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61.
Regula J Hennig E Burzykowski T Orlowska J Przytulski K Polkowski M Dziurkowska-Marek A Marek T Nowak A Butruk E Ostrowski J 《Digestion》2003,67(1-2):25-31
BACKGROUND: Although Helicobacter pylori is a significant etiologic factor of peptic ulcer disease, it remains unknown why ulcers develop only in the minority of infected individuals. AIM: The aim of this cross-sectional study was to evaluate the association between the presence of duodenal ulcer in H. pylori-infected patients and different risk factors. METHODS: A total of 122 H. pylori-infected patients were enrolled; 79 had duodenal ulcer and 43 gastritis. Univariate analysis was conducted using either Fisher's exact test or exact Cochrane-Armitage trend test. In multivariate analysis the logistic model was used. RESULTS: Univariate analysis indicated six factors (male sex, smoking, antral H. pylori density, CAGA presence in antrum, and VACA s1a presence in antrum and corpus). Four factors (sex, smoking-alcohol index, H. pylori density index, and CAGA index) were found to be significant in multivariate analysis. The best model predicting duodenal ulcer included male sex, smoking, presence of H. PYLORI on histopathology in antrum and CAGA presence in corpus. CONCLUSION: Although several risk factors were significantly associated with duodenal ulcer, we failed in the identification of either a single risk factor or a set of factors that can unequivocally differentiate patients with ulcer from those with gastritis. 相似文献
62.
Tomasz Cytlak Monika Skibiska Patrycja Kaczmarek Marcin Ka
mierczak Magdalena Rapp Maciej Kubicki Henryk Koroniak 《RSC advances》2018,8(22):11957
Direct conversion of the α-hydroxyl group by para-toluenesulfonamide to yield α-(N-tosyl)aminophosphonates is reported. α-Aminophosphonates 23a,b–37a,b were obtained from the corresponding α-hydroxyphosphonates 6a,b–21a,b in the presence of K2CO3, via the retro-Abramov reaction of the appropriate aldehydes, 1–5. The subsequent formation of imines with simultaneous addition of diethyl phosphite provided access to the α-sulfonamide phosphonates 23a,b–37a,b with better diastereoselectivity than in the case of the Pudovik reaction. The mechanism for this transformation is proposed herein. When Cbz N-protected aziridine 9a,b and phenylalanine analogue 12a,b were exploited, intramolecular substitution was observed, leading to the corresponding epoxide 38 as the sole product, or oxazolidin-2-one 39 as a minor product. Analogous substitution was not observed in the case of proline 18a,b and serine 21a,b derivatives.The reaction mechanism and diastereoselectivity of the direct transformation of α-hydroxyphosphonates 6a,b–21a,b by para-toluenesulfonamide, yielding α-(N-tosyl)aminophosphonates 23a,b–37a,b under K2CO3 conditions are presented. 相似文献
63.
Maciej Dzwonek Dominika Zaubiniak Piotr Pitek Grzegorz Cichowicz Sylwia Mczynska-Wielgosz Tomasz Stpkowski Marcin Kruszewski Agnieszka Wickowska Renata Bilewicz 《RSC advances》2018,8(27):14947
Modification of ultrasmall gold nanoparticles (AuNPs) with the lipoic acid derivative of folic acid was found to enhance their accumulation in the cancer cell, as compared to AuNPs without addressing units. The application of lipoic acid enabled the control of the gold nanoparticle functionalities leading to enhanced solubility and allowing for attachment of both the folic acid and the cytotoxic drug, doxorubicin. More robust attachment of doxorubicin to the nanoparticle through the amide bond resulted in toxicity comparable with that of the drug alone, opening a new perspective for designing more potent, but less toxic nanopharmaceuticals. The increased uptake was accompanied by pronounced nuclear accumulation and observable cytotoxicity. Doxorubicin binding via covalent amide bonds enhanced stability of the whole drug vehicle and provided much better control over doxorubicin release in the cell environment, as compared to physical adsorption or pH sensitive bonding commonly used for anthracycline carriers. Confocal microscopy revealed that the bond was stable in the cytoplasm for 22 h. The ability to slow down the rate of drug release may be crucial for the application in sustained anticancer drug delivery. Biological analyses performed using MTT assay and confocal microscopy confirmed that the ultrasmall AuNPs with the lipoic acid derivative of folic acid exhibit relatively low cytotoxicity, however when loaded with a chemotherapeutic, they cause a significant reduction in the cell viability.Modification of ultrasmall gold nanoparticles (AuNPs) with the lipoic acid derivative of folic acid was found to enhance their accumulation in the cancer cell, as compared to AuNPs without addressing units. 相似文献
64.
Mak Lung-Yi Huang Qi Wong Danny Ka-Ho Stamm Luisa Cheung Ka-Shing Ko Kwan-Lung Yan Ran Ouyang Lea Fung James Seto Wai-Kay Yuen Man-Fung 《Journal of gastroenterology》2021,56(5):479-488
Journal of Gastroenterology - We aimed to assess whether residual hepatitis B virus (HBV) viraemia is associated with HCC development. This is a case–control study of 104 patients [52 HCC and... 相似文献
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66.
Szleszkowski Łukasz Kadej Marcin Ogórek Rafał Thannhäuser Agata Dobrowolski Michał A. Jurek Tomasz 《International journal of legal medicine》2022,136(6):1829-1840
International Journal of Legal Medicine - It is extremely rare for table salt to be used to preserve a dead body in criminal cases. In the case presented here, after the death of his 85-year-old... 相似文献
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70.
Yu Ben C. L. Mak Winnie W. S. Chio Floria H. N. 《Social psychiatry and psychiatric epidemiology》2021,56(3):401-408
Social Psychiatry and Psychiatric Epidemiology - Family has been found to have an influential role on clinical and recovery outcomes of people with schizophrenia. While recovery-oriented services... 相似文献