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排序方式: 共有1432条查询结果,搜索用时 15 毫秒
31.
32.
Roaa S. Gassas Ahmed N. Absi Abdulrahman A. Alghamdi Ahmed S. Alsaeed Sameer M. Alamoudi Ihab Y. Hemaidi Majed D. Alahmadi Walaa A. Rajkhan Mannar M. Khalil Saleem K. Dadah Ahmed S. Higazi Amani S. Ahmed 《Saudi medical journal》2021,42(8):847
Objectives:To assess local epidemiology and risk factors for bacterial, fungal, and viral infections among the autologous bone marrow transplant population.Methods:This study is a retrospective correlational cohort design comprising 150 adult patients who underwent autologous transplants at Princess Noorah Oncology Center, Jeddah, Saudi Arabia between 2014 and 2020.Results:The study findings indicate that bacterial infection prevalence differed significantly across the different disease status pre-salvage as patients with the relapsed disease were more likely to have bacterial infections. The median of engraftment days differed significantly between those who had a bacterial infection and those who did not. Interestingly, previous pneumonia infection had a positive relationship with the number of hospital stays.Conclusions:Bacterial infections are the dominant type of infection among the autologous patient population. The research reflects authentic practice and reports unique characteristics of autologous transplant patients in terms of the prevalence and types of infection these patients experience. 相似文献
33.
Faisal Saleem Abdul Rehman Farhan Ahmad Asif Hussain Khoja Farhan Javed Kui Zhang Adam Harvey 《RSC advances》2021,11(44):27583
Methane is the main component of biogas, which could be used as a renewable energy source for electricity, source of heat, and biofuel production after upgrading from biogas. It also contains toxic compounds which cause environmental and human health problems. Therefore, in this work, the removal of a toxic compound (toluene) from methane gas was studied using a dielectric barrier discharge (DBD) reactor. It was observed that the removal of the toxic compound could be achieved from methane carrier gas using a dielectric barrier discharge reactor, and it depends on plasma input power. The maximum removal of the toxic compound was 85.9% at 40 W and 2.86 s. The major gaseous products were H2 and lower hydrocarbons (LHC) and the yield of these products also increases with input power. In the current study, the yield of gaseous products depends on the decomposition of toxic compounds and methane, because the decomposition of methane also produces H2 and lower hydrocarbons. The percentage yield of H2 increases from 0.43–4.74%. Similarly, the yield of LHC increases from 0.56–7.54% under the same reaction conditions. Hence, input power promoted the decomposition of the toxic compound and enhanced the yield of gaseous products.The removal of toluene as a toxic volatile organic compound from methane gas, which is the major component of biogas, is carried out using a non-thermal plasma dielectric barrier discharge reactor. 相似文献
34.
Shahroz Saleem Muhammad Irfan Muhammad Yasin Naz Shazia Shukrullah Muhammad Adnan Munir Muhammad Ayyaz Abdullah Saeed Alwadie Stanislaw Legutko Jana Petr Saifur Rahman 《Materials》2022,15(10)
This study investigated the production of Cu2+-doped CoFe2O4 nanoparticles (CFO NPs) using a facile sol−gel technique. The impact of Cu2+ doping on the lattice parameters, morphology, optical properties, and electrical properties of CFO NPs was investigated for applications in electrical devices. The XRD analysis revealed the formation of spinel-phased crystalline structures of the specimens with no impurity phases. The average grain size, lattice constant, cell volume, and porosity were measured in the range of 4.55–7.07 nm, 8.1770–8.1097 Å, 546.7414–533.3525 Å3, and 8.77–6.93%, respectively. The SEM analysis revealed a change in morphology of the specimens with a rise in Cu2+ content. The particles started gaining a defined shape and size with a rise in Cu2+ doping. The Cu0.12Co0.88Fe2O4 NPs revealed clear grain boundaries with the least agglomeration. The energy band gap declined from 3.98 eV to 3.21 eV with a shift in Cu2+ concentration from 0.4 to 0.12. The electrical studies showed that doping a trace amount of Cu2+ improved the electrical properties of the CFO NPs without producing any structural distortions. The conductivity of the Cu2+-doped CFO NPs increased from 6.66 × 10−10 to 5.26 × 10−6 ℧ cm−1 with a rise in Cu2+ concentration. The improved structural and electrical characteristics of the prepared Cu2+-doped CFO NPs made them a suitable candidate for electrical devices, diodes, and sensor technology applications. 相似文献
35.
Asad Ur Rehman Khan Muhammad Ramzan Muhammad Faisal Iqbal Muhammad Hafeez Mohammed M. Fadhali Hamoud H. Somaily Muhammad Javid Muhammad Waqas Mukhtar Muhammad Farooq Saleem 《Materials》2022,15(22)
Zinc sulfide (ZnS) thin films with variable structural, optical, electrical, and thermoelectric properties were obtained by changing the source-to-substrate (SSD) distance in the physical-vapor-thermal-coating (PVTC) system. The films crystallized into a zinc-blende cubic structure with (111) preferred orientation. The films had a wide 3.54 eV optical band gap. High-quality homogenous thin films were obtained at 60 mm SSD. The sheet resistance and resistivity of the films decreased from 1011 to 1010 Ω/Sq. and from 106 to 105 Ω-cm, when SSD was increased from 20 mm to 60 mm, respectively. The phase and band gap were also verified by first principles that were in agreement with the experimental results. Thermoelectric characteristics were studied by using the semi-classical Boltzmann transport theory. The high quality, wide band gap, and reduced electrical resistance make ZnS a suitable candidate for the window layer in solar cells. 相似文献
36.
Saleem AB Longden KD Schwyn DA Krapp HG Schultz SR 《The Journal of neuroscience》2012,32(5):1634-1642
Many animals estimate their self-motion and the movement of external objects by exploiting panoramic patterns of visual motion. To probe how visual systems process compound motion patterns, superimposed visual gratings moving in different directions, plaid stimuli, have been successfully used in vertebrates. Surprisingly, nothing is known about how visually guided insects process plaids. Here, we explored in the blowfly how the well characterized yaw optomotor reflex and the activity of identified visual interneurons depend on plaid stimuli. We show that contrary to previous expectations, the yaw optomotor reflex shows a bimodal directional tuning for certain plaid stimuli. To understand the neural correlates of this behavior, we recorded the responses of a visual interneuron supporting the reflex, the H1 cell, which was also bimodally tuned to the plaid direction. Using a computational model, we identified the essential neural processing steps required to capture the observed response properties. These processing steps have functional parallels with mechanisms found in the primate visual system, despite different biophysical implementations. By characterizing other visual neurons supporting visually guided behaviors, we found responses that ranged from being bimodally tuned to the stimulus direction (component-selective), to responses that appear to be tuned to the direction of the global pattern (pattern-selective). Our results extend the current understanding of neural mechanisms of motion processing in insects, and indicate that the fly employs a wider range of behavioral responses to multiple motion cues than previously reported. 相似文献
37.
Silverman EP Sapienza CM Saleem A Carmichael C Davenport PW Hoffman-Ruddy B Okun MS 《NeuroRehabilitation》2006,21(1):71-79
Respiratory symptoms are recognized as sequelae of motor dysfunction in idiopathic Parkinson's disease (IPD) and these symptoms have the potential to cause problems with swallow, cough, voice and speech. Specifically, maneuvers that require rapid activation and coordination of upper airway and chest wall musculature become progressively impaired as motor dysfunction progresses during the natural course of the disease. This study reports on the maximum inspiratory and expiratory pressures produced by 28 participants (average age 64) diagnosed with moderate to severe IPD (average stage 2.5 with a range of 2.0-3.0). All measures were collected during the "medication on" state. Outcomes of a specific respiratory muscle strength training technique for improving maximum expiratory pressure are reported for three of the patients in this study. Techniques that focus on strengthening the respiratory muscles in patients with IPD (other than with low load breathing exercises), have not been previously reported. The results of this pilot study demonstrate that respiratory muscle weakness may be an important factor in the respiratory complications in IPD and that respiratory muscle strength training has the potential to improve expiratory muscle strength for this population. This improvement has the potential to positively impact high forced respiratory activities, such as forced breathing maneuvers, swallow, cough and speech functions that require greater magnitude and duration of expiration. 相似文献
38.
Quasar Saleem Padiath Achal Kumar Srivastava Sanghmitra Roy Satish Jain Samir Kumar Brahmachari 《American journal of medical genetics. Part B, Neuropsychiatric genetics》2005,(1):124-126
We report a three generation Indian pedigree with the proband having 45 repeats at the Machado Joseph Disease (MJD)/spinocerebellar ataxia 3 (SCA3) disease locus. The proband exhibited clinical features of SCA and showed signs of cerebellar and brainstem atrophy on the MRI scan. The 45 repeat allele was unstable upon inter-generational transmission and was associated with a haplotype found in the majority of MJD/SCA3 patients from around the world. This is the smallest unstable allele reported till date at the MJD/SCA3 locus and may greatly reduce the gap between normal and pathological repeat ranges. This article contains supplementary material, which may be viewed at the American Journal of Medical Genetics website at http://www.interscience.wiley.com/jpages/0148-7299:1/suppmat/index.html. 相似文献
39.
The nucleus accumbens (NAc) plays an important role in both appetitive and consummatory behavior. To examine how NAc neurons encode information during reward consumption, we recorded the firing activity of rat NAc neurons during the performance of a discriminative stimulus task. In this task, the animal must make an operant response to an intermittently presented cue to obtain a sucrose reward delivered in a reward receptacle. Uncued entries to the receptacle were not rewarded. Both excitations and inhibitions during reward consumption were observed, but substantially more neurons were inhibited than excited. These excitations and inhibitions began when the animal entered the reward receptacle and ended when the animal exited the receptacle. Both excitations and inhibitions were much smaller or nonexistent when the animal made uncued entries into the reward receptacle. In one set of experiments, we randomly withheld the reward in some cued trials that would otherwise have been rewarded. Excitations and inhibitions were of similar magnitude whether or not the reward was delivered. This indicates that the sensory stimulus of reward does not drive these phasic responses; instead, the reward-associated responses may be driven by the conditioned stimuli associated with reward, or they may encode information about consummatory motor activity. Another population of NAc neurons was excited on exit from the reward receptacle. Many of these excitations persisted for tens of seconds after the receptacle exit and showed a significant inverse correlation with the rate of uncued operant responding. These findings are consistent with a contribution of NAc neurons to both reward consummatory and reward seeking behavior. 相似文献
40.
An entomological survey for sand flies was conducted at an area of cutaneous leishmaniasis—El-Nekheil in Northeast Al-Madinah
Al-Munawwarah, Saudi Arabia. Standardized sampling with Centers for Disease Control (CDC) light traps and sticky traps was
employed to determine monthly trends in species composition, density, sex ratio, and reproductive status and Leishmania infection rate of vector sand flies. A total of 621 sand flies were collected from March 2006 to November 2007. Six species
representing two genera were identified, three Phlebotomus species: P. papatasi, P. sergenti, and P. bergeroti; and three Sergentomyia species: S. antennata, S. sergenti, and S. shewtzi. Phlebotomus papatasi was the predominant anthropophagic species found and comprised more than 70% of the sand fly population. A population peak
(June) was observed for this species. The density of P. papatasi intra-domiciliary was higher than extra-domiciliary stations and inflated by a greater proportion of female flies. Of 189
dissected Phlebotomus females, 43% were blood-fed. No Leishmania parasites were found. The proportion of gravid P. papatasi increased progressively during the 5-month period from May to September and averaged 38%. Proportions of gravid flies may
be a valid indicator of the physiological age and epidemiologic importance of the vector sand fly population at this focus. 相似文献