bluuebunny/crossref_metadata_2025_split huggingface dataset:
Semiconducting polymers from triphenylamine derivatives‐benzaldehyde polymers by oxidization with 2,3‐dichloro‐5,6‐dicyano‐1,4‐benzoquinone (DDQ)
Authors: Wangwijit Tidarat , Sato Hisaya , Tantayanon Supawan 
Published: August 2002

Abstract4‐Tolyldiphenylamine (TDPA) and N,N′‐diphenyl‐N,N′‐bis(4‐methylphenyl)‐1,1′‐biphenyl‐4,4′‐diamine (TPD), were reacted with benzaldehyde (BA) using p‐toluenesulfonic acid as a catalyst to yield linear polymers. The polymers were reacted with 2,3‐dichloro‐5,6‐dicyano‐1,4‐benzoquinone (DDQ) in tetrahydrofuran (THF) at room temperature.
1H‐NMR showed that all the methine protons in the residue of BA were completely removed at the mole ratio of repeating unit : DDQ, 2 : 1. The resulting polymers showed good solubility in chloroform or THF. The reacted TDPA‐BA and TPD‐BA polymers gave new UV absorption peaks at 697.0 and 722.5 nm and showed reversible redox potentials about 0.994 and 1.021 V, respectively. Direct current (d.c.) conductivity of the reacted polymers was in the range of 10−11 S/cm, which is more than two orders higher than the unreacted polymers. The polymer showed pentad split electron spin resonance (ESR) signal, whose concentration was one in 670 or 230 repeating unit for TDPA‐BA and TPD‐BA polymers, respectively. Copyright © 2001 John Wiley & Sons, Ltd.
Amphiphilic copolymers with pendant ­carbazolylalkyl groups. ­Effect of polymer structure on ­retardation of self‐quenching
Authors: Itoh Yoshihiro , Shirai Hirofusa 
Published: August 2002

AbstractA series of amphiphilic polyanions containing (9‐carbazolyl)alkyl methacrylamide or acrylamide were prepared and their fluorescence properties were compared in organic and aqueous solution. In organic solution, all copolymers exhibited a monomer emission which decayed exponentially, indicating no self‐quenching. Decreasing the length of the methylene spacer in the side chain induced the spectral broadening and sharpening, depending on the carbazolyl content in the copolymer. This may be related to the interchromophore interactions and the mobility of chromophores. In H
2O, by contrast, quenched fluorescence was observed for the copolymers. It should be however noted that acrylamide‐type of amphiphilic copolymers, poly(9‐carbazolylmethyl‐acrylamide‐co‐sodium 2‐acrylamido‐2‐methylpropanesulfonate), are the least quenched polymers among those reported so far. Copyright © 2001 John Wiley & Sons, Ltd.
Anionic and ionic coordinative polymerization of ϵ‐caprolactone
Authors: Stere Cristina , Iovu Mihaela‐Corina , Iovu Horia , Boborodea Adrian , Vasilescu Dan Sorin , Read Simon James 
Published: August 2002

AbstractThe polymerization of ϵ‐caprolactone initiated by two catalyst systems was studied: (1) carbazole‐potassium in the presence of 18‐crown‐6 ether and (2) NdCl3/TBP/TIBA (neodymiumtrichloride/tri‐n‐butyl‐phosphate/triisobutylaluminium) at the molar ratio 1/3/1. For both initiator systems conversion/time plots were determined and the polymers were characterized by IR, GPC and by 1H‐ and 13C−NMR spectroscopy. Polyesters with the highest molecular weight (M
n≅44 000 g/mol) were obtained for the polymerizations initiated by the carbazole‐potassium/18‐crown‐6 ether system. The features of the polymerization initiated by the carbazole‐potassium/18‐crown‐6 ether system are discussed on the basis of a simple scheme. The nature of this polymerization is non‐living. Copyright © 2000 John Wiley & Sons, Ltd.
Symmetry C18 column: a better choice for the analysis of indole alkaloids of Catharanthus roseus†
Authors: Uniyal G. C. , Bala Shashi , Mathur A. K. , Kulkarni R. N. 
Published: August 2002

AbstractBy virtue of the different elution patterns of vindoline, catharanthine, vincristine and vinblastine present in the leaves of Catharanthus roseus plants, a Symmetry® C18 column provided a better resolution for all of these compounds as compared with other C18 columns. The binary gradient system with a linear gradient profile, employed in a method developed using a Symmetry C18 column, gave excellent peak symmetry, resolution and reproducibility. Detection was performed at 220 nm which presented better absorptivity for these indole alkaloids giving a minimum detection limit of 0.5 µg. Photodiode array detection was used to determine the homogeneity and purity of each compound. The described analysis is rapid and economical to perform as small amounts of solvent are consumed per analysis, and the method will find application where a large number of samples are to be analysed as, for example, in crop improvement studies where plants need to be selected regularly on the basis of alkaloid production. Copyright © 2001 John Wiley & Sons, Ltd.
Trisomy 10: ultrasound features and natural history after first trimester diagnosis
Authors: Brizot M. L. , Schultz R. , Patroni L. T. , Lopes L. M. , Armbruster‐Moraes E. , Zugaib M. 
Published: August 2002

AbstractWe report on the ultrasound features and natural history of trisomy 10. At 12 weeks' gestation in a routine scan examination, the fetus presented with increased nuchal translucency thickness, mild skin oedema, bilateral pleural effusion, marked micrognathia, cardiomegaly, unilateral talipes and reversed A‐wave in the ductus venosus blood flow. Karyotyping on chorionic villus sampling (CVS) led to the diagnosis of trisomy 10, which was confirmed by fetal blood sampling at 22 weeks' gestation. As the parents opted to continue with the pregnancy, the natural history and following ultrasound features are described. This is the third case of trisomy 10 in the literature reporting on the physical features. The most frequent ultrasound findings presented in trisomy 10 are increased nuchal translucency, micrognathia, renal agenesis, facial cleft, limbabnormalities, cardiac defects and early severe growth retardation. Copyright © 2001 John Wiley & Sons, Ltd.
Split notochord syndrome — prenatal ultrasonographic diagnosis
Authors: Almog B. , Leibovitch L. , Achiron R. 
Published: August 2002

AbstractSplit notochord syndrome is a rare condition that is characterized by a persistent connection of the gut and dorsal skin of the back, an enteric cyst and vertebral anomalies. We present two cases in which prenatal ultrasound showed polyhydramnios. In one case it was associated with vertebral abnormalities and a right‐sided mediastinal cyst found to be the stomach. Postnatal evaluation confirmed the diagnosis of split notochord syndrome. The association of sonographic findings of hydramnios, thoracic cysts and vertebral anomalies suggests prenatal diagnosis of split notochord syndrome. Copyright © 2001 John Wiley & Sons, Ltd.
The effect of a systemic arteriovenous fistula on the pulmonary arterial blood pressure in the fetal sheep
Authors: Jouannic J.‐M. , Martinovic J. , Roussin R. , Laborde F. , Dumez Y. , Dinh‐Xuan A. T. 
Published: August 2002

AbstractIn order to investigate whether systemic arteriovenous fistula occurring during the fetal period could induce pulmonary hypertension at birth, a fistula was surgically created between the carotid artery and jugular vein of fetal lambs at 120 days' gestation. Mean pressures in the left pulmonary artery, aorta, atrium and ventricles were measured at birth in seven experimental animals and in five control animals. Mean left pulmonary pressure was significantly higher in the lambs with fistula as compared with the control group, suggesting that prenatal occurrence of systemic arteriovenous fistula may induce fetal pulmonary hypertension. The present study provides a new animal model that could be relevant for the study of mechanisms regulating pulmonary vascular tone in the perinatal period. Copyright © 2002 John Wiley & Sons, Ltd.
Can we predict 22q11 status of fetuses with tetralogy of Fallot?
Authors: Boudjemline Younes , Fermont Laurent , Le Bidois Jérôme , Villain Elizabeth , Sidi Daniel , Bonnet Damien 
Published: August 2002

AbstractObjectiveTo determine if chromosome 22q11 deletion status can be predicted in fetuses with tetralogy of Fallot as regards additional phenotypic anomalies.MethodsOne hundred and fifty‐one consecutive fetuses with tetralogy of Fallot without or with pulmonary atresia were screened for 22q11 deletion. Additional echographic features [increased nuchal translucency (NT), intrauterine growth retardation (IUGR), polyhydramnios, extracardiac malformations, pulmonary arteries abnormalities] were noted.ResultsTwenty‐five fetuses had a 22q11 deletion (16.6%). Increased NT, polyhydramnios and IUGR were more frequent in fetuses with 22q11 deletion as well as pulmonary arterial abnormalities. When these different features were present in the same fetus with tetralogy of Fallot, 22q11 deletion can be predicted with a sensitivity of 88%.ConclusionSimple echographic features can help to predict 22q11 status in fetuses with tetralogy of Fallot. This may improve the efficiency of prenatal screening for this defect. Copyright © 2002 John Wiley & Sons, Ltd.
Prenatal diagnosis in two families with autosomal, p47phox‐deficient chronic granulomatous disease due to a novel point mutation in NCF1
Authors: de Boer Martin , Singh Vinita , Dekker Jan , Di Rocco Maja , Goldblatt David , Roos Dirk 
Published: August 2002

AbstractObjectivePrenatal diagnosis was required in two unrelated families with chronic granulomatous disease (CGD) patients who lacked expression of p47phox protein; thus a search for mutations in NCF1 was undertaken.MethodsGene scanning was applied to establish the relative number of coding and pseudo‐NCF1 genes. PCRs specific for coding NCF1 cDNA and coding NCF1 exon‐7 genomic DNA were devised.ResultsThe normal 1:2 ratio of coding and pseudo‐NCF1 genes was found in the patients. Sequencing of the RT‐PCR product specific for mRNA from the coding NCF1 genes revealed a novel homozygous G579A mutation in both patients, changing the TGG codon for Trp193 into the TAG stop codon. This mutation was confirmed in genomic DNA. The parents of both patients were found to be heterozygotes for this mutation. In the chorionic villus DNA of the first family a heterozygous G579A mutation was found. Postpartum, functional NADPH oxidase tests were normal. In the second family, this mutation was present in homozygous form in the chorionic villus DNA. Following termination of the pregnancy, the diagnosis of p47phox‐deficient CGD was confirmed on DNA extracted from fetal blood.ConclusionThis is the first report of prenatal diagnosis in p47phox‐deficient CGD. Copyright © 2002 John Wiley & Sons, Ltd.
Single umbilical artery stenosis associated with intrauterine fetal death post‐transfusion
Authors: Meir Karen , Yagel Simcha , Amsalem Hagai , Ariel Ilana 
Published: August 2002

AbstractSingle umbilical artery is among the most common funicular vascular anomalies. In contrast, umbilical artery stenosis is rare, and has only been reported in three‐vessel cords. We describe a case of single umbilical artery stenosis in a fetus with no associated malformations. Intrauterine fetal death occurred at 28weeks' gestation following cordocentesis and intravascular transfusion for Rhesus alloimmunization. Single umbilical artery stenosis may place the fetus at increased risk, particularly in cases requiring interventions involving cord manipulation. Copyright © 2002 John Wiley & Sons, Ltd.
Does a ‘notched’ nuchal translucency indicate Down syndrome fetuses or other adverse pregnancy outcome?
Authors: Maymon Ron , Dreazen Eli , Buckovsky Ian , Weinraub Zwi , Herman Arie 
Published: August 2002

AbstractThe aim of the present study was to assess the sonographic contour of the increased nuchal translucency (NT) and to correlate this with pregnancy outcome. Fifty sonographic images of fetuses with increased NT [>95th centile thickness of the normal range for crown–rump length (CRL) between 38 and 84 mm] were retrospectively assessed. In all the cases a complete pregnancy and even infancy follow‐up (<36 months) was available. The NT appearances were subdivided into two forms: a ‘notched’ or ‘uniform’ appearance. The images were correlated with karyotype results [trisomy 21 (DS) vs euploid cases] and pregnancy outcome. Complicated outcomes were classified as being either DS fetuses, miscarriage or termination of pregnancy because of structural anomaly. Thus 30/35 (86%) of the euploid fetuses had a ‘uniformly’ increased NT, whereas 8/13 DS cases (62%) had a ‘notched’ appearance (Fisher's exact test, p=0.004). Additionally, 27/29 fetuses (93%) which had an uneventful pregnancy outcome had a ‘uniform’ increased NT, whereas 12/26 (57%) of the fetuses which had adverse pregnancy outcome had a ‘notched’ appearance of their NT (Fisher's exact test, p<0.001). Although it was not possible to correlate the sonographic data with post‐evacuation microdissection findings, it is possible that a uniformly shaped, increased NT may be more representative of a developmental delay in a normal fetus. Conversely, a ‘notched’ nuchal surface may represent abnormal lymphatic or cardiovascular development more commonly seen in DS fetuses. Copyright © 2001 John Wiley & Sons, Ltd.
Minimized analysis of costs applied to antimicrobial consumption in a rural area
Authors: Sánchez Cristina Corres , Nájera Lorena Hermosilla , Inchaurregui Luis Carlos Abecia 
Published: August 2002

AbstractPurposeAntimicrobial agents constitute one of the most utilized groups of drugs in daily clinical practice and, therefore they involve a significant expense. The aim of this study was to evaluate the economic cost of the antimicrobials prescribed in a rural area as well as to search for some cheaper alternatives.MethodsRetrospective study. The economic cost of antimicrobial agents prescribed at a health centre over 18 months was studied. To do this, clinical histories of 800 people were reviewed. Afterwards, a minimized analysis of costs was carried out.ResultsThe total cost of antimicrobial consumption came to 2 080 752 pts. The average expenditure per patient came to 6433.85 ± 14 269.29 pts. Significant differences between the sexes were not found; however, the expenditure in patients of 65 years of age or over was significantly higher than the rest. After applying the ABC analysis it was noticed that macrolides, cephalosporins, antimicrobial combinations and quinolones were the most important groups from an economic point of view. The use of monodose containers would allow us to save up to 7.83% of the total expenditure. In addition, by prescribing the cheapest marketed pharmaceutical product we could save a further 6.54%, and, finally, by combining these two measures the total possible saving would reach 299 052 pts, a 14. 37% of the total expenditure.ConclusionWe consider important the elaboration of pharmacoeconomic guides as well as the introduction of monodose containers not only at hospitals but also at community pharmacists. Copyright © 2001 John Wiley & Sons, Ltd.
Advances in identifying women at risk of breast cancer and in treating the disease
Authors: Howell Anthony 
Published: August 2002

AbstractEpidemiological studies have identified risk factors for breast cancer. The majority of these are related to estrogen exposure, such as early menarche, late menopause, and use of oral contraceptives and hormone replacement therapy. More recently, part of the reason for familial breast cancer has been explained. In families with multiple breast and/or ovarian cancers there is likely to be mutations in the cell‐cycle control/DNA repair genes BRCA‐1, BRCA‐2 and p53. It is now routine in major centres to test for mutations. When found, preventive measures such as prophylactic mastectomy can be discussed with women. About 5–10% of breast cancer is caused by gene mutation. We do not know the initiating factors in the remainder but we know that a large proportion are related to estrogen, which increases proliferation of normal breast epithelial cells, thus increasing the chances of carcinogenesis, and also promotes proliferation of the altered cell afterwards.The importance of estrogen has been translated into therapy, first by ovarian ablation and in recent years by antiestrogens and, in post menopausal women, the aromatase inhibitors, which lower serum estrogen concentrations. Antiestrogens (e.g., tamoxifen) were shown to be effective for the treatment of advanced breast cancer over thirty years ago. This led to their use after surgery. When given for five years, deaths are reduced by 10–20%. Together with early diagnosis and mammographic screening it is likely that tamoxifen has contributed to the 30% reduction in breast cancer deaths in the UK. Now tamoxifen is used to prevent breast cancer in women at risk. An American study (NSABP P1) of 14 000 women showed that those randomized to tamoxifen had 50% fewer invasive and in‐situ cancers compared with controls given placebo. If this result is replicated in the UK trial (IBIS I), tamoxifen may be more widely used for women at risk. Similar reductions in breast cancer risk were seen in a study using the antiestrogen raloxifene, which has the advantage of not causing endometrial stimulation. Tumours which arise in women given preventative antiestrogens are mostly estrogen receptor negative. In the future we need to find how to prevent these and also to evaluate the preventative effects of lifestyle changes, such as weight loss and increased physical activity. Copyright © 2001 John Wiley & Sons, Ltd.
Drug use investigation (DUI) and prescription‐event monitoring in Japan (J‐PEM)
Authors: Tanaka Katsutoshi , Morita Yasuko , Kawabe Eri , Kubota Kiyoshi 
Published: August 2002

AbstractObjectiveTo present ethical issues and relevant problems in observational studies of drug safety in Japan.MethodsThe Pharmaceutical Affairs Law, associated ordinances, and notifications relevant to Drug Use Investigations (DUIs), and published documents for two pilot studies of prescription‐event monitoring in Japan (J‐PEM) were examined, particularly with regard to the protection of privacy. Information relevant to the proposed legislation intended to protect personal information and proposed guidelines on ethical issues in epidemiological studies were also collected.Results and ConclusionThe formal studies inaugurated as the ‘side‐effect investigations’ in the late 1960s and replaced by those of the DUI in 1980 have been conducted by drug manufacturers, in accordance with the Pharmaceutical Affairs Law. The first pilot study of J‐PEM was started in 1997 and the second one is currently operated under a Health Sciences Research grant, supported by the Ministry of Health and Welfare. Those observational studies have been conducted while maintaining the confidentiality of personal data, but without requiring either approval by institutional ethics boards or informed consent from patients. However, according to the Pharmaceutical Affairs Law, those involved in postmarketing surveillance studies must protect the privacy of study subjects and those who break this rule may be subject to penalties. Ethical issues associated with pharmacoepidemiological studies will be clearly determined in Japan before the end of 2001 when the law designed to protect personal information will be introduced and official guidelines on ethical issues in epidemiological studies will have come into effect. Copyright © 2001 John Wiley & Sons, Ltd.
Radical polymerization of styrene by a hexa‐substituted‐ethane type thermal iniferter
Authors: Qin Shu‐Hui , Qiu Kun‐Yuan , Swift Graham , Wu Shuguang , Westmoreland David G 
Published: August 2002

AbstractThe bulk polymerization of styrene (St) initiated with a hexa‐substituted‐ethane type initiator, diethyl 2,3‐dicyano‐2,3‐diphenylsuccinate (DCDPS), was investigated. It was found that DCDPS served as a thermal iniferter for polymerization of St and the polymerization had some characteristics in common with living radical polymerization, ie, both the yield and the molecular weight of the resulting polymers increased with increasing reaction time. The resultant polystyrene can act as a macroinitiator for chain‐extension polymerization of St or for radical polymerization of methyl methacrylate to give a block copolymer.© 2001 Society of Chemical Industry
Study of kinetics and mechanisms of dispersion polymerization of 2‐hydroxypropyl methacrylate
Authors: Wang Yan‐Jun , Liu Jin‐Mei , Yuan Cai‐Deng , Liu Jiang‐Feng , Tan Xin , Cao Tong‐Yu 
Published: August 2002

AbstractIn the present work, the dispersion polymerization of 2‐hydroxypropyl methacrylate (HPMA) was carried out in No. 120 gasoline/n‐pentanol medium using azobisisobutyronitrile as initiator and a comb‐structured amphipathic polymer as dispersant. The effects of many factors such as the type, structure and concentration of dispersants, and the reaction temperature, on the reaction and the morphology of the polymer microspheres obtained were investigated. It is proposed that the dispersion polymerization of HPMA has two nucleation mechanisms, homogeneous nucleation and inverse mini‐emulsion nucleation. Furthermore, the kinetic of HPMA dispersion polymerization was also studied.© 2001 Society of Chemical Industry
Synthesis and characterization of poly(urethane‐co‐imidine)s having pendent phenyl and benzylidene groups using bisphthalides, bislactones and blocked polyurethane prepolymers
Authors: Iyer N Padmanabha , Nasar A Sultan , Gnanarajan T Philip , Radhakrishnan Ganga 
Published: August 2002

AbstractPoly(urethane‐co‐imidine)s were prepared using amine blocked polyurethane (PU) prepolymer. The PU prepolymer was prepared by the reaction of poly(propylene glycol) (PPG2000) and 2,4‐tolylene diisocyanate (TDI) and end capped with N‐methyl aniline. The PU prepolymer was then reacted with bisphthalides and bislactones, until the evolution of carbon dioxide ceased. Polymerization reactions with bispthalides and bislactone took more time than with dianhydrides. Polymers were characterized by FTIR, GPC, TG and DSC analyses. Molecular weights of the poly(urethane‐co‐imidine)s were found to be lower than that of poly(urethane‐co‐imide)s. Compared to poly(urethane‐co‐imide)s all poly(urethane‐co‐imidine)s showed high glass transition temperature and crystallization peak in DSC. The thermal stability of the polyurethanes was found to increase with the introduction of imidine component.© 2001 Society of Chemical Industry
Synthesis and characterization of a random terpolymer of L‐lactide, ϵ‐caprolactone and glycolide
Authors: Srisa‐ard Mangkorn , Molloy Robert , Molloy Nipapan , Siripitayananon Jintana , Sriyai Montira 
Published: August 2002

AbstractA random terpolymer of L‐lactide (LL), ϵ‐caprolactone (CL) and glycolide (G) has been synthesized in bulk at 130 °C using stannous octoate as the coordination–insertion initiator. The terpolymer, poly(LL‐ran‐CL‐ran‐G), has been characterized by a combination of analytical techniques: GPC, 1H NMR, 13C NMR, DSC and TG. Molecular weight characterization by GPC shows a unimodal molecular weight distribution with values of
M
n = 1.01 × 105 g mol−1 and
M
w /
M
n = 2.17. Compositional and microstructural analysis by 1H NMR and 13C NMR, respectively, reveal a terpolymer composition of LL:CL:G = 74:15:11 (mol%) with a chain microstructure consistent with random monomer sequencing. This latter view is supported by the terpolymer temperature transitions (Tg and Tm) from DSC and the thermal decomposition profile from TG. The results and, in particular, the conclusion that it is a random rather than a statistical terpolymer are discussed in the light of current theories regarding the mechanism of this type of polymerization.© 2001 Society of Chemical Industry