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1.
Ying Yong Sheng Tai Xue Bao ; 35(1): 141-152, 2024 Jan.
Article in Chinese | MEDLINE | ID: mdl-38511450

ABSTRACT

Mixing native broadleaved tree species is a widely used method for renovating Pinus massoniana plantations. Soil microbial necromass carbon and organic carbon fractions are important parameters for evaluating the impacts of tree species mixing and soil organic carbon (SOC) stability. However, their responses to the mixing and renovation of P. massoniana plantation has not been understood yet. Here, we selected a pure P. massoniana plantation (PP) and a mixed P. massoniana and Castanopsis hystrix plantation, with ages of 16 (MP16) and 38 years (MP38), respectively, as the research objects. We quantified soil physical and chemical properties, microbial necromass carbon content, and organic carbon components at different soil layers to reveal whether and how the introduction of C. hystrix into P. massoniana plantation affected soil microbial necromass carbon and organic carbon components. The results showed that the mixed P. massoniana and C. hystrix plantation significantly reduced fungal necromass carbon content and the ratio of fungal/bacterial necromass carbon in the 0-20 cm and 20-40 cm soil layers. There were no significant differences in microbial necromass carbon contents, bacterial necromass carbon contents, and their contributions to SOC among the different plantations. The contribution of fungal necromass carbon to SOC was higher than that of bacterial necromass carbon in all plantation types. The contribution of soil mineral-associated organic carbon (MAOC) to SOC was higher than that of occluded particulate organic carbon (oPOC) and light-free particulate organic carbon (fPOC) for all plantation types. Mixing the precious broadleaved tree species (i.e., C. hystrix) with coniferous species (P. massoniana) significantly increased MAOC content and the contribution of MAOC, oPOC, and fPOC to SOC in the 0-20 cm and 20-40 cm soil layers. The MAOC of MP38 was significantly higher than that of PP in all soil layers and the MAOC of MP38 stands were significantly higher than MP16 stands in the 20-40 cm, 40-60 cm, and 60-100 cm soil layers, indicating that hybridization enhanced SOC stability and that the SOC of MP38 stands were more stable than MP16 stands. SOC and total nitrogen contents were the main environmental factors driving the changes in soil microbial necromass carbon, while soil total nitrogen and organically complexed Fe-Al oxides were the primary factors affecting organic carbon fraction. Therefore, SOC stability can be enhanced by introducing native broadleaved species, such as C. hystrix, during the management of the P. massoniana plantation.


Subject(s)
Pinus , Trees , Carbon/analysis , Soil/chemistry , Soil Microbiology , Nitrogen/analysis , Bacteria , China , Forests
2.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 26(4): 1011-1015, 2018 Aug.
Article in Chinese | MEDLINE | ID: mdl-30111399

ABSTRACT

OBJECTIVE: To explore the factors influencing total complete remission (CR), recurrence, disease-free survival (DFS) rate and overall survival (OS) rate in adults with Philadelphia (Ph) chromosome negative acute lymphoblastic leukemia (ALL) and the effect of subsequent allogeneic hematopoietic stem cell transplantation (allo-HSCT) on prognosis. METHODS: The clinical data of 87 adult patients with Ph negative ALL were retrospectively analyzed, the CHOP regimen plus L-asparaginase (L-Asp) was used for the induction therapy, and the CHOP+ modified Hyper-CVAD or methotrexate was set up as the consolidation chemotherapy regimen. After consolidation chemotherapy for 3-6 courses, 45 patients (51.72%) received allo-HSCT , and 42 patients (48.28%) continually received the maintained consolidation chemotherapy. The average follow up time of the surviving patients was 40.13 (3-60 months). RESULTS: Out of 87 patients with Ph-ALL one patient died (1.15%). In 86 patients who could be evaluated, 68 cases (79.67%) reached CR at the end of 1 course, 80 cases obtained CR (93.02%). Multivariate regression analysis showed that the enlargement of lever, spleen and lymphomode, WBC count≥ 100×109/L were affecting factors for total CR (P<0.05). Among 80 cases with CR, 27 cases (33.75%) relapsed, 5 years' overall survival (OS) rate and disease-free survival (DFS) rate were 47.50% and 45.00% respectively. Multivariate regression analysis yet showed that the induction chemotherapy without L-Asp, presence of CNS leukemia at diagnosis, absence of allo-HSCT and no CR after indution chemotherapy for 4 weeks were affecting factors for relapse and poor prognosis of patients (P<0.05). According to 4 prognostic factors such as presence of CNS leukemia or no, WBC count≥100×109/L or no, induction chemotherapy with L-Asp or no and CR after induction chemotherapy for 4 weeks or no, 86 patients were divided into low-risk group (without poor prognostic factor), middle-risk group (with 1 poor prognostic factor), high-risk group (with 2-4 poor prognostic factors). Statistical results showed that allo-HSCT treatment in low-risk group had no significant effect on OS and DFS (P>0.05). The rate of OS and DFS in middle and high-risk group were significantly higher than those of patients without allo-HSCT treatment (P<0.05). CONCLUSION: Patients with central nervous system leukemia, high white blood cell count (≥100×109/L), induction chemotherapy without L-Asp, no CR after 4 weeks of chemotherapy and absence of allo-HSCT treatment are the factors influencing the prognosis of adult patients with Ph negative ALL, so the patients with those poor prognostic factors should take active treatment of allo-HSCT.


Subject(s)
Precursor Cell Lymphoblastic Leukemia-Lymphoma , Adult , Disease-Free Survival , Hematopoietic Stem Cell Transplantation , Humans , Philadelphia Chromosome , Prognosis , Remission Induction , Retrospective Studies
3.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(6): 1519-25, 2012 Jun.
Article in Chinese | MEDLINE | ID: mdl-22870631

ABSTRACT

The degradability characteristics of film with 4 kinds of starch acetate coated and inhibitors amended urea were analyzed by FTIR, which was purposed to supply theoretical basis for applying starch acetate coated urea fertilizers in farming. The result showed that the chemical component, molecule structure and material form of the membrane were not changed because of adding different inhibitors to urea. The main peaks of the film degradation process were brought by the H--O, --OH, CO2, C==O, --CH2, --CH3, C--O, C--O--H and C--O--C vibrancy in asymmetry and symmetry. In brown soil, the trend of absorbing value of the most high peak was 0>15>30>60>90>120>150>310 d. The infrared spectra of 4 kinds of fertilizers were not different remarkably, and the film was comparatively slowly degraded before 15 d. But a majority of the film had been already degraded after 150 days. The main components of film materials were degraded fastest in 310 days. The speed of film degradation wasn't more impacted by different inhibitors. The characteristic of starch acetate film degradation may be monitored entirely and degradation speed difference of the film could be represented through infrared spectrum.

4.
Ying Yong Sheng Tai Xue Bao ; 23(10): 2663-9, 2012 Oct.
Article in Chinese | MEDLINE | ID: mdl-23359924

ABSTRACT

A laboratory incubation test with meadow brown soil was conducted to study the inhibitory effect of 3,4-dimethylpyrazole phosphate (DMPP) on soil nitrification as affected by soil moisture content (40%, 60% and 80% of the maximum field capacity), pH (4, 7 and 10), and organic matter (retained and removal). With the decrease of soil moisture content, the degradation of DMPP in soil tended to slow down, and the oxidation of soil NH4+ was more inhibited. At pH 10, more DMPP was remained in soil, and had the greatest inhibitory effect; at pH 7 and pH 4, the DMPP was lesser remained, with a smaller inhibitory effect. The removal of organic matter prolonged the remaining time of DMPP in soil, and decreased the apparent soil nitrification rate significantly.


Subject(s)
Ammonium Compounds/chemistry , Nitrification , Pyrazoles/chemistry , Soil/chemistry , Water/analysis , Computer Simulation , Ecosystem , Fertilizers , Hydrogen-Ion Concentration , Nitrates/chemistry , Organic Chemicals/chemistry
5.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 10(2): 115-8, 2002 Apr.
Article in Chinese | MEDLINE | ID: mdl-12513811

ABSTRACT

The purpose of this study was to compare the detection of trisomy 8 in myelodysplastic syndrome (MDS) patients with interphase fluorescence in situ hybridization (FISH) and cytogenetic karyotype analysis. Using Spectrum Green labeled chromosome 8 centromere probe, interphase FISH was established. The trisomy 8 clones were simultaneously detected in 48 MDS cases with FISH and conventional cytogenetic analysis (CCA). Results showed that the CCA revealed no significant difference of constitutional proportion between MDS-RA and MDS-RAEB with karyotypes of whole +8, partial +8 and one +8. With FISH, detectable rates were 66.1% for whole +8. Partial +8 and sole +8 were significantly higher than one +8 and complex +8, respectively. The percentages of trisomy 8 were similar in MDS-RA and MDS-RAEB. Trisomy 8 was detected in 1 of 15 specimens with normal or abnormal karyotype without trisomy 8 by FISH. There was linear correlation between the percentages of partial +8 detected by FISH and CCA. Two patients received CCA and FISH examination at diagnosis and during treatment, the percentage of trisomy 8 was increased with progress of disease. In conclusion, our results showed that FISH is a sensitive and accurate technique to detect trisomy 8 in MDS patients. It can provide contribute to diagnosis, assessment of curative effect and predicting progress of disease in MDS. Clone size of trisomy 8 does not related to classification of MDS, but sole +8 is seems to see in MDS-RA frequently.


Subject(s)
Chromosomes, Human, Pair 8/genetics , Myelodysplastic Syndromes/genetics , Trisomy , Humans , In Situ Hybridization, Fluorescence , Karyotyping , Myelodysplastic Syndromes/pathology , Reproducibility of Results , Sensitivity and Specificity
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