This paper deals with the regularity of the changes in 'serum specific IgM and IgG, and the relationship between the antibody level and infected worm stage of Brugia malayi.The jirds (Meriones unguiculatus) and BALB/cCR mice infected with three different methods were used in the experiment.The antibody level in BALB/cCR mice after infection was higher than that in jirds.The occurrence of IgM in infected jirds and mice was earlier than that of IgG,reached its peak at 4-8th week, and maintained a certain level during 30 weeks.The responses of IgM and IgG were considered as an immunological characteristic of parasitic helminth infection probably.

0.05,group 1 or group 2 vs group 3 P

s〕 Objective:To investigate the influence of repeated firings on the color of porcelain fused to metal crown(PFM) . Methods: 5 PFM samples were prepared and fired for 9 times.The color of the samples was measured following firing with CIE1976 L*a*b* color system . The color difference ?E ab *,hue angle h ab * and chroma C ab * were calculated according to the following calculations:?E ab * ={(?L*) 2 +(?a*) 2 +(?b*) 2} 1/2 , C ab * ={(a*) 2+(b*) 2} 1/2 , h ab *=tg 1 b*/ a*, L* presented brightness. Results: After repeated firing, L* value of PFM , C ab * and L* value of dentin layer and h ab * value of opaque layer increased. Conclusion: The color of PFM after repeated firing may become brighter. The color change is resulted from the increase of L* and C ab * of dentin layer.

Objective: To study the influence of repeated firings on the PFM bond strength. Methods: 25 specimens of PFM in the diameter of 13.0 mm and thickness of (1.0?0.02) mm were prepared and fired at 920 ℃ for 1, 3, 5, 7 or 9 times(5 samples for each time). The remained porcelain rate(RPR) was measured by Mackert method and used to evaluate the bond strength.Results: After 3 firings, the RPR of PFM decreased obviously, and additional firings had no obvious effect on the RPR. Conclusion: 3 times firing or more may decrease the bond strength of PFM.

Objective To investigate the possibility of human umbilical cord blood mesenchymal stem cells' migrating to the gastric carcinoma xenografts. Methods Gastric cancer cells SGC-7901 were injected subcutaneously into one side of the inguinal groove in the hairless mice to establish the animal model.Gastric cancer-bearing mice were divided randomly into two groups and five in each group (n =5). Then mesenchymal stem cells and the fibroblast HFL-Ⅰ labeled with fluorescent dye SP-DiI were injected at the opposite side. Ten days later, the mice were put to death, and the gastric carcinoma xenografts, liver, spleen,lung and the tissue of injected point were obtained. Cryosections from frozen tissues were processed for fluorescent microscopy and the distribution of MSC and fibroblasts in different organs were observed. Adjacent sections were stained with HE. Results Human umbilical cord blood mesenchymal stem cells were mainly distributed in gastric carcinoma xenografts (0.0150±0.0079), but were found only a little in liver (0.0010±0.0005), spleen (0.0015±0.0012), lung (0.0014±0.0008) and injected point (0.0043±0.0039). Fibroblasts were mainly observed in the tissue of injected point, but none in other tissues (P ＜0.01). Conclusion Human umbilical cord blood mesenchymal stem cells have the tendency of migrating to tumor sites, suggesting that it can be hopefully used in the diagnosis and treatment of gastric cancer.

Most pelvic fractures were commonly seen in polytrauma caused by violent forces,and often complicated with hemorrhagic shock,with mortality being 25%～39%.Anti-shock and control of bleeding are th e philosophy of treatment of this critical condition.Since 1985,hundred s of pelvic fracture victims have bee n sal-vaged in my hospital by VIP procedure which means ventilation(V),infusion(I),and pulsation(P).First,V was to establish an airway,then I was to manage hypovolumic shock,and fin ally,P was to improve the impaired heart function to maintain normal hemodynamics and tissue perfusion.It was necessary for antishock therapy to infuse rapidly and sufficiently in o rder to gain diluted blood.Pneumatic antishock garment,angiography an d em-bolism,and retroperitoneal tampon aded bleeding could control most hem orrhage associated with pelvic fractures.[

To reverse drug resistance mediated by the MDR1 gene product P-glycoprotein(P-gp) in tumor cells in a specific manner, a hammerhead ribozymes which can cleave the GUC sequence in codon 196 of MDR1 mRNA was designed and cloned into a recombinant retroviral vector pDOR-neo at BamH I restriction sites and packaged with packaging cell line PA317 cells.The viral supernatant was used to infect the multidrug-resistant human hepatocarcinoma cell line BEL-7402/DOX. After selection with G418,resistant colonies were obtained.Stable expression of retroviruses in both PA317 and infected BEL-7402/DOX cells was confirmed by Northern Blot hybridization. Down-regulation of P-gp and even of MDR1 mRNA was found in BEL-7402/DOX infected with ribozyme construct. The rate of BEL - 7402/DOX infected cell defected by flow cytometric analysis was 8.2 ~ 14.6% while in uninfected cell it was 93 .4 ~ 97.5% . The BEL-7402/ DOX cell infected with ribozyme construct was found back to drug-sensitivity to a series of drugs by MTT colorimetric assay . The results demonstrated that the recombinant retroviral vector expressing ribozyme transfecting human hepatocarcinoma BEL-7402/DOX could inhibit MDR1 gene expression and reverse tumor MDR phenotype back to drug-sensitive condition.

Protein kinase B( Akt)is an intermediate signal molecule in PI3K-Akt-mTOR signaling pathway which plays an important role in development and incidence of colorectal cancer when activated by phosphorylation. As target of drugs,Akt has become a focus in the treatment of colorectal cancer. Clinical trials research proves that many kinds of Akt inhibitors have good antitumor activity. In recent years,the Akt inhibi-tors are more and more be taken seriously in colorectal cancer treatment.

In order to observe the therapeutic effect of acupuncture plus facial paralysis rehabilitative exercise in the treatment of facial paralysis, 49 cases were treated by acupuncture plus facial paralysis rehabilitative exercise, and 45 cases were treated by single acupuncture for comparison. The total effective rate was 91.8% in the former and 62.2% in the latter. There is a significant difference (P ＜ 0.01) in the effective rate between the two groups.

BACKGROUND:Steam sterilization is a commonly used oral clinical method of disinfection, but whether it would produce more significant impact on equipments waiting for sterilization has been controversial.
OBJECTIVE:To investigate the effect of autoclave on two kinds of orthodontic distal end cutters by comparing shearing force and corrosion after sterilization.
METHODS:Tiantian (n=15) and 3M (n=15) distal end cutters commonly used in orthodontic treatment were chosen for testing and divided into three groups, respectively. Three groups for each kind of cutter were treated with high-pressure steam sterilization, steam sterilization+extraoral shear, and steam sterilization+intraoral shear, respectively. The shearing force and metal ography of the distal end cutters were recorded after 0, 20, 40, and 60 cycles of sterilization. An energy dispersive spectrometer was used to scan the surfaces of the working edges of the distal end cutters after 60 cycles.
RESULTS AND CONCLUSION:It was found that with an increase in the number of sterilization cycles, the shear force and extent of corrosion increased in al six groups of distal end cutters, but the situation was worse for Tiantian cutters than for 3M cutters. It was found that the difference of shear force between the Tiantian autoclave group and 3M autoclave group was statistical y significant (P<0.05) after 20, 40, and 60 sterilization cycles. Meanwhile, the metal ography showed that different degrees of discoloration and rust spots appeared on the work edges of the two brands of distal end cutters with an increase in the number of sterilization cycles, but the corrosion of the Tiantian distal-end cutter was more widespread, and even work-edge defects appeared. The carbon content of the Tiantian distal-end cutter was higher than that of the 3M cutter (P<0.05), but the chromium content was higher in the 3M cutter (P<0.05). In addition, aluminum and titanium elements only existed in the 3M cutter. The use of the autoclave affected the distal end cutters in terms of shearing force and corrosion, but the effect on 3M distal end cutters was obviously less than that on Tiantian cutters.