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51.
Cytotechnology - Six extracts were obtained from plant species Hypericum perforatum L., collected at Samsun in Turkey. The aim of this study was to examine the mechanisms of the anticancer activity...  相似文献   
52.
Enediyne–peptide conjugates were designed with the aim to inhibit aminopeptidase N, a widespread ectoenzyme with a variety of functions, like protein digestion, inactivation of cytokines in the immune system and endogenous opioid peptides in the central nervous system. Enediyne moiety was embedded within the 12-membered ring with hydrophobic amino acid alanine, valine, leucine or phenylalanine used as carriers. Aromatic part of the enediyne bridging unit and the amino acid side chains were considered as pharmacophores for the binding to the aminopeptidase N (APN) active site. Additionally, the fused enediyne–amino acid “heads” were bound through a flexible linker to the l-lysine, an amino group donor. The synthesis included building the aromatic enediyne core at the C-terminal of amino acids and subsequent intramolecular N-alkylation. APN inhibition test revealed that the alanine-based derivative 9a inhibits the APN with IC50 of 34 ± 11 μM. Enediyne–alanine conjugate 12 missing the flexible linker was much less effective in the APN inhibition. These results show that enediyne-fused amino acids have potential as new pharmacophores in the design of APN inhibitors.  相似文献   
53.
The crystal and molecular structure of one imidazo[1,2-a]-s-triazine nucleoside and its antiviral activity are described. The crystal structure of 2-amino-8-(β-d-ribofuranosyl)imidazo-[1,2-a]-s-triazin-4-one monohydrate (C10H13N5O5·H2O) was solved by X-ray counter data. The compound crystallizes in the monoclinic space group P21 with cell dimensions a = 7.353 (1), b = 6.465 (1), c = 13.701 (1) Å, β = 104.64 (1)°. The structure was solved by direct methods and refined by full matrix least-squares technique to a final value of the conventional R-factor of 0.049 using 1998 observed intensities. The orientation of the base relative to the sugar ring defined in terms of rotation about the C(1′)-N(8) glycosyl bond is anti (47.8°). The ribose moiety exhibits C(2′)-endo, 2E conformation. The conformation around C(4′)-C(5′) is gauche?. Molecular packing is dominated by hydrogen bonds. Base stacking occurs long the b axis. 5-Aza-7-deazaguanosine has shown a marked antiviral activity in vitro against herpes simplex virus despite the fact that N(3) is effective as the hydrogen acceptor only.  相似文献   
54.
The antimicrobial and cytotoxic activities of isolates (CHCl3 and MeOH extracts and selected metabolites) obtained from the underground parts of the Balkan endemic plant Ferula heuffelii Griseb . ex Heuff . were assessed. The CHCl3 and MeOH extracts exhibited moderate antimicrobial activity, being more pronounced against Gram‐positive than Gram‐negative bacteria, especially against Staphylococcus aureus (MIC=12.5 μg/ml for both extracts) and Micrococcus luteus (MIC=50 and 12.5 μg/ml, resp.). Among the tested metabolites, (6E)‐1‐(2,4‐dihydroxyphenyl)‐3,7,11‐trimethyl‐3‐vinyldodeca‐6,10‐dien‐1‐one ( 2 ) and (2S*,3R*)‐2‐[(3E)‐4,8‐dimethylnona‐3,7‐dien‐1‐yl]‐2,3‐dihydro‐7‐hydroxy‐2,3‐dimethylfuro[3,2‐c]coumarin ( 4 ) demonstrated the best antimicrobial activity. Compounds 2 and 4 both strongly inhibited the growth of M. luteus (MIC=11.2 and 5.2 μM , resp.) and Staphylococcus epidermidis (MIC=22.5 and 10.5 μM , resp.) and compound 2 additionally also the growth of Bacillus subtilis (MIC=11.2 μM ). The cytotoxic activity of the isolates was tested against three human cancer cell lines, viz., cervical adenocarcinoma (HeLa), chronic myelogenous leukemia (K562), and breast cancer (MCF‐7) cells. The CHCl3 extract exhibited strong cytotoxic activity against all cell lines (IC50<11.0 μg/ml). All compounds strongly inhibited the growth of the K562 and HeLa cell lines. Compound 4 exhibited also a strong activity against the MCF‐7 cell line, comparable to that of cisplatin (IC50=22.32±1.32 vs. 18.67±0.75μM ).  相似文献   
55.
We investigated the effects of high pressure treatment on green plant leaves of two species, red rose (Rosa rubiginosa L.) and silver birch male (Betula pendula Roth). Both species were treated with pressure up to 100 bar in order to explore stress reactions, including desirable or undesirable metabolites in plant. When increasing the pressure, chlorophyll (Chl) fluorescence maximum shifts to the wavelength of about 680 nm for both red rose and silver birch, with shift rates–0.062 nm/bar and–0.082 nm/bar, respectively. High pressure induces the changes of the position for the second fluorescence maximum at approximately 730 nm in both species with the same shift rate–0.083 nm/bar. When increasing pressure the change of the photosynthetic apparatus efficiency decreases for both plant species slowly and nonlinearly. High-pressure treatments irreversibly damaged the leaf tissue and at this way induced changes of Chl fluorescence and photosynthetic efficiency.  相似文献   
56.
The purpose of the paper was to ascertain the factors which affect the satisfaction of patients with the prosthetic therapy. The purpose of the paper was also to ascertain if there are common factors characteristic for patients dissatisfied with the prosthetic therapy although the specialist appraises it as objectively successful. 52 patients of the Clinical Institute for Rehabilitation and Orthopedic Devices were participating in the research, to which, after unsuccessful surgical-prosthetic rehabilitation, reamputation and prosthetic provision was carried out, which was appraised successful by the doctor. It was endeavored to appraise to what extent the appraisal by the doctor corresponds to patient's satisfaction. On the basis of the questionnaire elaborated specifically for this research and the statistical processing, it was concluded that where the doctor appraised the prosthetic therapy as successful, the same opinion was shared by the majority of the patients (92.3%). Patients are similarly satisfied with the function and the esthetic quality of the prosthesis (73%). The reason why 7.7% of patients are dissatisfied in cases when the doctor considers that there are no objective reasons for that should be sought in non-medical factors. The age, the education, the marital status, the income state, the size of the residence and the regional affiliation do not have a significant influence on the satisfaction of patients with the prosthesis (p > 0.05). Patients with a minor handicap achieve satisfaction with the prosthetic therapy faster, as well as the right-handed persons if the prosthesis on the right-hand extremity is in question (p < 0.05). This investigation showed that the responsibility of not wearing prosthetic aids, both orthopedic, and dental prostheses, couldn't be only neuroticism by prosthetic patients, because that connection is not statistically significant (p < 0.09).  相似文献   
57.
In the period between the December 2000 and September 2004, altogether 13 patients underwent preoperative portal vein embolization (PPVE); 9 patients with colorectal metastases and 4 patients with hepatocellular carcinoma. The indirect splenic portography was performed after catheter was introduced into superior mesenteric artery via femoral artery approach. The portal vein was punctured percutaneously transhepatic under fluoroscopy. Following portography, selected portal vein segments were embolized by injecting polyvinil alcohol (PVA) particles until stasis of blood flow was achieved. Proximal parts of branches and the channel in the liver parenchyma were occluded with Gelfoam particles. The increase of the remnant liver parenchyma was measured by magnetic resonance imaging. iTwo patients experienced post-embolization syndrome and another one had subcapsular hematoma. The volume of the liver parenchyma increased minimally for 8% and maximally for 109%. Altogether, 10 patients underwent surgical resection. In two patients, the disease progressed and carcinoma spread to the previously healthy liver lobe and in one there was no hypertrophy and we decided for artery chemoembolization (AC). The results show that PPVE triggers a strong regenerative response resulting in hypertrophy of normal liver parenchyma and expand possibilities of curative surgery for patients who would not otherwise have been candidates for extended resection.  相似文献   
58.
In this study we investigated the association of the interleukin-1 receptor antagonist gene variable number tandem repeat (IL1RN VNTR) polymorphism and of the inhibitor of kappa B-like protein (IKBL) gene polymorphism with myocardial infarction (MI) in a group of patients with type 2 diabetes. The IL1RN VNTR and the IKBL+ 738T > C gene polymorphisms were tested in 374 Caucasians: 151 cases with MI and 223 subjects with no history of coronary artery disease. The IL1RN VNTR polymorphism was not a risk factor for MI in Caucasians with type 2 diabetes (genotype 22 vs. the rest: odds ratio (OR) 1.6; 95% confidence interval (CI) = 0.8-3.5; p = 0.2). We also failed to demonstrate that IKBL+ 738T > C gene polymorphism was associated with MI in patients with type 2 diabetes (OR = 0.9; 95% CI = 0.3-2.6; p = 0.9). We provide evidence that the IL1RN VNTR and the IKBL + 738T > C gene polymorphisms are not risk factors for MI in Caucasians with type 2 diabetes.  相似文献   
59.
The aim of this study was to investigate the prevalence of pelvic organ prolapse in urban and rural women and to identify possible related factors. They were 1749 participants; one thousand four hundred seventeen (81%) urban women and 332 rural residents (19%). The urban and rural women were congruently regarding to age, parity, using oral contraceptives and postmenopausal status. The urban women were more often obese (p < 0.01), estrogen replacement users (p < 0.001), smokers (p < 0.001), with mild (p < 0.001) and high (p < 0.001) education, and they were often divorced (p < 0.05) than rural women. Rural women were more often alcohol consumers (p < 0.001), with low level of education (p < 0.001) and more often married (p < 0.05) than rural examinees. There were no association between the presence of prolapse and: weight, menopausal status, oral contraceptives and estrogen replacement using, smoking, alcohol consuming and marital status. There were not observed differences in prevalence of prior hysterectomy, urinary incontinence, uroinfectio, sexual and bowel dysfunction between both groups. The prevalence of cystocele, rectocele and uterine prolapse were similar among urban and rural participants. In conclusion, a more complete picture of factors associated with genital prolapse would include in investigation, such as molecular and genetic ones.  相似文献   
60.
Previous findings on structural rearrangements in the chloroplast genome of Cuscuta (dodder), the only parasitic genus in the morning-glory family, Convolvulaceae, were attributed to its parasitic life style, but without proper comparison to related nonparasitic members of the family. Before molecular evolutionary questions regarding genome evolution can be answered, the phylogenetic problems within the family need to be resolved. However, the phylogenetic position of parasitic angiosperms and their precise relationship to nonparasitic relatives are difficult to infer. Problems are encountered with both morphological and molecular evidence. Molecular data have been used in numerous studies to elucidate relationships of parasitic taxa, despite accelerated rates of sequence evolution. To address the question of the position of the genus Cuscuta within Convolvulaceae, we generated a new molecular data set consisting of mitochondrial (atpA) and nuclear (RPB2) genes, and analyzed these data together with an existing chloroplast data matrix (rbcL, atpB, trnL-F, and psbE-J), to which an additional chloroplast gene (rpl2) was added. This data set was analyzed with an array of phylogenetic methods, including Bayesian analysis, maximum likelihood, and maximum parsimony. Further exploration of data was done by using methods of phylogeny hypothesis testing. At least two nonparasitic lineages are shown to diverge within the Convolvulaceae before Cuscuta. However, the exact sister group of Cuscuta could not be ascertained, even though many alternatives were rejected with confidence. Caution is therefore warranted when interpreting the causes of molecular evolution in Cuscuta. Detailed comparisons with nonparasitic Convolvulaceae are necessary before firm conclusions can be reached regarding the effects of the parasitic mode of life on patterns of molecular evolution in Cuscuta.  相似文献   
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