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1.
Jaroslav Barto Ignc Capek Ondrej uoliak Viera Jurani
ov 《Macromolecular chemistry and physics.》1978,179(12):2937-2943
The rate of the polymerization of vinyl monomers photoinitiated (at λ = 365 nm) by benzoylated polystyrene in N,N-dimethylformamide (DMF) decreases in the sequence vinyl acetate>acrylonitrile>methyl methacrylate ? styrene ≈ 0 and is related to the rate constant of propagation of the mentioned monomers. In addition to DMF, aromatic hydrocarbons (benzene, toluene, p-xylene), cyclohexane and tetrahydrofuran were employed as hydrogen donors. The maximum polymerization rate was achieved in the system containing p-xylene; the system with benzene turned out inefficient for the initiation of acrylonitrile polymerization. Turbidimetric titration of a soluble fraction of the acrylonitrile polymerization in DMF in presence of benzoylated polystyrene showed that the soluble fraction does not contain graft copolymers of benzoylated polystyrene with acrylonitrile. It is assumed, however, that the polyacrylonitrile in the insoluble fraction is bound to benzoylated polystyrene in the form of graft copolymers. 相似文献
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We present a unique case of urothelial carcinoma of the right renal pelvis. It occurred in a 58-year-old woman. The tumor was located in the renal pelvis with extension into the adjacent renal medulla and cortex. Two years after surgical excision the patient is free of recurrence and metastasis. The tumor was well demarcated, without capsule, firm, solid, and whitish on the cut surface. It was 3x4 cm in largest diameter and without signs of necroses and hemorrhages. The tumor did not infiltrate the ureter. Histologically the predominant pattern of the tumor was adenocarcinomatous differentiation, and only very rare foci of urothelial carcinoma composed of typical transitional cells were found. No signs of intestinal type of metaplasia and adenocarcinoma, changes similar to the cystitis cystica or cystitis glandularis, were found in the tumor or in its vicinity. Most of the tumor looked like solid nests composed of cells with intracytoplasmic lumens. The resulting appearance was that of typical signet-ring cell change. These solid nests were usually surrounded by columnar epithelium, which in many areas formed papillary structures. A very striking feature was formation of collagen spherules. Small collagen spherules were often surrounded by a layer of the neoplastic cells so that collagenous rosettes were formed. In some areas these collagenous spherules clustered together so that they formed areas of collagenous spherulosis. The collagen in the spherules reacted positively with collagen IV. Ultrastructurally these spherules were formed by basal membrane-like material. Intracytoplasmic lumens of the signet-ring cell change were endowed by slender microvilli at ultrastructural level. 相似文献
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Mixed epithelial and stromal tumors of the kidney. A report of 22 cases 总被引:16,自引:0,他引:16
Michal M Hes O Bisceglia M Simpson RH Spagnolo DV Parma A Boudova L Hora M Zachoval R Suster S 《Virchows Archiv : an international journal of pathology》2004,445(4):359-367
Mixed epithelial and stromal tumor of the kidney (MESTK) is a recently described subset of renal neoplasm that tends to occur in middle-aged and older women and is characterized by a distinctive histological appearance. To further characterize this lesion, we report the clinicopathological and immunohistochemical features of 22 additional cases from our institutional files. Grossly, the tumors ranged in size from 1 cm to 14 cm (mean 6.7 cm), were well circumscribed but unencapsulated, and showed a cystic cut surface. The tumors were composed of a spindle cell proliferation that resembled ovarian stroma, as well as an epithelial component lining the cystic structures, which usually consisted of flat to hobnailed cells typical of collecting-duct epithelium. Areas displaying features of Müllerian differentiation were also documented in 6 cases, including epithelium of endometrioid, tubal, clear cell and squamous cell type as well as one case showing an architecture that closely resembled Müllerian adenofibroma and adenosarcoma. Follow-up in 14 patients (average 4.4 years) showed no evidence of recurrence or metastasis. We believe these tumors represent the renal counterpart of similar mixed epithelial and stromal neoplasms occurring in the biliary tract and pancreas, which is also characterized by cystic structures lined by epithelium, admixed with ovarian-type stroma. The differential diagnosis for these tumors includes cystic nephroma and cystic partially differentiated nephroblastoma, which we believe to represent clinically and morphologically distinct entities from MESTK. In particular, the distinction from cystic nephroma in adult male patients is emphasized, and two cases of this entity are included in the study for comparison. 相似文献
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Gabriella Sistilli Veronika Kalendova Tomas Cajka Illaria Irodenko Kristina Bardova Marina Oseeva Petr Zacek Petra Kroupova Olga Horakova Karoline Lackner Amalia Gastaldelli Ondrej Kuda Jan Kopecky Martin Rossmeisl 《Nutrients》2021,13(2)
Preclinical evidence suggests that n-3 fatty acids EPA and DHA (Omega-3) supplemented as phospholipids (PLs) may be more effective than triacylglycerols (TAGs) in reducing hepatic steatosis. To further test the ability of Omega-3 PLs to alleviate liver steatosis, we used a model of exacerbated non-alcoholic fatty liver disease based on high-fat feeding at thermoneutral temperature. Male C57BL/6N mice were fed for 24 weeks a lard-based diet given either alone (LHF) or supplemented with Omega-3 (30 mg/g diet) as PLs (krill oil; ω3PL) or TAGs (Epax 3000TG concentrate; ω3TG), which had a similar total content of EPA and DHA and their ratio. Substantial levels of TAG accumulation (~250 mg/g) but relatively low inflammation/fibrosis levels were achieved in the livers of control LHF mice. Liver steatosis was reduced by >40% in the ω3PL but not ω3TG group, and plasma ALT levels were markedly reduced (by 68%) in ω3PL mice as well. Krill oil administration also improved hepatic insulin sensitivity, and its effects were associated with high plasma adiponectin levels (150% of LHF mice) along with superior bioavailability of EPA, increased content of alkaloids stachydrine and trigonelline, suppression of lipogenic gene expression, and decreased diacylglycerol levels in the liver. This study reveals that in addition to Omega-3 PLs, other constituents of krill oil, such as alkaloids, may contribute to its strong antisteatotic effects in the liver. 相似文献
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Kamyar Kalantar-Zadeh Philip Kam-Tao Li Ekamol Tantisattamo Latha Kumaraswami Vassilios Liakopoulos Siu-Fai Lui Ifeoma Ulasi Sharon Andreoli Alessandro Balducci Sophie Dupuis Tess Harris Anne Hradsky Richard Knight Sajay Kumar Maggie Ng Alice Poidevin Gamal Saadi Allison Tong 《Nefrología : publicación oficial de la Sociedad Espa?ola Nefrologia》2021,41(2):95-101
Living with chronic kidney disease (CKD) is associated with hardships for patients and their care-partners. Empowering patients and their care-partners, including family members or friends involved in their care, may help minimize the burden and consequences of CKD related symptoms to enable life participation. There is a need to broaden the focus on living well with kidney disease and re-engagement in life, including an emphasis on patients being in control. The World Kidney Day (WKD) Joint Steering Committee has declared 2021 the year of “Living Well with Kidney Disease” in an effort to increase education and awareness on the important goal of patient empowerment and life participation. This calls for the development and implementation of validated patient-reported outcome measures to assess and address areas of life participation in routine care. It could be supported by regulatory agencies as a metric for quality care or to support labelling claims for medicines and devices. Funding agencies could establish targeted calls for research that address the priorities of patients. Patients with kidney disease and their care-partners should feel supported to live well through concerted efforts by kidney care communities including during pandemics. In the overall wellness programme for kidney disease patients, the need for prevention should be reiterated. Early detection with a prolonged course of wellness despite kidney disease, after effective secondary and tertiary prevention programmes, should be promoted. WKD 2021 continues to call for increased awareness of the importance of preventive measures throughout populations, professionals, and policy makers, applicable to both developed and developing countries. 相似文献
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Mark Korthals Laura Tech Kristina Langnaese Anna Gottfried Johannes Hradsky Ulrich Thomas Ana Claudia Zenclussen Monika C. Brunner-Weinzierl Kerry Tedford Klaus-Dieter Fischer 《European journal of immunology》2021,51(3):594-602
The amplitude and duration of Ca2+ signaling is crucial for B-cell development and self-tolerance; however, the mechanisms for terminating Ca2+ signals in B cells have not been determined. In lymphocytes, plasma membrane Ca2+ ATPase (PMCA) isoforms 1 and 4 (PMCA1 and PMCA4, aka ATP2B1 and ATP2B4) are the main candidates for expelling Ca2+ from the cell through the plasma membrane. We report here that Pmca4 (Atp2b4) KO mice had normal B-cell development, while mice with a conditional KO of Pmca1 (Atp2b1) had greatly reduced numbers of B cells, particularly splenic follicular B cells, marginal zone B cells, and peritoneal B-1a cells. Mouse and naïve human B cells showed only PMCA1 expression and no PMCA4 by western blot, in contrast to T cells, which did express PMCA4. Calcium handling was normal in Pmca4−/− B cells, but Pmca1 KO B cells had elevated basal levels of Ca2+, elevated levels in ER stores, and reduced Ca2+ clearance. These findings show that the PMCA1 isoform alone is required to ensure normal B-cell Ca2+ signaling and development, which may have implications for therapeutic targeting of PMCAs and Ca2+ in B cells. 相似文献