519 research outputs found
Clinical Study on Causative Factors and Recurrence of Choledocholithiasis
To identify factors involved in choledocholithiasis, clinical characteristics were studied
using univariate and multivariate analyses. Factors involved in recurrence were also
investigated. The subjects consisted of 51 patients with calcium bilirubinate stones (B group) and 52 patients with cholesterol stones (C group). All patients had choledocholithiasis
and underwent lithotripsy by endoscopic sphincterotomy (EST) during the
past 9 years. Twenty variables, including clinical symptoms and endoscopic retrograde
cholangiopancreatography (ERCP) findings, were analyzed using a Statistical Analysis
System (SAS) software package. Univariate analysis were done using Student's t-test and
the chi-square test. Multivariate analyses were done by stepwise logistic regression
analysis. In univariate analyses, there were significant differences between the B group
and C group in nine variables: age, common bile duct diameter, common hepatic duct
diameter, common bile duct stone diameter, cystic duct diameter, and the presence of
gallbladder stones, atypical arrangement of the hepatic duct, parapapillary diverticulum,
and large parapapillary diverticulum. In multivariate analysis, the four variables of
no gallbladder stone, large parapapillary diverticulum, cystic duct less than 8 mm, and
atypical arrangement of the hepatic duct were significant independent factors for the
development of stones in the B group, with relative risks of 37.75, 16.73, 5.56, and 5.49,
respectively. The results indicated that calcium bilirubinate stones were frequently associated
with parapapillary diverticulum and abnormal arrangement of the bile duct. The
formation of these stones was attributed to chronic biliary stasis caused by dysfunction
of the biliary tract, including the papilla. In contrast, most cholesterol stones found in the
common bile duct had apparently descended from the gallbladder. Common bile duct
stones recurred after EST in 9 patients, all of whom had calcium bilirubinate stones. On
ERCP, recurrence was found to be frequently associated with gallbladder stones, large
parapapillary diverticula, and atypical arrangement of the hepatic duct. Patients with
these characteristics on initial ERCP should therefore receive appropriate treatment
and undergo strict follow-up observations owing to the increased risk of recurrence
caused by dysfunction of the biliary tract
Whorl-Specific Expression of the SUPERMAN Gene of Arabidopsis Is Mediated by cis Elements in the Transcribed Region
The SUPERMAN (SUP) gene of Arabidopsis is involved in controlling cell proliferation in stamen and carpel primordia and in ovules during flower development. The SUP gene encodes a transcription factor with a C2H2-type zinc finger motif, a serine/proline-rich domain, a basic domain, and a leucine-zipper-like domain and is expressed in a very limited region in stamen primordia and in the developing ovary during flower development. The SUP gene is susceptible to methylation, resulting in epigenetic gene silencing. To understand how the SUP gene is expressed spatially and temporally in its restricted domain, and why methylation of the transcribed region affects early-stage SUP expression, we have identified the SUP cis regulatory elements by characterizing SUP gene fusions. These studies show that the SUP gene has discrete upstream promoter elements required for expression in stamen primordia in early stages and in the ovary in later stages. The promoter activity for stamen primordia is modulated by several positive and negative elements located in the transcribed and translated regions. Several regulatory elements in the transcribed region correlate with the areas of the gene that are heavily methylated in epigenetic alleles; these data provide a possible explanation of how methylation of the transcribed region represses transcription
SUPERMAN, a regulator of floral homeotic genes in Arabidopsis
We describe a locus, SUPERMAN, mutations in which result in extra stamens developing at the expense of the central carpels in the Arabidopsis thaliana flower. The development of superman flowers, from initial primordium to mature flower, is described by scanning electron microscopy. The development of doubly and triply mutant strains, constructed with superman alleles and previously identified homeotic mutations that cause alterations in floral organ identity, is also described. Essentially additive phenotypes are observed in superman agamous and superman apetala2 double mutants. The epistatic relationships observed between either apetala3 or pistillata and superman alleles suggest that the SUPERMAN gene product could be a regulator of these floral homeotic genes. To test this, the expression patterns of AGAMOUS and APETALA3 were examined in superman flowers. In wild-type flowers, APETALA3 expression is restricted to the second and third whorls where it is required for the specification of petals and stamens. In contrast, in superman flowers, APETALA3 expression expands to include most of the cells that would normally constitute the fourth whorl. This ectopic APETALA3 expression is proposed to be one of the causes of the development of the extra stamens in superman flowers. The spatial pattern of AGAMOUS expression remains unaltered in superman flowers as compared to wild-type flowers. Taken together these data indicate that one of the functions of the wild-type SUPERMAN gene product is to negatively regulate APETALA3 in the fourth whorl of the flower. In addition, superman mutants exhibit a loss of determinacy of the floral meristem, an effect that appears to be mediated by the APETALA3 and PISTILLATA gene products
Flume experiments in the development of crevasse-splay deposits: transition from asymmetric-to-symmetric geometry
Crevasse-splay deposits play an important role in the reconstruction of the magnitude of past flood events and in understanding the behavior of river systems. Despite the extensive studies conducted on the geometry and facies of crevasse-splay deposits, their spatiotemporal developmental processes have remained insufficiently understood. In this study, scaled flume experiments were conducted to study the relationship between the developmental processes of crevasse splays and their characteristics. An experimental flume was set up in a tank to simulate the 2019 Chikuma River flood, Central Japan event. To model the overbank flow, an opening was created on the side of the flume’s wall through which the flow flooded onto a horizontal acrylic plate. The sediment used in the experiments consisted of particles with grain sizes of approximately 0.3 and 0.1 mm, which were determined to be equivalent to bedload gravel and suspended sand in a real-scale river using dimensional analysis. The results of the experi ments revealed three important findings: (1) Crevasse-splay deposits initially developed an asymmetric shape extending downstream of the main river channel but gradually showed a symmetric geometry. The river mainstream initially influenced the direction of the inundation flow, but channel bifurcations after the deposition of the sediment piles later changed the geometry of splays into a more symmetric shape. (2) Crevasse-splay deposits developed in two distinct regions (proximal and distal splay), corresponding to sediment transport by bedload and suspended load, respectively. These two regions are commonly observed in the actual field scale. (3) The original overbank flow was a sheet flow without channels, which caused coarse-grained sediments to be spread over a wide area. Subsequently, the accumulation of coarse sands in the developed channel interiors resulted in the buildup of finer-grained sediments upstream of the proximal splay. Thus, the proximal splay deposits became slightly coarse downstream, whereas they rapidly became fine at the boundary with the distal splay. These findings indicate that the characteristics of crevasse-splay deposits vary with the landform’s development stage, thus providing a basis for interpreting their depositional facies
Functional analysis of block 5, one of the highly conserved amino acid sequences in the 130-kDa CryIVA protein produced by Bacillus thuringiensis subsp. israelensis
AbstractThere are five amino acid sequences highly conserved among Bacillus thuringiensis δ-endotoxins. We have changed the amino acid residues in block 5, one of the conserved sequences, of CryIVA. When the amino acid residues with charged side chains were replaced by others, the amount of production of the altered CryIVA protein was markedly decreased. It is suggested that the decrease is caused by the unstable conformation of the altered CryIVA protein molecule, as judged by digestion with trypsin and thermolysin. On the other hand, the substitution of amino acid residues in block 5 did not affect the insecticidal activity of CryIVA. These results strongly suggest that block 5 of CryIVA is one of the stability-determining elements of the protoxin molecule
The Practice of Basic Informatics 2020
Version 2020/04/02Kyoto University provides courses on 'The Practice of Basic Informatics' as part of its Liberal Arts and Sciences Program. The course is taught at many schools and departments, and course contents vary to meet the requirements of these schools and departments. This textbook is made open to the students of all schools that teach these courses. As stated in Chapter 1, this book is written with the aim of building ICT skills for study at university, that is, ICT skills for academic activities. Some topics may not be taught in class. However, the book is written for self-study by students. We include many exercises in this textbook so that instructors can select some of them for their classes, to accompany their teaching plans. The courses are given at the computer laboratories of the university, and the contents of this textbook assume that Windows 10 and Microsoft Office 2016 are available in these laboratories. In Chapter 13, we include an introduction to computer programming; we chose Python as the programming language because on the one hand it is easy for beginners to learn, and on the other, it is widely used in academic research. To check the progress of students' self-study, we have attached assessment criteria (a 'rubric') of this course as an Appendix. Current ICT is a product of the endeavors of many people. The "Great Idea" columns are included to show appreciation for such work. Dr. Yumi Kitamura and Dr. Hirohisa Hioki wrote Chapters 4 and 13, respectively. The remaining chapters were written by Dr. Hajime Kita. In revision for 2018 edition and after, Dr. Hiroyuki Sakai has participated in the author group, and Dr. Donghui Lin has also joined for English edition 2019. The authors hope that this textbook helps you to improve your academic ICT skill set. The content included in this book is selected based on the reference course plan discussed in the course development team for informatics at the Institute for Liberal Arts and Sciences. In writing this textbook, we obtained advice and suggestions from staffs of the Network Section, Information Infrastructure Division, Department of Planning and Information Management Department, Kyoto University on Chapters 2 and 3, from Mr. Sosuke Suzuki, NTT Communications Corporation also on Chapter 3, Rumi Haratake, Machiko Sakurai and Taku Sakamoto of the User Support Division, Kyoto University Library on Chapter 4. Dr. Masako Okamoto of Center for the Promotion of Excellence in Higher Education, Kyoto University helped us in revision of 2018 Japanese Edition. The authors would like to express their sincere gratitude to the people who supported them
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