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1.
Zhonghua Yan Ke Za Zhi ; 55(8): 576-581, 2019 Aug 11.
Artigo em Zh | MEDLINE | ID: mdl-31422635

RESUMO

Objective: To investigate the methods of optometric refraction adopted for adolescents in spectacles stores in Anyang city of Henan Province and the professional performance of optometric refraction. Methods: Cross-sectional study. Maps and yellow pages were used to collect the information of 131 spectacles stores in Anyang city. A questionnaire was used to investigate spectacles stores that had optometry equipment and can provide refraction prescription and spectacles in this city. The questionnaire covered (1) the process of optometric refraction, including whether cycloplegic refraction was conducted for adolescents and children if it was their first-time optometry and the type of cycloplegics,and (2) the opticians' knowledge on optometric refraction for adolescents and children, such as necessity of cycloplegic refraction for adolescents and children and age cut-offs. According to whether they used a comprehensive refractometer, the optometry methods were divided into conventional optometry and medical optometry. Results: Of 131 spectacles stores in Anyang city, 127 were enrolled. A total of 127 questionnaires were distributed and returned with an effective rate of 100%. Conventional optometric refraction was performed in 53 stores (41.73%), and medical optometric refraction was performed in 74 stores (58.27%). Cycloplegic refraction was conducted in only 4 spectacles stores (3.15%) for adolescents and children upon their first-time optometry. The fogging method of refraction was adopted in 31 stores (24.41%), while optometric refraction was directly conducted in 92 stores (72.44%) without controlling accommodation. As for the use of cycloplegia at initial optometric refraction of children, cycloplegia was objected to in 4 stores,and thought to be no need in 28 stores including 6 stores in which the fogging method was used to replace cycloplegia. In 68 stores, cycloplegia was performed if wanted, or children could go to a hospital for it. In 12 stores, the use of cycloplegics was determined by children's vision and diopters. In 5 stores, children were suggested to go to a hospital for cycloplegic refraction. Cycloplegic refraction was required in only 4 stores. As to the age cut-offs of cycloplegic refraction, 6 years old, 12 years old, and 18 years old were considered as the boundary in 7 stores, 33 stores, and 9 stores, respectively.In 11 stores, age was only considered for amblyopia and hyperopia, and in 67 stores, it was not realized. Conclusions: Cycloplegic refraction was found to be conducted for adolescents and children in only 3% of the spectacles stores in Anyang city. Moreover, most of the spectacles store opticians did not support to use cycloplegia before optometric refraction for adolescents and children and lacked knowledge on the age cut-offs of cycloplegic refraction.Standardized training of cycloplegic refraction should be further strengthened. (Chin J Ophthalmol, 2019, 55: 576-581).


Assuntos
Optometria , Refração Ocular , Erros de Refração , Adolescente , Criança , Estudos Transversais , Óculos , Humanos , Midriáticos
2.
RSC Adv ; 8(2): 1124-1131, 2018 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-35538968

RESUMO

Fading and showing mechanisms of ancient color paintings based on light scattering induced by particles were proposed. To confirm the mechanisms, simulated and application experiments were carried out to restore an ancient blurred color painting. Loading TiO2 particles (500-1000 nm) onto a piece of colored paper could result in blurring of the color of the paper, which is attributed to light scattering caused by air voids between the particles. Filling air voids with ionic liquid (a non-volatile solution with a high refractive index) could highlight the color by reducing scattering. These results were experimentally testified by the combination of a fluorescence probe and multi-angle reflectance spectra, in which scattering decreased the incident optical path in the painting layer while the incident optical path was increased by filling the air voids with ionic liquid. As a practical example, the proposed method was applied to highlight an ancient Chinese painting with blurred color. This investigation is very useful to restore faded color paintings.

3.
Mini Rev Med Chem ; 5(1): 1-12, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15638787

RESUMO

Structure activity relationship (SAR) and mechanism of paclitaxel and its analogues in recent years are discussed in the following areas: SAR of paclitaxel analogues toward "normal" and multi-drug resistance tumors; paclitaxel prodrugs with improved water solubitily and specificity; mechanism of paclitaxel related to tubulin binding and quest for its pharmacophore.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Paclitaxel/análogos & derivados , Paclitaxel/farmacologia , Animais , Antineoplásicos Fitogênicos/química , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Humanos , Paclitaxel/química , Relação Estrutura-Atividade , Tubulina (Proteína)/metabolismo
4.
Phytochemistry ; 38(3): 695-8, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7766164

RESUMO

Three new triterpenoid saponins were isolated from the alcoholic extract of the bark of Nothopanax davidii. Their structures have been determined on the basis of spectral and chemical data as 3-O-alpha-(4'-O-acetyl)-L-arabinopyranosyl-3 beta-hydroxyolean-12-ene- 28,29-dioic acid-28-O-[alpha-L-rhamnopyranosyl(1-->4)-beta-D-glucopyranosyl (1-->6)-beta-D-glucopyranosyl]ester, named yiyeliangwanoside IX; 3-O-alpha-(2'-O-acetyl)-L-arabinopyranosyl-3 beta-hydroxyolean-12-ene-28,29- dioic acid-28-O-[alpha-L-rhamnopyranosyl(1-->4)-beta-D-glucopyranosyl(1-->6)- beta-D-glucopyranosyl] ester, named yiyeliangwanoside X; and 3-O-beta-d-xylopyranosyl-3 beta-hydroxyolean-12-ene-28,29-dioic acid-28-O-[alpha-L-rhamnopyranosyl(1-->4)-beta-D-glucopyranosyl(1-->6)-b eta-D - glucopyranosyl] ester, named yiyeliangwanoside XI.


Assuntos
Plantas Medicinais , Saponinas/química , Triterpenos/química , Configuração de Carboidratos , Sequência de Carboidratos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Medicina Tradicional Chinesa , Dados de Sequência Molecular , Oligossacarídeos/química , Oligossacarídeos/isolamento & purificação , Rotação Ocular , Saponinas/isolamento & purificação , Espectrofotometria Infravermelho , Árvores , Triterpenos/isolamento & purificação
5.
Steroids ; 57(2): 67-71, 1992 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1621258

RESUMO

13,17-Secodiacholestanes (6) were synthesized from cholesterol (1) in six steps. The key intermediates, (20R)- and (20S)-diacholest-13(17)-enes (3a and 3b), underwent ozonization and reduction to provide (20R)- and (20S)-13,17-secodiacholesta-13,17-dione (5a and 5b), respectively. On Clemmensen reduction, the diones (5a and 5b) yielded the target molecule 6. The structure of an unknown biomarker was shown to be different from the proposed 6 by gas chromatographic/mass spectrometric comparison.


Assuntos
Colestanos/síntese química , Colesterol/química , Secoesteroides/síntese química , Colestanos/química , Cromatografia Gasosa-Espectrometria de Massas , Estrutura Molecular , Secoesteroides/química , Esteróis/química
6.
Steroids ; 55(6): 263-5, 1990 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2385850

RESUMO

5 alpha-(17R,20R)-14,15-Secocholestane (12) was synthesized from cholesterol (1) in 12 steps. The key intermediate, 5 alpha-cholest-14-en-3 beta-yl acetate (4), underwent ozonization, reduction, hydrolysis, and oxidation to provide 5 alpha-14,15-secocholesta-3,14,15-trione (8). One of the Clemmensen reduction products of 8 is 5 alpha(17R,20R)-14,15-secocholest-15-ol (11); treatment of the alcohol (11) with tosyl chloride and subsequent reduction with lithium aluminum hydride yielded the target molecule (12).


Assuntos
Compostos de Alumínio , Colestanos/síntese química , Compostos de Lítio , Secoesteroides/síntese química , Alumínio , Fenômenos Químicos , Química , Colesterol , Hidrólise , Lítio , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Oxirredução , Ozônio , Compostos de Tosil
7.
Yao Xue Xue Bao ; 28(6): 428-31, 1993.
Artigo em Zh | MEDLINE | ID: mdl-8249600

RESUMO

A new natural compound squamosamide isolated from Annona squamosa, was synthesized. This compound was characterized by 1H, 13CNMR and MS.


Assuntos
Anti-Infecciosos/síntese química , Antineoplásicos Fitogênicos/síntese química , Benzenoacetamidas , Fenóis/síntese química , Medicamentos de Ervas Chinesas/química , Estrutura Molecular , Fenóis/isolamento & purificação
8.
Yao Xue Xue Bao ; 27(5): 349-52, 1992.
Artigo em Zh | MEDLINE | ID: mdl-1442055

RESUMO

Securinine, an alkaloid having strychnine-like action was synthesized using 1,4-cyclohexanedione as the starting material through the following sequence of reactions: condensation with piperidine, reduction, cyclization catalyzed by mercuric acetate and intramolecular condensation, totally in eleven steps. The IR, 1HNMR and melting point of the synthetic product is identical with those of natural securinine.


Assuntos
Alcaloides/síntese química , Azepinas , Lactonas , Piperidinas , Alcaloides/química , Compostos Heterocíclicos de 4 ou mais Anéis , Compostos Heterocíclicos de Anel em Ponte
9.
Yao Xue Xue Bao ; 32(7): 515-23, 1997 Jul.
Artigo em Zh | MEDLINE | ID: mdl-11596277

RESUMO

Four classes of 25 tyrosine protein kinase (TPK) inhibitors were designed and synthesized. Compounds 1-10 were tested to inhibit TPK of HL-60 leukemia cell using 32P-ATP method, and some of them exhibit evident inhibitory activities. Their structure-activity relationship is similar to that of TPK inhibitors reported in literatures. Compounds 11-25 were tested to inhibit TPK of normal rat spleen cell using ELISA method and their SAR is different from that using 32P-ATP method.


Assuntos
Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/síntese química , Animais , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Células HL-60 , Humanos , Proteínas Tirosina Quinases/metabolismo , Ratos , Baço/citologia , Baço/metabolismo , Relação Estrutura-Atividade
10.
Yao Xue Xue Bao ; 27(11): 830-6, 1992.
Artigo em Zh | MEDLINE | ID: mdl-1300027

RESUMO

In this paper, the structure modification of triptolide was studied and nine triptolide derivatives were synthesized. A preliminary test for the immunosuppression activity in vitro showed that tripchlorolide (2) and tripbromolide (3) have strong activity similar to triptolide, while their toxicity are much lower. The activity of other compounds was decreased significantly. A simple method for the preparation of tripchlorolide from triptolide in 92% yield was found by reacting triptolide with HCl in acetone under mild condition.


Assuntos
Diterpenos/síntese química , Fenantrenos , Animais , Formação de Anticorpos/efeitos dos fármacos , Diterpenos/química , Diterpenos/farmacologia , Medicamentos de Ervas Chinesas/síntese química , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Ativação Linfocitária/efeitos dos fármacos , Camundongos , Relação Estrutura-Atividade
11.
Yao Xue Xue Bao ; 27(3): 191-6, 1992.
Artigo em Zh | MEDLINE | ID: mdl-1414384

RESUMO

Chrysanthemum indicum L. is a Chinese traditional drug used for antifebrile, detoxication and hypotensive purposes. In continuation of our efforts to search for the active principles of this species, a new sesquiterpene compound, named chrysanthetriol was isolated from the more polar fraction of the title plant. Chrysanthetriol is a colorless oil, [alpha]D20-31.8 degrees (c 0.3, MeOH). HRMS showed the molecular formula to be C15H26O3. The structure and stereochemistry of chrysanthtriol was elucidated as I by the use of 1H-1H COSY, 1H-13C COSY, 1H-13C COLOC 2D NMR spectroscopy.


Assuntos
Anti-Inflamatórios não Esteroides/química , Sesquiterpenos/química , Medicamentos de Ervas Chinesas/química , Espectroscopia de Ressonância Magnética/métodos , Conformação Molecular , Sesquiterpenos/isolamento & purificação
12.
Yao Xue Xue Bao ; 31(10): 764-9, 1996.
Artigo em Zh | MEDLINE | ID: mdl-9863245

RESUMO

Two new diterpenoids, named isodoternifolin A and B, together with seven known compounds were isolated from the ethanol extract of dried stems and leaves of Isodon ternifolius (D. Don) Kudo. Their structures were determined as 7 beta-hydroxy-6 beta, 11 alpha, 15 beta-triacetoxy-7 alpha, 20-epoxyentkaur-16-ene (1) and 6 beta, 7 beta, 15 beta-trihydroxy-11 alpha-acetoxy-7 alpha, 20-epoxy-entkaur-16-ene (2) by chemical and spectral evidence.


Assuntos
Diterpenos/isolamento & purificação , Lamiaceae/química , Plantas Medicinais/química , Diterpenos/química , Estrutura Molecular
13.
Yao Xue Xue Bao ; 24(6): 444-51, 1989.
Artigo em Zh | MEDLINE | ID: mdl-2609984

RESUMO

Two new nortriterpenoid saponins, named yemuoside YM10 (I) and YM12 (II), were isolated from Stauntonia chinensis Decne. A new prosaponin (VI) was isolated from the cleavage of ester-glycoside linkage. Their chemical structures were elucidated by means of chemical and spectrometric analysis. Yemuoside YM10 (I): C58H92O25, a white powder, mp 215-219 degrees C (dec), [alpha]D20-4.41 degrees (c 0.272, CH3OH). Its structure was found to be 28-O-alpha-L-rhamnopyranosyl- (1----4) -beta-D-glucopyranosyl- (1----6) -beta-D-glucopyranosyl ester of 3-O-alpha-L-rhamnopyranosyl-(1----2)-alpha-L-arabinopyranosyl-30-+ ++norolean-12, 20 (29) -dien-28-oic acid. Yemuoside YM12 (II): C52H82O21, a white powder, mp 200-204 degrees C (dec.), [alpha]D20 + 10.12 degrees (c 0.346, CH3OH). Its structure was found to be 28-O-beta-D-glucopyranosyl- (1----6) -beta-D-glucopyranosyl ester of 3-O-alpha-L-rhamnopyranosyl- (1----2) -alpha-L-arabinopyranosyl-30-norolean-12, 20 (29)-dien-28-oic acid. Prosaponin (VI): C40H62O11, a white powder, mp 243-246 degrees C (dec.), [alpha]D22 + 12.13 degrees (c 0.128, CH3OH). Its structure was found to be 3-O-alpha-L-rhamnopyranosyl- (1----2)-alpha-L-arabinopyranosyl-30-norolean-12, 20 (29)-dien-28-oic acid.


Assuntos
Medicamentos de Ervas Chinesas/análise , Saponinas/isolamento & purificação , Triterpenos , Fenômenos Químicos , Química
14.
Yao Xue Xue Bao ; 36(7): 502-6, 2001 Jul.
Artigo em Zh | MEDLINE | ID: mdl-12585080

RESUMO

AIM: To search for compounds having strong vasodilating effect. METHODS AND RESULTS: The mixed anhydride and alpha-phenylcinnamyl halide were used. Twenty-two alpha-phenylcinnamide derivatives were synthesized. The strutures were elucidated on the basis of MS and 1HNMR. Compounds 1-22 are new compounds. CONCLUSION: Vasodilative activity assays were conducted for the target compounds and the results indicated that several compounds (3, 9 and 11) demonstrated superior pharmacological profiles to the lead compound, among which compound 11 was further evaluated and found to be indicative of potential KCO activity. Preliminary SAR of alpha-phenylcinnamides was discussed herein.


Assuntos
Cinamatos/síntese química , Canais de Potássio de Abertura Dependente da Tensão da Membrana , Vasoconstrição/efeitos dos fármacos , Vasodilatadores/síntese química , Animais , Cinamatos/química , Cinamatos/farmacologia , Canais de Potássio de Retificação Tardia , Estrutura Molecular , Canais de Potássio/metabolismo , Ratos , Vasodilatadores/química , Vasodilatadores/farmacologia
15.
Yao Xue Xue Bao ; 32(12): 908-13, 1997 Dec.
Artigo em Zh | MEDLINE | ID: mdl-11596187

RESUMO

Many species of genus Hedyotis (Rubiaceae) were used as folk medicine for treatment of cold, inflammation, cancer and etc. in China. The alcoholic extract of the whole plant of H. chrysotricha showed good hepatoprotective effects. From the alcoholic extract ten iridoids were isolated and their structures were elucidated as: asperuloside (1), scandoside methyl ester (2), asperulosidic acid (3), deacetyl asperulosidic acid (4), loganin (5), deacetyl asperuloside (6), acetyl scandoside methyl ester (7), 6 beta-hydroxy-genipin (8) and two new compounds named hedyoside (9) and 6'-acetylasperuloside (10), by means of chemical and spectral methods.


Assuntos
Medicamentos de Ervas Chinesas/química , Glucosídeos/isolamento & purificação , Plantas Medicinais/química , Piranos/isolamento & purificação , Rubiaceae/química , Glucosídeos/química , Estrutura Molecular , Piranos/química
16.
Yao Xue Xue Bao ; 26(2): 117-22, 1991.
Artigo em Zh | MEDLINE | ID: mdl-1950566

RESUMO

Eight compounds were isolated from the acetone extract of artificially cultured mycelium of Armillaria mellea (Vahl. ex Fr.)Quel.(Tricholomataceae). Three of them are protoilludane sesquiterpenoid aromatic esters. Their structures were elucidated by spectral data analysis as the known 4'-methylmelledonal (I)and two new compounds named armillaritin (II) and armillarivin (III). In addition, five known compounds were identified as D-erythritol, D-mannitol, azelaic acid, orsellinic acid and glycerin-alpha-monooleate.


Assuntos
Agaricales , Medicamentos de Ervas Chinesas/química , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/química
17.
Yao Xue Xue Bao ; 25(1): 24-8, 1990.
Artigo em Zh | MEDLINE | ID: mdl-2363353

RESUMO

Two new protoilludane sesquiterpenoid aromatic esters, armillarilin C24H30O7, mp 179-180 degrees C, [alpha]D14 + 162 (c 0.97 CHC1(3] and armillarinin C24H29O7 C1, mp 152-155 degrees C, [alpha]D17 + 153.6, (c 0.09, CHC1(3], have been isolated from the artifically cultured mycelium of Armillaria mellea (Vahl. ex Fr.) Quel (Tricholometaceae). On the basis of spectral (UV, IR, 1HNMR, 13CNMR and MS) analysis their structures were identified as I and II, respectively.


Assuntos
Agaricales/análise , Sesquiterpenos/isolamento & purificação , Fenômenos Químicos , Química
18.
Yao Xue Xue Bao ; 32(11): 879-80, 1997 Nov.
Artigo em Zh | MEDLINE | ID: mdl-11596210

RESUMO

The crystal structure of villosolside was determined by X-ray diffraction, which led to some stereochemical amendment of the structure proposed in the article by Xu CJ et al. in Acta Pharm Sin 1985, 20:652.


Assuntos
Medicamentos de Ervas Chinesas/química , Lactonas/química , Plantas Medicinais/química , Cristalografia por Raios X , Lactonas/isolamento & purificação , Magnoliopsida/química , Conformação Molecular
19.
Yao Xue Xue Bao ; 36(3): 179-84, 2001 Mar.
Artigo em Zh | MEDLINE | ID: mdl-12580083

RESUMO

AIM: In order to improve the biological activity and reduce the side effects and toxicity, a series of novel estrogen receptor antagonists were designed. METHODS: The key triphenylethylene intermediates were obtained by the McMurry reaction. The target compounds were prepared by etherification. The binding affinities of the target compounds for the estrogen receptor in rat uterine cytosol were measured by a competitive binding assay and their estrogen agonistic/antagonistic properties were investigated in the 3-day uterine weight assay in the immature rats. RESULTS: Thirty-five new compounds have been synthesized and their geometric configuration were determined by X-ray crystallography and 1HNMR spectral data. CONCLUSION: All of the test compounds showed affinity for the estrogen receptor (IC50 < 10(-6) mol.L-1), especially compound 35 with IC50 1.07 x 10(-8) mol.L-1. Some compounds are antagonists, inhibiting uterus growth; others are agonists, promoting uterus growth. Compounds 14 and 27 are superior antagonists to tamoxifen.


Assuntos
Receptores de Estrogênio/antagonistas & inibidores , Estilbenos/síntese química , Útero/efeitos dos fármacos , Animais , Cristalografia , Feminino , Camundongos , Conformação Molecular , Estrutura Molecular , Tamanho do Órgão/efeitos dos fármacos , Estilbenos/química , Estilbenos/farmacologia , Útero/anatomia & histologia
20.
Yao Xue Xue Bao ; 25(5): 353-6, 1990.
Artigo em Zh | MEDLINE | ID: mdl-2284955

RESUMO

A new protoilludane sesquiterpenoid aromatic ester, named armillaripin, C24H30O6, mp 202-204 degrees C, [alpha]D15 + 130 degrees (c 0.055, CHCl3), was isolated from the petroleum ether extract of the artificially cultured mycelium of Armillaria mellea (Vahl. ex Fr.) Quel. (Tricolometaceae) by silica gel chromatography. On the basis of spectral (UV, IR, 1HNMR 13CNMR and MS) analysis its structure was deduced as I and confirmed by single-crystal X-ray analysis.


Assuntos
Agaricales/análise , Sesquiterpenos/isolamento & purificação , Fenômenos Químicos , Química , Conformação Molecular , Sesquiterpenos/química
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