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61.
Immunohistochemical detection of bcl-2 protein in normal and pathological human liver. 总被引:12,自引:4,他引:12
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F. Charlotte A. L'Hermin N. Martin Y. Geleyn M. Nollet P. Gaulard E. S. Zafrani 《The American journal of pathology》1994,144(3):460-465
The bcl-2 protein, which prolongs cell survival by blocking apoptosis, is expressed by progenitor cells in several self-renewing tissues and by tumoral cells in some extrahepatic neoplasms. Because the liver is a slow self-renewing tissue, an immunohistochemical study of the cellular distribution of the bcl-2 protein was performed in normal liver (12 cases), nontumoral hepatic lesions (33 cases), and benign or malignant liver tumors (46 cases). In normal liver, bcl-2 was expressed by bile ductules and small bile duct epithelium, but not by hepatocytes or large bile duct epithelium. In cirrhosis and focal nodular hyperplasia, epithelial cells of the ductular proliferation were bcl-2-positive. Eight of 11 cholangiocarcinomas stained positively for bcl-2, whereas all 15 hepatocellular carcinomas were bcl-2-negative. bcl-2 was also expressed in 6 of 14 metastatic adenocarcinomas. These findings suggest that the ductular cells and small bile duct epithelial cells might have a prolonged survival and might be hepatic progenitor cells. In addition, the bcl-2 protein appears to be a marker of cholangiocarcinoma but not of hepatocellular carcinoma and could help in distinguishing between these two primary liver tumors. 相似文献
62.
63.
Use of the Roche LightCycler instrument in a real-time PCR for Trichomonas vaginalis in urine samples from females and males 总被引:1,自引:0,他引:1
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![点击此处可从《Journal of clinical microbiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Trichomonas vaginalis is the agent of a highly prevalent sexually transmitted infection (STI) that can result in vaginitis, urethritis, and preterm birth. Traditional methods of diagnosis, including wet preparation, can be unreliable. In this study, we describe the adaptation of an existing PCR method for specific detection of T. vaginalis DNA into a rapid real-time PCR assay based on fluorescence resonance energy transfer (FRET) probe chemistry. The FRET-based assay described demonstrated high sensitivity with a detection limit of 1.06 organisms, as well as a high specificity. A total of 253 urine samples collected prospectively from both men and women were tested for T. vaginalis DNA with both the FRET-based assay and a previously validated PCR assay. When the validated PCR assay was used as the "gold standard" and after discrepancies had been resolved, our FRET-based assay demonstrated an analytical sensitivity and specificity of 90.1 and 100%, respectively. Overall results suggest that FRET-based assays can provide rapid, accurate, and high-throughput detection of T. vaginalis and may prove useful in clinical settings and for large-scale screening programs. 相似文献
64.
Penkowa M Keller P Keller C Hidalgo J Giralt M Pedersen BK 《Experimental physiology》2005,90(4):477-486
Exercise induces free oxygen radicals that cause oxidative stress, and metallothioneins (MTs) are increased in states of oxidative stress and possess anti-apoptotic effects. We therefore studied expression of the antioxidant factors metallothionein I and II (MT-I + II) in muscle biopsies obtained in response to 3 h of bicycle exercise performed by healthy men and in resting controls. Both MT-I + II proteins and MT-II mRNA expression increased significantly in both type I and II muscle fibres after exercise. Moreover, 24 h after exercise the levels of MT-II mRNA and MT-I + II proteins were still highly increased and the MT-II mRNA expression reached a 15-fold increase. As expected, immunohistochemical detection of malondialdehyde (MDA) and nitrotyrosine (NITT) showed that formation of free radicals and oxidative stress were clearly increased in exercising muscle peaking shortly after the end of exercise in both type I and II muscle fibres. This is the first report demonstrating that MT-I + II are significantly induced in human skeletal muscle fibres following exercise. As MT-I + II are antioxidant factors that protect various tissues during pathological conditions, the MT-I + II increases post exercise may represent a mechanism whereby contracting muscle fibres are protected against cellular stress and injury. 相似文献
65.
Charlotte
rndal Nils Mandahl Birgitta Carln Helena Willn Johan Wennerberg Sverre Heim Felix Mitelman 《Cancer Genetics and Cytogenetics》1992,60(2):147-151
Near-haploid solid tumors are very rare. In a storiform-pleomorphic malignant fibrous histiocytoma (MFH) of bone, we found three cell populations: one with a near-haploid, a second with a near-diploid, and a third with a near-tetraploid chromosome number. The near-haploid cells had few structural rearrangements: i(12p) and t(13q21q) in one clone, and these two and an additional t(19;?)(p11;?) in another clone. One structurally normal copy of all chromosomes was also present, except that the only chromosome 13 was involved in the t(13q21q). There were also two near-diploid clones, one without the t(19;?) and one with a single copy of this derivative chromosome. This is the first MFH reported to have a near-haploid modal chromosome number, and also the first tumor with i(12p) among bone and soft tissue tumors. 相似文献
66.
The role of histone acetylation in SMN gene expression 总被引:7,自引:0,他引:7
Kernochan LE Russo ML Woodling NS Huynh TN Avila AM Fischbeck KH Sumner CJ 《Human molecular genetics》2005,14(9):1171-1182
67.
68.
We examined the possibility of establishment of patent infections after percutaneous exposure of parasite-naive pigs to 10,000
Oesophagostomum dentatum infective larvae (L3). At 5 weeks after percutaneous exposure the pigs were slaughtered and low numbers of adult O. dentatum were recovered from the large intestine. In addition, exsheathed L3 were intravenously injected into pigs, which resulted in the recovery of fourth-stage larvae (L4) from nodules in the lungs as well as of L4 and adult worms from the large intestine. This study demonstrates the ability of porcine nodular worms to establish in the
large intestine when pigs have been exposed percutaneously to infective larvae. It is possible that the larvae reach the large
intestine by invading blood veins or the lymphatic system at the site of penetration.
Received: 24 February 1998 / Accepted: 13 May 1998 相似文献
69.
Background
Changes in self-concept are an important potential outcome for many interventions for people with long-term conditions. This study sought to identify and evaluate outcome questionnaires suitable for quantifying changes in self-concept in people with long-term conditions, in the context of treatment with acupuncture and Chinese medicine. 相似文献70.
Pernille Mathiesen Tørring Martin Jakob Larsen Charlotte Brasch-Andersen Lotte Nylandsted Krogh Maria Kibæk Lone Laulund Niels Illum Ulrike Dunkhase-Heinl Antje Wiesener Bernt Popp Giuseppe Marangi Tina Duelund Hjortshøj Jakob Ek Ida Vogel Naja Becher Laura Roos Marcella Zollino Christina Ringmann Fagerberg 《European journal of medical genetics》2019,62(2):129-136