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The subthalamic nucleus (STN) is a major target for treatment of advanced Parkinson's disease patients undergoing deep brain stimulation surgery. Microelectrode recording (MER) is used in many cases to identify the target nucleus. A real-time procedure for identifying the entry and exit points of the STN would improve the outcome of this targeting procedure. We used the normalized root mean square (NRMS) of a short (5 seconds) MER sampled signal and the estimated anatomical distance to target (EDT) as the basis for this procedure. Electrode tip location was defined intraoperatively by an expert neurophysiologist to be before, within, or after the STN. Data from 46 trajectories of 27 patients were used to calculate the Bayesian posterior probability of being in each of these locations, given RMS-EDT pair values. We tested our predictions on each trajectory using a bootstrapping technique, with the rest of the trajectories serving as a training set and found the error in predicting the STN entry to be (mean +/- SD) 0.18 +/- 0.84, and 0.50 +/- 0.59 mm for STN exit point, which yields a 0.30 +/- 0.28 mm deviation from the expert's target center. The simplicity and computational ease of RMS calculation, its spike sorting-independent nature and tolerance to electrode parameters of this Bayesian predictor, can lead directly to the development of a fully automated intraoperative physiological procedure for the refinement of imaging estimates of STN borders.  相似文献   
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30余种氨基酸、40余种非挥发性有机酸和20余种碱基核苷类化合物在一块薄层板上完成多相同步色谱分析;用紫外灯-吖啶试剂-镉茚三酮试剂实行组合显色定位分析。改善了尿液中非挥发性有机酸的溶剂萃取法,尿中三类化合物提取物的同步多相色谱分离效果良好。  相似文献   
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Genetic polymorphism in the ABO blood group gene of Han, Kazak and Uygur populations inhabiting the most northwestern part of China was investigated using polymerase chain reaction-based techniques. The present study enrolled 43 healthy unrelated Han, 37 Kazak and 59 Uygur volunteers. The allele in A1 blood group is distinguished A0101 and A0102 in difference of nucleotide position 467. The A0101 allele is more frequent in Caucasian and the A0102 allele is characteristic in Mongoloid. It must be notable that A0201 in the A2 group (with a single base deletion at nucleotides 1059 to 1061) which was characteristic of Caucasian was observed in Kazak and Uygur populations but not in Han. Further, 00201 (with no nucleotide deletion at 261 and three nucleotide differences), which is frequent in different races including Caucasian except for Mongoloid, was detected also in Kazak and Uygur populations. The frequencies of B0101 in Kazak, Uygur and Han were comparable to those of other Asian populations but higher than those of Caucasian populations. Collectively, these results reveal that the allele frequencies of Kazak and Uygur at the ABO blood group locus are an intermediate between those of Mongoloid and Caucasian, suggesting the admixed feature of Kazak and Uygur with Mongoloid and Caucasian.  相似文献   
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Interferon regulatory factor-1 (IRF-1) is pivotal in the regulation of interferon (IFN)-mediated immune reactions, and studies suggest that IRF-1 is involved in the development of autoimmune diseases. IRF-1+/+, +/-, and -/- nonobese diabetic (NOD) mice were immunized with mouse thyroglobulin (mTg) to determine whether IRF-1 is required in experimental autoimmune thyroiditis (EAT), a murine model for Hashimoto's thyroiditis (HT). IRF-1-deficient mice developed EAT and anti-mTg antibodies comparable to IRF-1+/+ and +/- mice. Whereas both CD4+ and CD8+ T cells were found in thyroids of IRF-1+/+ mice, the latter was not in IRF-1-/- mice. Major histocompatibility complex class II antigen was comparably expressed in thyroids of IRF-1+/+ and -/- mice. Lack of IRF-1 resulted in decreased CD8+ T cell number in the spleen and reduced IFNgamma production by splenocytes. Our results suggest that IRF-1 is not pivotal in EAT in NOD mice.  相似文献   
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BackgroundHolmium laser enucleation of the prostate (HoLEP) has been a widely utilized minimally invasive surgical procedure for benign prostate hyperplasia. The current study aimed to compare surgical outcomes and King’s Health Questionnaire (KHQ) assessment scores following HoLEP between younger men and those aged ≥75 years.MethodsThis prospective single-center study compared perioperative complications, postoperative urinary conditions, and KHQ scores (nine categories) between men aged ≥75 years (group A) and men aged <75 years (group B) before and 1, 3, and 6 months after surgery.ResultsA total of 100 patients were included for analysis (group A, n=38 and group B, n=62). No differences in patient backgrounds, perioperative complications, such as perioperative decrease in hemoglobin, postoperative fever, postoperative indwelling catheterization duration, or postoperative hospitalization duration, and KHQ were observed between both groups. Both groups showed significantly better International Prostate Symptom Scores, quality of life, maximum urinary flow rate, and postvoid residual volume 1, 3, and 6 months after HoLEP compared to their respective preoperative levels (P<0.01). Regarding KHQ categories, both groups showed significantly better general health perceptions, impact on life, emotions, and sleep/energy 1 month after HoLEP; role limitations, physical limitations, and social limitations 3 months after HoLEP; and personal relationships and incontinence severity measures 6 months after HoLEP compared to their respective preoperative levels (P<0.05).ConclusionsHoLEP could be safe and effective even for men aged ≥75 years, comparing complications, urinary condition, and KHQ scores.  相似文献   
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Most national lymphoma registers rely on broad classifications which include Hodgkin and non-Hodgkin lymphomas (NHL), multiple myeloma and leukaemia. In Poland the National Histopathological Lymphoma Register project (NHLR) was implemented by hematopathologists in accordance with the 2008 WHO classification into haematopoietic and lymphoid tissues. We present the NHLR data and compare lymphoma distribution in Poland, Europe, as well as in North Central and South America. Records of 11718 patients diagnosed in 24 pathology departments from all over the country were retrieved and reclassified into indolent and aggressive lymphomas according to the 2008 revised WHO classification system. DLBCL (32.9%; 2587), CLL/SLL (31.84%; 2504) and MCL (9.04%; 711) were the three most frequent NHL. The ratio of indolent to aggressive NHL was 1.72; 63.25% (4809) to 36.25% (2794) of cases respectively. Multiple myeloma was less frequent as compared to the data from population-based national cancer register (13.32% vs. 28.94%). Major differences between NHLR and European and American data on NHL subtypes concered: higher incidence of aggressive B-cell lymphomas including DLBCL, lower FL and MALT incidence rate. The percentage of unclassified lymphomas in the study was minimal due to participation of hematopathologists.  相似文献   
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