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Milena Soares Santos Guilherme de Sousa Ribeiro Tainara Queiroz Oliveira Renan Cardoso Nery Santos Edilane Gouveia Kátia Salgado Daniele Takahashi Cleuber Fontes Leila Carvalho Campos Mitermayer Galvão Reis Albert Icksang Ko Joice Neves Reis 《International journal of infectious diseases》2009,13(4):456-461
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对32例的尿结石采用化学定量分析法进行化学成分分析,利用材料力学原理和方 法测定密度、硬度和抗压强度,并对其中13例的尿结石作体外碎石试验。结果表明碎石所需 冲击次数与结石成分有关,尤其是草酸钙结石所需冲击次数明显增加;冲击次数与结石物理特 性有关,随结石硬度增加而增加。因此,检测尿结石理化性质在体外冲击波碎石中具有重要意 义。 相似文献
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David D. Dean Zvi Schwartz Ofelia E. Muniz Ruben Gomez Larry D. Swain David S. Howell Barbara D. Boyan 《Calcified tissue international》1992,50(4):342-349
Summary This study examined the presence of extracellular matrix processing enzymes in matrix vesicles produced by rat costochondral resting zone and growth zone chondrocytes in culture. Optimum procedures for the extraction of each enzyme activity were determined. Enzyme activity associated with chondrocyte plasma membrane microsomes was used for comparison. There was a differential distribution of the enzyme activities related to the cartilage zone from which the cells were isolated. Acid and neutral metalloproteinase (TIMP), plasminogen activator, and betaglucuronidase were highest in the growth zone chondrocyte (GC) membrane fractions when compared with matrix vesicles and plasma membranes isolated from resting zone chondrocyte (RC) cultures. There was a threefold enrichment of total and active acid metalloproteinase in GC matrix vesicles, whereas no enrichment in enzyme activity was observed in RC matrix vesicles. Total and active neutral metalloproteinase were similarly enriched twofold in GC matrix vesicles. TIMP, plasminogen activator, and betaglucuronidase activities were highest in the plasma membranes of both cell types. No collagenase, lysozyme, or hyaluronidase activity was found in any of the membrane fractions. The data indicate that matrix vesicles are selectively enriched in enzymes which degrade proteoglycans. The highest concentrations of these enzymes are found in matrix vesicles produced by growth zone chondrocytes, suggesting that this may be a mechanism by which the more differentiated cell modulates the matrix for calcification. 相似文献
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C Joseph Muniz Arthur C Fleischer Edwin F Donnelly Murray J Mazer 《Journal of ultrasound in medicine》2002,21(2):129-133
OBJECTIVE: To assess the accuracy of three-dimensional color Doppler sonography and uterine artery arteriography in depicting changes in fibroid vascularity before and after embolization. METHODS: Preembolization and postembolization three-dimensional color Doppler sonography and selective uterine artery arteriography were retrospectively compared in 15 patients who underwent uterine artery embolization for treatment of symptomatic fibroids. Three-dimensional color Doppler sonography was performed by using a scanner with color power angiographic imaging capability. Vascularity was quantified by using an estimation of power-weighted pixel density as described by our group in previously published studies. Uterine artery arteriography was performed by using a standard selective microcatheter embolization technique. For purposes of comparison, fibroids were classified as either hypervascular or hypovascular relative to myometrial vascularity before and minutes to several hours after uterine artery embolization. Changes in fibroid vascularity (i.e., from hypervascular to hypovascular) as depicted by three-dimensional color Doppler sonography were compared with those shown on uterine artery arteriography and classified as being in agreement or disagreement. RESULTS: In 13 (87%) of 15 patients there was agreement; in 2 (13%) of 15 there was disagreement. In both cases of disagreement, three-dimensional color Doppler sonography showed collateral flow not depicted by uterine artery arteriography The mean reduction in quantitated vascularity after uterine artery embolization was 44% (range, 19%-78%). CONCLUSIONS: Three-dimensional color Doppler sonography accurately depicts fibroid vascularity and in some cases can reveal collateral flow not depicted by uterine artery arteriography. 相似文献
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Anna Tesei Marco Rosetti Paola Ulivi Francesco Fabbri Laura Medri Ivan Vannini Manlio Bolla Dino Amadori Wainer Zoli 《Journal of translational medicine》2007,5(1):52
Background
Despite numerous studies aimed at verifying the antitumor activity of nitric oxide-releasing nonsteroidal antiflammatory drugs (NO-NSAIDs), little is known about the molecular targets responsible for their antineoplastic properties. In the present study, we investigated the mechanisms underlying the cytotoxicity of NCX 4040, a novel NO-aspirin with promising antineoplastic action, in in vitro human colon cancer models. 相似文献10.
Trypanosoma evansi (Trypanosomatidae, Kinetoplastida) is a salivarian trypanosomatid that infects eight mammal orders spread over America, Europe and Asia. In Brazil, T. evansi is the etiological agent of Mal de Cadeiras, a horse disease very often described in the region known as Pantanal do Mato Grosso. Few data concerning the genetic diversity and biology of subpopulations of T. evansi that circulate in Brazil are available. The factors that modulate the interaction of this parasite with its hosts also remain to be elucidated. Here we evaluated the course of experimental infection of six T. evansi isolates derived from domestic and wild animals in Swiss-Webster mice and three Mus musculus lineages. The follow-up included biological, immunological as well as biochemical and hematological parameters. The same isolates as well as three others were characterized by pulsed-field electrophoresis. Our results showed that T. evansi isolates displayed significant differences regarding behavior and morbidity patterns in the distinct mouse lineages. Nevertheless, these differences could not be correlated with pulsed-field electrophoresis profiles. Indeed, concerning this molecular marker, only microheterogeneity was observed. Moreover, we observed that the outcome of the infection is defined by both host genetic background and peculiarities (virulence factors) of the distinct T. evansi isolates. Anemia and hypoglycemia were the only features that could be observed in all mouse lineages, independently of the inoculated T. evansi subpopulation. In addition, our data also show that Mus musculus is a suitable model host for the study of the different pathogenetic features of T. evansi infection. 相似文献