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1.
Ying Yong Sheng Tai Xue Bao ; 30(10): 3356-3366, 2019 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-31621221

RESUMO

To reveal the seedlings dynamics of dominant trees and their response to canopy changes (as indicated by changes in leaf area index), we analyzed the seedlings dynamics of dominant trees and canopy structure during forest regeneration based on three-year (2014 to 2016) censuses and hemispherical photography in a 4 hm2 forest dynamics monitoring plot. The results showed that canopy LAI first decreased and then increased during the survey period, with significant interannual difference. The seedlings of 12 dominant tree species showed notable response to the change of canopy structure, with the response varying among different tree species. The relative abundance or frequency of seedlings for neutral tree species generally increased with the decreases of canopy LAI. The relative abundance or frequency of seedlings of light-demanding tree species generally decreased with the increases of canopy LAI. In multi-response permutation procedures by analyzing the numeric composition and distribution of dominant tree seedlings, there was significant difference among the three censuses. Such interannual difference gradually decreased from 2014 to 2016. Significant change occurred in the indicator species of dominant tree seedlings, reflecting their responses to the changes of canopy structure.


Assuntos
Plântula , Árvores , China , Florestas , Folhas de Planta
2.
Chin J Nat Med ; 16(10): 774-781, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30322611

RESUMO

A series of berberine derivatives were synthesized by introducing substituted benzyl groups at C-9. All these synthesized compounds (4a-4m) were screened for their in vitro antibacterial activity against four Gram-positive bacteria and four Gram-negative bacteria and evaluated for their antifungal activity against three pathogenic fungal strains. All these compounds displayed good antibacterial and antifungal activities, compared to reference drugs including Ciprofloxacin and Fluconazole; Compounds 4f, 4g, and 4l showed the highest antibacterial and antifungal activities. Moreover, all the synthesized compounds were docked into topoisomerase II-DNA complex, which is a crucial drug target for the treatment of microbial infections. Docking results showed that H-bond, π-π stacked, π-cationic, and π-anionic interactions were responsible for the strong binding of the compounds with the target protein-DNA complex.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Antifúngicos/química , Antifúngicos/farmacologia , Berberina/química , Berberina/farmacologia , Antibacterianos/síntese química , Antifúngicos/síntese química , Bactérias/efeitos dos fármacos , Berberina/síntese química , Desenho de Fármacos , Fungos/efeitos dos fármacos , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade
3.
Curr Med Sci ; 38(2): 268-276, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30074185

RESUMO

The relationship between the levels of renalase and changes in proteinuria, hypertension, renal function, renal tubular epithelial cell apoptosis and B-cell lymphoma-2 (Bcl-2) expression was investigated in patients (chronic nephritis, primary nephrotic syndrome or other kidney disease) that underwent renal biopsy. The study group comprised 72 patients undergoing renal biopsy. Patient profiles and renal function were collected. Concentrations of renalase and Bcl-2 were measured by immunohistochemistry. Tubular injury was detected by periodic acid Schiff staining (PAS) and renal tubular epithelial cell apoptosis was assessed by TUNEL assay. The expression of renalase was significantly lower in renal biopsy specimens than in normal kidney tissues. There was a positive linear relationship between renalase and some serum and cardiac indices; a negative correlation was found between age, eGFR, Ccr and 24-h urinary protein. Renal tubule injury index and tubular epithelial cell apoptosis index showed a negative linear correlation with renalase. The results showed that renalase probably increased the expression of Bcl-2. By two independent samples t-test, renalase levels were significantly increased in the non-hypertension group than in the hypertension group. One-way ANOVA showed that renalase expression was higher in samples with Lee's grade III than in those with Lee's grade V. The expression of renalase was significantly decreased in patients who underwent renal biopsy, and was also associated with blood and renal function. The research proved that renalase may reduce renal tubular injury and apoptosis of renal tubular epithelial cells through the mitochondrial apoptosis pathway, finally achieving the purpose of delaying the progress of renal failure.


Assuntos
Nefropatias/enzimologia , Rim/enzimologia , Rim/patologia , Monoaminoxidase/metabolismo , Adulto , Apoptose , Biópsia , Células Epiteliais/enzimologia , Células Epiteliais/patologia , Feminino , Humanos , Hipertensão/complicações , Imunoglobulina A/metabolismo , Rim/cirurgia , Nefropatias/complicações , Nefropatias/patologia , Nefropatias/cirurgia , Túbulos Renais/patologia , Masculino , Nefrectomia
4.
Ying Yong Sheng Tai Xue Bao ; 29(1): 18-24, 2018 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-29692008

RESUMO

We established a 4 hm2(200 m×200 m) temperate secondary forest plot in the montane region of eastern Liaoning Province, China, and analyzed the spatial patterns and interspecific spatial associations of tree seedlings at scales of 0-50 m. The results showed that under complete spatial randomness null model, 95% of the species at the scale of 0-20 m showed a significant aggregation pattern, and 19 species at the scale of 0-16 m showed an aggregation pattern. The proportion of species exhibiting aggregated patterns decreased with the spatial scale. At the scale of 50 m, the random distribution pattern became the main form of tree species distribution. Underheterogeneous Poisson process null model, 5% of the species at the scale of 0-24 m showed a significant aggregation pattern, and 42% and 58% of the species at the scale of 26-50 m showed a random distribution and regularity patterns, respectively. Under complete spatial randomness null model, the proportion of species pairs of positive correlation was the highest, and at the scale of 50 m, the proportion of species pairs showed positive correlation, uncorrelated and negative correlation tended to be equal. Under heterogeneous Poisson process null model, species pairs mainly showed negative correlation, and the proportion of species pairs exhibiting negative correlation increased with spatial scale. The results implied that seed dispersal limitation and habitat heterogeneity could explain the aggregation pattern of tree seedlings. The strong aggregation of tree seedlings also contributed to close interspecific spatial associations and poor stability of the regeneration community.


Assuntos
Florestas , Plântula/crescimento & desenvolvimento , China , Ecossistema , Árvores
5.
Adv Mater ; 30(23): e1707483, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29659055

RESUMO

Organic frameworks represent an emerging family of advanced materials that can be precisely controlled at the atomic level. However, morphology control of organic frameworks remains perplexing and difficult, strongly limiting the advantages of organic frameworks in multiple practical applications. Herein, porphyrin organic framework hollow spheres (POF-HSs) are fabricated by a template method as a proof of concept of organic frameworks with precisely controlled morphology. POF-HS exhibits explicit chemical structures of 2D POF and an expected hollow structure. The morphology of POF-HS is further regulated in terms of void size and shell thickness. Benefited from the polar chemical structures and the hollow spherical morphology, POF-HS sufficiently mitigates the shuttle of polysulfides by taking the dual effects of chemical adsorption and physical confinement and functions as a desirable host material for sulfur cathode to endow lithium-sulfur batteries with high capacity, long cycling life, and excellent rate performance. The accurate synthesis of POF-HSs demonstrates the highly controllable and versatile morphology of organic framework materials beyond precise integration of organic building blocks and represents infinite possibility of offering exotic organic frameworks for chemistry, sustainable energy, and material science.

6.
Small ; 13(25)2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28508560

RESUMO

The construction of active sites with intrinsic oxygen evolution reaction (OER) is of great significance to overcome the limited efficiency of abundant sustainable energy devices such as fuel cells, rechargeable metal-air batteries, and in water splitting. Anionic regulation of electrocatalysts by modulating the electronic structure of active sites significantly promotes OER performance. To prove the concept, NiFeS electrocatalysts are fabricated with gradual variation of atomic ratio of S:O. With the rise of S content, the overpotential for water oxidation exhibits a volcano plot under anionic regulation. The optimized NiFeS-2 electrocatalyst under anionic regulation possesses the lowest OER overpotential of 286 mV at 10 mA cm-2 and the fastest kinetics being 56.3 mV dec-1 to date. The anionic regulation methodology not only serves as an effective strategy to construct superb OER electrocatalysts, but also enlightens a new point of view for the in-depth understanding of electrocatalysis at the electronic and atomic level.

7.
Zhongguo Zhong Yao Za Zhi ; 41(4): 755-759, 2016 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-28871706

RESUMO

With the enhancement in the awareness of self-diagnosis among residents, it's very common for each family to prepare common medicines for unexpected needs. Meanwhile, with the popularization of the traditional Chinese medicine knowledge, the proportion of common traditional Chinese medicines prepared at residents' families is increasingly higher than western medicines year by year. To make it clear, both pre-research and closed questionnaire research were adopted for residents in Chaoyang District, Beijing, excluding residents with a medical background. Based on the results of data, a analysis was made to define the role and influence on the quality of life of residents and give suggestions for relevant departments to improve the traditional Chinese medicine popularization and promote the traditional Chinese medicine market.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Medicina Tradicional Chinesa/estatística & dados numéricos , Adolescente , Adulto , Idoso , China , Medicamentos de Ervas Chinesas/economia , Família , Feminino , Humanos , Masculino , Medicina Tradicional Chinesa/economia , Pessoa de Meia-Idade , Inquéritos e Questionários , Adulto Jovem
8.
Zhongguo Zhen Jiu ; 29(9): 695-8, 2009 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-19803233

RESUMO

OBJECTIVE: To observe the therapeutic effect of acupoint sticking therapy for treatment of stroke. METHODS: Two hundred and forty-six cases were randomly divided into a non-acupoint sticking group (control group, n=122) and an acupoint sticking group (n=124). The control group was treated with routine ward treatment of stroke (acupuncture combined with routine western medicine). The acupoint sticking group was treated with basis ward treatment of stroke (similar to the control group), and acupoint sticking therapy was applicated on Shenque (CV 8). The scores of Stroke-Specific Quality of Life (SS-QOL) and WHOQOL-100BREF were adopted to evaluate the therapeutic effects and the cysteine of patients were tested before and after treatment. RESULTS: There were significant differences in scores comparison of SS-QOL and WHOQOL-100BREF before and after treatment in both groups (both P < 0.001); there was no significant difference after treatment between two groups (P > 0.05); there was a significant difference in thinking items of SS-QOL after treatment between two groups (P < 0.05), the acupoint sticking group was superior to that of control group; SS-QOL score of patients with abnormal cysteine of acupoint sticking group was superior to that of the control group after treatment, with a significant difference between the two groups (P < 0.05). CONCLUSION: The acupoint sticking therapy can improve the thinking ability of stroke patients, and improve the life quality of high cysteine stroke patients.


Assuntos
Pontos de Acupuntura , Terapia por Acupuntura , Acidente Vascular Cerebral/terapia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Acidente Vascular Cerebral/psicologia , Pensamento
9.
Macromol Rapid Commun ; 30(7): 532-8, 2009 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21706637

RESUMO

Well-defined polymethylene-block-polystyrene (PM-b-PS) diblock copolymers were synthesized via a combination of living polymerization of ylides and atom transfer radical polymerization (ATRP) of styrene. A series of hydroxyl-terminated polymethylenes (PM-OHs) with different molecular weight and narrow molecular weight distribution were prepared using living polymerization of ylides following efficient oxidation in a quantitive functionality. Then, the macroinitiators (PM-MIs ($\overline M _{\rm n}$ = 1 900-15 000; PDI = 1.12-1.23)) transformed from PM-OHs in ≈ 100% conversion initiated ATRPs of styrene to construct PM-b-PS copolymers. The GPC traces indicated the successful extension of PS segment ($\overline M _{\rm n}$ of PM-b-PS = 5 000-41 800; PDI = 1.08-1.23). Such copolymers were characterized by (1) H NMR and DSC.

10.
Zhongguo Zhen Jiu ; 26(12): 899-903, 2006 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-17313017

RESUMO

OBJECTIVE: To summarize clinical application of acupoint sticking therapy in various fields of Chinese medicine. METHODS: Review acupoint selection, drug selection and problems of clinical studies in acupoint sticking therapy. CONCLUSION: Acupoint sticking therapy has a good therapeutic effect with no adverse effect, safety and convenient manipulation.


Assuntos
Pontos de Acupuntura , Terapia por Acupuntura/métodos , Humanos
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