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1.
Zhongguo Zhen Jiu ; 43(11): 1257-1260, 2023 Sep 08.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-37986248

RESUMO

OBJECTIVES: To observe the clinical effect of wrist-ankle acupuncture on postpartum abdominal pain and its influence on serum beta-endorphin (ß-EP) level in puerpera. METHODS: Seventy patients with postpartum abdominal pain were randomly divided into an acupuncture + herbal medication group (35 cases, 1 case dropped out) and a herbal medication group (35 cases, 2 cases dropped out). In the herbal medication group, 1 day after delivery, modified shenghua decoction was taken orally, one dose a day. In the acupuncture + herbal medication group, on the basis of herbal medication, wrist-ankle acupuncture was given at the Lower 1 and Lower 2 of the ankles, once daily. The duration of treatment was 3 days in the two groups. Before and after treatment, the score of visual analogue scale (VAS) for pain, serum ß-EP level, uterine fundus height, postpartum conditions of lochia and the uterine recovery at 42 days postpartum were compared in the patients of the two groups. RESULTS: At each time point after treatment (24 h, 48 h and 72 h after delivery), VAS scores and the uterine fundus height were reduced as compared with those before treatment (2 h after delivery) in the two groups (P<0.05); these indexes in the acupuncture + herbal medication group were lower than those in the herbal medication group (P<0.05). After treatment (72 h after delivery), ß-EP levels in the serum were increased when compared with those before treatment in the two groups (P<0.05), and the ß-EP level in the acupuncture + herbal medication group was higher than that in the herbal medication group (P<0.05). The volume of postpartum lochia discharge in the acupuncture + herbal medication group was higher than that in the herbal medication group (P<0.05), while the duration of postpartum lochia discharge and the total time of lochia discharge were shorter (P<0.05). Regarding the recovery of the uterus at 42 days postpartum, there was no statistical significance between the two groups (P>0.05). CONCLUSIONS: Wrist-ankle acupuncture obviously reduces the degree of postpartum abdominal pain and promotes the lochia discharge and the uterine recovery. The effect mechanism may be related to the up-regulation of serum ß-EP level and the increase of pain threshold so that analgesia is obtained.


Assuntos
Terapia por Acupuntura , Tornozelo , Feminino , Humanos , beta-Endorfina , Punho , Dor Abdominal , Pontos de Acupuntura
2.
Org Lett ; 24(43): 7934-7938, 2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36268997

RESUMO

Reaction of 2,3-allenols with PhMe2SiZnCl or Ph2MeSiZnCl under catalysis of IPrCuCl or SIPrCuCl was carried out, affording 2-silyl-1,3-butadienes. Secondary and tertiary 2,3-allenols could be used as coupling partners. Reaction of secondary 2,3-allenols gave (E)-2-silyl-1,3-butadienes as the only products.

3.
Org Lett ; 24(2): 692-696, 2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35057630

RESUMO

Regioselective silylation of 2,3-allenols with disilanes was carried out under catalysis of Pd2dba3/P(o-MeOC6H4)3. In the presence of Cs2CO3, the reaction achieved 2-silyl-1,3-dienes. Reaction of 1-aryl-2,3-allenols gave the products with excellent Z/E selectivity and E-isomers as the major species. Reaction of α-alkylallenols or α-alkyl-α-aryl-allenols resulted in products with moderate Z/E selectivity and E-isomers are also major. Without a base, the reaction produced α-silyl-ß-hydroxyl vinylsilanes, which were converted to 2-silyl-1,3-dienes upon treatment with Cs2CO3.

4.
J Am Chem Soc ; 143(12): 4536-4542, 2021 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-33724807

RESUMO

The regiocontrolled functionalization of 1,3-dienes has become a powerful tool for divergent synthesis, yet it remains a long-standing challenge for aliphatic substrates. Herein, we report a reductive approach for a branch-selective 1,2-hydrovinylation of aliphatic 1,3-dienes with R-X electrophiles, which represents a new selectivity pattern for diene functionalization. Simple butadiene, aromatic 1,3-dienes, and highly conjugated polyene were also tolerated. The combination of Ni(0) and the phosphine-nitrile ligand generally resulted in >20:1 regioselectivity with the retention of the geometry of the C3-C4 double bonds. This reaction proceeds with a broad substrate scope, and it allows for the conjugation of two biologically active units to form more complex polyene molecules, such as tetraene and pentaene as well as heptaene.

5.
Angew Chem Int Ed Engl ; 59(51): 23083-23088, 2020 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-32902100

RESUMO

The cross-electrophile coupling has become a powerful tool for C-C bond formation, but its potential for forging the C-Si bond remains unexplored. Here we report a cross-electrophile Csp2 -Si coupling reaction of vinyl/aryl electrophiles with vinyl chlorosilanes. This new protocol offers an approach for facile and precise synthesis of organosilanes with high molecular diversity and complexity from readily available materials. The reaction proceeds under mild and non-basic conditions, demonstrating a high step economy, broad substrate scope, wide functionality tolerance, and easy scalability. The synthetic utility of the method is shown by its efficient accessing of silicon bioisosteres, the design of new BCB-monomers, and studies on the Hiyama cross-coupling of vinylsilane products.

6.
Artigo em Inglês | MEDLINE | ID: mdl-32722539

RESUMO

This study experimentally investigated heavy metal removal and accumulation in the aquatic plant Eichhornia crassipes. Pb, Zn, Cd, and Mn concentrations, plant morphology, and plant functional groups were analyzed. Eichhornia crassipes achieved high removal efficiency of Pb and Mn from karst water (over 79.5%), with high proportion of Pb, Zn, and Cd absorption occurring in the first eight days. The highest removal efficiencies were obtained at initial Pb, Zn, Cd, and Mn concentrations of 1 mg/L, 2 mg/L, 0.02 mg/L, and 0.2 mg/L, respectively. Eichhornia crassipes exhibited a high bioconcentration factor (Mn = 199,567 > Pb = 19,605 > Cd = 3403 > Zn = 1913) and a low translocation factor (<1). The roots accumulated more Pb, Zn, Cd, and Mn than the stolons and leaves due to the stronger tolerance of roots. The voids, stomas, air chambers, and airways promoted this accumulation. Pb, Cd, Zn, and Mn likely exchanged with Mg, Na, and K through the cation exchange. C≡C, C=O, SO42-, O-H, C-H, and C-O played different roles during uptake, which led to different removal and accumulation effects.


Assuntos
Eichhornia/metabolismo , Monitoramento Ambiental/métodos , Metais Pesados/análise , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Biodegradação Ambiental , Cádmio , Chumbo , Água , Zinco
7.
Artigo em Inglês | MEDLINE | ID: mdl-32024317

RESUMO

Karst water is rich in calcium ions (Ca2+) and exhibits poor metal availability and low biodegradation efficiency. This study sought to analyze the effects and mechanisms of Ca2+ on lead (Pb) removal and absorption by Eichhornia crassipes (a floating plant common in karst areas). Moreover, the morphology and functional groups of E. crassipes in water were characterized via SEM, and FTIR. The results demonstrated that the removal rate of Pb in karst water (85.31%) was higher than that in non-karst water (77.04%); however, the Pb bioconcentration amount (BCA) in E. crassipes roots in karst water (1763 mg/kg) was lower than that in non-karst water (2143 mg/kg). With increased Ca2+ concentrations (60, 80, and 100 mg/L) in karst water, the Pb removal rate increased (85.31%, 88.87%, and 92.44%), the Pb BCA decreased (1763, 1317, and 1095 mg/kg), and the Ca BCA increased (6801, 6955, and 9368 mg/kg), which was attributed to PbCO3 and PbSO4 precipitation and competitive Ca and Pb absorption. High Ca2+ concentrations increased the strength of cation exchange, alleviated the fracture degree of fibrous roots, reduced the atrophy of vascular bundles, protected the cell wall, promoted C-O combined with Pb, enhanced the strength of O‒H, SO42-, C=O, and reduced the oxidization of alkynyl acetylene bonds.


Assuntos
Cálcio/química , Eichhornia/metabolismo , Chumbo/metabolismo , Poluentes Químicos da Água/metabolismo , Biodegradação Ambiental , Chumbo/química , Poluentes Químicos da Água/química
8.
Huan Jing Ke Xue ; 40(6): 2675-2685, 2019 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854659

RESUMO

To investigate the environmental quality and human health risks of different types of groundwater at Xiangshui, Chongzuo, several regular water quality indexes and concentrations of metals in 60 groundwater samples were measured and analyzed. The environmental quality of groundwater was analyzed by means of the Nemerow index. The health risks were assessed by using a human health risk assessment model. The regular water quality indexes and concentrations of metals of the well water, spring water, and underground river water exceeded the standards to different degrees. The environmental quality of groundwater was at a poor grade. The comprehensive evaluation score of underground river water (F=4.26) was the lowest. The well water had the same score as spring water (F=7.10). The high hardness and salinity were conducive to enrichment of Cr, and the reducing environment was of great advantage for the enrichment of As. The environmental geochemistry of Zn, Pb, Cd, and Cu was similar. The sources of Fe, Al, and Mn were similar. The results of the health risk assessment indicated that the health risks of well water, spring water, and underground river water were relatively high. The health risks decreased in the order of well water > underground river water > spring water. The health risks mainly came from the carcinogenic metallic element Cr. Carcinogenic risks were 4-6 orders of magnitude higher than non-carcinogenic risks. Carcinogenic risks were higher than the maximum allowance levels (5.0×10-5 a-1). Non-carcinogenic risks were lower than the allowance levels (10-6 a-1). Children had greater health risks than adults. The health risks of metals through the drinking pathway were 2-3 orders of magnitude higher than the values caused by the dermal contact pathway. For the sake of drinking water safety, the well water, underground river water, and spring water should be properly treated and the concentration of Cr in groundwater should be controlled before drinking.


Assuntos
Água Subterrânea/análise , Metais Pesados/análise , Medição de Risco , Poluentes Químicos da Água/análise , Qualidade da Água , Adulto , Criança , China , Água Potável/análise , Monitoramento Ambiental , Humanos
9.
Huan Jing Ke Xue ; 40(5): 2143-2151, 2019 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-31087850

RESUMO

To investigate the major ionic characteristics, seasonal variation, and controlling factors of karst groundwater at Xiangshui, Chongzuo, 210 groundwater samples were collected and measured in wet season, dry season, and flat season in 2016. The controlling factors of karst groundwater were analyzed by using multivariate statistical analysis method. The results showed that the groundwater samples were weakly alkaline fresh water and rich in Ca2+ and HCO3-, which accounted for more than 75% and 70% of total ion concentration. The average concentrations of K+, Na+, Cl-, and NO3- decreased in the order of wet season > flat season > dry season. None of the concentrations of Ca2+, Mg2+, HCO3-, SO42-, pH, TDS, TZ+, and TZ- showed significant seasonal variation. The hydrochemical characteristics were found to be of HCO3-Ca type and mainly determined by carbonate rock dissolution. Only a small proportion of them were of HCO3·Cl-Ca and HCO3·SO4-Ca type in wet season and flat season, Cl·NO3-Ca type appeared in flat season, and HCO3-Ca·Mg type appeared in dry season, reflecting the influence of dolomite and ferric mudstone dissolution in the stratum, and of NO3- and Cl- input from anthropogenic activities. Groundwater Ca2+ and HCO3- mainly came from limestone dissolution; Na+, Cl-, K+, and NO3- came from atmospheric precipitation and human activities; while Mg2+ and SO42- came from dolomite and ferric mudstone dissolution. The chemical composition of groundwater was controlled by water-rock interaction, the groundwater in the carbonate aquifer was controlled by carbonate rocks dissolution, and the groundwater in villages and densely populated areas was affected by atmospheric precipitation and human activity.

10.
J Am Chem Soc ; 141(18): 7637-7643, 2019 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-31002758

RESUMO

Enantioselective cross-electrophile reactions remain a challenging subject in metal catalysis, and with respect to data, studies have mainly focused on stereoconvergent reactions of racemic alkyl electrophiles. Here, we report an enantioselective cross-electrophile aryl-alkenylation reaction of unactivated alkenes. This method provides access to a number of biologically important chiral molecules such as dihydrobenzofurans, indolines, and indanes. The incorporated alkenyl group is suitable for further reactions that can lead to an increase in molecular diversity and complexity. The reaction proceeds under mild conditions at room temperature, and an easily accessible chiral pyrox ligand is used to afford products with high enantioselectivity. The synthetic utility of this method is demonstrated by enabling the modification of complex molecules such as peptides, indometacin, and steroids.

11.
IEEE Trans Neural Netw Learn Syst ; 29(10): 4672-4682, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29990206

RESUMO

The stability property of delayed neural networks (NNs) along the whole delay axis is studied in this paper. Such a complete stability problem with respect to the delay parameter has not been addressed in the community of NNs. Most of the existing studies focus on the stability interval of delay starting from zero and are not applicable for the complete stability problem. In this paper, we will present some examples to show that there are various types of stability intervals for NNs, demonstrating the necessity of the complete stability analysis. We will adopt a frequency-sweeping approach to study delayed NNs in this paper. As a result, the complete stability problem with respect to delay for NNs can be systematically solved. The approach is applicable in the general case and simple to implement. Finally, some representative examples illustrate the approach.

12.
Clin Lab ; 64(6): 1037-1040, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29945322

RESUMO

BACKGROUND: To study the clinical effect of low molecular heparin on unexplained recurrent spontaneous abortion (URSA). METHODS: A total of 120 URSA patients were collected in our hospital from October 2015 to September 2017. They were divided into two groups: control group (n = 60) and observation group (n = 60). The patients in the control group were administered with progesterone and human chorionic gonadotropin, and the observation group with low molecular heparin. Pregnancy outcomes, incidence of complications in pregnancy and adverse drug reactions were compared in the two groups. RESULTS: The pregnancy success rate of patients in the observation group (90.00%) is higher than that in the control group (68.33%) (p < 0.05). The incidence of complications in pregnancy in the observation group (90.00%) is lower than those in the control group (68.33%) (p < 0.05). The incidence of adverse drug reactions between the patients in the observation group (20.00%) and those in the control group (23.33%) showed no significant difference (p > 0.05). CONCLUSIONS: Low molecular heparin treatment can improve pregnancy success rate and reduce the incidence of complications in the URSA patients. Low molecular heparin is characterized by safety and reliability and has potential for application in clinic.


Assuntos
Aborto Habitual/prevenção & controle , Aborto Espontâneo/prevenção & controle , Heparina de Baixo Peso Molecular/administração & dosagem , Resultado da Gravidez , Adulto , Gonadotropina Coriônica/administração & dosagem , Feminino , Humanos , Gravidez , Progesterona/administração & dosagem , Resultado do Tratamento
13.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-705313

RESUMO

Flavonoids are a large family of bioactive compounds widely found in foods and plants. Mang studies have proven the preventive and therapeutic effects of flavonoids in cardiovascular disease.Flavonoids has a wide range of pharmacological effects,including antioxidant,anti-inflammatory,vaso-dilation,avoiding the thrombus formation,improving endothelial function,modifying lipid levels and regulating blood lipids through different mechanisms of action.The cardiovascular protective mechanism of flavo-noids are the enzymes that inhibit the production of oxygen derived free radicals,inhibition of lipid peroxida-tion and inflammatory factor, down-regulation of epoxy synthase activity and the activation of AMPK and nuclear factor kappa B signaling pathway. In this review article we review and summarize the so far acquired knowledge of the most important mechanisms of action of flavonoids,to provide theoretical basis for the research and development of the active monomers in flavonoid and compound preparations.

14.
Chinese Pharmacological Bulletin ; (12): 741-744, 2018.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-705118

RESUMO

Flavonoids are a large class of bioactive compounds widely found in food and plants. Studies have found that they have a good preventive and therapeutic effect on cardiovascular diseases. Flavonoids have a wide range of pharmacological effects, including antioxidation, anti-inflammation, vasodila-tion, inhibiting platelet aggregation and regulating blood lipids and so on. The cardiovascular protective mechanism of fla-vonoids involves the enzymes that inhibit the production of oxy-gen derived free radicals, inhibition of lipid peroxidation and in-flammatory factor, down-regulation of epoxy synthase activity and activation of AMPK and nuclear factor kappa B signaling pathway. In this review we summarize the so far acquired knowl-edge of the most important mechanisms of flavonoid action, so as to provide the theoretical basis for the research and development of the active monomers in flavonoid and compound preparations.

15.
Zhongguo Zhen Jiu ; 29(12): 955-8, 2009 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-20088412

RESUMO

OBJECTIVE: To compare the clinical effects between electroacupuncture at Zusanli (ST 36) combined with intravenous drip of Granisetron and intravenous drip of Granisetron only for treatment of nausea and vomiting caused by the chemotherapy of the malignant tumor. METHODS: The methods of multicentral, randomized controlled trial were used, the observation group (127 cases) was treated with electroacupuncture at Zusanli (ST 36) combined with intravenous drip of Granisetron, and the control group (119 cases) was treated with intravenous drip of Granisetron only. RESULTS: The total effective rate of 90.5% in observation group was superior to that of 84.0% in control group (P < 0.01); the nausea and vomiting scores of two groups were obviously decreased after treatment (both P < 0.001), and the decreased degree of the observation group was superior to that of control group (P < 0.001). CONCLUSION: Electroacupuncture at Zusanli (ST 36) can significantly alleviate the symptoms such as nausea and vomiting caused by the chemotherapy of the patients.


Assuntos
Pontos de Acupuntura , Antineoplásicos/efeitos adversos , Eletroacupuntura , Náusea/terapia , Neoplasias/tratamento farmacológico , Vômito/terapia , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Náusea/etiologia , Neoplasias/complicações , Neoplasias/patologia , Vômito/etiologia , Adulto Jovem
16.
Zhonghua Yu Fang Yi Xue Za Zhi ; 42(5): 321-3, 2008 May.
Artigo em Chinês | MEDLINE | ID: mdl-18844080

RESUMO

OBJECTIVE: To describe the prevalence trend and epidemiological characteristics of neural tube defects (NTDs) in perinatal in Zhengzhou city from 1996 to 2005. METHODS: Data collected from hospital were used to depict the epidemiology of NTDs in Zhengzhou. All perinatal fetuses born in hospitals had an access within 7 days after delivery. The prevalence were calculated by perinatal'year, sex, birth area (urban versus rural) and maternal age. All monitored perinatal (162,074) accounted for 32.66% from totals (496,203). RESULTS: All 238 cases were found NTDs, and the overall prevalence rate was 14.68/10,000. The annual prevalence rate presented a decreasing trend during that period. The rates in rural and urban area, in male and female birth were 29.28/10,000 and 9.63/10,000, 11.42/10,000 and 17.74/10,000 respectively. There were significant differences among maternal-age-specific prevalence rates (chi2 = 22.952, P = 0.000). The rates of <20 years group(53.76/10,000) and >35 years group(21.74/10,000) were higher than others. CONCLUSION: The prevalence rates of NTDs in rural area is higher than that in urban, female's is higher than male's in Zhengzhou. The annual prevalence rates of NTDs presents a decreasing trend in the past ten years.


Assuntos
Defeitos do Tubo Neural/epidemiologia , China/epidemiologia , Feminino , Humanos , Recém-Nascido , Masculino , Gravidez , Segundo Trimestre da Gravidez , Terceiro Trimestre da Gravidez , Prevalência , População Rural , Distribuição por Sexo , População Urbana
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