objective: To study the properties of keepers treated with different methods. Methods: Eighteen Z 3 magnetic attachments were divided into three groups at random. Cobalt chromium alloy was used for root cap. The keepers in the first group were cast to the caps, those in the second group were welded to the caps by Nd:YAG laser welding apparatus. Keepers in the third group were untreated. Universal testing machine was adopted to measure the breakaway retention of the attachments. The roughness of keeper surfaces was measured by roughness tester. Results: No statistical difference was observed as to the breakaway retention between magnetic attachments and laser welded coping keeper or between those and cast coping keepers. But retention of the keepers in the two groups was slightly lower than that of untreated keepers. Defects of pits were found on the surfaces of the cast coping keepers. The surface smoothness of the cast coping keepers was inferior to that of the laser welded coping keepers. Conclusion: Laser welded keepers and cast coping keepers can meet clinical demands for the use of magnetic attachments.

Objective To synthesize a new reagent, 1-(6-bromo-2-benzothiazolyl)-3-(5-bromo-8-quinolyl)-triazene (BBTBQT) and apply to the determination of cobalt. Methods The reagent had been synthesized by diazotization and coupling reaction. After purification and characterization, BBTBQT was tested for its color reaction conditions with cobalt in the presence of cetylpyridinium bromide (CPB). Results In the presence of borax buffer solution at pH value of 9.0, the reagent reacted with cobalt to form a blue stable complex with a molar ratio of 2∶1; the complex had a maximum absorption at 640 nm. The apparent molar absorptivity of the complex is 1.55 ?105 L/(mol?cm). Beer’s law was obeyed in the range of 0-0.28 mg/L for cobalt. The method had been applied to determine cobalt in drainage sediment and vitamin B12 injection solution with a mean relative error of 1.9%-5.8% and a standard relative deviation of 1.7%-3.8%. Conclusion The present method is selective, sensitive, accurate, convenient and suitable for determination of trace cobalt in the samples.

Objective To evaluate the performance of community health institutions of Pudong new district.Methods According to the criteria of the Ministry of Health of China,the performance evaluation system appropriate for local area was developed.A cross-sectional survey was conducted at 44 community health centers,and data was analyzed using descriptive statistics,correlation coefficients and multi-factor linear regression.Results The average score of total performance of these 44 community health centers was 78.53.The average scoring rate for institution management,public health service,basic medical care service,CTM service,and comprehensive satisfaction was 68.49％,89.09％,63.51％,87.80％,76.32％,respectively.Degree of informationization (0.477),regional location (0.331) and participating in medical consortia(-0.309)had significant impact on the total performance.Degree of informationization(0.302)and pilots for family doctors(0.301)had significant impact on the basic medical service performance.Conclusion There is a tremendous room for performance improvement for community health institutions in Pudong.Regional location and degree of informationization were the most crucial factors affecting the performance,irrelevant to institutional sizes.Proposals were raised for strengthening the construction of informationization,expanding pilots for family doctors,perfecting the mechanism of medical consortia.

AIM: Bone morphogenetic protein (BMP) as polyphenic morphogen can induce the formation of bone and cartilage. This study investigates the effect of BMP on articular cartilage regeneration after periosteal graft. METHODS: Experiments were performed at the Animal Laboratory (absl-3) of Weifang People's Hospital from September 2006 to January 2007. Sixteen New Zealand white rabbits (32 knees) (2.5-3.0 kg) were divided into experimental and control groups randomly, each 8 rabbits (16 knees). The 3.5 mm in diameter of full-thickness articular cartilage defect was made on femoral intercondylar fossa in all rabbits, and 3.5 mm in diameter of periosteum was cut out from the anteromedial part of the upper tibial bone. In the experimental group, the cartilage defect was covered with periosteum, into which 20 ?g BMP and 20% Pluronic were injected. In the control group, the cartilage defect was covered with periosteum, into which the same dosages of 9 g/L saline and 20% Pluronic were injected. All the rabbits were sacrificed in 4, 8 and 12 weeks postoperatively. Motion of joint, conjunction of repair tissue and perienchyma were examined macroscopically. Haematoxylin-eosin staining and toluidine blue staining were used to observe the characteristics of repair tissues. Histological scores on samples in each group were measured by Wakitani score standard at different time points with light microscope. Ultramicrostructure of transplanted tissues was observed with scanning electron microscopy (SEM). RESULTS: Sixteen rabbits were included in the final analysis. Macroscopic observation: 4 weeks after the surgery, the defect was covered with tissue like cartage in the experimental group, and with periosteum in the control group. 8 weeks after the surgery, the surface of the defect was smooth, with boundary unclear in the experimental group. In the control group, the outcome was the opposite. In 12 weeks, cartilage had formed in the experimental group, and tissue like cartilage began to happen in control one. Histological observation: 4 weeks after the surgery, the defect was filled with cells and matrix with abundant proliferation of periosteal cambium layer in the experimental group, and slight proliferation in the control group. 8 weeks after the surgery, the periosteum in the experimental group became fibrocartilage with little hyaline cartilage. Just little fibrocartilage with on hyaline one was detected in the control group. In 12 weeks, the repair tissue in the experimental group approached to normal cartilage. Just fibrous tissue with little fibrocartilage was detected in the control group. Regenerative repair of cartilage defect was better in the experimental group than in the control group (P

BACKGROUND:Alogeneic bone marrow stromal stem cel transplantation for treatment of bone diseases is a hot topic. To seek effective methods for prevention of post-transplantation immune rejection is urgent to be solved.
OBJECTIVE:To explore the expression of MHC antigen on the surface of bone marrow stromal stem cels after osteogenic inductionin vitro.
METHODS:Bone marrow samples were extracted from rabbits to in vitro isolate and culture bone marrow stromal stem cels. Then, the cels were cultured in IMDM medium containing bone morphogenetic protein-2. Flow cytometry was used to analyze the expression of MHC antigen on the osteoblasts differentiated from bone marrow stromal stem cels.
RESULTS AND CONCLUSION:There was highly expressed MHC I antigen but no MHCII antigen on the osteoblasts differentiated from bone marrow stromal stem cels. After osteogenic induction, no immune rejection was found. These findings indicate that alogeneic or xenogeneic bone marrow stromal cel transplantation can be used in the treatment of bone defects.

Articular cartilage defects are common, which is one of the important factors leading to joint degeneration. Due to lack of vascular supply, the ability to regenerate itself is limited. SO the surgeons try a variety of ways to repair these defects. What specific methods are adopted should be based on the pathological types of cartilage defect in order to develop optimal strategies.

Objective To reduce the turnaround time for laboratory diagnosis of bacteremia, the feasibility of rapid identification and susceptibility testing using samples taken directly from positive blood culture bottles was evaluated. Methods The growth of microorganisms in blood culture bottles was screened by the BACTEC 9000 blood culture system. 65 positive blood culture bottles containing gram-negative bacteria were adopted to test. Culture fluid was injected into BD SST vacutainer and centrifuged to pellet blood cells. After collecting required McFarland units, they were cultured on Phoenix 100 NMIC/ID-4(identification-gram-negative bacteria and susceptibility testing) cards using 0.25 McF and 0.5 McF methods respectively. They were also evaluated by the standard method, involving subculture tests from positive blood culture bottles. Results 63 of 65 gram-negative bacteria (96. 9% ) were correctly identified with 0. 25 McF method. 59 of 65 gram-negative bacteria(90.8% ) were correctly identified with 0.5 McF method. For antimicrobial susceptibility testing, the 0.25 McF direct method had an agreement rate more than 94% , the 0.5 McF method was more than 85.7% and direct blood sample KB method was more than 93.8% compared to the standard method. But the overall minor error rate in susceptibility testing of direct blood sample KB method is higher than other methods. Conclusion Applying 0. 25 McF and 0. 5 McF rapid identification and susceptibility test was practical. During to possessing more prominent advantages, laboratory put the 0. 25 McF direct method into practice had a timely, remarkable significance.

Objective To evaluate the effects of sirolimus on scopolamine-induced cognitive dysfunction in rats.Methods Thirty male Wistar rats,aged 3 months,weighing 200-250 g,were equally randomized into 3 groups:normal saline group (NS group),scopolamine group (SC group) and scopolamine + sirolimus group (SS group).Normal saline,scopolamine 0.8 mg/kg and sirolimus 3.5 mg/kg + scopolamine 0.8 mg/kg were injected intraperitoneally in groups NS,SC and SS,respectively,and the injection was continued for 14 consecutive days.The cognitive function was assessed by Morris water maze test on 15th day.After behavior test,the rats were sacrificed and the prefrontal cortex and hippocampus were harvested for determination of amyloid β protein (Aβ) and Tau protein expression.Results Compared with NS group,the escape latency was significantly prolonged,the ratio of time spent in the target quadrant was decreased,Aβ expression in prefrontal cortex and hippocampus was upregulated and Tau protein expression in prefrontal cortex and hippocampus was down-regulated in group SC (P ＜0.05 or 0.01).Compared with SC group,the escape latency was significantly shortened,the ratio of time spent in the target quadrant was increased,Aβ expression in prefrontal cortex and hippocampus was down-regulated and Tau protein expression in prefrontal cortex and hippocampus was up-regulated in group SS (P ＜ 0.05 or 0.01).Conclusion Sirolimus can significantly improve scopolamine-induced cognitive dysfunction in rats and the changes in the expression of Aβ and Tau protein in prefrontal cortex and hippocampus may be involved in the mechanism.

Objective:To establish a method of multi-PCR to amplify the complete DNA sequence (CDS) of TCR ? and ? chain of the antigen-specific T lymphocytes in local pathologic specimen of active pulmonary tuberculosis patients, and to analyze ?/? T cell receptor gene rearrangement and CDR3 repertoire.Methods:The lymphocytes in bronchoalveolar lavage (BAL) of active pulmonary tuberculosis patients were separated. Following total RNA extraction, cDNA synthesis, Multi-PCR, recombinant clones construction, and sequencing, the CDS of TCR ? and ? chains from these lymphocytes were analyzed by using software of DNAstar and internet TCR resources.Results:24 of ? chain CDS and 13 of ? chain CDS from 3 samples of BAL were obtained. As for TCR ? chain, AV1S2 (54%), AV12S3 (41%), and AV12S2(5%) appeared frequently. BV2(38%), BV29S1(46%), BV14(3%), and BV4S2(3%) in TCR ? chain appeared more often. There were CDR3 diversities between samples and even in the same sample by amino acid sequence analysis, but there were a few identical or similar amino acid sequences. There was the same amino acid sequence of SVGTGTLHQETQY in CDR3 region of ? chain of BAL sample No.1 and No.2; The sequence of AVRDWAGNMLT appeared in two ? chains of BAL sample No.2 and No.3; Moreover, the sequence of AV…DNN…RLM appeared in ? chains of BAL sample No.2 and No.3.Conclusion:A method of Multi-PCR is used to amplify TCR ? and ? chain CDS of tuberculosis patients. There are characteristic T cell clones to proliferate,with TCR ? and ? chain repertiore skewing in local infective focus. The sequences of CDR3 in different TCR clones are mostly different but there are a few identical or similar sequences in the same patient or even between different patients. The identical amino acid sequences of CDR3 are possibly specific for recognizing MTB polypeptide.

In this paper,we report the effective killing radius and the biological killing effects of the antitank mines after bursting to cut through a base deck of the tank.The mines had different types of structure and were exploded at various angles. It was found that the fragmentation damage was the primary killing factor and a blast wave came second, accompanied by a minor thermic burn. The incidence of the blast wave was higher than the casting structure when the antitank mines with separate layer structure were exploded, as compared to those with the casting structure, but there was no significant difference in the effective killing radius.