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991.
Lawrence G. Raisz MD 《Clinical reviews in bone and mineral metabolism》2006,4(2):123-127
Prostaglandins, particularly PGE2, have been shown to stimulate bone formation in a number of circumstances. Endogenous prostaglandins may be important in
heterotopic ossification and fracture healing. The major source of prostaglandins in bone is the inducible form of cyclooxygenase
(COX)-2 and inhibition of COX-2 may impair bone formation. Recent studies using selective agonists for the prostaglandin EP2
and EP4 receptors, which stimulate cAMP in bone cells, have suggested that these might be used clinically to accelerate bone
formation, particularly when used locally. 相似文献
992.
Francis Y. Yao MD 《Current hepatitis reports》2006,5(1):14-22
A new era in the treatment of chronic hepatitis B began approximately a decade ago. Three oral nucleoside or nucleotide analogues—lamivudine,
adefovir dipivoxil, and entecavir—are now approved in the United States for the treatment of chronic hepatitis B. Other new
oral agents, including telbivudine, clevudine, and emtricitabine, are in various stages of clinical investigation. This article
reviews the efficacy and resistance data of these oral antiviral agents, and the preliminary results of combination therapy
for chronic hepatitis B. 相似文献
993.
Tom Rossenbacker MD Sheila J. Carroll MD Huajun Liu MD Cuno Kuipri Thomy J.L. de Ravel FCP Koen Devriendt MD PhD Peter Carmeliet MD PhD Robert S. Kass PhD Hein Heidbüchel MD PhD 《Heart rhythm》2004,1(5):611-615
OBJECTIVES: The purpose of this study was to determine the clinical and biophysical characteristics of a novel SCN5A mutation. BACKGROUND: Brugada syndrome and isolated cardiac conduction defect have been linked to SCN5A mutations. METHODS: Eleven members of a western European family underwent electrophysiologic investigations and mutation analysis of the SCN5A gene. Wild-type and mutant SCN5A channels were expressed in HEK293 cells, and whole cell currents were studied using patch clamp procedures. RESULTS: A novel mutation, R376H, in the first pore segment of SCN5A variably causes Brugada syndrome and/or conduction disease in a single family. Biophysical analysis demonstrated a significant current reduction for the mutant, a pathophysiologic profile consistent with Brugada syndrome and isolated cardiac conduction defect. Among 11 family members, 9 were carriers of the mutation. The proband's initial presentation was a saddleback Brugada ECG, atrial flutter, and diffuse conduction disturbances. He had no inducible ventricular arrhythmias but experienced sudden cardiac death. His brother was affected by atrial flutter and had a clear conduction disorder, but he did not display baseline or evocable ECG signs of Brugada syndrome. He received an implantable cardioverter-defibrillator that delivered one appropriate shock after 1 year of follow-up. The phenotype in the family members was highly variable and ranged from noninducible and inducible asymptomatic carriers of the mutations to isolated conduction disease and to symptomatic Brugada syndrome. CONCLUSIONS: We describe the functional characterization of a novel SCN5A pore mutation, R376H, with variable clinical expression in the same family. Differentiating between electrophysiologic entities (Brugada syndrome-isolated cardiac conduction defect) is more challenging. Recognition of factors modifying the clinical presentation may be important for clinical decision making. 相似文献
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Colorectal cancer is one of the most common malignancies in developed countries. Although guaiac-based fecal occult blood
tests have proven their efficacy for screening, they have major drawbacks. Immunochemical fecal occult blood tests are theoretically
superior as they can detect very small amounts of hemoglobin, and they are specific to human hemoglobin. Recently many different
immunochemical tests have been marketed, with variations in hemoglobin detection limit, mechanism of action, sample collection
method, and test development. Molecular tests represent an alternative to fecal blood tests, which have been designed to detect
certain fecal DNA mutations, or aberrant gene methylation (either hyper-or hypomethylation). In this review, we discuss a
selection of the most significant studies published in the last 3 years regarding noninvasive tools for colorectal cancer
screening. 相似文献