BACKGROUND: Carbon nanotubes (CNTs) is about 1 mm in diameter and about 1-10 μm in length cylinder-like material, and it only contains the spiral of carbon atoms arranged on the surface. Because of its unique tubular structure, lower density than that of graphite and with a high enough intensity, CNTs are expected to substitute bone.OBJECTIVE: To primarily study the influence of the content of polycarbosilane (PCS) and the sintering pressure on CNTs, look for the most optimum condition for the preparation of chunk CNTs, analyze the physical properties and biocompatibility of the material, and provide a choice for candidate implant denture material.DESIGN: The content of cement and the sintering pressure are adjusted in the experiment to make sure the most optimum condition for the preparation, and the capabilities of the material are observed and analyzed to make sure if that the material is suitable for implant denture.SETTING: Department of Stomatology, Xiangya Hospital, Central South University; Prosthodontics Staff Room, Oral Medical College of Central South University. MATERIALS: 80% pure molecules of CNT (Nano Lab Company USA), 20-40 nm in diameter, 5-20 mm in length, was provided by Nacheng Technology Development Corporation of Beijing. PCS was compounded by 502 Development Room of Defense Technology University, and the molecular weight is 1 300; Ten male white Wistar rats with 8 weeks old were provided by Animal Experiment Center of Guangxi Medical University. The treatments with the animals accorded to animal ethical standard in the experiment.METHODS: The experiment was carried out in the Experimental Center of Material College, Central South University from January to August 2005. By using the spark plasma sintering (SPS), at the sintering temperature of 1 200 ℃, the pressure from 20 MPa to 60 MPa, PCS was used as the cement to produce the new chunk multi-wall CNTs.MAIN OUTCOME MEASURES: By using Archimedes method and adsorption of gases method, Japanese MitutoyoHM-101 little burden Vickers hardness meter was used to test the apparent bulk density, specific surface area, Vickers hardness at the different contents of PCS and sintering pressures. Scanning electron microscope (SEM) and transmission electron microscope (TEM) were used to observe the microstructure of the material.RESULTS: ① Microstructure: SEM and TEM indicated that the nanotube structure of the material was retained after sintered. ② Conforming phase of material: X-ray diffractometer indicated that carbon nanotubes were felt by PCS pyrolysis product of SiC; along with the PCS content and sintering pressure increased, the specific surface area was reduced, and Vickers hardness and density increased. Specific surface area decreased. ③ Histological compatibility: The inflammatory reactions of the CNTs/PCS were little more serious along with the increase of the content of PCS. The physical property of carbon nanotubes was prepared in this way, it was closed to bone tissues, it had the better biocompatibility, and it was the suitable candidate implant denture material.CONCLUSION: Appropriate to PCS for the bonding agent, through SPS, at 1 200 ℃, 20-60 MPa sintering pressure, CNTs/PCS which the material property is closed to bone tissues can be prepared, and CNTs/PCS subcutaneous implantation in rats does not show significant rejection; therefore, it is suitable candidate for dental implants material.

BACKGROUND: Titanium cage of cervical vertebral fusion is often used during a surgical operation for cervical syndrome; however, it has a bad impact on the operative effect because of submerging.OBJECTIVE: To observe the biocompatibility and stability of cervical fusion cage of high molecular polyethylene in animals.DESIGN: A randomized grouping and observational control experiment.SETTING: The Animal Experimental Center of Zhengzhou University.MATERIALS: Twenty female goats without pregnancy at 1.1-1.6 years of age.METHODS: The experiment was conducted at the Animal Experimental Center of Zhengzhou University between June and November 2001. Twenty goats were equally randomized into experimental group and control group.Self-made cervical fusion cage filled with autogenous spongy bone was implanted into the goats in the experimental group, only autogenous iliac bone was implanted in the control group. X-ray for observing the changes in the height of intervertebral space was performed in two groups 6 weeks later. All the animals were killed under anesthesia to extract cervical vertebra samples, which were placed on YJ-14 Biomechanical Tester to measure anti-compression ability and height of intervertebral space and to observe pathological changes.space: Compression loading in the experimental group was significantly higher than that in the control group [(358.64±15.63),(268.82±11.36)N,P ＜ 0.05]; however, there was no difference in the height of interverteA great amount of osteoblasts were found in the tissues around the cage in the experimental group, but there was no difference between the two groups.CONCLUSION: The self-designed cervical vertebral fusion cage possesses high upholding strength, good biocompatibility and stability and can play a role in stabilizing the height of intervertebral space.

95%) was performed in 62 cases, a subtotal resection (76%~95%) was performed in 6 cases, and a partial resection (≤75%), 2 cases. No peri-operative deaths occurred. Transient diabetes insipidus was noted in 24 cases and was cured within 3 weeks after operation. Nasal cerebrospinal fluid leakage was observed in 8 cases, 5 of which spontaneously recovered after 2 weeks of bed rest, and 3 of which were cured by lumbar cistern drainage. Follow-up observations for 3 months ~ 2 years (mean, 7 months) in 48 cases found 2 cases of recurrence. Conclusions Transnasal transseptal transsphenoidal approach adenomectomy is an effective and minimally invasive procedure, with simplicity to performance, short operative time and fewer complications.

Objective To investigate the changes of the serum high sensitive C-reactive protein (hs-CRP)level in patients with acute cerebral infarction (ACI) and study the relationship between hs-CRP level and ischemic stroke subtypes according to the trail of org10172 in acute stroke treatment (TOAST) criteria.Methods The serum hs-CRP was measured in 152 ACI patients by immunonephelometrical method. All ACI patients were classified into 5 major ischemic stroke subtypes based on TOAST criteria. And then the relationship between hs-CRP level and their TOAST subtypes were analysed.Results The percentage of each ischemic stroke TOAST subtypes of 152 patients was as following: stroke of undetermined etiology 41.45%, small-vessel occlusion 34.87%, cardioembolism 5.26%, large-artery atherosclerosis 15.79%, and stroke of other determined etiology 2.6%. Among 5 ischemic stroke subtypes, cardioembolism patients were related to the highest positive rate of hs-CRP(87.50%) and the highest hs-CRP level [(11.60?7.85)mg/L]. The hs-CRP level in large-artery atherosclerosis or stroke of other determined etiology were (10.77?4.27) mg/L or (6.45?3.25) mg/L respectively, Stroke of undetermined etiology and small-vessel occlusion subtypes were associated with the lowest positive rate of hs-CRP(38.10%, 37.74%) and the lowest hs-CRP level [(4.09?5.65)mg/L,(3.99?0.56)mg/L]. Apparently, other factors, such as age, systolic blood pressure, cholesterol, triglyeride, fasting blood sugar and fibrinogen, could also affect the hs-CRP level in serum(r=0.1640、0.2489、0.2066、0.1866、0.3029、0.2224,all P

0.05). But there were statistic difference in the those indexes and pathological changes of bile duct and liver between A and ligation groups on the 30th and 90th day after operation (P

Objective To study the correlation of NF-?B expression with the grade, the stage, the recurrence, the metastasis and PKC expression of bladder transitional cell carcinoma. Methods The expression of NF-?B and PKC was examined with SP immunohistochemical method in 54 cases of paraffin-embedded bladder transitional cell carcinomas tissues and 13 cases of normal bladder tissues. Results The positive expression rate of NF-?B P65 and PKC in bladder transitional cell carcinomas was 88 9% and 81 5% respectively. The expression rate of NF-?B decreased along with pathological grade and clinical stage increased, while its expression increased along with the rate of recurrence and metastasis elevated. There was a positive relationship between NF-?B and PKC expressions. Conclussion NF-?B may play a role at early stage of bladder transitional cell carcinoma. It probably serves as an index to evaluate the malignant extent and progression of bladder transitional cell carcinoma. PKC probably takes part in the activation process of NF-?B.

BACKGROUND: The vibration of high speed handpiece during tooth preparation may have adverse effect on the continuous force of the bonding interfaces among the cement, dentin, and post core. OBJECTIVE: To find the effect of different types of cements on the coronal microleakage of fiber post under different tooth preparation timings, and to provide evidence for the clinical operation. METHODS: The extracted mandibular premolars were divided into 3 groups, and they were cemented by Rely X luting, Panavia F and Paracora 5 mL, respectively. Each group was averagely divided into 3 subgroups: A, B, C groups which were prepared 15 minutes, 45 minutes, and 90 minutes after the cements mixed. All roots were then dyed and transparented. The teeth were observed under stereoscopic microscope and the dyeing scores were also recorded. RESULTS AND CONCLUSION: Rely X luting caused the highest coronal microleakage of fiber post, followed by Panavia F, while Paracore 5 mL, brought about the lowest under the same tooth preparation timing. Different tooth preparation timing caused no significant effect on the coronal microleakage of fiber post when the cement had been completely set.

Objective: To investigate the influence of electroacupuncture (EA) combined with repetitive transeranial magnetic stimulation(rTMS) on the temporal profile of nestin expression after induction of focal cerebral isehemia in adult rats and to explore the mechanism of EA combined with rTMS in treating ischemic brain injury. Method: The model of transient focal ischemia was produced by occlusion of middle cerebral artery. Seventy-five Wistar rats were randomly divided into normal group, model group, EA group, rTMS group and EA +rTMS group. The neurologic impairment rating and ability of learning and memory were observed at the 7th、14th and 28th d after infarction respectively. Meanwhile, Western blotting was used to observe the number of nestin expression positive cells. Result: Nestin-positive cells were found in cortex, subgranular zone (SGZ), subventricular zone (SVZ) of the ipsilateral side at different time points after cerebral isehemia. The number of nestin-positive cells peaked at the 7th d, began to decrease at the 14th d and was significantly higher in EA+rTMS group than that in model group (P<0.05), then almost reached normal at the 28th d. The improvement of neural motor function deficits as well as the indexes of learning and memory were more obvious in EA+rTMS group compared with model group (P<0.01, P<0.05). These effects were most obvious in EA+rTMS group compared with the EA and rTMS group (P<0.05). Conclusion: EA and rTMS possess the potency of building up and can increase the number of nestin-positive cells in some brain regions after focal cerebral ischemia, which might be one of the important mechanisms of EA combined with rTMS in treating ischemia brain injury.

Objective To investigate the association between CYP2C19 polymorphisms and efficacy of clopidogrel in Chinese Han patients with coronary atherosclerotic heart disease.Methods A total of 176 Chinese Han patients who underwent percutaneous coronary intervention and were treated with dual antiplatelet therapy with aspirin and clopidogrel were enrolled.Polymorphisms of CYP2C19 * 2,* 3 were measured by PCR-restriction fragment length polymorphism (PCR RFLP).The correlation between the genetic variants and cardiovascular events was analyzed.Results In the 176 patients,the allele frequencies of CYP2C19 * 2 and * 3 were 34.38％ and 5.97％ respectively,the percent of patients with poor metabolizer genotypes (* 2/* 2,* 2/* 3,* 3/* 3) was 14.20％.Among the 176 patients,11 patients reoccured acute coronary syndrome,1 patient suffered from stroke,and 4 patients had stent thrombosis.The incidence of cardiovascular events was 9.09 ％.Thecumulative incidence of cardiovascular events had no significant differences between poor metabolizer genotype carriers and extensive and intermediate metabolizer genotype carriers (16.00％ vs.7.95％,x2 =1.683,P=0.195).Conclusions The frequencies of CYP2C19 poor metabolizer genotypes are higher in Chinese Han population than in Caucasians,but the incidence of cardiovascular events in Chinese Han population is not increased.

Objective To investigate the pattern of fluctuations and clinical significance of fasting serum insulin(FINS) and C-peptide(CP) levels in patients with different subtypes of acute cerebral infarct(ACI) and its relationship with serum lipid. Methods FINS and CP were measured in 152 ACI patients by chemiluminescent immunoassay. All ACI patients were classified into 5 major ischemic stroke subtypes according to the trial of org10172 in acute stroke treatment(TOAST) criteria. And then the relationship between FINS and CP level and serum lipid in different TOAST subtypes were analysed. Results The percentage of each ischemic stroke TOAST subtype was as follow: stroke of undetermined etiology 40.13%, small-vessel occlusion 34.21%, cardioembolism 5.26%, large-artery atherosclerosis 15.79%, and stroke of other determined etiology 4.61%. Among 5 major stroke subtypes, large-artery atherosclerosis patients had the highest levels of FINS and CP. The levels of FINS and CP in small-vessel occlusion were (8.237?5.144) ?U/ml and (1.761?0.975)ng/ml,respectively. Stroke of other determined etiology subtypes were associated with the lowest levels of FINS and CP. Apparently, other factors, such as TC, TG, LDL, SBP, DBP, age and HDL, could also affect the levels of FINS and CP in serum. Conlusions Levels of FINS and CP varied in different subtypes of ACI. There was a significant correlation among insulin resistance, hyperinsulinemia(HIS) and lipid metabolic abnormality in ACI.