Objective To study the effects of using jaw tracking technique with Smart LMC algorithm on the absorbing dose of planning target volume (PTV) and organs at risk (OARs) in dynamic intensity-modulated radiation therapy (IMRT) for nasopharyngeal carcinoma (NPC).Methods Field fluencies of 10 cases of NPC patients were optimized using DVO algorithm on Eclipse TPS (11.0),and according to the same optimal fluence,MLC operation files were calculated using jaw tracking technique and jaw fixing technique respectively,dose distribution was calculated with AAA algorithm and jaw tracking IMRT plan (JT-IMRT) and jaw fixing IMRT plan (JF-IMRT) were generated respectively.Collimators' position at the plan implementation was observed,and the total number of plans' monitor units (MU),the dose of PTV,the absorb dose of OARs,and the actual fluence verification pass rate were compared.Results The collimators' opening gap distances in 166 control points of the JT-IMRT reduced in both X and Y directions in the field,compared to that of the JF-IMRT.Total number of the JT-IMRT's MU increased by 3.59％-11.63％.There was no statistical significant difference between the doses of the PTV.Statistical significance was found in the differences between maximum dose (Dmax) of brainstem,spinal cord,crystal,optic nerve,the mean dose (Dmean) and D50％ of parotid and their decreased values after therapy (t=5.70-8.66,P＜0.05).The actual fluence verification pass rate of the JT-IMRT was higher than that of the JF-IMRT.There was a significant difference between the results (t=5.18,P＜0.05).Conclusions The JT-IMRT plan of the smart LMC algorithm is more tolerant to the radiation leakage between inter-and intra-leaf.The dose of OARs is lower,while the dose calculation precision and the verification pass rate are higher,the actual radiation dose is more accurate and reliable.Therefore it is more suitable for clinical applications.

Objective To explore the clinical value of total hemihepatic vascular exclusion (THHVE) in right hepatectomy for hepatocellular carcinoma (HCC). Methods One hundred and twenty-three consecutive patients who underwent right hepatectomy for HCC between February 2006 and December 2008 were studied retrospectively. THHVE was used in 58 patients (group A) and Pringle maneuver in 65 patients (group B). The patient's demographics,surgical procedure and outcome were collected and compared between the two groups.ResultsThe tumor size was significantly bigger in group A than group B (7.69±3.70 cm vs.6.08±4.07 cm,P＜0.05).The vascular occlusion time in group A was significantly longer than groupB (28.55±8.67 min vs.19.85±6.71 min,P＜0.05). However, intraoperative blood loss in group A was significantly less than group B (304.31±270.36 ml vs.542.62±876.84 ml,P＜0.05),and the elevation of serum alanine aminotransferase (ALT) on day- 1,-3 and- 7 after operation in group A were significantly lower than group B (P＜0.05).The postoperative complication rate in group A was lower than group B (18.97％ vs.38.46％,P＜0.05).ConclusionTHHVE was a safe and efficacious technique in right hepatectomy for HCC.It significantly decreased blood loss,alleviated liver injury and reduced postoperative morbidity and mortality.

Objectives: To investigate the distribution of common pathogens and their antibiotic resistance from patiens with catheter related sepsis (CRS).Methods: Catheter bacteria cultrure and antibiotic sensitivity test were performed from 69 patiens with CRS.Results: The common pathogens in CRS were fungi (41.1%),Gram-positive cocci (35.6%)and Gram-negtive bacilli (23.3%). Non-C. albicans species were major pathogen (19/30 stranins).The most strains were staphylococcus epidermidis in Gram-positive cocci and the most of them were Methicillin resistant.No vancomycin resistant strains were found. The Gram negative bacilli were often resistant to third generation cephalosporens.Conclusions: The dorminant pathogens of CRS are fungi and gram positive cocci and we should pay more attention to pathogens of resistence to antibiotics. In order to control CRS, CVC must be used reasonably and shorten the duration of retention.

Objective To analyze variations of hepatic vein in healthy people with 64-slice spiral CT.Methods Seventy-five healthy subjects underwent multi-slice spiral computed(MSCT)hepatic venography.The anatomy of the junction of the hepatic veins with the inferior vena cava and the intrahepatic drainage territory of the hepatic veins and tributaries were evaluated.The hepatic veins were classified according to three anatomic classification(Nakamura's,Marcos's and Kawasaki's classification)methods respectively.Results There was a common trunk of the middle and left hepatic veins before joining the IVC in 86.7%(65/75)of the cases.In 13.3%(10/75)of the cases,the three main hepatic veins joined the IVC separately.The ratios of Nakamura's classification type A,B,C of hepatic veins were 49.4% (37/75),37.3%(28/75),and 13.3%(10/75)respectively.The ratios of Marcos's classification type A,B,C of hepatic veins were 56.0%(42/75),24.0%(18/75),and 20.0%(15/75)respectively. The ratios of Kawasaki's classification type Ⅰ,Ⅱ of hepatic vein were 40.0%(30/75)and 60.0% (45/75).Conclusion Multi-slice spiral CT hepatic venography can provide visualization of peripheral hepatic venous branches in details.

Objective To evaluate the shear stiffness of brain by MR elastography (MRE) in healthy Chinese volunteers and to assess the association between the cerebral shear stiffness and age. Methods Brain MRE studies were performed on 105 healthy volunteers. The shear stiffness of brain parencham was measured by local frequency estimation (LFE) algorithm. The differences of the shear stiffness between white matter(WM) and grey matter(GM) were analyzed by independent sample t test; the differences of brain parenchyma shear stiffness between male and female were estimated by independent sample t test. Spearman test was used to analyze the correlation between age and the shear stiffness of parenchyma; the volunteers were divided into two groups (age ≤ 40 and age > 40) and the correlation between age and shear stiffness of parencbyma in each group were analyzed separately. Results The shear stiffness of whiter matter [(23.1±5.7) kPa] was higher than that of grey matter[(11.3±2.6) kPa], and the difference was significant (t = 19.34, P < 0.01). In male, the shear stiffness of WM and GM was (23.4±5.8) kPa and (11.4±2.8) kPa respectively; while in female, it was (22.8±5.6) kPa and (11.1±2.5) kPa respectively. No sex differences were found in the stiffness of white matter or gray matter (t = - 0.534, - 0.606, P > 0.05). An age-dependent trend was observed in the stiffness of grey matter(r =0.315, P < 0.01),while not in whiter matter (r = 0.183, P > 0.05). When the shear stiffness of subjects no more than 40 years old was analysed, the age-dependent trend of shear stiffness was found both in white matter and gray matter(r = 0.251,0.235, P < 0.05); While in subjects over 40 years old, the age-dependent rend of shear stiffness was not found in white matter or gray matter(r = 0.181, - 0.001, P > 0.05). Conclusions The shear stiffness of WM is significantly higher than that of GM. No obvious sex difference was found in the stiffness of brain parenchyma. The shear stiffness of GM increases with age; the age-related increase of shear stiffness of WM was only found in subjects under 40 years old.

time (r = 0. 070, -0.003, -0. 195,0. 177,P 0.05). Conclusions Compared with omnivore's, the shear stiffness of brain parenehyma was lower in vegetarians. The shear stiffness of brain parenchyma may be affected by the diet.

Objective To evaluate the 80 mm volume shuttle cerebral CT perfusion(CTP) and 4D-CT angiography (CTA) in patients with stenosis or occlusion in Willis circle.Methods Conventional cerebral plain CT, 80 mm CTP and dynamic 4D-CTA were performed in 55 patients with unilateral MCA/ ICA stenosis or occlusion.The parameter maps of cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT) and time to peak (TTP) were analyzed.Meanwhile dynamic 4D-CTA images were also obtained.The significance of the differences of CBF, CBV, MTT and TTP between the affected side and the contralateral side was assessed using K Independent Samples analysis.Results In 40 patients with unilateral stenosis or occlusion of MCA/ICA, CTP was found abnormal in 36 patients.MTT and TTP of affected side [(7.18 ±1.34), (19.65 ±1.81) s] were significantly prolonged compared to contralateral side [(5.22±1.14) s, (17.62±1.65) s, X~2 =30.833,25.817, P<0.017].Centrum ovale or parietal lobe ischemic lesions were observed in 16 patients on CTP.In 15 patients with bilateral stenosis or occlusion of MCA/ICA, CTP was observed abnormal in 10 patients.CBF, CBV, MTT and TTP of affected side [(42.85 ±6.09) ml·100 g~(-1)·min~(-1), (2.63 ±0.42) ml·100 g~(-1), (11.27 ±1.43) s, (21.07 ±1.44) s)] were significantly different from those of contralateral side [(71.20 ±6.30) ml·100 g~(-1)·min~(-1), (2.29 ±0.15) ml·100 g~(-1), (3.38 ±0.61) s, (17.64 ±1.70) s (X~2 =17.314, 5.913,17.334,13.834,P<0.017)].On 4D-CTA covering 80 mm (0.625 mm×l28), unilateral stenosis of MCA were observed in 22 patients (13 right MCA and 9 left MCA), unilateral occlusion were observed in 5 patients (1 right MCA and 4 left MCA) and bilateral MCA stenosis/occlusion were observed in 9 patients.4D-CTA covering Willis cycle can display stenosis/occlsion of MCA as same as conventional CTA and DSA.Conclusion 80 mm volume shuttle CTP and 4D-CTA provide valuable information about the hemodynamic changes and the abnormalities of intracranial artery in patients with MCA/ICA stenosis or occlusion.

OBJECTIVETo analyze the prevalence of asthma and asthma related symptoms among children aged 0-14 years in three Chinese cities and to obtain a crude estimation of the trend of childhood asthma prevalence in China.

METHODSA cross-sectional, population-based survey of prevalence of asthma was conducted in children aged from 0 to 14 years in 3 major cities of China (Beijing, Chongqing, and Guangzhou) with different geographic locations. All the subjects were randomly selected by a multi-stage sampling method. Three to five schools and kindergartens in 2 urban districts in each city were randomly selected for the survey, and a validated questionnaire that included the core questions of the International Study of Asthma and Allergies in Childhood, Phase III questionnaire and several additional questions were used. All questionnaires were completed by parents or guardians of the selected children. Children whose parents responded affirmatively to the question "Has your child ever been diagnosed as asthma by a doctor" were recognized as victims of asthma.

RESULTSThe prevalence of asthma in Beijing, Chongqing, and Guangzhou was 3.15%, 7.45%, and 2.09%, respectively. These values were significantly higher than those obtained 10 years ago in the national epidemiological survey in 2000 which used the same method of investigation and the same diagnotic criteria (χ²=3.938, P=0.047; χ²=73.506, P≤0.001; χ²=11.956, P=0.001, in each city). Of the asthmatic children 57.21%, 69.91%, and 60.00% had their first attack before the age of 3 in Beijing, Chongqing, and Guangzhou, respectively. Wheezing was the primary clinical manifestation for all asthmatic children, followed by persistent cough and repeated respiratory infections. Both the prevalence of asthma and asthma-related symptoms were statistically higher in males than in females.

CONCLUSIONThe prevalence of childhood asthma is statistically higher than that 10 years ago in the three Chinese cities.

Asthma ; epidemiology ; Child ; Child, Preschool ; China ; epidemiology ; Female ; Humans ; Male ; Prevalence

Objective To investigate the value of MRI in thmmbolytic thempy of hyperacute cerebral arterial thrombosis.Methods One hundred and sixteen patients with acute cerebral arterial thrombosis were recruited.plain CT and multi.modal MRI were performed in all patients.Thirty-three patients with hyperacute cerebral infarction were treated bv recombinant tissue plasminogen activator(rt-PA) and followed-up periodically using MRI.Results The 33 patients with thrombolysis selected by MRI demonstrated clinical improvement.90 d moclified Rankin scale scores(mRs)were less than 2 and life quality Barthal indexes(BI)were from 80 to 100.The complication included one asymptomatic parenchymal hematoma(PH1)one weeks after thrombolytic therapy and 4(12.2%)hemorrhagic infarction(HI)6 to 24 hours after thrombolytic therapy.Condusions MRI has significant clinical value for the screening and follow-up of intravenous thrombolytic therapy of hyperacute ischemic stroke.MRI-based thrombolysis is a safe and effective method for hyperacute ischemic stroke.

PURPOSE: Hepatocellular carcinoma (HCC) is an aggressive disease with high recurrence rate. However, current staging systems were lack of predictive capacity for HCC recurrence. We aimed to develop prognostic nomograms based on inflammation-related markers for HCC patients underwent hepatectomy. MATERIALS AND METHODS: We recruited 889 surgically treated patients from two medical centers. Independent prognostic factors were identified by cox regression analyses. Nomograms for recurrence-free survival (RFS) and overall survival (OS) were established, and validated internally and externally. The performance, discrimination, and calibration of nomograms were assessed, and compared with existed staging systems. RESULTS: Neutrophil to lymphocyte ratio (NLR) and gamma-glutamyl transpeptidase to platelet ratio (GPR) were the two inflammation-related factor that independently correlated with survival. NLR, GPR, international normalized ratio (INR), microvascular invasion, satellite lesions, tumour number, tumour diameter, and macrovascular invasion were used to construct nomogram for RFS while GPR, total bilirubin, INR, α-fetoprotein, microvascular invasion, satellite lesions, tumour diameter, and macrovascular invasion were for OS. In the training cohort, the C-index of nomogram was 0.701 (95% confidence interval [CI], 0.669 to 0.732) for RFS and 0.761 (95% CI, 0.728 to 0.795) for OS. These results received both internal and external validation with C-index of 0.701 (95% CI, 0.647 to 0.755) and 0.707 (95% CI, 0.657 to 0.756) for RFS, and 0.706 (95% CI, 0.640 to 0.772) and 0.708 (95% CI, 0.646 to 0.771) for OS, respectively. The nomograms showed superior accuracy to conventional staging systems (p<0.001). CONCLUSION: The nomograms based on inflammation-related markers are of high efficacy in predicting survival of HCC patients after hepatectomy, which will be valuable in guiding postoperative interventions and follow-ups.
Bilirubin ; Blood Platelets ; Calibration ; Carcinoma, Hepatocellular ; Cohort Studies ; Discrimination (Psychology) ; Follow-Up Studies ; gamma-Glutamyltransferase ; Hepatectomy ; Humans ; Inflammation ; International Normalized Ratio ; Lymphocytes ; Neutrophils ; Nomograms ; Recurrence