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81.
The chaotic neural network constructed with chaotic neurons exhibits rich dynamic behaviour with a nonperiodic associative memory. In the chaotic neural network, however, it is difficult to distinguish the stored patterns in the output patterns because of the chaotic state of the network. In order to apply the nonperiodic associative memory into information search, pattern recognition etc. it is necessary to control chaos in the chaotic neural network. We have studied the chaotic neural network with threshold activated coupling, which provides a controlled network with associative memory dynamics. The network converges to one of its stored patterns or/and reverse patterns which has the smallest Hamming distance from the initial state of the network. The range of the threshold applied to control the neurons in the network depends on the noise level in the initial pattern and decreases with the increase of noise. The chaos control in the chaotic neural network by threshold activated coupling at varying time interval provides controlled output patterns with different temporal periods which depend upon the control parameters. 相似文献
82.
R.R. Razonable J.S. Pulido P.J. Deziel S. Dev D.R. Salomão R.C. Walker 《Transplant infectious disease》2008,10(6):413-418
Abstract: Whipple's disease is a very rare chronic multisystemic bacterial disease characterized by diarrhea, malabsorption, fever, and polyarthritis. Ocular manifestations occur very rarely. Previous reports have suggested that the use of immunosuppressive drugs appears to accelerate or exacerbate the clinical course of Whipple's disease; however, the illness has yet to be reported in the setting of transplantation. Herein, we describe what we believe is the first reported case of Whipple's disease after transplantation. The patient is a 51‐year‐old woman who developed progressive visual floaters and blurring of vision 30 years after living‐related kidney transplantation for an autosomal‐dominant polycystic kidney disease. Her allograft was functioning well on maintenance immunosuppressive therapy with azathioprine and prednisone when she developed visual abnormalities. Transient weight loss, gastrointestinal symptoms, and migratory polyarthralgia predated the onset of ocular disease by several years. The diagnosis of Whipple's bilateral vitreitis and chorioretinitis was confirmed by polymerase chain reaction analysis demonstrating Tropheryma whipplei nucleic acid in vitreous fluid and peripheral blood sample as well as by demonstration of the bacilli by cytopathology. Intraocular vancomycin, intravenous ceftriaxone, and prolonged course of oral trimethoprim‐sulfamethoxazole therapy led to clinical improvement and recovery of visual acuity. 相似文献
83.
A rare case of primary tuberculosis of bilateral submandibular salivary glands is presented with review of relevant literature.
The patient was managed on conservative therapy. 相似文献
84.
85.
D Pate D Resnick M Andre D J Sartoris S Kursunoglu D Bielecki P Dev A Vassiliadis 《AJR. American journal of roentgenology》1986,147(3):545-551
An evaluation of musculoskeletal disorders in 202 patients using three-dimensional CT displays has revealed the usefulness of the technique, especially in patients with fractures of skeletal areas with complex anatomy, articular disorders of the hip, and spinal stenosis. In some cases, plastic models of diseased areas have been created from the CT data and are reasonably accurate, providing a graphic representation of the disease and the ability to perform rehearsal surgery. A preliminary investigation of three-dimensional displays of MR images indicates that the technique is feasible, although its clinical practicality requires further analysis. 相似文献
86.
Jyotsna Bhatt Archana Mukherjee Aruna Korde Mukesh Kumar Haladhar Dev Sarma Ashutosh Dash 《Molecular imaging and biology》2017,19(1):59-67
Purpose
The present work was aimed at the development of prospective positron emission tomography (PET) agents for infection imaging. Towards this aim, ubiquicidin (UBI) fragments conjugated with the macrocyclic NODAGA chelator were radiolabeled with Ga-68 and evaluated.Procedures
Conformations of custom synthesized NODAGA-UBI (29–41) and NODAGA-UBI (31–38) conjugates were compared with UBI (29–41) by circular dichroism (CD) spectroscopy. Optimization of labeling of NODAGA conjugates of UBI peptides with Ga-68 was performed and quality control analysis was carried out by chromatography techniques. In vitro uptake of [68Ga] NODAGA-UBI (29–41) and [68Ga]NODAGA-UBI (31–38) was studied in Staphylococcus aureus cells. In vivo distribution of [68Ga]GaCl3 and [68Ga]NODAGA-UBI complexes was performed in normal Swiss mice.Results
Conformations of NODAGA-UBI (29–41) and NODAGA-UBI (31–38) conjugates were found to be similar to UBI (29–41). NODAGA-UBI conjugates could be consistently labeled with Ga-68 in high radiochemical yields (>95 %) with high radiochemical purity (>95 %). [68Ga]NODAGA-UBI (29–41) and [68Ga]NODAGA-UBI (31–38) complexes showed retention time of 14 and 14.5 min, respectively, by HPLC radiochromatogram. Specific uptake of [68Ga]NODAGA-UBI fragments was observed in S.aureus cells. Greater than 64 % of the injected dose was cleared via the renal route at 1 h post injection, and no significant uptake in vital organs of mice was observed with both the agents.Conclusion
This is the first report on Ga-68 labeled NODAGA-UBI fragments for infection imaging and the agents hold tremendous prospect in PET imaging.87.
Boccon-Gibod L Bertaccini A Bono AV Dev Sarmah B Höltl W Mottet N Tunn U Zamboglou N 《International journal of clinical practice》2003,57(3):187-194
This report summarises the findings of a European Consensus Group review of current standards of care in locally advanced prostate cancer defined as (a) untreated cancer extending clinically beyond the prostatic capsule in patients with no evidence of lymph node invasion or distant metastases, and (b) residual disease remaining after local treatment with positive surgical margins, seminal vesicle invasion, persistent prostate-specific antigen (PSA) and/or secondary PSA relapse. There was no overall consensus as to the standard of care in clinically apparent locally advanced prostate cancer. It was agreed, however, that hormonal therapy (e.g. with a gonadotrophin releasing hormone analogue [GnRHa]) represents a valid treatment in these patients. Treatment practices and regimens vary considerably between European countries, but GnRHa is widely used, either alone or in combination with antiandrogens. Hormonal therapy alone is a valid option, though the optimal modality, timing and duration of treatment remain to be defined. Adjuvant therapy with a GnRHa has been shown to improve survival in patients undergoing external beam radiotherapy. It is a viable option after prostatectomy in patients with persistent or secondary relapsing PSA. It was determined that optimal treatment will be different according to PSA, clinical staging and Gleason score, and the treatment of locally advanced disease should be individually tailored after discussion between physician and patient. In many instances, patients prefer and expect some form of treatment in preference to watchful waiting. Treatment nomograms such as the Kattan nomograms provide precise, comprehensive and invaluable tools for everyday use and may be used to predict outcomes and guide treatment decisions. 相似文献
88.
The natriuretic peptides and their role in disorders of right heart dysfunction and pulmonary hypertension 总被引:11,自引:0,他引:11
Atrial natriuretic peptide (ANP) and B-type natriuretic peptide (BNP) are increased in conditions with cardiac ventricular volume and pressure overload. The general physiological and potential therapeutic roles of natriuretic peptides in respiratory disease, right ventricular (RV) dysfunction, and pulmonary arterial hypertension (PAH) are reviewed. BNP levels can be used to differentiate between dyspneic patients with a pure respiratory defect and those with RV dysfunction. BNP levels also correlate with mean pulmonary arterial pressure (mPAP) and pulmonary vascular resistance (PVR) in patients with PAH (atrial septal defect, chronic thromboembolic disease, and scleroderma). BNP is a predictor of mortality in patients with primary pulmonary hypertension (PPH). These are important clinical implications in that a noninvasive blood test may be used to identify high-risk patients for more invasive procedures such as cardiac catheterization. BNP or NT-proBNP measurements may also be used to guide therapy (e.g., pulmonary vasorelaxants) in PAH since upregulation of the natriuretic peptide pathway has been shown to reduce cardiac hypertrophy and PAH. Additionally, there may be therapeutic potential via recombinant BNP or neutral endopeptidase inhibitors in RV dysfunction and PAH. 相似文献
89.
Lalit Aggarwal Shubham Jain Rahul Dev Lalita Chaudhary Deborshi Sharma 《The Indian journal of surgery》2010,72(1):331-332
We report a very rare case of Meckel’s diverticulum with benign stricture presenting as recurrent small bowel obstruction in a malnourished young adult female. Extensive preoperative investigations were unable to diagnose the cause of recurrent obstruction. Segmental small bowel resection with attached diverticulum was performed. 相似文献
90.
Devís-Devís J Peiró-Velert C Beltrán-Carrillo VJ Tomás JM 《Journal of adolescence》2009,32(2):213-231
This study examined screen media time usage (SMTU) and its association with personal and socioeconomic factors, as well as the effect of season and type of day, in a Spanish sample of 12-16 year-old school adolescents (N=323). The research design was a cross-sectional survey, in which an interviewer-administered recall questionnaire was used. Statistical analyses included repeated measures analyses of variance, analysis of covariance and structural equation models. Results showed an average of 2.52h per day of total SMTU and partial times of 1.73h per day in TV viewing, 0.27h per day in computer/videogames, and 0.52h per day in mobile use. Four significant predictors of SMTU emerged. Firstly, the type of school was associated with the three media of our study, particularly students from state/public school spent more time on them than their private schools counterparts. Secondly, older adolescents (14-16 years old) were more likely to use computer/videogame and mobile phone than younger adolescents. Thirdly, the more accessibility to household technology the more probable computer/videogames and mobile phone were used. Finally, boys spent significantly more time in mobile phone than girls. Additionally, results revealed that adolescents seemed to consume more TV and computer/videogames in autumn than in winter, and more TV and mobile phones on weekends than on weekdays, especially among state school students. Findings from this study contribute to the existing knowledge on adolescents' SMTU patterns that can be transferred to families and policies. 相似文献