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1.
Ying Yong Sheng Tai Xue Bao ; 26(4): 1077-82, 2015 Apr.
Artículo en Chino | MEDLINE | ID: mdl-26259449

RESUMEN

A field experiment was conducted to understand the decomposition rates and chemical composition changes of leaf litter in logging residues of a 35-year-old secondary Castanopsis carlesii plantation over a period of one year. Mass loss rate of leaf litter showed an exponential decrease with time from May 2012 to April 2013, with a total 80% loss of initial dry mass. Net potassium (K) release was observed during this period, with only 5% of initial K remained. Nitrogen ( N) featured a pattern of accumulation at the early stage and release later, while phosphorus (P) exhibited a sequence of release, accumulation, and release. The remaining of N and P were 19% and 16% of their initial mass, respectively. The release rate was highest for K and the lowest for N. Decomposition of lignin indicated a trend of release-accumulation-release from May 2012 to October 2012, with no further significant change from November 2012 to the end of the experiment. The concentration of cellulose nearly unchanged during the experiment. The N/P rate increased with decomposition, ranging from 18.6 to 21.1. The lignin/N rate fluctuated greatly at the early stage and then almost stabilized thereafter.


Asunto(s)
Fagaceae , Agricultura Forestal , Bosques , Hojas de la Planta , Suelo/química , Lignina/análisis , Nitrógeno/análisis , Fósforo/análisis , Potasio/análisis , Árboles
2.
Ying Yong Sheng Tai Xue Bao ; 25(8): 2201-8, 2014 Aug.
Artículo en Chino | MEDLINE | ID: mdl-25509068

RESUMEN

In this paper, monthly variation of dissolved organic matter (DOM) concentrations as well as humification and aromaticity indices in throughfall and stemflow from secondary broadleaved Castanopsis carlesii (BF) forest and Cunninghamia lanceolata plantation (CP) were measured. The DOC concentrations in throughfall were significantly higher with greater variation in BF than in CP. The concentrations of DOC in throughfall were averagely 7.2 and 3.2 times of those in rainfall in BF and CP forests, respectively. The DOC concentrations of stemflow in CP were averagely 2.5 times as much as those in BF, and the DOC concentrations in stemflow tended to be greater in dry season than in rain season for the two forests. A significantly negative relationship was' found between the DOC concentrations in stemflow and the amounts of stemflow for both BF and CP. Moreover, the humification and aromaticity indices of DOM in throughfall in BF was significantly greater than in CP. In contrast, the humification and aromaticity indices of DOM from stemflow of CP were significantly greater than those of BF. This result indicated that the structure of DOM from throughfall was more complex in BF than in CP, and the structure of DOM from stemflow was vice versa. These results indicated that DOM in stemflow and throughfall showed significant variations in quantity and quality between BF and CP and may greatly impact the accumulation of soil organic carbon.


Asunto(s)
Cunninghamia , Fagaceae , Bosques , Lluvia , Suelo , Árboles
3.
Zhonghua Wei Chang Wai Ke Za Zhi ; 16(11): 1035-40, 2013 Nov.
Artículo en Chino | MEDLINE | ID: mdl-24277396

RESUMEN

OBJECTIVE: To systematically assess the effect of early enteral nutrition support after gastrointestinal operation on prognosis. METHODS: The Cochrane Library, PubMed, CBM, CNKI, Wanfang, and VIP databases were retrieved via computer system for randomized controlled trails(RCTs) with early enteral nutrition support to patients undergoing gastrointestinal operation. Quality of studies was evaluated by the Cochrane Jadad rating scale. Nutrition indexes, bowel function indices, postoperative complications, health-economics indices were collected. Meta-analysis was conducted with RevMan 5.2. RESULTS: Eleven relevant RCTs studies with 1087 cases were enrolled, including 541 patients in the study group(early enteral nutrition) and 546 in the control group. Meta-analysis showed that patients in the study group had significantly higher levels of plasma albumin and prealbumin than those in the control group(WMD=2.87, 95%CI:1.03-4.71; WMD=0.04, 95%CI:0.02-0.05). The time of postoperative bowel ventilation in the study group was significantly shorter than that in the control group(WMD=4.10, 95%CI:-5.38--2.82). The postoperative complication rate in the study group was significantly lower as compared to the control group(RR=0.64, 95%CI:0.44-0.93). CONCLUSION: Early enteral nutrition support after gastrointestinal operation is safe and effective, which can improve the nutritional status, promote bowel function return, and reduce postoperative complication rate.


Asunto(s)
Nutrición Enteral , Enfermedades Gastrointestinales/cirugía , Procedimientos Quirúrgicos del Sistema Digestivo , Humanos , Complicaciones Posoperatorias , Pronóstico , Ensayos Clínicos Controlados Aleatorios como Asunto
4.
Tumour Biol ; 34(6): 3801-6, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23873107

RESUMEN

Several case-control studies on the relation between matrix metalloproteinase (MMP)-1 gene -1607 1G>2G polymorphism and colorectal cancer do not have similar conclusions. The previous two meta-analyses focusing on the same issue also were inconsistent. To further evaluate the relation between the MMP-l gene polymorphism and colorectal cancer, we selected eight case-control studies related to MMP-1 gene polymorphism and colorectal cancer by searching MEDLINE, Embase, CANCERLIT, American Association for Cancer Research, Chinese Biomedical Literature Database, Chinese CNKI, and Wanfang database. Q test and I (2) test were used to test the heterogeneity. We utilized the random effects model to calculate the odds ratio (OR), 95% confidence interval (CI), and the overall effect of P value using the RevMan 5.2 software. The present study included 1,403 patients with colorectal cancer and 1,754 healthy control subjects. Both -1607 2G/2G genotype carriers [OR = 1.59, 95 % CI (1.27-2.01); P < 0.001] and the -1607 2G allele carriers [OR = 1.26, 95% CI (1.05-1.51); P = 0.01] were found to have an increased risk of colorectal cancer. Therefore, we concluded that MMP-1 -1607 1G>2G polymorphism was associated with colorectal cancer.


Asunto(s)
Neoplasias Colorrectales/genética , Predisposición Genética a la Enfermedad/genética , Metaloproteinasa 1 de la Matriz/genética , Polimorfismo de Nucleótido Simple , Estudios de Casos y Controles , Frecuencia de los Genes , Genotipo , Humanos , Oportunidad Relativa
5.
Int J Mol Sci ; 13(5): 6399-6406, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22754372

RESUMEN

CD146 has been regarded as a novel potential therapeutic target for multiple cancers. The aim of the study was to investigate the expression of CD146 in gastric cancer and evaluate its clinical-pathological and prognostic significance. The expression of CD146 and three epithelial-mesenchymal transition (EMT)-related proteins (E-cadherin, ß-catenin and vimentin) was examined in 144 gastric cancers by immunohistochemistry. Fifty-nine cases (41.0%) were defined as positive for CD146 expression. We found that CD146 expression correlated positively with lymph node involvement and a poor prognosis, and retained an independent prognostic factor for gastric cancer patients. Furthermore, positive expression of CD146 was strongly associated with loss of the epithelial marker E-cadherin and acquisition of the expression of the mesenchymal markers nuclear ß-catenin and vimentin. These findings suggest that CD146 might promote EMT and progression in gastric cancer, and thus may be a potential therapeutic target for patients with gastric cancers.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Transición Epitelial-Mesenquimal , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patología , Adulto , Anciano , Anciano de 80 o más Años , Antígeno CD146/metabolismo , Femenino , Humanos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Pronóstico
6.
World J Gastroenterol ; 17(4): 540-2, 2011 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-21274386

RESUMEN

Granulocytic sarcoma (GS) is an extramedullary tumor mass consisting of immature myeloid cells. Isolated pancreatic granulocyte sarcoma is extremely rare. We report a very unusual pancreatic granulocytic sarcoma in a patient without acute myeloid leukemia. The patient presented with acute epigastric pain because of splenic infarction due to a mass consisting of myeloblasts in the pancreatic tail. The patients underwent splenectomy and distal pancreatectomy. Pathology and immunohistochemistry suggested a GS. Despite local surgery, an isolated tumor recurred 2 mo after operation and the patient died 3 mo after removal of the tumor. Only 7 reported cases of pancreatic GS were identified in the literature and the mass was located in the pancreatic head. This is the first report of GS in the pancreatic tail with splenic infarction.


Asunto(s)
Neoplasias Pancreáticas/diagnóstico , Sarcoma Mieloide/diagnóstico , Resultado Fatal , Femenino , Humanos , Persona de Mediana Edad , Páncreas/patología , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/cirugía , Sarcoma Mieloide/patología , Sarcoma Mieloide/cirugía
7.
Biomed Environ Sci ; 19(5): 380-4, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17190192

RESUMEN

OBJECTIVE: To investigate the current status of disabled children and prevalence of disabilities in children aged 0-6 years and their risk factors, and to provide scientific evidence for making relevant policies for disabled children. METHODS: In a community-based cross-sectional study, multi-phase, stratified, unequal proportional and cluster sampling was adopted to survey 60 124 children aged 0-6 years. All the investigated children were screened for disabilities, and those with positive screening tests were further diagnosed by various specialties. RESULTS: A total of 819 children were diagnosed as disabled with an overall prevalence of 1.362%, 0.155% for hearing disability, 0.160% for visual disability, 0.931% for intelligent disability, 0.424% for limb disability, and 0.101% for mental disability. Prevalence of disability in children was higher in rural areas, and in families with two or more children, low educational level or in divorced families. CONCLUSION: The prevalence of disability can be reduced by economic development, improvement of health care and quality of population, as well as harmonious familial relationship, early prevention of disability, and preschool education for disabled children.


Asunto(s)
Ceguera/epidemiología , Pérdida Auditiva/epidemiología , Discapacidad Intelectual/epidemiología , Deformidades Congénitas de las Extremidades/epidemiología , Niño , Preescolar , China/epidemiología , Personas con Discapacidad , Humanos , Lactante , Recién Nacido
8.
Ai Zheng ; 22(3): 295-7, 2003 Mar.
Artículo en Chino | MEDLINE | ID: mdl-12654190

RESUMEN

BACKGROUND & OBJECTIVE: The early diagnosis of pancreatic carcinoma is difficult. The serum tumor markers such as CA19-9 have a relatively high sensitivity but with low specificity. The oncogene K-ras is frequently mutated in pancreatic carcinoma and with high specificity. The aim of this study was to assess the feasibility of detection of K-ras mutation combined with serum content of CA19-9 as an approach for diagnosis of pancreatic carcinoma. METHODS: Serum DNA was extracted from 39 patients with pancreatic carcinoma. Mutation enriched polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to determine codon 12 mutations of K-ras. Serum content of CA19-9 was determined by radioimmunoassay. In addition, the sera from 17 patients with other pancreatic diseases and 21 healthy individuals were also analyzed as control. RESULTS: K-ras gene mutations at codon 12 were detected in the sera of 71.79%(28/39) patients with pancreatic carcinoma and 11.76%(2/17) of patients with benign pancreatic tumors. The positive rates of CA19-9 were 71.79% and 41.18%, respectively. Parallel combined test increased the diagnostic sensitivity to 94.87%; and serial combined test increased the diagnostic specificity to 94.12%. Negative results of K-ras gene and CA19-9 were obtained in all sera from healthy controls. CONCLUSION: Combined detection of K-ras mutation and CA19-9 could increase the sensitivity and specificity in diagnosing pancreatic carcinoma, and would seem to be merited in clinic.


Asunto(s)
Biomarcadores de Tumor/sangre , Antígeno CA-19-9/sangre , Genes ras , Neoplasias Pancreáticas/diagnóstico , Adulto , Anciano , Biomarcadores de Tumor/genética , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mutación , Neoplasias Pancreáticas/sangre , Neoplasias Pancreáticas/genética , Polimorfismo de Longitud del Fragmento de Restricción , Pronóstico
9.
Ai Zheng ; 21(8): 838-42, 2002 Aug.
Artículo en Chino | MEDLINE | ID: mdl-12478888

RESUMEN

BACKGROUND & OBJECTIVE: 5-Fluorouracil(5-FU), a widely used chemotherapeutic drug, has a limited overall effect in the treatment of human solid tumors due to resistance. This study was designed to investigate if antitumor activation of 5-FU could be enhanced by transfection of uracil phosphoribosyltransferase(UPRT) gene. METHODS: The UPRT gene encoding uracil phosphoribosyltransferase was amplified from Escherichia Coli K12 genome and subcloned into retrovirus expression vector pLXSN, Recombinant retrovirus was packaged and used further to infect murine gastric cancer cell line MFC. The sensitivity of MFC transfected with UPRT gene to 5-FU was determined by MTT method. In situ gene therapy was performed by regional repeated injections of concentrated and purified recombinant retrovirus carrying UPRT gene intratumorally and followed by administration of 5-FU intraperitoneally(i.p.). RESULTS: The 5-FU sensitivity in MFC transfected with the UPRT gene increased 17.26-fold compared to the control cells. In situ transfection of the UPRT gene mediated by retrovirus vector followed by the administration of 5-FU (10 mg/kg) significantly inhibited the tumor growth (P < 0.005) with an inhibition rate of 87.18% and prolonged the survival. CONCLUSION: Transfection of UPRT gene can render the murine gastric cancer cell line MFC be more sensitive to low concentration of 5-FU and significantly improve the antitumor effect of 5-FU both in vitro and in vivo.


Asunto(s)
Antimetabolitos Antineoplásicos/uso terapéutico , Fluorouracilo/uso terapéutico , Terapia Genética/métodos , Pentosiltransferasa/genética , Neoplasias Gástricas/terapia , Animales , División Celular/efectos de los fármacos , División Celular/genética , ADN de Neoplasias/genética , Femenino , Regulación Enzimológica de la Expresión Génica , Vectores Genéticos/genética , Ratones , Reacción en Cadena de la Polimerasa , Profármacos/uso terapéutico , Retroviridae/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/patología , Factores de Tiempo , Células Tumorales Cultivadas
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