Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 170
Filtrar
1.
Zhonghua Yi Xue Za Zhi ; 104(20): 1844-1851, 2024 May 28.
Artigo em Zh | MEDLINE | ID: mdl-38782753

RESUMO

Objective: To investigate the correlation between hematocrit (HCT) and cardiovascular events in peritoneal dialysis (PD) patients. Methods: Patients undergoing maintenance PD in the PD center of Guizhou Provincial People's Hospital from March 19, 2012 to July 9, 2020 were included. Demographic, baseline clinical and laboratory data of the patients were collected and patients were followed up until April 8, 2022. The primary endpoint was the first occurrence of a cardiovascular event. According to the tertiles of baseline HCT, the patients were divided into group Q1 (HCT≤26.6%), group Q2 (HCT>26.6%-32.4%), and group Q3 (HCT>32.4%). Laboratory indexes and cardiovascular events were compared among the three groups. Kaplan-Meier survival curve, Cox regression analysis and sensitivity analysis were used to analyze the effect of HCT on cardiovascular outcomes. Receiver operating characteristic (ROC) curve was used to analyze the predictive value of HCT for cardiovascular events in PD patients. Results: A total of 860 PD patients were included, including 494 males (57.4%) and 366 females (42.6%), with a mean age of (41.5±15.0) years. There were 287 cases in group Q1, 289 cases in group Q2, and 284 cases in group Q3, respectively. A total of 265 (30.8%) patients experienced first cardiovascular events during the follow-up period. The incidence of cardiovascular events in groups Q1, Q2 and Q3 was 36.2% (104/287), 34.3% (99/289), and 21.8% (62/284), respectively, with a statistically significant difference (P<0.001). The incidence of cardiovascular events decreased with the increase of HCT. Multivariate Cox proportional hazards regression model analysis showed that decreased HCT was a risk factor for cardiovascular events. Compared with group Q3, the risk of cardiovascular events in group Q1 increased by 50.7% (group Q2: HR=1.444, 95%CI: 1.029-2.028, P=0.034; group Q1: HR=1.570, 95%CI: 1.096-2.250, P=0.014). In the sensitivity analysis, using kidney transplantation as the competition event, the risk of cardiovascular events was lower in group Q3 than that in group Q1 (subdistributional HR=1.413, 95%CI: 1.006-1.990, P=0.046). Kaplan-Meier survival curve showed that compared with the other two groups, the cardiovascular events-free survival rate of patients in group Q1 was significantly lower (log-rank χ2=9.722, P=0.008). ROC analysis showed that the area under the curve (AUC) of HCT for predicting cardiovascular events in PD patients was 0.583 (95%CI: 0.542-0.623, P<0.001), with the sensitivity of 40.6% and the specificity of 75.1%. Conclusion: Low-level HCT is associated with an increased risk of the first cardiovascular event in PD patients.


Assuntos
Doenças Cardiovasculares , Diálise Peritoneal , Humanos , Masculino , Feminino , Estudos Retrospectivos , Doenças Cardiovasculares/etiologia , Adulto , Pessoa de Meia-Idade , Hematócrito , Fatores de Risco , Modelos de Riscos Proporcionais
2.
Zhonghua Gan Zang Bing Za Zhi ; 39(1): 32-35, 2023 Jan 15.
Artigo em Zh | MEDLINE | ID: mdl-36776012

RESUMO

The clinical data of maintenance hemodialysis (MHD) patients from twenty hemodialysis centers in Guizhou province from June to September 2020 were collected by cross-sectional study. The patients were divided into AFD group and non-AFD group according to whether AFD had occurred. LTI was measured by body composition monitor. The results showed that the incidence of AFD in 2 781 MHD patients was 30.0% (835/2 781). Median LTI level was 15.2 (13.2, 17.5) kg/m2. The LTI level in the AFD group was higher than that in the non-AFD group (P < 0.05). According to the tertiles of LTI, low LTI group (LTI ≤ 13.9 kg/m2) had the highest incidence of AFD (35.5%, 334/940), and the high LTI group had the lowest incidence of AFD (26.3%, 241/916), and the difference among the three groups was statistically significant (χ2=20.182,P < 0.001). Multivariate logistic regression analysis showed that low LTI group as the reference, the risk of AFD in moderate LTI group (13.9 kg/m2 < LTI ≤ 16.6 kg/m2) and high LTI group were associated with the 20.0% (OR=0.800, 95% CI 0.650-0.986, P=0.036) and 22.8% (OR=0.772, 95% CI 0.616-0.966, P=0.024) decrease, respectively. These results suggest that low LTI level is independently associated with an increased risk of AFD in MHD patients.


Assuntos
Composição Corporal , Diálise Renal , Humanos , Estudos Transversais , Diálise Renal/efeitos adversos
3.
Zhonghua Zhong Liu Za Zhi ; 44(7): 634-666, 2022 Jul 23.
Artigo em Zh | MEDLINE | ID: mdl-35880331

RESUMO

Gastric cancer (GC) is a major digestive tract malignancy in China, which seriously threatens the health of Chinese population. A large number of researches have demons-trated that screening, early detection and early treatment are effective in reducing the incidence and mortality of GC. The development of the guideline for GC screening, early detection and early treatment in line with epidemic characteristics of GC in China will greatly promote the homogeneity and standardization, and improve the effect of GC screening. This guideline was commissioned by the Bureau of Disease Control and Prevention of the National Health Commission. The National Cancer Center of China initiated and convened a working group comprising multidisciplinary experts. Following the World Health Organization Handbook for Guideline Development, this guideline combined the most up-to-date evidence of GC screening, China's national conditions, and practical experience in cancer screening. This guideline provided evidence-based recommendations with respect to the screening population, technology and procedure management, aiming to improve the effect of GC screening and provide scientific evidence for the GC prevention and control in China.


Assuntos
Detecção Precoce de Câncer , Neoplasias Gástricas , Pequim , China/epidemiologia , Detecção Precoce de Câncer/métodos , Humanos , Programas de Rastreamento , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/prevenção & controle
4.
Zhonghua Zhong Liu Za Zhi ; 44(6): 491-522, 2022 Jun 23.
Artigo em Zh | MEDLINE | ID: mdl-35754225

RESUMO

Esophageal cancer (EC) is a major digestive tract malignancy in China, which seriously threatens the health of Chinese population. A large number of researches have demonstrated that screening and early detection are effective in reducing the incidence and mortality of EC. The development of the guideline for EC screening and early detection in line with epidemic characteristics of EC in China will greatly promote the homogeneity and standardization, and improve the effect of EC screening. This guideline was commissioned by the Bureau of Disease Control and Prevention of the National Health Commission. The National Cancer Center of China initiated and convened a working group comprising multidisciplinary experts. Following the World Health Organization Handbook for Guideline Development, this guideline combined the most up-to-date evidence of EC screening, China's national conditions, and practical experience in cancer screening. This guideline provided evidence-based recommendations with respect to the screening population, technology and procedure management, aiming to improve the effect of EC screening and provide scientific evidence for the EC prevention and control in China.


Assuntos
Detecção Precoce de Câncer , Neoplasias Esofágicas , Pequim , China/epidemiologia , Detecção Precoce de Câncer/métodos , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/prevenção & controle , Humanos , Programas de Rastreamento
5.
Beijing Da Xue Xue Bao Yi Xue Ban ; 54(3): 572-577, 2022 Jun 18.
Artigo em Zh | MEDLINE | ID: mdl-35701138

RESUMO

OBJECTIVE: To explore the feasibility of preparing compound tablets for the treatment of hypertension by fused deposition modeling (FDM) 3D printing technology and to evaluate the quality of the printed compound tablets in vitro. METHODS: Polyvinyl alcohol (PVA) filaments were used as the exci-pient to prepare the shell of tablet. The ellipse-shaped tablets (the length of major axes of ellipse was 20 mm, the length of the minor axes of ellipse was 10 mm, the height of tablet was 5 mm) with two separate compartments were designed and printed using FDM 3D printer. The height of layer was 0.2 mm, and the thickness of roof or floor was 0.6 mm. The thickness of shell was 1.2 mm, and the thickness of the partition wall between the two compartments was 0.6 mm. Two cardiovascular drugs, captopril (CTP) and hydrochlorothiazide (HCT), were selected as model drugs for the printed compound tablet and filled in the two compartments of the tablet, respectively. The microscopic morphology of the tablets was observed by scanning electron microscopy (SEM). The weight variation of the tablets was investigated by electronic scale. The hardness of the tablets was measured by a single-column mechanical test system. The contents of the drugs in the tablets were determined by high performance liquid chromatography (HPLC), and the dissolution apparatus was used to measure the in vitro drug release of the tablets. RESULTS: The prepared FDM 3D printed compound tablets were all in good shape without printing defects. The average weight of the tablets was (644.3±6.55) mg. The content of CTP and HCT was separately (52.3±0.26) mg and (49.6±0.74) mg. A delayed in vitro release profile was observed for CTP and HCT, and the delayed release time for CTP and HCT in vitro was 20 min and 40 min, respectively. The time for 70% of CTP and HCT released was separately 30 min and 60 min. CONCLUSION: CTP and HCT compound tablets were successfully prepared by FDM 3D printing technology, and the printed tablets were of good qualities.


Assuntos
Captopril , Hidroclorotiazida , Citidina Trifosfato , Liberação Controlada de Fármacos , Impressão Tridimensional , Comprimidos/química , Tecnologia Farmacêutica/métodos
6.
Artigo em Inglês | MEDLINE | ID: mdl-36567804

RESUMO

As one of the most polluted provinces in China, air pollution events occur frequently in Shandong. Based on the hourly (or daily) concentrations of six air pollutants (PM2.5, PM10, O3, NO2, SO2 and CO), the situations of air quality improvement in three kinds of cities (key cities, coastal cities and general cities) are assessed comprehensively during 2014-2020. Contrary to the daily maximum 8-h average ozone (MDA8 O3), the annual average concentrations of other pollutants show the downward trends during 2014-2020. Therein, the improvement rates of annual average concentrations of air pollutants in key cities are highest. By 2020, the day proportions of O3 as the primary pollutant are up to 38% in three kinds of cities. Besides, due to the impact of COVID-19, the monthly average concentrations of PM2.5, PM10, NO2, SO2 and CO in February 2020 decrease by 32.1-49.5% year-on-year. There are still about 50% of population exposed to high-risk regions (R i > 2), which are mainly concentrated in main urban areas and industrial areas. Thus, the adjustment of industrial structure and energy composition in the context of carbon peak and carbon neutrality should be implemented in the future. Supplementary Information: The online version contains supplementary material available at 10.1007/s13762-022-04651-5.

7.
Zhonghua Yi Xue Za Zhi ; 100(24): 1866-1871, 2020 Jun 23.
Artigo em Zh | MEDLINE | ID: mdl-32575929

RESUMO

Objective: To investigate the rule of mediastinal lymph node metastasis of papillary thyroid carcinoma and the application of therapeutic mediastinal lymph node dissection through the sternotomy approach in the treatment of mediastinal lymph node metastasis of papillary thyroid carcinoma. Methods: All cases of papillary thyroid carcinoma with mediastinal lymph node metastasis treated through sternotomy cooperated by thoracic surgeons and head and neck surgeons from January 2006 to January 2017 in Cancer Hospital of Chinese Academy of Medical Sciences were included in this study. The distribution, metastasis rate, metastasis degree, surgical method, surgical complications and postoperative survival of patients with mediastinal lymph node metastasis were retrospectively analyzed. Results: A total of 31 patients (16 males and 15 females) with papillary thyroid cancer with mediastinal lymph node metastasis, with a median age of 46 (19-65) years, were enrolled in the group. Partial upper sternotomy was used in 28 cases, and total sternotomy was used in 3 cases. The mediastinal lymph nodes of papillary thyroid carcinoma metastasized farthest to the station 6, and the lymph node metastasis rate of each group from high to low was: 2R (61%), 1R (39%), 3A (39%), 1L (16%), 2L (10%), 4R (10%), 5 (3%) and 6 (3%). No metastasis was observed in station 3P, 4L and 7. In addition, the degree of lymph node metastasis at station 2R was the highest, reaching 35% (77/219). Extra-nodal invasion of mediastinal metastatic lymph nodes in thyroid papillary carcinoma is common (23%), easily fuses into masses (23%) and invades peripheral vascular nerves (26%). Up to 29% of blood transfusions are required during or after surgery due to oozing or bleeding (9/31). The 1-, 3-, 5-and 10-year survival rates of patients undergoing surgical treatment were 94%, 94%, 87% and 81%, respectively. Conclusion: Papillary thyroid carcinoma can metastasize to almost all mediastinal lymph nodes except station 3P, 4L and 7. Radical mediastinal lymph node dissection through sternotomy is an effective method for the treatment of mediastinal lymph node metastasis of thyroid papillary carcinoma.


Assuntos
Carcinoma Papilar , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide , Idoso , Feminino , Humanos , Excisão de Linfonodo , Linfonodos , Masculino , Pessoa de Meia-Idade , Esvaziamento Cervical , Estudos Retrospectivos , Esternotomia , Tireoidectomia
8.
Ecotoxicol Environ Saf ; 186: 109753, 2019 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-31604159

RESUMO

Nitrite is a common toxic substance in culture systems of Litopenaeus vannamei, and the stress may disturb hemocyanin synthesis and energy metabolism and result in shrimp death. In the present study, nitrite at concentrations of 0 (control), 3.3 (46.2 NO2-N mg/L), 6.6 (92.4) and 9.9 mM (138.6) was used to evaluate the responses of hemocyanin level and energy metabolism in L. vannamei (5.80 ±â€¯0.44 cm, 1.88 ±â€¯0.38 g) for 96 h. The mortality rate at 96 h increased with nitrite concentration (50% at 9.9 mM, 40% at 6.6 mM, 30% at 3.3 mM, and 10% at 0 mM). In general, HIF-1α and hemocyanin mRNA expression in the nitrite stress groups was upregulated from 6 to 12 h and downregulated from 24 to 96 h. In the hemolymph, nitrite levels were significantly elevated in a dose-dependent manner, and exposure to nitrite stress significantly decreased the oxyhemocyanin content from 24 to 96 h. The glucose and lactate levels in the hemolymph in the nitrite stress groups were higher than those in the control group from 12 to 96 h. Compared with the control group, the shrimp in the nitrite stress groups exhibited decreased glycogen concentrations in the hepatopancreas. The triglyceride (TG) levels in the nitrite stress groups were all higher than those in the control group from 48 to 96 h. The hexokinase (HK) activity in the hepatopancreas and muscle increased in the nitrite stress groups from 48 to 96 h. In general, nitrite stress enhanced the activities of pyruvate kinase (PK), phosphofructokinase (PFK) and lactate dehydrogenase (LDH) in muscle from 24 to 96 h. In addition, nitrite stress decreased the activities of succinate dehydrogenase (SDH) and fatty acid synthase (FAS) from 24 to 96 h in the hepatopancreas and muscle. This study indicates that exposure to nitrite stress can enhance the accumulation of nitrite in the hemolymph and then reduce oxygenation and hemocyanin synthesis, leading to tissue hypoxia and thereby resulting in accelerated anaerobic metabolism and the inhibition of aerobic metabolism. The effects of nitrite stress on hemocyanin synthesis and energy metabolism may be one of the reasons for the mortality of L. vannamei in culture systems.


Assuntos
Anaerobiose/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Hemocianinas/metabolismo , Nitritos/toxicidade , Oxigênio/metabolismo , Penaeidae/efeitos dos fármacos , Estresse Fisiológico , Animais , Aquicultura , Glicogênio/metabolismo , Hemolinfa/efeitos dos fármacos , Hemolinfa/metabolismo , Hepatopâncreas/efeitos dos fármacos , Hepatopâncreas/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Músculos/efeitos dos fármacos , Músculos/metabolismo , Penaeidae/crescimento & desenvolvimento , Penaeidae/metabolismo , Alimentos Marinhos , Triglicerídeos/metabolismo
9.
Zhonghua Zhong Liu Za Zhi ; 40(8): 626-630, 2018 Aug 23.
Artigo em Zh | MEDLINE | ID: mdl-30139035

RESUMO

Objective: To evaluate the safety and efficiency of patient-controlled intravenous analgesia (PCIA) using hydromorphone supplement with dexmedetomidine on patients undergoing transcatheter arterial chemoembolization. Methods: One hundred and eighty patients, age ranged from 40 to 65 years, body mass index from 18 to 25 kg/m(2,) ASA physical status Ⅱ-Ⅲ, who were scheduled for transcatheter arterial chemoembolization (TACE) under monitor anesthesia care (MAC) were randomly divided into 3 groups: hydromorphone group (H group), hydromorphone supplement with dexmedetomidine 1 µg/kg group (D1 group), hydromorphone supplement with dexmedetomidine 2 µg/kg group (D2 group), 60 patients in every group. All the groups of patients received PCIA pump, in the H group, the PCIA reagent was composed of 120 µg/kg hydromorphone and 5 mg tropisetron in 100 ml of normal saline. In comparison, PCIA regiment was composed of 120 µg/kg hydromorphone, 1 µg/kg dexmedetomidine and 5 mg tropisetron in 100 ml of normal saline in the D1 group, while 120 µg/kg hydromorphone, 2 µg/kg dexmedetomidine and 5 mg tropisetron in 100 ml of normal saline in the D2 group. The visual analogue scale (VAS) score, the observer's assessment of alertness/sedation scale (OAA/S) score, patients' satisfaction index, consumption of hydromorphone, the additional dose of morphine, the effective pressing times of PCIA and adverse reactions were recorded in detail at 0, 0.5, 1, 4, 12 and 24 hours after the patients underwent TACE. Results: The total consumptions of hydromorphone were (4.3±0.1), (4.1±0.1), and (3.8±0.1) mg in group H, D1, and D2, respectively, and the effective pressing times were 13±3, 6±2 and 2±1, the additional doses of morphine were (30±5), (15±3), and (3±1) mg, and adverse reaction rates were 45.0%, 28.3%, and 10.0%, respectively. The manifestations mentioned above in D2 group were significantly lower than those in group H and group D1 (P<0.05). Immediately and 5 min after embolization, at the end of surgery and 0.5, 1, 4, 12 and 24 h after surgery, the VAS scores in the D2 group were 1.9±0.2, 2.1±0.3, 1.8±0.4, 1.8±0.3, 1.7±0.3, 1.6±0.3, 1.3±0.2, 1.3±0.3, respectively, lower than those in group H and group D1 (P<0.05); The satisfaction index in D2 group at these times were 8.7±1.1, 8.9±0.8, 9.2±0.9, 9.0±0.7, 9.1±0.8, 9.0±0.6, 9.1±0.7, 9.2±0.9, respectively, higher than those in group H and group D1 (P<0.05). No breath depression happened in these three groups. Conclusion: The formula of hydromorphone combined with dexmedetomidine to patients undergoing TACE is greatly safe and efficient, with advantages in alleviating pain, reducing hydromorphone consumption and the incidence of adverse reaction of hydromorphone, and without breath depression.


Assuntos
Analgesia Controlada pelo Paciente/métodos , Analgésicos não Narcóticos/administração & dosagem , Analgésicos Opioides/administração & dosagem , Quimioembolização Terapêutica/métodos , Dexmedetomidina/administração & dosagem , Hidromorfona/administração & dosagem , Administração Intravenosa , Adulto , Idoso , Analgesia Controlada pelo Paciente/efeitos adversos , Analgésicos não Narcóticos/efeitos adversos , Analgésicos Opioides/efeitos adversos , Artérias , Quimioembolização Terapêutica/efeitos adversos , Dexmedetomidina/efeitos adversos , Quimioterapia Combinada , Humanos , Hidromorfona/efeitos adversos , Indóis/administração & dosagem , Pessoa de Meia-Idade , Tropizetrona
11.
Zhonghua Bing Li Xue Za Zhi ; 47(11): 822-826, 2018 Nov 08.
Artigo em Zh | MEDLINE | ID: mdl-30423604

RESUMO

Objective: To investigation HER2 status in gastric adenocarcinoma of Chinese and contributing factors to the HER2 expression. Methods: HER2 status of 40 842 gastric adenocarcinomas and clinical data were retrospectively collected from 23 hospitals dated from 2013 to 2016. The association between HER2 positivity and clinicopathologic features was analyzed. Results: Of the 40 842 patients the median age was 62 years, the male female ratio was 2.6∶1.0. The rate of HER2 positivity was 8.8% (3 577/40 842). HER2 expression was related to the tissue type, tumor location, Lauren classification and tumor differentiation (P values: 0.009, 0.001, <0.01 and <0.01, respectively). Different HER2 expression status was observed between primary and recurrent tumors in 7.6% (48/635) cases. The rates of HER2 positivity ranged from 2% to 10% among different institutions. The rates of HER2 FISH amplification were dramatically different among the 23 hospitals (0-100%) with an average rate of 10% (810/8 156) in patients with HER2 IHC 2+ . Conclusions: HER2 expression is associated with clinicopathologic characteristics. HER2 re-assessment of tumor tissue and use of in situ hybridization techniques increase HER2 positivity. The current retrospective study should reflect the HER2 status in gastric adenocarcinoma of Chinese patients.


Assuntos
Adenocarcinoma/metabolismo , Recidiva Local de Neoplasia/metabolismo , Receptor ErbB-2/metabolismo , Neoplasias Gástricas/metabolismo , Povo Asiático , China , Feminino , Humanos , Imuno-Histoquímica , Hibridização In Situ , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
12.
Artigo em Zh | MEDLINE | ID: mdl-30248731

RESUMO

Objective: To evaluate the effect of acrylamide on the apoptosis of nerve cells by integral cell modelling in vitro which simulates the barrier effect and metabolic micro-environment. Methods: A non-contact and co-cultured in vitro blood brain barrier (BBB) model was established by using human umbilical vein endothelial cells (HUVEC) and rat glioma cells (C6) . The trans-endotheilal electrical resistance (TEER) and horseradish peroxidase (HRP) tracer effects were measured to verify the tight connectivity and permeability of the established BBB model. An integrate discrete multiple organ cell co-culture (idMOC) model was established by inoculating the human renal cortical proximal tubular epithelial cells (HK-2) , human normal hepatocytes (L-02) and human neuroblastoma cells (SH-SY5Y) into the self-made multi-organ plate for co-culturing. Then the model was verified by observing the growth curve of various tissue cells under co-culturing or culturing individually. SH-SY5Y cells were exposed to different concentrations of acrylamide directly and indirectly (through BBB model and idMOC model) . The changes of cell apoptosis rate were analyzed by flow cytometry to explore the impact of model on Acrylamide (ACR) injury of typical neurotoxic agents. Results: HUVEC cells can form a wide range of close-connected complex and then inhibit the external electric field under the cross-endothelial movement, and the mean was lower than that of endothelial cell culture group at 4, 5 and 6 days (P<0.05) ; After 20 min, the penetration rate of HRP in the co-culture group was less than that in the individual culture group, and the difference was statistically significant (P<0.05) , indicating that the barrier function of the co-culture group was higher than that of the individual culture group. All cells can exchange substances through the exchange hole of the culture plate, the cells grow well and there was no obvious death. The growth curve in individual culture group and co-culture group were basically the same, the difference was not statistically significant (P>0.05) . Under the condition of different concentrations of ACR (140, 270 g/ml) , compared with the direct exposure group, the apoptosis rate of the BBB model and the idMOC model were significantly decreased, and the difference was statistically significant (P<0.05) . Conclusion: Based on HUVEC cells and C6 cells co-culture system, a blood-brain barrier model in vitro was established and based on co-culture of HK-2, L-02 and SH-SY5Y, the idMOC model was established. The toxicity and toxic action characteristics of ACR on SH-SY5Y cells were evaluated by validation tests.


Assuntos
Acrilamida/toxicidade , Apoptose/efeitos dos fármacos , Barreira Hematoencefálica , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Linhagem Celular Tumoral , Técnicas de Cocultura , Humanos , Neurônios , Ratos
15.
Faraday Discuss ; 192: 197-216, 2016 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-27460155

RESUMO

CaCO3 calcination is an important step in calcium looping, and the formed pore structure of porous CaO is critical for subsequent carbonation towards carbon dioxide. Therefore, it is necessary to investigate the evolution of the pore structure of the sorbent in the calcination step. A mathematical model describing the pore size distribution during the calcination of the CaCO3 particle was developed. CaCO3 calcination is calculated following a shrinking core model at the CaO-CaCO3 interface, and CO2 diffuses through the porous CaO layers. During the decomposition of CaCO3, after the departure of the CO2 molecule from its original lattice, a vacancy will be formed that will diffuse inside the solid, and the collision and coagulation of the vacancy results in pore formation. A rate equation theory was proposed to describe the vacancy coagulation and pore evolution inside the solid, with rate expressions derived for the pore size distribution function with time evolution. To validate the developed model, the evolution of the pore size distribution during CaCO3 calcination was experimentally measured in a high-temperature furnace combined with the nitrogen adsorption method. It was found that there is a characteristic bimodal distribution for the pore structure of calcined CaCO3, with average pore sizes of ∼2.8 nm and ∼50 nm. The calculated results agree well with the experimental data, and the relative importance of growth and coagulation was discussed.

16.
Genet Mol Res ; 15(2)2016 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-27173214

RESUMO

Broccoli and cabbage are important vegetable crops that produce hybrid seeds after insect pollination; the size of floral organs is crucial for this process. To investigate the genetic characteristics of floral organ sizes (corolla width, petal length and width, and lengths of stamen, anther, style, and stigma) and to improve the flower size and breeding efficiency of broccoli, we used multi-generation analysis of a major gene plus polygene model. Six populations obtained from a broccoli inbred line 93219 (small floral organs) and cabbage inbred line 195 (large floral organs) were used for the analysis. Corolla and petal width and stamen and anther length were controlled by the additive-dominance-epistasis polygene model. The heritability of these traits in BC1, BC2, and F2 generations was high (72.80-93.76%). Petal and stigma length were governed by the two major genes of additive-dominance-epistasis effects plus additive-dominance polygene model; the major gene heritability in the F2 generation were 79.17 and 65.77%, respectively. Style length was controlled by one major gene of additive-dominance effects plus additive-dominance-epistasis polygene model; the major gene heritability in BC1, BC2, and F2 were 40.60, 10.35, and 38.44%, respectively; the polygene heritability varied from 41.85 to 68.44%. Our results provide important genetic information for breeding, which could guide improvement of flower-related traits and lay the foundation for quantitative trait loci mapping of the flower-size traits in Brassica.


Assuntos
Brassica/genética , Epistasia Genética , Hibridização Genética , Herança Multifatorial , Flores/anatomia & histologia , Flores/genética , Genes Dominantes , Genes de Plantas , Característica Quantitativa Herdável
17.
Br J Cancer ; 112(11): 1766-71, 2015 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-25942394

RESUMO

BACKGROUND: The tumour-node-metastasis (TNM) classification is the most widely used tool for penile cancer. However, the current system is based on few studies and has been unchanged since 2009. We determined whether a modified pathological N staging system that incorporates the laterality and number of lymph node metastases (LNMs) increases the accuracy of the results in predicting survival compared with the 7th edition of the pathological N staging system of the American Joint Committee on Cancer (AJCC) for penile cancer. METHODS: The clinical and histopathologic data from 111 patients with penile cancer with LNMs were analysed. Univariate and multivariate Cox proportional hazard regression analyses were used to determine the impact of the clinical and pathological factors on disease-specific survival of these patients. The predictive accuracy was further assessed using the concordance index. RESULTS: According to the 7th edition of the pathological N classification, the 3-year disease-specific survival (DSS) rates for patients with pN1, pN2, and pN3 disease are 89.6%, 65.9%, and 33.6%, respectively (P(N1-N2)=0.030, P(N2-N3)<0.001, P<0.001). Under the modified pathological N category criteria, the 3-year DSS rates for pN1, pN2, and pN3 patients were 90.7%, 60.5%, and 31.4%, respectively (P(N1-N2)=0.005, P(N2-N3)=0.004, P<0.001). In separate multivariate Cox regression models, only modified N stages (hazard ratio: 4.877, 10.895; P=0.018, P<0.001) exhibited independent effects on the outcome. The accuracy of the modified pathological N category was significantly increased. CONCLUSIONS: The modified pathological N staging system is a better reflection of the prognosis of patients with penile cancer. Our study should contribute to the improvement of prognostic stratification and systemic treatment to avoid overtreatment of patients.


Assuntos
Linfonodos/cirurgia , Segunda Neoplasia Primária/cirurgia , Neoplasias Penianas/cirurgia , Prognóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Linfonodos/patologia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Segunda Neoplasia Primária/patologia , Neoplasias Penianas/patologia , Modelos de Riscos Proporcionais , Resultado do Tratamento
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA