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排序方式: 共有10000条查询结果,搜索用时 46 毫秒
991.
992.
Linda Piapan Elena Mazzolini Marco Tomietto Fabio Barbone Francesca Larese Filon 《La Medicina del lavoro》2021,112(6):422
Background:During major epidemic outbreaks, the preparedness of public health systems is challenged and healthcare workers (HCWs) are at the frontline. Italy was among the first- and worst-hit countries by COVID-19.Aim:To analyze the prevalence and incidence of infection among HCWs in Friuli Venezia Giulia region (north-eastern Italy) from March 1 to the end of the Italian lock-down, May 10, 2020. Methods. HCWs exposed to COVID-19 patients were actively surveyed and all HCWs were routinely tested with nasopharyngeal and oropharyngeal swab for RNA virus detection (n. 54,670).Results:Infected HCWs (n. 595) represented the 32.3% of all COVID-19 cases in the region under 65 years of age, and incidence of infection was 11.4 cases/1000 workers. HCWs accounted for a significant proportion of coronavirus infection and experienced high infection incidence after unprotected contact. Conclusions. HCWs’ knowledge of SARS-CoV-2 epidemiology and proper infection control practices are critical to the control of the disease. 相似文献
993.
Elena Savilo Ralph M. Meyer Praniti Soamboonsrup Linda Sunisloe George L. Frank Gerard T. Simon Peter B. Neame 《American journal of hematology》1995,50(3):209-214
A case of CD56/NCAM+ malignant lymphoma is reported. Only a rare malignant lymphoma cell showed azurophilic granules in the cytoplasm of Giesma-stained preparations, while electron microscopic examination revealed occasional cytoplasmic granules with paracrystalline inclusions. The most common phenotype seen in NK lymphomas, CD2+, CD3-, CD56+, CD16-, CD57-, was present in the case. Cases with this phenotype have been interpreted to represent either true NK lymphoma or T-cell lymphoma with NK expression. Genotyping, where performed, has shown TCR germline configuration. Our case showed TCRβ rearrangement indicating that the above phenotype can be associated with a peripheral T-cell lymphoma. 相似文献
994.
Balzhima Shagdarova Mariya Konovalova Yuliya Zhuikova Alexey Lunkov Vsevolod Zhuikov Dolgor Khaydapova Alla Ilina Elena Svirshchevskaya Valery Varlamov 《Materials》2022,15(1)
Diabetes mellitus continues to be one of the most common diseases often associated with diabetic ulcers. Chitosan is an attractive biopolymer for wound healing due to its biodegradability, biocompatibility, mucoadhesiveness, low toxicity, and hemostatic effect. A panel of hydrogels based on chitosan, collagen, and silver nanoparticels were produced to treat diabetic wounds. The antibacterial activity, cytotoxicity, swelling, rheological properties, and longitudinal sections of hydrogels were studied. The ability of the gels for wound healing was studied in CD1 mice with alloxan-induced diabetes. Application of the gels resulted in an increase in VEGF, TGF-b1, IL-1b, and TIMP1 gene expression and earlier wound closure in a comparison with control untreated wounds. All gels increased collagen deposition, hair follicle repair, and sebaceous glands formation. The results of these tests show that the obtained hydrogels have good mechanical properties and biological activity and have potential applications in the field of wound healing. However, clinical studies are required to compare the efficacy of the gels as animal models do not reproduce full diabetes pathology. 相似文献
995.
Obada T Alhalabi Michael N C Fletcher Thomas Hielscher Tobias Kessler Tolga Lokumcu Ulrich Baumgartner Elena Wittmann Silja Schlue Mona Gttmann Shaman Rahman Ling Hai Lea Hansen-Palmus Laura Puccio Ichiro Nakano Christel Herold-Mende Bryan W Day Wolfgang Wick Felix Sahm Emma Phillips Violaine Goidts 《Neuro-oncology》2022,24(1):39
BackgroundGlioblastoma is the most common primary malignancy of the central nervous system with a dismal prognosis. Genomic signatures classify isocitrate dehydrogenase 1 (IDH)-wildtype glioblastoma into three subtypes: proneural, mesenchymal, and classical. Dasatinib, an inhibitor of proto-oncogene kinase Src (SRC), is one of many therapeutics which, despite promising preclinical results, have failed to improve overall survival in glioblastoma patients in clinical trials. We examined whether glioblastoma subtypes differ in their response to dasatinib and could hence be evaluated for patient enrichment strategies in clinical trials.MethodsWe carried out in silico analyses on glioblastoma gene expression (TCGA) and single-cell RNA-Seq data. In addition, in vitro experiments using glioblastoma stem-like cells (GSCs) derived from primary patient tumors were performed, with complementary gene expression profiling and immunohistochemistry analysis of tumor samples.ResultsPatients with the mesenchymal subtype of glioblastoma showed higher SRC pathway activation based on gene expression profiling. Accordingly, mesenchymal GSCs were more sensitive to SRC inhibition by dasatinib compared to proneural and classical GSCs. Notably, SRC phosphorylation status did not predict response to dasatinib treatment. Furthermore, serpin peptidase inhibitor clade H member 1 (SERPINH1), a collagen-related heat-shock protein associated with cancer progression, was shown to correlate with dasatinib response and with the mesenchymal subtype.ConclusionThis work highlights further molecular-based patient selection strategies in clinical trials and suggests the mesenchymal subtype as well as SERPINH1 to be associated with response to dasatinib. Our findings indicate that stratification based on gene expression subtyping should be considered in future dasatinib trials. 相似文献
996.
997.
998.
Ildar Salakhov Elena Tkacheva Valeriy Kozlov Dmitriy Galanin Anas Sakhabutdinov 《RSC advances》2021,11(34):20916
The regularities of ethylene–propylene copolymerisation over a vanadium oxytrichloride (VOCl3)–ethylaluminium sesquichloride (EASC) catalytic system in the presence of hexachloro-p-xylene (HCPX), tert-butyl chloride, trichlorotoluene, hexachlorocyclopentadiene, and trichloroacetate were studied. The main kinetic regularities of ethylene–propylene copolymerisation when using HCPX were determined and the kinetic parameters of the process were obtained. It was shown that hexachloro-p-xylene is the most efficient promoter of polymerisation that increases activity of the “vanadium” catalyst severalfold and enhances propylene reactivity in its copolymerisation with ethylene. A number of molecular characteristics and physicochemical parameters were determined for the synthesised samples of ethylene–propylene copolymers. The resulting copolymers have a higher molecular weight and a broad molecular weight distribution and are richer in propylene monomers compared to the copolymers synthesised in the catalytic system without HCPX. Modification of the “vanadium” catalyst yields the copolymer with a more homogeneous structure. Assumptions were made about the mechanism of action of the promoter under study in the VOCl3–EASC catalytic system.Hexachloro-p-xylene was found to be an effective promoter of olefin copolymerisation in the presence of vanadium catalyst, which increases the activity severalfold, enhances propylene incorporation in the copolymer, and results in a more homogeneous polymer. 相似文献
999.
Pavel G. Shangin Irina V. Krylova Andrey V. Lalov Anna Y. Kozmenkova Evgeniya A. Saverina Petr A. Buikin Alexander A. Korlyukov Alyona A. Starikova Elena N. Nikolaevskaya Mikhail P. Egorov Mikhail A. Syroeshkin 《RSC advances》2021,11(35):21527
The concept of using redox-active ligands, which has become extremely widespread in organometallic chemistry, is often considered from ‘their effect on the metal center properties’ point of view and ‘how to modify the ligands’. In this paper, we present the reverse side of this effective approach – a dramatic change of redox properties of ligands under the influence of a redox-inert metal. Germanium derivatives based on 2,3-dihydroxynaphthalene (1) and N,N′-bidentate ligands, namely 2,2′-bipyridine (2) and 1,10-phenanthroline (3), were obtained and characterized by CV, UV-vis spectroscopy, DFT calculations and in the case of 3 X-ray diffraction. It was shown that the HOMO of the complexes is almost completely located on the naphthalene fragment while the LUMO is on the N,N-ligands. At the same time, there are no boundary molecular orbitals on the germanium atom, but it forms the axial part of the molecule holding two opposite motifs together. Moreover, it sharply affects the level of HOMO and LUMO. Derivatives 2 and 3 are more easily oxidized compared to 2,3-dihydroxynaphthalene by 0.31–0.34 V (7–8 kcal mol−1) and are more easily reduced compared to N,N-donors by 1.08–1.15 V (25–26.5 kcal mol−1). All this together makes it possible to form a system with a narrow HOMO/LUMO gap (∼2 eV). The crystal structure of 3 consists of alternating monomolecular easily oxidizing and easily reducing layers formed due to intermolecular interactions, in particular π-stacking. In addition, in contrast to 1 that starts to decompose noticeably at the temperatures from 200 °C, 2 and 3 have an extremely high thermal stability. They remain stable with no signs of decomposition and melting up to 400 °С. We believe that this approach to the formation of the supramolecular structure may present prospects for obtaining new functional materials.The concept of using redox-active ligands is often considered from ‘their effect on the metal center properties’ point of view. We present the reverse side of this approach – change of redox properties of ligands under the influence of metal. 相似文献
1000.
Elena Massa Clelia Donisi Nicole Liscia Clelia Madeddu Valentino Impera Stefano Mariani Mario Scartozzi Eleonora Lai 《Clin Pract Epidemiol Ment Health》2021,17(1):295
Background:Depression is a common psychiatric problem in the elderly and oncology patients. In elderly people with cancer, depression has a peculiar phenomenology. It has a significant impact on the quality of life. Moreover, it is associated with poor adherence to treatments, increased risk of suicide, and mortality. Nevertheless, the topic of depression in elderly people with cancer remains unexplored.Objective:The main goal of this article is to review the literature from the past 20 years on the relationships between depression, cancer, and aging.Methods:The methods followed the Prisma model for eligibility of studies. The articles in which the keywords “depression”, “cancer”, “ elderly, aging, or geriatric” were present, either in the text or in the abstract, were selected. 8.056 articles, by matching the keywords “depression and elderly and cancer,” were identified. Only 532 papers met the eligibility criteria of search limits and selection process. Out of 532 papers, 467 were considered irrelevant, leaving 65 relevant studies. Out of 65 suitable studies, 39 (60.0%) met our quality criteria and were included.Results:The risk factors associated with depression in elderly people with cancer can be divided into 4 groups: 1) tumor-related; 2) anticancer treatment-related; 3) patients-related; 4) number and type of comorbidity. The main obstacles in diagnosing depression in elderly patients with cancer are the overlap of the symptoms of cancer and side effects of treatment with the symptoms of depression but also the different ways of reporting depressive symptoms of elderly people and the different clinical types of depression. There is a lack of data regarding validated scales to assess depression in geriatric patients with cancer. Any mental illness, specifically co-occurring anxiety and depression, increases the risk of diagnosis delay and anticancer treatment adherence. Cancer and the diagnosis of mental disorders prior to cancer diagnosis correlate with an increased risk for suicide. A non-pharmacological therapeutic approach, pharmacological treatment and/or a combination of both can be used to treat elderly patients with cancer, but a detailed analysis of comorbidities and the assessment of polypharmacy is mandatory in order to avoid potential side-effects and interactions between antidepressants and the other drugs taken by the patients.Conclusion:Future research should be conducted with the aim of developing a modified and adapted assessment method for the diagnosis and treatment of depression in elderly people with cancer in order to improve their clinical outcomes and quality of life. 相似文献