bluuebunny/crossref_metadata_2025_split huggingface dataset:
Novel and Rapid Synthetic Routes to A3B‐ and AB3‐Type 21‐Thiaporphyrins and Their Use in the Construction of Unsymmetrical Covalent and Non‐Covalent Porphyrin Arrays
Authors: Gupta Iti , Agarwal Neeraj , Ravikanth Mangalampalli 
Published: March 2004

AbstractNovel and very simple methods were developed for the synthesis of 21‐thiaporphyrins having both one functional group (A3B) and three functional groups (AB3). These A3B‐ and AB3‐type 21‐thiaporphyrin building blocks were used to synthesize both covalently and non‐covalently linked unsymmetrical porphyrin arrays containing N3S and N4 porphyrin cores. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Molecular Library Obtained by Allene Insertion into the Pd−C Bond of Cyclopalladated Complexes: Biological and Pharmacological Evaluation
Authors: Sirlin Claude , Chengebroyen Jaganaiden , Konrath Renato , Ebeling Günther , Raad Imad , Dupont Jairton , Paschaki Marie , Kotzyba‐Hibert Florence , Harf‐Monteil Colette , Pfeffer Michel 
Published: March 2004

AbstractA minilibrary of cationic N‐heterocycles has been prepared and evaluated. The potential for the preparation was a result of the high versatility of palladium‐mediated chemistry. The synthesis of the novel molecules was based on intramolecular quaternization of tertiary amine attached allylpalladium complexes. The steric and electronic factors of the reaction are discussed. The structures of the synthesized molecules made them candidates for precise biological and pharmacological evaluations. Of the various N‐heterocyclic compounds, 2,2‐dimethyl‐3‐methylenenaphtho[def]quinolizinium showed antibacterial activity at micromolar concentrations. This compound also proved to be a nanomolar competitive antagonist for the channel site of the nicotinic acetylcholine receptor. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Cover Picture: Formal Desymmetrization of the Diastereotopic Chains in Gemini Calcitriol Derivatives with Two Different Side Chains at C‐20 (Eur. J. Org. Chem. 8/2004)
Authors: Maehr Hubert , Uskokovic Milan R. 
Published: March 2004

AbstractThe cover picture shows symbolizes light that sustains life and the continuous evolution intimately connected to the critical role of vitamin D and its biomolecular receptor. It demonstrates the ability of mankind to supplement this evolutionary process by their inventions that contribute to health and well‐being. Details are discussed in the article by H. Maehr and M. R. Uskokovic on p. 1703 ff.
Electrochemical Characterization of the Self‐assembled Monolayer of 6‐Thioguanine on the Mercury Electrode
Authors: Arias Zoraida González , Muñiz Álvarez Jesús Luis , López Fonseca Juan Miguel 
Published: March 2004

AbstractA self‐assembled monolayer (SAM) of 6‐thioguanine (6TG) was formed on the hanging mercury drop electrode, under open circuit potential, from 6TG solutions. The SAM has been characterized by cyclic voltammetry under both in situ and ex situ conditions and the experimental data reveal that the film is a densely packed structure of chemisorbed (mercury‐thiol) molecules. The presence of this SAM has no influence on the rate of outer‐sphere electrode reactions but strongly inhibits inner‐sphere processes. The electrode reaction involving the Fe(CN)$\rm{ {_{6}^{3-/4-}}}$ couple appears reversible in a hanging mercury drop electrode coated by the 6TG‐SAM.
Amperometric Study of Au‐Colloid Function on Xanthine Biosensor Based on Xanthine Oxidase Immobilized in Polypyrrole Layer
Authors: Liu Yingju , Nie Lihua , Tao Wenyan , Yao Shouzhuo 
Published: March 2004

AbstractFour kinds of xanthine oxidase (XOD) based amperometric biosensors were fabricated and their analytical performances were compared. Polypyrrole (PPY)/XOD biosensor was constructed by electrochemical oxidation of pyrrole in the solution containing xanthine oxidase and pyrrole in this paper. Colloidal Au was then immobilized on the biosensor. On the other hand, electron mediator, Prussian Blue (PB), was deposited on the electrode before the immobilization of PPY/XOD to enhance electron‐transfer rate and current response. The results showed that PPY/XOD, PPY/XOD/Au‐colloid, PB/PPY/XOD and PB/PPY/XOD/Au‐colloid biosensors exhibit good response to xanthine in 1×10−6 M and 2×10−5 M and Michaelis‐Menten constants (Km) of these biosensors were 242.2, 113.4, 144.5, 43.2 μmol⋅L−1, respectively. The dependence of current responses with applied voltages was discussed, and different mechanisms of these biosensors were discussed. It has been found that colloidal Au can enhance the current response at the same concentration of xanthine solution and decrease the energy‐barrier of electron‐transfer reaction on the electrode.
Study on Electrochemiluminesce of Ru(bpy3)2+ Immobilized in a Titania Sol‐Gel Membrane
Authors: Zhuang Yafeng , Ju Huangxian 
Published: March 2004

AbstractThe immobilization of tris(2,2′‐bipyridyl)ruthenium(II), Ru(bpy)32+, at a glassy carbon electrode was achieved by entrapping the Ru(bpy)32+ in a vapor deposited titania sol‐gel membrane. The electrogenerated chemiluminescence (ECL) of the immobilized Ru(bpy)32+ was studied. The Ru(bpy)32+ modified electrode showed a fast ECL response to both oxalate and proline. The ECL intensity was linearly related to concentrations of oxalate and proline over the ranges from 20 to 700 μmol L−1 and 20 to 600 μmol L−1, respectively. The detection limits for oxalate and proline at 3σ were 5.0 μmol L−1 and 4.0 μmol L−1, respectively. This electrode possessed good precision and stability for oxalate and proline determinations. The electrogenerated chemiluminescence mechanism of proline system was discussed. This work provided a new way for the immobilization of Ru(bpy)32+ and the application of titania sol‐gel membrane in electrogenerated chemiluminescence.
Predictive control of seismic structures with semi‐active friction dampers
Authors: Lu Lyan‐Ywan 
Published: March 2004

AbstractIn this paper a predictive control method especially suitable for the control of semi‐active friction dampers is proposed. By keeping the adjustable slip force of a semi‐active friction damper slightly lower than the critical friction force, the method allows the damper to remain in its slip state throughout an earthquake of arbitrary intensity, so the energy dissipation capacity of the damper can be improved. The proposed method is formulated in a discrete‐time domain and cast in the form of direct output feedback for easy control implementation. The control algorithm is able to produce a continuous and smooth slip force for a friction damper and thus avoid exerting the high‐frequency structural response that usually exists in structures with conventional friction dampers. Using a numerical study, the control performance of a multiple degrees of freedom (DOF) structural system equipped with passive friction dampers and semi‐active dampers controlled by the proposed method are compared. The numerical case shows that by merely using a single semi‐active friction damper and a few sensors, the proposed method is able to achieve better acceleration reduction than the case using multiple passive dampers. Copyright © 2004 John Wiley & Sons, Ltd.
Chemical constituents of the essential oil of Lippia adoensis Hochst. ex Walp.
Authors: Kasali Adeleke A. , Ekundayo Olusegun , Winterhalter Peter , Koenig Wilfried A. , Eshilokun Adeolu O. 
Published: March 2004

AbstractThe composition of the essential oil of the leaves of Lippia adoensis Hochst. ex Walp. growing in Nigeria was determined by the use of GC and GC–MS. The leaf essential oil of L. adoensis predominantly comprised monoterpenoids (83.5%), of which linalool (26.1%), geraniol (19.0%) and 1,8‐cineole (17.4%) were the major constituents, while germacrene D (4.6%) was the main sesquiterpene identiﬁed in the oil. Copyright © 2004 John Wiley & Sons, Ltd.
Extraction of volatile compounds from Juniperus communis L. leaves with supercritical ﬂuid carbon dioxide: comparison with hydrodistillation
Authors: Pourmortazavi Seied Mahdi , Baghaee Parvin , Mirhosseini Mohammad Ali 
Published: March 2004

AbstractSupercritical ﬂuid extraction (SFE) of volatile oil from Juniperus communis L. leaves using carbon dioxide was carried out under different conditions of pressure, temperature, modiﬁer content and dynamic extraction time. A total of 22 compounds have been determined in these extracts by GC–FID and identiﬁed by GC–MSD, while in the hydrodistilled oil only 11 components were identiﬁed and quantiﬁed. The proposed extraction method has been compared with the hydrodistillation method. SFE products were found to be markedly different from the corresponding hydrodistilled oil. A remarkable amount of β‐phellandrene was present in the hydrodistilled essential oil; also, the ratio of α‐pinene to 3‐carene in distilled oil was high in comparison with the supercritical carbon dioxide extracts. The results showed that under a pressure of 200 atm, a temperature of 45 °C and a dynamic extraction time of 30 min, supercritical ﬂuid extraction of limonene was more selective, and under a pressure of 350 atm, a temperature of 45 °C and a dynamic extraction time of 20 min, extraction was more selective for the α‐thoujone, which was not identiﬁed in the hydrodistilled oil. Better results have been obtained with the proposed method in terms of rapidity, cleanliness and the possibility of manipulating the composition of the extract. Copyright © 2004 John Wiley & Sons, Ltd.
Dividing Olig2‐expressing progenitor cells derived from ES cells
Authors: Xian Haiqing , Gottlieb David I. 
Published: March 2004

AbstractG‐Olig2 is a knock‐in ES cell line with GFP inserted into the Olig2 gene so that ES cell‐derived neural cells that express Olig2 also express GFP. This tool allows visualization of the subset of cells that differentiate along the Olig2‐expressing pathway. By manipulating culture conditions, it is possible to induce Olig2 expression in rapidly dividing cells. These cells have many of the features of glial progenitor cells but, unlike other glial progenitors, are able to divide rapidly for at least 1 month while still expressing Olig2. Even after 1‐month expansion, the cells differentiate readily into astrocyte‐like and oligodendrocyte‐like cells when switched to serum‐containing medium. Cellular memory is the property whereby cells remain specified to a particular lineage or pathway while undergoing division. ES cell‐derived neural cells show cellular memory for a glial progenitor phenotype and thus provide a new and tractable model for this basic feature of neural development. © 2004 Wiley‐Liss, Inc.
Postoperative endocrine function in patients with surgically treated thyrotoxicosis
Authors: Sivanandan Ranjiv , Ng Lay Guat , Khin Lay Wai , Lim Teck Hock Dennis , Soo Khee Chee 
Published: March 2004

AbstractBackground.Endocrine function after surgery for thyrotoxicosis is difficult to predict. The operative morbidity and long‐term thyroid function of patients surgically treated for thyrotoxicosis is presented, and factors postulated to affect long‐term function are correlated with outcome.Methods.The clinical records of 289 consecutive patients who underwent surgery for thyrotoxicosis were reviewed. Indications for surgery, intraoperative findings, postoperative complications, and endocrine status 1, 2, and 5 years after surgery were analyzed. Sex, age, duration of medical treatment, weight of thyroid removed and preserved, and antimicrosomal/antithyroglobulin antibody status were correlated with outcome 5 years after surgery.Results.The incidence of permanent recurrent laryngeal nerve injury and hypocalcemia were 0.7% and 1.7%. The cumulative hypothyroid and hyperthyroid rates for the first, second, and fifth postoperative years were 13.8% and 3.5%, 14.5% and 4.8%, and 15.6% and 8.0%. All the prognostic variables analyzed did not achieve a significant correlation with outcome at 5 years by univariate and multivariate age‐ and sex‐adjusted relative risk.Conclusions.Failure from hypothyroidism develops early; recurrent hyperthyroidism increases with the number of years of follow‐up. Patients undergoing subtotal thyroidectomy warrant long‐term follow‐up because of the inability to accurately predict postoperative function with consistently reliable prognostic factors. © 2004 Wiley Periodicals, Inc. Head Neck 26: 331–337, 2004
Routine inclusion of level IV in neck dissection for squamous cell carcinoma of the larynx: Is it justified?
Authors: Khafif Avi , Fliss Dan M. , Gil Ziv , Medina Jesus E. 
Published: March 2004

AbstractBackground.Dissection of levels II–IV as part of an elective or therapeutic neck dissection is common practice during laryngectomy for laryngeal squamous cell carcinoma (SCC). The necessity of routine dissection at level IV has recently been questioned. The purpose of this study was to find the incidence of level IV metastases in patients with transglottic and supraglottic SCC who underwent neck dissections.Methods.The charts of 71 suitable patients were reviewed. Forty‐two had supraglottic primary cancers, and 29 had transglottic primary tumors. Levels II–IV had been removed in them all, and their neck specimens were marked according to the levels of the neck. The surgical specimens were pathologically diagnosed.Results.Of 43 patients who underwent elective lateral neck dissection, the only one (2.3%) with level IV metastases also showed metastases at level II. Nine (32%) of the other 28 patients with clinical adenopathy had level IV metastases.Conclusions.Dissection of level IV as part of a therapeutic neck dissection for supraglottic and transglottic SCC is recommended for patients with clinically enlarged lymph nodes, but its necessity in the absence of detectable adenopathy is challenged. © 2004 Wiley Periodicals, Inc. Head Neck 26: 309–312, 2004
Contingent labor as an enabler of entrepreneurial growth
Authors: Cardon Melissa S. 
Published: March 2004

AbstractWhile all firms can benefit from engaging contingent labor, due to the flexibility, real options, and new knowledge these workers may provide, these benefits are compounded in emerging organizations due to their lack of resources, legitimacy, and time to focus on HR issues. By carefully weighing the risks and benefits, and making purposeful and intentional decisions concerning when and what types of contingent labor to utilize, as well as how to manage and integrate them with traditional employees, emerging ventures may experience enhanced growth and productivity. This may be particularly true during their start‐up, expansion, and diversification stages of development.©2004 Wiley Periodicals, Inc.
Trust and its alternatives
Authors: Alvarez Sharon A. , Barney Jay B. , Bosse Douglas A. 
Published: March 2004

AbstractMost scholarly work on trust recognizes its importance as part of a nonmarket form of governance in exchanges
between firms. However, trust is only one such governance device that can be used; other devices such as
reputation, bargaining power, and contracts can also be used to govern exchanges. This article empirically
examines the relationships between trust, reputation, bargaining power, and contracts as governance devices in
agreements between smaller entrepreneurial firms and larger, more established firms. The findings suggest that
while the role of trust is an important one, it may be more effective when combined with other governance
devices. © 2004 Wiley Periodicals, Inc.
Microsatellite polymorphism of steroid hormone synthesis gene CYP11A1 is associated with advanced prostate cancer
Authors: Kumazawa Teruaki , Tsuchiya Norihiko , Wang Lizhong , Sato Kazunari , Kamoto Toshiyuki , Ogawa Osamu , Nakamura Akira , Kato Tetsuro , Habuchi Tomonori 
Published: March 2004

AbstractIt is widely recognized that androgen biosynthesis and metabolism are associated with the development and progression of prostate cancer. The human CYP11A1 gene (CYP11A1) encodes the P450scc enzyme, which mediates the first step in sex steroid hormone synthesis. The gene contains a (tttta)n‐5 bp tandem repeat microsatellite polymorphism located at 528 bp upstream of the translation initiation site and the CYP11A1 mRNA level may be modulated by the polymorphism. Recent studies suggested that the absence of the shortest (tttta)4 allele of the CYP11A1 polymorphism was associated with a risk of polycystic ovary syndrome and with a hyperandrogenic state in polycystic ovary syndrome patients. In our study which included 278 prostate cancer patients, 213 benign prostatic hyperplasia (BPH) patients and 299 male controls, we explored the association between the CYP11A1 polymorphism and prostate cancer on the hypothesis that the presence of the (tttta)4 allele may increase the risk of the development or progression of prostate cancer. In addition, we measured the serum levels of 6 steroid hormones or their metabolite (i.e., testosterone, free‐testosterone, estrone, estradiol, dehydroepiandrosterone and androstendione) in 156 control males subjects and compared those with and without the (tttta)4 allele. The polymorphism was evaluated by PCR amplification of a 145–170 bp fragment followed by polyacrylamid gel electrophoresis. The CYP11A1 allele consisted of 4, 6, 7, 8 and 9 (tttta)‐5 bp repeats. There was no significant difference in the genotype frequency as for the presence of the (tttta)4 allele between prostate cancer patients and male controls, and between prostate cancer patients and BPH patients. However, there was a significant difference in the genotype frequency in relation to the disease status. Prostate cancer patients without the (tttta)4 allele had an increased risk of metastatic disease (stage D) compared to those with the (tttta)4 allele [adjusted odds ratio (aOR)=1.76, 95% confidence interval (Cl)=1.07–2.90 and p =0.026]. Patients without the (tttta)4 allele had an increased risk of high grade prostate cancer (Gleason score 8 or more, or poorly differentiated cancer) compared to those with the (tttta)4 allele (aOR=1.79, 95% Cl=1.08–2.97 and p =0.025). No significant difference in the serum levels of 6 steroid hormones or their metabolites was found in the presence or absence of the (tttta)4 allele. Our results suggest that the CYP11A1 polymorphism may have a significant influence on the development of advanced and/or high grade prostate cancer and the absence of the CYP11A1 (tttta)4 allele, i.e., the homozygosity for the (tttta)6 or longer allele, could be a useful marker for the prediction of disease progression of prostate cancer. © 2004 Wiley‐Liss, Inc.
Digital photography: A primer for pathologists
Authors: Riley Roger S. , Ben‐Ezra Jonathan M. , Massey Davis , Slyter Rodney L. , Romagnoli Gina 
Published: March 2004

AbstractThe computer and the digital camera provide a unique means for improving hematology education, research, and patient service. High quality photographic images of gross specimens can be rapidly and conveniently acquired with a high‐resolution digital camera, and specialized digital cameras have been developed for photomicroscopy. Digital cameras utilize charge‐coupled devices (CCD) or Complementary Metal Oxide Semiconductor (CMOS) image sensors to measure light energy and additional circuitry to convert the measured information into a digital signal. Since digital cameras do not utilize photographic film, images are immediately available for incorporation into web sites or digital publications, printing, transfer to other individuals by email, or other applications. Several excellent digital still cameras are now available for less than $2,500 that capture high quality images comprised of more than 6 megapixels. These images are essentially indistinguishable from conventional film images when viewed on a quality color monitor or printed on a quality color or black and white printer at sizes up to 11×14 inches. Several recent dedicated digital photomicroscopy cameras provide an ultrahigh quality image output of more than 12 megapixels and have low noise circuit designs permitting the direct capture of darkfield and fluorescence images.There are many applications of digital images of pathologic specimens. Since pathology is a visual science, the inclusion of quality digital images into lectures, teaching handouts, and electronic documents is essential. A few institutions have gone beyond the basic application of digital images to developing large electronic hematology atlases, animated, audio‐enhanced learning experiences, multidisciplinary Internet conferences, and other innovative applications. Digital images of single microscopic fields (single frame images) are the most widely utilized in hematology education at this time, but single images of many adjacent microscopic fields can be stitched together to prepare “zoomable” panoramas that encompass a large part of a microscope slide and closely simulate observation through a real microscope. With further advances in computer speed and Internet streaming technology, the virtual microscope could easily replace the real microscope in pathology education. Later in this decade, interactive immersive computer experiences may completely revolutionize hematology education and make the conventional lecture and laboratory format obsolete. Patient care is enhanced by the transmission of digital images to other individuals for consultation and education, and by the inclusion of these images in patient care documents. In research laboratories, digital cameras are widely used to document experimental results and to obtain experimental data. J. Clin. Lab. Anal. 18:91–128, 2004. © 2004 Wiley‐Liss, Inc.
Evaluation of a novel kit (TF‐Test) for the diagnosis of intestinal parasitic infections
Authors: Gomes Jancarlo Ferreira , Hoshino‐Shimizu Sumie , S. Dias Luiz Cândido , Araujo Ana Júlia S.A. , Castilho Vera L.P. , Neves Fátima A.M.A. 
Published: March 2004

AbstractIntestinal parasitic infections are currently a source of concern for Public Health agencies in developing and developed countries. Since three ovum‐and‐parasite stool examinations have been demonstrated to provide sensitive results, we designed a practical and economical kit (TF‐Test) that is now commercially available (Immunoassay Com. Ind. Ltda., São Paulo, Brazil). This kit allows the separate collection of three fecal specimens into a preservative solution. The specimens are then pooled, double‐filtered, and concentrated by a single rapid centrifugation process. The TF‐Test was evaluated in four different laboratories in a study using 1,102 outpatients and individuals living in an endemic area for enteroparasitosis. The overall sensitivity found using the TF‐Test (86.2–97.8%) was significantly higher (P<0.01) than the sensitivity of conventional techniques such as the Coprotest (NL Comércio Exterior Ltda, São Paulo, Brazil) and the combination of Lutz/Hoffman, Faust, and Rugai techniques (De Carli, Diagnóstico Laboratorial das Parasitoses Humanas. Métodos e Técnicas, 1994), which ranged from 48.3% to 75.9%. When the above combined three specimen technique was repeated with three specimens collected on different days, its sensitivity became similar (P>0.01) to that of the TF‐Test. The kappa index values of agreement for the TF‐Test were consistent (P<0.01), being higher and ranking in a better position than conventional techniques. The high sensitivity, cost/benefit ratio, and practical aspects demonstrate that the TF‐Test is suitable for individual diagnosis, epidemiological inquiries, or evaluation of chemotherapy in treated communities. J. Clin. Lab. Anal. 18:132–138, 2004. © 2004 Wiley‐Liss, Inc.