BACKGROUND:Studies have confirmed that the surface treatment methods such as silane coupling agent and sand blasting could improve bonding strength of zirconia ceramics and resin binder. In addition, the increase of micro cracks on the surface of zirconia ceramics can also improve the bonding strength of zirconia ceramics and resin binder. But there is a lack of related studies addressing whether repeatedly sintering would have an impact on shear bond strength of zirconia ceramics.
OBJECTIVE:To determine the effect of decorative porcelain temperature firing on the shear bond strength between dental zirconia ceramics and resin binder.
METHODS:Twenty pieces of zirconia ceramics specimens were selected from 40 tablets, and then randomly divided into five groups according to the number of sintered times:control group (without sintering), sintering groups for 2, 4, 6, 8 times. Heat starting temperature was 500 ℃, and final temperature was 1 000 ℃ with a heating rate of 55 ℃/min. The vacuum time was 7 minutes. During the sintering, the final temperature was constant. Unsintered ceramic pieces were bonded using resin binder. Universal testing machine was used to test the shear strength of the interface between the two pieces of zirconia ceramics. The interface after shearing was characterized by scanning electron microscope.
RESULTS AND CONCLUSION:The shear strength of sintering groups for 4, 6, 8 times was significantly higher than that of the control group (P<0.05). Shear strength of specimens sintered twice was slightly higher than that of specimens without sintering, but the difference was not significant (P>0.05). Shear strength of specimens sintered 8 times was slightly higher than that sintered 4 and 6 times (P<0.05). Under the scanning electron microscope, there was no crack on the surface of non-sintered zirconia ceramics. After 2 times sintering, the surface appeared to have fine cracks. After sintering 4 times, visible cracks were increased. After six rounds of sintering, the surface began to have significant changes;cracks rose along with slight gaps and a smal amount of adhesive residues were found. After sintering for 8 times, cracks and voids were obviously increased on the sintered surface and adhesive residues were found. It indicated that after sintering for 4, 6 and 8 times, zirconia ceramics could have a good shear strength binding to resin adhesives;with the increasing of sintering times, the shear bond strength could be increased.

Objective To investigate the factors that induce constipation in bedridden patients undergoing replantation of severed finger and find countermeasures. Methods A retrospective investigation was carried out in 92 patients undergoing replantation of severed finger, their constipation and factors influencing constipation were recorded. Results 61 patients suffered from constipation in total 92 cases,the rate being 66.30%. 76 patients reduced food intake, and 59 cases presented constipation (the rate being 77.63%). Factors influencing constipation included being unaccustomed to defecate in bed (the rate that present with constipation being 87.09%),reluctant to trouble others(75.47%), side effects of drugs(55.56%) and lack of dietary knowledge (71.87%), decreasing food intake was closely bound up with constipation. Conclusions Proper psychological counseling, strengthening of health propaganda, comfortable facility for defecation, improved family support and oral food intake can significantly reduce the proportion of constipation and increase comfort degree of patients.

Objective To investigate the prevalence, clinical features, diagnosis, treatment and the influence on procreation of uterine malformation. Methods Totally 225 women with uterine malformation referred to our hospital from Mar 1990 to Jan 2005 were involved in this retrospective analysis.The constituent ratio, clinical feature, diagnosis, treatment and the influence on procreation were analyzed.Results (1) Among 225 cases of uterine malformation, 125 cases (55.6%) were septate uterus; 122(97.6%, 122/125 ) of these patients became pregnant, but always associated with a high risk of reproductive failure and obstetrical complications, such as abortion, abnormal fetal presentation, premature rupture of membrane. (2) Among 51 cases (22. 2%, 51/225 ) of didelphia, 50 cases (98%, 50/51 )became pregnant without any influence from this malformation. Five cases were combined with urinary system complication. (3) Among 26 cases (9.7%, 26/225 ) of rudimentary horn of uterus, 4 cases (15%, 4/26)became pregnant, and 1 case (4%, 1/26) presented with ipsilateral oviduct ectopic pregnancy; 2 cases (8%, 2/26) were combined with urinary deformities. (4) In 14 cases (6. 2%, 14/225) of bicornuate uterus, 1 case (7%, 1/14) presented with urinary tract abnormalities; gestations were more common, but due to the uterine structural abnormality, recurrent miscarriage and premature delivery were unavoidable.(5) Others: none came up with sterility in 4 cases (1. 8%, 4/225) of saddle shaped uterus. All the three cases ( 1.3% , 3/225) of ametria were with the chief complaint of primary amenorrhea. Two cases of unicornis uterus (0.9%, 2/225) were both complicated with sterility, while neither with urinary system deformities. Conclusions Among uterine malformations, septate uterine is the most common type. Septate uterus, didelphic uterus, bicornuate and rudimentary horn of uterus do not affect pregnancy, but can cause different complications. Unicornis uterus always causes sterility. Uterus malformations often come up with urinary system deformities.

Objective To explore the electrophysiological properties and the disparity of visual cortical neurons in developing rats. Methods Whole cell patch clamp recording and intracellular labeling of brain slices were performed on rats at postnatal 14 and 28 days. The electrophysiological data were analyzed according to the cellular input resistance and resting membrane potential. Results When the input impedance of visual cortical neurons(IR) was lower, increased peak value of postsynaptic currents(PSCs), prolonged rise and decay time were found. At postnatal 14th day(before eyes opened), the intermediate cells and mature cells were 59.2% and 14.9% respectively, but at postnatal 28th day(14 days after eyes opened), the mature cells and immature cells were 62.5% and 12.5% respectively. Conclusion During the period of postnatal development, the visual cortical neurons become mature gradually, but maturation is not completely correlated with age.

Objective To investigate the effect of diuretics combined with the new class volume-removing drugs nesiritide and tolvaptan on refractory heart failure (RHF).Methods We collected 78 patients with RHF from cardiovascular ICU in our hos-pital,and patients were divided into combined volume-removing drugs treatment group (CVR group)and traditional diuretics com-bined with inotropic treatment group (control group).We observed the differences in the heart failure symptoms control rate and the average hospitalization days between the two groups.The difference in average urine volume and weight loss during hospitaliza-tion was observed.Results The heart failure symptoms were controlled and successful discharge in 89.7% of patients in CVR group,which was better than that in control group(71.8%).The corresponding rates of death or abandonment was decreased sig-nificantly in CVR group,and the average number of hospitalization days in CVR group was significantly shorter than that in control group(P <0.05).Meanwhile,the average daily urine volume and the weight loss decreased significantly in CVR group than those in control group(P <0.05).Conclusion The therapy strategy of combined volume-removing drugs can significantly improve the vol-ume removing and control rate of heart failure symptoms.

AIM To investigate the effects of Tongluo Xingnao Effervescent Tablets (Chuanxiong Rhizoma,Angelicae sinensis Radix and Scutellariae Radix) on the learning and memory function in SAMP8 mice,and improvements in cognitive function.METHODS Morris water maze was used to evaluate the change of cognitive function in SAMP8 mice after they were treated with Tongluo Xingnao Effervescent Tablets for 60 d,and the activity of superoxide dismutase (SOD),the concentration of protein carbonyls (PC),the ratio of NAD +/NADH in brain tissue were detected by ELISA,the expression of Nampt,SIRT1 and FOXO3 in hippocampus were measured with immunohistochemical methods.RESULTS Tongluo Xingnao Effervescent Tablets shortened escape latency and obviously increased percentage of time in target quadrant in hidden platform test and increased the times entering the target quadrant in spatial probe test in SAMP8 mice.It evidently enhanced the activity of SOD,the ratio of NAD +/NADH and distinctly decreased the protein carbonyls level.Moreover,Tongluo Xingnao Effervescent Tablets could markedly up-regulate the expression of Nampt and SIRT1,but evidently down-regulate FOXO3 protein expression.CONCLUSION The experimental data show that Tongluo Xingnao Effervescent Tablets can enhance the cognitive function of SAMP8 through regulating Nampt/SIRT1/FOXO3 signal pathway.

Objective To analyze the epidemiological status and risk factors of urinary calculus in residents of zhuo-zhou city. Methods A total of 19 446 residents in zhuozhou city were surveyed with a stratified random sampling method. The questionnaire included body mass index (BMI), daily water consumption, sweets, meals taste, cooking oil, high-protein diet and family history. A 1∶1 ratio was used to select the matched normal control group. Logistic regression analysis was used to compare BMI, diet habits, family history of renal stones and other risk factors of urinary calculus between two groups. Results There were 1 752 (9.8%) patients were confirmed as urinary calculus in 17 854 follow-up members, in which there were 1 125 male and 627 female. A total of 843 patients were at 0-40 years of age (48.04%). The incidence of urinary calculus was mainly in the second and third quarter of the year, and mainly was ureteral stones. There were significant differ-ences in BMI, daily water consumption, sweets, meals taste, cooking oil, high-protein diet and family history between two groups. Logistic regression analysis showed that the protective factors included more daily water consumption, lower level of BMI and eating vegetable oil. And the risk factors of urinary calculus were salty taste, sweet taste, high protein diet and fami-ly history of urinary calculus. Conclusion Prevention measures of urinary calculus included controlling body mass, drink-ing more water, and controlling high-protein, high-sugar, high-salt food intake.

Objective To study the effect of simvastatin (SIM) on the expression of neuron specific enoalse (NSE) in rat brain and serum after traumatic brain injury (TBI), and therapeutic effects of SIM on TBI thereof. Methods A total of 90 Sprague-Dwalye (SD) rats aged 8 weeks were randomly divided into sham TBI group, control group and treatment group (n=30). The TBI model was established in control group and treatment group by using Feeney method. Rats in treatment group were fed SIM 10 mg/kg in the evening pre-injury and in every evening post-injury while those in control group were fed the same dose of starch at the same time. Blood samples (3 mL) were collected from carotid atrery in three groups, then rats were sacrificed and brains were collected at different time points (3 h, 12 h, 24 h, 3 d, 7 d and 14 d post-injury). The serum ex-pressions of NSE were detected by ELISA method. The NSE expressions in hippocampal area CA3 were detected with immu-nohistochemistry. Results (1) In control group, the serum NSE level was significantly increased at 3 h after injury, reached the peak at 3 d, and was still higher than that of sham injury group at 14 d. In treatment group, the serum NSE level was in-creased 3 h after injury, reached the peak at 24 h, decreased after 3 d, and was near the sham injury group at 14 d after inju-ry, but was significantly lower than that of control group. (2) Immunohistochemical detection showed that the NSE optical density values in hippocampal area CA3 area were decreased at 3 h after injury in control group. The optical density values reached the lowest level between 3 d to 7 d and were still significantly lower than those of sham injury group at 14 d. In treat-ment group the optical density value was decreased at 3 h after injury, reached the lowest level between 12 h to 24 h and re-bounded significantly at 7 d, then at 14 d up to the level of sham injury group. Conclusion SIM can promote the decrease of serum NSE level in TBI rats and increase the NSE expression of hippocampal neurons of injured side, showing protective effects on neuronal damage after traumatic brain injury.

Eight patients with suspected cases of C .jejuni were etiologically diagnosed and analyzed in this study to pro-vide scientific basis for the confirmation of the cases of human campylobacteriosis in Guizhou Province ,China .Blood or feces of 8 suspected patients were employed to isolate bacteria strains .Conventional and multi-PCR techniques were applied to identify suspicious bacteria strains .The C .jejuni strains were analyzed by using Pulsed Field Gel Electrophoresis (PFGE) .Suspicious strains of C .jejuni were isolated from all the 8 suspected patients of campylobacteriosis and anticipated genes fragment were detected with multi-PCR .With the digestion of restriction enzyme SmaI ,the 8 C .jejuni strains were divided into 7 PFGE pat-terns with 7-10 DNA bands .Cluster analysis showed that the gross similarity of 8 strains of C . jejuni was more than 50% . The similarity of PFGE patterns between strain GZ201004 and GZ201005 from diarrhea patients was as high as 100% ,while the similarity of strain GZ201201 and GZ201007 was 66 .7% .Moreover ,C . jejuni were detected from all the suspected pa-tients of campylobacteriosis .PFGE results indicated that strains GZ201004 and GZ201005 were from the same source ,while all the 8 isolates showed PFGE polymorphism .

Objective To assess the variations in different thyroid stimulating hormone(TSH) and free thyroxine (FT4) detection kits for evaluating thyroid function during pregnancy and to establish the corresponding normal reference ranges.Methods This study was based at the International Peace Maternity and Child Health Hospital affiliated to Shanghai Jiaotong University School of Medicine.A total of 200 pregnant women who visited the hospital between June,2011 and September,2012 were recruited in this study according to the National Academy of Clinical Biochemistry (NACB) criteria.Blood samples were sequentially collected from the women at the first (T1,9-12 weeks),second (T2,16-24 weeks) and third (T3,32-36 weeks) trimesters to determine the serum TSH and FT4 levels using four different detection kits (Siemens-C,Siemens-Ⅰ,Abott and Roche).A linear trend test was used to analyze serum TSH and FT4 levels with four different kits.A percentile range of P2.5 to P97.5 was used to establish the normal trimester-dependent reference ranges of TSH and FT4 levels for different detection kits.The Bootstrap method was used to compare the differences in the four reference ranges.Results Similar dynamic changes in TSH and FT4 levels during pregnancy were detected among the different kits (F=0.950,P=0.595; F=11.640,P=0.081,respectively).Among the four reference ranges of TSH,the Roche kit showed the most remarkable fluctuation during pregnancy,while Roche kit in the first trimester and Siemens C kit in the second and third trimesters showed larger fluctuations in reference ranges of FT4.More importantly,the reference ranges of TSH and FT4 showed significant variations among the four different kits in each trimester (TSH:T1:F=2 945.390,P ＜ 0.01; T2:F=2 826.260,P ＜ 0.01; T3:F=1 698.360,P ＜ 0.01.FT4:Tl:F=1 145.440,P ＜ 0.01; T2:F=2 260.240,P ＜ 0.01; T3:F=1 439.920,P ＜ 0.01).Conclusions TSH and FT4 measurement using four different commercial kits showed similar trimester-dependent dynamic changes.However,it is necessary to establish trimester-dependent and detection kit dependent normal reference ranges of TSH and FT4 for thyroid function evaluation for pregnant women.