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581.
Atypical mycobacterium is rarely seen as a cause of chronic mastoiditis but has been increasingly recognized over the past few years. Mycobacterium abscessus is the most pathogenic and chemotherapy-resistant, rapid-growing mycobacterium of all the four groups. This paper presents a case of a 57-year-old woman who had chronic mastoiditis with recurrent exacerbations. The initial computed tomography (CT) findings showed the presence of an inflammatory process and she was treated with the appropriate antibiotics. The patient subsequently underwent a tissue biopsy when she presented with another exacerbation. At this time, the CT scan did not identify the ongoing exacerbation, but the Gallium-67 scintigraphy did.  相似文献   
582.
Acute ischemic stroke causes a high rate of deaths and permanent neurological deficits in survivors. Current interventional treatment, in the form of enzymatic thrombolysis, benefits only a small percentage of patients. Brain ischemia triggers mobilization of innate immunity, specifically the complement system and Toll-like receptors (TLRs), ultimately leading to an exaggerated inflammatory response. Here we demonstrate that intravenous immunoglobulin (IVIG), a scavenger of potentially harmful complement fragments, and C1-esterase inhibitor (C1-INH), an inhibitor of complement activation, exert a beneficial effect on the outcome of experimental brain ischemia (I) and reperfusion (R) injury induced by transient occlusion of middle cerebral artery in mice. Both IVIG and C1-INH significantly and in a dose–responsive manner reduced brain infarction size, neurological deficit and mortality when administered to male mice 30 min before ischemia or up to 6 h after the onset of reperfusion. When combined, suboptimal doses of IVIG and C1-INH potentiated each other’s neuroprotective therapeutic effects. Complement C3 and TLR2 signals were colocalized and significantly greater in brain cells adjacent to infracted brain lesions when compared to the corresponding regions of the contralateral hemisphere and to control (sham) mice. Treatment with IVIG and C1-INH effectively reduced deposition of C3b and downregulated excessive TLR2 and p-JNK1 expression at the site of I/R injury. Taken together, these results provide a rationale for potential use of IVIG and C1-INH, alone or in combination with ischemic stroke and other neurological conditions that involve inappropriately activated components of the innate immune system.  相似文献   
583.
An efficient and elegant assembly of pyrene/aryl fused pyrrolo[2,3-b]quinolinone and pyrrolizino[3,2-b]quinolinone hybrid heterocycles was achieved via a domino multicomponent reaction strategy using a solid state melt reaction (SSMR) condition. The 1,3-dipole component was generated in situ from N-methylgylcine/l-proline and isatin, while the Baylis–Hillman adduct prepared from pyrene-1-carbaldehyde and various benzaldehydes is used as the dipolarophile. The domino protocol comprises 1,3-dipolar cycloaddition and a consequent double annulation reaction process. The advantages of this cascade protocol include environmentally friendly conditions, the avoidance of toxic organic solvents, simple work-up and good to excellent product yields.

An efficient and elegant assembly of pyrene/aryl fused pyrrolo[2,3-b]quinolinone and pyrrolizino[3,2-b]quinolinone hybrid heterocycles was achieved via a domino multicomponent reaction strategy using a solid state melt reaction (SSMR) condition.  相似文献   
584.
Lycopersene is a stable and safe triterpenoid. Lycopersen had utilized as an antioxidant, antimutagenic, antiproliferative, cytotoxicity, antibacterial and pesticide. Obtaining pure Lycopersene from natural sources is very important for fundamental research and the above applications. The present overview provides an up-to-date and comprehensive summary of the various methods used for extraction, isolation and purification of Lycopersene from natural sources with its applications in food, cosmetics and pharmaceutical fields. Many different extraction methods ranging from conventional techniques (e.g. Soxhlet extraction, Maceration and Rotary evaporator) and other advanced extraction technologies (e.g. Solid-phase microextraction, steam distillation with Clevenger, Clevenger apparatus, Chromatography on SiO2 column, centrifuge, sonication) had been used to obtain Lycopersene from flora and fauna. Purification techniques, alone or in combination, have been investigated for isolation and purification of Lycopersene from crude extracts in various natural sources. The review of Lycopersene identified cap areas like purity and application in various fields.  相似文献   
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Recent technological advances in the medical field have increased the plausibility of exposing humans to high-intensity wavelength radiations like x-rays and gamma rays while diagnosing or treating specific medical maladies. These radiations induce nucleotide changes and chromosomal alterations in the exposed population, intentionally or accidentally. A radiological investigation is regularly used in identifying the disease, especially by the technicians working in intensive care units. The current study observes the genetic damages like chromosomal abnormalities (CA) in clinicians who are occupationally exposed to high-intensity radiations (x-rays) at their workplaces using universal cytogenetic tools like micronucleus assay (MN), sister chromatid exchange and comet assay. The study was conducted between 100 exposed practitioners from the abdominal scanning, chest scanning, cranial and orthopedic or bone scanning department and age-matched healthy controls. We observed a slightly higher rate of MN and CA (p < .05) in orthopedic and chest department practitioners than in other departments concerning increasing age and duration of exposure at work. Our results emphasize taking extra precautionary measures in clinical and hospital radiation laboratories to protect the practitioners.  相似文献   
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