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31.
Chronic pancreatitis is a persistent inflammatory disease of the pancreas, in which the digestive protease trypsin has a fundamental pathogenetic role. Here we have analyzed the gene encoding the trypsin-degrading enzyme chymotrypsin C (CTRC) in German subjects with idiopathic or hereditary chronic pancreatitis. Two alterations in this gene, p.R254W and p.K247_R254del, were significantly overrepresented in the pancreatitis group, being present in 30 of 901 (3.3%) affected individuals but only 21 of 2,804 (0.7%) controls (odds ratio (OR) = 4.6; confidence interval (CI) = 2.6-8.0; P = 1.3 x 10(-7)). A replication study identified these two variants in 10 of 348 (2.9%) individuals with alcoholic chronic pancreatitis but only 3 of 432 (0.7%) subjects with alcoholic liver disease (OR = 4.2; CI = 1.2-15.5; P = 0.02). CTRC variants were also found in 10 of 71 (14.1%) Indian subjects with tropical pancreatitis but only 1 of 84 (1.2%) healthy controls (OR = 13.6; CI = 1.7-109.2; P = 0.0028). Functional analysis of the CTRC variants showed impaired activity and/or reduced secretion. The results indicate that loss-of-function alterations in CTRC predispose to pancreatitis by diminishing its protective trypsin-degrading activity.  相似文献   
32.
The dystonias are a common clinically and genetically heterogeneous group of movement disorders. More than ten loci for inherited forms of dystonia have been mapped, but only three mutated genes have been identified so far. These are DYT1, encoding torsin A and mutant in the early-onset generalized form, GCH1 (formerly known as DYT5), encoding GTP-cyclohydrolase I and mutant in dominant dopa-responsive dystonia, and TH, encoding tyrosine hydroxylase and mutant in the recessive form of the disease. Myoclonus-dystonia syndrome (MDS; DYT11) is an autosomal dominant disorder characterized by bilateral, alcohol-sensitive myoclonic jerks involving mainly the arms and axial muscles. Dystonia, usually torticollis and/or writer's cramp, occurs in most but not all affected patients and may occasionally be the only symptom of the disease. In addition, patients often show prominent psychiatric abnormalities, including panic attacks and obsessive-compulsive behavior. In most MDS families, the disease is linked to a locus on chromosome 7q21 (refs. 11-13). Using a positional cloning approach, we have identified five different heterozygous loss-of-function mutations in the gene for epsilon-sarcoglycan (SGCE), which we mapped to a refined critical region of about 3.2 Mb. SGCE is expressed in all brain regions examined. Pedigree analysis shows a marked difference in penetrance depending on the parental origin of the disease allele. This is indicative of a maternal imprinting mechanism, which has been demonstrated in the mouse epsilon-sarcoglycan gene.  相似文献   
33.
  总被引:42,自引:0,他引:42  
H C Berg 《Nature》1974,249(452):77-79
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34.
L Soll  P Berg 《Nature》1969,223(5213):1340-1342
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35.
36.
  总被引:119,自引:0,他引:119  
H C Berg  D A Brown 《Nature》1972,239(5374):500-504
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37.
R C Mulligan  B H Howard  P Berg 《Nature》1979,277(5692):108-114
Rabbit beta-globin complementary DNA (cDNA) has been inserted into SV40 DNA in place of the gene coding for the virus' major capsid protein, VP1. The recombinant genome, SVGT5-RabetaG, multiplies efficiently in CV1 monkey kidney cell cultures and is transcribed to yield cytoplasmic, polyadenylated hybrid mRNAs containing the beta-globin coding sequence. Cells propagating SVGT5-RabetaG produce substantial quantities of rabbit beta-globin polypeptide.  相似文献   
38.
  总被引:2,自引:0,他引:2  
R J van den Berg  E Siebenga  G de Bruin 《Nature》1977,265(5590):177-179
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39.
    
I Heron  K Berg 《Nature》1978,274(5670):508-510
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40.
A visual language of pictures, such as the rich picture used in the Soft System Methodology, offers a way of global communication that far exceeds the limitations of text and speech. Simple graphics can be rapidly communicated, processed and transmitted within a large and culturally diverse constituency. This paper looks at the benefits and interpretative risks when using rich pictures for system understanding. The aim of this paper is twofold: firstly to report upon an observation of a large scale collaborative diagramming workshop and compare the resulting pictures with a previous workshop study. Secondly, to develop further ongoing research which suggests rich picture construction can be aided by providing an icon legend. This paper compares 2 rich picture workshops: the diagramming workshop at the Open University eSTEeM Diagramming Colloquium in March 2012 and a workshop held in Heriot Watt University in February 2012. The comparative results are set against the ongoing empirically grounded rich picture research within Heriot-Watt University in Scotland. Preliminary results suggest there are a set of distinguishable icons and shapes that are generic across all rich pictures regardless of domain. Further analysis of the early results suggests a natural intrinsic grammar is manifested within rich pictures in terms of relationships, icons, context and connectors.  相似文献   
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