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1.
J Environ Qual ; 45(1): 331-40, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26828189

RESUMEN

The interactive effects between electron donor substances and iron (Fe) oxides have significant influence on electron transfer and the growth of Fe-reducing bacteria, which may affect the reductive dechlorination of 1,1,1-trichoro-2,2-bis(p-chlorophenyl)ethane (DDT) in soils. To evaluate the roles of volatile fatty acids and Fe(III) oxide in accelerating the reductive dechlorination of DDT in Hydragric Acrisols, a batch anaerobic incubation experiment was conducted in a slurry system with the following seven treatments: sterile soil, control (DDT-contaminated soil), lactic acid, propionic acid, goethite, lactic acid + goethite, and propionic acid + goethite. Results showed that after 20 d of incubation, DDT residues for these treatments decreased by 34, 65, 77, 81, 77, 90, and 92% of the initial quantities, respectively, with 1,1-dichloro-2,2-bis(4-chlorophenyl)-ethane as the dominant metabolite. The application of lactic acid had no significant effect on DDT dechlorination in the first 8 d while the methanogenesis rate increased quickly but accelerated DDT dechlorination after Day 8 while the methanogenesis rate decreased and Fe(II) contents increased. The application of propionic acid enhanced DDT dechlorination rates throughout the incubation. The amendment by goethite stimulated microbial reduction of Fe(III) oxides to generate Fe(II), which was an efficient electron donor, thus accelerating DDT dechlorination significantly in the early incubation period. A synergetic interaction that accelerated DDT dechlorination, either between lactic acid and goethite or between propionic acid and goethite, was obtained. The results will be of great significance to develop efficient in situ remediation technology of DDT-contaminated soil.


Asunto(s)
DDT/química , Compuestos Férricos/química , Electrones , Oxidación-Reducción
2.
Huan Jing Ke Xue ; 44(4): 1873-1881, 2023 Apr 08.
Artículo en Zh | MEDLINE | ID: mdl-37040938

RESUMEN

The dry deposition of heavy metals in atmospheric particulates is one of the important sources of heavy metals in agricultural areas, but there are few observational studies on the atmospheric deposition of heavy metals in agricultural areas. In this study, the concentrations of atmospheric particulates with different particle sizes and ten kinds of metal elements in them were analyzed by sampling a typical rice-wheat rotation area in the suburb of Nanjing for one year, and the dry deposition fluxes were estimated using the big leaf model, so as to understand the input characteristics of particulates and heavy metals. The results showed that the particulate concentrations and dry deposition fluxes were high in winter and spring but low in summer and autumn. In winter and spring, coarse particulates (2.1-9.0 µm) and fine particulates (<2.1 µm) had dual effects on particulate pollution, whereas in summer and autumn, particulate pollution was mainly attributed to the fine particulates. The concentrations of metal elements were the lowest in giant particulates (>9.0 µm) and were similar in coarse particulates and fine particulates, whereas Pb, Mn, As, and Cd elements were relatively high in fine particulates. The average annual dry deposition fluxes[g·(m2·a)-1] of particulates was giant particulates (8.31)>coarse particulates (5.99)>fine particulates (0.629). The order of average annual dry deposition fluxes[mg·(m2·a)-1] of the 10 metals was Ca(2096.4)>Al(1710.4)>Zn(855.0)>Fe(256.1)>Pb(40.35)>Cu(31.93)>V(26.21)>Mn(9.10)>As(2.48)>Cd(0.28). The average annual dry deposition fluxes of the 10 metal elements in fine particulates, coarse particulates, and giant particulates were 179.03, 2124.97, and 2724.18 mg·(m2·a)-1, respectively. These results will provide a reference for a more comprehensive understanding of the impact of human activities on the quality and safety of agricultural products and soil ecological environment.

3.
Environ Monit Assess ; 167(1-4): 105-13, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19557535

RESUMEN

Atmospheric dry deposition is an important nitrogen (N) input to farmland ecosystems. The main nitrogen compounds in the atmosphere include gaseous N (NH3, NO2, HNO3) and aerosol N (NH4+/NO3-). With the knowledge of increasing agricultural effects by dry deposition of nitrogen, researchers have paid great attention to this topic. Based on the big-leaf resistance dry deposition model, dry N deposition velocities (Vd) in a typical red soil agro-ecosystem, Yingtan, Jiangxi, Southeastern China, were estimated with the data from an Auto-Meteorological Experiment Station during 2004-2007. The results show that hourly deposition velocities (Vdh) were in the range of 0.17-0.34, 0.05-0.24, 0.57-1.27, and 0.05-0.41 cm/s for NH3, NO2, HNO3, and aerosol N, respectively, and the Vdh were much higher in daytime than in nighttime and had a peak value around noon. Monthly dry deposition velocities (Vdm) were in the range of 0.14-0.36, 0.06-0.18, and 0.07-0.25 cm/s for NH3, NO2, and aerosol N, respectively. Their minimum values appeared from June to August, while their maximum values occurred from February to March each year. The maximum value for HNO3 deposition velocities appeared in July each year, and Vdm(HNO3) ranged from 0.58 to 1.31 cm/s during the 4 years. As for seasonal deposition velocities (Vds), Vds(NH3), Vds(NO2), and Vds(aerosol N) in winter or spring were significantly higher than those in summer or autumn, while Vds(HNO3) in summer were higher than that in winter. In addition, there is no significant difference among all the annual means for deposition velocities (Vda). The average values for NH3, NO2, HNO3, and aerosol N deposition velocities in the 4 years were 0.26, 0.12, 0.81, and 0.16 cm/s, respectively. The model is convenient and feasible to estimate dry deposition velocity of atmospheric nitrogen in the typical red soil agro-ecosystem.


Asunto(s)
Aire/análisis , Ecosistema , Monitoreo del Ambiente , Nitrógeno/análisis , Suelo/análisis , Atmósfera , China
4.
Zhonghua Nei Ke Za Zhi ; 48(9): 737-40, 2009 Sep.
Artículo en Zh | MEDLINE | ID: mdl-20079209

RESUMEN

OBJECTIVE: To explore the value of conventional cytogenetic technique (CC), modified cell culture (long term culture and increasing the final concentration of colcemid) and fluorescence in situ hybridization (FISH) in detection of chromosomal and genomic aberrations of multiple myeloma(MM). METHODS: RHG banding was used to evaluate the efficiency of modified culture method on abnormal karyotype detection in 21 MM patients. The probes 1q21, 13q14 (RB1), 14q32 (IGHC/IGHV gene) were used to perform FISH in the detection of chromosomal and genomic aberrations of MM. RESULTS: Abnormal chromosomes were detected in 4 cases (19.1%) of the 21 MM patients with CC. After modified cell culture, abnormal karyotype was detected in 6 cases (28.6%). Abnormal chromosomes were detected in 12 of 18 cases (66.7%) using FISH. Panel FISH disclosed 1q21 amplification in 4 (22.2%), del(13q) abnormality in 5 (27.8%), 14q32 rearrangement in 8 (44.4%). CONCLUSION: FISH can significantly improve the detection rate of chromosomal aberrations in MM.


Asunto(s)
Citogenética/métodos , Mieloma Múltiple/genética , Anciano , Aberraciones Cromosómicas , Femenino , Humanos , Hibridación Fluorescente in Situ , Masculino , Persona de Mediana Edad , Células Tumorales Cultivadas
5.
Environ Monit Assess ; 159(1-4): 241-53, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18998222

RESUMEN

A 2-year monitoring study was conducted to estimate nitrogen deposition to a typical red soil forestland in southeastern China. The dry deposition velocities (V(d)) were estimated using big leaf resistance analogy model. Atmospheric nitrogen dry deposition was estimated by combing V(d) and nitrogen compounds concentrations, and the wet deposition was calculated via rainfall and nitrogen concentrations in rainwater. The total inorganic nitrogen deposition was 83.7 kg ha(-1) a(-1) in 2004 and 81.3 kg ha(-1) a(-1) in 2005, respectively. The dry deposition contributed 78.6% to total nitrogen deposition, in which ammonia was the predominant contributor that accounted for 86.1%. Reduced nitrogen compounds were the predominant contributors, accounting for 78.3% of total nitrogen deposition. The results suggested that atmospheric inorganic nitrogen could be attributed to intensive agricultural practices such as excessive nitrogen fertilization and livestock production. Therefore, impacts of atmospheric nitrogen originated from agriculture practices on nearby forest ecosystems should be evaluated.


Asunto(s)
Monitoreo del Ambiente , Nitrógeno/análisis , Suelo/análisis , Árboles , China , Nitrógeno/química , Compuestos de Nitrógeno/análisis , Compuestos de Nitrógeno/química
6.
J Appl Biomater Funct Mater ; 14 Suppl 1: e15-9, 2016 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-27339281

RESUMEN

This paper establishes a density gradient model along the thickness direction of a circular plate made of foamed material. Based on the first shear deformation plate theory, the result is deduced that the foamed metal circular plate with graded density along thickness direction yields axisymmetric bending problem under the action of uniformly distributed load, and the analytical solution is obtained by solving the governing equation directly. The analyses on two constraint conditions of edge radial clamping and simply supported show that the density gradient index and external load may affect the axisymmetric bending behavior of the plate. Then, based on the classical plate theory, the paper analyzes the behavior of axisymmetric buckling under radial pressure applied on the circular plate. Shooting method is used to obtain the critical load, and the effects of gradient nature of material properties and boundary conditions on the critical load of the plate are analyzed.


Asunto(s)
Metales , Modelos Teóricos , Estrés Mecánico
7.
Huan Jing Ke Xue ; 35(3): 1164-8, 2014 Mar.
Artículo en Zh | MEDLINE | ID: mdl-24881412

RESUMEN

A pot experiment was conducted to study the effects of UV-B radiation enhancement alone, 1,2,4-trichlorobenzene (TCB) contamination soil alone, and the combined stress on the growing process, stomatal resistance and leaf structure of green vegetable. The results showed that 1,2,4-TCB contamination alone had more significant inhibitory effect on the growth of green vegetable than the combined stress. Both UV-B radiation enhancement and 1,2,4-TCB contamination reduced the stomatal resistance of front and reverse leaves. Enhanced UV-B radiation resulted in the albino of leaves. 1,2,4-TCB contamination resulted in the fading of leaf color and the appearing of black spots on leaf surfaces, and the enhanced UV-B radiation strengthened the black-spot symptom. In conclusion, the effects of UV-B radiation enhancement alone, 1,2,4-trichlorobenzene (TCB) contamination soil alone and the combined stress on the growth indicators of green vegetable were different.


Asunto(s)
Clorobencenos/química , Rayos Ultravioleta , Verduras/efectos de los fármacos , Verduras/efectos de la radiación , Contaminantes del Suelo/química
8.
Zhonghua Xue Ye Xue Za Zhi ; 34(4): 313-6, 2013 Apr.
Artículo en Zh | MEDLINE | ID: mdl-23668203

RESUMEN

OBJECTIVE: To evaluate the efficacy and safety of dose-reduced intravenous busulfan, cyclophosphamide and etoposide (BCV) as conditioning for autologous stem cell transplantation (ASCT) in multiple myeloma (MM). METHODS: From September 2007 to September 2010, thirty-two ASCT-eligible patients with MM received high dose melphalan (HDM) as conditioning in our center. Median age was 53.5 (30-63) years. From October 2010 to October 2012, thirty-eight patients conditioned by BCV regimen (intravenous busulfan, total doses 9.6 mg/kg), whose median age was 54(35-64) years. RESULTS: There were no statistical differences in clinical characteristics between the two groups, including myeloma isotype, Durie-Salmon staging, international staging system(ISS), and patients received the first line, second line or more than third line therapy. The median time to neutrophil and platelet engraftment were 10.5 vs 11 days (P=0.057) and 11 vs 12 days (P=0.100) in the BCV and HDM groups, respectively. The toxicity of two conditioning regimens had no significant difference. None of hepatic veno-occlusive disease and early transplant related mortality was observed. Although overall response rates showed no significant difference between two groups (P>0.05), the CR rates increased from 44.74% pre-ASCT to 63.18% post-ASCT in the BCV group, while 37.50% to 59.38% in the HDM group. During the median follow-up of 16 months (range 2-27) in BCV group, ten patients (26.32%) developed progressive disease and PFS at 12 months were 71.37%. CONCLUSIONS: In this study, the dose-reduced intravenous busulfan, cyclophosphamide and etoposide (BCV) conditioning was demonstrated an effective and safety regimen for ASCT-eligible patients with MM. However, the long term observation is needed.


Asunto(s)
Busulfano/uso terapéutico , Ciclofosfamida/uso terapéutico , Etopósido/uso terapéutico , Trasplante de Células Madre Hematopoyéticas , Mieloma Múltiple/terapia , Acondicionamiento Pretrasplante , Adulto , Femenino , Estudios de Seguimiento , Humanos , Masculino , Melfalán/uso terapéutico , Persona de Mediana Edad , Trasplante Autólogo , Resultado del Tratamiento
9.
Zhonghua Xue Ye Xue Za Zhi ; 34(4): 341-4, 2013 Apr.
Artículo en Zh | MEDLINE | ID: mdl-23668209

RESUMEN

OBJECTIVE: To improve the understanding of the clinical and laboratory features of the IgM multiple myeloma (MM). METHODS: The clinical data of four cases of IgM MM patients were collected, their clinical and laboratory features were summarized and analyzed. RESULTS: Four patients met the criteria of IgM MM. They were all male. The age at the diagnosis ranged from 54 to 69 years. The primary symptoms included bone pain, hyperviscosity and bleeding. Three cases had κ-chain and only one case had λ-chain. They were all staged ⅢA according to the Durie-Salmon staging system (DSS). One case stagedⅠand three cases staged Ⅱ according to the international staging system (ISS). The average value of IgM, hemoglobin, serum calcium, creatinine and the proportion of bone marrow plasma cells were 83.6 (52.9-111.0) g/L, 79.5 (61.0-105.0) g/L, 3.20(2.11-6.00) mmol/L, 104.3 (56.0-171.0) µmol/L and 0.558 (0.290-0.775), respectively. Bone destruction was found in 3 cases. Immunophenotypes of bone marrow plasma cells were analyzed in 3 patients. Results showed that these cells expressed CD38 and CD138, and did not express CD19, CD20 and CD117. Chromosome and fluorescence in situ hybridization (FISH) analysis were carried out in 4 cases and found that all of them had IgH translocations and 1q21 amplification, 2 cases had 13q and 17p deletion, and 3 cases had t(11;14). Three patients received bortezomib-based regimens as induction therapy and reached partial response (PR) - very good partial response (VGPR). Followed up to November 30, 2012, the median progress-free survival (PFS) and overall survival (OS) of the 4 cases were only 6.0 (2.5-7.0) months and 17.5 (2.5-27.0) months, respectively. CONCLUSIONS: IgM MM is very rare and is no more than 0.5% in all types of MM. IgM MM have frequent t(11;14) and amp(1q21). Bortezomib-based regimens are effective for it, however, the disease progresses rapidly and has poor prognosis.


Asunto(s)
Mieloma Múltiple , Anciano , Humanos , Inmunoglobulina M/genética , Masculino , Persona de Mediana Edad , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/genética , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos , Translocación Genética
10.
Zhonghua Xue Ye Xue Za Zhi ; 34(4): 309-12, 2013 Apr.
Artículo en Zh | MEDLINE | ID: mdl-23668202

RESUMEN

OBJECTIVE: To evaluate the efficacy and safety of bortezomib retreatment in 76 patients with relapsed/refractory multiple myeloma (MM), who previously responded to bortezomib. METHODS: Retrospective analysis of 76 MM patients, who had achieved at least a partial response (PR) on initial bortezomib therapy in our hospital from May 2006 to August 2011, received bortezomib retreatment when they relapsed or progressed. RESULTS: The overall response rate (ORR) was 60.5%, among them 6.5% patients achieved CR, 5.8% patients achieved very good partial response (VGPR), 38.2% patients achieved PR. Then we further stratified all patients into 3 groups according to the response of initial bortezomib therapy, including CR group, VGPR group and PR group. After bortezomib retreatment, the ORR of the 3 groups was 84.6%, 73.1% and 43.2%, respectively. According to the response of bortezomib retreatment, the patients were divided into 2 groups: group 1 who at least achieved PR, group 2 who showed no response. The median progression-free survival (PFS) after bortezomib retreatment for group 1 and 2 was 7(1-39) and 5(1-14) months, respectively (P>0.05), while the median overall survival (OS) after bortezomib retreatment was 16(2-64) and 8(1-28) months, respectively (P<0.05). Adverse events (AE) were identified in 88% patients during bortezomib retreatment, including neutropenia, diarrhea and thrombocytopenia, only 9.2%(7 patients) reached Ⅲ-Ⅳ grade of AE. Severe peripheral neuropathy occurred in only one patient. CONCLUSION: Bortezomib retreatment regimen is demonstrated a higher response rate in patients who achieved deeper response in initial treatment, with no more adverse events.


Asunto(s)
Ácidos Borónicos/uso terapéutico , Mieloma Múltiple/tratamiento farmacológico , Pirazinas/uso terapéutico , Adulto , Anciano , Ácidos Borónicos/efectos adversos , Bortezomib , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pirazinas/efectos adversos , Estudios Retrospectivos , Resultado del Tratamiento
11.
Environ Pollut ; 158(2): 409-15, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19781829

RESUMEN

Human activities have resulted in cadmium (Cd) and sulfur (S) accumulation in paddy soils in parts of southern China. A combined soil-sand pot experiment was conducted to investigate the influence of excessive S supply on iron plaque formation and Cd accumulation in rice plants, using two Cd levels (0, 1.5 mg kg(-1)) combined with three S concentrations (0, 60, 120 mg kg(-1)). The results showed that excessive S supply significantly decreased Cd accumulation in brown rice due to the decrease of Cd availability and the increase of glutathione in rice leaves. But excessive S supply obviously increased Cd accumulation in roots due to the decrease of iron plaque formation on the root surface of rice. Therefore, excessive S supply may result in loss of rice yield, but it could effectively reduce Cd accumulation in brown rice exposed to Cd contaminated soils.


Asunto(s)
Cadmio/farmacocinética , Oryza/metabolismo , Contaminantes del Suelo/farmacocinética , Azufre/metabolismo , Análisis de Varianza , Cadmio/metabolismo , China , Glutatión/análisis , Oryza/crecimiento & desarrollo , Hojas de la Planta/química , Contaminantes del Suelo/metabolismo , Espectrofotometría Atómica
12.
Zhonghua Zheng Xing Wai Ke Za Zhi ; 20(5): 361-3, 2004 Sep.
Artículo en Zh | MEDLINE | ID: mdl-15623107

RESUMEN

OBJECTIVE: To investigate the clinical effect of improved laparoscopic Vechitti procedure for constructing a functioning vagina. METHODS: By using the method of raising vestibular mucosa, 18 patients with congenital absence of vagina and uterus underwent surgery in our hospital. No cave was made between bladder and rectum. The procedure involved puncturing the vulvar vestibulum pit with an epidural paracentetic needle or specially-made needle into abdominal cavity through rectovesical interspace, two drag-lines was introduced through anterior abdominal wall, using the line to tie a clothes button of 2.0-2.5 cm diameter to the vulva, rasing the lines day by day, the vestibule go upward along with the button, then the vagina was formed. RESULTS: After the procedures, the artificial vagina of all 18 patients could hold a speculum and the mucosa appeared soft and smooth with normal lubrication. The vulvar tissues appeared uninjured and normal in all cases. The married patients were satisfactory to the intercourse. One case of vagino-rectal fistula was observed in a patient after she rode a bicycle with the vaginal mould. CONCLUSION: The improved laparoscopic Vechitti procedure for constructing a functioning vagina has less trauma than conventional operation and is easy to operate. Therefore, the new improved procedure is a preferred way in constructing vagina for treating those patients.


Asunto(s)
Procedimientos Quirúrgicos Ginecológicos/métodos , Laparoscopía/métodos , Vagina/cirugía , Adulto , Femenino , Procedimientos Quirúrgicos Ginecológicos/efectos adversos , Humanos , Satisfacción del Paciente , Resultado del Tratamiento , Vagina/anomalías
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