Effect of cervical pillow in phacoemulsification surgery for age-related cataract patients: a prospective randomized controlled study.

PURPOSE: To explore the application effect of cervical pillow in phacoemulsification surgery for age-related cataract patients. METHODS: 104 cases of age-related cataract patients admitted to our hospital in June 2023 were enrolled and divided into the control group (traditional supine position) and the experimental group (the cervical pillow supine position) by the digital parity method (52 cases per group). The two groups were evaluated for the discomfort score, the satisfaction of patients and doctors, the head displacement rate, the number of displacement, the operation time and the time of body position during the operation and after the operation. RESULTS: There was no significant difference in the gender (P = 0.84), age (P = 0.86), course of disease (P = 0.82) and the time spent on position placement (P = 0.15) of the two groups. The patient in the experimental group had lower discomfort score (P = 0.0001), higher patients satisfaction (P = 0.0001) and higher doctors satisfaction (P = 0.0001) than patients in the control group. There was no significant difference between the experimental group and the control group in the proportion of intraoperative (P = 0.36) and postoperative pain (P = 0.65). Besides, the number of head transfers (P = 0.001), number of head shifts (P = 0.0001), the surgical time (P = 0.0001) and laparoscopic time (P = 0.0001) in the experimental group were significantly lower than those in the control group. CONCLUSION: The additional cervical pillow for age-related cataract patients in the traditional supine position during the operation will not increase the preparation time before the operation, but will help improve the patient satisfaction, improve the comfort and maintain a good position of the operative eye field, bringing obvious comfort and smooth operation for the surgeon in the operation, thus reducing the risk of the operation, shortening the operation time.

Clinical treatment considerations in the intensity-modulated radiotherapy era for parotid lymph node metastasis in patients with nasopharyngeal carcinoma.

PURPOSE: No specific irradiation guidelines have been proposed for parotid lymph node (PLN) metastasis in patients with nasopharyngeal carcinoma (NPC). This study aimed to explore the dose prescription and target delineation for PLN metastasis in patients with NPC. METHODS: With the NPC database from a big-data platform, 10,685 patients with primarily diagnosed, non-distant metastatic, histologically proven NPC and treated with intensity modulated radiotherapy (IMRT) at our center from 2008 to 2019 were reviewed and those with PLN metastasis were enrolled in this study. Dosimetry parameters were collected from the dose-volume histograms (DVH). The primary endpoint was overall survival (OS). Least absolute shrinkage and selection operator regression (LASSO) was operated for variable selection. Multivariate Cox regression analysis was applied to identify the independent prognostic factors. RESULTS: PLN metastases were identified in 275/10685 (2.5%) patients. Of 367 positive PLN, 199 were in superficial intra-parotid, followed by 70 in deep intra-parotid, 54 in subparotid and 44 in subcutaneous pre-auricular. Better survival outcome was observed in PLN-radical IMRT group, compared with PLN-sparing group. In 190 patients received PLN-radical IMRT, multivariate analysis revealed that D95% of level VIII > 55 Gy was an independent beneficial prognostic factor for overall survival (OS), progression-free survival (PFS), distant metastasis-free survival (DMFS), and parotid relapse-free survival (PRFS). CONCLUSION: Based on the distribution pattern of PLN metastasis in NPC and the result of dose-finding study, involving the ipsilateral level VIII into low-risk clinical target volume (CTV2) is recommended for NPC with PLN metastasis.

Hyperfractionation compared with standard fractionation in intensity-modulated radiotherapy for patients with locally advanced recurrent nasopharyngeal carcinoma: a multicentre, randomised, open-label, phase 3 trial.

BACKGROUND: Reirradiation in standard fractionation for locally advanced recurrent nasopharyngeal carcinoma after a previous course of high-dose radiotherapy is often associated with substantial late toxicity, negating its overall benefit. We therefore aimed to investigate the efficacy and safety of hyperfractionation compared with standard fractionation in intensity-modulated radiotherapy. METHODS: This multicentre, randomised, open-label, phase 3 trial was done in three centres in Guangzhou, China. Eligible patients were aged 18-65 years with histopathologically confirmed undifferentiated or differentiated, non-keratinising, advanced locally recurrent nasopharyngeal carcinoma. Participants were randomly assigned (1:1) to either receive hyperfractionation (65 Gy in 54 fractions, given twice daily with an interfractional time interval of at least 6 h) or standard fractionation (60 Gy in 27 fractions, given once a day). Intensity-modulated radiotherapy was used in both groups. A computer program generated the assignment sequence and randomisation was stratified by treatment centre, recurrent tumour stage (T2-T3 vs T4), and recurrent nodal stage (N0 vs N1-N2), determined at the time of randomisation. The two primary endpoints were the incidence of severe late complications defined as the incidence of grade 3 or worse late radiation-induced complications occurring 3 months after the completion of radiotherapy until the latest follow-up in the safety population, and overall survival defined as the time interval from randomisation to death due to any cause in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, NCT02456506. FINDINGS: Between July 10, 2015, and Dec 23, 2019, 178 patients were screened for eligibility, 144 of whom were enrolled and randomly assigned to hyperfractionation or standard fractionation (n=72 in each group). 35 (24%) participants were women and 109 (76%) were men. After a median follow-up of 45·0 months (IQR 37·3-53·3), there was a significantly lower incidence of grade 3 or worse late radiation-induced toxicity in the hyperfractionation group (23 [34%] of 68 patients) versus the standard fractionation group (39 [57%] of 68 patients; between-group difference -23% [95% CI -39 to -7]; p=0·023). Patients in the hyperfractionation group had better 3-year overall survival than those in the standard fractionation group (74·6% [95% CI 64·4 to 84·8] vs 55·0% [43·4 to 66·6]; hazard ratio for death 0·54 [95% CI 0·33 to 0·88]; p=0·014). There were fewer grade 5 late complications in the hyperfractionation group (five [7%] nasal haemorrhage) than in the standard fractionation group (16 [24%], including two [3%] nasopharyngeal necrosis, 11 [16%] nasal haemorrhage, and three [4%] temporal lobe necrosis). INTERPRETATION: Hyperfractionated intensity-modulated radiotherapy could significantly decrease the rate of severe late complications and improve overall survival among patients with locally advanced recurrent nasopharyngeal carcinoma. Our findings suggest that hyperfractionated intensity-modulated radiotherapy could be used as the standard of care for these patients. FUNDING: Key-Area Research and Development of Guangdong Province, the National Natural Science Foundation of China, the Special Support Program for High-level Talents in Sun Yat-sen University Cancer Center, the Guangzhou Science and Technology Plan Project, and the National Ten Thousand Talents Program Science and Technology Innovation Leading Talents, Sun Yat-Sen University Clinical Research 5010 Program.

Special type of distal junctional failure exhibits pelvic incidence changes: sacroiliac joint-related pain following lumbar spine surgery.

Background: Currently, change in pelvic incidence (PI) in patients after spinal surgery have not been associated with clear clinical symptoms. This study sought to compare changes in the sagittal parameters of different patients before and after thoracolumbar spine surgery, the relationship between PI change and sacroiliac joint pain (SIJP) after surgery was clarified, and the correlation between PI change and sacroiliac joint (SIJ) activity was verified. Methods: This study retrospectively analyzed the data of patients who underwent thoracolumbar fusion at Sun Yat-sen Memorial Hospital from January 2019 to June 2021. The spinal and pelvic parameters [including pelvic tilt (PT), sacral slope (SS), PI, lumbar lordosis (LL) angle, etc.] of 409 patients with standard standing lateral radiographs before and after surgery were compared and analyzed. Postoperative follow-up of all patients with standardized SIJP assessment. The incidence of postoperative SIJP, and its correlation with sagittal parameters of the spine and pelvis, surgical methods, and the basic characteristics of patients were analyzed. The Chi-square test was used for categorical variables, the independent-sample t-test was used for generally conformed normally distributed continuous variables. Risk factors associated with the development of SIJP were analyzed using logistics regression. Correlations among SS, PI, and the 4 other sagittal parameters were analyzed using the Pearson correlation coefficient (r). Results: Postoperative PI changes tended to be larger in the lowest instrumented vertebra (LIV) (L4 and above: 1.63°; L5: 2.43°; S1: 3.83°; P<0.05) and longer fixed segment. The risk factors for SIJP included a PI >4° [odds ratio (OR) =13.051; P<0.001], LIV S1 (OR =3.378; P=0.023), and fixed total segment ≥3 (OR =2.632; P=0.038). ∆PI was significantly correlated with ∆SS in patients with non-S1 distal fixation vertebrae (R2=0.388; P<0.01), but no such correlation was found in patients with S1 distal fixation vertebrate. Conclusions: Changes in PI values after thoracolumbar spine surgery can correctly reflect the motion state of the SIJ. Excessive changes in PI (>4°) are similar to the mechanism of distal junctional kyphosis (DJK), while such changes make patients prone to SIJP following lumbar spine surgery.

Effect of 3D-CRT combined with PC chemotherapy on non-small cell lung cancer patients and serum CA125,TIMP-1,SAA levels and immune function / 国际肿瘤学杂志

Objective To investigate the effect of three-dimensional conformal radiotherapy (3D-CRT)combined with PC chemotherapy (paclitaxel + carboplatin)on non-small cell lung cancer (NSCLC) patients and the serum levels of CA125,tissue inhibitor of metalloproteinase-1 (TIMP-1),serum amyloid A (SAA)and T-lymphocyte subsets. Methods A total of 100 patients with NSCLC treated in Affiliated Hospital of Guangdong Medical University from May 2015 to December 2017 were selected as the study subjects. They were divided into control group and observation group according to random number table method,with 50 cases in each group. The observation group was treated with 3D-CRT combined with PC chemotherapy,while the con-trol group was treated with PC chemotherapy. The two groups were treated for 4 cycles. The therapeutic effect, serum CA125,TIMP-1,SAA,T-lymphocyte subsets and adverse reactions were compared between the two groups. Results Four cases were lost to follow-up both in the two groups. The overall response rate in the observation group (43. 48％,20 / 46)was higher than that in the control group (23. 91％,11 / 46;χ2 = 3. 941, P = 0. 047). The serum levels of CA125,TIMP-1 and SAA of the two groups had no significant difference be-fore treatment,and the levels of these indexes decreased after treatment. The serum levels of CA125,TIMP-1 and SAA in the observation group after treatment were (12. 31 ± 1. 13)U/ ml,(275. 31 ± 13. 69)pg/ ml and (47. 21 ± 7. 21)mg/ L,which were lower than those in the control group [(30. 36 ± 1. 98)U/ ml,(320. 36 ± 17. 23)pg/ ml,(65. 92 ± 8. 36)mg/ L],with significant differences (t = 53. 699,P < 0. 001;t = 13. 884, P < 0. 001;t = 11. 495,P < 0. 001). The levels of CD3 +,CD4 +,CD8 + and CD4 + / CD8 + of the two groups had no significant difference before treatment,and the levels of these indexes decreased after treatment. The levels of CD3 +,CD4 +,CD8 + and CD4 + / CD8 + in the observation group were (35. 27 ± 10. 31 )％, (20. 27 ± 6. 72)％,(15. 89 ± 3. 37)％ and 0. 91 ± 0. 37,which were higher than those in the control group [(30. 77 ± 9. 27)％,(15. 27 ± 5. 73)％,(12. 02 ± 2. 69)％ and 0. 75 ± 0. 39],with significant differences (t = 2. 201,P = 0. 030;t = 3. 840,P < 0. 001;t = 6. 087,P < 0. 001;t = 2. 019,P = 0. 047). There were no significant differences in the adverse reactions such as nausea and vomiting [63. 04％ (29 / 46)vs. 43. 48％(20 / 46);χ2 = 3. 537,P = 0. 060],phlebitis [6. 52％ (3 / 46)vs. 4. 35％ (2 / 46);χ2 = 0. 000,P >0. 999],abnormal liver function [6. 52％ (3 / 46)vs. 2. 17％ (1 / 46);χ2 = 0. 261,P = 0. 609]and myelo-suppression [8. 70％ (4 / 46)vs. 6. 52％ (3 / 46);χ2 = 0. 000,P > 0. 999]between the observation group and the control group. Conclusion For patients with NSCLC,3D-CRT combined with PC chemotherapy can im-prove the overall response rate,decrease the levels of serum CA125,TIMP-1 and SAA,and improve the im-mune function of patients. The therapeutic effect is remarkable and the safety is good. The therapeutic scheme is suitable for the treatment of NSCLC.

Effect of 3D-CRT combined with PC chemotherapy on non-small cell lung cancer patients and serum CA125, TIMP-1, SAA levels and immune function / 国际肿瘤学杂志

Objective@#To investigate the effect of three-dimensional conformal radiotherapy (3D-CRT) combined with PC chemotherapy (paclitaxel + carboplatin) on non-small cell lung cancer (NSCLC) patients and the serum levels of CA125, tissue inhibitor of metalloproteinase-1 (TIMP-1), serum amyloid A (SAA) and T-lymphocyte subsets.@*Methods@#A total of 100 patients with NSCLC treated in Affiliated Hospital of Guangdong Medical University from May 2015 to December 2017 were selected as the study subjects. They were divided into control group and observation group according to random number table method, with 50 cases in each group. The observation group was treated with 3D-CRT combined with PC chemotherapy, while the control group was treated with PC chemotherapy. The two groups were treated for 4 cycles. The therapeutic effect, serum CA125, TIMP-1, SAA, T-lymphocyte subsets and adverse reactions were compared between the two groups.@*Results@#Four cases were lost to follow-up both in the two groups. The overall response rate in the observation group (43.48%, 20/46) was higher than that in the control group (23.91%, 11/46; χ2=3.941, P=0.047). The serum levels of CA125, TIMP-1 and SAA of the two groups had no significant difference before treatment, and the levels of these indexes decreased after treatment. The serum levels of CA125, TIMP-1 and SAA in the observation group after treatment were (12.31±1.13) U/ml, (275.31±13.69) pg/ml and (47.21±7.21) mg/L, which were lower than those in the control group [(30.36±1.98) U/ml, (320.36±17.23) pg/ml, (65.92±8.36) mg/L], with significant differences (t=53.699, P<0.001; t=13.884, P<0.001; t=11.495, P<0.001). The levels of CD3+ , CD4+ , CD8+ and CD4+ /CD8+ of the two groups had no significant difference before treatment, and the levels of these indexes decreased after treatment. The levels of CD3+ , CD4+ , CD8+ and CD4+ /CD8+ in the observation group were (35.27±10.31)%, (20.27±6.72)%, (15.89±3.37)% and 0.91±0.37, which were higher than those in the control group [(30.77±9.27)%, (15.27±5.73)%, (12.02±2.69)% and 0.75±0.39], with significant differences (t=2.201, P=0.030; t=3.840, P<0.001; t=6.087, P<0.001; t=2.019, P=0.047). There were no significant differences in the adverse reactions such as nausea and vomiting [63.04% (29/46) vs. 43.48% (20/46); χ2=3.537, P=0.060], phlebitis [6.52% (3/46) vs. 4.35% (2/46); χ2=0.000, P>0.999], abnormal liver function [6.52% (3/46) vs. 2.17% (1/46); χ2=0.261, P=0.609] and myelosuppression [8.70% (4/46) vs. 6.52% (3/46); χ2=0.000, P>0.999] between the observation group and the control group.@*Conclusion@#For patients with NSCLC, 3D-CRT combined with PC chemotherapy can improve the overall response rate, decrease the levels of serum CA125, TIMP-1 and SAA, and improve the immune function of patients. The therapeutic effect is remarkable and the safety is good. The therapeutic scheme is suitable for the treatment of NSCLC.

En-masse retraction of maxillary anterior teeth with clear aligner: A finite element analysis / 实用口腔医学杂志

Objective:To investigate the stress distribution and the initial displacement of maxillary anterior teeth during en-masse retraction with clear aligner.Methods:The initial 3D finite element model of the maxillary teeth,PDL and alveolar bone was constructed by CBCT image reconstruction technique.Laser scanned image of crowns was merged with initial 3D model.The stress distribution and the initial displacement were analyzed by ANSYS Workbench when aligner was loaded.Results:The high simulation maxillary complex was constructed.Distal and lingual crown tipping of central incisors and lateral incisors were observed.The tendency of extrusion of the central and lateral incisors was consistant.The same tendency of stress distribution in PDL and initial displacement was appeared on incisors.The distal tipping movement was occurred on canine.Conclusion:Tipping movement along with extrusion can be produced by maxillary anterior teeth during en-rnasse retraction in extraction treatment with clear aligner.

Evaluation of the invisible bracketless appliance on maxillary molar distalization / 实用口腔医学杂志

Objective:To evaluate the clinical effects of invisible bracketless appliance on the upper molar distalization.Methods:15 patients with class Ⅱ malocclusion(at the average age of 25.3 years) were treated by invisible bracketless appliance,the pre and post three-dimensional digital models were superimposed and measured,the effects of molar distalization were analysed.Results:After treatment,the maxillary first molars were distalized by 2.58 mm on both sides.The left and fight second molars were distalized by 2.57 mm and 2.68 mm respectively.Bilateral central incisors were moved mesially by 0.34 mm.There was no significant difference in the horizontal movement of central incisor.But the left and fight first molars were moved buccally by 0.96 mm and 0.97 mm respectively,the left and fight second molars were moved buccally by 1.01 mm and 1.11 mm separately.Bilateral first molars were intruded by 0.26 mm,the left and right second molars were intruded by 0.37 mm and 0.36 mm,respectively.But the central incisors had no significant vertical movement.There was no significant difference in the buccally or palatally rotation of bilateral first and second molars.Conclusion:Invisible bracketless appliance is efficient for distalization of upper molar,but it may result in mild molar intrusion and anterior anchorage loss.

Cold ischemia-induced autophagy in rat lung tissue.

Autophagy is a highly conserved pathway that permits recycling of nutrients within the cell and is rapidly upregulated during starvation or cell stress. Autophagy has been implicated in the pathophysiological process of warm ischemia­reperfusion injury in the rat lung. Cold ischemia (CI) preservation for lung transplantation also exhibits cell stress and nutrient deprivation, however, little is known with regard to the involvement of autophagy in this process. In the present study, CI preservation­induced autophagy and apoptosis was investigated in the lungs of Sprague Dawley rats. Sprague Dawley rat lungs were flushed and preserved at 4˚C (i.e. CI) for various durations (0, 3, 6, 12 and 24 h). The levels of autophagy, autophagic cell death and apoptosis were measured at each time point following CI. The results revealed that autophagy was induced by CI preservation, which was initiated at 3 h, peaked at 6 h after CI and declined thereafter. Additionally, a coexistence of autophagic cell death and apoptosis was observed in rat lung tissues following prolonged CI. These findings demonstrate that autophagy is involved in the pathophysiological process of lung CI. Furthermore, autophagic cell death in addition to necrosis and apoptosis occurs following CI in the lung. CI preservation may therefore be a potential mechanism of lung injury during organ preservation prior to lung transplantation.

Inducible nitric oxide synthase inhibition reverses pulmonary arterial dysfunction in lung transplantation.

BACKGROUND: Ischemia-reperfusion injury (IRI) after lung transplantation remains a significant cause of morbidity and mortality. Lung IRI induces nitric oxide synthesis (iNOS) and reactive nitrogen species, decreasing nitric oxide bioavailability. We hypothesized that ischemia-induced iNOS intensifies with reperfusion and contributes to IRI-induced pulmonary arterial regulatory dysfunction, which may lead to early graft failure and cause pulmonary edema. The aim of this study was to determine whether ischemia-reperfusion alters inducible and endothelial nitric oxide synthase expression, potentially affecting pulmonary perfusion. We further evaluated the role of iNOS in post-transplantation pulmonary arterial disorder. METHODS: We randomized 32 Sprague-Dawley rats into two groups. The control group was given a sham operation whilst the experimental group received orthotropic lung transplants with a modified three-cuff technique. Changes in lung iNOS, and endothelial nitric oxide synthase expression were measured after lung transplantation by enzyme-linked immunosorbent assay (ELISA). Vasoconstriction in response to exogenous phenylephrine and vasodilation in response to exogenous acetylcholine of pulmonary arterial rings were measured in vitro as a measure of vascular dysfunction. To elucidate the roles of iNOS in regulating vascular function, an iNOS activity inhibitor (N6-(1-iminoethyl)-L-lysine, L-NIL) was used to treat isolated arterial rings. In order to test whether iNOS inhibition has a therapeutic effect, we further used L-NIL to pre-treat transplanted lungs and then measured post-transplantation arterial responses. RESULTS: Lung transplantation caused upregulation of iNOS expression. This was also accompanied by suppression of both vasoconstriction and vasodilation of arterial rings from transplanted lungs. Removal of endothelium did not interfere with the contraction of pulmonary arterial rings from transplanted lungs. In contrast, iNOS inhibition rescued the vasoconstriction response to exogenous phenylephrine of pulmonary arterial rings from transplanted lungs. In addition, lung transplantation led to suppression of PaO2/FiO2 ratio, increased intrapulmonary shunt (Q s/Q t), and increase of lung wet to dry ratio (W/D), malondialdehyde and myeloperoxidase levels, all of which were reversed upon iNOS inhibition. Furthermore, inhibition of iNOS significantly rescued vascular function and alleviated edema and inflammatory cell infiltration in the transplanted lung. CONCLUSIONS: Our data suggest that lung transplantation causes upregulation of iNOS expression, and pulmonary vascular dysfunction. iNOS inhibition reverses the post-transplantational pulmonary vascular dysfunction.

Pith decompression of the femoral head and allograft fibula grafting for treatment of avascular necrosis of femoral head / 中国骨伤

<p><b>OBJECTIVE</b>To investigate the clinical efficacy of the pith decompression of the femoral head and fibular allograft transplantation in the treatment of early stage avascular necrosis.</p><p><b>METHODS</b>From January 2004 to November 2008, 32 hips of 25 patients with avascular necrosis of femoral head of Ia-IIIb period were treated by the pith decompression of the femoral head and fibular allograft transplantation, hollow lag screw fixation, included 17 males and 8 females, aged from 20 to 55 years old (39.1 years on average). Preoperative pain was from 2 to 14 months (means 5.5 months). All patients were applied on conventional X-ray films, MRI examination, Harris score.</p><p><b>RESULTS</b>The patients were followed up for 12 to 48 months (means 36.4 months). X-ray film showed 21 hips of 18 cases improved,6 hips of 4 cases unchanged, no collapse of articular surface, 3 hips of 2 cases deterioration, 2 hips of 1 case failed. Preoperative Harris score was (77.0 +/- 8.0) and postoperative (90.6 +/- 2.5), there was a significant difference (t = 1.67, P < 0.05).</p><p><b>CONCLUSION</b>Pith decompression of the femoral head and fibular allograft transplantation in the treatment of early stage avascular necrosis of femoral head has advantage of joint function in bed-ridden after a short time, quick recovery,clinical symptoms improved. Its short-term efficacy is certain but long-term efficacy is still need further observation.</p>

Micro-modified Fulkerson osteotomy for the treatment of habituation patellar dislocation / 中国骨伤

<p><b>OBJECTIVE</b>To evaluate clinical effect of micro-modified Fulkerson osteotomy under arthroscope in treating habituation patellar dislocation.</p><p><b>METHODS</b>Twenty patients of habituation patellar dislocation (25 knees) were treated by the medial retinaculum plication, lateral retinaculum releasing and modified Fulkerson osteotomy (tibial tubercle anteromedial transfer) under arthroscope. There were 5 males and 15 females with the age from 16- to 28-years-old (average of 21 years). The subjective symptoms and the joint function were evaluated according to Lysholm and Tegner scoring system.</p><p><b>RESULTS</b>All the patients were followed up from 12 to 36 months with an average of 24 months. No found redislocation in the patients. The Lysholm score was 54.4 +/- 12.1 and 87.7 +/- 9.6 (t=2.33, P<0.05) before and after surgery respectively. The Tegner score was 2.8 +/- 0.8 and 5.1 +/- 1.3 (t=4.36, P<0.01) before and after surgery respectively.</p><p><b>CONCLUSION</b>Micro-modified Fulkerson osteotomy under arthroscope for the treatment of habituation patellar dislocation is a rescheduled in extend knee equipment, its advantages including affirmative effect, minor damage, quick rehabilitation, fewer complications and lower rate of recurrence after operation.</p>

[Effect of subchronic administered Bismerthlazol on thyroid glands of rats].

OBJECTIVE: To test the impact of subchronically administered Bismerthlazol on the thyroid morphosis of rats. METHODS: One hundred SD rats were randomly divided into one negative control group and four experimental groups with 7.0, 27.9, 111.7, and 447.0 mg/kg daily doses of Bismerthlazol, respectively. The Bismerthlazol was administered by gavage for 90 d. At the end of the experiment, the thyroids of the rats were harvested and weighted. The pathological changes of the thyroids were observed under light microscopes. The positive expression of PCNA in the thyroid glands were examined by histochemistry methods. RESULTS: Increased coefficients of thyroid gland weight were found in the experimental groups (P < 0.01). The thyroid glands showed different hyperplasia of follicular cells. Increased positive cells of PCNA were observed in the experimental groups (P < 0.05 or P < 0.01) except for the 7.0 mg/kg dose group. CONCLUSION: Long-time administered Bismerthlazol causes thyroids hyperplasia in rats. Further study on the mechanisms is warranted.