Objective: Our aim was to evaluate the biocompability of porcelain compounded with nanostructured material. Methods：The proliferation of the NIH3T3 cells were investigated using a tetrazolium-based colorimetric assay(MTT assay).Maceration extract of four tested materials were added into culture plate .The samples were tested with ultraviolet spectrophotometer in 490 wavelength at 1，3，5，7 days after the addition of extract. Morphology of these cells was also observed with phase-contrast microscope. Results： There was no obvious difference among three kinds of prosthetic materials in the optical absorbance and the cells growing in the extract showed normal morphology. Conclusion: The toxicity graduation of the porcelain compounded with nanostructured material is 0. This material has a good biocompability and can be used clinically.

A method which combines empirical mode decomposition with wavelet transform is employed to remove breathing baseline draft from pulse wave signal. First of all, this method decomposes pulse wave signal into several intrinsic mode functions and judges the intrinsic mode function which contains the information of breathing baseline draft. And then wavelet transform is used to decompose these intrinsic mode functions, and the detail coefficients representing breathing baseline draft are set into zero. At last, the signal is rebuilt. This can realize removing breathing baseline draft. A self-developed measurement device was used to obtain the pulse wave signal for validating, and AC-DC modulation ratio value was adopted to evaluate the effect. The results showed that this method could effectively remove breathing baseline draft from pulse wave signal.
Algorithms ; Oximetry ; instrumentation ; methods ; Respiration

Objective To identify risk factors for anastomotic leakage after low anterior resection (LAR) in rectal cancer patients and study its impact on patients'long-term prognosis.Methods Chnical data were analyzed from 720 patients who underwent low anterior resection(LAR) for rectal cancer between 1996 and 2006.Results Anastomotic leakage after anterior resection occurred in 44 cases(6.1%).The median time of anastomotic leakage after operation was 5.6 days.Muhivariate analysis showed male patients.history of preoperative chemoradiation therapy,diabetes,cancer distance from anus less than 7 cm and hand-sewed anastomosis were independent risk factors predisposing anastomosis leakage (P<0.05).Tumor local recurrence rate was 13.6% in patients suffering from leakage and 5.9% for those without leakage (χ2= 4.116,P<0.05).The distant metastasis rates were 25.0 and 14.1 percent for the leakage and noaleakage groups,respectively(χ2=3.943,P<0.05).The survival rates were 56.8 and 72.5 percent in the leakage and nonleakage groups,respectively(χ2=4.979,P<0.05).Conclusion Sex,preoperative chemoradiation therapy,diabetes,cancer distance from anus less than 7 cm and hand-sewed anastomosis were found to be independent risk factors for anastomotic leakage after rectal cancer surgery.Anastomotic leakage was associated with poor prognosis.

OBJECTIVEThis study aims to do the following: construct a three-dimensional finite element model of an labial inverted impacted maxillary central incisor and its supporting tissues, analyze stress distribution in the periodontal tissue when various tractions are exerted, and provide references for treating impacted maxillary central incisor.

METHODSA three-dimensional finite element model oflabial inverted impacted maxillary central incisor and its periodontal tissues was established using Mimics 10.01 and Ansys 14.0 software based on original cone beam computed tomography (CBCT) data. Various traction values (20, 30, 40, 50, 60, and 70 g) were exerted on the incisal margin in the direction perpendicular to the impacted tooth. Different Von Mises stress values were determined.

RESULTSStress distribution on the periodontal ligament increased with traction size. When 30 g traction was exerted on the labial inverted impacted maxillary central incisor, the Von Mises stress was 24 919.0 Pa, which was within the range of the optimum force and close to its maximum value.

CONCLUSIONThe optimum traction for early orthodontic treatment of labial inverted impacted maxillary central incisor is nearly 30 g.

Objective To investigate the biological characteristics of recombinant hIFN-α-2B-BCG and its direct effect to bladder tumor cells in vitro. Methods BCG and recombinant BCG(rBCG) wild-type growth and morphology were compared. After 10 generations, hIFN-α-2B content was analyzed by ELISA, of bacteria in vivo and in vitro. The effects of rBCG on bladder cancer cells EJ, MB49, were detected by elec-tron microscopy and cell inhibitory rate from MTT. Results The normal BCG and rBCG had no significant difference in growth phase. They were both positive for acid-fast stain, maintaining the characteristics of cell's connection. While rBCG slightly larger than normal BCG, no else abnormality was obvious between them. IFN-α-2B was 997.2 pg/ml in secretions, 99.3 pg. In bacteria in vivo, 990.3 pg/ml in 10th genera-tion's sections, of rBCG. Compared with 1st generation, rBCG had no significant differences in morphology and interferon expression. Normal BCG and rBCG both had, anti-proliferation directly on bladder tumor cell in vitro, the rBCG is most effective in all. After rBCG cultivated with bladder tumor cell together, tumor cell's slow proliferation, detach, quantity decreasing and death were observed under microscope. Different degeneration in degree on most of tumor cells, disorganization on organelle, aggregation on chromatin, pyc-nosis on nucleolus, and cytoplasm lysis were on tumor cell under transmission electro microscopy. MTT as-say showed rBCG inhibited the proliferation of bladder caner cell and more active than normal BCG. Conclu-sion These results suggest that the rBCG have the same characteristics in growth phase as normal BCG, and stable properties in interferon expression and morphology by generations, rBCG has more anti-tumor effects in vitro than normal BCG.

Objective To define the indications and evaluate the results of various surgical treatment options in patients with nonparasitic hepatic cysts. Methods The clinical data of 284 patients with nonparasitic hepatic cysts treated in our hospital from January 1995 to December 2005 were retrospectively analyzed. Results Percutaneous aspiration and sclerotherapy were performed in 161 cases and complications occurred in 9 (5.59%), recurrence in 53 (32.92%) and the mortality was 0%.Open surgery was conducted in 71 cases and the complications occurred in 16 (22.54%), recurrence in 8 cases (11.27%) and the mortality was 2.82%. Laparoscopic surgery was employed in 52 cases and complications occurred in 7 ( 13.46%), recurrence in 6 (11.54%) and the mortality was 1.92%.Conclusion There is currently no general agreement in the literature concerning when nonparasitic hepatic cysts should be treated. Laparoscopic surgery was more favorable than other therapeutic options.However, we should choose individually suitable methods according to different clinical symptom of patients.

Objective To evaluate the safety of central lymph node dissection with total thyroidectomy for papillary thyroid carcinoma. Methods A meta-analysis on the data of suitable seven clinical researches was performed using the Mantel-Haenszel method and the risk difference was calculated.Results Seven studies with a total of 1524 patients were eligible for inclusion, 620 were with totalthyroidectomy plus central lymph node dissection and 904 with thyroidectomy alone. There was a significant increased risk of temporary hypocalcaemia ( P = 0. 03 ) and temporary vocal cord palsy ( P = 0. 01 ) when central lymph node dissection was performed in addition to a thyroidectomy. However, the risk of permanent hypocalcaemia( P = 0. 32 ) and permanent vocal cord palsy (P = 0. 75 ) has no statistical difference between the two groups. Conclusion Central neck dissection added to thyroidectomy does not increase rate of permanent morbidity in thyroid cancer patients.

Objective To study the complex restitution relation between the present action potential duration (APD) and its previous diastole interval (DI) and APD. Method The Luo-Rudy model was paced with different protocols to draw the coordinate curves between the present APD and its first previous DI. These curves were fit with the artificial neural network (ANN). Result Different pacing protocols caused different coordinate curves, and there was no one-to-one relation between pre-sent APD and its first previous DI. ANN fits these curves satisfactorily. Conclusion There is a complex relation between the present APD and the APDs and Dis of the first three previous beats. This relation can be modeled accurately with ANN.

In order to overcome the effects of the anti-aliasing filter and the colored background noise, an adaptive algorithm is proposed to estimate the parameters of ion channel kinetics and the background noise, and whereafter the ion channel signal could be restored from the strong noisy patch-clamp recordings. The algorithm cross-couples the recursive expectation-maximization algorithm, which estimates optimally the parameters of hidden Markov model, and the recursive extended least square algorithm, which estimates optimally the characteristics of the background noise. Simulation suggests that this cross-coupling algorithm convergences consistently, and is very robust to the inexact conformation number.
Algorithms ; Ion Channels ; physiology ; Least-Squares Analysis ; Likelihood Functions ; Models, Theoretical ; Noise ; Patch-Clamp Techniques ; methods ; Signal Processing, Computer-Assisted

One third of estrogens in the male are from the testis and the others from outside the testis. Aromatase P450 (CYP19) is an enzyme responsible for the conversion of androgens to estrogens. Estrogens regulate cell function via specific receptors--estrogen receptors (ER) which include ER alpha and ER beta. It has been found that the role of estrogens in male reproduction is complex and important, particularly during the neonatal life. Males lacking ER alpha are completely infertile because ER alpha-induced estrogens regulate the reabsorption of luminal fluid in the head of the epididymis and disruption of this essential function causes sperm to enter the epididymis diluted, rather than concentrated, resulting in infertility. Whereas males lacking aromatase or ER beta are fully fertile. Therefore, it is concluded that ER alpha, but not aromatase or ER beta, is essenitial for normal male fertility.
Animals ; Aromatase ; physiology ; Estrogen Receptor alpha ; Estrogen Receptor beta ; Estrogens ; physiology ; Humans ; Male ; Receptors, Estrogen ; physiology ; Reproduction ; physiology