Consumer Product Safety ; legislation & jurisprudence ; Legislation, Food ; Toxicology

Objective Medical statistics is an important tool in scientific research and practice.The article was to evaluate the current knowledge, learning needs and related influencing factors of medical statistics among medical doctoral students to provide references for the optimization in the teaching mode of medical statistics. Methods A questionnaire was used to investigate Grade 2014 doctoral students who took medical statistics course before and after the teaching in a medical university. Results The knowl-edge of doctoral students were at different levels and they had different learning requirements.More than 81.4% of the respondents have difficulty in the choice of scientific and reasonable design and the scientific design.Over 50%students had insufficient knowledge of advanced statistics and poor software application ability.They had the demands for more practical cases explanation in theory course, more software teaching hours and some short term specialized courses. Conclusion The university and teachers should carry out teaching reform according to the particularity of doctoral students and teach in small sections according to their knowledge levels of sta-tistics and learning requirements.It is suggested that the teaching should be combined with the students'own research projects in order to improve the teaching effect and improve the students'ability in sta-tistical design and solving the practical problem in scientific research statistics.

Background Researches showed that thymic stromal lymphopoietin (TSLP) is an interleukin-17-like inflammatory factor and plays important roles in the pathogenesis and development of allergic diseases.However,the study whether TSLP plays roles in allergic conjunctivitis is rare.Objective This study was to investigate the expression change of TSLP and IL-4 in ocular surface tissue and cervical lymph node in the mice with allergic conjunctivitis induced by artemisia annua,a common plant in China,and to explore the role of TSLP and IL-4 in the pathogenesis and development of allergic conjunctivitis.Methods Twenty female BALB/c mice aged 6-8 weeks were randomized into normal control group and model group.Antigen solution was prepared using 400 μl extracting solution of artemisia annua pollen with 400 μl antigen solvent.The mouse models of allergic conjunctivitis were established by injection of 50 μl antigen solution in footpad followed by ocular topical administration of extracting solution once a day from day 10 to 12 after injection,and no any intervention was given in the normal control group.The mice were sacrificed and eyeballs were obtained 13 days after modeling,and corneal epithelium,conjunctiva and cervical lymph nodes were harvested for the detection of TSLP mRNA and IL-4 mRNA by real-time PCR.Immunochemistry was employed to assay the expression of TSLP and IL-4 proteins in corneal,conjunctival and subconjunctival tissues.Results Ocular inflammatory signs appeared 0.5 hours after ocular topical administration of extracting solution,including eyelid edema,conjunctival congestion,tears,scratching eyelids,etc.The symptoms lasted for 6-24 hours,with the model successful rate 80％.Real-time PCR indicated that the expression of IL-4 was absent in corneal epithelium in both model group and normal control group.The relative expression levels of TSLP mRNA in the corneal epithelium,conjunctiva and cervical lymph nodes in the model group were more (1.63±0.20)times,(2.71±0.48) times and (1.48 ±0.05) times than the normal control group,showing significant differences between the two groups (t =4.44,14.16,5.01,all at P＜0.05).Compared with the normal control group,the relative expression levels of IL-4 mRNA in the model group increased (2.94±0.39) times and (1.74±0.09) times,with significant differences between the two groups (t =9.92,14.54,both at P＜0.05).Immunochemistry assay showed that the expression of TSLP protein in the corneal and conjunctival epithelial cells were enhanced in the model group compared with the normal control group.In addition,an intensive expression of IL-4 protein was seen in subconjunctival tissue in the model group,while the expression of IL-4 was absent in the normal control group.Conclusions TSLP is mainly expressed in the cornea,conjunctiva and cervical lymph nodes of the mice with allergic conjunctivitis,suggesting that TSLP promotes the inflammatory process of cornea and conjunctiva;IL-4 is mainly expressed in conjunctiva,showing IL-4 participates in conjunctival inflammatory process.TSLP and IL-4 play synergistic roles in promoting the inflammatory process of ocular surface in the mice with allergic conjunctivitis,which may be new therapeutic targets.

Objective:To explore the roentgenographic and biomechanical characters of distraction osteogenesis(DO) in the treatment of mandibular defect.Methods:4 beagle dogs were used to establish 2.0 cm mandibular defect model,after 6 months, a 1.5 cm transport disc was surgically created adjacent to the defect area in an intraoral way, and intraoral device was placed on the transport disc and the base bone segments.A reconstructive plate was applied to stabilize the bone segments. After a 10 day latency period, the transport disc was advanced at a rate of 0.5 mm ? 2/day until the bone fragments were docked at the planned position.35 weeks after completion of distraction the animals were sacrificed,specimen retrieval,roentgenography and the stress testing were performed.Results:The regenerated segments were comparable with the corresponding segments of native mandible,and exact location of junction between the regerated and preexisting bone could not be determined easily. Roentgenographic revealed that the defects were reconstructed with outer cortical layer and trabecular medullary cavity of the bone.The regenerated segments remained less radiodense than the native mandible.Stress test demonstrated that the average ultimate strength of regenerated segmens was (69.4?19.2) MPa,that of the corresponding normal mandible was (86.9?31.9) MPa,and that of junction between transport disc and base bone was(46.9?8.4) MPa. Conclusion:Intraoral distraction osteogenesis may be feasible in the treatment of mandibular defect.

Objective:To describe the application of intraoral di st raction osteogenesis for correction of maxillofacial and mandibular deformities . Methods: 5 cases with serious maxillofacial or mandibula r deformities underwent distraction by using 2 types of intraoral distraction d evice.Mandibular lengthening and maxillary widening for micrognathia and maxilla ty constriction was performed in 1 case with Treacher Collions syndromes. M axillary distraction osteogenesis for maxillary hypoplasia in 2 cases.Simultaneo us maxillary and mandibular distraction in 1 case with hemifacial microsomia. T ransport distraction for mandibular body rectangle defect in 1 case. Results: Satisfactory morphologic results were achieved in all patients with good facial symmetry, ad equate occlusal relationship without any complication.Conclusions: Intraoral distraction osteogenesis provides a safe and effective treatment for the reconstruction of facial morphologic and occlusal relationshi p.

Objective:To study the ultrastructural characters and mineral content of the newly formed bone induced by distraction osteogenesis(DO) in the canine mandibular defects.Methods:4 beagle canines were used to establish 2.0 cm segmental mandibular defect surgically. Intraoral bifocal distraction osteogenesis was used to repaire the defects. After a 10-day latency, the transport disc was advanced at a rate of 0.5 mm? 2/day until the bone fragment was docked at the planned position. Specimen retrieval at 35 weeks after completion of distraction, scanning electron microscopy(SEM) analysis was then performed. The mineral content was measured by electron dispersive spectroscopy.Results:35 weeks after application of DO the mandibular defects were completely filled with regenerated bone. The regenerated bone was compact, sturdy and mature. The new bone was closed to the transport disk. The Ca/P content ratio was 1.80 in the regenerated bone and 2.02 in the transport disk.Conclusion: DO may induce new bone formation and may be used to repaire mandibular defects.

Objective To study the diagnostic value of endoscopy assisted by laparoscopy in patients with small intestinal bleeding. Methods In case of small intestinal bleeding it is hard to define the accurate etiological factor by routine examination. From 1994 to 2002 there were 14 patients with chronic me-lena or persisted melena complicated with chronic anemia and 2 cases of acute alimentary tract hematorrhea complicated with obvious hypovolemia. Results Endoscopies assisted by laparoscopy were accomplished in all of the 16 cases. Lesions were detected in 5 cases with laparoscopy directly, and in 11 cases the pathological changes were discovered by endoscopies assisted with laparoscopy . The pathologic results were leiomyo-sarcoma 1 cases, leiomyoma 4 cases, adenoma of small intestine , hemangioma , vascular malformation and capillary telangiectasia 2 cases each, and Meckels diverticulitis with hemorrhage 3 cases. Conclusion The diagnostic value of endoscopy assisted with laparoscopy is superior to the routine examination in detecting the small intestinal bleeding. This technique has the advantage of simple, less-traumatic and high sensitivity. It is worthy to popularize in clinical practice.

OBJECTIVE:To evaluate the status and tendency of the application of antihyperlipidemics drugs in Chongqing area. METHODS: The use of antihyperlipidemics drugs in 28 hospitals of Chongqing from 2004 to 2007 was analyzed statistically in respect of the consumption sum, DDDs and DDC. RESULTS: The mean annual incremental ratio of the consumption sum of antihyperlipidemics drugs reached over 33.80%. Simvastatin has been dominated the first place over the 4 years in terms of consumption sum and DDDs; the consumption sum of atorvastatin has been on the rise but that of Gemfibrozil decreased year on year with mean annual decrement of 60%. CONCLUSION: Statins assumed a dominant position among all the antihyperlipidemics drugs used in Chongqing area and its use has great potential.

BackgroundMonocyte chemotactic protein-1 (MCP-1)plays an important role in the tumor,inflammation,diabetic retinopathy and other neovascular disease,but the expression and the role of MCP-1 in the oxygen induced retinopathy(OIR) model have rarely been reported. Objective This study was to investigate the expression of MCP-1 in the retina development of newborn mouse and in mouse models with OIR.Methods C57BL/6J newborn mice were divided into two groups and 60 mice in each group.Mice in OIR group were exposed to 75％ oxygen for 5 days and then to room air.All mice in normal control group exposed to room air only.Ten mice in each group were randomly chosen and sacrificed at postnatal 5,7,12,14,17,21 days.The expression of MCP-1 in mouse retina was detected with the method of immunohistoehemistry and reverse transcription polymerase chain reaction(RT-PCR).Results MCP-1 positive cells were seen in normal mouse retina.Up-regulation of MCP-1 positive cells was detected both in 12 days in normal control group and in 14 days in OIR group.MCP-1 mRNA was detected in mouse retina at 5 days,and a transient up-regulation of MCP-1 mRNA was observed in 12 days in normal control group.MCP-1 mRNA in OIR group significantly increased in 14 days in comparison with the normal control group( P =0.028,P =0.001 ). Conclusions Expression of MCP-1 is detectable in whole retinal development procession of mice.A transient up-regulation of MCP-1 expression is detected in the critical period of retinal vascular development in mice models with OIR,which is closely related to the retinal vascular development and progression of retinal new vessels.