As an advanced conformal therapy, Intensity-modulated radiotherapy (IMRT) can increase the gain ratio of radiotherapy and improve the local control of the tumor. This paper applies genetic algorithm to optimization of IMRT inverse planning. The algorithm model and simulation result are introduced.

BACKGROUND:For severe thoracolumbar compression fracture (>1/3 compression), ideal therapeutic method is minimal y invasive internal fixation, which has good biomechanical functions. Moreover, bone graft is reliable. Injured vertebra reduction and bone graft stability achieved. Motor unit of spinal column and normal physiological function were retained, resulting in lessening nearby segmental degeneration.
OBJECTIVE:To discuss the design of single vertebrae internal fixation system and evaluate its biomechanical performance which apply to treat thoracolumbar compression fracture by endoscope.
METHODS:A brand-new single vertebrae internal fixation system was designed in accordance with data of anatomic measurement of adult thoracolumbar vertebra. Six fresh adult corpse specimens were prepared to produce models of L 1 compression fracture, and assigned to control group, fracture injury group, single vertebrae internal fixation system group, AF reduction internal fixation group and anterior plate internal fixation group.Three-dimensional movement range experiments were conducted separately.
RESULTS AND CONCLUSION:The biomechanical comparison showed that there was no significant difference in three-dimensional range of motion among single vertebrae internal fixation system group (anteflexion, left and right lateroflexion), AF reduction internal fixation group and anterior plate internal fixation group (P>0.05). However, range of motion significantly increased at backward extension, left and right rotation (P<0.05). Results suggested that the design of single vertebrae internal fixation system was novel and the system had good biomechanical performance at anteflexion, left and right lateroflexion. However, it needs to be improved in which lacks of stability of extension and rotation.

Objective To study the value of the technique of "Push-pull traction-relax homingrepeatedly confirmed" in the prevention of bile duct injury in LC. Methods From March 2001-August 2009, we applied this technique in 4800 cases of LC. The technique of "Push-pull traction" showed the structures of in the Calot's triangle. The technique of "relax homing" was to restore the cystic duct,hepatic duct and common bile duct to their original anatomical positions. The technique of "repeatedly confirmed" repeatedly identified the positions of the cystic duct, the common hepatic duct and the common bile duct. Results There was no bile duct injury. Conversion to open surgery happened in 118patients due to difficulties in identifying the Calot's triangle structures, bile duct stones, gallbladder cancer, and gallbladder-duodenal fistula. Conclusions The "Push-pull traction-relax homing-repeatedly confirmed" technique could effectively prevent bile duct injury in LC. The method is simple, easy to master and worthy of promotion.

BACKGROUNDWith the improvement of the surgical and anesthetic techniques, there are increasing numbers of elderly surgical patients with lung cancer. The purpose of this study is to examine the prognostic factors of surgical resection in patients more than 70 years of age.

METHODSData were retrospectively analyzed from 192 patients aged ≥70 years who underwent lung cancer surgery. Of these patients, 48.4% were in stage I, 20.8% in stage II, 19.3% in stage III, and 2.1% in stage IV. Patient demographics were the following: 79.2% male and 20.8% female; 21.9% ≥75 years older; and 11.5% had significant co-morbidities. Tumor characteristics: squamous cell carcinoma 49.0%, adenocarcinoma 35.9%, adenosquamous carcinoma 8.3%, small cell lung cancer 4.7%, others 2.1%.

OPERATIONSexploration 2.1%, wedge resection 8.3%, lobectomy 72.4%, more than lobectomy 12.5%, pneumonectomy 4.7%. Of these operations, 91.1% were radical surgery. The significance of prognostic factors was assessed by univariate and multivariate COX regression analyses.

RESULTSThe total 5-year survival rate was 33.5% in this series. Age, sex, symptom and co-morbidity had no impact on survival. Multivariable COX analysis demonstrated that incomplete resection (P=0.003), advanced surgical-pathological stage (P < 0.001) and other type of the tumor (P=0.016) were significant, independent, unfavorable prognostic determinants in patients.

CONCLUSIONSThoracic surgery is a safe and feasible approach in elderly patients with lung cancer. Every effort should be made to detect early stage patients who might benefit from surgical treatment. Lobectomy is still the ideal surgical option for elderly patients who are able to tolerate the procedure. More limited lung surgery may be an adequate alternative in patients with associated co-morbidities.

ObjectiveTo investigate the key compounds affecting the irritation and to clarify the effect of heating and the addition of ginger juice as the auxiliary material during the processing on the irritation of Magnoliae Officinalis Cortex（MOC） by comparing the irritation and composition of volatile oil in MOC and its different processed products. MethodVolatile oil in raw products， water-processed products， ginger-dried products， ginger-fried products（the amounts of ginger were 10%， 50%， respectively） of MOC were extracted by steam distillation and subjected to rabbit eye irritation experiment， and the volatile components of each sample were detected by gas chromatography-mass spectrometry（GC-MS）. Principal component analysis（PCA）and orthogonal partial least squares-discriminant analysis（OPLS-DA） were used to analyze the data of each sample by SIMCA 14.1. The relative contents of different processed products were compared two by two with those of and raw products or ginger-fried products， and the markers that might be related to the irritation were sorted out according to the principles of variable importance in the projection（VIP） value >1 and P<0.05， and the factors influencing the differences in irritation were analyzed. ResultCompared with the blank group， the administration groups all had irritation to the eyes of rabbits， and the degree of irritation was in the order of raw products>water-processed products>ginger-dried products>ginger-fried products（10%）>ginger-fried products（50%）. The results of PCA and OPLS-DA showed that there were differences in the volatile oil from raw products and different processed products. According to VIP value>1 and P<0.05， and combined with the results of eye irritation experiment， ten volatile compounds related to irritation changes were screened out. Among them， cis-cinnamaldehyde was only detected in raw products， the relative contents of β-caryophyllene， （+）-delta-cadinene， α-humulene， γ-muurolene， （-）-isoledene and citral all increased to different degrees， the contents of p-cymene， 1（10）-4-cadinadien-15-ol and β-eudesmol all decreased to different degrees. ConclusionThe irritation of MOC is reduced after heating and processing with ginger juice， and the synergistic effect of both is more effective for reducing irritation. Among the differential markers associated with changes in irritation， the increase in the relative content of citral is closely related to the addition of ginger juice， while the decrease in the relative contents of cis-cinnamaldehyde， p-cymene， 1（10）-4-cadinadien-15-ol is related to heating， and the changes of other components may be related to the synergistic effect of heating and ginger juice.