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1.
Huan Jing Ke Xue ; 44(10): 5813-5822, 2023 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-37827796

RESUMO

Soil acidification and low SOC are the main limiting factors in acidic paddy soils. Straw returning with lime is an effective measure to alleviate soil acidification and improve soil fertility; however, its interaction effects on SOC and carbon pool management are still unclear. To investigate the impact of straw returning with lime on the organic carbon pool of acidic paddy soil, field experiments were conducted on acidic paddy soil in Baiyun District and Huiyang District of Guangdong Province. The changes in soil total organic carbon (TOC), water-soluble organic carbon (DOC), active organic carbon (LOC), particulate organic carbon (POC), microbial biomass carbon (MBC), carbon pool index (CPI), stable organic carbon (IOC), carbon pool activity (L), carbon pool activity index (CPAI), and carbon pool management index (CPMI) were analyzed under three treatments (CK, conventional fertilization; RS, straw returning+conventional fertilization; RS+L straw returning with lime+conventional fertilization). The results demonstrated that compared with that in CK, the TOC, LOC, POC, and MBC in the RS+L treatment were significantly increased by 10.24%-17.79%, 34.49%-44.37%, 19.27%-23.59%, and 33.36%-43.26%, respectively (P<0.05). Compared with that in CK, the RS+L treatment significantly increased the DOC content during the early growth stage (15-45 days after transplanting) of rice (P<0.05) but had no significant influence on the DOC content during the late growth stage of rice. Compared with that in RS, the TOC, LOC, POC, and MBC in the RS+L treatment were increased by 2.15%-6.95%, 1.17%-17.90%, 4.27%-8.65%, and 12.99%-14.53%, respectively. Compared with that in CK, the RS+L treatment significantly increased IOC and CPI by 8.32%-15.57% and 14.00%-20.00%, respectively (P<0.05). Compared with that in the CK treatment, the RS treatment significantly increased CPI by 14.00%-18.00% (P<0.05). No significant differences in L, CPAI, or CPMI were detected among the different treatments. The soil pH in the RS+L treatment was significantly higher than that in the CK treatment (P<0.05). No significant differences in rice yield were detected among the different treatments. Principal component analysis demonstrated that rice yield was primarily correlated with DOC, LOC, CPAI, and CPMI but its contribution to SOC and carbon pool management index was low. Principal component analysis also indicated that straw returning with lime could improve soil pH and nutrient contents of acidic paddy soil, driving the formation and accumulation of organic carbon fraction such as MBC and POC, thus boosting the increase in SOC. In conclusion, straw returning with lime is beneficial to the accumulation of MBC, POC, LOC, and IOC in acidic paddy soil to improve the content and stability of soil total organic carbon, which is an effective way to improve the carbon sequestration of acidic paddy soil.

2.
Acta Pharmacol Sin ; 40(3): 410-417, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30202013

RESUMO

We recently reported that a CB2R agonist, GW405833 (GW), reduced both the ACh-induced Ca2+ oscillations and the L-arginine-induced Ca2+ signal enhancement in mouse pancreatic acinar cells, suggesting that GW-induced inhibition may prevent the pathogenesis of acute pancreatitis. In this study, we aim to evaluate the effects of other cannabinoid ligands on Ca2+ signaling in acinar cells. Patch-clamp whole-cell recordings were applied to measure ACh-induced intracellular Ca2+ oscillations in pancreatic acinar cells acutely dissociated from wild-type (WT), CB1R knockout (KO), and CB2R KO mice, and the pharmacological effects of various cannabinoid ligands on the Ca2+ oscillations were examined. We found that all the 8 CB2R agonists tested inhibited ACh-induced Ca2+ oscillations. Among them, GW, JWH133, and GP1a caused potent inhibition with IC50 values of 5.0, 6.7, and 1.2 µmol/L, respectively. In CB2R KO mice or in the presence of a CB2R antagonist (AM630), the inhibitory effects of these 3 CB2R agonists were abolished, suggesting that they acted through the CB2Rs. The CB1R agonist ACEA also induced inhibition of Ca2+ oscillations that existed in CB1R KO mice and in the presence of a CB1R antagonist (AM251), suggesting a non-CB1R effect. In WT, CB1R KO, and CB2R KO mice, a nonselective CBR agonist, WIN55,212-2, inhibited Ca2+ oscillations, which was not mediated by CB1Rs or CB2Rs. The endogenous cannabinoid substance, 2-arachidonoylglycerol (2-AG), did not show an inhibitory effect on Ca2+ oscillations. In conclusion, CB2R agonists play critical roles in modulating Ca2+ signals in mouse pancreatic acinar cells, while other cannabinoid ligands modulate Ca2+ oscillations in a heterogeneous manner through a CB receptor or non-CB-receptor mechanism.


Assuntos
Células Acinares/efeitos dos fármacos , Cálcio/metabolismo , Agonistas de Receptores de Canabinoides/farmacologia , Receptor CB1 de Canabinoide/agonistas , Receptor CB2 de Canabinoide/agonistas , Animais , Ligantes , Masculino , Camundongos Knockout , Pâncreas/citologia
3.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(4): 1170-4, 2016 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-30052340

RESUMO

The ICP in closed quartz chamber is an effective solution to local stealth of aircraft. The attenuation of the electromagnetic wave is strongly affected by distribution of electron density in incidence direction. In this paper, an experiment that the planar ICP discharged in all-quartz chamber (30.8 cm×30.8 cm×5.8 cm) was conducted. The E-H mode transition of Ar/Air ICP was observed, and the width and the proportion of ICP area versus the RF power were measured. Such physical phenomena were explained rationally by ICP-source theoretical model. A new microwave diagnostics is presented based on the Hß spectrum broadening and the characteristics of planar-coil ICP. It is used to diagnose the spatial electron density distribution of Ar/Air in incidence direction. The parameters of electron density distribution function in the incident direction are separately solved by the fitting results of the Hß stack broadening and microwave interferometer. And the curves of electron density distribution versus RF power are obtained. We obtain a stable ring plasma source with electron density varying from 0.5×1011~3.2×1011 cm-3. The experiment demonstrates that electron density is prominently affected by the RF power and gas species. The peak value of electron density is positioned near the center of ICP. It is shown that the electron density of Ar ICP is higher than the air, but the area of air ICP is larger through comparing the curves of Ar/Air electron density.

4.
Ying Yong Sheng Tai Xue Bao ; 27(12): 3913-3919, 2016 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-29704350

RESUMO

Based on the data of remote sensing images from Landsat in 1995 and 2015, this paper used the principal component analysis (PCA) method to determine the weights of four ecological indexes (greenness, dryness, wetness and heat), and then selected a evaluation model of remote sensing based ecological index (RSEI) to monitor and analyze the ecological environment quality of Weinan City from 1995 to 2015. The results showed that the mean values of RSEI in Weinan City increased from 0.489 to 0.556 during 1995-2015, which indicated the ecological environment qua-lity had been improved. The improved area of ecological quality was mainly distributed in the central area of Weinan City and its proportion was 49.6%. While the proportion of ecological environment degradation was 15.4%, and such areas were mainly distributed in some mine areas of Hancheng City and the southern Weinan (Weinan Section in North Qinling Mountains). The quality of ecolo-gical environment was greatly influenced by the urban planning and construction in the study area. Generally, the ecological condition of Weinan City had been improved, which benefited from the attention and investment of government.


Assuntos
Cidades , Monitoramento Ambiental , China , Planejamento de Cidades , Ecologia , Ecossistema , Modelos Teóricos , Tecnologia de Sensoriamento Remoto
5.
Zhonghua Yi Xue Za Zhi ; 87(37): 2657-9, 2007 Oct 09.
Artigo em Chinês | MEDLINE | ID: mdl-18162158

RESUMO

OBJECTIVE: To investigate the expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in allograft with chronic rejection (CR) after heart transplantation. METHODS: Seventy-two SD rats receiving transplantation of the heats of 71 Wistar rats were divided into 4 equal groups: Group A, undergoing heterotopic cervical heart transplantation (transplanted with donor's heart subcutaneously at the neck) and receiving none intervention, and with the transplanted hearts taken out 3 d after transplantation to the end of CR; Group B, injected intravenously with the splenocytes (SPCs) of the donors on day 0, injected with cyclophomide (CP) on d2, transplanted with the donor hearts on d15, with the transplanted hearts taken out 15 - 120 days after transplantation; Group C, transplanted with the donor's heart and injected intraperitoneally with cyclosporine A (Cs A) 10 mg/kg every other day for 8 - 10 times, and with the transplanted hearts taken out 60 d after transplantation to the end of CR; and Group D, injected intravenously with the SPCs of the donors on day 0, injected with CP on d2, transplanted with the donor hearts on d15, with the transplanted hearts taken out 150 - 420 days after transplantation. Immunohistochemical method was used to detect the expression of ICAM-1 and VCAM-1 in the allografts. RESULTS: The cardiac allograft survival time of Group B was the longest. Less ICAM-1 and VCAM-1 expression and lymphocyte infiltration were observed in SPC and CP-pretreated group. Reversely, protein expression levels of ICAM-1 and VCAM-1 were both high and significant lymphocyte infiltration was seen in Groups B and D. There was no significant difference in the expression of ICAM-1 and VCAM-1 between Groups A and C (P > 0.05). CONCLUSION: The expression levels of ICAM-1 and VCAM-1 are associated with the occurrence and development of rejection and have positive correlation with the severity of graft rejection. Determination of ICAM-1 and VCAM-1 can predict the function of allograft and provide evidence for early diagnosis and prevention of CR.


Assuntos
Rejeição de Enxerto/metabolismo , Transplante de Coração/métodos , Molécula 1 de Adesão Intercelular/biossíntese , Molécula 1 de Adesão de Célula Vascular/biossíntese , Animais , Imuno-Histoquímica , Ratos , Ratos Sprague-Dawley , Ratos Wistar , Transplante Homólogo
6.
Zhonghua Yi Xue Za Zhi ; 84(11): 888-90, 2004 Jun 02.
Artigo em Chinês | MEDLINE | ID: mdl-15329270

RESUMO

OBJECTIVE: To explore the effect of one-way valved patch used in congenital heart disease with severe pulmonary hypertension. METHODS: One-way valved patch was used in 30 patients of congenital heart disease with severe pulmonary hypertension (PP/PS > 0.75) in operation. Follow-up of 6 approximately 86 months was conducted to observe its effect. RESULTS: The pulmonary artery pressure was significantly decreased without trans-patch shunt in 11 cases postoperatively. Trans-patch shunt was determined in 27 cases within postperative 72 hours. There were 2 postoperative deaths out of these 27 patients: one died of low cardiac output syndrome 72 hours after operation, and the other died of right heart failure 4 weeks after operation. Thirty-six patients were restored to health and discharged. Three-month follow-up showed trans-patch shunt in 7 cases, including right-to left shunt in 4 cases and two-side shunt in other 3 cases. Color Doppler ultrasonography conducted 6 months after operation proved trans-patch shunt in 4 cases, right-to-left shunt in 1 case, two-side shunt in 2 cases, and left-to-right shunt in 1 case (PP/PS = 0.45). CONCLUSION: One-way valved patch is useful in selected patients in which postoperative right heart failure can be anticipated so as to shunt the blood in the right heart to the left heart and increase the blood volume in the left heart system to ensure the left heart output and minimize the risk of postoperative right heart failure, at the expense of systemic low oxygen saturation that is, however, well tolerated.


Assuntos
Defeitos dos Septos Cardíacos/cirurgia , Hipertensão Pulmonar/cirurgia , Próteses e Implantes , Adolescente , Adulto , Procedimentos Cirúrgicos Cardíacos/métodos , Criança , Pré-Escolar , Feminino , Seguimentos , Comunicação Interatrial/cirurgia , Comunicação Interventricular/cirurgia , Humanos , Hipertensão Pulmonar/etiologia , Masculino , Pessoa de Meia-Idade , Insuficiência da Valva Pulmonar/etiologia
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