Effect of micro-implant anchorage combined with selective extracting maxillary first molar on second orthodontic treatment of malocclusion / 中华医学美学美容杂志

Objective To analyze the clinical effect of both micro-implant anchorage and selective extracting maxillary first molar to correct the failure of orthodontics.Methods From January 2006 to June 2012,24 cases who suffered from failure of orthodontics were treated in this department.To all patients,bilateral maxillary first molars were extracted,and micro-implant anchorage were planted into maxilla from buccal alveolar ridge to correct malocclusion acting as anchorages.Lateral cephalometric radiographs,intraoral photograph and facial photograph of every patient were taken before and after treatments; Their over bite and overjet molar relationship and incisors retraction were compared before and after treatments.Methods All the micro implant anchorages were sucessfuly implanted except two patients who experienced second operation owing to luxation of three implants.All the molars were strengthed and the profile improved along with their normal over bite and overjet.Conclusions The treatment of using micro-implant anchorage and selective extracting maxillary first molar is an ideal option of second orthodontics.Unconventional tooth extraction is used in this treatment.Micro implant anchorages are stable,acceptable and effective in clinical application.

Comparison study between main influencing factors and diurnal variation of net photosynthetic rate in different types of Pueraria thomsonii / 中国中药杂志

<p><b>OBJECTIVE</b>To study the diurnal variation of net photosynthetic rate (P(n)) and main influencing factors in different types of Pueraria thomsonii, aimed at providing the theoretical basis for breeding the fine varieties of P. thomsonii suitable for the local light condition.</p><p><b>METHOD</b>Diurnal variations of photosynthesis in leaves of different types of P. thomsonii were determined with the Li-6400 Portable Photosynthesis System.</p><p><b>RESULT</b>(1) Diurnal variation of P(n), transpiration Rate (T(r)), stomatal conductance (G(s)) in leaves of six varieties of P. thomsonii showed unimodal curve and asymmetric bimodal curve. Diurnal variation of water use efficiency (WUE), intercellular CO2 concentration (C(i)) showed single valley curve. Diurnal variation curve of stomatal limitation value (L(s)) was single peak and S-type. (2) P(n) in leaves of six varieties of P. thomsonii was positively correlated with photosynthetic active radiation (PAR), air temperature (T(a)), G(s), and negatively correlated with air relative humidity (RH), C(i), P(n) of all varieties were very significantly correlated with PAR, G(s).</p><p><b>CONCLUSION</b>Diurnal variations of photosynthesis in leaves of different types of P. thomsonii show significant difference. Jiuding, Chuanyu, Gange, Dijin No. 1 planted in Ya'an overcome "midday depression" phenomenon. Hechuan has the greatest photosynthetic potential, suitable for planting in forest understory and intercropping with high stalk to avoid the strong flashes. Planted in long-day region was beneficial to its growth. CO2 use efficiency of Geboshi No. 11 and Dijin No. 1 were significantly higher than that of the others. The accumulation efficiency of organics can be increased in cultivation management by fertilizing CO2.</p>