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排序方式: 共有1854条查询结果,搜索用时 11 毫秒
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Jenny U. Johansson Nathaniel S. Woodling Qian Wang Maharshi Panchal Xibin Liang Angel Trueba-Saiz Holden D. Brown Siddhita D. Mhatre Taylor Loui Katrin I. Andreasson 《The Journal of clinical investigation》2015,125(1):350-364
Microglia, the innate immune cells of the CNS, perform critical inflammatory and noninflammatory functions that maintain normal neural function. For example, microglia clear misfolded proteins, elaborate trophic factors, and regulate and terminate toxic inflammation. In Alzheimer’s disease (AD), however, beneficial microglial functions become impaired, accelerating synaptic and neuronal loss. Better understanding of the molecular mechanisms that contribute to microglial dysfunction is an important objective for identifying potential strategies to delay progression to AD. The inflammatory cyclooxygenase/prostaglandin E2 (COX/PGE2) pathway has been implicated in preclinical AD development, both in human epidemiology studies and in transgenic rodent models of AD. Here, we evaluated murine models that recapitulate microglial responses to Aβ peptides and determined that microglia-specific deletion of the gene encoding the PGE2 receptor EP2 restores microglial chemotaxis and Aβ clearance, suppresses toxic inflammation, increases cytoprotective insulin-like growth factor 1 (IGF1) signaling, and prevents synaptic injury and memory deficits. Our findings indicate that EP2 signaling suppresses beneficial microglia functions that falter during AD development and suggest that inhibition of the COX/PGE2/EP2 immune pathway has potential as a strategy to restore healthy microglial function and prevent progression to AD. 相似文献
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J R Parikh H Venkatakrishna-Bhatt G M Panchal 《American journal of industrial medicine》1987,12(4):439-443
Blood histamine levels were measured by the bioassay of histamine (on an isolated strip of guinea pig ileum) in workers exposed to cotton dust in a textile mill in Ahmedabad. Byssinotic subjects showed very high levels of blood histamine as compared to nonbyssinotic and control subjects. The blood histamine levels were not well correlated to the dust concentrations or duration of exposure but rather to the day of the week (ie, first, second, third, etc., after weekend break) on which the samples were collected. The blood histamine levels were high on the first day of the work week, when byssinotics complained most of their symptoms. 相似文献
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Bela Prajapaty Bharat Shah 《Indian journal of otolaryngology and head and neck surgery》1997,49(4):391-393
The pyriform sinus fistula is rare congenital anomaly of either third or fourth branchial pouch, which most frequently presented itself by recurrent episodes of neck abscess for long time. Majority of patients with this anomaly presented with symptoms before 10 years and it is more common than has previously been commonly found on leftside (93%). Clinically high index of suspicion, cannulation of the tract under general anaesthesia, Direct laryngoscopy and fistulogram have freequently been successful in identifying the presence of these embryological remnants. Surgical exploration of sinus tract with its total excision, guided with cannula inside its lumen is the definitive treatment. 相似文献
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Dhawan Subhash; Puri Raj K.; Kumar Ashok; Duplan Helen; Masson Jean-Michel; Aggarwal Bharat B. 《Blood》1997,90(4):1535-1544
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BACKGROUND CONTEXT: Intramedullary fat-containing benign childhood tumors of the cord include lipomas, dermoid cysts, and teratomas. These are embryonal tumors. Most intramedullary fat-containing tumors are solitary. Multiple intramedullary lipomas are rare and may represent a spinal lipomatous malformation. The presence of another intramedullary dermoid tumor in the same case is rare. PURPOSE: The intent of this case report is to look at magnetic resonance features and possible mechanisms of association of these fat-containing intramedullary tumors. STUDY DESIGN/SETTING: A 3-year-old male child presented with spastic quadriplegia. METHODS: Magnetic resonance imaging (MRI) of spine was done on a 1.5-T scanner in different planes. RESULTS: MRI showed multiple intramedullary spinal lipomas with an intramedullary dermoid involving the conus, cord atrophy, and subarachnoid fat droplets. CONCLUSION: Multiple intramedullary lipomas with an intramedullary dermoid represent a form of spinal lipomatous malformation. Both may represent embryogenic mesenchymal inclusions and hamartomatous growth, which can be accurately diagnosed with MRI. 相似文献
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HIV seroincidence among patients at clinics for sexually transmitted diseases in nine cities in the United States 总被引:1,自引:0,他引:1
Weinstock H Dale M Gwinn M Satten GA Kothe D Mei J Royalty J Linley L Fridlund C Parekh B Rawal BD Busch MP Janssen RS 《Journal of acquired immune deficiency syndromes (1999)》2002,29(5):478-483
Although the numbers of newly reported diagnoses of AIDS decreased in the 1990s, it is not clear whether they reflect a decreasing number of new HIV infections. Direct measurement of HIV incidence through follow-up cohort studies is difficult and costly. We estimated HIV incidence and trends in incidence among men who have sex with men (MSM) and heterosexual men and women at clinics for sexually transmitted diseases (STDs) by using a recently developed serologic testing algorithm that requires only a single blood specimen. Cross-sectional anonymous serosurveys were conducted at 13 STD clinics in nine cities in the United States from 1991 through 1997. Before anonymous HIV testing, demographic and clinical information was abstracted. Of 129,774 specimens tested, 362 (0.28%) were from persons estimated to be recently infected. Incidence among MSM was 7.1% (95% confidence interval (CI): 4.8-10.3), 14 times higher than that among heterosexuals, which was 0.5% (CI: 0.4- 0.7). Incidence among MSM and heterosexuals remained unchanged during the time studied. Decreasing rates of new AIDS diagnoses in the 1990s do not reflect stable rates of new HIV infections among MSM and heterosexual patients attending these clinics. 相似文献