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排序方式: 共有2199条查询结果,搜索用时 31 毫秒
1.
Differential mortality: some comparisons between England and Wales, Finland and France, based on inequality measures 总被引:4,自引:0,他引:4
Inequalities in mortality between social classes or socioeconomic groups were compared in three European countries, using similar sources of data from large national cohort studies. People registered at a census in 1971 (1975 for France) or a sample of them, were followed until 1980 or 1981. The Gini coefficient, a measure widely used in economics, allowed the comparison of various situations involving different numbers and group sizes. It was applied to age groups 35-44, and 45-54 for men only. According to this measure, inequalities were of the same order in England and Wales and Finland, and greater in France. Differences between the three countries concerning the principal causes of death leading to inequalities were cardiovascular diseases in England and Wales, accidents and cardiovascular diseases in Finland, and cancer and cirrhosis in France. 相似文献
2.
C. Ferrero-Vacher I. Sudaka D. Jambou D. Vanhaeke F. Fischer J. Bayle 《Hematology and Cell Therapy》1997,39(3):149-158
An evaluation of the new automated hematology analyzer was performed in comparison with the Coulter STKS on 1,694 blood samples coming from the different departments of Nice University Hospital. The Cobas Vega showed very satisfactory results in terms of repeatability, reproducibility and linearity. Correlation with the STKS was excellent with the exception of the following parameters: red blood cell distribution index and the absolute values for eosinophils and basophils. Two qualities were particularly appreciable: absence of leukocyte carryover, and stability of the complete blood count and leukocyte differential count over a long period. Analysis of qualitative flags showed that the overall blood smear review rate was 47% for the Cobas Vega, not forgetting that optical microscopy detects 37% of all abnormalities. The STKS’s review rate was 49.5%. Flags commonly concerned the granulocytic lineage, 61% for the STKS and 48% for the Vega, with a false positive rate of 43.4% for the STKS compared with 22% for the Vega. The opposite phenomenon was observed with the flag for atypical lymphocytes which represented 11% of flags for the STKS and 25.6% for the Vega, with a false positive rate of 25.5% for the STKS and 34% for the Cobas Vega. This may be explained by the fact that lymphocyte abnormalities sometimes generated “granulocytic” flags on the STKS. Studies of the false negative rate carried out using light microscopy on 505 blood samples without flags on either system, detected the presence of a slight myelemia, and a few hyperbasophilic lymphocytes or plasmocytes in 18.6% of all cases. Finally, the Cobas Vega’s practicality was greatly appreciated and there was no trouble with breakdowns throughout the whole period of its use. 相似文献
3.
J. F. Bergmann O. Chassany P. J. Guillausseau M. Bayle S. Chagnon C. Caulin J. R. Sallenave 《European journal of clinical pharmacology》1992,43(2):121-124
Summary The aim of the study was to use a novel combination of two methods for the simultaneous evaluation of two effects of oral cisapride in 10 diabetic patients with autonomic neuropathy; gastric emptying time was measured by following radio-opaque markers and orocaecal transit time by the sulphasalazine-sulphapridine method. The study was of double-blind, randomized, placebo-controlled, cross-over design.It was possible to evaluate the effect of a prokinetic drug on gastric emptying and orocaecal transit times using these two noninvasive techniques at the same time. Cisapride significantly reduced both the gastric emptying (1.2 h versus 2.1 h) and orocaecal tansit (5.9 h versus 7.7 h) times. 相似文献
4.
Biocompatibility studies of the Anaconda stent-graft and observations of nitinol corrosion resistance. 总被引:3,自引:0,他引:3
Robert Guidoin Yvan Douville Michel F Baslé Martin King Georgi R Marinov Amidou Traoré Ze Zhang Fabien Guillemot Guy Dionne Ruwan Sumanasinghe André-Pierre Legrand Marie-France Guidoin Marie-Christine Porté-Durrieu Charles Baquey 《Journal of endovascular therapy》2004,11(4):385-403
PURPOSE: To validate the deployment, in vivo performance, biostability, and healing capacity of the Anaconda self-expanding endoprosthesis in a canine aortic aneurysm model. METHODS: Aneurysms were surgically created in 12 dogs by sewing a woven polyester patch onto the anterior side of the thoracic or abdominal aorta. Anaconda prostheses were implanted transfemorally for prescheduled periods (1 or 3 months). Aneurysm exclusion and stent-graft patency were monitored angiographically. Healing was assessed with histological analysis and scanning electron microscopy (SEM). Textile analysis determined the physical and chemical stability of the woven polyester material, while the biostability of the nitinol wires was evaluated with SEM and spectroscopy. RESULTS: All prostheses were intact at explantation. After 1 month, endothelial-like cells were migrating in a discontinuous manner both proximally and distally over the internal collagenous pannus at the device-host boundary. After 3 months, endothelialization had reached the midsections of the devices, with a thicker collagenous internal capsule. Patches of endothelial-like cells were sharing the luminal surface with thrombotic deposits. However, the wall of the device at the level of the aneurysm was generally poorly healed, with multiple thrombi scattered irregularly over the luminal surface. The polyester fabric was intact except for some filaments that were ruptured adjacent to the sutures and some abrasion caused by the nitinol wires. No evidence of corrosion was found on the nitinol stents. CONCLUSIONS: This Anaconda stent-graft has demonstrated its ability to exclude arterial aneurysms. The device used in this study was an experimental prototype, and the manufacturer has incorporated new immobilization features into the model for clinical use. The constituent materials appear to be suitable in terms of biocompatibility, biofunctionality, and short-term durability. 相似文献
5.
Rapid detection of Pneumocystis carinii in bronchoalveolar lavage specimens from human immunodeficiency virus-infected patients: use of a simple DNA extraction procedure and nested PCR.
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M Rabodonirina D Raffenot L Cotte A Boibieux M Mayenon G Bayle F Persat F Rabatel C Trepo D Peyramond M A Piens 《Journal of clinical microbiology》1997,35(11):2748-2751
We report on the development of a rapid nested PCR protocol for the detection of Pneumocystis carinii DNA in bronchoalveolar lavage (BAL) specimens in which the protocol included the use of a commercially available DNA extraction kit (GeneReleaser). GeneReleaser enabled us to obtain amplification-ready DNA within 20 min without requiring the purification of the DNA. The nested PCR was performed with the primers pAZ102-E, pAZ102-H, and pAZ102-L2 (A. E. Wakefield, F. J. Pixley, S. Banerji, K. Sinclair, R. F. Miller, E. R. Moxon, and J. M. Hopkin, Lancet 336:451-453, 1990.). Results were obtained in about 4 h with the adoption of denaturation, annealing, and extension steps shortened to 20 seconds. The sensitivity of the nested PCR was tested with a P. carinii cyst suspension and was found to be less than one cyst (one to eight nuclei). The detection limit was the same with the use of GeneReleaser or proteinase K-phenol chloroform for DNA extraction. The nested PCR assay was prospectively compared with staining with Giemsa and methenamine silver stains for the detection of P. carinii in 127 BAL samples from 105 human immunodeficiency virus-infected patients investigated for acute respiratory illness. Twenty-five BAL specimens (20%) were positive by staining and the nested PCR and 25 (20%) were negative by staining and positive by the nested PCR. These 25 BAL specimens with conflicting results were obtained from 23 patients, 82% of whom were receiving prophylactic therapy against P. carinii pneumonia (PCP). Only two patients were diagnosed with possible PCP. The final diagnosis was not PCP for 20 patients who were considered to be colonized or to have a low level of infection. This colonization is not of clinical importance but is of epidemiological importance. Our rapid, simple, and sensitive amplification protocol may be performed in clinical laboratories for the routine diagnosis of PCP with BAL specimens. 相似文献
6.
Differential expression of extracellular matrix metalloproteinase inducer (CD147) in normal and ulcerated corneas: role in epithelio-stromal interactions and matrix metalloproteinase induction 总被引:12,自引:0,他引:12
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Gabison EE Mourah S Steinfels E Yan L Hoang-Xuan T Watsky MA De Wever B Calvo F Mauviel A Menashi S 《The American journal of pathology》2005,166(1):209-219
Extracellular matrix metalloproteinase inducer (EMMPRIN) was originally identified on the tumor cell surface as an inducer of matrix metalloproteinase (MMP) production in neighboring fibroblasts. Here we demonstrate a role for EMMPRIN in MMP induction during corneal wound healing. MMP and EMMPRIN expression was analyzed in normal and ulcerated human corneas, as well as in corneal epithelial and stromal cells in culture using confocal microscopy, zymography, immunoblots, and real-time polymerase chain reaction. In normal cornea EMMPRIN was predominantly expressed in the epithelium but was markedly induced in the anterior stroma of ulcerated corneas. This coincided with MMP-2 induction that co-localized with EMMPRIN at the epithelio-stromal boundary. The role of epithelial-stromal interaction in MMP induction was investigated in an in vitro co-culture system and demonstrated an induction and co-localization of EMMPRIN and MMP-2 in the fibroblasts at the interface with epithelial cells. Direct contact of fibroblasts with EMMPRIN-containing purified epithelial cell membranes also induced MMP-1, MMP-2, and EMMPRIN and this was inhibited by a blocking anti-EMMPRIN antibody, suggesting that EMMPRIN was primarily responsible for this induction. These findings, and the up-regulation of EMMPRIN by epidermal growth factor and transforming growth factor-beta, demonstrate a role for EMMPRIN in wound healing and suggest that sustained local up-regulation of EMMPRIN and MMPs in chronic situations in which healing is delayed may lead to excessive matrix degradation and corneal melts. 相似文献
7.
Hfq-dependent regulation of OmpA synthesis is mediated by an antisense RNA 总被引:17,自引:1,他引:17
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Udekwu KI Darfeuille F Vogel J Reimegård J Holmqvist E Wagner EG 《Genes & development》2005,19(19):2355-2366
This paper shows that the small RNA MicA (previously SraD) is an antisense regulator of ompA in Escherichia coli. MicA accumulates upon entry into stationary phase and down-regulates the level of ompA mRNA. Regulation of ompA (outer membrane protein A), previously attributed to Hfq/mRNA binding, is lost upon deletion of the micA gene, whereas overexpression of MicA inhibits the synthesis of OmpA. In vitro, MicA binds to the ompA mRNA leader. Enzymatic and chemical probing was used to map the structures of MicA, the ompA mRNA leader, and the complex formed upon binding. MicA binding generates a footprint across the ompA Shine-Dalgarno sequence, consistent with a 12 + 4 base-pair interaction, which is additionally supported by the effect of mutations in vivo and by bioinformatics analysis of enterobacterial micA/ompA homolog sequences. MicA is conserved in many enterobacteria, as is its ompA target site. In vitro toeprinting confirmed that binding of MicA specifically interferes with ribosome binding. We propose that MicA, when present at high levels, blocks ribosome binding at the ompA translation start site, which-in line with previous work-secondarily facilitates RNase E cleavage and subsequent mRNA decay. MicA requires the presence of the Hfq protein, although the mechanistic basis for this remains unclear. 相似文献
8.
Different hormones (thymulin, thymosin alpha 1, vasopressin), antigenic markers of cortical and subcapsular/medullary thymic areas and tumour associated antigens were studied on paraffin or frozen section and cultures of human epithelial thymic tumours ('thymomas'). Thymulin, thymosin alpha 1 and for the first time vasopressin are found in most tumours. The epithelial cells of five 'thymomas' had markers of both cortical (TE3) and subcapsular/medullary thymic regions (A2B5 and/or TE4 and/or anti-p19). Leu-7, a marker of subcapsular epithelial cells was positive only in two tumours. The histological classification into cortical and medullary tumours does not correspond to our immunofluorescence results. The presence of these markers does not support the theory of different embryologic origin of the cortical and subcapsular/medullary epithelial cells. Transferrin receptors were detected on only some epithelial cells of thymic 'carcinomas'. Adenocarcinoma related antigen and carcino embryonic antigen only stained a few epithelial cells of all the tumours. There is no expected correlation between the presence of epidermal growth factor receptors on cell membranes and the number of proliferative cells stained by the anti-Ki67 antibodies. Immunostainings were heterogeneous according to the epithelial thymic tumours, independent of histological classification and not yet useful for prognosis. 相似文献
9.
Anti-thymosin alpha 1 monoclonal antibodies recognized, on immunoblots, 1 to 2 bands corresponding to molecules of 34 and 35 Kd when using aqueous extracts of thymus, spleen, kidney, liver, brain, pituitary and adrenal glands from rats or mice. Anti-bovine thymopoietin polyclonal antibodies, in the same conditions, labelled analogous 34, 35 and 35.5 Kd molecules in brain and thymus extracts but also a 40 Kd molecules in thymus and a 90 Kd in brain extracts. Anti-synthetic thymulin monoclonal antibodies recognized irregularly and poorly a 52 Kd molecule from thymus and brain extracts. These results suggest that thymopoietin, thymulin and specially Thymosin alpha 1 are first synthesized in large precursors. Finally, other organs seem capable of synthesizing thymosin alpha 1 and probably thymopoietin, but for thymulin, the results are too irregular to conclude. 相似文献
10.