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The transition metal-catalyzed enantioselective C-H functionalization strategy has revolutionized the logic of natural product synthesis. However, previous applications have heavily relied on the use of noble metal catalysts such as rhodium and palladium. Herein, we report the efficient synthesis of C1-chiral 1,2-dihydroisoquinolines (DHIQs) via enantioselective C-H/N-H annulation of picolinamides with alkynes catalyzed by a more sustainable and cheaper 3d metal catalyst, cobalt(II) acetate tetrahydrate. A wide range of enantiomerically enriched DHIQs were obtained in good yields with excellent enantioselectivities (up to 98% yield and >99% ee). The robustness and synthetic potential of this method were demonstrated by the modular and asymmetric syntheses of several tetrahydroisoquinoline alkaloids, including (S)-norlaudanosine, (S)-laudanosine, (S)-xylopinine, (S)-sebiferine, and (S)-cryptostyline II, and the asymmetric syntheses of key intermediates of (+)-solifenacin, FR115427, and (+)-NPS R-568.
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Herein, we reported the synthesis of enantioenriched N-aryl peptoid atropisomers via Pd(II)-catalyzed atroposelective C-H olefination using the easily accessible L-pyroglutamic acid (L-pGlu-OH) as the chiral ligand. A series of optically active N-aryl peptoid atropisomers were obtained in synthetically useful yields with high enantioselectivities.
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A textile bandwidth-enhanced polarization-reconfigurable half-mode substrate-integrated cavity antenna was designed for wearable applications. A slot was cut out from the patch of a basic textile HMSIC antenna to excite two close resonances to form a wide -10 dB impedance band. The simulated axial ratio curve indicates the linear and circular polarization of the antenna radiation at different frequencies. Based on that, two sets of snap buttons were added at the radiation aperture to shift the -10 dB band. Therefore, a larger frequency range can be flexibly covered, and the polarization can be reconfigured at a fixed frequency by switching the state of snap buttons. According to the measured results on a fabricated prototype, the -10 dB impedance band of the proposed antenna can be reconfigured to cover 2.29~2.63 GHz (13.9% fractional bandwidth), and the circular/linear polarization radiation can be observed at 2.42 GHz with buttons OFF/ON. Additionally, simulations and measurements were carried out to validate the design and to study the effects of human body and bending conditions on the antenna performance.
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OBJECTIVES: To observe the protective effects of dexmedetomidine (Dex) postconditioning on myocardial ischemia/reperfusion injury (IRI) and to explore its potential molecular mechanisms. METHODS: One-hundred forty-seven male Sprague-Dawley rats were randomly divided into five groups receiving the different treatments: Sham, ischemia/reperfusion (I/R), Dex, Brusatol, Dex + Brusatol. By the in vivo rat model of myocardial IRI, cardioprotective effects of Dex postconditioning were evaluated by assessing serum CK-MB and cTnI levels, myocardial HE and Tunel staining and infarct size. Furthermore, the oxidative stress-related markers including intracellular ROS level, myocardial tissue MDA level, SOD and GSH-PX activities were determined. RESULTS: Dex postconditioning significantly alleviated myocardial IRI, decreased intracellular ROS and myocardial tissue MDA level, increased SOD and GSH-PX activities. Dex postconditioning significantly up-regulated myocardial expression of Bcl-2, down-regulated Bax and cleaved caspase-3 and decreased cardiomyocyte apoptosis rate. furthermores, Dex postconditioning promoted Nrf2 nuclear translocation, increased myocardial expression of Sirt3 and SOD2 and decreased Ac-SOD2. However, brusatol reversed cardioprotective benefits of Dex postconditioning, significantly decreased Dex-induced Nrf2 nuclear translocation and reduced myocardial expression of Sirt3 and SOD2. CONCLUSIONS: Dex postconditioning can alleviate myocardial IRI by suppressing oxidative stress and apoptosis, and these beneficial effects are at least partly mediated by activating the Nrf2/Sirt3/SOD2 signaling pathway.
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Dexmedetomidina , Daño por Reperfusión Miocárdica , Daño por Reperfusión , Sirtuina 3 , Animales , Masculino , Ratas , Apoptosis , Dexmedetomidina/uso terapéutico , Dexmedetomidina/farmacología , Daño por Reperfusión Miocárdica/tratamiento farmacológico , Daño por Reperfusión Miocárdica/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno , Transducción de Señal , Sirtuina 3/metabolismo , Sirtuina 3/farmacología , Superóxido Dismutasa/metabolismoAsunto(s)
Analgesia , Nefrolitotomía Percutánea , Anestésicos Locales , Dexametasona/uso terapéutico , Método Doble Ciego , Humanos , Nefrolitotomía Percutánea/efectos adversos , Dolor Postoperatorio/tratamiento farmacológico , Dolor Postoperatorio/etiología , Dolor Postoperatorio/prevención & control , Estudios Prospectivos , RopivacaínaRESUMEN
BACKGROUND: Sepsis, a life-threatening organ dysfunction induced by infection, is a major public health problem. This study aimed to evaluate the frequency and mortality of sepsis, severe sepsis, and septic shock in China. METHODS: We Searched MEDLINE, Embase, PubMed, and Cochrane Library from 1 January 1992 to 1 June 2020 for studies that reported on the frequency and mortality of sepsis, severe sepsis, and septic shock conducted in China. Random effects models were performed to estimate the pooled frequency and mortality of sepsis, severe sepsis, and septic shock. RESULTS: Our search yielded 846 results, of which 29 studies were included in this review. The pooled frequency of sepsis was estimated at 33.6% (95% CI 25.9% to 41.3%, I2 = 99.2%; p < 0.001), and the pooled mortality of sepsis, severe sepsis and septic shock were 29.0% (95% CI 25.3%-32.8%, I2 = 92.1%; p = 0), 31.1% (95% CI 25.3% to 36.9%, I2 = 85.8%; p < 0.001) and 37.3% (95% CI 28.6%-46.0%, I2 = 93.5%; p < 0.001). There was significant heterogeneity between studies. With a small number of included studies and the changing definition of sepsis, trends in sepsis frequency and mortality were not sufficient for analysis. Epidemiological data on sepsis in the emergency department (ED) are severely lacking, and more research is urgently needed in this area is urgently needed. CONCLUSIONS: Our findings indicated that the frequency and mortality of sepsis and septic shock in China were much higher than North America and Europe countries. Based on our results, an extremely high incidence and mortality of sepsis and septic shock in China's mainland requires more healthcare budget support. Epidemiological data on sepsis and septic shock in ED are severely lacking, and more research is urgently needed in this area. Trial registration This systematic review was conducted according to the statement of the preferred reporting items for systematic review (PROSPERO CRD42021243325) and the meta-analysis protocols (PRISMA-P).
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Sepsis , Choque Séptico , Humanos , China/epidemiología , Sepsis/epidemiología , Choque Séptico/epidemiologíaRESUMEN
BACKGROUND: Available literature indicates that long-term drinkers demand a higher dose of propofol for induction of anesthesia than non-drinkers. However, there is no study having assessed the influence of long-term high-risk drinking (LTHRD) on the effective doses of propofol for successful insertion of gastroscope with sedation. This study was designed to compare the effective doses of propofol for successful insertion of gastroscope between LTHRD and non-drinking (ND) Chinese male patients. METHODS: Thirty-one LTHRD patients and 29 ND male patients undergoing elective gastroscopy with propofol sedation were enrolled. The modified Dixon's up-and-down method was applied to determine the calculated median effective dose (ED50) of propofol for successful insertion of gastroscope. Furthermore, the isotonic regression analysis was used to establish the dose-response curve of propofol and assess the effective doses of propofol where 50% (ED50) and 95% (ED95) of gastroscope insertions were successful. RESULTS: The calculated ED50 of propofol for successful insertion of gastroscope was 1.55 ± 0.10 mg/kg and 1.44 ± 0.11 mg/kg in the LTHRD and ND patients. The isotonic regression analysis further showed that ED50 and ED95 of propofol for successful insertion of gastroscope was 1.50 mg/kg (95%CI, 1.40-1.63) and 1.80 mg/kg (95%CI, 1.74-1.90) in the LTHRD patients, respectively; 1.40 mg/kg (95% CI, 1.27-1.57) and 1.60 mg/kg (95%CI, 1.56-1.65) in the ND patients. The ED50 of propofol for successful insertion of gastroscope was not significantly different between LTHRD and ND patients. CONCLUSIONS: This study demonstrates that the difference in the estimated ED50 of propofol for successful insertion of gastroscope between LTHRD and ND Chinese male patients was not statistically significant. TRIAL REGISTRATION: The study was registered on November 28, 2020 ( ChiCTR2000040382 ) in the Chinese Clinical Trial Registry.
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Anestésicos Intravenosos , Propofol , China , Relación Dosis-Respuesta a Droga , Gastroscopios , Humanos , Intubación Intratraqueal/métodos , MasculinoRESUMEN
Objective: Myocardial ischemia/reperfusion injury (IRI) is a common and serious complication in clinical practice. Sevoflurane conditionings have been identified to provide a protection against myocardial IRI in animal experiments, but their true clinical benefits remain controversial. Here, we aimed to analyze the preclinical evidences obtained in animal models of myocardial IRI and explore the possible reasons for controversial clinical benefits. Methods: Our primary outcome was the difference in mean infarct size between the sevoflurane and control groups in animal models of myocardial IRI. After searching the databases of PubMed, Embase, Web of Science, and the Cochrane Library, a systematic review retrieved 37 eligible studies, from which 28 studies controlled comparisons of sevoflurane preconditioning (SPreC) and 40 studies controlled comparisons of sevoflurane postconditioning (SPostC) that were made in a pooled random-effects meta-analysis. In total, this analysis included data from 313 control animals and 536 animals subject to sevoflurane conditionings. Results: Pooled estimates for primary outcome demonstrated that sevoflurane could significantly reduce the infarct size after myocardial IRI whether preconditioning [weighted mean difference (WMD): -18.56, 95% CI: -23.27 to -13.85, P < 0.01; I 2 = 94.1%, P < 0.01] or postconditioning (WMD: -18.35, 95% CI: -20.88 to -15.83, P < 0.01; I 2 = 90.5%, P < 0.01) was performed. Interestingly, there was significant heterogeneity in effect size that could not be explained by any of the prespecified variables by meta-regression and stratified analysis. However, sensitivity analysis still identified the cardioprotective benefits of sevoflurane conditionings with robust results. Conclusion: Sevoflurane conditionings can significantly reduce infarct size in in-vivo models of myocardial IRI. Given the fact that there is a lack of consistency in the quality and design of included studies, more well-performed in-vivo studies with the detailed characterization of sevoflurane protocols, especially studies in larger animals regarding cardioprotection effects of sevoflurane, are still required.
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In order to reveal the dissolution behavior of iron tailings in blast furnace slag, the main component of iron tailings, SiO2, was used for research. Aiming at the problem of information loss and inaccurate extraction of tracking molten SiO2 particles in high temperature, a method based on the improved DeepLab v3+ network was proposed to track, segment, and extract small object particles in real time. First, by improving the decoding layer of the DeepLab v3+ network, construct dense ASPP (atrous spatial pyramid pooling) modules with different dilation rates to optimize feature extraction, increase the shallow convolution of the backbone network, and merge it into the upper convolution decoding part to increase detailed capture. Secondly, integrate the lightweight network MobileNet v3 to reduce network parameters, further speed up image detection, and reduce the memory usage to achieve real-time image segmentation and adapt to low-level configuration hardware. Finally, improve the expression of the loss function for the binary classification model of small object in this paper, combining the advantages of the Dice Loss binary classification segmentation and the Focal Loss balance of positive and negative samples, solving the problem of unbalanced dataset caused by the small proportion of positive samples. Experimental results show that MIoU (mean intersection over union) of the proposed model for small object segmentation is 6% higher than that of the original model, the overall MIoU is increased by 3%, and the execution time and memory consumption are only half of the original model, which can be well applied to real-time tracking and segmentation of small particles.
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Procesamiento de Imagen Asistido por Computador , Redes Neurales de la Computación , Hierro , Proyectos de Investigación , Dióxido de SilicioRESUMEN
The influence of the evolution rule of basicity (0.6â¼2.4) on the mineral composition and microstructure of sinter is studied by using a polarizing microscope, and the comprehensive application analysis of the drum index, vertical sintering speed, and yield of sinter shows that, over the course of an increase in basicity (0.6â¼1.0), the mineral structure changed from the original porphyritic-granular structure to a porphyritic structure. At the same time, there was no calcium ferrite phase in the bonding phase at a basicity of less than 1.0; therefore, the downward trend of the three indicators is obvious. When the basicity was further increased to approximately 1.6, the main structure of the mineral phase changed from a corrosion structure to an interweaving corrosion structure. Because of the existence of a porphyritic-granular structure, the structure of the mineral phase was extremely inhomogeneous and most complex near the basicity of 1.6; although a small amount of calcium ferrite displayed an acicular structure, the drum index appeared to show a very low value. With an increase in basicity to 2.0, the mineral phase structure was dominated by an interweaving corrosion structure with a uniform framework, and the content of calcium ferrite reached the highest value. Moreover, a clear acicular structure developed, and the drum index also increased to the highest value. At a basicity of more than 2.0, a mineral structure began to appear and the corrosion, porphyritic-granular structure, and the drum index also showed a slightly declining trend. Therefore, in the actual production process, basicity should be avoided as far as possible at around 1.0 and 1.6 and it should be controlled at around 2.0. At the same time, based on the mineral facies data set of this paper, the convolutional neural network is used to carry out a simple prediction model experiment on the basicity corresponding to the mineral facies photos, and the effect is quite good, which provides a new idea and method for the follow-up study of mineral facies.
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Aprendizaje Profundo , Corrosión , Estudios de SeguimientoRESUMEN
AIM: To investigate whether head and neck proprioception and motor control could be compensatory enhanced by long-term vision loss or impairment. METHODS: Individuals who were blind, low vision or sighted were included in the study, which would undergo the head repositioning test (HRT). The constant error (CE), absolute error (AE), variable error (VE) and root mean square error (RMSE) of each subject were statistically analyzed. Data were analyzed using the SAS 9.4. Tukey-Kramer for one-way ANOVA was used for comparison of blind, low vision, and sighted subjects, as well as to compare subjects with balanced vision, strong vision in the left eye and strong vision in the right eye. Independent sample t-test was used to compare subjects with congenital blindness and acquired blindness, as well as left and right hand dominance subjects. RESULTS: A total of 90 individuals (25 blind subjects, 31 low vision subjects, and 34 sighted subjects) were included in the study. Among the blind subjects, 14 cases had congenital blindness and 11 cases had acquired blindness. Among the blind and low vision subjects, 21 cases had balanced binocular vision, 17 cases had strong vision in the left eye and 18 cases had strong vision in the right eye. Among all subjects, 11 cases were left hand dominance, and 79 cases were right hand dominance. There were significant differences in AE, VE, and RMSE in head rotation between blind, low vision, and sighted subjects (P<0.01), in AE, VE, and RMSE between blind and sighted (P<0.01), and in VE and RMSE between low vision and sighted (P<0.05). No significant difference between blind and low vision (P>0.05). Significant differences in CE and AE of head right rotation and CE of general head rotation between congenital and acquired (P<0.05). No significant differences between left and right hand dominance and in balance or not of binocular vision (P>0.05). CONCLUSION: Long-term vision loss or impairment does not lead to compensatory enhancement of head and neck proprioception and motor control. Acquired experience contributes to HRT performance in the blind and has long-lasting effects on plasticity in the development of proprioception and sensorimotor control.
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BACKGROUND: The prognosis of patients with locally advanced gastric cancer with outlet obstruction is poor. Gastrectomy with curative intent is often initially impossible or difficult. OBJECTIVE: We report our experience of curative distal gastrectomy after laparoscopic gastrojejunostomy and fluorouracil, leucovorin, oxaliplatin, and docetaxel (FLOT) chemotherapy to examine the feasibility and safety of this modified strategy for locally advanced gastric cancer with outlet obstruction, initially deemed unresectable. METHODS: Between October 2017 and June 2019, 15 patients diagnosed with locally advanced gastric cancer with outlet obstruction sequentially underwent gastrojejunostomy, received four cycles of FLOT chemotherapy, and underwent laparoscopic distal gastrectomy with curative intent (R0 resection + D2 lymphadenectomy). Clinical data were retrospectively collected and analyzed. RESULTS: R0 resection was possible in 12/15 patients, laparoscopically in 11, and one conversion to laparotomy was necessary. There was no perioperative mortality in the 12 patients. Pathologic evaluation of the resected specimens revealed that complete tumor grade regression 1a (TRG1a), TRG1b, TRG2, and TRG3 occurred in 3, 2, 4, and 3 patients, respectively. CONCLUSION: This case series showed that curative surgical resection was feasible as a staged approach for patients with locally advanced gastric cancer with outlet obstruction, after initial staged gastrojejunostomy and chemotherapy.
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Obstrucción de la Salida Gástrica/cirugía , Neoplasias Gástricas/cirugía , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Quimioterapia Adyuvante , Docetaxel/administración & dosificación , Femenino , Fluorouracilo/administración & dosificación , Gastrectomía/métodos , Derivación Gástrica/métodos , Obstrucción de la Salida Gástrica/etiología , Obstrucción de la Salida Gástrica/patología , Humanos , Infusiones Intravenosas , Laparoscopía/métodos , Leucovorina/administración & dosificación , Ganglios Linfáticos/cirugía , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Epiplón/cirugía , Oxaliplatino/administración & dosificación , Estudios Retrospectivos , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/patologíaRESUMEN
Transanal total mesorectal excision (taTME) is a novel approach to radical surgery for low rectal cancer. taTME is associated with the benefits of a higher rate of free distal resection margins (DRM) under direct visualization, better visualization of the mesorectal plane, and the feasibility of overcoming the restriction of the distal pelvis. Thus, it is increasingly used globally. In this review, we investigated whether taTME yields better short- and long-term outcomes than laparoscopic TME.
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Neoplasias del Recto/cirugía , Consenso , Estudios de Factibilidad , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Cirugía Endoscópica Transanal/métodos , Cirugía Endoscópica Transanal/normasRESUMEN
BACKGROUND AND OBJECTIVES: To investigate the effects of different suture reinforcement methods for anastomotic leakage and other postoperative complications after the use of a laparoscopic double stapling technique (DST). METHODS: We collected the data of 124 patients who underwent laparoscopic radical resection of colorectal cancer from July 2017 to September 2018 at our institution. Patients were divided into three groups according to the suture reinforcement methods: intermittent, continuous suture reinforcement, and non-reinforcement (n = 41, 41, and 42, respectively). One-way analysis of variance, χ2 , Fisher's exact, and nonparametric tests were used for statistical analysis. RESULTS: Among the 124 patients, there were no statistically significant differences in operation times, intraoperative blood loss, postoperative hospital stays and recovery of bowel movement. Nine patients were diagnosed with anastomotic leakage (AL). The incidences of serious AL in the intermittent and continuous suture reinforcement groups were lower than that in the control group, with lower reoperation rate, shorter average lengths of stay and lower treatment costs of two experimental groups. CONCLUSION: Intermittent and continuous sutures after laparoscopic DST is effective, safe, and feasible on anastomotic leakage prevention. These procedures could be popularized in rectal surgery on patients with high risk of AL.
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Anastomosis Quirúrgica/métodos , Fuga Anastomótica/prevención & control , Neoplasias Colorrectales/cirugía , Anastomosis Quirúrgica/efectos adversos , Pérdida de Sangre Quirúrgica , Femenino , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Estudios RetrospectivosRESUMEN
Decreased serum thyroid hormone levels and their prediction of mortality in septic patients are still controversial, especially with the evolution of the definition of sepsis. This study aimed to assess the ability of thyroid hormone disorders to predict the early mortality of patients with septic shock defined by Sepsis-3. Sixty-three adult patients with septic shock admitted to a university hospital emergency intensive care unit (EICU) were studied. Serum free T3 (FT3), free T4 (FT4), thyroid stimulating hormone (TSH), C-reactive protein (CRP), procalcitonin (PCT), and lactate levels were determined and compared with survival status and organ dysfunction. Among the 63 patients studied, lower serum FT3 and FT4 levels were significantly associated with higher sequential organ failure assessment (SOFA) scores. Patients with septic shock with lower levels of FT3 (≤ 1.70 pmol/L) and FT4 (≤ 9.99 pmol/L) had significantly increased 28-day mortality. There was no significant difference in the serum TSH level between the survivor and nonsurvivor groups. The areas under the receiver operating characteristic curves for FT3 and FT4 levels were associated with 28-day mortality (0.92 and 0.89, respectively) and were higher than that for SOFA (0.82), CRP (0.65) and lactate (0.59). The decrease in serum levels of FT3 and FT4 in patients with septic shock is associated with the severity of organ dysfunction and 28-day mortality. Early detection of serum FT3 and FT4 levels could help clinicians to identify patients at high risk of clinical deterioration.
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Choque Séptico/sangre , Choque Séptico/mortalidad , Hormonas Tiroideas/sangre , China/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Puntuaciones en la Disfunción de Órganos , Valor Predictivo de las Pruebas , Estudios Prospectivos , Pruebas de Función de la TiroidesRESUMEN
AIM: To study the effect of an innovative micro-dissection procedure by radiofrequency ablation (MRA) in removing eyelid nevus. METHODS: Fifty-six consecutive outpatients with eyelid nevus were treated with MRA using a monopolar device. The effect of MRA was determined after following-up for 6mo to 5y. RESULTS: Fifty-two cases (52 eyes, 92.9%) were cured once, and 4 cases (4 eyes, 7.1%) received second treatment for small residual. All cases healed well after surgery, with no pigmentation, no scars, no loss of eyelashes, no deformation of eyelid margin. There was no visual impairment after healing. CONCLUSION: MRA of eyelid nevus using the XL-RFA device is highly efficient without significant complications.
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Effects of incorporation of the biochars generated from rice straw and peanut straw at different temperatures on soil pH and Pb(II) adsorption were investigated with two variable charge soils. The soil pH increased by 1.04-3.00 units, and the increase in soil pH increased with the rise of pyrolysis temperature of the biochar. Results from adsorption isotherm experiments indicated that the incorporation of the biochar enhanced the adsorption of Pb(II) by two soils. The adsorption of Pb(II) was increased by 12.6% -57.6%, when the initial concentration of Pb(II) is 2 mmol x L(-1). The adsorption also increased with rising pH. Freundlich and Langmuir equations can be used to fit the adsorption isotherms of Pb(II), but the Freundlich equation fitted the adsorption data better, the r-values are above 0.94. Soils incorporated with peanut straw char have a greater adsorption capacity for Pb(II) than these incorporated with rice straw char as predicted by the parameters of k and Q(m) in Freundlich and Langmuir equations, respectively. The biochars generated at 400 degrees C have a greater enhancement on Pb(II) adsorption by soils than 300 degrees C and 500 degrees C. Desorption results showed that the desorption of Pb(II) for the treatments with biochar added was greater than that for the control, but the amount of desorbed Pb(II) was much lower than that of adsorbed Pb(II). These results suggested that the enhanced adsorption of Pb(II) by incorporation of the biochars involved at least two mechanisms: electrostatic adsorption and non-electrostatic adsorption.