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排序方式: 共有243条查询结果,搜索用时 15 毫秒
1.
MR compatibility of Guglielmi detachable coils   总被引:6,自引:0,他引:6  
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2.
Adverse reaction to intravenous gadoteridol   总被引:1,自引:0,他引:1  
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3.
Thirty-five plants are listed, which are used by traditional healers in the central and southern parts of Somalia. For each species are listed: the botanical name with synonyms, collection number, vernacular name, medicinal use, preparation of remedy and dosage. Results of a literature survey are also reported including medicinal use, substances isolated and pharmacological effects.  相似文献   
4.
Patellofemoral joint: kinematic MR imaging to assess tracking abnormalities   总被引:4,自引:0,他引:4  
Shellock  FG; Mink  JH; Fox  JM 《Radiology》1988,168(2):551-553
The patellofemoral joint was imaged with magnetic resonance (MR) in the axial plane while the knee was positioned from 0 degrees to 32 degrees of flexion (nine positions). These multiple sequential images obtained within the early phases of flexion of the knee were viewed in a "cine-loop" format, producing a kinematic study that clearly demonstrated the relationship of the patella to the trochlear groove. Four healthy subjects and one patient with known bilateral subluxing patellae were studied. The preliminary results suggest that kinematic MR imaging of the patellofemoral joint is potentially useful for the evaluation of patellar tracking abnormalities.  相似文献   
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6.
As a remedy for environmental pollution, a simple synthesis approach has been developed to prepare nitrogen doped carbon quantum dot/magnetite nanocomposites (Fe3O4@NCQDs NCs) using non-toxic and cost effective lemon juice as precursor for removal of organic dye pollutant. Fe3O4@NCQDs NCs were characterized by using UV-Vis spectroscopy, FTIR, XRD, FESEM, EDS, TEM, VSM and TGA/DTA. TEM results show spherical shaped Fe3O4@NCQDs NCs with an average particle size of 5 nm. Batch adsorption studies were done to investigate the tendency of the nanocomposites to remove representative methyl blue (MB) dye from aqueous solution. The effects of MB dye concentration, dosage of Fe3O4@NCQDs NC adsorbent, pH, contact time and temperature were optimized by varying one variable while all the other parameters were kept constant. The experiment showed rapid removal of MB dye within 20 minutes with an adsorption efficiency of over 90.84% under optimum conditions. The adsorption process fits the Freundlich isotherm model well with R2 and n values of 0.993 and 1.842, respectively, at 298 K indicating the feasibility of the adsorption process. The adsorption process is spontaneous and involves exothermic behaviour as confirmed by thermodynamic studies. From a kinetic study, it was found that the pseudo-second order model is more suitable to describe the adsorption process than the pseudo-first order model for adsorption of MB dye onto Fe3O4@NCQDs NCs.

Herein, we report the green synthesis of magnetic, nitrogen doped carbon quantum dot/Fe3O4 NPs using aqueous lemon extract for the efficient removal of organic dye pollutants from contaminated water.  相似文献   
7.
Retroviral-mediated gene transfer is the most attractive modality for gene transfer into hematopoietic stem cells. However, transduction efficiency has been low using amphotropic Moloney murine leukemia virus (MoMLV) vectors. In this study, we investigated modifications of gene transfer using amphotropic MoMLV vectors in cell-free supernatant for their ability to increase the currently low transduction of both committed hematopoietic progenitors, granulocyte-macrophage colony- forming units (CFU-GMs), and their precursors, long-term culture- initiating cells (LTC-IC). First, based on the observation that bone marrow cells express more gibbon ape leukemia virus (GALV) receptor (Glvr-1) than amphotropic receptor (Ram-1), PG13/LN, which is a MoMLV vector pseudotyped with the GALV envelope, was compared with the analogous amphotropic envelope vector (PA317/LN). Second, progenitor cell transduction efficiency was compared between CD34 enriched and nonenriched progenitor populations. Third, the duration of transduction in vitro was extended to increase the proportion of progenitor cells that entered cell cycle and could thereby integrate vector cDNA. In 20 experiments, 1 x 10(6) marrow or peripheral blood mononuclear cells (PBMCs)/mL were exposed to identical titers of pseudotyped PG13/LN vector or PA317/LN vector in the presence of recombinant human interleukin-1 (IL-1), IL-3, IL-6, and stem cell factor (SCF; c-kit ligand) for 5 days. 50% of fresh vector supernatant was refed daily. Hematopoietic progenitor cells as measured by G418-resistant granulomonocytic colony (CFU-GM) formation were transduced more effectively with PG13/LN (19.35%) than with PA317/LN (11.5%, P = .012). In 11 further experiments, enrichment of CD34 antigen positive cells significantly improved gene transfer from 13.9% G418-resistant CFU-GM in nonenriched to 24.9% in CD34-enriched progenitor cells (P < .01). To analyze gene transfer after extended growth factor-supported long-term culture, 1 x 10(6) marrow cells/mL were cultured with IL-1, IL-3, IL-6, and SCF (50 ng/mL each) for 1, 2, and 3 weeks. Fifty percent of PG13/LN supernatant with growth factors was refed on 5 days per week. Five percent of marrow CFU-GM and 67% of LTC-IC were G418 resistant at 1 week (n = 4), 60% of CFU-GM and 100% of LTC-IC were resistant at 2 weeks (n = 2) and 74% of CFU-GM (n = 4) and 82% of LTC-IC (n = 2) were resistant at three weeks.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
8.
Hereditary Spastic Paraplegias (HSP) encompass a clinically and genetically heterogeneous group of neurodegenerative disorders characterized by insidiously progressive weakness and spasticity of the lower extremities. We describe a consanguineous Saudi family segregating a complicated form of HSP in an autosomal recessive pattern. The two affected siblings had early onset, cognitive, speech and motor involvement with spasticity of the lower extremities. Their upper extremities were mildly hypertonic. An intronic splice acceptor site mutation in ERLIN2 was found to be responsible for causing this disorder found in this family. ERLIN2 is a mediator of endoplasmic reticulum degradation pathway (ERAD) which helps to remove the aberrant proteins. Our results, in concurrence with previous studies suggest that alteration in ERLIN2 is one of the causes of complicated HSP, thereby increasing the spectrum of known mutations in SPG18.  相似文献   
9.
The genetic susceptibility to acquiring low high density lipoprotein‐cholesterol (LHDLC) levels is not completely elucidated yet. In this study, we performed a common variant association study for harboring this trait in ethnic Arabs. We employed the Affymetrix high‐density Axiom Genome‐Wide ASI Array (Asian population) providing a coverage of 598,000 single nucleotide variations (SNPs) to genotype 5495 individuals in a two‐phase study involving discovery and validation sets of experiments. The rs1800775 [1.31 (1.22–1.42); p = 3.41E‐12] in the CETP gene and rs359027 [1.26 (1.16–1.36); p = 2.55E‐08] in the LMCD1 gene were significantly associated with LHDLC levels. Furthermore, rs3104435 [1.26 (1.15–1.38); p = 1.19E‐06] at the MATN1 locus, rs9835344 [1.16 (1.08–1.26); p = 8.75E‐06] in the CNTN6 gene, rs1559997 [1.3 (1.14–1.47); p = 9.48E‐06] in the SDS gene and rs1670273 [1.2 (1.1–1.31); p = 4.81E‐06] in the DMN/SYNM gene exhibited suggestive association with the disorder. Seven other variants including rs1147169 in the PLCL1 gene, rs10248618 in the DNAH11, rs476155 in the GLIS3, rs7024300 in the ABCA1, intergenic rs10836699, rs11603691 in P2RX3 and rs750134 in CORO1C gene exhibited borderline protective properties. Validation and joint meta‐analysis resulted in rs1800775, rs3104435 and rs359027 retaining their predisposing properties, while rs10836699 and rs11603691 showed protective properties. Our data show several predisposing variants across the genome for LHDLC levels in ethnic Arabs.  相似文献   
10.
In 2012, Tigray orthohantavirus was discovered in Ethiopia, but its seasonal infection in small mammals, and whether it poses a risk to humans was unknown. The occurrence of small mammals, rodents and shrews, in human inhabitations in northern Ethiopia is affected by season and presence of stone bunds. We sampled small mammals in two seasons from low- and high-density stone bund fields adjacent to houses and community-protected semi-natural habitats in Atsbi and Hagere Selam, where Tigray orthohantavirus was first discovered. We collected blood samples from both small mammals and residents using filter paper. The presence of orthohantavirus-reactive antibodies in blood was then analyzed using immunofluorescence assay (human samples) and enzyme linked immunosorbent assays (small mammal samples) with Puumala orthohantavirus as antigen. Viral RNA was detected by RT-PCR using small mammal blood samples. Total orthohantavirus prevalence (antibodies or virus RNA) in the small mammals was 3.37%. The positive animals were three Stenocephalemys albipes rats (prevalence in this species = 13.04%). The low prevalence made it impossible to determine whether season and stone bunds were associated with orthohantavirus prevalence in the small mammals. In humans, we report the first detection of orthohantavirus-reactive IgG antibodies in Ethiopia (seroprevalence = 5.26%). S. albipes lives in close proximity to humans, likely increasing the risk of zoonotic transmission.  相似文献   
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