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941.
CT-guided needle biopsy is a common procedure for obtaining a tissue diagnosis and consequently correctly managing patients. This procedure has many potential complications, ranging from simple pneumothorax or self-limiting hemoptysis to life-threatening pulmonary hemorrhage and air embolism. Though the latter is a rare complication of CT-guided needle biopsy, it has attracted a lot of interest. We report a case of right coronary air embolism resulting in myocardial infarction after a CT-guided percutaneous needle biopsy of the lung.  相似文献   
942.
Cardiac resynchronization therapy (CRT) devices not only deliver effective treatment but may also serve as valuable diagnostic tools in heart failure management. In the present study, the minutes of daily physical activity and heart rate variability, measured by sensors incorporated into such a device, reflected the effects of CRT and were related to New York Heart Association functional class.  相似文献   
943.
Hydroxymethylglutaryl coenzyme-A reductase inhibitors, or statins, have been shown to decrease mortality rates in patients who have coronary artery disease. It has been postulated that part of the mortality benefit conferred by statins is due to a decrease in ventricular arrhythmias. We assessed the effect of statin therapy on recurrent ventricular arrhythmias in 281 patients who developed coronary artery disease after implantable cardioverter-defibrillator placement. Statin therapy was associated with a significant decrease in the risk of ventricular arrhythmia that would require implantable cardioverter-defibrillator therapy.  相似文献   
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Deregulated phosphatidylinositol 3-kinase (PI3K) signaling pathway is widely implicated in tumor growth and resistance to chemotherapy. While a strong rationale exists for pharmacological targeting of PI3K, only a few proof-of-principle in vivo efficacy studies are currently available. PWT-458, pegylated-17-hydroxywortmannin, is a novel and highly potent inhibitor of PI3K in animal models. Upon in vivo cleavage of its poly(ethyleneglycol) (PEG), PWT-458 releases its active moiety 17-hydroxywortmannin (17-HWT), the most potent inhibitor in its class. Here we show that a single intravenous injection of PWT-458 rapidly inhibited PI3K signaling, as measured by a complete loss of AKT (Ser-473) phosphorylation in xenograft tumors grown in nude mice. Following a daily X5 dosing regimen, PWT-458 demonstrated single-agent antitumor activity in nude mouse xenograft models of U87MG glioma, nonsmall cell lung cancer (NSCLC) A549, and renal cell carcinoma (RCC) A498. Efficacious doses ranged from 0.5 mg/kg to 10 mg/kg, achieving a superior therapeutic index over 17-HWT. PWT-458 augmented anticancer efficacy of a suboptimal dose of paclitaxel against A549 and U87MG tumors. Combination treatment of PWT-458 and an mTOR inhibitor, Pegylated-Rapamycin (Peg-Rapa), resulted in an enhanced antitumor efficacy in U87MG. Finally, PWT-458 in combination with interferon-alpha (Intron-A) caused a dramatic regression of RCC A498, which was not achieved by either agent alone. These studies identify PWT-458 as an effective anticancer agent and provide strong proof-of-principle for targeting the PI3K pathway as novel anticancer therapy.  相似文献   
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Increasing allergy potency of Zinnia pollen grains in polluted areas   总被引:1,自引:0,他引:1  
There is much evidence that allergic symptoms represent a major health problem in polluted cities. The aim of this research is to elucidate some microscopic effects of air pollutants on pollen structure, proteins, and allergenicity. A scanning electron microscopy study of pollen grains indicated that in polluted areas, airborne particles accumulate on the surface of pollen grains and change the shape and tectum of pollen. Also, many vesicles are released from polluted pollen grains and the pollen material agglomerates on the surface of pollen grains. SDS-PAGE revealed that different proteins exist in mature and immature pollen grains. There were no significant differences between protein bands of polluted and nonpolluted pollen grains, but in polluted pollen, protein content decreases in response to air pollution, causing the release of pollen proteins. The results indicate that mature pollen have more allergenicity than immature pollen. According to the experiments polluted pollen grains are more effective than nonpolluted pollen grains in inducing allergic symptoms. Air pollutants can cause allergic symptoms, but when associated with allergen pollen grains, their allergenicity power is increased.  相似文献   
950.
To determine the feasibility and effectiveness of treatments for depressed elderly medical inpatients, MEDLINE was searched for potentially relevant articles published from January 1987 to August 1997, using the keywords "depression or depressive disorder" (exploded) and "aged." The bibliographies of relevant articles were searched for additional references. Fifteen reports met the following inclusion criteria: (a) published in English or French; (b) minimum age criterion of 55 and over or mean age 65 and over; (c) subjects admitted to the medical service of an acute care hospital; (d) used accepted criteria for depression; (e) examined treatment(s) for depression; and (f) reported outcomes as a depression diagnosis and/or symptom level. Information was abstracted independently from each article by two reviewers, tabulated, and compared. The limited evidence suggests contraindications to treatment in 38% to 87% of subjects who received a heterocyclic antidepressant compared to 4% of subjects who received the selective serotonin reuptake inhibitor (SSRI) fluoxetine; rates of discontinuation and study completion were similar for heterocyclics, the SSRIs, and psychostimulants. All of the treatments (including social support/psychotherapy) appeared to be at least modestly effective in the short term.  相似文献   
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