Objective To optimize the application principles of gradient factors(GFs) in decompression algorithm by analyzing its law of regulation.Methods The saturated value of compartments was listed and the limits of decompression were calculated to evaluate the effect of GFs on safety and efficiency of decompression.The anchor point of GFs was changed.Results and Conclusion A higher GF was recommended in shallow and short dives, while in deep and long dives a moderate low GF and decompression by oxygen was preferred.The modification of the anchor points of GFs can increase the risk of decompression sickness and should be used with caution.

Background and purpose:Indensity modulated radiotherapy(IMRT) is an advanced method in radiotherapy field.Divect machine optimization technique is an good aritmetic for IMRT optimization.The purpose of this study was to compare the dosimetric differences between traditional technique and direct machine parameter optimization(DMPO) technique in the treatment of nasopharyngeal carcinoma(NPC) using step and shoot IMRT.Methods:Eleven patients of(NPC) were treated with step and shoot IMRT in Cancer Hospital,Fudan University from Feb.2005 to May 2006.Their plans(original plan,defined as treat) were archived for comparing with four kinds of IMRT plans(defined as DMPO100,DMPO90,DMPO80,DMPO70) with different predefined maximum number of segments(100,90,80,70,respectively),which were designed to use direct machine parameter optimization(DMPO) technique.We compared the total monitor units(MU),total segments,dose distribution and conformity index among the plans.Results:All the plans showed similar target coverage.Compared with traditional technique,IMRT plans with DMPO technique showed higher conformity index,and had similar uniformity except plan DMPO70.The dose distributions of DMPO100 and DMPO90 were similar or superior to the original plan(treat) in terms of critical organs.Without sacrificing plan quality,the total segments were about half of traditional plan if DMPO technique was used for planning.Moreover,the total monitor units(MUs) and the radiation time were decreased.Conclusions:Compared with traditional technique,plans designed with DMPO technique show sharp decrease in total segments without sacrificing plans quality in the treatment of nasopharyngeal carcinoma(NPC).The DMPO technique can also decrease the total MUs and radiation time.

Objective To investigate the role of mitochondrial respiratory chain (MRC) in induction of reactive oxygen species (ROS) by hyperbaric oxygen (HBO).Methods Superoxide anion (O·-2) specific fluorescence probe DHE and mitochondrial O·-2 probe Mito-SOX were used to label ROS in human umbilical vein endothelium cells(HUVEC) microscopically after HBO exposure.Results After HBO exposure, O·-2 increased (31±8)% and (137±19) % in whole cells and in mitochondria, respectively (P<0.01).These increments were suppressed by MRC complex Ⅱ inhibitor TTFA for (55±11)% in whole cells (P<0.05)and (61±8) % in mitochondria(P<0.01).Conclusion MRC may be the main source of ROS induced by HBO in HUVECs.

Through teaching on diving site,teachers can help students strengthen the un-derstanding and memory on theoretical knowledge,translate the knowledge into practical skills,and obtain primary medical supervisal capabilities. Scene teaching in diving unites can help students learn about the great achievements in the past and the present situations. Such understandings would be good for the students’fostering the responsibility and mission sense as a diving physician. In conclusion,it is very necessary to teach on diving site in the teaching of diving medicine,and such teaching should be kept as an essential part.

Objective To study the oxidative stress state of mice before and after air simulated diving. Methods Forty-eight mice were divided into 6 groups randomly. Every group was exposed to corresponding pressure for 60 minutes, twice a day for consecutive 3 days. Blood was obtained at the corresponding time to observe the changes of maleic dialdehyde, glutathione, glutathione-s-transferase, glutathione peroxidase, superoxide dismutase and catalase. Results Compared with the control, the activity of glutathione-s-transferase, glutathione peroxidase, superoxide dismutase, catalase and the level of glutathione were markedly inhibited and maleic dialdehyde increased in HO group and HA1 group (P

Background and purpose:There is controversial about dissecting the laryngeal nerve in operation of thyroid tumour in clinic. We adopted the methods of exposure of recurrent laryngeal nerve(RLN) to study their deficiencies and benefits. Methods:We reviewed review 456 cases of thyroid tumour who were operated. In 266 cases, RLN was unveiled generally. In 190 cases that RLN was not exposed, had subtotal thyroidectomy with protection of amatomical region.Results:RLN injury did not occur in the exposure group. 4 cases occurred in non-exposure group(3 cases of temporary RLN injury and 1 case of permanent RLN injury). Among the 3 cases of temporary RLN injury, one was caused by the large size of tumour, the other two were caused by the location of thyroid tumor. One case of permanent RLN injury was a case of reoperation for recurrence.Conclusions:The familiarity of the anatomy and variation of RLN, and the exposure of RLN in thyroid operation, can reduce the rate of the RLN injury.

OBJECTIVETo investigate the effect of reverse saphenous nerve neurocutaneous flaps for skin defects of forefoot.

METHODSIn the anatomic study, 50 cadaveric feet were injected with red latex and the anastomosis, distribution and external diameters of medialtarsal artery, medial anterior malleolus artery, medial plantar artery, the superficial branch of the medial basal hallucal artery and saphenousnerve nutritional vessels were observed. Based on anatomic research results, we designed the reverse saphenous nerve neurocutaneous flaps for repairing skin defects of forefoot.

RESULTSThe blood supply of reverse saphenous nerve neurocutaneous flaps were based on the vasoganglion, which consist of arterial arch at the superior border of abductor hallucis and arterial network on the surface of abductor hallucis around the saphenous nerve and medial pedis flap. From Oct. 2006 to Oct. 2011, the reverse saphenous nerve neurocutaneous flaps were used to repair skin defects of forefoot in 11 cases. The flap size ranged from 2.5 cm x 3.5 cm to 7.5 cm x 8.5 cm. The wounds at donor site were covered with full-thickness skin graft. All flaps survived completely with no ulcer at the donor site. 11 cases were followed up for 6 to 18 months( mean, 10 months). The skin color and texture were satisfactory. The patients could walk very well.

CONCLUSIONSIt is reliable to repair the skin defects of forefoot with reverse saphenous nerve neurocutaneous flaps. It is easily performed with less morbidity. This flap should be considered as a preferential way to reconstruct skin defects of forefoot.

Arteries ; anatomy & histology ; Cadaver ; Female ; Foot ; blood supply ; innervation ; Forefoot, Human ; injuries ; surgery ; Humans ; Male ; Muscle, Skeletal ; anatomy & histology ; Reconstructive Surgical Procedures ; Skin Transplantation ; methods ; Surgical Flaps ; blood supply ; innervation ; Transplant Donor Site ; surgery

Objective To explore the methods of repairing great toe soft tissue defect with the reverse medial pedis island flap with transverse artery of great toe.Methods This study was made up of two parts:an anatomical study and clinical application.In the anatomical study,49 cadaveric feet were injected with red latex and then anostomosis,distribution and external diameters of transverse artery of great toe,the deep branches of the first plantar metatarsal arteries and the deep branches of medial plantar artery were observed.From September 2006 to December 2012,8 cases of soft-tissue defects with the retrograde-flow medial pedis island flaps were harvested to cover the soft tissue defects of great toe.Soft tissue defect was form 2.5 cm × 3.5 cm-3.5 × 4.5 cm.Results There was an arterial circle under the first metatarsophalangeal joint which consisted of transverse artery of great toe,tibial proper plantar digital artery of great toe,fibular proper plantar digital artery of great toe and the distal part of first plantar metatarsal artery.This arterial circle under the first metatarsophalangeal joint and arterial network on the surface of abductor hallucis was responsible for the blood supply of the flap of medial pedis.The diameter of the pedicle was great,and the length of the pedicle was longer than in previous reported.In terms of clinical application,all patients were followed up with the mean of 10 months (range fromn 6-24 months).All flaps survived totally without diabrosis and swelling.The walking and weight-bearing were normal and the blood supply of foot was good.Conclusion Using of arterial circle under the first metatarsophalangeal joint,the medial pedis island flap has a reliable retrograde blood supply.The reverse point of the reverse medial pedis flap moved forward to th interphalangeal joint.This flap should be considered as a preferential way to reconstruct soft-tissue defects of the great toe.

To meet the requirements for the development of marine resources and military operations, divers usually dive deeper than the depth at which narcosis is present during air diving.Under this condition, heliox is required for this div-ing.Sofar, some countries have developed their own decompression tables for routine heliox diving.The best-known is tables from USA and France.In the preceding century, tables of Former Soviet Union and France used for routine heliox diving were introduced into China.On the basis of both types of tables,Chinese Navy developed their own tables for this purpose. In this paper, we summarized the characteristics of these tables from 5 countries and compared them in terms of structure, oxygen use, total decompression time, first stop and other features.This may provide a basis for future modification of ta-bles used in China and the development of new tables for routine heliox diving.

Background and purpose:The radiation should move at the same direction in accordance with the position of the couch during radiotherapy due to the different location of gross target volume. However, under the condition of the long distance movement of the couch, collisions between the gantry and the couch (or the patients) may happen. To avoid the collisions between the gantry and the couch, the motion area conlfiction between the gantry and the couch was analyzed.Methods:The distance from isocenter to the surface center of linear accelerator head, and the width and the thickness of treatment bed were measured when the treatment bed was empty, and gantry and collimator were at zero position. Forty sets of bed movement data were collected. The sum of squares ofX-andY-coordinates of reference point was calculated and compared with squares of rotation radius. Then, it was anticipated whether the linear accelerator head will collide with treatment bed. Finally, practical veriifcation was made.Results:Whether linear accelerator head collides with treatment bed depends on the difference between the sum of squares ofX-andY-coordinates and the squares of rotation radius. No collisions will happen when the sum of squares ofX-andY-coordinates is less than that of the squares of rotation radius.Conclusion:It is feasible to avoid collisions of linear accelerator head with treatment bed by comparing the sum of squares ofX-andY-coordinates of reference point with squares of rotation radius.