10.3969/j.issn.1007-3969.2013.05.004

Objective:To understand and compare the online learning effect of students majoring in stomatology and dental technology under the background of COVID-19 epidemic prevention and control, and to analyze the advantages and challenges of online teaching, so as to provide reference for the reform of teaching mode of stomatology education.Methods:A questionnaire survey on online learning was carried out among 267 students majoring in stomatology and 92 students majoring in dental technology in Chongqing Medical University. The results were statistically analyzed by SPSS 21.0, and chi-square test or rank sum test was used to count the data.Results:Computers and mobile phones are the main tools for students to study online. 52.92% of students used computers and 38.72% used smart phones. About 80% of the students said that they could adapt to online learning, and there was no statistical difference between the students of two majors. The online learning time of students majoring in stomatology was mainly 4-6 hours, while that of students majoring in dental technology was 2-4 hours, with statistical significance. However, the latter were more likely to ask questions to teachers than the former, and the proportion of students who often asked questions to teachers was 29.35% and 20.60%, respectively, with statistical significance. A small number of students of both majors failed log on the platform to learn and complete all the teaching materials on time. More than 50% of the students thought that online teaching was not as effective as offline teaching, and offline teaching was more conducive to mastering curriculum knowledge, without statistical differences between the students of two majors. They thought that the unsmooth learning platform, poor network conditions at home, and insufficient teaching materials prepared by teachers were the main reasons that affected the online learning effect.Conclusion:The online teaching is an important and also an advisable way to maintain teaching activities during the epidemic prevention and control of COVID-19. It will be the direction of further research on the education and teaching reform to make full use of information technology, combine the advantages of online teaching and traditional classroom teaching, and actively explore the blended teaching mode from the perspective of specialty and course characteristics.

Objective To discuss the therapeutic effect of transcatheter arterial embolization using hardening agent combined with oral propranolol in treating giant hemangioma at maxillofacial region in infants. Methods During the period from October 2013 to December 2014 at Imaging Center of Anhui Provincial Children's Hospital, transcatheter arterial embolization using hardening agent combined with oral propranolol was employed in a total of 27 infants with giant hemangioma at maxillofacial region. The age of the infants ranged from 2 months to 22 months (mean 5.9 months) and the body weight was 4.5-10 kg with a mean of 6.32 kg. Angiography via femoral artery was performed, which was followed by super-selective catheterization of hemangioma-feeding artery, and then pingyangmycin lipiodol emulsion was injected into the hemangiomas with subsequent injection of PVA particles to obstruct the hemangioma-feeding artery. After the embolization treatment, the patient received oral propranolol for 3-6 months. Results All the infant patients were followed up for 3-6 months. Clinical examination and ultrasonography indicated that the hemangioma was cured in 20 infants (75%) and the therapeutic result was effective in 7 infants (25%). Skin necrosis at hemangiomas site was observed in 2 infants (7.5%), which was cured after symptomatic treatment. No serious complications such as pulmonary embolism, cerebral embolism occurred, and no recurrence was observed. Conclusion For the treatment of giant hemangioma at maxillofacial region in infants, transcatheter arterial embolization using hardening agent combined with oral propranolol is minimally invasive, quickly effective and highly safe;and this treatment leaves no scar formation in most cases. Therefore, this technique is worthy of clinical application.

Objective To study if 5-Aza-2’-deoxycytidine along or together with 4-phenylbutyric acid could affect miR-196b expression levels in chronic myeloid leukemia cells .Methods K562 cells were treated with DNA methylation inhibitor 5-Aza-2’-deoxycytidine, histone deacetylase inhibitors 4-phenylbutyric acid separately and the combined treatment with both of them, then expression levels of miR-196b were detected using Real-time PCR.Results The half inhibition concentration of 4-phenylbutyric acid was 1.58mmol/L.Comparing with the expression level of miR-196b in normal human bone marrow cells, the expression levels of miR-196b were significantly lower in Aza group , PBA group and negative control cells and nearly consistent among three groups , and as high as normal cells in combined treatment group . Conclusion The expression level of miR-196b in K562 cells could not return to normal treated with 5-Aza-2 ’-deoxycytidine or 4-phenylbutyric acid separately , while could restore normal when treated with both agents , indicating that miR-196b expression level in K562 cells is related with both DNA methylation and histone acetylation .

Objective To study the application of Cell Counting Kit-8(CCK-8) in detecting the growth inhibiting effect of 5-Aza-2’-deoxycytidine on chronic myeloid leukemia cell .Methods The proliferation of K562 cells was detected by CCK-8 with different concentrations of 5-Aza-2 ’-deoxycytidine and the cell cycle and apoptosis of K 562 cells were detected after K562 treated by 50% inhibitory concentration of 5-Aza-2 ’-deoxycytidine .Results The 50% inhibitory concentration of 5-Aza-2’-deoxycytidine was 15.55nmol/L, after treated with this concentration , K562 cells showed that G2 phase arrest occurred , proliferation inhibited and apoptosis peaks appeared .Conclusion Inhibition of proliferation of K562 cells with different concentrations of 5-Aza-2’-deoxycytidine varied in a dose-dependent relationship , and 5-Aza-2’-deoxycytidine could promote apoptosis of K 562 cells.CCK-8 can be used in detecting the effect of 5-Aza-2’-deoxycytidine on chronic myeloid leukemia cells .

Objective To explore the cultural method of oral keratinocytes and make preparations for further investigation in using oral keratinocytes as a new choice of seed cells for the reconstruction of tissue-engineered urethra. Methods Oral keratinocytes of rabbits were isolated in vitro and seeded onto a culture dish with a feeder layer of 3T3 mouse fibroblasts inhibited by mitomycin(i3T3) or a culture dish without i3T3 respectively. Cell morphology was observed and cell growth was detected at intervals.Meanwhile,oral keratinocytes obtained from in vitro culture were performed immunofluorescence staining with broad-spectrum keratin antibody(AE1/AE3) and keratin 19 antibody(K19).The percentage of positive cells of passage 2 reactive to AE1/AE3 was assessed by flow cytometry. ResultsOral keratinocytes seeded onto a feeder layer of i3T3 exhibited finer morphous,better amplification capability,and could be passed for 7 or 8 generations.However,those cultured without i3T3 took on various morphous and could only be subcultured 2 generations before ageing.It was indicated by immunofluorescence staining that oral keratinocytes obtained from in vitro culture were positive for AE1/AE3 staining and 40% were positive for K19 staining.The result of flow cytometry revealed that the amout of positive keratinocytes reactive to AE1/AE3 was more than 95% of total cellular score. Conclusion Oral keratinocytes of rabbits can be cocultured with i3T3 in vitro and magnitude quantity can be attained,laying a favourable foundation for oral keratinocytes as a new choice of seed cells for urethral reconstruction with tissue engineering.

This paper introduces the basic principle and method of establishing a database for neuropathic images, and discusses its significance and data sharing. The database is composed of three data volumes about basic knowledge for images, cranial sectional anatomy and neuropathic images. The data sharing is achieved by using a method of linking the dynamic network of neuropathic images with database of neuropathic images. There are three searching approaches: catalog searching, key words searching and code searching.
Databases, Bibliographic ; Hospital Information Systems ; Humans ; Information Storage and Retrieval ; methods ; Neuroradiography

The fermentative H2-producing strain Clostridium sp. H-61 was isolated from anaerobic sludge,was used as an original strain which was induced by NTG and UV for increasing and the hydrogen production ability. One of the highest efficient H2-producing mutants was named as HCM-23 with its stable hydrogen production ability. which was measured in the batch culture experiments. With the condition of 10 g/L glucose,its cumulative hydrogen yield and hydrogen production rate was 3024 mL/L and 33.19 mmol H2/g DW?h,69.89% and 68.14% higher than that of the original strain,respectively. The terminal liquid product compositions showed that the mutant HCM-23 fermentation was ethanol type,while the original strain H-61 fermentation was butyric acid type. Varieties of parameters of hydrogen production fermentation studied,including time,carbon source,nitrogen source,glucose concentration,glucose utilization,initial pH and incubation temperature had been studied,indicated the optimum condition of hydrogen production for the mutantHCM-23 as initial pH 6.5,temperature 36 ℃,and the favorite substrate was sucrose. The hydrogen production characters of the mutant and the original strain were different,such as,the growth lag phase and the utilization of inorganic nitrogen source,etc. This work shows a good application potential of NTG-UV combined mutation in the biohydrogen production. And the hydrogen production mechanism and metabolic pathway should be explored furthermore.

OBJECTIVETo evaluate the feasibility and stability of chemically conjugating IgM on collagen films.

METHODSIgM was labeled with 125I using the chloramine-T method. Six collagen films were randomly divided into two groups. In chemical coupling group 125I-labeled IgM was chemically coupled with the films through N-succinmiclyl-3- (2-pyridyl-dithio) propionate reaction. In control group 125I-labeled IgM was absorbed onto collagen films. The amount of IgM on the collagen films and the amount of IgM remained on the films after extensive rinsing with phosphate buffered saline were monitored by counting the radioactivity of 125I.

RESULTSThe amount of antibodies loaded onto collagen films in the chemical coupling group was 15 times higher than that on the control films, showing significant statistical difference (P < 0.01). And the stability of conjugation antibodies on collagen films was significantly better than the control films.

CONCLUSIONChemical coupling is an effective approach to immobilize antibodies on collagen for further plasmid DNA tethering.

Angioplasty, Balloon, Coronary ; instrumentation ; Animals ; Antibodies, Antinuclear ; metabolism ; Cattle ; Coated Materials, Biocompatible ; chemistry ; metabolism ; Collagen ; chemistry ; metabolism ; Genetic Vectors ; Immunoglobulin M ; metabolism ; In Vitro Techniques ; Mice ; Protein Binding ; Stents ; Surface Properties

OBJECTIVEDiscuss the functional mechanism of treating male infertility with Bushen Shengjing pill (BS).

METHODFill the SD rat with adenine so as to injure the germ cell which will produce the model rat with kidney yang deficiency. Measure the activity of SOD and NOS, the amount of NO and MDA in the testicle.

RESULTBS can promote the activity of SOD, reduce the activity of NOS and the amount of NO and MDA.

CONCLUSIONBS has the function of protecting the germ cell which is closely related to the function that the pill can promote the activity of SOD, reduce the activity of NOS and the amount of NO and MDA.

Adenine ; Animals ; Drug Combinations ; Drugs, Chinese Herbal ; isolation & purification ; pharmacology ; Fertility Agents, Male ; pharmacology ; Kidney Diseases ; chemically induced ; metabolism ; Male ; Malondialdehyde ; metabolism ; Nitric Oxide ; metabolism ; Nitric Oxide Synthase ; metabolism ; Plants, Medicinal ; chemistry ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Spermatogenesis ; drug effects ; Superoxide Dismutase ; metabolism ; Testis ; metabolism ; Yang Deficiency ; chemically induced ; metabolism