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1.
Echocardiography ; 36(2): 257-265, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30561121

RESUMO

BACKGROUND: The myocardial structure differs between secondary left ventricular hypertrophy (LVH) and hypertrophic cardiomyopathy (HCM). We investigated left ventricular function of these two types of hypertrophy using multilayer strain analysis with two-dimensional echocardiography. METHODS: Transthoracic echocardiography (Vivid-E9) was performed in 240 patients with preserved left ventricular ejection fraction (LVEF ≥50%) and with either HCM (n = 80, 63 men, age 49.8 ± 14.1 years), hypertensive LVH (n = 80, 63 men, age 51.4 ± 13.3 years) or normal blood pressure and left ventricular structure (n = 80, 63 men, 50.8 ± 12.4 years). Quantitative multilayer longitudinal strain (LS), circumferential strain (CS), and radial strain (RS) were analyzed. The ratio of endo-/epi-myocardial strain was calculated. RESULTS: Longitudinal strain was significantly (P < 0.001) lower in HCM patients than normal controls (15.2 ± 4.2% vs 23.1 ± 2.7%), especially in hypertrophic segments (14.5 ± 4.4% vs 17.2 ± 3.2% in nonhypertrophic segments, P < 0.01). LS was lower in patients with hypertensive LVH, similarly in all left ventricular segments (20.7 ± 3.7%, P < 0.001 vs controls). CS was lower in the mid- and epicardium (P < 0.01), but not endocardium in HCM (P = 0.4), and preserved in all myocardial layers in hypertensive LVH. The endo-/epi-myocardial ratios of both LS and CS were higher in HCM than hypertensive LVH (P < 0.01). RS was higher (P < 0.01) in HCM than hypertensive LVH and controls. Endocardial CS and global RS were correlated with LVEF (r ≥ 0.32, P < 0.01). CONCLUSIONS: Hypertrophic cardiomyopathy patients had marked reductions in LS and CS, whereas patients with hypertensive LVH had less reduction in LS and preserved CS. The increased endo-/epi-myocardial ratios of LS and CS may be useful in differentiating HCM from hypertensive LVH.


Assuntos
Cardiomiopatia Hipertrófica/diagnóstico por imagem , Cardiomiopatia Hipertrófica/fisiopatologia , Ecocardiografia/métodos , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Hipertrofia Ventricular Esquerda/fisiopatologia , Feminino , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/fisiopatologia , Humanos , Hipertrofia Ventricular Esquerda/patologia , Masculino , Pessoa de Meia-Idade
2.
J Nanosci Nanotechnol ; 17(1): 681-89, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29630815

RESUMO

Pectin, a natural plant polysaccharide, holds great potential for biomedicine. Developing low molecular weight (Mw) pectin-based nanofibers is desirable for biomedical applications in which fast degradation and elimination of polymer from the body are required. Here, we report the first work on fabricating low Mw pectin-based nanofibers through electrospinning, among which the content of carrier polymer, poly(ethylene oxide) (PEO), can be minimized to 10%. Surfactant (Triton X-100), high polymer concentration and cosolvent were essential to electrospin bead-free nanofibers at low PEO content. The size of pectin nanofibers was dependent on polymer concentration and cosolvent. The presence of cosolvent inhibited the crystallization of PEO, but enhanced the crystallization of pectin. Meanwhile, glycerol as cosolvent could lead to phase separation of polymers. This work provides a new prospective for the fabrication of low Mw pectin nanofibers suitable for in vivo applications with the demand of fast degradation.

3.
Tumour Biol ; 36(7): 5515-22, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25724182

RESUMO

Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) is widely used in preoperative diagnosis of various tumors. We investigated the clinical value of DCE-MRI in differential diagnosis of malignant and benign ovarian lesions. The study involved 48 subjects with surgical pathology-confirmed ovarian tumors with solid components. Early dynamic phase enhancement performances of the ovarian lesions in patients were assessed, including the enhancement pattern, time-signal intensity curve (TIC), signal intensity rate at the initial 60 s (SI60), time to peak within 200 s (TTP200), and slope ratio. There were significant differences in enhancement patterns between benign and malignant ovarian tumors (P < .05). A total of 30 malignant tumors (30/31) displayed type I TIC, 8 benign tumors (8/13) showed type III TIC, and significant differences were found in TIC type between malignant and benign ovarian lesions (P < 0.01). Benign ovarian tumors showed lower SI60 (%) and slope ratio, as well as significantly prolonged TTP20, compared to malignant ovarian tumors (all P < 0.01). The microvessel count (MVC) of malignant tumors was significantly higher than that of benign tumors (P < 0.05). Receiver operating characteristic (ROC) curve analyses revealed that DCE-MRI provided an optimal diagnostic performance with threshold values of SI60 at 83.40 %, TTP200 at 77.65 s, and slope ratio at 4.12. These findings revealed that DCE-MRI provides critical information required for differential diagnosis of malignant and benign ovarian lesions.


Assuntos
Diagnóstico Diferencial , Imageamento por Ressonância Magnética/métodos , Neoplasias Ovarianas/diagnóstico por imagem , Teratoma/diagnóstico por imagem , Adolescente , Adulto , Idoso , Criança , Meios de Contraste , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Pessoa de Meia-Idade , Neoplasias Ovarianas/patologia , Radiografia , Teratoma/patologia
4.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 28(3): 287-92, 2011 Jun.
Artigo em Zh | MEDLINE | ID: mdl-21644225

RESUMO

OBJECTIVE: To investigate the association between the genetic variations of the functional region in bone morphogenetic protein gene (BMP7) with type 2 diabetes mellitus in Chinese Uygur individuals. METHODS: A case-control study was conducted based on epidemiological investigation. A total of 717 Uygur subjects (276 males and 441 females) were selected and divided into two groups: diabetes mellitus group (n = 502, 191 males and 311 females) and control group (n = 215, 85 males and 130 females). All exons, flanking introns and the promoter regions of (BMP7) gene were sequenced in 48 Uygur diabetics. Representative variations were selected according to the minor allele frequency (MAF) and linkage disequilibrium and genotyped using the TaqMan polymerase chain reaction method in 717 Uygur individuals, a relatively isolated general population in a relatively homogeneous environment and a case-control study was conducted to test the association between the genetic variations of (BMP7) gene and type 2 diabetes mellitus. RESULTS: Five novel and 8 known variations in the (BMP7) gene were identified. All genotype distributions were tested for deviations from Hardy-Weinberg equilibrium (P> 0.05). There was significant difference of genotype distribution of rs6025422 between type 2 diabetes mellitus and control groups in the male population (P< 0.05, P adjusted > 0.05), but there was no difference in total and female population (P> 0.05). And the means of fasting blood glucose (FBG), fasting insulin and HOMA-index significantly decreased in individuals with AA, AG and GG genotypes of rs6025422 in male population (P< 0.05), but not in total and female population (P> 0.05). The logistic regression analysis showed that GG genotype of rs6025422 variation might be a protective factor for diabetes in male (OR= 0.637, 95% confidence interval 0.439-0.923, P< 0.05). CONCLUSION: The present study suggests that the rs6025422 polymorphism in (BMP7) gene may be associated with diabetes mellitus and insulin resistance in Uygur men.


Assuntos
Proteína Morfogenética Óssea 7/genética , Diabetes Mellitus Tipo 2/genética , Variação Genética , Resistência à Insulina/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , China , Feminino , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Humanos , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Fenótipo
5.
Artigo em Zh | MEDLINE | ID: mdl-21619797

RESUMO

OBJECTIVE: To investigate the expression of nuclear factor kappa B (NF-kgr;B) and tumor necrosis factor α (TNF-α) in lung tissue of acute paraquat poisoned rats. METHODS: 68 male Wistar rats were randomly divided into 2 groups: the control group (n = 8), the intoxication group (n = 60). On the 1st, the 3rd, the 7th, the 14th and the 28th day after intoxication, the expression of NF-κB p65 and TNF-α in lung tissue were detected by LSAB immunohistochemistry (IH) staining. Meanwhile, the level of malondialdehyde (MDA) in plasma, and lung homogenate, the content of malondialdehyde (HPY) in lung homogenate were detected. RESULTS: The levels of MDA in plasma on the 1st, the 3rd, the 7th day and in lung homogenate on the 1st, the 3rd day of the intoxication group [in plasma: (10.15 ± 3.15), (6.97 ± 1.65) and (5.44 ± 0.66) nmol/ml; in lung homogenate: (10.20 ± 2.43), (10.71 ± 171) nmol/ml] were significantly higher than that of the control group [in plasma: (3.84 ± 1.04) nmol/ml, in lung homogenate: (7.66 ± 0.66) nmol/ml]. The content of HPY in lung homogenate on the 14th and the 28th day after intoxication [(19.98 ± 2.86), (26.06 ± 4.06) µg/0.1 g lung homogenate] were higher than that of the control group [(8.80 ± 1.26) µg/0.1 g lung homogenate] significantly. The expression of NF-κB p65 and TNF-α in lung tissue were both significantly increased on the first day and the 3rd day of the intoxication group compared with the control group and weakened obviously after the 7th day. CONCLUSION: Acute paraquat poisoning can induce increased expression of both NF-κB p65 and TNF-α in lung tissue; the enhanced activity of NF-κB may take part in the process of pulmonary injury in PQ poisoning.


Assuntos
Paraquat/intoxicação , Fator de Transcrição RelA/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Animais , Pulmão/metabolismo , Pulmão/patologia , Masculino , Ratos , Ratos Wistar
6.
Int J Gen Med ; 14: 7729-7740, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34785931

RESUMO

PURPOSE: The metabolic score for insulin resistance (METS-IR) index is an emerging surrogate predictor of type 2 diabetes mellitus (T2DM). This study aimed to evaluate the association between the METS-IR index and the risk of T2DM in non-obese Japanese adults. METHODS: A total of 12,290 non-obese participants were selected from the NAGALA prospective cohort study conducted from 2004 to 2015. Cox proportional hazards models were used to assess the association between the baseline METS-IR index and risk of T2DM. Generalized additive models were used to identify nonlinear relationships. In addition, we performed subgroup analyses and interaction tests. Results were expressed as hazard ratios (HRs) and 95% confidence intervals (CIs). RESULTS: During a median follow-up of 2050 days, 176 (1.43%) incident T2DM occurred. The fully adjusted HR (95% CI) for the incidence of T2DM in non-obese adults was 1.17 (HR=1.17, 95% CI: 1.09-1.27, P<0.001) for every 1-unit increase in the METS-IR index. The risk of developing T2DM increased with the quartile of change in the METS-IR index, after adjustment for multiple potential confounding, the HRs for the Q4 group versus the Q1 group was 4.01 (95% CI, 1.39-11.57). Generalized additive models also showed a cumulative increase in the risk of T2DM with increasing the METS-IR index. Time-dependent receiver operating curve suggested helpful discriminative power of the METS-IR index for T2DM. The C-statistics by the clinical risk factors significantly improve with the addition of the METS-IR index (from 0.862 to 0.875, P = 0.035); the discriminatory power and risk reclassification also appeared to be substantially better, with the category-free NRI of 0.216, and the IDI of 0.011. CONCLUSION: The METS-IR index was a significant and independent predictor for future T2DM development in non-obese adults. The METS-IR index may have clinical significance in identifying groups at high risk of T2DM.

7.
Open Med (Wars) ; 16(1): 1718-1727, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34825063

RESUMO

Mitophagy affects the activation of hepatic stellate cells (HSCs). Mitochondria-targeted ubiquinone (MitoQ) is a mitochondria-targeted antioxidant that reduces the production of intracellular reactive oxygen species (ROS). However, its relationship with mitophagy remains unclear. This study evaluated mitophagy during HSC activation and the effects of MitoQ on mitophagy in cell culture and in an animal model of the activation of HSCs. We found that MitoQ reduced the activation of HSCs and alleviated hepatic fibrosis. PINK1 (PTEN-induced putative kinase 1) is a putative serine/threonine kinase located in the mitochondria's outer membrane. While the activation of primary HSCs or LX-2 cells was associated with reduced PINK1/parkin-mediated mitophagy, MitoQ reduced intracellular ROS levels, enhanced PINK1/parkin-mediated mitophagy, and inhibited the activation of HSCs. After knocking down the key mitophagy-related protein, PINK1, in LX-2 cells to block mitophagy, MitoQ intervention failed to inhibit HSC activation. Our results showed that MitoQ inhibited the activation of HSCs and alleviated hepatic fibrosis by enhancing PINK1/parkin-mediated mitophagy.

8.
Zhonghua Xin Xue Guan Bing Za Zhi ; 38(10): 939-42, 2010 Oct.
Artigo em Zh | MEDLINE | ID: mdl-21176641

RESUMO

OBJECTIVE: To analyze etiology of hospitalized hypertensive patients in the department of hypertension from 1999 to 2008. METHODS: This retrospective study was performed to analyze the etiology of hospitalized hypertensive patients in department of hypertension and to show the distribution change of hypertension from 1999 to 2008. RESULTS: (1) There were 5867 (75.1%) patients with essential hypertension and 1942 (24.9%) patients with secondary hypertension (SH). (2) The prevalence rate of SH increased significantly during the 10 years (χ(2) = 387.621, P < 0.001) and was higher in 2008 than in 1999 (39.3% vs. 9.5%, P < 0.05). The prevalence of obstructive sleep apnea syndrome (OSAS) and primary aldosteronism (PA) in 2008 increased 38.3 and 1.8 times respectively than in 1999 (χ(2) = 304.025, P < 0.001; χ(2) = 42.845, P < 0.001) and other SH remained unchanged. (3) The prevalence of PA complicated with OSAS increased significantly in recent five years (χ(2) = 26.376, P < 0.001). Incidence of OSAS was 23.9% in PA patients and incidence of PA was 6.7% in OSAS patients. CONCLUSIONS: With the insights gained on hypertension mechanism and the development of new diagnostic technology, percent of diagnosed SH increased remarkably in recent years in hospitalized hypertensive patients in our department of hypertension. OSAS and PA are the leading causes of SH.


Assuntos
Hipertensão/etiologia , Pacientes Internados , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Hospitais Especializados , Humanos , Hipertensão/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
9.
Zhonghua Xin Xue Guan Bing Za Zhi ; 35(8): 706-9, 2007 Aug.
Artigo em Zh | MEDLINE | ID: mdl-17963627

RESUMO

OBJECTIVE: To investigated the association between the +491C/T polymorphism of beta2-AR gene and risk of essential hypertension (EH) in Kazakns of Xinjiang. METHODS: In this population-based case-control study, we recruited 507 Kazakns subjects (289 EH and 218 normotensives, aged from 30 - 60 years old) from the pastoral areas in Xinjiang. Peripheral blood were collected and the DNA was extracted by means of a standard phenol-chloroform method. The +491C/T genotypes of beta2-AR was identified by PCR-restriction fragment length polymorphism analysis. The distribution of genotypic and allelic frequencies between EH and controls were also compared. RESULTS: The frequencies of the genotype CC, CT were 98.82% and 1.18%, respectively and there was no TT genotype in this population, the genotype distribution was consistent with Hardy-Weinberg equilibrium (chi2 = 0.018, P = 0.893). CC and CT genotypic frequencies were 97.92% and 2.08% respectively in EH, while there was no CT genotype in normotensives. The allelic frequencies of C, T were significantly different between EH (98.96%, 1.04%) and normotensives (100%, 0%, all P = 0.040). Systolic blood pressure and diastolic blood pressure were similar in subjects with various genotypes in the whole population (P > 0.05) but systolic blood pressure was significantly higher in males with CT genotype compared with males with CC genotype (P = 0.046). CONCLUSION: The +491C/T polymorphism of beta2-AR gene is associated with essential hypertension and is a possible susceptible factor for essential hypertension in Kazakns of Xinjiang.


Assuntos
Hipertensão/etnologia , Hipertensão/genética , Polimorfismo de Nucleotídeo Único , Receptores Adrenérgicos beta 2/genética , Povo Asiático/genética , Pressão Sanguínea , Estudos de Casos e Controles , Frequência do Gene , Genótipo , Humanos , Estudos de Amostragem
10.
Artigo em Zh | MEDLINE | ID: mdl-16824339

RESUMO

OBJECTIVE: To investigate the protective efficacy of propofol against paraquat induced lung injury. METHODS: One hundred and twenty-eight male Wistar rats were randomizedly divided into three groups: the control group (n = 8), the intoxication group (n = 60) and the propofol group (n = 60). One hundred and twenty rats were once administered with 5 mg/kg paraquat (PQ) by the intragastrical injection to establish the model of PQ induced lung injury. The propofol of 10 mg/kg was administered intraperitoneally in the propofol group (60 rats) twice a day for four consecutive days one hour after the rats were intoxicated while the normal saline of the same amount as propofol in the propofol group was administered in the intoxication group (60 rats) one hour after the rats were intoxicated. The intragastrical injection of 1 mg/kg normal saline was administered once in the control group (8 rats). On the first, the third, the seventh, the 14th and the 28th day after treating, the level of malondialdehyde (MDA) in plasma, bronchoalveolar lavage fluid (BALF) and lung homogenate, and the content of hydroxyproline (HPY) in lung homogenate, the cell count of BALF were detected. Meanwhile, pathological changes of lung were examined under optical microscope. RESULTS: The level of MDA in plasma on the first, the third and the seventh day and in BALF and lung homogenate on the first and the third day in the propofol group [in plasma: (4.31 +/- 0.94), (4.04 +/- 0.87) and (3.24 +/- 1.14) nmol/ml; in BALF: (3.47 +/- 1.09) and (2.79 +/- 1.11) nmol/ml; in lung homogenate: (7.54 +/- 0.63) and (8.41 +/- 1.23) nmol/ml] were significantly lower than those in the intoxication group [in plasma: (10.15 +/- 3.15), (6.97 +/- 1.6 5) and (5.44 +/- 0.66) nmol/ml; in BALF: (5.58 +/- 1.19) and (4.86 +/- 1.89) nmol/ml; in lung homogenate: (10.20 +/- 2.43) and (10.71 +/- 171) nmol/ml, P < 0.05 or P < 0.01]. The total cell count of BALF on the first, the third and the seventh day after intoxication in the propofol group was significantly less than that in the intoxication group respectively (P < 0.05). The histological changes such as alveolar edema, hemorrhage and inflammatory cell infiltration in the propofol group were less than those in the PQ group. CONCLUSION: Propofol could reduce the level of MDA and relieve paraquat induced lung injury.


Assuntos
Paraquat/intoxicação , Propofol/farmacologia , Síndrome do Desconforto Respiratório/prevenção & controle , Animais , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/citologia , Hidroxiprolina/metabolismo , Pulmão/metabolismo , Pulmão/patologia , Masculino , Malondialdeído/metabolismo , Distribuição Aleatória , Ratos , Ratos Wistar , Síndrome do Desconforto Respiratório/induzido quimicamente , Síndrome do Desconforto Respiratório/metabolismo
12.
Artigo em Zh | MEDLINE | ID: mdl-20079060

RESUMO

OBJECTIVE: To investigate the effect of arsenic trioxide (As2O3) on expression of anti-oncogene RAS association domain family gene 1A(RASSF1A) in nasopharyngeal carcinoma cell line CNE-2Z. METHODS: CNE-2Z cells were treated with various concentrations of As2O3 for different times. The IC(50) values were detected by trypan blue stain assay. Cell cycle redistribution was analyzed by flow cytometry. The final concentration 2 micromol/L, 1 micromol/L, 0.5 micromol/L of As2O3 was added to CNE-2Z cell for succedent experiments. The controls and no drugs of CNE-2Z cells were cultivated for 48 h. Methylation specific PCR was used to detect the change of methylation status of RASSF1A gene. The expression of RASSF1A gene was detected by reverse transcription PCR and Western blot at mRNA and protein level. RESULTS: The suppression of cell proliferation by As2O3 was time and dose-dependent. After being treated with As2O3, the IC(50) values of As2O3 were (1.50 +/- 0.05), (1.09 +/- 0.13), (0.65 +/- 0.04) micromol/L at 24, 48, and 72 h, respectively. As2O3 also arrested CNE-2Z cells in G2/M phase of cell cycle. After the effect of As2O3, the methylation of RASSF1A gene became weaker by increasing the concentration of As2O3; and the expression of RASSF1A gene became stronger at mRNA and protein level. Between different concentration of As2O3 group and no drugs group, the differences had statistical significance (P < 0.05). Along with increasing the concentration of As2O3, the expression of RASSF1A gene became stronger at mRNA and protein level, the methylation of RASSF1A gene became weaker and weaker. CONCLUSIONS: As2O3 can activate the expression of RASSF1A gene to inhibit the cell cycle progress of nasopharyngeal carcinoma cell line.


Assuntos
Arsenicais/farmacologia , Ciclo Celular/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , Neoplasias Nasofaríngeas/metabolismo , Óxidos/farmacologia , Proteínas Supressoras de Tumor/metabolismo , Trióxido de Arsênio , Linhagem Celular Tumoral , Expressão Gênica , Humanos , Neoplasias Nasofaríngeas/patologia , RNA Mensageiro/genética
13.
Huan Jing Ke Xue ; 30(11): 3393-8, 2009 Nov.
Artigo em Zh | MEDLINE | ID: mdl-20063760

RESUMO

A FACE (Free-air component enrichment) system in a rice/wheat rotation field was used to investigate the effects of arbuscular mycorrhizal fungal (AMF) inoculation on wheat growth and soil microbial biomass under elevated tropospheric O3 concentration. The elevated O3 concentration tended to increase AM colonization of wheat seedling and bate plant growth during the booting period, then significantly (p < 0.05) reduced aerial biomass, individual yield and kernel weight by 22%, 29% and 9%, respectively, and decreased soil microbial biomass N by 37% after wheat harvesting. However, the total N content in wheat grain significantly (p < 0.05) increased from 2.2% to 2.6%. Under elevated O3 concentration, AMF inoculation accelerated AM colonization successfully, and improved colonization rate and aerial biomass significantly (p < 0.05) during the booting period, thus reduced the damage of aerial biomass by 50% when harvesting, and increased soil microbial biomass N significantly (p < 0.05) related to the noninoculated treatment. Although wheat yield didn't increase, the total N content in grain decreased to the same level of that of the control wheat. It suggested that higher AM colonization is the resistance behavior of wheat in response to O3 intimidation, and AMF inoculation can accelerate wheat growth, increase root exudates and soil microbial biomass subsequencely.


Assuntos
Poluentes Atmosféricos/toxicidade , Micorrizas/fisiologia , Ozônio/toxicidade , Triticum/efeitos dos fármacos , Triticum/microbiologia , Biomassa , Contagem de Colônia Microbiana , Micorrizas/crescimento & desenvolvimento , Microbiologia do Solo , Triticum/crescimento & desenvolvimento
14.
Ying Yong Sheng Tai Xue Bao ; 19(9): 1977-82, 2008 Sep.
Artigo em Zh | MEDLINE | ID: mdl-19102312

RESUMO

The microbial number, microbial biomass, and enzymatic activities in five upland soils under agricultural utilization for 50-700 years were determined, with the correlations between soil microbiological characteristics and agricultural utilization duration analyzed. In the meantime, the functional diversity of microbes in soils having been utilized for 50, 100, and 700 years were investigated. The results showed that at the early stage (< 100 years) of agricultural utilization, the number of soil fungi (F) had a slight increase, while the bacterial number (B), B/F ratio, microbial biomass C (C(mic)), microbial biomass N (N(mic)), and the activities of catalase, invertase and urease all decreased markedly. After utilized for more than 100 years, the F decreased significantly, while the B, B/F ratio, C(mic), N(mic), and the activities of test enzymes all tended to increase. During the whole utilization period from 50 to 700 years, the C(mic)/N(mic) ratio had a significant increase with year. The Shannon, Simpson, and McIntosh indices of soil microbial community had the same responses to the agricultural utilization duration as the bacterial number, microbial biomass, and enzymatic activities. All of these indicated that in the upland fields in Cixi of Zhejiang Province, shifts of soil microbial community occurred with increasing agricultural utilization duration, and soil microbiological quality had an overall increase after 100 years agricultural utilization.


Assuntos
Produtos Agrícolas/crescimento & desenvolvimento , Ecossistema , Microbiologia do Solo , Solo/análise , Catalase/análise , China , Contagem de Colônia Microbiana , Fatores de Tempo , Urease/análise , beta-Frutofuranosidase/análise
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