Multi-media pedagogy is one of the widely interesting audio-visual ways in the field of education at present.This paper analyzed how to phase in this pedagogy in medical ethics course by following several aspects:The place of case pedagogy in medical ethics course, the effect of case pedagogy in medical ethics course and the practice of case pedagogy in medical ethics course.

This paper discussed the main point specifically from the three aspects which are the certainty and uncertainty of technological function , the predictability and unpredictability of technological efficiency , and“should do”or“not should do”of technological application .It presented an ethics argument of medical technology clinical admittance restriction and defends the standpoint -what we can do does not mean what we should do , aiming to provide moral theoretical support of ethical review of medical technology application .

Objective It is well known that diethylstilbestrol ( DES ) can result in testicular oxidative injury , and one of its mechanisms of action is leading to dysfunction of steroidogenesis .The aim of this study was to investigate the relationship between testicular oxidative injury caused by DES and the key synthetase activities for the synthesis pathway of steroidogenesis and the possible mechanism .Methods Twenty-four 4-wk-old male Wistar albino rats were randomly divided into 4 groups , 6 rats each.Three doses of DES (0.1, 1.0 and 10 μg/kg· d) groups and a vehicle (corn oil) control group , were respectively administered by subcutaneous injection once a day for eight weeks .The rats were sacrificed after 8 weeks treatment and the body weight , testis, epididymis, prostate were weighed, respectively.The testicular tissues were homogenized and the oxidation of MDA and ROS , the activity changes of antioxidases SOD, CAT and GPx, as well asthe activities of steroid synthetases 3β-HSD1 and 17β-HSD3 were determined by biochemical measurement.The levels oftestosterone and LH in peripheral blood were measured by radioimmunoassay .The intensities of expression of StAR,P450scc, 3β-HSD1, 17β-HSD3-mRNA were detected by PCR.Results In the 10.0 μg/kg dose group, the weights andorgan coefficients of testis and prostate were decreased significantly , the oxidation of MDA and ROS was increased distinctlyand the activities of SOD, CAT, GPx, 3β-HSD1 and 17β-HSD3 were reduced.The concentration of serum testosterone wasdecreased in the 10.0 μg/kg dose group.In the 10.0 μg/kg and 1.0 μg/kg dose groups, the decline of LH levelpresented a dose-dependent manner, and the intensities of immunochemical positive staining for StAR , P450scc, 3β-HSD1and 17β-HSD3 mRNA were decreased.Conclusions DES exposure results in disturbance of the oxidant /antioxidantbalance and decline of testosterone level that induces reproductive impairment in male rats .DES induces reductions of bothGPx and 3β-HSD activities which cause the decrease of testosterone synthesis .The expression of P450scc and 3β-HSDmRNA,which are the key synthetases in biosynthetic pathway of steroidogenesis , are inhibited by DES, and it isspeculated that the disturbance of steroidogenic synthesis enzymes may be one of the mechanisms of toxic effects of DES .

Objective:To comparatively analyze the diagnostic value of patent foramen ovale and the degree of right-to-left shunt among the traditional Valsalva maneuver (VM), the modified Valsalva maneuver (mVM) and the compression of the inferior vena cava combined with modified Valsalva maneuver (CM).Methods:A total of 132 patients with migraine, dizziness, chest pain and other symptoms in Longgang District People′s Hospital of Shenzhen from January 2021 to December 2021 were prospectively enrolled. The detection rate of patent foramen ovale and the degree of right-to-left shunt were assessed among the rest state and after performing the auxiliary maneuvers including VM, mVM and CM respectively.Results:After performing the auxiliary maneuvers, the detection rate of patent foramen ovale was significantly increased (88.6% vs 59.8%) with statistical significance (χ 2=36.026, P<0.001). There was a significant difference in the degree of right-to-left shunt among the three auxiliary maneuvers (χ 2=25.581, P<0.001). CM was the most effective for the detection of the large right-to-left shunt, and the difference was statistically significant compared with VM and mVM ( P<0.001, P=0.002). Conclusions:Auxiliary maneuvers is crucial for the diagnosis of patent foramen ovale. Compared with VM and mVM, performing CM can further improve the detection rate of patent foramen ovale and increase the degree of right-to-left shunt.

OBJECTIVETo investigate the potential effect of proteoglycan (PG) and glycosaminoglycan (GAG) on the bonding of etch and rinse adhesive to dentin, in order to improve the bonding effect of dentin.

METHODSForty-two extracted molars were used to obtain standard dentin bonding surface, and the specimens were etched for 15 s with 37% phosphoric acid and divided into three groups using a table of random numbers. Then the three groups undergone different incubating procedures as follow: specimens in chondroitinase ABC (C-ABC) group were incubated with C-ABC at 37 °C for 48 h in vibrator. Specimens in trypsin (TRY) group were incubated with trypsin, and specimens in the control group were incubated with deionized water for 48 h in the oscillators. Then specimens in each group were randomly assigned into two subgroups, A (Adper(TM) Single Bond 2) and B (Prime & Bond NT) (n = 7). The microtensile bond strength (µTBS), fracture mode and bonding interface morphology of the specimens were evaluated via microtensile testing, stereo microscope and field emission scanning electron microscopy (FE-SEM) respectively after specimens being incubated in 37 °C water for 24 h.

RESULTSThe immediate µTBS of C-ABC group bonding with adhesive A and B [(32.9±2.5) and (26.8±2.2) MPa] were significantly lower than that of the control group [(40.7±3.3) and (34.6±3.7) MPa] (P < 0.05). While the immediate µTBS of TRY group [(49.0 ± 3.6) and (44.5 ± 3.0) MPa] were significantly higher than that of the control group(P < 0.05).

CONCLUSIONSDentin PG participates in the dentin bonding process. Removal of PG increased the immediate µTBS of dentin and total etching adhesives, while removal of GAG decreased the immediate µTBS.

Acid Etching, Dental ; methods ; Bisphenol A-Glycidyl Methacrylate ; pharmacology ; Chondroitin ABC Lyase ; pharmacology ; Dental Bonding ; Dental Stress Analysis ; Dentin ; chemistry ; Dentin-Bonding Agents ; pharmacology ; Glycosaminoglycans ; pharmacology ; Hot Temperature ; Humans ; Phosphoric Acids ; Polymethacrylic Acids ; Proteoglycans ; pharmacology ; Random Allocation ; Resin Cements ; Tensile Strength ; drug effects ; Trypsin ; pharmacology