RESUMO
Tuberculosis (TB) is the leading cause of death among infectious diseases. China has a high burden of TB and accounted for almost 13% of the world's cases of multi-drug resistant (MDR) TB. Spinal TB is one reason for the resurgence of TB in China. Few large case studies of MDR spinal TB in China have been conducted. The aim of this research was to observe the epidemiological characteristics of inpatients with MDR spinal TB in six provinces and cities of China from 1999-2015. This is a multicentre retrospective observational study. Patients' information was collected from the control disease centre and infectious disease database of hospitals in six provinces and cities in China. A total of 3137 patients with spinal TB and 272 patients with MDR spinal TB were analysed. The result showed that MDR spinal TB remains a public health concern and commonly affects patients 15-30 years of age (34.19%). The most common lesions involved the thoracolumbar spine (35.66%). Local pain was the most common symptom (98.53%). Logistic analysis showed that for spinal TB patients, reside in rural district (OR 1.79), advanced in years (OR 1.92) and high education degree (OR 2.22) were independent risk factors for the development of MDR spinal TB. Women were associated with a lower risk of MDR spinal TB (OR 0.48). The most common first-line and second-line resistant drug was isoniazid (68.75%) and levofloxacin (29.04%), respectively. The use of molecular diagnosis resulted in noteworthy clinical advances, including earlier initiation of MDR spinal TB treatment, improved infection control and better clinical outcome. Chemotherapy and surgery can yield satisfactory outcomes with timely diagnosis and long-term treatment. These results enable a better understanding of the MDR spinal TB in China among the general public.
Assuntos
Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Tuberculose da Coluna Vertebral/epidemiologia , Adolescente , Adulto , Antituberculosos/uso terapêutico , China/epidemiologia , Cidades/epidemiologia , Testes Diagnósticos de Rotina/métodos , Gerenciamento Clínico , Feminino , Hospitais , Humanos , Pacientes Internados , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento , Tuberculose Resistente a Múltiplos Medicamentos/patologia , Tuberculose da Coluna Vertebral/patologia , Adulto JovemRESUMO
OBJECTIVE: The aim of the study was to investigate the impact of epidural analgesia on the stages of labor and maternal and neonatal outcomes. PATIENTS AND METHODS: A retrospective cohort study was conducted in the First Affiliated Hospital of Guangxi Medical University from January 1, 2020 to September 30, 2020. A total of 472 parturient met the inclusion criteria. Of them, 246 parturients received labor analgesia and 226 did not (control group). Their general characteristics, the length of labor, adverse reactions to analgesia, and maternal and neonatal outcomes between the two groups were compared to analyze and evaluate the feasibility of epidural analgesia in labor. RESULTS: (1) The women in the analgesia group experienced a significantly longer (p<0.001) 1st stage, 2nd stage, and total stage during labor; (2) the usage rate of oxytocin, the rate of external cephalic version, and the success rate of external cephalic version were all significantly higher in the analgesia group (p<0.001); (3) there was no statistically significant difference between the vaginal delivery rate and transit cesarean section rate of the two groups; (4) compared with the control group, the incidence of intrapartum fever was significantly increased in the analgesia group (p<0.05); (5) there was no statistically significant difference between the two groups in postpartum hemorrhage, neonatal Apgar score, and neonatal asphyxia rate. CONCLUSIONS: (1) Labor analgesia may prolong the 1st and 2nd stages of labor and increases the incidence of intrapartum fever, without increasing the rate of transit to cesarean section and postpartum hemorrhage; (2) labor analgesia does not negatively affect the Apgar score or increase the neonatal asphyxia rate.
Assuntos
Analgesia Epidural , Analgesia Obstétrica , Hemorragia Pós-Parto , Recém-Nascido , Gravidez , Feminino , Humanos , Cesárea , Analgesia Epidural/efeitos adversos , Hemorragia Pós-Parto/epidemiologia , Hemorragia Pós-Parto/etiologia , Estudos Retrospectivos , Asfixia/etiologia , China/epidemiologia , Analgesia Obstétrica/efeitos adversosRESUMO
OBJECTIVE: Osteosarcoma (OS) is one common bone malignant tumor prevailing in young adults and children. It is increasingly recognized microRNA 449a (miR 449a) as an anti-tumor factor in various tumours. However, little is known about the biological significance of miR 449a in OS. The intent of our study was to seek the prognostic values of miR-449a in OS. PATIENTS AND METHODS: Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to examine the level of miR-449a expression in 48 pairs of OS tissues and para-cancerous specimens, and the relationship between miR-449a level and clinical features of OS patient prognosis was analyzed. Moreover, we measured the miR-449a expression levels in OS cells. Transwell assay was further performed to investigate whether miR-449a influenced MG63 cell migration and invasion, which was important for malignant metastases. RESULTS: Quantitative real-time polymerase chain reaction (qRT-PCR) analysis demonstrated a notable decrease of miR-449a expressions in OS. The declined miR-449a expression was relevant with the poor prognosis and malignant clinicopathologic characteristics of OS patients. Thereafter, the functional assay was performed to determine the role of miR-449a in OS progression. Results of MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assays and transwell assays indicated that miR-449a overexpression significantly repressed OS cell proliferation, invasion, and migration. Furthermore, luciferase reporter assay showed that enhancer of zeste homolog 2 (EZH2) was a downstream target of miR-449a in OS cells. Additionally, Western blot analysis demonstrated that miR-449a exerted anti-OS functions via the regulation of phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway and epithelial-mesenchymal transition. We also indicated that miR-449a restoration could inhibit in vivo tumor growth. CONCLUSIONS: These results manifested that miR-449a may thus be used as a therapeutic target in OS treatments.
Assuntos
Neoplasias Ósseas , Proteína Potenciadora do Homólogo 2 de Zeste/genética , MicroRNAs/genética , Osteossarcoma , Neoplasias Ósseas/genética , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/mortalidade , Neoplasias Ósseas/patologia , Linhagem Celular , Movimento Celular , Proliferação de Células , Transição Epitelial-Mesenquimal , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Osteossarcoma/genética , Osteossarcoma/metabolismo , Osteossarcoma/mortalidade , Osteossarcoma/patologia , Fosfatidilinositol 3-Quinases/metabolismo , Prognóstico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de SinaisRESUMO
To evaluate the effect of bifendate on the pharmacokinetics of talinolol, 16 unrelated male healthy subjects were selected for this study. After repeated oral administration of placebo or bifendate (three times daily for 14 days), the plasma concentration of talinolol was measured by high-performance liquid chromatography-electrospray mass spectrometry. This study was carried out in a randomized, single-blinded, placebo-controlled, crossover manner. After the treatment of bifendate, the area under the curve (AUC(0-infinity)) was decreased significantly by 11.2% (90% confidence interval (CI), 7.3-12.4%; p = 0.001), and the Cmax value of talinolol was decreased by approximately 9.7% (90% CI, 5.5-11.4%; p = 0.001). The oral clearance of talinolol was increased significantly by 13.1% (90% CI, 8.0-14.4%; p = 0.001). The results suggest that the treatment of bifendate can decrease the plasma concentration of talinolol in healthy subjects.
Assuntos
Antagonistas Adrenérgicos beta/farmacocinética , Compostos de Bifenilo/farmacologia , Interações Medicamentosas , Propanolaminas/farmacocinética , Administração Oral , Adolescente , Adulto , Compostos de Bifenilo/administração & dosagem , Estudos Cross-Over , Humanos , Masculino , Método Simples-Cego , Adulto JovemRESUMO
Objective: To explore the clinical manifestation and treatment strategy for descending necrotizing mediastinitis (DNM). Methods: A total of 27 cases diagnosed as DNM from January 2010 to August 2018 in the First People's Hospital of Foshan were reviewed. There were 16 males and 11 females, age ranged from 16 to 84 years. The clinical data were collected. SPSS 16.0 software and chi square test were used for statistical analysis. Results: ALL 27 cases were diagnosed as DNM by contrast-enhanced CT scan of the neck and chest. Among the 27 cases, 13 cases resulted from peritonsillar abscess, 8 cases from esophageal foreign body perforation, 5 cases from parapharyngeal and retropharyngeal space abscess, and one case from infection of oral cavity. These 27 cases were divided into three subtypes according to the sites of mediastinitis, including 11 cases for typeâ , 5 cases for type â ¡A and 11 cases for type â ¡B. Of 27 cases, 20 cases underwent transcervical drainage for DNM, of which 5 cases with tracheotomy and 6 cases with thoracic drainage, and finally 19 of the 20 patients were cured, and one patient died of bacteremia; 7 cases refused to received surgery and were routinely treated with antibiotics, of which, one case was cured and 6 cases died. The curative rate in patients underwent surgery was significantly higher than that in patients treated with medication (χ(2)=13.638, P<0.001). Among the 20 cured cases, 4 cases were combined with diabetes mellitus and 6 cases with necrotizing fasciitis, while in the 7 died cases, 5 cases were combined with diabetes mellitus and 6 cases with necrotizing fasciitis. The comorbidity rates of diabetes mellitus (χ(2)=4.074, P=0.044) and necrotizing fasciitis (χ(2)=4.457, P=0.035) in died cases were significantly higher than those in cured cases. Conclusion: DNM is a serious infection, with high mortality especially in patients with diabetes and necrotizing fasciitis. Timely cervical and chest enhanced CT scan play vital role in its diagnosis. DNM can be treated effectively with transcervical drainage.
Assuntos
Fasciite Necrosante , Mediastinite , Abscesso Peritonsilar , Abscesso Retrofaríngeo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Drenagem , Fasciite Necrosante/diagnóstico , Fasciite Necrosante/terapia , Feminino , Humanos , Masculino , Mediastinite/diagnóstico , Mediastinite/terapia , Pessoa de Meia-Idade , Necrose , Abscesso Peritonsilar/diagnóstico , Abscesso Peritonsilar/terapia , Abscesso Retrofaríngeo/diagnóstico , Abscesso Retrofaríngeo/terapia , Adulto JovemRESUMO
OBJECTIVE: miR-300 has been demonstrated to play an important role in the progression of several tumors, but its role in tumorigenesis of laryngeal squamous cell carcinoma (LSCC) is still unclear. The purpose of this study was to explore miR-300 expression in LSCC patients and analyze its association with clinicopathological factors and prognosis. PATIENTS AND METHODS: In the present study, we measured the expression level of miR-300 in LSCC tissues by RT-PCR. Associations between miRNA-300 expressions and various clinicopathological characteristics were analyzed. Patient survival and their differences were determined by Kaplan-Meier method and log-rank test. The univariate and multivariate analysis were performed using the Cox proportional hazard analysis. RESULTS: miR-300 expression was significantly increased in LSCC tissues compared with that in adjacent non-cancerous tissues (p < 0.01). In addition, lymph node metastasis (p = 0.004) and TNM stage (p = 0.001) were obvious influence factors for the expression of miR-300. More importantly, Kaplan-Meier analysis showed that LSCC patients with low miR-300 expression tended to have shorter overall survival (p < 0.001). Finally, multivariate analysis revealed that miR-300 expression was an independent prognostic factor for LSCC patients. CONCLUSIONS: Our results pointed to miR-300 as a powerful prognostic marker in LSCC and as a novel target for tumor-suppressive therapy.
Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/metabolismo , Neoplasias Laríngeas/metabolismo , MicroRNAs/metabolismo , Idoso , Carcinoma de Células Escamosas/diagnóstico , Feminino , Humanos , Neoplasias Laríngeas/diagnóstico , Masculino , Pessoa de Meia-Idade , PrognósticoRESUMO
Objective: To study the clinical outcome of transoral CO(2) laser surgery for glottic cancer involving the anterior commissure. Methods: Thirty-two cases of glottic cancer involving the anterior commissure treated by transoral CO(2) laser surgery between March 2009 and December 2013 were retrospectively reviewed. Among these cases, 27 were T1bM0M0, 5 were T2N0M0. All cases were followed-up for more than 3 years. Results: All the 32 cases were successfully treated. Perioperative complications included injuries in the soft palate mucosa(13/32, 40.63%), loose incisors(3/32, 9.38%) and subcutaneous emphysema in the neck(2/32, 6.25%). During the follow-up period, granulation was found in all cases. Three cases had local recurrence. Two patients treated by a secondary transoral CO(2) laser surgery and the other case had total laryngectomy, all three cases were followed up for 5 years without recurrence. Two cases had regional recurrence but no primary site recurrence. One patient was treated by neck dissection, and followed up for 5 years without recurrence. The other patient died of supraclavicular and mediastinal lymph node metastasis and lung metastasis 40 months after operation. The overall 5-year survival rate was 90.6%. There was no significant difference in survival rate between T1bN0M0(92.6%) and T2N0M0(80.0%) (Log Rank χ(2)=0.788, P=0.375). The overall 5-year local regional control rate was 84.4%. In T1bN0M0 lesions, the 5-year local regional control rate was 92.6%, which was significantly higher than that in T2N0M0 lesions(40.0%) (Log Rank χ(2)=9.504, P=0.002). Conclusion: With appropriate surgical indication, detailed preoperative evaluation, good surgical skill, transoral CO(2) laser surgery may achieve satisfactory outcome in the treatment of glottic cancer involving the anterior commissure.
Assuntos
Neoplasias Laríngeas/cirurgia , Terapia a Laser/métodos , Feminino , Seguimentos , Glote/patologia , Glote/cirurgia , Humanos , Neoplasias Laríngeas/mortalidade , Neoplasias Laríngeas/patologia , Laringectomia , Terapia a Laser/efeitos adversos , Masculino , Esvaziamento Cervical , Recidiva Local de Neoplasia , Complicações Pós-Operatórias , Estudos Retrospectivos , Taxa de Sobrevida , Fatores de TempoRESUMO
OBJECTIVE: Spinal cord injury (SCI) patients had major trauma during surgery, which thus necessitates optimal choice of anesthesia drugs. The specific selection of anesthesia agents may affect body immune system. Therefore, this study aims to investigate the anesthesia effect of propofol and dexmedetomidine on the rat SCI and their effects of Th1/Th2. MATERIALS AND METHODS: Improved ALLEN's pouching method was used to generate rat SCI model. The SCI rat models were further divided into propofol and dexmedetomidine group for analyzing anesthesia time, duration, post-op analgesia time, SCI sensory function Reuter score. Real-time PCR quantified Th1 secreted cytokines interleukin (IL)-2, tumor necrosis factor (TNF)-α, Th2 secreted cytokines IL-4 and IL-10 mRNA expression levels. Enzyme labeled immunosorbent assay (ELISA) quantified serum cytokine levels. Th1 and Th2 cytokines were analyzed for correlation. RESULTS: Dexmedetomidine had shorter anesthesia onset time, longer duration time, and elongated post-op analgesia time with lower Reuter score (p<0.05 compared to propofol group). No significant difference existed between heart rate (HR), respiration rate, SpO2, and body temperature (T) during surgery. Compared to dexmedetomidine, propofol had elevated mRNA or serum levels of IL-2 and TNF-α, plus significantly lower IL-4 or IL-10 expression (p<0.05). IL-2 and TNF-α levels were negatively correlated with IL-4 and IL-10 (p<0.05). CONCLUSIONS: Dexmedetomidine had better effects for improving in-op and post-op anesthesia/analgesia effects than propofol. Both drugs can induce imbalance of Th1/Th2.
Assuntos
Anestesia , Dexmedetomidina/uso terapêutico , Propofol/uso terapêutico , Traumatismos da Medula Espinal/tratamento farmacológico , Animais , Citocinas/sangue , Ratos , Equilíbrio Th1-Th2 , Fatores de TempoRESUMO
Objective:The aim of this study was to demonstrate the risk factors which affect the exposure of glottis in suspension laryngoscopy.Method:We performed a prospective study about 90 cases of vocal cord lesions underwent microlaryngosurgery(including polyps,vocal nodules,cyst and papilloma).Then we recorded the clinical data related to glottic exposure, both preoperatively and intraoperatively. Result:Univariate analysis showed that parameters like age(P=0.038), Cormack-Lehane score(P=0.007),maximuminterincisors gap(P=0.007),hyoid-mental distance(HMD) in full extension(P=0.033), thyroid-mental distance(TMD) in full extension(P=0.014), vertical thyroid-mental distance(VTMD) in full extension(P=0.042), sternum-mental distance(SMD) in full extension(P=0.01) and degree of neck flexion-extension(P=0.003) were related to intraoperative difficult exposure of the glottic area.In logistic regression analysis, Cormack-Lehane score(P=0.003), maximuminterincisors gap(P=0.001) and degree of neck flexion-extension(P=0.002) were significantly risk factors of difficult laryngealexposure. Conclusion:Combination of Cormack-Lehane score, maximuminterincisors gap and degree of neck flexion-extensionmay help to predict the difficult laryngealexposure, so we should evaluate patients before operations of suspension laryngoscopy to decrease the surgical complication.
Assuntos
Intubação Intratraqueal/instrumentação , Doenças da Laringe/cirurgia , Laringoscopia/métodos , Laringe/cirurgia , Prega Vocal/cirurgia , Glote , Humanos , Intubação Intratraqueal/efeitos adversos , Doenças da Laringe/complicações , Doenças da Laringe/patologia , Laringoscópios , Músculos do Pescoço/patologia , Doenças Faríngeas/complicações , Doenças Faríngeas/patologia , Doenças Faríngeas/cirurgia , Estudos Prospectivos , Prega Vocal/fisiopatologiaRESUMO
OBJECTIVE: To investigate the superiority of dynamic magnetic resonance imaging as an assessment method of pharyngeal constriction and cricopharyngeal muscle function, and introduce a new way to measure the pharyngeal constriction ratio, anteroposterior diameter of esophageal entrance and thickness of cricopharyngeal muscle in healthy volunteers. METHODS: Twenty volunteers who were assessed as normal by fiberoptic endoscopic evaluation of swallowing and videofluoroscopic swallowing study were included in this study. With the use of 3.0T magnetic resonance imaging, Fiesta sequence and Asset technique, the median sagittal plane and intervertebral transverse plane from C1 to C5 were scanned repeatedly. Pharyngeal constriction ratio in the median sagittal and intervertebral transverse plane, anteroposterior diameter of esophageal entrance and thickness of cricopharyngeal muscle were assessed and the data were analysed by SPSS13.0. RESULTS: The intervertebral transverse plane between C1 and C2 was superior in observation of pharyngeal constriction ratio in the same way that the plane between C4 and C5 was superior in cricopharyngeal evaluation. The average of sagittal and intervertebral pharyngeal constriction ratio were estimated as 0.08±0.02, 0.09±0.04 respectively and the average of thickness of cricopharyngeal muscle and anteroposterior diameter of esophageal entrance were (6.50±1.69) mm, (1.99±0.76) mm respectively. CONCLUSION: Dynamic magnetic resonance imaging was superior in assessing the function of pharyngeal constriction and cricopharyngeal muscle by scanning the swallowing process in the median sagittal and intervertebral transverse plane.
Assuntos
Deglutição/fisiologia , Imageamento por Ressonância Magnética , Músculos Faríngeos/fisiologia , Faringe/fisiologia , Constrição , Voluntários Saudáveis , HumanosRESUMO
The patients with chronic superficial gastritis were selected in the study. The variation in gastric acidity output, serum gastrin and plasma somatostatin concentration were observed during the Saussurea lappa decoction (SLD) perfusion into the stomach. There was no significant changes in acidity output, serum gastrin and plasma somatostatin concentration after the perfusion of SLD (P > 0.05). Changes in gastric emptying and plasma motilin concentration were observed after oral administration of the SLD in 5 healthy volunteers. The time of gastric emptying was markedly shortened after oral administration of SLD (P < 0.01). A significant increase occurred in plasma motilin concentration at 30 min. after oral administration of SLD (P < 0.01). It revealed that SLD could accelerate the gastric emptying and increase the endogenous motilin release.
Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Esvaziamento Gástrico/efeitos dos fármacos , Gastrite/fisiopatologia , Motilina/sangue , Adulto , Feminino , Ácido Gástrico/metabolismo , Gastrinas/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Somatostatina/sangueRESUMO
OBJECTIVE: This study aimed to investigate the validity and feasibility of cervical oesophagostomy as a treatment for patients with severe dysphagia after radiotherapy for nasopharyngeal carcinoma. METHODS: The study retrospectively analysed the clinical data, symptoms, physical signs, treatment and outcomes of 12 patients treated with cervical oesophagostomy for severe dysphagia after radiotherapy for nasopharyngeal carcinoma, from 2006 to 2010. RESULTS: In all 12 cases, the oesophageal stoma remained stable, without any complications such as pharyngeal fistula or inflammation. No oesophageal stricture or granuloma growth was observed. All patients reported significant improvement in their nutritional status and quality of life after the oesophagostomy surgery. CONCLUSION: Cervical oesophagostomy is a valid and feasible method of treating severe dysphagia following radiotherapy for nasopharyngeal carcinoma. Oesophagostomy shows specific advantages over nasogastric tubing, gastrostomy and jejunostomy. Patients' nutrition and quality of life can be improved significantly if cervical oesophagostomy is executed in a timely fashion, especially in cases with severe trismus and multiple radiation-induced cranial nerve palsies unresponsive to rehabilitation.
Assuntos
Transtornos de Deglutição/cirurgia , Esofagostomia , Neoplasias Nasofaríngeas/radioterapia , Adulto , Idoso , Carcinoma , Transtornos de Deglutição/etiologia , Esofagostomia/efeitos adversos , Esofagostomia/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Estudos Retrospectivos , Resultado do TratamentoRESUMO
A variety of racemic compounds were resolved using reversed-phase thin-layer chromatography (TLC) with mobile phases containing highly concentration solutions of beta-cyclodextrin (beta-CD). These include the drugs labetalol and mephenytoin, metallocenes, crown ethers, methyl-p-toluenesulfinate, nornicotine derivaties and several dansyl and beta-naphthylamide substituted amino acids. It was possible to resolve some racemates that could not be separated on beta-CD bonded phase liquid chromatography (LC) columns with this technique. Likewise there were some compounds that could be resolved with the LC approach that failed to separate with the present TLC method. In cases of racemates that could be resolved by either approach, it was found that the retention order was exactly opposite for the two methods. Enantiomeric resolution is highly dependent on mobile phase composition. In particular, the type and amount of organic modifier as well as the concentration of beta-CD affect the observed resolution. Possible reasons for the chromatographic behavior are discussed. Several diastereoisomeric compounds were separated as well, including steroid epimers and pharmaceutical compounds.
Assuntos
Ciclodextrinas/análise , Dextrinas/análise , Preparações Farmacêuticas/isolamento & purificação , Amido/análise , Aminoácidos/análise , Cromatografia em Camada Fina , Compostos de Dansil/isolamento & purificação , Solventes , Espectrofotometria Ultravioleta , EstereoisomerismoRESUMO
Poly(dimethylsiloxane) microchip capillary electrophoresis with amperometric detection has been used for rapid separation and determination of acetaminophen and its hydrolysate, i.e. p-aminophenol. A Pt ultramicroelectrode with a diameter of 10 microm positioned at the outlet of the separation channel was used as a working electrode for amperometric detection. Factors influencing separation and detection were investigated and optimized. Results show that acetaminophen and p-aminophenol can be well separated within 35 s with RSD-1 (approximately 0.1 fmol) at S/ N=3. This method has been successfully applied to the detection of traces of p-aminophenol in paracetamol tablets.
Assuntos
Acetaminofen/análise , Aminofenóis/análise , Dimetilpolisiloxanos/química , Eletroforese Capilar/métodos , Eletroforese em Microchip/métodos , Polímeros/química , Acetaminofen/química , Eletroquímica , Eletroforese Capilar/instrumentação , Eletroforese em Microchip/instrumentação , Hidrólise , Sensibilidade e Especificidade , Fatores de TempoRESUMO
OBJECTIVE:To analysis post-treatmental reaction and long-term effect of one-visit root canal therapy by microwave instrument. METHODS:Applying heat effect and the other ones of microwave,the changes of dentine tissue of extracted teeth were observated by SEM examination.48hs and 1 year post-treatmental effect of 47 patients of periapical periodontitis treated by one-visit root canal therapy were observated and compared with the results of 54 cases treated with common method.RESULTS:In the cases of acute and chronic periapical periodontitis microwave applied in root canal therapy can close the openings of dentine,enhance the effects of sterilization and decrease times of treatment.CONCLUSION:Microwave applied in one-visit root canal therapy is competent.