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Centromeres remain the least characterized regions of human chromosomes because they have a very high content of repetitive DNA. Here, we describe a micro-dissection library from the centromeric region of human chromosome 7 and its use for generating sequence tagged sites (STSs). The library contains about 1500 clones with an average insert size of 150 bp and only about 15% of the clones harbour repetitive human DNA. Seven clones hybridizing to alphoid DNA were found to correspond to a fragment of the D7Z2 alphoid array on chromosome 7, thus confirming the origin of the library. A number of clones not containing known repetitive DNA were used to generate STSs that identified yeast artificial chromosomes (YACs) and in turn allowed the STSs to be placed on the physical map. One STS is located between the two Genethon genetic markers closest to the centromere on the q side. Another STS was located 3–4 cM away in 7q11.2, while a third identified YACs containing both low-copy and alphoid sequences that are not yet mapped but are clearly centromeric. The library therefore comprises a collection of sequences from the centromeric region of chromosome 7 that can be used to generate STSs and to map the entire centromeric region.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   
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Melanoma inhibitory activity (MIA) has been identified as a small protein secreted from malignant melanoma cells. Recent results revealed a direct interaction of MIA and epitopes within extracellular matrix proteins including fibronectin. The aim of this study was to analyze functional consequences mediated by this interaction. Here we show that MIA interferes specifically with attachment of melanoma cells to fibronectin, a phenomenon we refer to as active detachment. Antibodies inhibiting binding of alpha4beta1 and alpha5beta1 integrins to fibronectin cross-react specifically with MIA, suggesting that MIA shares significant structural homology with the binding pockets of these integrins and thereby masks the respective epitopes on extracellular matrix molecules. Several peptides derived from fibronectin and from a phage display screening were tested with respect to a potential MIA-inhibitory effect. In vitro tests identified two peptides affecting MIA function; both inhibited growth of melanoma metastases in vivo. In summary, we conclude that MIA may play a role in tumor progression and spread of malignant melanomas via mediating active detachment of cells from extracellular matrix molecules within their local milieu. Further, our results suggest that inhibiting MIA functions in vivo may provide a novel therapeutic strategy for metastatic melanoma disease.  相似文献   
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Fragestellung: Orbitotomien nehmen innerhalb der Ophthalmochirurgie auf Grund der involvierten anatomischen Strukturen und des daraus resultierenden Spektrums m?glicher perioperativer Probleme eine Sonderstellung ein. Um einen überblick über die Art und H?ufigkeit intra- und postoperativer Probleme bei Orbitotomien zu erhalten, führten wir eine retrospektive Auswertung an unserer Klinik durchgeführter Orbitotomien durch. Patienten und Methode: Es wurden 48 Orbitotomien bei 46 Patienten berücksichtigt, die zwischen 08/1995 und 02/1998 operiert wurden. Ergebnisse: Schwerwiegende intraoperative Komplikationen waren mit zwei transfusionspflichtigen Blutungen und einer Liquorfistel selten. Sie wurden interdisziplin?r behandelt. Postoperativ traten vorübergehende funktionelle St?rungen mit guter Rückbildungstendenz wie Visusminderungen (35 %), Motilit?tsst?rungen mit oder ohne Doppelbildwahrnehmung (20 %) und Lidfehlstellungen auf. Ihnen liegt v. a. die postoperative ?dem- und H?matombildung zugrunde. Persistierende Funktionseinschr?nkungen waren dagegen selten (10 %). Schlu?folgerung: Unsere Untersuchung zeigt, da? perioperativ bei Orbitotomien v. a. vorübergehende funktionelle Einschr?nkungen auftreten, die sich rasch zurückbilden. Schwere Komplikationen sind dagegen selten, treten v. a. intraoperativ auf und k?nnen eine interdisziplin?re Therapie erfordern.   相似文献   
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PURPOSE: The effect of whole body hyperthermia (WBH) at 41.8-42 degrees C on the cellular immune system is still poorly investigated. The aim of this study was to identify genes that become upregulated in peripheral blood lymphocytes (PBLs) of cancer patients during a combined treatment with WBH and chemotherapy by generating complex arrays of cDNA. METHODS: PBLs were obtained from four patients with different malignancies treated with WBH and varying cytostatic schedules before treatment and immediately thereafter. After constructing subtracted cDNA libraries, clones were screened for cDNA induction by dot-blot and semi-quantitative RT-PCR (sq-RT-PCR). RESULTS: Among 192 clones, 39 cDNAs were significantly upregulated. Sequencing revealed three groups of genes for which upregulation of mRNA was confirmed by sq-RT-PCR. The first group consisted of genes encoding for various heat shock proteins (HSP 60, 90a, 90b, 105). Further sq-RT-PCR demonstrated differential expression of HSP27 and HSP70 as well. The second group (calcyclin-binding-protein, haemoglobin-beta-chain) comprised genes without pre-specified association to hyperthermia. The cDNA encoding macrophage-inflammatory-protein-1-beta was also observed and may be associated with the pre-described activation of lymphocyte sub-populations during WBH. CONCLUSION: Treatment with WBH and chemotherapy elicits significant short-term effects on the expression of a variety of genes responsible for cellular integrity, stimulation and migration of immune effector cells. Further investigation is warranted to more clearly define the role of those genes for the clinical effect of WBH.  相似文献   
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Subtle subjective visual dysfunctions (VisDys) are reported by about 50% of patients with schizophrenia and are suggested to predict psychosis states. Deeper insight into VisDys, particularly in early psychosis states, could foster the understanding of basic disease mechanisms mediating susceptibility to psychosis, and thereby inform preventive interventions. We systematically investigated the relationship between VisDys and core clinical measures across three early phase psychiatric conditions. Second, we used a novel multivariate pattern analysis approach to predict VisDys by resting-state functional connectivity within relevant brain systems. VisDys assessed with the Schizophrenia Proneness Instrument (SPI-A), clinical measures, and resting-state fMRI data were examined in recent-onset psychosis (ROP, n = 147), clinical high-risk states of psychosis (CHR, n = 143), recent-onset depression (ROD, n = 151), and healthy controls (HC, n = 280). Our multivariate pattern analysis approach used pairwise functional connectivity within occipital (ON) and frontoparietal (FPN) networks implicated in visual information processing to predict VisDys. VisDys were reported more often in ROP (50.34%), and CHR (55.94%) than in ROD (16.56%), and HC (4.28%). Higher severity of VisDys was associated with less functional remission in both CHR and ROP, and, in CHR specifically, lower quality of life (Qol), higher depressiveness, and more severe impairment of visuospatial constructability. ON functional connectivity predicted presence of VisDys in ROP (balanced accuracy 60.17%, p = 0.0001) and CHR (67.38%, p = 0.029), while in the combined ROP + CHR sample VisDys were predicted by FPN (61.11%, p = 0.006). These large-sample study findings suggest that VisDys are clinically highly relevant not only in ROP but especially in CHR, being closely related to aspects of functional outcome, depressiveness, and Qol. Findings from multivariate pattern analysis support a model of functional integrity within ON and FPN driving the VisDys phenomenon and being implicated in core disease mechanisms of early psychosis states.Subject terms: Predictive markers, Psychosis  相似文献   
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Effectively managing and optimizing the value of the patent portfolio is a major challenge for many firms, especially those in knowledge intensive industries, such as the pharmaceutical, biotechnological and chemical industry. However, insights on effective patent portfolio strategies are rare. Therefore, in this article we investigate in detail how firms successfully manage and optimize their patent portfolios to increase their overall competitiveness. We discover that successful patent portfolio management is rooted in managing the patents along their life cycles. Based on the findings of ten case studies, we develop a holistic patent life cycle management model reflecting five distinctive phases of patent management: explore, generate, protect, optimize and decline. We conclude with how our findings can be used in practice.  相似文献   
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Angiogenesis, the process of development of a new microvasculature, is regulated by a balance of positive and negative factors. We show both in vivo and in vitro that the members of the human prolactin/growth hormone family, i.e., human prolactin, human growth hormone, human placental lactogen, and human growth hormone variant are angiogenic whereas their respective 16-kDa N-terminal fragments are antiangiogenic. The opposite actions are regulated in part via activation or inhibition of mitogen-activated protein kinase signaling pathway. In addition, the N-terminal fragments stimulate expression of type 1 plasminogen activator inhibitor whereas the intact molecules have no effect, an observation consistent with the fragments acting via separate receptors. The concept that a single molecule encodes both angiogenic and antiangiogenic peptides represents an efficient model for regulating the balance of positive and negative factors controlling angiogenesis. This hypothesis has potential physiological importance for the control of the vascular connection between the fetal and maternal circulations in the placenta, where human prolactin, human placental lactogen, and human growth hormone variant are expressed.  相似文献   
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IntroductionUncrossmatched ABO-compatible red blood cells (RBCs) are generally recommended in patients with life-threatening massive bleeding. There is little data regarding RBC transfusion when patients are transfused against clinically significant alloantibodies because compatible RBCs are not immediately available.Methods/PatientsAll patients reviewed in this study (n = 6,109) required emergency blood transfusion and were treated at the Charité − Universitätsmedizin Berlin between 2001 and 2015. Primary uncrossmatched O Rh(D)-positive or -negative RBC units were immediately transfused prior to complete regulatory serological testing including determination of ABO group, Rhesus antigens, antibody screening, and crossmatching.ResultsWithout any significant change in the protocol of emergency transfusion of RBCs, a total of 63,373 RBC units were transfused in 6,109 patients. Antibody screening was positive in 413 patients (6.8%), and 19 of these patients received RBC units against clinically significant alloantibodies. None of these patients appeared to have developed significant hemolysis, and only one patient with anti-D seems to have developed signs of insignificant hemolysis following the transfusion of three Rh(D)-positive units. One patient who had anti-Jka received unselected units and did not develop a hemolytic transfusion reaction.ConclusionTransfusion of uncrossmatched ABO-compatible RBCs against alloantibodies is highly safe in patients with life-threatening hemorrhage.  相似文献   
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