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Primary liver cancer, the major histology of which is hepatocellular carcinoma (HCC), is the second leading cause of cancer death worldwide. We comprehensively examined recent international trends of primary liver cancer and HCC incidence using population-based cancer registry data. Incidence for all primary liver cancer and for HCC by calendar time and birth cohort was examined for selected countries between 1978 and 2012. For each successive 5-year period, age-standardized incidence rates were calculated from Volumes V to XI of the Cancer Incidence in Five Continents (CI5) series using the online electronic databases, CI5plus. Large variations persist in liver cancer incidence globally. Rates of liver cancer remain highest in Asian countries, specifically in the East and South-East, and Italy. However, rates in these high-risk countries have been decreasing in recent years. Rates in India and in most countries of Europe, the Americas and Oceania are rising. As the population seroprevalence of hepatitis B virus (HBV) continues to decline, we anticipate rates of HCC in many high-risk countries will continue to decrease. Treatment of hepatitis C virus (HCV) is likely to bring down rates further in some high-rate, as well as low-rate, countries with access to effective therapies. However, such gains in the control of liver cancer are at risk of being reversed by the growing obesity and diabetes epidemics, suggesting diabetes treatment and primary prevention of obesity will be key in reducing liver cancer in the longer-term.  相似文献   
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Ruggieri  PM; Laub  GA; Masaryk  TJ; Modic  MT 《Radiology》1989,171(3):785-791
The technique and feasibility of magnetic resonance (MR) angiography of intracranial vessels were studied in 35 healthy volunteers. Variations in image orientation, repetition time (TR), and flip angle were evaluated to determine their effects on flow-related enhancement. Gradient modifications--including echo time (TE), motion compensation, bandwidth, and field of view--were also studied in an effort to reduce motion-induced phase shifts. Results indicated that a FISP (fast imaging with steady precession) sequence with a TR of 50 msec, TE of 15 msec, velocity compensation in the read and section-select directions, acceleration compensation in the read direction, anisotropic volume, and a 1.25-mm partition thickness produced three-dimensional angiographic MR images that were accurate and reproducible in the depiction of the major intracranial vessels. Difficulties with field of view, persistent signal void secondary to higher-order motion, and spatial resolution remain major problems requiring additional study.  相似文献   
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Reduction of bacterial adherence to catheter surface with heparin   总被引:1,自引:0,他引:1  
Despite many advances in catheter design and use, the most common cause of hospital-acquired infections is catheterization of the urinary tract. In the present investigation the adherence of bacteria to catheters coated with heparin was studied. Since heparin itself does not coat the plastic catheter surface, a complex of heparin with tridodecylmethylammonium chloride (TDMAC) was used which results in hydrophobic association of hydrocarbon chains of the TDMAC with the catheter leaving the quaternary ammonium moiety of TDMAC exposed to the surface forming ionic bonds with the highly anionic sulfate groups of heparin. Coating latex catheter material with TDMAC without heparin resulted in 3.6-fold higher adherence whereas coating with the TDMAC-heparin complex reduced adherence to less than 10% of control untreated latex. TDMAC-heparin also significantly reduced bacterial adherence to teflon coated latex (Bardex) and vinyl catheter material. Less than 30% of the original heparin was removed after wash periods of up to one week. These results indicate that TDMAC-heparin coating of urethral catheters reduces bacterial adherence and thereby may delay the acquisition of catheter associated urinary tract infection.  相似文献   
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BACKGROUND: We tested the hypothesis that using a subgluteus approach to the sciatic nerve requires a lower concentration of mepivacaine to obtain complete anesthesia as compared with the popliteal approach. METHODS: With midazolam premedication (0.05 mg kg(-1) iv), 48 patients undergoing hallux valgus repair were randomly allocated to receive a sciatic nerve block using either a posterior popliteal (group Popliteal, n = 24) or subgluteus (group Subgluteus, n = 24) approach with 30 mL of local anesthetic injected after elicitation of plantar flexion of the foot with a current 相似文献   
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M R Ruggieri  P M Hanno  R M Levin 《Urology》1987,29(5):534-537
It has been recently suggested that nitrofurantoin may induce symptoms of interstitial cystitis by acting as a surface active agent that destroys glycosaminoglycan (GAG) on the bladder surface. Evidence accumulated over the past decade has demonstrated that the bladder surface GAG prevents bacterial adherence. In this experiment, exposure of the bladder lumen to nitrofurantoin at more than twice the therapeutic concentration did not destroy the bladder GAG layer (as evidenced by periodic acid-Schiff histochemistry) nor increase bacterial adherence as did a true surface active agent (Triton X-100). Acid treatment as well as all tested organic solvents except 50% dimethyl sulfoxide (DMSO) also removed the bladder GAG layer and increased bacterial adherence. These results indicate that neither nitrofurantoin nor 50% DMSO has adverse effects on the bladder surface and thus is unlikely to initiate the interstitial cystitis symptom complex by means of surfactant activity.  相似文献   
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