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排序方式: 共有494条查询结果,搜索用时 31 毫秒
31.
de Oliveira JH Grube A Köck M Berlinck RG Macedo ML Ferreira AG Hajdu E 《Journal of natural products》2004,67(10):1685-1689
The chemical investigation of the cytotoxic and antituberculosis active MeOH crude extract of the marine sponge Pachychalina sp. led to the isolation of six new nitrogenous metabolites, including ingenamine G (1), as well as a mixture of new cyclostellettamines G, H, I, K, and L (10-14) with the known cyclostellettamines A-F (4-9). Structural assignments of compound 1 were based on the analysis of MS and NMR data, while the structures of compounds 10-14 could be established by HPLC-MS/MS analysis. Ingenamine G displayed cytotoxic activity against HCT-8 (colon), B16 (leukemia), and MCF-7 (breast) cancer cell lines, antibacterial activity against Staphylococcus aureus (ATCC 25923), Escherichia coli (ATCC 25922), and four oxacilin-resistant S. aureus strains, and antimycobacterial activity against Mycobacterium tuberculosis H37Rv. 相似文献
32.
Akyol D Hajdu C Ferber A O'reilly-Green C Giancotti FR Dorsett BH Opher E Divon MY 《American journal of obstetrics and gynecology》2003,189(1):155-158
OBJECTIVE: The purpose of this study was to evaluate the correlation between placental and umbilical cord nucleated red blood cell counts. STUDY DESIGN: Eighty placentas and their matched umbilical cord blood samples were collected prospectively immediately after delivery. In vitro fine-needle aspiration biopsy specimens were used to obtain placental tissue samples. Nucleated red blood cells were counted by both manual microscopy and flow cytometry. Statistical analysis included Wilcoxon signed rank test and Spearman correlation. RESULTS: The median nucleated red blood cell counts/100 white blood cell counts for manual microscopy in umbilical cord blood; placental samples were 7.5 and 3.0, respectively (P <.0001). The median nucleated red blood cell counts for flow cytometric determination in umbilical cord blood and placental samples were 11.3 and 8.6, respectively (P <.0001). The Spearman correlation between manually counted umbilical cord blood samples and the placental tissue specimens was 0.66 (P <.0001). The Spearman correlation between flow cytometrically counted umbilical cord blood nucleated red blood cell and nucleated red blood cell counts that were obtained from the placenta was statistically significant (r = 0.74, P <.0001). The Spearman correlation between manual microscopy and flow cytometry for umbilical cord samples and their matched placental tissue specimens were 0.80 and 0.58, respectively, with all probability values at <.0001. CONCLUSION: Previous studies have reported an association between acute and chronic hypoxia and elevated nucleated red blood cells. Our results indicate that in vitro placental nucleated red blood cell counts correlate with umbilical cord nucleated red blood cell counts and suggest that antenatal evaluation of fetal nucleated red blood cells could be achieved by placental fine-needle aspiration biopsy. 相似文献
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A case of prenatally diagnosed Yq deletion is described. Fluorescence in situ hybridisation (FISH) was used to identify the abnormal chromosome and to exclude mosaicism. Based on the cytogenetic result and the ultrasound investigation the pregnancy was continued. A newborn with normal male genitalia was delivered. Microdeletion analysis of the Yq showed the absence of the AZFc region. This type of deletion has been described as being associated with azoospermia or oligozoospermia with a progressive decrease of sperm number over time. Long-term andrological follow-up of the newborn will be necessary with eventual cryoconservation of sperm at early adulthood. The present report proposes that AZF analysis combined with FISH has an important role in accurate genetic counselling in sex chromosome anomalies. 相似文献
36.
Benign soft tissue tumors: classification and natural history 总被引:1,自引:0,他引:1
S I Hajdu 《CA: a cancer journal for clinicians》1987,37(2):66-76
37.
B Zheng K Oishi M Shoji H Eibl W E Berdel J Hajdu W R Vogler J F Kuo 《Cancer research》1990,50(10):3025-3031
The effects and modes of action of certain antineoplastic phospholipid analogues (racemic 1-O-octadecyl-2-O-methyl glycero-3-phosphocholine, BM 41.440, JH-1, CV-3988, and HePC) on (sodium plus potassium)-activated adenosine triphosphatase (Na,K-ATPase) and sodium pump activities were investigated. Inhibition of Na,K-ATPase in purified rat brain synaptosomal membranes by these lipids, in contrast to ouabain, was subject to membrane surface dilution and unaffected by whether the reaction was started with KCl, NaCl, or ATP. Kinetic analysis indicated that the analogues, again dissimilar to ouabain, were likely to interact directly or indirectly with sodium-binding sites of Na,K-ATPase located at the intracellular surface of the plasma membrane, a conclusion also supported by studies using the inside-out vesicles of human erythrocyte membranes. The studies also showed that ouabain (but not the lipids) increased the affinity constant of Na,K-ATPase for K+, whereas the lipids (but not ouabain) increased that for Na+. The lipids also inhibited 86Rb uptake by intact human leukemia HL60 cells at potencies quite comparable to those seen for inhibition of purified protein kinase C or Na,K-ATPase. It is suggested that Na,K-ATPase (sodium pump) might represent a hitherto unrecognized site of action for the lipid analogues, and that the antineoplastic effects of the agents might be due to, in part, inhibition of both protein kinase C and Na,K-ATPase and perhaps other membrane-associated enzymes. 相似文献
38.
Recurrence-free survival time for surgically treated soft tissue sarcoma patients. Multivariate analysis of five prognostic factors 总被引:7,自引:0,他引:7
H W Heise M H Myers W O Russell H D Suit F M Enzinger J H Edmonson J Cohen R G Martin W T Miller S I Hajdu 《Cancer》1986,57(1):172-177
A staging system, based upon the experience of 1215 patients, was published by the American Joint Committee Task Force on Soft Tissue Sarcoma in 1977. A subset of these patients, 594, was selected to study recurrence-free survival time. The authors found 331 patients with a recurrence within 5 years (100 local only, 123 metastatic only, and 108 local + metastatic); median months to recurrence was 9.7. Within 5 years, recurrence was clearly associated with mortality: among the 331 patients who experienced a recurrence, 245 died, whereas only 31 died among the 263 who had no recurrence. To further evaluate the utility of the published staging system, a multivariate analysis of five factors was carried out for 297 of the 594 patients (patients with unknown information for any one of these factors were excluded). Factors in addition to grade that exerted a significant influence on recurrence were: direct extension, symptoms, and location of tumor when survival was measured to the first of any recurrence, and tumor size, measuring survival to the first metastatic recurrence. It is therefore recommended that these factors be taken into account in staging this disease. Estimates of probable recurrence-free survival time based upon the multivariate model (Weibull) are also presented. 相似文献
39.
Forrest M Sun SY Hajdu R Bergstrom J Card D Doherty G Hale J Keohane C Meyers C Milligan J Mills S Nomura N Rosen H Rosenbach M Shei GJ Singer II Tian M West S White V Xie J Proia RL Mandala S 《The Journal of pharmacology and experimental therapeutics》2004,309(2):758-768
Sphingosine 1-phosphate (S1P) is a bioactive lysolipid with pleiotropic functions mediated through a family of G protein-coupled receptors, S1P(1,2,3,4,5). Physiological effects of S1P receptor agonists include regulation of cardiovascular function and immunosuppression via redistribution of lymphocytes from blood to secondary lymphoid organs. The phosphorylated metabolite of the immunosuppressant agent FTY720 (2-amino-2-(2-[4-octylphenyl]ethyl)-1,3-propanediol) and other phosphonate analogs with differential receptor selectivity were investigated. No significant species differences in compound potency or rank order of activity on receptors cloned from human, murine, and rat sources were observed. All synthetic analogs were high-affinity agonists on S1P(1), with IC(50) values for ligand binding between 0.3 and 14 nM. The correlation between S1P(1) receptor activation and the ED(50) for lymphocyte reduction was highly significant (p < 0.001) and lower for the other receptors. In contrast to S1P(1)-mediated effects on lymphocyte recirculation, three lines of evidence link S1P(3) receptor activity with acute toxicity and cardiovascular regulation: compound potency on S1P(3) correlated with toxicity and bradycardia; the shift in potency of phosphorylated-FTY720 for inducing lymphopenia versus bradycardia and hypertension was consistent with affinity for S1P(1) relative to S1P(3); and toxicity, bradycardia, and hypertension were absent in S1P(3)(-/-) mice. Blood pressure effects of agonists in anesthetized rats were complex, whereas hypertension was the predominant effect in conscious rats and mice. Immunolocalization of S1P(3) in rodent heart revealed abundant expression on myocytes and perivascular smooth muscle cells consistent with regulation of bradycardia and hypertension, whereas S1P(1) expression was restricted to the vascular endothelium. 相似文献
40.
Stefan Hajdu Andrea Lassnigg Wolfgang Graninger Alexander M. Hirschl Elisabeth Presterl 《Journal of orthopaedic research》2009,27(10):1361-1365
Infection of medical implanted material is associated with considerable morbidity and costs. In the following work, we investigated the effects of vancomycin, daptomycin, fosfomycin, tigecycline, and ceftriaxone on biofilms formed by Staphylococcus epidermidis isolates causative for implant infection and catheter‐associated bacteremia. Biofilms were studied using the static microtiter plate model and incubated with the antibiotics increasing the concentration from 1× to 128× the minimal inhibitory concentration (MIC) of the respective isolate tested. To quantify the reduction of the biomass, the optical density ratio (ODr) of stained biofilms and the number of growing bacteria were determined. Incubation of the staphylococcal biofilms with the antibiotics decreased the biofilm ODr (at baseline = 1) for ceftriaxone (0.83 ± 0.48) but minimally only for fosfomycin (0.96 ± 0.64), daptomycin (1.05 ± 0.59), tigecycline (1.18 ± 0.66), and vancomycin (0.98 ± 0.44) at exceedingly high concentrations of 128 × MIC. The significant reduction of the bacterial growth was not achieved for all antibiotics, not even at the highest concentrations tested. Using higher doses of the antibiotics may be of some value in the treatment of biofilm‐associated infections, although effects are seen only at clinically unachievable doses. However, to eradicate the staphylococcal biofilm, additional measures like debridement and/or removal of the implant are needed. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27:1361–1365, 2009 相似文献