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91.
Migraine-associated vertigo   总被引:2,自引:0,他引:2  
A retrospective analysis was performed on consecutive series of 363 patients presenting with vertigo; 32% had migraine. Of the 224 patients with no pathology other than migraine or vestibular dysfunction, migraineurs had a significantly higher prevalence of normal, central, and combined central and peripheral vestibular dysfunction compared to non-migraineurs. The combination of central and peripheral vestibular signs was a feature of migraine with aura. The results support the hypothesis that migraine-associated vertigo is a diagnostic entity.  相似文献   
92.
BACKGROUND: Chagas' disease is transmitted to man either by the bite of insects harboring Trypanosoma cruzi or by the transfusion of blood from infected donors. The conventional serologic testing as presently used in blood banks in South America is unsatisfactory, because of a high number of inconclusive and false-positive results. Other methods such as polymerase chain reaction and enzyme-linked immunosorbent assay (ELISA) with recombinant antigens have been proposed, but inherent difficulties have so far precluded their adoption in the large-scale screening required by blood banks. STUDY DESIGN AND METHODS: A highly sensitive and specific chemiluminescent ELISA using a purified trypomastigote glycoconjugate antigen and a complex epimastigote antigen was devised for the diagnosis of active T. cruzi infection. RESULTS: Chemiluminescent ELISA was 100-percent sensitive in the diagnosis of 100 cases of confirmed Chagas' disease. Inconclusive results and false-positive reactions were eliminated in a panel of 115 sera.The specificity of the chemiluminescent ELISA was 100 percent with a purified trypomastigote glycoconjugate antigen and 99.7 percent with a complex epimastigote antigen when applied to 1000 normal human sera and 288 heterologous sera from patients with other infections, including leishmaniasis, and vaccinated individuals. CONCLUSION: The chemiluminescent ELISAs provide a test that is highly sensitive (purified trypomastigote glycoconjugate and complex epimastigote antigens) and specific (purified trypomastigote glycoconjugate antigen) for Chagas' disease diagnosis. It can be used in blood bank screening and to monitor the treatment of patients undergoing chemotherapy.  相似文献   
93.
Immunoadsorption for coagulation factor inhibitors   总被引:1,自引:0,他引:1  
Inhibitors to coagulation factors are among the most difficult problems in the management of coagulation disorders. Most presently available therapy does not assure hemostasis. An extracorporeal immunoadsorption system, which selectively binds IgG, was used to lower inhibitor levels in eight patients on 10 occasions. In this system, separated plasma is delivered to two staphylococcal protein A-Sepharose columns, which are coupled to an elution monitor. Columns are eluted sequentially and regenerated to maximize IgG removal. Successful removal of the inhibitor was accomplished in all six hemophiliacs on seven occasions, as well as in a patient with acquired von Willebrand disease. All patients whose inhibitors were lowered to less than 10 Bethesda units achieved measurable factor levels when factor concentrate replacement was given. Immunoadsorption facilitates efficient removal of inhibitors, which allows factor replacement therapy.  相似文献   
94.
Cell surface proteins major histocompatibility complex (MHC) class I-related chain A (MICA) and UL16-binding proteins (ULBP) 1, 2, and 3 are up-regulated upon infection or tumor transformation and can activate human natural killer (NK) cells. Patches of cross-linked raft resident ganglioside GM1 colocalized with ULBP1, 2, 3, or MICA, but not CD45. Thus, ULBPs and MICA are expressed in lipid rafts at the cell surface. Western blotting revealed that glycosylphosphatidylinositol (GPI)-anchored ULBP3 but not transmembrane MICA, MHC class I protein, or transferrin receptor, accumulated in detergent-resistant membranes containing GM1. Thus, MICA may have a weaker association with lipid rafts than ULBP3, yet both proteins accumulate at an activating human NK cell immune synapse. Target cell lipid rafts marked by green fluorescent protein-tagged GPI also accumulate with ULBP3 at some synapses. Electron microscopy reveals constitutive clusters of ULBP at the cell surface. Regarding a specific molecular basis for the organization of these proteins, ULBP1, 2, and 3 and MICA are lipid modified. ULBP1, 2, and 3 are GPI anchored, and we demonstrate here that MICA is S-acylated. Finally, expression of a truncated form of MICA that lacks the putative site for S-acylation and the cytoplasmic tail can be expressed at the cell surface, but is unable to activate NK cells.  相似文献   
95.
目的:探讨多孔髓芯减压联合自体骨髓干细胞移植治疗股骨头坏死的疗效及临床分析。方法:选择2003-02/2006-12在南京医科大学附属南京第一医院骨关节中心采用多孔髓芯减压联合干细胞移植治疗的股骨头坏死患者22例,共28髋,年龄17~48岁,根据世界骨循环研究学会(ARCO)的国际骨坏死分期标准:Ⅰ期13髋,Ⅱ期11髋,Ⅲ期4髋。长期使用激素史9例,长期酗酒史6例,外伤史5例,原因不明者2例。纳入标准:有髋关节疼痛,功能受限;经髋关节X射线片及MRI检查确诊;ARCO分期Ⅰ~Ⅲ期;患者知情同意并签署知情同意书。排除标准:其他髋关节疾病。自患者髂前上棘处行骨髓穿刺分离与培养骨髓间充质干细胞。取患肢大粗隆下大腿外侧纵向直切口约3.0cm,钝性分离至股骨,在C形臂机引导下自股骨头中心钻入3枚直径4.0mm斯氏针,选位置较好的斯氏针,将直径约8.0mm特制套管在斯氏针的引导下钻至股骨头关节软骨面下1.0~2.0mm,不穿破关节面。将一长注射器针头置入股骨头坏死中心,立即行X射线正侧位摄片,确保针头位于股骨头内,从针头向股骨头内加压注入自体骨髓间充质干细胞悬液1.5~2.0mL。术后12个月随访,每3个月1次,随访时门诊复查,拍正、侧位和蛙式位X射线片,行MRI检查,观察病情变化。使用髋关节Harris评分进行疗效评价,>90分为优,75~90分为良,60~74分为可,<60分评定为差。若Harris评分提高,X射线骨形态变化改善及MRI股骨头坏死区体积变小可认为联合治疗有效。结果:①22例患者均完成随访,进入结果分析。②随访3个月时X射线及MRI检查:2例(2髋)激素引起的Ⅲ期患者股骨头发生进一步变形及塌陷,其余患者在随访期间未出现严重并发症,不良反应及病情恶化。股骨头坏死体积由术前31.07%减小到17.46%。激素组治疗前后股骨头坏死体积差值小于外伤、酗酒组,就本随访资料而言激素组疗效不如外伤及酗酒组。③随访12个月Harris评分:由术前54.3上升到84.6,有较明显提高,其中优7髋(25.0%),良15髋(53.6%),可4髋(14.3%),差2髋(0.07%)。结论:多孔髓芯减压联合干细胞移植是治疗股骨头坏死的一种新手段,尤其适合于年青、ARCO-Ⅰ或Ⅱ期、非激素导致的股骨头坏死治疗。  相似文献   
96.
BACKGROUND: The Roche CARDIAC proBNP point-of-care (POC) test is the first test intended for the quantitative determination of N-terminal pro-brain natriuretic peptide (NT-proBNP) in whole blood as an aid in the diagnosis of suspected congestive heart failure, in the monitoring of patients with compensated left-ventricular dysfunction and in the risk stratification of patients with acute coronary syndromes. METHODS: A multicentre evaluation was carried out to assess the analytical performance of the POC NT-proBNP test at seven different sites. RESULTS: The majority of all coefficients of variation (CVs) obtained for within-series imprecision using native blood samples was below 10% for both 52 samples measured ten times and for 674 samples measured in duplicate. Using quality control material, the majority of CV values for day-to-day imprecision were below 14% for the low control level and below 13% for the high control level. In method comparisons for four lots of the POC NT-proBNP test with the laboratory reference method (Elecsys proBNP), the slope ranged from 0.93 to 1.10 and the intercept ranged from 1.8 to 6.9. The bias found between venous and arterial blood with the POC NT-proBNP method was < or =5%. All four lots of the POC NT-proBNP test investigated showed excellent agreement, with mean differences of between -5% and +4%. No significant interference was observed with lipaemic blood (triglyceride concentrations up to 6.3 mmol/L), icteric blood (bilirubin concentrations up to 582 micromol/L), haemolytic blood (haemoglobin concentrations up to 62 mg/L), biotin (up to 10 mg/L), rheumatoid factor (up to 42 IU/mL), or with 50 out of 52 standard or cardiological drugs in therapeutic concentrations. With bisoprolol and BNP, somewhat higher bias in the low NT-proBNP concentration range (<175 ng/L) was found. Haematocrit values between 28% and 58% had no influence on the test result. Interference may be caused by human anti-mouse antibodies (HAMA) types 1 and 2. No significant influence on the results with POC NT-proBNP was found using volumes of 140-165 muL. High NT-proBNP concentrations above the measuring range of the POC NT-proBNP test did not lead to false low results due to a potential high-dose hook effect. CONCLUSIONS: The POC NT-proBNP test showed good analytical performance and excellent agreement with the laboratory method. The POC NT-proBNP assay is therefore suitable in the POC setting.  相似文献   
97.
Background: The diagnostic and prognostic use of cardiac troponin T (cTnT) in patients with renal failure has been questioned. Raised serum concentrations of cTnT, with no apparent signs of cardiac damage using conventional methods of detection, have been reported. We aimed to relate circulating concentrations of cTnT to improved renal function following renal transplantation over a one-year period. Method: Plasma cTnT was analysed from patients with end stage renal disease before and after transplantation and subsequently at 1, 3, 6 and 12 months. Eight patients had diabetes, 14 had hyperlipidaemia, 8 were smokers and 4 were ex-smokers; all were hypersensitive. Results: At the time of transplantation, 3 of the 32 patients (9.4%) had plasma cTnT concentrations above 0.1 μg/l. In addition to these three patients, five others showed raised cTnT over the one-year period. Conclusions: The overall trend in circulating cTnT concentrations did not seem to be affected by improved renal function. However, all of the patients that had raised cTnT concentrations at any stage of the one-year period had explainable pathologies or were exposed to multiple cardiac risk factors.  相似文献   
98.
BACKGROUND: Hospitals and blood centers throughout the United States use a variety of reagents and methods to perform pretransfusion testing. A survey was developed to determine the reagents and methods in use and their relative prevalence in different work settings. STUDY DESIGN AND METHODS: A national survey on pretransfusion testing was conducted. Surveys were distributed to state and regional blood bank associations, which then distributed them to hospitals and blood centers within their region. In most instances, the blood centers distributed the survey to the local hospitals. Completed surveys were returned to the authors for review, and all information was entered into a database for analysis. RESULTS: Analysis of the data shows that the majority of blood banks use monoclonal reagents for ABO testing and monoclonal-polyclonal blended reagents for Rh testing. The data show that anti-IgG and polyclonal antihuman globulin reagents are used almost equally for antibody screening (detection) tests and that most blood banks use a three-cell antibody-screening test. Slightly more than 50 percent of hospitals use an immediate-spin crossmatch in the absence of unexpected antibodies. CONCLUSION: A number of approved reagents and methods are used by blood bank laboratories for pretransfusion testing. Facility size (number of beds) and type tend to influence the choice of methods and reagents employed. This survey provides an opportunity for blood bank laboratories to compare their current practices with those of their peers.  相似文献   
99.
A double-blind provocative study chocolate as a trigger of headache   总被引:1,自引:0,他引:1  
A provocative double blind study of headache was performed using chocolate as the active agent and carob as the placebo. The chocolate and carob samples were formulated to duplicate products used in an earlier study (1) in which strong differential effects between the ability of chocolate and carob to trigger headache in migraine were shown. Sixty-three women with chronic headache (50% migraine, 37.5% tension-type, 12.5% combined migraine and tension-type) participated in the study. After 2 weeks of following a diet that restricted vasoactive amine-rich foods, each subject underwent double-blinded provocative trials with two samples of chocolate and two of carob presented in random order. Diaries were maintained by the subjects throughout the study, monitoring diet and headache. The results demonstrated that chocolate was not more likely to provoke headache than was carol in any of the headache diagnostic groups (2(2) 0.36, p =0.83). Interestingly, these results were independent of subjects' beliefs regarding the role of chocolate in the instigation of headache (2(1)=0.73, p =0.39). Headache diagnosis and the concomitant use of additional vasoactive amine-containing foods were also not associated with chocolate acting as a headache trigger. Thus, contrary to the commonly held belief of patients and physicians, chocolate does not appear to play a significant role in triggering headaches in typical migraine, tension-type, or combined headache sufferers.  相似文献   
100.
目的:观察胶体磷酸铬32P关节腔内注射治疗大鼠佐剂型关节炎的效果。方法:实验于2006-07/09在南京市第一医院动物实验室完成。选择6~8周龄清洁级SD雌性大鼠30只,按随机数字表法分为3组,正常对照组、模型组、胶体磷酸铬32P治疗组,每组10只。大鼠左足跖皮内注射完全弗氏佐剂0.1mL免疫法制备佐剂型关节炎模型。胶体磷酸铬32P治疗组于造模后10d左踝关节腔内注射37GBq/L胶体磷酸铬32P0.02mL,即0.74MBq,正常对照组和模型组分别给予等量生理盐水左踝关节腔内注射。①每2周观察1次大鼠左踝关节左右径宽度。②关节炎指数评定采用关节炎评分法(0~4分),分数越高,症状越重。③于用药后2,4,6周采用99Tcm-MDP显像感兴趣区分析法计算大鼠左踝关节区和右胫腓骨的放射性计数比。④于用药后4,6周测定血清肿瘤坏死因子和白细胞介素1β水平。⑤于用药后4,6周观察大鼠滑膜组织和软骨组织病理学改变。结果:纳入大鼠30只,均进入结果分析。①用药后2周模型组大鼠左踝关节左右径宽度大于正常对照组[分别为(7.82±0.36),(5.89±0.35)mm],差异有显著性意义(t=12.16,P<0.001),胶体磷酸铬32P治疗组大鼠左踝关节左右径宽度大于模型组,差异无显著性意义(P>0.05)。用药后6周胶体磷酸铬32P治疗组大鼠左踝关节左右径宽度小于模型组[分别为(6.87±0.27),(7.25±0.26)mm],差异有显著性意义(t=2.87,P<0.05)。②用药后2周和4周胶体磷酸铬32P治疗组大鼠关节炎指数高于模型组,用药后6周胶体磷酸铬32P治疗组大鼠关节炎指数低于模型组,两组间差异均无显著性意义(P>0.05)。③用药后2周模型组大鼠感兴趣区放射性计数比高于正常对照组(分别为2.05±0.20,1.46±0.15),差异有显著性意义(t=7.46,P<0.001)。用药后6周胶体磷酸铬32P治疗组大鼠感兴趣区放射性计数比低于模型组(分别为1.52±0.18,1.78±0.24),差异有显著性意义(t=2.45,P<0.05)。④用药后4,6周模型组大鼠血清肿瘤坏死因子和白细胞介素1β水平高于正常对照组,差异有显著性意义[用药后4周分别为(2.039±0.344),(1.115±0.192)μg/L;(0.305±0.034),(0.192±0.041)μg/L,t=7.42,6.71,P<0.001。用药后6周分别为(1.694±0.305),(1.126±0.256)μg/L;(0.259±0.027),(0.191±0.019)μg/L,t=4.03,5.83,P<0.01,0.001]。用药后4,6周胶体磷酸铬32P治疗组在血清肿瘤坏死因子和白细胞介素1β水平与模型组比较,差异无显著性意义(P>0.05)。⑤用药后4周胶体磷酸铬32P治疗组和模型组滑膜组织增生和炎症细胞浸润均较明显;用药后6周胶体磷酸铬32P治疗组与正常对照组比较仍有滑膜组织增生和炎症细胞浸润,与模型组比较滑膜组织增生程度明显减轻,而炎症细胞浸润程度稍轻。用药后6周胶体磷酸铬32P治疗组大鼠左踝关节的软骨组织未见有异常改变。结论:胶体磷酸铬32P关节腔注射可减轻完全弗氏佐剂免疫大鼠受注射关节的滑膜增生程度,改善关节肿胀症状,疗效肯定。  相似文献   
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