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Objective:To investigate the effect of bilateral repetitive transcranial magnetic stimulation (rTMS) on the pre-attentive processing of methamphetamine addicts.Methods:Forty methamphetamine addicts were screened and equally divided into the intervention group and the control group by random number table method.The intervention group was treated with bilateral simultaneous stimulation with 10 Hz on the left DLPFC and 1 Hz on the right DLPFC with 7 days of continuous intervention.The same scheme was used to intervene the control group, but with pseudo-stimulation. The changes of amplitude and latency of mismatch negative wave(MMN) before and after intervention were compared. SPSS 24.0 software was used for statistical analysis. Independent sample t-test was used for inter group comparison, and paired sample t-test was used for intra group comparison before and after intervention. Results:Before rTMS, there were no significant differences in MMN(F3, Fz, F4) amplitude (intervention group: (-0.90±0.28)μV, (-0.98±0.19)μV, (-0.96±0.19)μV; control group: (-0.92±0.21)μV, (-0.89±0.20)μV, (-0.94±0.16)μV)and latency(intervention group: (184.16±33.07)ms, (179.20±25.35)ms, (184.95±28.22)ms; control group: (184.91±26.96)ms, (180.99±25.29)ms, (181.55±23.19)ms) between the two groups (all P>0.05). After the intervention, there were significant differences in MMN(Fz, F4) amplitude(intervention group: (-1.38±0.16)μV, (-1.17±0.19)μV; control group: (-0.91±0.17) μV, (-0.99±0.16)μV) between the two groups (both P<0.01), but there were no significant differences in MMN (F3) amplitude(intervention group: (-1.01±0.59)μV; control group: (-0.80±0.50)μV), and in MMN (F3, Fz, F4) latency(intervention group: (177.38±26.45)ms, (172.17±23.87)ms, (179.84±23.60)ms; control group: (182.08±24.95)ms, (177.94±21.30)ms, (179.18±21.62)ms)between the two groups (all P>0.05). There were statistically significant differences in MMN( Fz, F4) amplitude (before-intervention: (-0.98±0.19)μV, (-0.96±0.19)μV; after-intervention: (-1.38±0.16)μV, (-1.17±0.19)μV)before and after intervention in the intervention group (both P<0.05), but there was no significant difference in MMN(F3) amplitude(before-intervention: (-0.90±0.28)μV; after-intervention: (-1.01±0.59)μV)before and after intervention in the intervention group ( P>0.05), and there were statistically significant differences in MMN(F3, Fz, F4) latency (before-intervention: (184.16±33.07)ms, (179.20±25.35)ms, (184.95±28.22)ms; after-intervention: (177.38±26.45)ms, (172.17±23.87)ms, (179.84±23.60)ms)before and after intervention in the intervention group(all P<0.05). After pseudo-stimulation, there were no statistically significant differences in MMN( F3, Fz, F4) amplitude(before-intervention: (-0.92±0.21)μV, (-0.89±0.20)μV, (-0.94±0.16)μV; after-intervention: (-0.80±0.50)μV, (-0.91±0.17)μV, (-0.99±0.16)μV)and latency (before-intervention: (184.91±26.96)ms, (180.99±25.29)ms, (181.55±23.19)ms; after-intervention: (182.08±24.95)ms, (177.94±21.30)ms, (179.18±21.62)ms) before and after intervention in the control group (all P>0.05). Conclusion:After repeated transcranial magnetic stimulation, the pre-attentive processing of the intervention group is improved, which shows that bilateral simultaneous stimulation of the rTMS program is effective.
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Objective:To investigate the serotype features of group B Streptococcus (GBS) vaginal colonization in late pregnancies and their relationship with early-onset neonatal GBS disease (GBS-EOD). Methods:Thirty-two strains were isolated from neonates delivered by GBS-positive mothers and hospitalized for GBS-EOD in Xiamen Maternal and Child Care Hospital from June 2016 to June 2018. Another 266 strains were isolated from vaginal samples from randomly selected late pregnant women who received antenatal screening and delivered in the same hospital during the same period with an allocation ratio of 12∶1. A total of 298 strains from mothers and 32 strains from neonates were involved. Every isolate was serotyped with latex agglutination assay. GBS infection caused by eleven serotypes and the correlation between GBS serotypes in late pregnant women and neonatal GBS-EOD were analyzed. Qualitative variables were compared using Chi-square or Fisher's exact test. A correlation analysis was presented by the column contact number C. Multiple analysis of multiple sample rates was performed with Post hoc testing. Differences between groups were analyzed according to the adjusted standardized residual. Results:A total of nine serotypes were identified among the 298 strains isolated from the mothers. The most prevalent serotype wasⅢ [55.0% (164/298)], followed byⅠb [16.4% (49/298)], Ⅰa [11.1% (33/298)], Ⅴ [9.4% (28/298)], Ⅱ [5.0% (15/298)], non-typable [NT, 1.0% (3/298)], and Ⅵ, Ⅷ and Ⅸ [0.7% (2/298) in each]. Neither Ⅳ nor Ⅶ serotype was identified. The 32 strains isolated from neonates with GBS-EOD belonged to five serotypes, which were Ⅲ [18/32 (56.3%)], Ⅰa [8/32 (25.0%)], Ⅰb [3/32 (9.4%)], Ⅱ [2/32 (6.2%)] and Ⅴ [1/32 (3.1%)]. The positive rates of GBS Ⅲ serotype in neonates with pneumonia, sepsis, and meningitis were 6/13, 7/14, and 5/5. However, no statistically significant difference was observed in the distribution of the five serotypes in GBS-EOD neonates ( P=0.654). Thirty neonates (93.7%) were cured, while two (6.3%) died. There were statistically significant differences among neonatal GBS-EOD caused by vertical transmission with Ⅰa, Ⅰb, Ⅱ, Ⅲ and Ⅴ, Ⅵ, Ⅷ, Ⅸ and NT serotypes ( P=0.046, contingency coefficient: 0.183). Further analysis showed that the adjusted absolute value of the standardized residual of serotype Ⅰa was 2.7 (>2), and the difference was statistically significant. However, the adjusted absolute value of the standardized residual of serotype Ⅲ was only 0.1, which was not statistically significant. Conclusions:Serotype Ⅲ is the most prevalent GBS serotype in late pregnant women and GBS-EOD neonates, and also the predominant serotype in infants with early-onset meningitis. Serotype Ⅰa could be highly vertically transmitted, while the virulence of serotypes Ⅲ and Ⅰa strains of GBS are the strongest.
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Objective:To explore the clinical efficacy and adverse reactions of the combination of external beam radiotherapy followed by three-dimensional intracavitary brachytherapy in patients with inoperable locally advanced rectal cancer.Methods:Clinical data of 11 patients with inoperable locally advanced rectal cancer, 7 male and 4 female, admitted to China-Japan Union Hospital of Jilin University from 2013 to 2015 were retrospectively analyzed. All patients received pelvic external irradiation (50 Gy in 25 fractions), followed by a three-dimensional intracavitary brachytherapy boost (15-20 Gy in 3-4 fractions, 1 fraction/week). External beam radiotherapy was used to boost the dose to the perirectal lymph nodes (60-66 Gy in 30-33 fractions). All patients received concurrent chemotherapy with Capecitabine during external beam radiotherapy. Efficacy evaluation was performed using the RECIST standard. Survival and local control rates were calculated using the Kaplan- Meier method. Early and late radiotherapy responses were assessed using the RTOG lesion grading criteria. Results:The CTV D 90% EQD 2 Gy of HDR 3D-ICBT among 11 patients was (21.3±1.60) Gy. The complete response (CR) and partial response (PR) rates were 64% and 27%, respectively, yielding an objective response rate (CR+PR) of 91%. With a median follow-up time of 36 months, the 1-, 2-, and 3-year overall survival rates were 82%, 64% and 46%, respectively. The 1-, 2-, 3-year disease-free survival rates were 64%, 45% and 27%, respectively. The 3-year local control rate was 46%. One patient presented with lung metastases after 8 months, 7 patients experienced grade 1-2 acute intestinal reactions and 5 patients developed grade 1-2 acute bladder reactions, only one patient had grade 2 myelosuppression; long-term grade 1-2 intestinal reactions occurred in 5 patients, and 1 patient had long-term grade 1-2 bladder reaction. All the radiation-induced toxicities were alleviated by medication administration. Conclusions:External beam radiotherapy followed by three-dimensional intracavitary brachytherapy can be a safe and effective surrogate in patients with inoperable locally advanced rectal cancer, which yields reliable clinical efficacy and tolerable adverse reactions.
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This paper made a detailed interpretation about the radiobiology-related contents in the ICRU report No.89,aiming to provide reference to resolve the problems related to radiobiology for the colleagues occupied in the brachytherapy for cervical cancer.
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Objective To investigate the application of superficial brachytherapy in the treatment of the upper arm skin invasion of breast cancer. Methods This study was conducted on a female patient with ipsilateral chest wall, axillary, and clavicle recurrence, and circumferential skin and subcutaneous soft tissue invasion in the ipsilateral upper arm after modified radical mastectomy for breast cancer. The upper arm lesions were treated with 192Ir high-dose-rate superficial brachytherapy at a dose of 50 Gy in 25 fractions. Dosimetric parameters were compared between superficial brachytherapy and electron irradiation plan. Treatment outcomes and adverse reactions were observed during and after treatment. Results The heterogeneity index(HI)for target volume was 1.62 and 1.94 in superficial brachytherapy and electron irradiation plan, respectively. The D90,D100, and V150%for clinical target volume were higher in superficial brachytherapy than in electron irradiation plan(205 vs. 189 cGy;163 vs. 110 cGy;6.3% vs. 3.23%). The D0.1,D1, and D2for the humerus were also higher in superficial brachytherapy than in electron irradiation plan(155 vs. 80 cGy;147 vs. 55 cGy;145 vs. 36 cGy)and much lower than the bone tolerance dose in both treatments. The lesions partially subsided after superficial brachytherapy. The main adverse reaction was grade 2 radiation dermatitis. Conclusions Compared with electron irradiation plan, superficial brachytherapy is a simple and effective approach for irradiation of shallow target volume with a large curvature, such as circumferential upper arm skin invasion of breast cancer. Superficial brachytherapy achieves satisfactory homogeneity and dose distribution.
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Objective:To explore the curative effect and toxic and side effects of Xihuang Capsule in the patients with advanced esophageal cancer treated with chemoradiotherapy, and to clarify its mechanism.Methods:The patients with advanced esophagealcancer without treatment were selected.The patients treated with Xihuang Capsule combined with concurrent chemoradiotherapy were defined as combination treatment group(n=27), and then other 27 patients were randomly selected from 87 patients treated with concurrent chemoradiotherapy alone as chemoradiotherapy group.The observation time was 90 d from the begining of chemotherapy.The differences in KPS, degree of dysphagia, incidence, occurrence time and degrees of acute radiation esophagitis of the patients in two groups were compared, and local control of tumor was analyzed.Results: After treatment, the KPS scores of the pateints in two groups were decreased, and the KPS score in combined treatment group was significantly higher than that in chemoradiotherapy group (P0.05).Conclusion:Xihuang Capsule can improve the quality of life, reduce dysphagia degree and the incidence of acute radiation esophagitis,and delay the occurrence time;it can be used as an effective auxiliary treatment of advanced esophageal cancer.
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Objective To perform the main application of MRI arterial spin labeling (ASL) in cerebral blood flow (CBF) on hippocampus of patients with temporal lobe epilepsy for quantitative measurement,to assess the relationship between temporal lobe epilepsy occurrence and hippocampal perfusion and to explore the critical value of hippocampal CBF predict the temporal lobe epilepsy early.Methods Forty-two subjects by video EEG (VEEG) and conventional MR sequences screend were divided into 3 groups eventually,namely group of healthy control,the group with one temporal lobe abnormal discharge,that conventional MRI in hippocampus is not abnormal and the last group with one side hippocampus sclerosis confirmed by conventional MRI in temporal lobe epilepsy patients,then for the hippocampal 3D ASL examination.We provided six same size regions of interest (ROI) in the hippocampal head,body,tail respectively with the best level display to measure and record bilateral hippocampal cerebral blood flow values (CBF values) of every subject,and to explore the relationship between the cerebral blood flow value in the hippocampus and temporal lobe epilepsy.Results Mean cerebral blood flow (CBF) value of each subject's unilateral hippocampus was calculated.The average CBF value of the hippocampus in the healthy control group was 53.82 ± 0.98ml/(100g · min).The average CBF of the hippocampus in epileptic unilateral abnormal discharge group with the ipsilateral and contralateral were 49.12 ± 5.31ml/(100g · min) and 55.99 ± 1.65ml/(100g · min).The average CBF of the hippocampus in epileptic unilateral hippocampal sclerosis group with the ipsilateral and contralateral were 39.57 ± 2.08ml/(100g · min) and 48.06 ± 1.74ml/(100g · min).Then pairwise comparison of the unilateral hippocampal average CBF value among the 3 groups of experimenters in different groups was performed.The results showed that in the eight times,the first six times had statistically significant differences.Comparing between the healthy control group and epilepsy unilateral temporal lobe abnormal discharge group,to calculates the best critical point by the ROC curve,the cut-off value was 46.76.Conclusion Magnetic resonance arterial spin labeling (ASL) technique can evaluate the cerebral blood flow in the hippocampus of patients with temporal lobe epilepsy by quantitative measurement of hippocampal CBF value.The changes of hippocampal perfusion in patients with temporal lobe epilepsy should be preceded by the changes of imaging.ASL quantitative measurement of hippocampal CBF value is helpful for early diagnosis and treatment of temporal lobe epilepsy.
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Objective To investigate the clinical application of Utrecht applicator in three-dimensional image-guided brachytherapy (3D-IGBT) for locally advanced cervical cancer,as well as its application discipline in intracavitary/interstitial (IC/IS) therapy.Methods A retrospective analysis was performed for the clinical data of 45 patients with locally advanced cervical cancer who received radical radiotherapy,and the patients received external beam radiotherapy followed by 3D-IGBT.A total of 130 times (n =45) of IC/IS therapy were performed,and the patients who received such therapy were all enrolled.The patients who met the target dose fractionation defined in the plan were enrolled as group A (n=37,86 times),and the other patients were enrolled as group B (n=22,44 times).Two groups difference was analyzed with Group t-test.Results The frequencies of use of 15-,20-,and 25-mm ovoids by the applicator were 50.0％,20.0％,and 30.0％,respectively,and the 30-mm ovoid was not used.A total of 499 needles were used,and the frequencies of use of 6,7,10,and 11 insertion holes were 23.1％,21.2％,21.2％,and 24.1 ％,respectively.Group A had a significantly lower mean number of the needles than group B (3.7 vs.4.2,P=0.008).Compared with group B,group A had a significantly lower mean high-risk clinical target volume (CTV)(40.71±18.43 cm3 vs.51.81±14.74 cm3,P=0.001),as well significantly lower width and height of high-risk CTV (P=0.011 and 0.006),but the thickness of high-risk CTV was similar between the two groups (P=0.595).The difference between height and insertion depth (DH) was similar between the two groups (P=0.366).Group A had a smaller difference between width and pinhole distance Dw than group B (P=0.007).Conclusions When IC/IS therapy is performed for locally advanced cervical cancer,the 15-,20-,and 25-mm ovoids of Utrecht applicator and 6,7,10,and 11 insertion holes are frequently used.When the number of needles is no less than 4 and the depth is no less than 3 cm,width is the major factor which affects the planned dose.
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Objective To investigate the dosimetric differences between Utrecht applicator and ring applicator in three-dimensional (3D) conformal brachytherapy for locally advanced cervical cancer.Methods Twenty-five patients with locally advanced cervical cancer were treated with magnetic resonance imaging-guided 3D conformal brachytherapy.Utrecht applicator and ring applicator were used interchangeably for 96 cycles.Patients were divided into two groups according to the type of applicator.Each group received 48 cycles of treatment, in which ring applicator was first applied for 26 cycles and Utrecht applicator was first applied for 22 cycles.High-risk clinical target volume ( HR-CTV) , width, thickness, and D90 at the point A level, D2 cm3 of organs at risk (OARs), V7 Gy , W7 Gy,A, V7 Gy ,A, and W/T7 Gy were evaluated and analyzed using paired t-test.Results There were no significant differences in HR-CTV and the width, thickness, and D90 at the point A level between the Utrecht group and the ring group ( P=0.487;P=0.340;P=0.857;P=0.921);there were no significant differences in D2 cm3 values of bladder, rectum, sigmoid, and bowel between the two groups ( P=0.136;P=0.802;P=0.985;P=0.458);there were no significant differences in V7 Gy and T7 Gy,A between the two groups ( P=0.076;P=0.435) .The Utrecht group had a significantly larger W/T7 Gy,A than the ring group ( P=0.002 ) .Conclusions Utrecht applicator is appropriate for patients with relatively large width and width/thickness ratio of HR-CTV at the point A level.
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Objective To explore the dosimetric advantages of computed tomography-based and ultrasound-guided three-dimensional image-quided brachytherapy (3D-IGBT) combined with intracavitary/interstitial (IC/IS) brachytherapy for locally advanced cervical cancer.Methods A total of 45 patients with FIGO (2009) stage ⅠB2-ⅣA locally advanced cervical cancer who received radical external beam radiotherapy and 3D-IGBT combined with IC/IS brachytherapy in our hospital from 2013 to 2014 were analyzed.After the treatment with 192Ir-based IC/IS brachytherapy,patients had needles removed from the original images and received treatment only from IC radiation sources.Dosimetric differences in the planning D90 for high-risk clinical target volume (HR-CTV),D90 for intermediate-risk CTV (IR-CTV),and D2 cm3 for the bladder,rectum,sigmoid colon,and small intestines were determined and analyzed by paired t-test.Results A total of 260 after-loading treatment plans,including IC/IS treatment plans for 130 patients and IC treatment plans for 130 patients,were made.The D90 for HR-CTV and D90 for IR-CTV in the IC/IS brachytherapy group were significantly higher than those in the IC brachytherapy group (P =0.000;P =0.000).Moreover,the average D2cm3 values for the bladder and rectum were significantly reduced in the IC/IS brachytherapy group compared with those in the IC brachytherapy group (P =0.000;P =0.006).Conclusions The 3D-IGBT combined with IC/IS brachytherapy not only achieves a higher dose for the target volume,but also reduces the radiation dose to the bladder and rectum in the treatment of locally advanced cervical cancer.
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Objective To evaluate the effect of bladder volume change on the doses to normal tissues in cervical cancer patients undergoing external three-dimensional conformal radiotherapy (3DRT)plus 3D conformal brachytherapy (3DCBT).Methods The study included 56 patients with cervical cancer who were admitted to our hospital from 2012 to 2013 and received radical external 3DRT and 3DCBT.During 3DCBT,the doses to 0.1,1.0,and 2.0 cm3(D0.1 cm3,D1.0cm3,and D2.0cm3,respectively) for the rectum,small intestine,sigmoid colon,and bladder under different bladder filling status (empty,50,100,and 150 ml) were compared and analyzed by paired t-test.Results The rectum D0.1cm3 with bladder volumes of 50and 100 ml were significantly reduced compared with that with an empty bladder (P =0.000,0.000).The D0.1 cm3,D1.0cm3,and D2.0cm3 for the small intestine with bladder volumes of 50,100,and 150 ml were significantly reduced compared with those with an empty bladder (P =0.008,0.000,0.000 and 0.000,0.000,0.000 or 0.000,0.000,0.000).The D0.1 cm3,D1.0cm3,and D2.0cm3 for the bladder with bladder volumes of 100 and 150 ml were significantly increased compared with those with an empty bladder (P =0.000,0.000 and 0.000,0.000 or 0.000,0.000).Conclusions The doses to the bladder and small intestine are influenced by different bladder filling status,but the doses to the rectum and sigmoid colon show no significant variation.The increase in bladder volume is helpful in reducing the dose to the small intestine.Without any change in the bladder dose,the bladder volume of 50 ml is more beneficial to reduce the dose to the small intestine than those of 100 and 150 ml.
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Objective To compare target volume and dosimetry between computed tomography (CT)?and magnetic resonance imaging (MRI)?guided three?dimensional (3D) conformal brachytherapy for locally advanced cervical cancer, and to provide evidence for optimization of the image?guided approach and improvement of treatment regimen. Methods Thirteen patients with locally advanced cervical cancer who were treated with radical radiotherapy in our hospital in 2014 were enrolled as subjects. All patients received MRI?guided 3D conformal intracavitary/ interstitial brachytherapy. All patients received MRI and CT scans for each brachytherapy fraction, based on which the target volume delineation, intracavitary/ interstitial regimen design, and intracavitary?only treatment regimen design were performed. Comparison of data between MRI and CT scans was performed using paired t test. Results The width and volume of the high?risk clinical target volume ( HR?CTV) were significantly smaller in the MRI simulation than in the CT simulation ((38.0±9?? 4) mm vs. (45.1±8?? 7) mm, P= 0?? 000;(34.2±15?? 3) cm3 vs. (42.9±20?? 4) cm3 , P= 0?? 002), and the width, thickness, and volume of the intermediate?risk clinical target volume (IR?CTV) were also significantly smaller in the MRI simulation than in the CT simulation ((58.8±9?? 4) mm vs. (65.4±10?? 3) mm, P= 0?? 000;(34.8±6?? 3) mm vs. (37.5±6?? 3) mm, P= 0?? 001;(90.9±28?? 5) cm3 vs. (109.0±36?? 4) cm3 , P= 0?? 000). The D90 values for HR?CTV and IR?CTV were significantly higher in the MRI simulation than in the CT simulation (87?? 6 Gy vs. 85?? 8 Gy, P= 0?? 013;67?? 7 Gy vs. 66?? 3 Gy, P= 0?? 005), while the average D2 cm3 values for the bladder and rectum were significantly lower in the MRI simulation than in the CT simulation ( 73?? 1 Gy vs . 75?? 5 Gy , P= 0?? 011 ; 61?? 0 Gy vs . 65?? 7 Gy , P= 0?? 000 ) . Conclusions Compared with the MRI simulation, the CT simulation overestimates the width of target volume. MRI has substantial advantages in dosimetry for target volume and normal tissues. The intracavitary/ interstitial treatment can make up the reduced dose for the target volume resulting from the CT simulation.
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Objective To explore the correlation between the dose measured in the rectum and reference dose in three?dimensional brachytherapy ( 3DBT ) for cervical cancer, and to evaluate the significance of the dose measured in the rectum. Methods Fifty patients receiving radiotherapy for cervical cancer were selected, and 3DBT was performed after pelvic external beam radiotherapy. According to the rectal monitoring method recommended in the report ICRU38, in vivo monitoring was applied to obtain the dose measured in the rectum, reference point dose ( DICRU ) , and D2 cm3 , and the planned dose was obtained from the planning system. The differences in these values were determined by the paired t?test and correlation analysis was performed with Pearson test. Results The dose measured in the rectum was higher than the planned dose (3. 48 vs. 3. 25,P=0. 000), and lower than DICRU(3. 48 vs. 3. 71,P=0. 000) and D2 cm3(3. 48 vs. 3. 87,P=0. 002). A linear relationship existed between the dose measured in the rectum and the planned dose, with a deviation percentage of-20% to 40% and an average deviation of 8. 16%;63%of the patients with cervical cancer had a deviation of<± 10%;the maximum deviation was 60%. The dose measured in the rectum had a strong correlation with DICRU(r=0. 722), but a weak correlation with D2 cm3 ( r=0. 284) . Conclusions During 3DBT for cervical cancer, the dose measured in the rectum has certain deviations, but has a linear correlation with the planned dose. Both the dose measured and the planned dose underestimate the dose at the reference point in the rectum, and in vivo rectal monitoring may be an effective method for quality control.
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Objective To investigate the dose-response of micronuclei (MN) frequency in the lymphocytes irradiated with or without combination of α-particles and γ-rays. Methods Human lymphoblast cells HMy2.CIR were irradiated with 0 - 1 Gy of α-particles,0 - 5 Gy of γ-rays,and 0.025 -0.5 Gy of α-particles followed by different doses of γ-rays,respectively.The micronuclei (MN) in the irradiated cells were measured with the cytokinesis block technique,and the dose-responses of MN were established under different irradiation conditions.Results For γ-ray irradiation,the dose-response of MN was well-fit by the linear-quadratic model with an equation Y =c + αD + βD2.For α-particle irradiation,the MN induction increased linearly with the dose less than 0.250 Gy. But when the dose of α-particles increased continually,the dose-response curve bended and could be well fit with the BaD model Y =c + αD + σ[ 1 - exp( - δD) ] exp( - βD) where radiation-induced bystander effect (RIBE) was indicated.For the combined exposure,the dose-response of MN was similar to that of γ-irradiation when the dose of α-particles was lower than 0.1 Gy,but it was similar to that of α-irradiation when the dose of α-particles was higher.When the dose of α-particles was 0.2 and 0.5 Gy,MN induced by the mixed radiation were significantly higher than the sum of corresponding irradiation alone ( t =5.22 - 11.86,P ＜ 0.05 ).Conclusions The radiation damage of α-particles differs from that of γ-rays,where RIBE may be involved.The combination irradiation of α-particles and γ-rays has a synergistic effect on radiation damage of lymphoblast cells.