bluuebunny/crossref_metadata_2025_split huggingface dataset:
The hand as a concept: Digital differences and their importance
Authors: Ranney Don 
Published: February 2005

AbstractDigits of the hand vary from each other with respect to bone and joint architecture, muscles, tendons, and degree of functional independence. The hand may be conceived as having a central rigid framework moved at the wrist by flexors, extensors, abductors, and adductors. But on each side of this central structure lies a mobile (hinged) segment necessary for pinch and to increase the strength of grasp. At the distal end of this triplex framework lie multijointed appendages essential for any type of pinch or grasp more sophisticated than that of a lobster claw. The thumb has a highly mobile carpometacarpal joint but lacks a middle phalanx. Therefore, it has no proximal interphalangeal (PIP) joint and consequently no mechanical need for a lumbrical. Since the thumb has excellent coordination without a lumbrical, the lumbrical's function as a sense organ cannot be simply to coordinate finger movement. Mechanically the lumbrical is a deflexor of the PIP joint. Because lumbricals are richly endowed with muscle spindles, their passive stretch by contraction of the flexor digitorum profundus might both inhibit finger extensors and facilitate wrist extensors. Since each digit is unique, accurate mathematical and computer modelling of the hand must take into consideration this uniqueness. © 1995 WiIey‐Liss, Inc.
A quantitative ultrastructural study of collagen fibrils in human skin normal scars, and hypertrophic scars
Authors: Stewart K. J. 
Published: February 2005

AbstractThe diameter‐distribution of collagen fibrils in the dermis of human skin and scar tissue has been investigated. In samples of normal skin, normal scar, and hypertrophic scar, prepared for transmission electron microscopy, collagen fibrils were systematically random‐sampled and their diameters measured. There was a statistically significant difference between the diameter‐distribution of fibrils in the papillary and reticular layers of dermis in normal skin. A similar pattern was found in normal scar, but not in hypertrophic scar. © 1995 WiIey‐Liss, Inc.
Variations in the lumbosacral ligament and associated changes in the lumbosacral region resulting in compression of the fifth dorsal root ganglion and spinal nerve
Authors: Briggs Christopher A. , Chandraraj Seba 
Published: February 2005

AbstractSixty‐five lumbosacral regions from adult cadavers were dissected and the position and relations of the lumbosacral ligament noted. The lumbosacral ligament was present in all specimens; in 22 (34%) it extended medially across the ventral ramus of the fifth lumbar nerve, and in six (9%) of these the underlying nerve was compressed and visibly flattened. On two of these specimens the nerve, together with its dorsal root ganglion, was removed, processed, and stained with Masson's trichrome. The compressed nerve showed increased thickness of endoneurial and perineurial connective tissue, and the cells of the dorsal root ganglion were smaller and surrounded by increased connective tissue, particularly at the periphery of the ganglion. Observation of the lumbosacral ligament and surrounding anatomical structures suggests that anatomical variation in this region may be attributed to the health of the lumbosacral articular elements. In those specimens showing compression of the fifth lumbar spinal nerve there was also narrowing of the lumbosacral interspace. In these the disc itself was compressed and showed degenerative changes. The articular processes at the lumbosacral joint were irregular, with thinning and fissuring of the articular cartilage. It is suggested that the processes which lead to the further development of the ligament, by the formation of additional fibrous bands, are mechanical in nature and result from instability at the lumbosacral region itself. Instability subsequently leads to the initiation of a chain of degenerative changes, involving pathology at the lumbosacral disc and zygapophyseal joints. Compression of the dorsal root ganglion occurs either within a narrowed inter vertebral foramen, or in the case described here just external to the foramen, while compression of the nerve occurs in the accessory ligamentous bands formed to resist the instability. A mechanism by means of which compression of the ganglion may give rise to pain is suggested. © 1995 WiIey‐Liss, Inc.
Topography of the perforating veins on the medial side of the leg (cockett's veins)
Authors: Staubesand J. , Hacklünder A. 
Published: February 2005

AbstractA macroscopic anatomical investigation was carried out on 67 embalmed dissecting‐room legs in order to determine the position, course, and origin of so‐called Cockett's perforating veins. This information was considered to be of particular importance because of the frequency with which varicoses in this region are treated with sclerosing agents and the serious adverse effects that can follow a misplaced injection. In view of the almost universal credence given to the accuracy of Cockett's original description (Cockett FP, 1955, Br. J. Surg. 43:260‐278 ), and the general acceptance of the constancy of “Cockett's veins,” it was felt to be of importance to see to what extent we could confirm this description. It was found that the origins of these vessels and the places at which they penetrate the deep fascia are not constant, and that—in our series—only 7.3% of the veins belonging to these groups occupy the positions that are repeatedly cited in the literature as the most common. The clinical importance of any discrepancy between expectation and reality can hardly be exaggerated. © 1995 WiIey‐Liss, Inc. © 1995 WiIey‐Liss, Inc.
Rotation of dissecting groups among different cadavers provides students of anatomy with increased opportunity to observe human variations
Authors: Champney Thomas H. , McCord Gary C. , Wayne Sampson H. 
Published: February 2005

AbstractOne way to increase medical students' awareness of anatomical variability is the dissection of different cadavers throughout laboratory coursework. This report covers such a procedure successfully instituted in a human gross anatomy course. © 1995 WiIey‐Liss, Inc.
Allylic Stereocontrol of the Intramolecular Diels–Alder Reaction
Authors: Lilly Michael J. , Miller Natalie A. , Edwards Alison J. , Willis Anthony C. , Turner Peter , Paddon‐Row Michael N. , Sherburn Michael S. 
Published: February 2005

AbstractThe stereochemical outcome of the intramolecular Diels–Alder reaction of ester‐linked 1,3,8‐nonatrienes can be controlled by substituents about a stereogenic center attached to C1. The scope and limitations of this approach have been investigated, with variation in substrate structure about the allylic stereocenter and the dienophile. The stereochemical outcomes of these reactions are explained by reference to B3 LYP/6–31G(d) transition structures. New insights into the conformational preferences of allylic alcohol derivatives are reported, results which allow an explanation of the differing levels of π‐diastereofacial selectivity and cis/trans (i.e. endo/exo) selectivity from the reaction.
Generation of Quaternary Stereocenters by Asymmetric Michael Reactions: Enamine Regiochemistry as Configuration Switch
Authors: Kreidler Burkard , Baro Angelika , Frey Wolfgang , Christoffers Jens 
Published: February 2005

AbstractRegioselective enamine formation from cyclic β‐diketones 1 is obtained by the appropriate choice of activating agent: Brønsted acid catalyzed condensation gives endocyclic enamines 3 as the thermodynamically favored products. Activation with Lewis acid BF3⋅OEt2 affords betaines 8 as intermediate products, which can be reacted with L‐valine diethylamide (2) to preferentially furnish exocyclic enamines 4 as kinetic products. Derivatives with quaternary stereocenters were accessible from both isomeric enamines by using asymmetric, copper(II)‐catalyzed Michael reactions at ambient temperature. Both regioisomers afford the triketones 7 with the same constitution but bearing the opposite absolute configuration at the quaternary stereocenter. Thus, both enantiomers of the product are prepared by using the same chiral auxiliary derived from L‐valine.
High‐Efficiency and Minimum‐Waste Continuous Kinetic Resolution of Racemic Alcohols by Using Lipase in Supercritical Carbon Dioxide.
Authors: Matsuda Tomoko , Watanabe Kazunori , Harada Tadao , Nakamura Kaoru , Arita Yoshitaka , Misumi Yukihiro , Ichikawa Shinichiro , Ikariya Takao 
Published: February 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Carbon Dioxide‐Expanded Liquid Substrate Phase: An Effective Medium for Selective Hydrogenation of Cinnamaldehyde to Cinnamyl Alcohol.
Authors: Zhao Fengyu , Fujita Shin‐ichio , Sun Jianmin , Ikushima Yutaka , Arai Masahiko 
Published: February 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Palladium‐Catalyzed Reaction of Boronic Acids with Chiral and Racemic α‐Bromo Sulfoxides.
Authors: Rodriguez Nuria , Cuenca Ana , Ramirez de Arellano Carmen , Medio‐Simon Mercedes , Peine Denissa , Asensio Gregorio 
Published: February 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Aqueous‐Phase, Palladium‐Catalyzed Cross‐Coupling of Aryl Bromides under Mild Conditions, Using Water‐Soluble, Sterically Demanding Alkylphosphines.
Authors: DeVasher Rebecca B. , Moore Lucas R. , Shaughnessy Kevin H. 
Published: February 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Rh‐Catalyzed Addition of Boronic Acids to Alkynes for the Synthesis of Trisubstituted Alkenes in a Biphasic System — Mechanistic Study and Recycling of the Rh/m‐TPPTC Catalyst.
Authors: Genin Emilie , Michelet Veronique , Genet Jean‐Pierre 
Published: February 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Solvent‐Free Al(OTf)3‐Catalyzed Aminolysis of 1,2‐Epoxides by 2‐Picolylamine: A Key Step in the Synthesis of Ionic Liquids.
Authors: Fringuelli Francesco , Pizzo Ferdinando , Tortoioli Simone , Vaccaro Luigi 
Published: February 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Synthesis of Cytotoxic 4‐Sulfonyl‐, 4‐Sulfonylthio‐ and 4‐Sulfothioazetidinones‐2.
Authors: Veinberg G. , Vorona M. , Musel D. , Bokaldere R. , Shestakova I. , Kanepe I. , Lukevics E. 
Published: February 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
The Samarium(II)‐Mediated Intermolecular Couplings of Ketones and β‐Alkoxyacrylates: A Short Asymmetric Synthesis of an Antifungal γ‐Butyrolactone.
Authors: Kerrigan Nessan J. , Upadhyay Tejas , Procter David J. 
Published: February 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Synthesis of Functionalized Spiro[cycloalkanono‐2,3′‐thiophenes] via Tandem Conjugate Addition—Cyclization of 3‐Oxoacid Thioanilides to Nitroalkenes.
Authors: Bogdanowicz‐Szwed Krystyna , Gil Regina 
Published: February 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Synthesis of Some 3‐(Arylalkylthio)‐4‐alkyl/aryl‐5‐(4‐aminophenyl)‐4H‐1,2,4‐triazole Derivatives and Their Anticonvulsant Activity.
Authors: Kuecuekguezel Ilkay , Kuecuekguezel Gueniz S. , Rollas Sevim , Oetuek‐Sanis Guelten , Oezdemir Osman , Bayrak Ibrahim , Altug Tuncay , Stables James P. 
Published: February 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Efficient Intramolecular Diels—Alder Reactions of Ester‐Tethered 1,7,9‐Decatrienoates Catalyzed by Bis‐Aluminated Trifluoromethanesulfonamide.
Authors: Saito Akio , Yanai Hikaru , Taguchi Takeo 
Published: February 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
A New Organic Superconductor β‐(meso‐DMBEDT‐TTF)2PF6.
Authors: Kimura Shinya , Maejima Tomoko , Suzuki Hideaki , Chiba Ryoma , Mori Hatsumi , Kawamoto Tadashi , Mori Takehiko , Moriyama Hiroshi , Nishio Yutaka , Kajita Koji 
Published: February 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
An Efficient, High Yield Protocol for the One‐Pot Synthesis of Dihydropyrimidin‐2(1H)‐ones Catalyzed by Iodine.
Authors: Bhosale Rajesh S. , Bhosale Sidhanath V. , Bhosale Sheshanath V. , Wang Tianyu , Zubaidha P. K. 
Published: February 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Synthesis of Substituted 5,6‐Dihydro‐4H‐[1,2,4]triazolo[4,3‐a][1,5]benzodiazepines.
Authors: Kosychova L. , Stumbreviciute Z. , Pleckaitiene L. , Janciene R. , Puodziunaite B. D. 
Published: February 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Copper‐Catalyzed Dimerization of Chromium Fischer Carbene Complexes: Synthesis of Dialkoxytrienes and Their Nazarov‐Type Cyclization to 2‐Alkoxy‐2‐cyclopentenones.
Authors: Barluenga Jose , Barrio Pablo , Vicente Ruben , Lopez Luis A. , Tomas Miguel 
Published: February 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Addition of Secondary Phosphines to a Vinyl Ether of Diacetone‐D‐Glucose: A New Approach to Optically Active Phosphines and Their Derivatives.
Authors: Trofimov Boris A. , Sukhov Boris G. , Malysheva Svetlana F. , Belogorlova Natal'ya A. , Tantsirev Anatolii P. , Parshina Lidiya N. , Oparina Ludmila A. , Tunik Sergey P. , Gusarova Nina K. 
Published: February 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Synthesis of N9‐ and N7‐[2‐Hydroxy‐3‐(phosphonomethoxy)propyl] Derivatives of N6‐Substituted Adenines, 2,6‐Diaminopurines and Related Compounds.
Authors: Krecmerova Marcela , Masojidkova Milena , Holy Antonin 
Published: February 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Comparative Immunologic and Kinetic Evaluation of AMP‐Deaminase Isolated from Normal Human Liver and Hepatocellular Carcinoma (HCC)
Authors: Szydlowska M. , Sledzinski Z. , Krzyzanowski M. , Nagel‐Starczynowska G. , Kaletha K. 
Published: February 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Amidox, an Inhibitor of Ribonucleotide Reductase, Potentiates the Action of Ara‐C in HL‐60 Human Promyelocytic Leukemia Cells
Authors: Bauer W. , Horvath Z. , Hoechtl T. , Saiko P. , Karl D. , Fritzer‐Szekeres M. , Szekeres T. Szekeres T. 
Published: February 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Cyclic Guanosine Monophosphate Role in Human Carcinoma Pathogenesis
Authors: Di Nicola Maurizio , Santoleri Fiorenzo , Soscia Stefano , Fioroni Massimiliano , Rubini Corrado , Piattelli Adriano , Spoto Giuseppe 
Published: February 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Control by calcium of the contractility of Labyrinthula slimeways and of the translocation of Labyrinthula cells
Authors: Nakatsuji Norio , Bell Eugene 
Published: February 2005

AbstractColonies of Labyrinthula, a colonial marine protist, expand by protrusive movements of the specialized slimeways. The movements recorded in time‐lapse films are of two types – filopodial and lamellipodial – and occur at rates equivalent to those of cell translocation.Evidence is presented that Ca2+ regulates the contraction of the actomyosin system of filaments present in the slimeways of Labyrinthula. In glycerinated models or in colonies exposed to ionophore A23187 contraction is evidenced by the occurrence of periodic contractions of the slimeways, giving them the appearance of strings of beads. Glycerinated slimeways contract on the addition of Ca2+ and ATP while slimeways provided with ionophore A23187 contract on addition of Ca2+ alone. The concentration required is 1.1 × 10−7 M Ca2+ while concentrations of 6.2 × 10−8 or lower were ineffective. Rates of contraction were measured in time‐lapse films which provide evidence that contractions and beading occur everywhere in the slimeway system. When beading occurs, the 6‐nm filaments transform from an array of parallel single filaments into an interwoven meshwork.We have identified by pyroantimonate‐OsO4 fixation, as possible Ca2+ reservoirs, deposits of Ca2+ in bothrosomes – structures through which cell secretions pass into the slimeways. The electron‐dense deposits are located at the base of the bothrosome and disappear after incubation with EGTA. We propose that the translocation of cells as well as the movements of slimeways may be regulated by the cells through the local measured liberation of Ca2+ from the bothrosome where it is sequestered.
An analysis of spindle ultrastructure during anaphase of micronuclear division in Tetrahymena
Authors: Lafountain James R. , Davidson Lloyd A. 
Published: February 2005

AbstractMitotic micronuclei were isolated from Tetrahymena thermophila and data on spindle ultrastructure were obtained from serial, transverse sections. Comparison of data from nuclei at meta‐ and early anaphase with data from nuclei at late anaphase showed that during anaphase, sister kinetochores move from the equator to the spindle poles, but kinetochore translocation occurs without any apparent change in either the number or length of kinetochore microtubules. This unprecedented result is ascribed significance with regard to the mechanism of kinetochore transport since there are only a limited number of ways that result could be achieved. The organization of the peripheral sheath changes during anaphase as evidenced by gaps in the sheath at late anaphase. Numerous kinetochore and non‐kinetochore microtubules are located in polar regions of the spindle at late anaphase, whereas those regions contained only peripherally arranged microtubules at earlier stages. Tracking of individual kinetochore microtubules in late anaphase nuclei showed that some of them appeared to become incorporated into the peripheral sheath near the pole. At early and late anaphase, crossbridges connect adjacent microtubules throughout the spindle poleward to the kinetochores, as well as in the interzone.
Identification of genetic elements associated with muscle structure in the nematode caenorhabditis elegans
Authors: Zengel Janice M. , Epstein Henry F. 
Published: February 2005

AbstractA search for new mutants with altered body‐wall muscle cell structure has been undertaken in the nematode C elegans. One‐hundred seventeen mutants were isolated after mutagenesis with ethyl methanesulfonate or ultraviolet light, enrichment by a motility‐requiring test, and screening by polarized light microscopy; 102 of these mutants were in ten previously established genes, whereas 15 mutants permitted the identification of seven new complementation groups in C elegans. Two of the new genes map on linkage group I (unc‐94 and unc‐95) and four genes are sex linked (unc‐96, unc‐97, unc‐98, and unc‐99). One complementation group (unc‐100) could not be mapped because of the special characteristics of its cohort mutants. Representative mutants of the mapped genes were examined by polarized light and electron microscopy. All of the mutants exhibit disruptions of the normal A and I band organization of thick and thin filaments. Several of the mutants produce collections of thin filament‐like structures. In one of these cases, HE177 demonstrated collections of somewhat wider, intermediate‐sized filaments as well, and the HE195 mutant produces paracrystalline aggregates of thin filaments amidst looser arrangements of similar structures. The mutants in newly identified genes, as well as the new mutants in previously established genetic loci, have promise as tools in the study of myofibrillar assembly and function. Among the 22 complementation groups associated with body‐wall structure in C elegans, it is likely that some genes code for regulatory and morphogenetic functions in addition to the well‐studied structural, contractile, and calcium‐associated proteins in muscle.
The role of the extracellular matrix in cell motility in fibroblast aggregates
Authors: Armstrong Margaret T. , Armstrong Peter B. 
Published: February 2005

AbstractThe effect of specific components of the extracellular matrix on the motility of tissue cells was studied using organ‐cultured aggregates of embryonic fibroblasts. Spherical aggregates of chick embryo heart and skin fibroblasts were fused with [3H]‐thymidine‐labeled aggregates of the identical cell type. The movement of labeled cells into the unlabeled partner aggregate served as an estimate of cell motility in the cultured tissue‐like aggregates. Collagenase treatment decreased the collagen content of heart fibroblast aggregates and increased cell motility; ascorbic acid treatment increased the collagen content of skin fibroblast aggregates and decreased cell motility. Reduction of the glycosaminoglycan content with testicular hyaluronidase had no measurable effect on cell motility in heart fibroblast aggregates.
Ultrastructural studies of a polygonal myofilament network in cultured rat aortic smooth muscle cells
Authors: Toselli Paul , Oliver Pamela , Cox Molly , Faris Barbara , Franzblau Carl 
Published: February 2005

AbstractCultured rat aortic smooth muscle cells (SMC) were examined by electron microscopy and found to contain polygonal networks of 75 A° thin myofilament bundles. The cells also had large bundles of longitudinally aligned thin myofilaments with periodically spaced dense bodies. Abundant plasmalemmal vesicles were present at the cell periphery, and the cells were connected by desmosomes. Intercellular spaces contained sparse amounts of elastic fibers, a material generally present in SMC cultures. Analyses of amino acids by automated column‐chromatography showed that isodesmosine and desmosine, two amino acid residues unique for elastin, were present. Accordingly, it was concluded that polygonal networks, previously detected solely in cultured nonmuscle cells, were present in SMC.Other findings suggest (1) a change in myofilament arrangement takes place during cell migration, and (2) rat aortic SMC grown in tissue culture flasks is an important experimental tool in the study of cell motility since such myofilament rearrangements were observed to occur up to fourteen days in first passage.
Chemotaxis in Tetrahymena thermophila
Authors: Almagor M. , Ron A. , Bar‐Tana J. 
Published: February 2005

AbstractThe motility pattern of Tetrahymena thermophila in a homogeneous attractant field consists of successive “runs” and “turns.” The turning frequency decreases or increases upon an abrupt increase in attractant or repellent concentration, respectively. The dose‐response curve for leucine and methionine yields a saturation curve with half maximum modulation of the turning frequency at a concentration of 15 μM and 2 μM, respectively. The turning frequency is modulated at a threshold concentration of 0.02 μM and 0.50 μM for leucine and methionine, respectively. The decrease (increase) in turning frequency in the presence of an attractant (repellent) jump reverts to prestimulus frequency in a time proportional to the concentration jump. Hence, Tetrahymena seem to employ temporal‐gradient sensing for chemotaxis. Spatial‐gradient taxis is thus exerted by random walk, which is biased in the direction of the gradient.