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排序方式: 共有717条查询结果,搜索用时 15 毫秒
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Avner Adini Irit Adini Etty Grad Yuval Tal Haim D. Danenberg Peter M. Kang Benjamin D. Matthews Robert J. DAmato 《International journal of molecular sciences》2021,22(10)
Myocardial infarction (MI) remains the leading cause of death in the western world. Despite advancements in interventional revascularization technologies, many patients are not candidates for them due to comorbidities or lack of local resources. Non-invasive approaches to accelerate revascularization within ischemic tissues through angiogenesis by providing Vascular Endothelial Growth Factor (VEGF) in protein or gene form has been effective in animal models but not in humans likely due to its short half-life and systemic toxicity. Here, we tested the hypothesis that PR1P, a small VEGF binding peptide that we developed, which stabilizes and upregulates endogenous VEGF, could be used to improve outcome from MI in rodents. To test this hypothesis, we induced MI in mice and rats via left coronary artery ligation and then treated animals with every other day intraperitoneal PR1P or scrambled peptide for 14 days. Hemodynamic monitoring and echocardiography in mice and echocardiography in rats at 14 days showed PR1P significantly improved multiple functional markers of heart function, including stroke volume and cardiac output. Furthermore, molecular biology and histological analyses of tissue samples showed that systemic PR1P targeted, stabilized and upregulated endogenous VEGF within ischemic myocardium. We conclude that PR1P is a potential non-invasive candidate therapeutic for MI. 相似文献
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DV Beard PL Molina KE Muller KM Denelsbeck BM Hemminger JR Perry MP Braeuning DH Glueck WD Bidgood M Mauro 《Canadian Metallurgical Quarterly》1995,197(3):753-758
PURPOSE: Interpretation time of serial staging chest CT cases, which each contained current and previous examinations, with a simple prototype workstation called filmstack was experimentally compared with interpretation time with a film alternator. MATERIALS AND METHODS: The filmstack displayed a "stack" of sections for each examination; user controls allowed rapid selection of preset attenuation windows and both synchronized and unsynchronized scrolling. Eight radiologists were timed as they used the filmstack and the film alternator to interpret four ergonomically complex serial CT cases. RESULTS: All reports dictated on the basis of findings with filmstack and film were of acceptable clinical accuracy. The time to examine a case with filmstack was significantly faster than the time with film, including the time to load and unload the alternator (99% confidence [P = .01]). There was no statistically significant difference in interpretation time between filmstack and prehung film. CONCLUSION: Use of a low-cost stacked CT workstation with a single 1,024 x 1,024 monitor is an effective means of interpreting cases that require comparison of multiple CT examinations. 相似文献
15.
We reviewed 410 cases, 365 males and 45 females, mean age 64 years, of inguinal and femoral hernia, from 1/1/1991 to 31/12/1994, repaired with Lichtenstein and Trabucco techniques. Recurrent hernias repaired were 36 (8,8%). Local anesthesia was used in 82% and follow-up has ranged from 6 months to 4 years. The meshes used are made with a single layer of polipropylene and the Trabucco plugs T1 were made by hand at the operating table. In our experience these two techniques are simple, but is very important, before application of the mesh, a correct dissection of inguinal region. We made a complete excision of cremasteric fibers preservig, if possible, the genital branch of the genitofemoral nerve. The transversalis fascia is introflected and sutured in direct hernia repair or when there are a loss of tissues. The preliminary results obtained with the "tension free" hernioplasty are satisfying. The most important complications were 9 hematomas and an important and persistent inguinal neuralgia in 1 case. There were no recurrences, but we must considered the short follow-up period. 相似文献
16.
MD Ercegovac N Vojvodi? Soki?DV SM Jankovi? J Drulovi? N Stojsavljevi? Z Levi? 《Canadian Metallurgical Quarterly》1998,126(9-10):335-344
CONCLUSION: We conclude that despite inevitable variability the clinical picture of JME is characteristic. It is easy to diagnose JME if one thinks of it while the history should be thoroughly analyzed. An EEG recording during sleep confirms the diagnosis. An early diagnosis of JME permits adequate prognosis of the subsequent course of epilepsy, and adequate therapy brings remission in most of the patients. If treatment starts following the large number of severe GTC seizures, the response to therapy is incomplete. The persistency of the illness throughout the life, the need for continuous medication and therapeutic unresponsiveness in cases with late diagnosis, do not justify the increasing misconception that JME is of benign nature. Diagnosis of JME is rare because of insufficient familiarily of physicians with the illness. BACKGROUND: Juvenile myoclonic epilepsy (JME) is an idiopathic generalized epileptic syndrome characterized with the combination of myoclonic, generalized tonic-clonic (GTC) and absence seizures that are readily provoked by sleep deprivation. PATIENTS: Forty-three patients, aged from 14 to 51 years, participated in a 5-year follow-up study. Diagnosis was made according to the criteria (Table 1) for diagnosis of JME set by Panayiotopoulos et al. (1994). Nineteen patients made their first contact with a neurologist at the Institute of Neurology and were diagnosed as JME, while the remaining 24 were referred to from other medical institutions with a diagnosis of therapy resistant to focal epilepsy. All patients underwent a somatic and neurological examination, "mini mental test," EEG in waking and CT scan of the brain. Some patients had EEG performed during sleep and some had MRI of the head. RESULTS: JME began between 9 and 26 (average 17) years. All patients had myoclonic seizures, 98% had GTC and 23% absence seizures. The first myoclonic seizure occurred between 9 and 24 years while the frst GTC seizure occurred between 10 and 32 years. Myoclonic seizures (83% of patients) and GTC seizures (70% of patients) occurred most often immediately after awaking. The most frequent provocative factors were insufficient sleep, alcohol abuse and tiredness. Epilepsy in the family was present in 39%, focal neurological deficiency in 9% and pathological findings on of CT and MRI in 7% of patients. Waking EEG was pathological in 77% of patients; it included generalized spike-wave discharges in 73%, multiple spike-wave complexes in 33% and focal discharges in 12% of patients, respectively. In all 26 patients tested, sleep EEG was pathological most often with multiple spike-wave complexes in 85% and 3-4 Hz spike-wave complexes in 57% of patients. The correct diagnosis of JME following a comprehensive examination was made in 24 (56%) patients after a delay of 1 to 35 years. In 24 patients with delayed diagnosis of JME the replacement of earlier medication with valproic acid (VPA) induced remission in 18 patients (75%) while 1 patient (4%) experienced a reduction in the number of seizures. Five patients (21%) did not respond to VPA medication: 2 due to a weak compliance, another 2 due to inefficient medication and 1 because of the preexistent malabsorption syndrome. In 19 patients (44%) with initial diagnosis of JME, VPA was introduced immediately upon diagnosis. Of them, 15 (79%) had excellent response to VPA, 1 refused therapy and for 3 patients there is no information. In 2 patients VPA was substituted due to side effects (hepatotoxicity and alopetia) with lamotrigine (low doses), which brought about decrease in frequency and mitigation in myoclonic seizures. 相似文献
17.
Paired-pulse plasticity is typically used to study the mechanisms underlying synaptic transmission and modulation. An important question relates to whether, under physiological conditions in which various opposing synaptic properties are acting in parallel, the net effect is facilitatory or depressive, that is, whether cells further or closer to threshold. For example, does the net sum of paired-pulse facilitation (PPF) of excitatory postsynaptic potentials (EPSPs), paired-pulse depression (PPD) of inhibitory postsynaptic potentials (IPSPs), and the hyperpolarizing slow IPSP result in depression or facilitation? Here we examine how different time-dependent properties act in parallel and examine the contribution of gamma-aminobutyric acid-B (GABAB) receptors that mediate two opposing processes, the slow IPSP and PPD of the fast IPSP. Using intracellular recordings from rat CA3 hippocampal neurons and L-II/III auditory cortex neurons, we examined the postsynaptic responses to paired-pulse stimulation (with intervals between 50 and 400 ms) of the Schaffer collaterals and white matter, respectively. Changes in the amplitude, time-to-peak (TTP), and slope of each EPSP were analyzed before and after application of the GABAB antagonist CGP-55845. In both CA3 and L-II/III neurons the peak amplitude of the second EPSP was generally depressed (further from threshold) compared with the first at the longer intervals; however, these EPSPs were generally broader and exhibited a longer TTP that could result in facilitation by enhancing temporal summation. At the short intervals CA3 neurons exhibited facilitation of the peak EPSP amplitude in the absence and presence of CGP-55845. In contrast, on average L-II/III cells did not exhibit facilitation at any interval, in the absence or presence of CGP-55845. CGP-55845 generally "erased" short-term plasticity, equalizing the peak amplitude and TTP of the first and second EPSPs at longer intervals in the hippocampus and auditory cortex. These results show that it is necessary to consider all time-dependent properties to determine whether facilitation or depression will dominate under intact pharmacological conditions. Furthermore our results suggest that GABAB-dependent properties may be the major contributor to short-term plasticity on the time scale of a few hundred milliseconds and are consistent with the hypothesis that the balance of different time-dependent processes can modulate the state of networks in a complex manner and could contribute to the generation of temporally sensitive neural responses. 相似文献
18.
Cavallaro S Torrisi L Cutroneo M Amato A Sarta F Wen L 《The Review of scientific instruments》2012,83(6):063305
In this paper a very sensitive ion collection device, for diagnostic of laser ablated-target plasma, is described. It allows for reducing down to few microvolts the signal threshold at digital scope input. A standard ion collector is coupled to a transimpedance amplifier, specially designed, which increases data acquisition sensitivity by a gain ≈1100 and does not introduce any significant distortion of input signal. By time integration of current intensity, an amount of charge as small as 2.7 × 10(-2) pC can be detected for photopeak events. 相似文献
19.
We propose a new technique combining dynamic and static analysis of programs to find linear invariants. We use a statistical tool, called simple component analysis, to analyze partial execution traces of a given program. We get a new coordinate system in the vector space of program variables, which is used to specialize numerical abstract domains. As an application, we instantiate our technique to interval analysis of simple imperative programs and show some experimental evaluations. 相似文献
20.
Approximate similarity retrieval with M-trees 总被引:4,自引:0,他引:4
Pavel Zezula Pasquale Savino Giuseppe Amato Fausto Rabitti 《The VLDB Journal The International Journal on Very Large Data Bases》1998,7(4):275-293
Motivated by the urgent need to improve the efficiency of similarity queries, approximate similarity retrieval is investigated
in the environment of a metric tree index called the M-tree. Three different approximation techniques are proposed, which
show how to forsake query precision for improved performance. Measures are defined that can quantify the improvements in performance
efficiency and the quality of approximations. The proposed approximation techniques are then tested on various synthetic and
real-life files. The evidence obtained from the experiments confirms our hypothesis that a high-quality approximated similarity
search can be performed at a much lower cost than that needed to obtain the exact results. The proposed approximation techniques
are scalable and appear to be independent of the metric used. Extensions of these techniques to the environments of other
similarity search indexes are also discussed.
Received July 7, 1998 / Accepted October 13, 1998 相似文献