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Recently the Liver Transplantation Center of the First Affiliated Hospital,Zhejiang University School of Medicine announced the successful performance of 1021 liver transplants by October 17,2011.At a gathering celebrating this event,experts from the USA and China highly appreciated this achievement made  相似文献   
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Background: Optomap uses the ultra‐wide field scanning laser ophthalmoscopy to provide retinal examination. It permits fundus examination without the use of a mydriatic, which is more comfortable for the patients. This paper determines the sensitivity and specificity of the Optomap for detecting retinal signs under non‐mydriatic conditions. Methods: Fifty‐four eyes identified with retinal/choroidal signs and eight normal eyes were recruited from 31 Hong Kong Chinese subjects. Photo‐documentation of fundal changes was obtained with the Optomap under non‐mydriatic conditions before a dilated fundus examination by a clinician using standard procedures. The eyelid was retracted using a cotton bud when necessary. Dilated fundus examinations were performed by another clinician using binocular indirect ophthalmoscopy and slitlamp biomicroscopy with a fundus lens. The Optomap images were evaluated by four other investigators under masked condition. The International Classification of Disease, Ninth Revision (ICD‐9‐CM) was adopted for recording retinal features. Screening results were compared with those obtained using the dilated fundus examination as the gold standard. Results: The cotton bud method for eyelid retraction showed an improvement in the area of retina that could be visualised. The sensitivity and specificity of the Optomap averaged 76.4 and 71.9 per cent, respectively. Some fundal signs were missed by all observers in the Optomap but not with the biomicroscope. These included white‐without‐pressure, lattice degeneration, paramacular drusen and pigmentary changes at central fundus. Conclusion: Optomap serves as a reliable screening tool for fundus examination especially because it covers a much wider area of the peripheral retina than other digital instruments for fundus photography.  相似文献   
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We investigated the inhibition of IkappaB kinase (IKK) activity in lipopolysaccharide (LPS)-activated murine macrophages (RAW 264.7 cell line) by various polyphenols including (-)-epigallocatechin-3-gallate, theaflavin, a mixture of theaflavin-3 gallate and theaflavin-3'-gallate, theaflavin-3,3'-digallate (TF-3), pyrocyanidin B-3, casuarinin, geraniin, and penta-O-galloyl-beta-D-glucose (5GG). TF-3 inhibited IKK activity in activated macrophages more strongly than did the other polyphenols. TF-3 strongly inhibited both IKK1 and IKK2 activity and prevented the degradation of IkappaBalpha and IkappaBbeta in activated macrophage cells. The results suggested that the inhibition of IKK activity by TF-3 could occur by a direct effect on IKKs or on upstream events in the signal transduction pathway. Furthermore, geraniin, 5GG, and TF-3 all blocked phosphorylation of IKB from the cytosolic fraction, inhibited nuclear factor-kappaB (NFkappaB) activity, and inhibited increases in inducible nitric oxide synthase levels in activated macrophages. These results suggest that TF-3 may exert its anti-inflammatory and cancer chemopreventive actions by suppressing the activation of NFkappaB through inhibition of IKK activity.  相似文献   
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Mercury contents in biological samples can be measured by cold vapor atomic absorption spectroscopy combined with the flow-injection analysis system. However, water vapor in the absorption cell attenuated and distorted the signals. This study described the strategy to overcome this problem by adding an additional gas-liquid separator after the mixing/separator assembly. This modification can efficiently minimize the moisture in the transfer line and in the absorption cell. This improved technique was adopted to study the differential tissue distribution of methylmercury and HgS after oral administration to mice for five consecutive days. The present study suggests that the insoluble HgS (the main constituent of a Chinese mineral drug, cinnabar, used as a sedative) can still be absorbed from gastrointestinal tract and distributed to various tissues including the brain. As compared with methylmercury, the total amount of HgS accumulated in the tissues ranging about one five-thousandth of methylmercury, which is well correlated with the biological activity of HgS reported previously.  相似文献   
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In this study, mercuric chloride was applied to the primary cultures of mouse pancreatic islet cells for studying its effects on resting membrane potential and the intracellular free calcium ion concentration ([Ca 2+), using the techniques of electrophysiology and fluorometry. It was observed that mercuric chloride (1-100 microM) caused a rapid and sustained depolarization, and induced a rapid first phase and a large sustained second phase of elevation in fura-2 fluorescence ratio in islet cells. The depolarization and increased lCa2+]i induced by mercuric chloride could be inhibited by dithiothreitol (a sulfhydryl-containing reducing agent). Removing Ca2+ from the external medium inhibited the mercuric chloride-induced elevation of [Ca2+]i. The increased [Ca2+]i may also originate from the endoplasmic reticulum of pancreatic islet cells, since caffeine (an activator of Ca2+ release from endoplasmic reticulum) and thapsigargin (an inhibitor of endoplasmic reticulum Ca2+-ATPase) could antagonize the effect of mercuric chloride. Moreover, in the absence of glucose in the medium, the response of islet cells to mercuric chloride was a rapid first phase of increased [Ca2+]i followed by a small sustained second phase. Readministration of 5 mM glucose was sufficient but transient to restore sustained phase of increased [Ca2+]i. The increase of [Ca2+]i in islet cells induced by a lower concentration of mercuric chloride (5 microM) was potentiated in higher glucose (7.5 mM) medium. Tolbutamide, an inhibitor of the ATP-sensitive K+-channel, could also inhibit the effect of mercuric chloride. These findings suggest that mercuric chloride initially interacts with the sulfhydryl groups of membrane-bound proteins, which may be an ATP-sensitive K+ channel, to cause depolarization of the islet cells. This depolarization triggers Ca2+ influx and then the release of Ca2+ from the endoplasmic reticulum.  相似文献   
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