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BACKGROUND: Fine needle aspiration biopsy is a well-established method for dijfrrentiation of infective from neoplastic lesions. Varions infective agents, such as mycobacteria, leishmaniasis and microfaria can be diagnosed from aspirates, but there are few case reports on fungal infections in aspirates. Cytologic diagnosis of Aspergillus has occasionally occurred on sputum, pulmonary samples, vaginal secretions, endometrial washings and maxillary sinus specimens. One case of hepatic and subcutaneous masses was diagnosed as Aspergillus by fine needle aspiration and confirmed by culture and histology. CASES: Two cases of subcutaneous aspergillosis were diagnosed by fine needle aspiration and confirmed by culture and histology. CONCLUSION: Fine needle aspiration cytology is a rapid, sensitive and important method of diagnosing Aspergillus and provides a rapid diagnosis, which may be life saving in an immunocompromised patient.  相似文献   
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Remarkable efforts have recently been made in the tissue engineering of heart valves to improve the results of valve transplantations and replacements, including the design of artificial valves. However, knowledge of the cell and molecular biology of valves and, specifically, of valvular interstitial cells (VICs) remains limited. Therefore, our aim has been to determine and localize the molecules forming the adhering junctions (AJs) that connect VICs in situ and in cell culture. Using biochemical and immunolocalization methods at the light- and electron-microscopic levels, we have identified, in man, cow, sheep and rat, the components of VIC-connecting AJs in situ and in cell culture. These AJs contain, in addition to the transmembrane glycoproteins N-cadherin and cadherin-11, the typical plaque proteins α- and β-catenin as well as plakoglobin and p120, together with minor amounts of protein p0071, i.e. a total of five plaque proteins of the armadillo family. While we can exclude the occurrence of desmogleins, desmocollins and desmoplakin, we have noted with surprise that AJs of VICs in cell cultures, but not those growing in the valve tissue, contain substantial amounts of the desmosomal plaque protein, plakophilin-2. Clusters of AJs occur not only on the main VIC cell bodies but are also found widely dispersed on their long filopodia thus forming, in the tissue, a meshwork that, together with filopodial attachments to paracrystalline collagen fiber bundles, establishes a three-dimensional suprastructure, the role of which is discussed with respect to valve formation, regeneration and function. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. The work was supported by grants from the Deutsche Krebshilfe (grant 10-2049-Fr1 to W.W.F.) and the German Ministry for Education and Research (BMBF) in a cooperative research program entitled “Standardization of mesenchymal stem cells for regenerative medicine (START-MSC)”.  相似文献   
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BACKGROUND: Most clinicians read only the abstract of papers in scientific journals. Therefore, it is very important that abstracts contain as much information as possible, to summarize the data succinctly. Our objectives were to evaluate the quality of information in abstracts reporting human fetal outcomes following drug exposure during pregnancy. METHODS: We developed quality criteria based on previous work, modifying them for use with pregnancy outcomes. Quality scores were calculated as present/absent for all of the equally weighted criteria, then expressed as percentages (present/[present + absent]). We examined a random sample of 100 abstracts obtained through searches of MEDLINE, EMBASE, and the Web of Science databases from 1990 to 2005. Average quality scores were compared across designs (cohort, case-control, meta-analysis, and mixed design) Using Kruskal-Wallis ANOVA and structured/unstructured formats using Student's t test. RESULTS: The overall average quality was 59.2% +/- 14% (median, 61.5%; range, 15.4-83.3%). Quality was not significantly different across designs (P = .16) or between structured and unstructured abstracts (P = .44). Quality scores increased over time (Rho = 0.23, P = .02). Most frequently absent were baseline risk (94%), drug dose (91%), nonsignificant P values (72%), confounders (69%), significant P values (57%), and risk difference (48%). CONCLUSIONS: Abstracts provide insufficient information, particularly baseline risk values, for readers to make evidence-based decisions regarding drug use during pregnancy. Efforts need to be made to improve the quality of abstracts and include critical information such as baseline risk.  相似文献   
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Lithium, a drug of choice in bipolar affective disorders, also affects the metabolism and cell proliferation in a diverse array of organisms. In this study, we investigated the effect of lithium on bombesin-mediated function in excretion and growth of the pancreas and the salivary glands. The weight, protein content, amylase concentration and salivary flow rate of the pancreas, parotid and the submandibular glands were determined in male Wistar rats after consumption of either water or lithium chloride (600 mg/l) for 14 days and each group received s.c. injection of either saline or bombesin (10 microg/kg) during the last 4 days of experiment. Our results revealed that administration of bombesin in lithium-treated group not only suppressed pancreas and parotid weight augmentation due to bombesin, but also significantly decreased pancreas growth. Chronic lithium consumption significantly inhibited the protein content augmentation due to bombesin in the salivary glands. Getting bombesin, as well as saline in lithium-treated group, resulted in notable decrease in salivary protein content. Protein content of pancreatic gland increased considerably in the bombesin-injected groups either treated with saline or lithium. In conclusion, the stimulatory effect of bombesin on the growth and protein content of the pancreas and the salivary gland was inhibited by lithium. Lithium seems to be a potent inhibitor of growth factors induced by bombesin probably through inhibiting phosphatidylinositol 4,5,bisphosphate hydrolysis.  相似文献   
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Uropathogenic Escherichia coli (UPEC) as the most important bacterial agent of urinary tract infections (UTIs) encompasses a wide treasure of virulence genes and factors. In due to this default,...  相似文献   
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Wnt signaling is crucial for a variety of biological processes, including body axis formation, planar polarity, stem cell maintenance and cellular differentiation. Therefore, targeted manipulation of Wnt signaling in vivo would be extremely useful. By applying chemical inducer of dimerization (CID) technology, we were able to modify the Wnt co-receptor, low-density lipoprotein (LDL)-receptor-related protein 5 (LRP5), to generate the synthetic ligand inducible Wnt switch, iLRP5. We show that iLRP5 oligomerization results in its localization to disheveled-containing punctate structures and sequestration of scaffold protein Axin, leading to robust β-catenin-mediated signaling. Moreover, we identify a novel LRP5 cytoplasmic domain critical for its intracellular localization and casein kinase 1-dependent β-catenin signaling. Finally, by utilizing iLRP5 as a Wnt signaling switch, we generated the Ubiquitous Activator of β-catenin (Ubi-Cat) transgenic mouse line. The Ubi-Cat line allows for nearly ubiquitous expression of iLRP5 under control of the H-2K(b) promoter. Activation of iLRP5 in isolated prostate basal epithelial stem cells resulted in expansion of p63(+) cells and development of hyperplasia in reconstituted murine prostate grafts. Independently, iLRP5 induction in adult prostate stroma enhanced prostate tissue regeneration. Moreover, induction of iLRP5 in male Ubi-Cat mice resulted in prostate tumor progression over several months from prostate hyperplasia to adenocarcinoma. We also investigated iLRP5 activation in Ubi-Cat-derived mammary cells, observing that prolonged activation results in mammary tumor formation. Thus, in two distinct experimental mouse models, activation of iLRP5 results in disruption of tissue homeostasis, demonstrating the utility of iLRP5 as a novel research tool for determining the outcome of Wnt activation in a precise spatially and temporally determined fashion.  相似文献   
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