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1.
A case of recurrent medullary thyroid cancer (MTC) was evaluated with123I-MIBG,99mTc(V)-dimercaptosuccinic acid (DMSA), and201Tl scintigraphy. This patient had been operated on for MTC in the right thyroid. Recently a left neck mass was noticed, and was suspected of being a. recurrence of MTC based on increased plasma calcitonin (CT) and carcinoembryonic antigen (CEA). He was operated on for the neck mass which revealed MTC, and papillary thyroid cancer was incidentally found in the left thyroid, but the CT and CEA levels remained high, and remaining MTC tumor was suspected. But the location of the tumor was unknown. Although99mTc(V)-DMSA scintigraphy is generally believed to be superior in sensitivity to123I-MIBG scintigraphy, it did not demonstrate the tumor site but201Tl and123I-MIBG did. Furthermore,123I-MEBG scintigraphy has greater specificity for tumors which arise in the neural crest. Judging from the results of this case and cases reported in the literatures, both123I-MIBG and99mTc(V)-DMSA should be performed in the detection of recurrent MTC.  相似文献   
2.
Differentiation of impaired gait seen in idiopathic normal pressure hydrocephalus (iNPH) from parkinsonian gait is sometimes a great challenge and important for future medication in the clinical setting. To investigate dopaminergic contribution to its pathophysiology, two aspects of the trans-synaptic dopamine functions in the striatal region in eight iNPH patients na?ve to dopaminergic drugs were examined using positron emission tomography with a presynaptic marker [11C]CFT ([11C]2-beta-carbomethoxy-3beta-(4-fluorophenyl) tropane) that binds to dopamine transporter and a postsynaptic marker [11C]raclopride that binds to D2 receptor. Quantitative values of binding potentials (BPs) for [11C]CFT and [11C]raclopride were compared between patients and eight age-matched healthy subjects. The BPs and magnetic resonance imaging-based morphometric measures in iNPH were used for correlation analyses between the magnitude of binding of these in vivo markers and clinical severity of the patients. Analysis of variance showed significant reduction in [11C]raclopride binding in the putamen and nucleus accumbens (P<0.05, corrected for multiple comparison) and unchanged striatal [11C]CFT binding in iNPH. The dorsal putamen [11C]raclopride binding correlated negatively with gait severity (r=0.720, P<0.05), and the nucleus accumbens [11C]raclopride binding correlated positively with emotional recognition score (r=0.727, P<0.05) in the disease group. No significant relationship was observed between BPs and morphometric measures. The current result of the postsynaptic D2 receptor reduction along with preserved presynaptic activity in the nigrostriatal dopaminergic system reflects a pathophysiology of iNPH. Postsynaptic D2 receptor hypoactivity in the dorsal putamen may predict the severity of gait impairment in iNPH.  相似文献   
3.
We measured platelet counts in 95 patients with hematological disorders accompanied by thrombocytopenia (platelet counts < 5.0 x 10(4)/microliter) including 35 patients with severe thrombocytopenia(platelet counts < 2.0 x 10(4)/microliter). We used four methods based on different principles and compared the results, i.e., the flow cytometric method (BEADS method) utilizing platelet-specific monoclonal antibody (SZ2, antiGPIb) in conjunction with fluorescent reference beads (Flow-Count Fluorospheres), manual hemocytometry, and two automated blood cell counters, the NE-8000 (impedance method) and the Technicon H-2 (optical method). The BEADS method was superior to the other methods in linearity of serial dilutions, and the coefficient variations of the BEADS method(2.5-5.2%) were superior to the other methods. The platelet counts measured by the automated blood cell counters were higher(0.6-0.9 x 10(4)/microliter) than those by the BEADS method and manual hemocytometry. Furthermore, the BEADS method was able to measure accurate platelet counts in samples containing red blood cell fragments. The BEADS method may be an accurate and useful method for measuring samples with severe thrombocytopenia, and, especially, samples containing red blood cell fragments.  相似文献   
4.
Platelet counts measured by automated blood cell counter often show spuriously high values when measuring samples contain particles of equal size to platelets. The major cause of spuriously high platelet counts in samples with fragmented red cells (FRC) is thought to be the FRC themselves. We studied the correlation between FRC and spuriously high platelet counts in 40 patients demonstrating FRC on blood smears. FRC were measured by manual hemocytometry and by flow cytometry using a monoclonal antibody against glycophorin A (GPA method). There was a significant correlation between spuriously high platelet counts and FRC by manual hemocytometry (r=0.60, p<0.001) or FRC by the GPA method (r=0.45, p<0.005). These data suggest that FRC are the major cause of spuriously high platelet counts in samples with FRC.  相似文献   
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6.
Anti-prothrombin antibodies (anti-prothrombin) and anti-beta2-glycoprotein I antibodies (anti-beta2-GP I) are the most common and characterized anti-phospholipid antibodies (aPL) detected using specific enzyme-linked immunosorbent assay (ELISA) systems. Recently, lupus anti-coagulant (LA) activity detected by a phospholipid-dependent coagulation assay was reported to be associated with anti-prothrombin and/or anti-beta2-GP I. Here we show that the co-existence of IgG anti-prothrombin and LA activity might be an essential risk factor for venous thromboembolism (VTE) in patients with systemic lupus erythematosus (SLE). We examined not only the levels of antibodies to prothrombin and anti-beta2-GP I (both IgG and IgM isotypes) using an ELISA system, but also LA activity detected using both diluted Russell's viper venom time (dRVVT) and STACLOT LA test in 124 patients with SLE. The SLE patients were divided into four groups according to the results of ELISA and LA assay results for each aPL: group A, ELISA+ and LA+ group B, ELISA+ and LA-; group C, ELISA- and LA+ group D, ELISA- and LA-. Regarding IgG anti-prothrombin, the prevalence of VTE was significantly higher in group A (16/35 cases, 45.7%, P < 0.001, Fisher's exact probability test) than in the other groups (B, 2/30, 6.7%; C, 1/22, 4.5%; D, 1/37, 2.7%). With respect to IgM anti-prothrombin and IgG or IgM anti-beta2-GP I, the prevalence of VTE was higher in both groups A and C than in group D, but no statistical difference in prevalence was found between groups A and C. Multivariate logistic regression analysis of risk factors for VTE confirmed that the co-existence of IgG anti-prothrombin and LA activity was the only significant risk factor for VTE (odds ratio, 19.13; 95% confidence intervals, 4.74-77.18).  相似文献   
7.
Cultured rat hepatocytes were used to study the effects of hormones on the production of apo A-I. In addition, we compared these effects with the production of albumin. Hepatocytes were isolated from normal adult rat livers and cultured in MEM, as nearly confluent monolayers. In the absence of hormones, apo A-I and albumin accumulated in the culture medium almost linearly for periods up to 24 h. The rates of accumulation of apo A-1 and albumin in the medium were 22 ng/mg cell protein per h and 1.2 μg/mg cell protein per h, respectively. During the incubations the cellular contents of apo A-1 remained constant.

Insulin stimulated the production of albumin at concentrations over 10−10 M, but inhibited the production of apo A-I at concentrations over 10−8 M. Dexamethasone showed no significant effects on albumin production but stimulated apo A-1 production at concentrations over 10−6 M. Glucagon inhibited the production of albumin and apo A-I dose-dependently at concentrations over 10−10 M. Thus, the production of albumin and apo A-1 are presumably controlled by different regulatory mechanisms.  相似文献   

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9.
Serum levels of interleukin-1 (IL-1β), interleukin-6 (IL-6), interleukin-8 (IL-8), tumor necrosis factor (TNF-α), and granulocyte-macrophage colony-stimulating factor (GM-CSF) were measured preoperatively in 24 patients with colorectal cancer. IL-1β was not elevated, IL-6 and IL-8 were markedly elevated, and GM-CSF was slightly elevated. TNF-α was not detected in most patients. Serum IL-6 levels correlated closely with serum IL-8 levels and with serum carbohydrate antigen (CA) 19-9 levels. Serum IL-6 levels were significantly higher in patients whose tumors exceeding 5.0 cm in diameter or spreading circumferentially. Serum IL-8 levels showed significant differences according to histological type, being lower in well differentiated adenocarcinoma compared to other types. Serum levels of IL-6 and IL-8 were significantly higher in patients with liver metastasis than in those without liver metastasis and serum levels of both these cytokines were also significantly higher in patients with lung metastasis than in those without lung metastasis. These results suggest that IL-6 and IL-8 may play an important role in the hematogenous metastasis of colorectal cancer.  相似文献   
10.
Objective. The main objective of this study was to clarify therole of aPLs in the pathogenesis of arteriosclerosis obliterans(ASO), ischaemic heart disease (IHD) and cerebral vascular disorder(CVD) in patients with SLE. Methods. We evaluated 155 patients with SLE by using objectivetests for diagnosing ASO, IHD and CVD and laboratory tests includingELISA for aCL/β2-glycoprotein I antibodies (aCL/β2-GPI)and anti-phosphatidylserine/prothrombin antibodies (anti-PS/PT). Results. Twenty-five (16.1%) of the 155 SLE patients were diagnosedwith ASO. Both aCL/β2-GPI and anti-PS/PT levels were significantlyhigher in SLE patients with ASO (mean ± S.E., 104.3 ±38.8 U/ml for aCL/β2-GPI, P < 0.01; 72.6 ± 48.9U/ml for anti-PS/PT, P < 0.05) than in SLE patients withoutASO (22.8 ± 9.9 U/ml for aCL/β2-GPI; 18.3 ±4.4 U/ml for anti-PS/PT). Multivariate logistic analysis includingaCL/β2-GPI, anti-PS/PT and traditional risk factors (hypercholesterolaemia,hypertension and diabetes mellitus) confirmed that the presenceof aCL/β2-GPI was the most significant risk factor forASO in SLE patients [odds ratio (OR) 3.45; 95% CI 1.40, 8.56;P < 0.01]. Furthermore, the prevalence of ASO was associatedstrongly with IHD (OR 11.8; 95% CI 3.45, 40.1; P < 0.0001)but not CVD (OR 1.84; 95% CI 0.65, 5.21; P = 0.25). Conclusions. The presence of aCL/β2-GPI contributes tothe risk of development of ASO, which may represent an importantmechanism for the pathogenesis of IHD in patients with SLE. KEY WORDS: Systemic lupus erythematosus, Anti-phospholipid antibodies, Arteriosclerosis obliterans, Ischaemic heart disease, Cerebral vascular disorder Submitted 12 December 2007; revised version accepted 22 February 2008.  相似文献   
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