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排序方式: 共有6439条查询结果,搜索用时 15 毫秒
61.
Beata Gawdis-Wojnarska Marek Brzosko Jacek Fliciński Krzysztof Marlicz Teresa Starzyńska Rodney J Scott Jan Lubiński 《Hereditary cancer in clinical practice》2004,2(2):65-68
Gastric cancer is the second most frequently diagnosed malignancy worldwide and therefore represents a significant healthcare burden. Environmental and genetic factors are involved in the development of gastric cancer. To date only one clear genetic predisposition has been identified involving mutations in the E-cadherin gene. The disease phenotype in patients harbouring E-cadherin mutations appears to be specifically related to diffuse gastric cancer. Little is known genetically about the other forms of gastric cancer. Since there is a growing awareness about the necessity of early intervention criteria have been developed that aid the identification of hereditary forms of gastric cancer. The aim of the current study was to identify minimal inclusion criteria so that nuclear pedigree families can be provided with risk assessment and/or genetic testing.The results reveal that inclusion features described herein such as (a) gastric cancer diagnosed before 46 years of age; (b) two gastric cancers among first degree relatives diagnosed over the age of 50 are useful in identifying suspected hereditary gastric cancer patients. 相似文献
62.
Tadeusz agoda Sabrina Vantadori Karolina Gowacka Marta Kurek Krzysztof Kluger 《Materials》2022,15(10)
The Smith-Watson-Topper parameter (SWT) in its original form was designed to estimate the fatigue life of metal materials in a uniaxial load state (tension–compression) in the range up to fatigue crack initiation, with non-zero mean values. This parameter is based on the analysis of both stress and strain. Therefore, the stress–strain criterion is the focus, rather than the energy criterion. This paper presents the original SWT model and its numerous modifications. The first part presents different versions of this parameter defined by the normal parameters. Then, it presents versions defined through the tangent parameter and the most promising parameter defined through the tangent and normal parameters. It was noted that the final form of the equivalent value is defined either by stress or by an energy parameter. Therefore, the possible characteristics from which the fatigue life can be determined are also presented. 相似文献
63.
Chen L Gao G Felczak K Bonnac L Patterson SE Wilson D Bennett EM Jayaram HN Hedstrom L Pankiewicz KW 《Journal of medicinal chemistry》2007,50(23):5743-5751
Novel tiazofurin adenine dinucleotide (TAD) analogues 25-33 containing a substituent at C2 of the adenine ring have been synthesized as inhibitors of the two isoforms of human IMP-dehydrogenase. The 2-ethyl TAD analogue 33 [Ki = 1 nM (type I), Ki = 14 nM (type II)] was found to be the most potent. It did not inhibit three other cellular dehydrogenases up to 50 microM. Mycophenolic adenine bis(phosphonate)s containing a 2-phenyl (37) or 2-ethyl group (38), were prepared as metabolically stable compounds, both nanomolar inhibitors. Compound 38 [Ki = 16 nM (type I), Ki = 38 nM (type II)] inhibited proliferation of leukemic K562 cells (IC50 = 1.1 microM) more potently than tiazofurin (IC50 = 12.4 microM) or mycophenolic acid (IC50 = 7.7 microM). 相似文献
64.
Lucie Stuchlíková Věra Králová Kateřina Lněničková Tomáš Zárybnický Petra Matoušková Veronika Hanušová Martin Ambrož Zdeněk Šubrt Lenka Skálová 《Drug testing and analysis》2018,10(7):1139-1146
Flubendazole (FLU), a benzimidazole anthelmintic drug widely used in veterinary medicine, has been approved for the treatment of gut‐residing nematodes in humans. In addition, FLU is now considered a promising anti‐cancer agent. Despite this, information about biotransformation of this compound in human is lacking. Moreover, there is no information regarding whether cancer cells are able to metabolize FLU in order to deactivate it. For these reasons, the present study was designed to identify all metabolites of Phase I and Phase II of FLU in human liver and in various cancer cells using ultra high‐performance liquid chromatography–tandem mass spectrometry (UHPLC–MS/MS) analysis. Precision‐cut human liver slices and 9 cell lines of different origin (breast, colon, oral cavity) were used as in vitro model systems. Our study showed that FLU with a reduced carbonyl group (FLUR) is the only FLU metabolite formed in the human liver. All human cancer cell lines were able to form FLUR. In addition, methylated FLUR was detected in breast cells MCF7 and intestinal SW480 cells. The accumulation of FLU and its reduction to FLUR markedly differed among cells. The extent of FLU reduction was in a good correlation with the detected expression level of carbonyl reductase 1. In most cases, FLU entered in a higher amount and was reduced to a lesser extent in proliferating (metastatic) cells than in differentiated (non‐cancerous, non‐metastatic) ones. These results support the promising potential of FLU in anti‐cancer therapy. 相似文献
65.
Joanna Krajewska Krzysztof Nowicki Krzysztof Durka Paulina H. Marek-Urban Patrycja Wiska Tomasz Stpniewski Krzysztof Wo
niak Agnieszka E. Laudy Sergiusz Luliski 《RSC advances》2022,12(36):23099
Two isomeric benzosiloxaborole derivatives 3a and 5a bearing fluorine and 4,4-dimethyl-2-oxazolin-2-yl substituents attached to the aromatic rings were obtained. Both compounds were prone to hydrolytic cleavage of the oxazoline ring after initial protonation or methylation of the nitrogen atom. The derivative 3c featuring N-methylammoniumalkyl ester functionality was successfully subjected to N-sulfonylation and N-acylation reactions to give respective derivatives which demonstrates its potential for modular synthesis of structurally extended benzosiloxaboroles. Compound 5c bearing N-ammoniumalkyl ester underwent conversion to a unique macrocyclic dimer due to siloxaborole ring opening. Furthermore, an unexpected 4-electron reduction of the oxazoline ring occurred during an attempted synthesis of 5a. The reaction gave rise to an unprecedented 7-membered heterocyclic system 4a comprising a relatively stable B–O–B–O–Si linkage and stabilized by an intramolecular N–B coordination. It could be cleaved to derivative 4c bearing BOH and SiMe2OH groups which acts as a pseudo-diol as demonstrated by formation of an adduct with Tavaborole. Apart from the multinuclear NMR spectroscopy characterization, crystal structures of the obtained products were determined in many cases by X-ray diffraction. Investigation of biological activity of the obtained compounds revealed that derivatives 3e and 3f with pendant N-methyl arylsulfonamide groups exhibit high activity against Gram-positive cocci such as methicillin-sensitive Staphylococcus aureus ATCC 6538P, methicillin-resistant S. aureus (MRSA) ATCC 43300 as well as the MRSA clinical strains, with MIC values in the range of 3.12–6.25 mg L−1. These two compounds also showed activity against Enterococcus faecalis ATCC 29212 and Enterococcus faecium ATCC 6057 (with MICs of 25–50 mg L−1). The results of the antimicrobial activity and cytotoxicity studies indicate that 3e and 3f can be considered as potential antibacterial agents, especially against S. aureus MRSA.Transformations of oxazoline–benzosiloxaborole conjugates gave rise to novel boracyclic systems as well as functionalized derivatives featuring antibacterial activity. 相似文献
66.
Thrombotic thrombocytopenic purpura (TTP) is characterized by microangiopathic hemolytic anemia and thrombocytopenia, accompanied by microvascular thrombosis that causes variable degrees of tissue ischemia and infarction. About 10-20% of TTP cases are associated with the pregnancy. Preterm delivery and intrauterine fetal death are frequent pregnancy complications of TTP. The following paper presents the case of a 32-year-old woman with TTP relapse at 10 weeks of her second pregnancy. Despite regular fresh frozen plasma transfusions, intrauterine fetal death occurred at 21 weeks of gestation. Current views on TTP management during pregnancy have been presented in the article as well. 相似文献
67.
Magnowski P Medrek K Magnowska M Stawicka M Kedzia H Górski B Lubiński J Spaczyński M 《Ginekologia polska》2008,79(8):544-549
OBJECTIVE: There is an increasing evidence that genetic factors play a role in the etiology of malignant tumors. Mutations of BRCA1 and BRCA2 genes are responsible for an increased risk of ovarian cancer. The role of mutations in NOD2 gene in this type of neoplasm is still under investigation. THE AIM: The aim of this study was to determine: 1. incidence of NOD 2 3020insC constitutional mutation in a group of consecutive women with ovarian cancer, 2. risk of developing ovarian cancer in patients with NOD2 gene mutation, 3. clinical and pathological features of ovarian cancer in NOD2 gene mutation carriers. PATIENTS AND METHODS: Clinical and pathological data were collected from 257 non-selected patients with primary epithelial ovarian cancer. The researches identified NOD2 3020insC gene mutation. On the basis of patient source documentation we obtained the data concerning the age of patients at diagnosis, histopathological recognition, FIGO stage and morphological grade G. RESULTS: 19 out of 257 women were identified with germ-line 3020insC mutation of NOD2 gene (7.39%). An increased risk of ovarian cancer in NOD2 mutation carriers was not revealed (OR=1.01; p=0.928; 95% Cl=0.61-1.66). The mean age at diagnosis of patients with NOD2 mutation was 54.8 (SD=9.9), while for non-carriers it was 53.2 (SD=10.2). The difference between these frequencies was statistically irrelevant (p=0.550). Clinical and pathological profile of ovarian cancer was made. We assessed the following features: age at disease onset, histopathology, FIGO stage and morphological grade G. For NOD2 mutation carriers no statistically significant features of ovarian cancer were revealed. CONCLUSION: 1. Despite high frequency of constitutional mutations occurrence in NOD2 gene in women with ovarian cancer, genetic testing seem not to be justified in all women diagnosed with this disease. 2. Due to a lack of increased risk of ovarian cancer in NOD2 gene mutation carriers, proceedings for them may not differ from recommendations for general population. 3. It is difficult to determine characteristic clinical and pathological features of ovarian cancer for NOD2 gene mutation carriers. 相似文献
68.
Mrochem J Sodowski K Deja R Walaszek-Gruszka A Wojcieszek A Kołosza Z Chmura A Czernik E Masłyk B Bartnik W Cnota W 《Ginekologia polska》2008,79(4):271-275
OBJECTIVE: an attempt to determine the value of the simultaneous quantization of osteopontin (OPN), insulin-growth factor II (IGF II), leptin, prolactin and CA 125 for early detection of ovarian cancer. MATERIALS AND METHODS: Prospective study of 69 women including: 15 females with ovarian cancer; 33 females with benign ovarian neoplasm; 21 disease-free females; The levels of IGF II, prolactin, leptin and CA 125 were determined in serum, while the level of OPN was checked in plasma. RESULTS: The concentrations of IGF II, leptin and prolactin do not let us distinguish among disease-free females, females with ovarian cancer and those with benign ovarian neoplasms on the basis of biochemical markers. The comparison of OPN and CA 125 levels showed significant differences in the concentrations of the biomarkers between disease-free females and females with ovarian cancer, as well as between females with benign ovarian neoplasms and females with ovarian cancer. The ROC curves for two groups: disease-free females and females with ovarian cancer, proved the diagnostic value of OPN and CA 125. CONCLUSIONS: The simultaneous quantization of OPN, IGF II leptin and prolactin has not been proved useful for the early detection of ovarian cancer. Statistically significant increase of OPN & CA 125 levels was noted in case of women with ovarian cancer diagnosed through microscopic examination. The analysis of ROC curves showed comparable diagnostic usefulness of both markers. Quantization of OPN may have an additional value for treatment monitoring of women diagnosed with ovarian cancer but with concentration of CA 125 within the reference value. 相似文献
69.
OBJECTIVES: The demand for genetic amniocentesis in case of young pregnant women has significantly increased due to various new indications. Moreover, nowadays a growing number of women aged > or =35, who required genetic amniocentesis, get pregnant The aim of the following study has been to compare the course of the pregnancy, the delivery and the condition of the newborn in two groups of patients: 18-34 years old and > or =35 years old. MATERIAL AND METHODS: 783 women underwent the procedure of amniocentesis at the Department of Obstetrics of Medical University of Gdansk in 1996-2003. A group of 540 women, who answered the questionnaire about the course of the pregnancy and the delivery after the procedure, has been isolated. RESULTS: Fetal loss occurred in 2 cases (1.6%) in the group of the younger women and in 8 cases (0.8%) in the group of > or =35 year-olds (p=0.84). There was no statistically significant difference between younger and older patients when comparing complications after the procedure in the first three weeks following amniocentesis: spotting, bleeding, leakage of amniotic fluid. Frequency of late complications such as gestational diabetes mellitus, pregnancy induced hypertension and urinary tract infections were comparable in both age groups women. Cesarean section has been more frequently performed in case of the older women than in the group of younger patients, with statistical difference p=0.003. In most cases (33.9%) it has been an elective cesarean section, performed due to advanced maternal age rather than any obstetric cause. Frequency of pneumonia and the number of respiratory infections in the newborns have been comparable in both groups. CONCLUSIONS: Prenatal invasive diagnosis has no influence on frequency of complications during pregnancy and delivery in the group of women less than 35 years old and more than 35 years old. 相似文献
70.
DNA adducts, one of genetic damages markers, precede and finally can lead to oncogenic mutations. They appear in genome as a result of DNA bases damages caused by various and numerous environmental factors eg. ultraviolet light, ionic radiation, toxins and also endogenic substances, for example estrogens. It is believed that the creation of DNA adducts is a necessary but insufficient process for the neoplastic transformation of the cell. The following review presents concise knowledge about the DNA adducts creation and their sequels served in healthy and cancerous tissues of the female genital organs, on the base of the available data. 相似文献