perfusion studies is not necessarily obtained by setting experimental conditions to maximize either the arterial input or the measured tissue concentration level for a particular echo time (TE). The noise power in the contrast concentration curve is associated with its peak because of the nonlinear relationship between the contrast concentration and MR signal intensity curves. The optimum signal-to-noise ratio (SNR), SNR(C), for a particular contrast concentration curve can be obtained when the experimental concentration level and TE are adjusted to produce an MR intensity curve whose signal loss is 63% of the precontrast MR signal intensity. It is demonstrated that the stability of the singular valued decomposition (SVD) deconvolution approach to determine blood flow parameters is increased when the tissue curve maximum signal loss is in the range of 40-80%. The accuracy and stability of the SVD-determined blood flow parameters are affected by deviations from these optimum conditions in a manner that depends on the mean transit time (MTT) associated with the residue function. It is recommended that the experimental TE value be set so that neither the tissue nor the arterial curves are placed a region of rapidly deteriorating SNR(C). 相似文献