BACKGROUND:Biliary tract stents comprise two types:expanding metallic stents and plastic stents,the patency time of the former is shorter than the latter,but the cost is higher.Thus,it is dispute which kinds of stent should be selected.Accordingly,it becomes a research topic how to improve patency rate and prolong patency time using cheap stents.OBJECTIVE:To explain the progress of biliary tract stents and to explore the effects of materials and types of biliary tract stents on patency rates and patency times.METHODS:The Chinese Journal Full-text Database and Medline were retrieved by the first author using search terms of "biliary stent,metallic stent,plastic stent,occlusion and stricture" both in Chinese and English.Meta analysis or repetitive studies were excluded.After that,20 documents concerning the effects of materials and types of biliary tract stents on patency rates and patency times were analyzed.RESULTS AND CONCLUSION:Biliary stent implantation is the preferred way for alleviative treatment of malignant obstruction of bile duct with few complications.Biliary tract stents comprise two types comprise metallic stents and plastic stents,the biocompatibility of both stents need to be improved.The metallic stents exhibited advantages in preventing bacteria,maintaining stent patency and reducing complications,but the high cost limited its application.Though plastic stents easily lead to stent occlusion due to bacteria adhesion and biliary siltation,however,it has merits of easy change and cheap cost.The combination of biliary stent implantation and radiotherapy can prolong effective patency period and prevent stent occlusion.The results demonstrated that biliary stent implantation is best methods for treating malignant obstruction of bile duct,and combined biliary stent implantation with radiotherapy can prevent stent obstruction.

The dada of 987 out-patients aged 60 or over,who visited Bajiao Community Health Center of Beijing Shijingshan District from January 2006 to December 2009,were retrospectively analyzed.The results revealed that there was no gender difference in the prevalence of low vision and blindness ( χ2 =2.719,P = 0.606); the severity of low vision and blindness was correlated with the age of patients ( χ2 =138.389,P = 0.000); cataract was the main cause of low vision and blindness,accounting for 49.6%(62/125) of low vision and 64.3% (36/56) of blindness.

Objective To study the rule of breaking Ferula fukanensis seed dormancy under low-temperature and content changes of endo-hormone.Methods The seeds were treated with stratification under 4 ℃ and germinated under 20 ℃.The content of endo-hormone,such as Z,GA_3,IAA,and ABA,was mensurated by HPLC.Results The seed germination rate achieved as high as 14% in 20 d and more than 60% in 40 d.Among breaking the seed dormancy,the content of endo-hormone was decreased gradually,while the rate of GA_3 and ABA was increased quickly in 10—20 d under 4 ℃ stratification.ConclusionThe stratification under 4 ℃ could break the seed dormancy.The rate of GA_3 and ABA is a pivotal factor of the seed dormancy.The endo-hormones IAA and Z have the significant effect on seed germination.

Objective To assess the clinical significance of SAA, IP-10 and PCT in the diagnosis of AECOPD. Methods Sixty AECOPD patients, 52 with sCOPD, and 28 healthy subjects were assigned to three groups. Clinical data and serum specimen were obtained from another 19 AECOPD patients at stable stage as AECOPD-sCOPD group. Serum levels of SAA, IP10 and PCT were quantitatively measured by ELISA. Levels of multiple serum markers were statistically compared among different groups. Results The concentration of SAA significantly differed between the AECOPD and sCOPD groups (P < 0.05), so did the concentration of IP-10 (P < 0.05); no statistical significance was found in terms of serum PCT concentration between the two groups (P > 0.05). Conclusions As compared with the sCOPD group, levels of serum SAA and IP-10 in the AECOPD group were significantly elevated, which is helpful in the diagnosis of AECOPD with a sensitivity and specificity of 100% and 54.9%for SAA, and 96.1%and 75.0%for IP-10. However, PCT level failed to identify AECOPD from sCOPD.

BACKGROUND: In the tissue engineering studies, the common method of cell detachment is trypsinization. However, this method may decrease cell activity by breaking the extracellular matrix proteins. Therefore, it is important to develop a new cell detachment method which can avoid the damage from trypsinization.OBJECTIVE: Based on that poly N-isopropylacrylamide (PNIPAAm) could alter its hydrophobic property with the change of temperature, this study aimed to develop a novel method which can control cell detachment by simply changing the temperature. METHODS: IPAAm was dissolved in isopropanol with final concentration of 55% (w/v). IPAAm solution was evenly laid on the surface of TCPS dish, and PNiPAAm was then covalently grafted on the TCPS dish surface by electron beam irradiation. The micro.structure of the surface of TCPS dish was observed by atomic force microscopy (AFM) before and after PNIPAAm grafted. Water contact angle was determined by sessile drop method. And an inverted phase contrast microscope was used to observe and evaluate the cell detachment ability of PNIPAAm grafted TCPS dish by subjecting the same dish to different temperatures. RESULTS AND CONCLUSION: AFM images showed that a thin and compact PNIPAAm layer formed on the TCPS dish surface. In the water contact angle test, there was no statistic difference between PNIPAAm grafted and ungrafted surfaces at 37 ℃, and the water contact angle of PNIPAAm grafted surfaces was lower than that of ungrafted surface at 20 ℃. The cells adhered to the surface of the PNIPAArn grafted TCPS dish at 37 ℃, which would be detached at 20 ℃.It was successful to control cell detachment by simply changing the temperature with PNIPAAm grafted TCPS dish, and it would be promising to be applied in tissue engineering.

BACKGROUND:Self-assembling short-peptide has been shown to be a kind of hovel nanometer biomaterial.Following culture combined with chondrocytes,self-assembling short-peptide can promote eell marex secretion,cell division and proliferation.and eell phenotype maintenance.For this reason,it has become a candidate for all ideal cell scaffold used for cartilage tissue engineering.OBJECTIVE:To observe the biological characteristics of rabbit articular chondrocytes cultured in three-dimensional nanoscale self-assembling short.peptide KLD-12 hydrogel seaffold.DESIGN.TIME AND SETTING:An observational experiment was performed at the laboratory of Institute for Nanobiomedical Technology and Membrane Biology,Sichuan University between November 2007 and April 2008.MATERIALS:Nanoscale short-peptide KLD-12 with a sequence of Ac-KLDLKLDLKLDL-CONH2 was synthesized by Shanghai Biotech Company,China.METHODS:Chondrocytes were harvested from New Zealand rabbit articular cartilage by enzyme digestion.Following in vitro culture.chondrocytes of passage 3 were inoculated into 4 g/L self-assembling short-peptide KLD-12 solution at a density of 5x 109/L.Peptide gel formation was induced by phosphate buffered saline for three-dimensional culture.MAIN OUTCOME MEASURES:①Observation of chondrocyte morphology in the short-peptide hydrogel with inverted phase contrast microscope.②Detection of intracellular matrix secretion by toluidine blue staining and immunohistochemistry.③Measurement of mRNA expression levels of aggrccan,type Ⅱ collagen and type Ⅰ collagen in chondrocyte-seeded hydrogels by reverse transcription-polymerase chain reaction.RESULTS:①The viability of chondrocytes digested and isolated from rabbit articular cartilage was over 95%.④Chondrocytes cultured in three-dimensional short-peptide hydrogel maintained their round shape,proliferated actively,and aggregated in clusters.In addition.cartilage lacuna could be seen surrounding the clusters.③Both toluidine blue staining and type Ⅱ collagen immunohistochemistry results were positive.The mRNA expression levels of aggrecan and type Ⅱ collagen were increased with time.④Reverse transcription-polymerase chain reaction results revealed that after 3 weeks of in vitro culture in the short-peptide hydrogel,chondrocytes maintained the capability to secrete aggrecan and to express type Ⅱ collagen.CONCLUSION:Self-assembling short-peptide KLD-12 three-dimensional hydrogel Call well inainrain the normal cellular morphology,function and proliferative capability of chondrocytes

Nineteen patients with low rectal cancer underwent laparoscopy-assisted anterior resection with prolapsing technique for sphincter preservation.The clinical data were retrospectively reviewed.Fecal continence was preserved successfully in all patients.There was no perioperative mortality,only two cases with anastomotic leak and one case with local recurrences.Laparoscopy-assisted anterior resection with a prolapsing technique for low rectal cancer is safe procedure and can be an alternative sphincter-preserving operation.

Two peaks were present in the NRA annual curve of Panax quinquefolius. A high peak appeared in late April and a smaller peak occured in early July. It is important to apply N2 fertilizers just before the appearance of the two peaks. Experiment on the effect of different light and pH showed that higher NRA were formed at 4000 Lx and pH 4.3～6.0.

0.05). PET/CT was more sensitive than B ultrasound and mammography in diagnosing axillary disease(P

Objective To explore the difference of immunological characteristics between recombination human granulocyte colony-stimulating factor(rhG-CSF)mobilized peripheral blood grafts(G-PB)and steady-state bone marrow grafts(SS-BM).Methods From April to October 2003,G-PB and SS-BM of 15 related donors were collected.T cell subgroups,dendritic cells(DC),monocytes and the expression of CD28 costimulatory molecules on T cells were determined by multicolor flow cytometry.The lymphocyte proliferation ability and the quantities of interleukin-4(IL-4)and interferon-?(IFN-?)secreted by T cells were determined using MTT assays and sandwich ELISA.Results The absolute numbers of monocytes,CD3+,CD4+ and CD8+ T cells,and the ratios of CD4/CD8 in G-PB were significantly higher than those in SS-BM,respectively(P0.05).The quantities of IFN-? and IL-4 secreted by T cells per micromilter in G-PB was significantly higher than those in SS-BM(P0.05).The absolute numbers of DC1 and DC2 in G-PB were significantly higher than those in SS-BM(P0.05).Conclusion It is concluded that the difference of immunological characteristics between G-PB and SS-BM may explain the lower incidence of GVHD and lower relapse rate after SS-BM and G-PB transplantation.