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101.
102.
Abstract

Design of an MR-compatible and computer-controlled odour stimuli system is essential in the studies of human olfactory function. Olfactometers are used to deliver odours to the subjects in an objective manner. We present a portable, computer-controlled eight channels olfactometer able to stimulate olfaction by employing liquid odorant stimuli. We used a high-pressure pump to generate medical grade airflow. After passing through solenoid valve-controlled odour reservoirs, odorant stimulus is conveyed to the nasal mask. The odour delivery delay of the device was measured using photo-ionisation detectors. To assess the application of the designed olfactometer, an fMRI experiment was done with 9 healthy subjects. Two odour stimuli (Vanillin and Rose) were presented to each subject in an alternating block design task of odour and non-odour conditions. The response time of each subject was gathered using the response box. Group analysis revealed a significant BOLD signal change in some regions of olfactory and trigeminal networks including the orbitofrontal cortex, insula, inferior frontal gyrus, hippocampus, cingulate gyrus and piriform cortex. The odour delivery delay measured by photo-ionisation detector was 190?ms, and the subjects’ response showed 205?ms for the Vanillin and 243?ms for the Rose odour stimuli. Our portable MR-compatible olfactometer as a stimulation device is capable of creating adequate stimulation suitable for olfactory fMRI experiments.  相似文献   
103.
Background and ObjectiveChronic inflammation is the typical sign of gastritis that may shift into gastric cancer. IL-17A and IL-17F as a novel inflammatory cytokines subset of CD4+Th play the main role in inflammation. A key cytokine receptor in the inflammatory IL-17/IL-23 axis, the interleukin 23 receptor (IL23R), may be related to gastritis. We evaluated the correspondence between IL-17A G197A, IL-17F A7488G and IL23R+2199 A/C polymorphisms with TGF-β1, IL-6, IL-17, IL-21 and IL-23 mucosal mRNAs expression in uninfected H. Pylori (HP) chronic gastritis patients.Materials and MethodsTotal RNA and genomic DNA were separated from gastric biopsies of 44 patients with gastritis. Subsequently, mucosal mRNAs expression of TGF-β1, IL-6, IL-17, IL-21 and IL-23 were assessed by real-time PCR. To polymorphisms determination of IL-17A G197A, IL-17F A7488G and IL-23R +2199A/C the PCR-RFLP was used in gastric biopsies.ResultsResults point that IL-17A G197A, IL-17F A7488G and IL23R +2199A/C polymorphisms did not influence the mucosal expression of TGF-β1, IL-6, IL-17 and IL-21 (p> 0.05). In an opposite result, we don''t find a correspondence between IL-17A G197A, IL-17F A7488G polymorphisms and mucosal expression of IL-23 (p> 0.05). In a contrary, we found a correlation between IL23R +2199A/C polymorphism and mucosal expression of IL-23 in patients with chronic gastritis (p< 0.05).ConclusionThese findings propose that IL23R +2199A/C polymorphism may change the mucosal expression of IL-23 pattern in patients with gastritis disease in the absence of HP, but to support the conclusion, more research may be required.  相似文献   
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105.
Rapid and effective diagnosis of brucellosis is a challenge for clinicians. Even when diagnosis is on time and therapy is initiated, meticulous follow-up appointments are crucial for ensuring the efficacy of the treatment. Due to shortcomings of serological methods, molecular diagnosis, especially real-time PCR, is becoming a main approach in laboratory diagnostics. Thus, the development of efficient procedures and standardization of the PCR tests will have a great impact on the precise detection and quantification of bacterial DNA loads, which is valuable for the medical management of brucellosis patients. We developed a new TaqMan real-time PCR directed to bcsp31, a shared gene of the brucellae. The bcsp31 gene fragment was cloned into pJET1.2. Recombinant pJET1.2-bcsp31 was linearized by HindIII digestion, and the product was used for the preparation of a standard curve. A panel of Brucella spp. and non-Brucella pathogens was tested. No bacterial genomes other than those of the brucellae were detected. According to the results, specificity of the method was 100%. In a clinical assessment, the positive-control group comprised 37 patients with microbiologically confirmed brucellosis, and 25 healthy individuals served as the negative-control group. By the end of the treatment period, there was a significant decrease in the DNA load of the 37 brucellosis patients, which persisted for the 4 weeks of monitoring after treatment, suggesting that our proposed method is an efficient monitoring tool. Serum samples prior to any treatment were collected from the 25 serologically suspicious patients and assessed by our method; 72% of these patients tested positive for brucellosis.  相似文献   
106.
107.
4,4′-(1,4-phenylene)bis(2-(alkylamino)-3-nitro-4H-benzo[g]chromene-5,10-dione) and 4,4′-(1,4-phenylene)bis(2-(alkylamino)-3-nitropyrano[3,2-c]chromen-5(4H)-one) derivatives are synthesized by a one-pot, multi-component reaction of N-alkyl-1-(methylthio)-2-nitroethenamine (derived from the reaction of various amines and 1,1-bis(methylthio)-2-nitroethene) with terephthalaldehyde or isophthalaldehyde, and 2-hydroxy-1,4-naphthoquinone or 4-hydroxycoumarin in EtOH/H2O (85 : 15) as the solvent at 89 °C. Response surface methodology (RSM) is used to investigate the effect of reaction temperature and water content of aqueous ethanol on the product yields and reaction time. The notable features of this work are the optimization of reaction conditions with minimal experiments, absence of catalyst, good yields, simple work-up and the non-chromatographic purification of products.

One-pot synthesis of C2-symmetric chromene derivatives, which serve as building blocks to prepare liquid crystals with potential electrical or optical properties.  相似文献   
108.
In this study, the histamine concentration in the muscle tissue of whole rainbow trout (Oncorhynchus mykiss) was monitored during ice storage for a period of 18 days (0, 3, 6, 9, 12, 15 and 18th day). Results showed that the concentration of histamine increased linearly (P?<?0.05) during ice storage (except the 18th day). Histamine was not detected at the first and third day of storage. The first detection of histamine was in the sixth storage day. Initial concentration of histamine was 1.09 μg/g and finally reached to 4.30 μg/g. The maximum histamine levels was reported to be below the Australian Food Standards Code (2001) safe level (200 mg/kg), and histamine levels were low even after 18 days of storage and remained below the Food and Drug Administration (2001) tolerance level during ice storage. It seems that the levels of histamine could be a suitable freshness indicator of rainbow trout during ice storage.  相似文献   
109.
MIBG is an effective component in treatment of neuroblastoma. Furthermore, MIBG scintigraphy is an imaging modality in primary assessments. None of the previous studies have evaluated the role of pretransplant MIBG scintigraphy in decision making for neuroblastoma treatment. We selected therapeutic regimen based on pretransplant 131I‐MIBG scintigraphy. Twenty high‐risk patients were enrolled. On day ?30, patients underwent diagnostic MIBG scintigraphy. Patients were then subdivided into two groups (10 cases in each arm). MIBG‐avid subgroup received MIBG (12 mCi/kg), etoposide (1200 mg/m2), carboplatin (1500 mg/m2), and melphalan (210 mg/m2). Non‐MIBG‐avid subgroup received etoposide (600 mg/m2), carboplatin (1200 mg/m2), and melphalan (150 mg/m2). Patients received CRA after ASCT. Mean age at diagnosis was 42.5 months (range, 17–65) in MIBG‐avid and 38.9 months (range, 18–65) in non‐MIBG‐avid patients. Mean age at diagnosis and transplantation did not reveal significant difference between two subgroups. In MIBG‐avid patients, the three‐yr OS was 66 ± 21%. In MIBG‐non‐avid subgroup, the three‐yr OS was 53 ± 20%. In MIBG‐avid and non‐MIBG‐avid subgroups, the three‐yr EFS were 66 ± 21% and 47 ± 19%, respectively. These findings may suggest an effective role in selecting the therapeutic strategy for pre‐ASCT MIBG scintigraphy in high‐risk neuroblastoma. MIBG‐avid subset may benefit from the combination of therapeutic MIBG and high dose of chemotherapy.  相似文献   
110.
Restenosis remains the major limitation of coronary stent implantation, especially in diffuse forms of in-stent restenosis. In this study, rotablation (RA) with adjunct angioplasty of in-stent restenosis was performed in 84 patients. Clinical follow-up and control angiography were obtained 6-month postprocedure. The rate of recurrent restenosis after rotablation for in-stent restenosis at 6-month angiographic follow-up was 45%, resulting in a rate of major adverse cardiac events of 35%. At 3-year follow-up, the cumulative event-free survival rate was 57% for the entire population. The only predictor of MACE at 3-year clinical follow-up by multivariate logistic regression analysis was in-stent lesion length. RA for the treatment of diffuse in-stent restenosis is thereby characterized by high procedural success rates and recurrent angiographic restenosis in 45% of patients with diffuse lesions. Major adverse cardiac events occur most likely within the first 6 months postprocedure. Three years after rotablation of in-stent restenosis, 43% of patients had experienced at least one major adverse cardiac event. Cathet Cardiovasc Intervent 2001;53:334-340.  相似文献   
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