By the way of searching engines and finding website linkages, the author retrieved the domestic and foreign medical ethics information resources on internet,enumerated some main websites related to medical ethics, analyzed the present condition,and suggested that we should hasten the construction of medical ethics information resources on internet.

Objective To analyze sampling frequency and grid density frequency on the computed radiography(CR)system and to develop an effective method to suppress or eliminate grid artifacts.Methods To test grids with different grid-density in combination with IP boards of different specifications. Radiographic images with various qualities were obtained by simulating two kinds of signaling frequencies (namely two kind of grids with different grid densities),and utilizing three kinds of sampling frequencies (6,8,10 pixels/mm).A variety of different simulation images were obtained.Results By comparing simulation images with actual images,it was discovered that correct signaling frequency could be achieved if the sampling frequency were equal to twice the signaling frequency.The obtained image was clear and free of grid artifact.A grid density of

Interventional techniques not only provide opportunity of treatment for many diseases,but also alter the traditional therapeutic pattern.With the new century of wide application of biological therapies, interventional technique also shows extensive roles.The current biological therapy,including gene therapy, cell transplantation therapy,immunobiologic molecule therapy containing cell factors,tumor antibody or vaccine,recombined proteins,radioactive-particles and targeting materials therapy,can be locally administrated by interventional techniques.The combination of targeting biological therapies and high-targeted interventional technique holds advantages of minimal invasion,accurate delivery,vigorous local effect,and less systemic adverse reactions.Authors believe that the biological therapy may arise a great opportunity for interventional radiology,therefore interventional colleagues should grasp firmly and promptly for the development and extension in this field.(J Intervent Radiol,2007,16:73-74)

OBJECTIVE: 1H-NMR (Nuclear Magnetic Resonance Method) was used to quantitatively determine the MePEG (me-thoxy polyethylene glycol) content and chain density on MePEG-PLGA-NP surface, and study the influences of MePEG molecular weights and proportion on the chemical and physical properties of MePEG-PLGA-NP surface. METHODS: MePEG-PLGA-NP were prepared by self-emulsion solvent diffusion method with methoxy polyethylene glycol-poly(lactic acid-hydroxyl acid) copolymer (Me-PEG-PLGA) as the carriers. And the particle average size and Zeta potential were characterized. 1H-NMR method were used to ascertain the composition of the MePEG-PLGA copolymer and determine the MePEG content and chain density on the MePEG-PLGA-NP surface, and compared with colorimetric assay. RESULTS: The composition of MePEG-PLGA copolymer are basically the same with the labelled amount. When the Molecular weight is at the same, along with the increase of proportion of MePEG, the average size of MePEG-PLGA-NP decrease, the absolute value of the Zeta potential also decrease gradually, MePEG content on particles surface (α) increase gradually, the MePEG chain density on nanoparticles surface (δ) increase gradually, the distance between two adjacent MePEG chains on the surface of the particles (D) decrease; When there is the same proportions, with MePEG chain length increases, nanoparticles are not significantly different on the particle average size and the Zeta potential, whereas α increase gradually, the δ decreases, and D increases; Theavalue of the same MePEG-PLGA-NP determined by colorimetric assay is higher than which is determined by 1H-NMR. CONCLUSION: 1H-NMR method can be used to quantitatively determine the MePEG content and chain density on MePEG-PLGA-NP surface; Compared with the traditional method, the results determined by 1H-NMR method are more accurate. With the experimental limits, MePEG molecular weighs and proportion have influences on the chemical and physical properties of MePEG-PLGA NP surface, such as mean size, Zeta potential and the MePEG content and chain density on nanoparticles surface. Copyright 2012 by the Chinese Pharmaceutical Association.

Atherosclerosis ; Endothelial Cells ; Humans ; Nitric Oxide Synthase Type III ; Stem Cells

To effectively search the AIDS information resource on internet,the author enumerates main websites and makes classification in practical way.Through analyzing and comparison,the suggestion of strengthen the construction of AIDS information resource is given in the paper.

Diabetic retinopathy is one of the most common and serious microvascular complications of diabetes, and it is a very complex pathological process, displaying multi-factor, multi-stage characteristic in the outcome. Recent studies have shown that the pathogenesis of diabetic retinopathy is closely related to oxidative stress, and antioxidant therapy can effectively improve the condition. Heme oxygenase-1(HO-1)is a widely existing antioxidant defense enzyme, which can reduce the injury caused by oxidative stress and plays an important physiological role. Studies have indicated that in retina HO-1 can be highly induced by hyperglycemia. Moreover, the expression level of HO-1 by man-made changes can accelerate or postpone the diseases progression. That means HO-1 for the diagnosis and treatment of diabetic retinopathy has satisfactory applied foreground. In this article we would like to review the role of HO-1 in diabetic retinopathy.

Backgroud EDTA is an important calcium chelator,commonly used as an ophthalmic additive,its role in promoting corneal penetration of drug may facilitate transepithelial corneal collagen crosslinking.However,there were few reports about the penetration of riboflavin to corneal stroma enhanced by EDTA both home and abroad.Objective To determine the concentrations of riboflavin in corneal intrastromal under different interventions using high-performance liquid chromatography (HPLC).To ensure the efficacy and safety of 0.5％ EDTA in riboflavin penetrating to corneal stroma by the transepithelial procedures.Methods Fifteen New Zealand white rabbits were randomized into three groups,corneal epithelium of 5 rabbits were debrided,corneal epithelium of another 5 rabbits were left in situ and 0.5％ EDTA-Na2 was topically applied for 1 hour,and the corneal epithelium of last 5 rabbits were just left in situ,after those procedures 0.1％ riboflavin + 20％ dextran was applied topically to the corneas for 30 minutes(1 drop every 3 minutes).Then,the epithelium in the corneas of EDTA and epi-situ group were carefully removed before all the corneas were punched with an 8.5 mm diameter blade and homogenized subsequently.Ultimately,the riboflavin concentrations were determined by HPLC.Results After treated with riboflavin for 30minutes,the mean concentration of riboflavin in the epi-removed group was (23.54± 1.61)μg/g tissue,the EDTA group was (2.04 ±0.25)μg/g tissue and the epi-situ group was (1.44 ±0.06)μg/g tissue,showing significant difference among them (F =1792.839,P =0.000).There were statistically significant differences between any two groups (t =41.780,7.484,43.408,all at P ＜ 0.05).However,the riboflavin concentration of other two groups were failed to meet the theoretical value 15 μg/g tissue,excepted for epi-removed group.Conclusions The diffusion of riboflavin to the corneal stroma can be fully enhanced by removing the epithelium preoperatively,penetration enhancer EDTA can effectively promote the penetration of riboflavin to the cornea,but it still can not replace the role of removing epithelium on the penetration of riboflavin to the cornea.

Child ; Child, Preschool ; Female ; Humans ; Infant ; Infant, Newborn ; Male ; Respiratory Tract Diseases ; diagnostic imaging ; Tomography, Spiral Computed ; methods

Objective To evaluate the efficacy of a self-expandable metal stent coated with autologous endothelial progenitor cells(EPCs)for prevention of restenosis in transjugular intrahepatic portosystemic shunt(TIPS)in a swiue model.Methods EPCs were coated on the metal stents using fibrin gel before TIPS procedure.TIPS was performed in 15 young adult pigs,using an autologous EPC-seeded stent(treatment group,n=9)or a conventional bare metal stent(control group,n=6).All pigs were sacrificed at 2 weeks after TIPS procedure.Portography was performed immediately before the euthanasia.Gross and microscopic pathological exams and immunohistochemical exams of the TIPS track specimens were performed.Fisher test and t test were used to analyse the data.Results TIPS was performed successfully in all the 15 swine.On day 14 of follow-up,direct portography and necropsy demonstrated that 5 shunts remained patent,2 shunts stenosed,and the remaining 2 shunts occluded in the treatment group(n=9);while 5 shunts were occluded and one shunt was stenotic in the control group(n=6).The patency rate was 56%vs 0(P=0.03)between the two groups.Histological analyses showed a greater pseudo-intimal hyperplasia in the TIPS track of the control group than that of the treatment group(pseudointimal thickness at hepatic vein,hepatic parenchyma and portal vein site was(1.2±0.4),(1.3±0.5),(1.5±0.4)mmvs(1.0±0.6),(0.9±0.5),(1.0±0.4)mm respectively(P＜0.05).Conclusion The EPC-coated metal stent is feasibly constructed in vitro and improves the patency in TIPS in a porcine model.