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91.
Ultrasensitive magnetic biosensor for homogeneous immunoassay   总被引:3,自引:0,他引:3       下载免费PDF全文
A technique is described for specific, sensitive, quantitative, and rapid detection of biological targets by using superparamagnetic nanoparticles and a "microscope" based on a high-transition temperature dc superconducting quantum interference device (SQUID). In this technique, a mylar film to which the targets have been bound is placed on the microscope. The film, at room temperature and atmospheric pressure, is typically 40 micrometer from the SQUID, which is at 77 K in a vacuum. A suspension of magnetic nanoparticles carrying antibodies directed against the target is added to the mixture in the well, and 1-s pulses of magnetic field are applied parallel to the SQUID. In the presence of this aligning field the nanoparticles develop a net magnetization, which relaxes when the field is turned off. Unbound nanoparticles relax rapidly by Brownian rotation and contribute no measurable signal. Nanoparticles that are bound to the target on the film are immobilized and undergo Néel relaxation, producing a slowly decaying magnetic flux, which is detected by the SQUID. The ability to distinguish between bound and unbound labels allows one to run homogeneous assays, which do not require separation and removal of unbound magnetic particles. The technique has been demonstrated with a model system of liposomes carrying the FLAG epitope. The SQUID microscope requires no more than (5 +/- 2) x 10(4) magnetic nanoparticles to register a reproducible signal.  相似文献   
92.
We report here the case of a woman with joint pains found to have antinuclear antibodies and undetectable serum haemolytic complement. Investigation of her and her family members showed an inherited deficiency of C6.  相似文献   
93.
94.
Of 26 Ashkenazi Jewish patients with pemphigus vulgaris, 24 (92.3%) carried the major histocompatibility complex (MHC) class II alleles HLA-DR4, DQw3, of which all were of the subtype DR4, DQw8. From studies of the patients and their families, haplotypes were defined. It was found that, of the patients who carried HLA-DR4, DQw8, 75% carried one or the other (and in one case, both) of two haplotypes [HLA-B38, SC21, DR4] or HLA-B35, SC31, DR4. The former is a known extended haplotype among normal Jews, with a frequency of 0.102, and the latter may also be an extended haplotype in this ethnic group, with a frequency of 0.017 among normal haplotypes from Jews. Of the remaining DR4-positive patients, all but one had a presumed D-region segment (defined as SC21, DR4, DQw8 or SC31, DR4, DQw8 with variable HLA-B) of these haplotypes. Only one patient had DR4, DQw8 without any other markers of the extended haplotypes. The number of homozygotes and heterozygotes for DR4, DQw8 was consistent with dominant but not recessive (P less than 0.01) inheritance of a class II or a class II-linked susceptibility gene for the disease. Since the disease is entirely attributable to the presence of an antibody to an intraepidermal intercellular cement substance, it is likely that the class II susceptibility gene (on [HLA-B38, SC21, DR4, DQw8], HLA-B35, SC31, DR4, DQw8, or their segments, in Jewish patients) controls the production of the antibody as a dominantly expressed immune response gene.  相似文献   
95.
The purpose of this study was to compare the effects of aerobic training with a muscle-strengthening program in patients with fibromyalgia. Thirty women with fibromyalgia were randomized to either an aerobic exercise (AE) program or a strengthening exercise (SE) program for 8 weeks. Outcome measures included the intensity of fibromyalgia-related symptoms, tender point count, fitness (6-min walk distance), hospital anxiety and depression (HAD) scale, and short-form health survey (SF-36). There were significant improvements in both groups regarding pain, sleep, fatigue, tender point count, and fitness after treatment. HAD-depression scores improved significantly in both groups while no significant change occurred in HAD-anxiety scores. Bodily pain subscale of SF-36 and physical component summary improved significantly in the AE group, whereas seven subscales of SF-36, physical component summary, and mental component summary improved significantly in the SE group. When the groups were compared after treatment, there were no significant differences in pain, sleep, fatigue, tender point count, fitness, HAD scores, and SF-36 scores. AE and SE are similarly effective at improving symptoms, tender point count, fitness, depression, and quality of life in fibromyalgia.  相似文献   
96.
Anomalous right coronary artery is a rare entity with an incidence of 0.26%. The anomalous origin usually arises from the left sinus valsalva. An anomalous right coronary artery arising from the left anterior descending artery is rare. It is usually known as a benign entity but may have clinical importance due to its course between the aorta and pulmonary artery which may cause myocardial ischemia or sudden cardiac death. Here we present an anomalous coronary artery arising from the left anterior descending artery detected by coronary artery angiogram and confirmed by multislice computed tomography thereafter. 40% retrospective electrocardiographic gating is performed and volume-rendered 3 D and axial MIP (maximum intensity projection) images were reconstructed on a Vitrea post- processing Workstation. The images demonstrated the anomalous origin of the right coronary artery arising from the proximal portion of left anterior descending artery after the first septal perforator and coursing.  相似文献   
97.
According to World Health Organization, the life expectancy at birth is increasing. An increase in life expectancy might result in increased morbidity and mortality in elderly. The increase in the elderly population also leads to an increase in medico-legal problems, as well. Autopsy is of high importance for determination of cause of death in clinical and forensic cases. The purpose of this study was to find out general characteristics elderly deaths by examining forensic autopsy records.  相似文献   
98.
Red cell distribution width (RDW) and neutrophil/lymphocyte ratio (NLR) have been found to be associated with cardiovascular diseases. Only a few trials have investigated the correlation of these parameters with postoperative atrial fibrillation (AF). However, the correlation of these parameters in non-valvular AF is still unclear. We retrospectively analyzed consecutive AF patients from medical records and included 117 non-valvular AF patients (103 paroxysmal and 14 chronic AF). All subjects underwent physical examination and echocardiographic imaging. Complete blood counts (CBCs) were analyzed for hemoglobin, RDW, neutrophil and lymphocyte counts as well as mean corpuscular volume. Results of CBC tests within the previous year were also included and the averages were used. The demographic and echocardiographic properties of non-valvular AF group were comparable to the control group except for left atrial volumes which were increased in AF (median 33.1, IQR 26.3–41.1 cm3 vs. median 26.4, IQR 24.2–28.9 cm3; p = 0.01). RDW levels were significantly higher in the AF group (median 13.4 %, IQR 12.9–14.1 %) compared to the control (median 12.6 %, IQR 12.0–13.1 %; p = 0.01). NLR was not statistically different in the AF group and the controls (2.04 ± 0.94 vs. 1.93 ± 0.64, respectively; p = 0.32). Hs-CRP levels were higher in the AF group compared to the controls (median 0.84, IQR 0.30–1.43 mg/L vs. median 0.29, IQR 0.18–0.50 mg/L, respectively; p = 0.01). Multivariate logistic regression analysis revealed RDW (OR 4.18, 95 % CI 2.15–8.15; p = 0.01), hs-CRP (OR 3.76, 95 % CI 1.43–9.89; p = 0.01) and left atrial volume (OR 1.31, 95 % CI 1.06–1.21; p = 0.01) as the independent markers of non-valvular AF. Multivariate linear regression analysis revealed that hemoglobin levels (standardized β coefficient = ?0.252; p = 0.01) and the presence of AF (standardized β coefficient = 0.336; p = 0.01) were the independent correlates of RDW levels. Elevated RDW levels, not NLR, may be an independent risk marker for non-valvular AF.  相似文献   
99.
100.
Aim: We aimed to investigate the prophylactic effects of trimetazidine (TMZ) against contrast-induced nephropathy (CIN) in rat kidneys. Methods and results: 28 Wistar rats were divided into 4 groups of 7 rats each (control (C), contrast media (CM) TMZ, trimetazidin?+?contrast media groups (TMZ?+?CM). The administration of TMZ solution was done on d2, d3 and d4. Fifth day, contrast media was administered at a single dose. On d6 scarification was performed. The oxidant/antioxidant parameters were measured and histopathological scores were performed in kidney tissues. Most of the histopathological scores were significantly higher in the CM group as compared to other groups. Moreover, the scores of the TMZ?+?CM and C groups were not statistically different. CM group, had significantly higher levels of MDA compared to the C and CM?+?TMZ groups (562.82?±?38.15 vs. 419.15?±?49.01 and 507.34?±?14.16 01?nmol/mg protein respectively) (p?0.001). CM group had significantly lower levels of SOD as compared to C, CM?+?TMZ and TMZ groups (p?0.05). Conclusion: To the best of our knowledge, this study for the first time, histopathologically demonstrated the effectiveness of TMZ for the prevention of CIN.  相似文献   
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