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排序方式: 共有917条查询结果,搜索用时 15 毫秒
1.
Peter F. Bruning Jaap Van Doorn Johannes M. G. Bonfrr Paul A. M. Van Noord Catharina M. Korse Theodora C. Linders Augustinus A. M. Hart 《International journal of cancer. Journal international du cancer》1995,62(3):266-270
Insulin-like growth factor 1 (IGF-1) is a potent mitogen for human breast-cancer cells in vitro. In circulation, most of IGF-1 is bound to IGF-binding protein 3 (IGFBP-3). This high-affinity binding is thought to have an important limiting effect on the availability of IGF-1 for biological activity. To assess the availability of IGF-1 for receptor binding, we determined serum levels of IGF-1 and IGFBP-3 and IGF-1/IGFBP-3 ratios. In a case-control study, 150 women aged 38 to 75 years presenting with stage-l or-II breast cancer were investigated just prior to surgery (n = 76), or to irradiation one month after surgery (n = 74). The population-based control group consisted of 441 women of the same age having no breast cancer. Women reporting diabetes mellitus or other hormonal abnormalities were excluded. Premenopausal cases showed elevated IGF-1 serum concentrations, decreased IGFBP-3 levels and increased IGF-1/IGFBP-3 ratios. The IGF-1/IGFBP-3 ratio was a significant breast-cancer risk factor, also after adjustment for age, family history, height, body-mass index, body-fat distribution, and serum levels of C-peptide. The relative risk was 7.34 for the highest compared with the lowest quintile of IGF-1/IGFBP-3. The presence or absence of tumor had no influence on these results. Increased levels of available IGF-1 in the circulation of pre-menopausal women may contribute to the development of breast cancer. © 1995 Wiley-Liss Inc. 相似文献
2.
Alexandros GERAKIS Angeliki BARBATSI Sophia SARANTI Theodora STROGYLOU Dimitrios VALIS 《Nephrology (Carlton, Vic.)》1998,4(5-6):403-406
SUMMARY: We studied the effect of haemodialysis on the serum levels of tumour markers in 78 patients, 49 men and 29 women with a mean age of 61 ± 2 years, who had been undergoing haemodialysis for 39 ± 10 months. No patient had any clinical evidence of malignancy. Serum values of carcinoembryonic antigen (CEA), alpha-fetoprotein (AFP), squamous-cell-carcinoma-related antigen (SCC), neuron-specific enolase (NSE), tissue polypeptide antigen (TPA), CA 15-3, CA 19–9, and among males prostate-specific antigen (PSA) were determined before and after dialysis. Postdialysis values, after being corrected for haemoconcentration, were compared with predialysis values. A significant increase of 32% was observed in NSE levels ( P <0.001) and of 21% in CA 15-3 ( P <0.001) after haemodialysis. A lesser, but still statistically significant, increase (8-12%) was observed in SCC, AFP and CEA levels ( P <0.05), while the values of the remaining three markers remained unchanged. In conclusion, an increase in some tumour markers was found in our patients after dialysis, a finding which requires further investigation. 相似文献
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Sainova IV Kril AI Simeonov KB Popova TP Ivanov IG 《Journal of virological methods》2005,124(1-2):37-40
The ability for replication of vaccine avian pox viral strains FK and Dessau in cell clones, derived from the EBTr cell line, derived from embryonic bovine trachea, was studied. The derived seven cell clones showed different morphological characteristics and diverse sensitivity to both vaccine avian pox viral strains. Hence, the EBTr-derived cell clones could be used for cultivation, as well as for differentiation of vaccine avian pox viral strains. In addition, studies have been undertaken to elucidate the possible use of cultivated strains in these heterologous cell culture system's vaccine avian pox viral strains for biotechnology, as well as for solving problems, related to infection of people with avian viruses. 相似文献
5.
Alexandros Drivalos Georgios Emmanouil Maria Gavriatopoulou Evangelos Terpos Theodoros N. Sergentanis Theodora Psaltopoulou 《Urologic oncology》2021,39(4):221-232
Background: The prompt identification of patients with poor prognosis is essential in order to improve the treatment outcomes in prostate cancer (CaP); as a novel approach, several molecular markers, including integrins, have been discussed as prognostic biomarkers. Our aim was to comprehensively examine aberrant expression of integrins in correlation with clinicopathological features and prognosis in CaP by synthesizing all available evidence, in a systematic review and meta-analysis. Methods: A systematic review and meta-analysis was performed in accordance with the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) guidelines. Scientific literature databases (Pubmed, Embase, and Scopus) were systematically searched until May 10, 2020. Random-effects (DerSimonian-Laird) models were used to estimate pooled odds ratios (ORs) for cross-sectional correlations with clinicopathological characteristics and relative risks for longitudinal associations with prognosis. Results: Fourteen studies were included with a total number of 3,194 CaP cases examined (13 cross-sectional and four longitudinal cohort study arms). Correlation of low expression of α6 (pooled OR = 0.10, 95% confidence interval [CI]: 0.04–0.28, P < 0.001) and β1 (pooled OR = 0.45; 95% CI: 0.21–1.00, P = 0.049) integrin with high Gleason score was noted. A borderline trend between reduced expression of α6 integrin and an advanced clinical stage of CaP (pooled OR = 0.48; 95% CI: 0.22-1.03, P = 0.06) was observed. No associations with biochemical recurrence and survival were documented. Conclusions: Evidence on the association of low expression of integrins α6 and β1 and more advanced CaP exist, whereas significant results on survival were not documented; further studies are warranted. 相似文献
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Chris J. Callaghan Benedict L. Phillips Theodora Foukaneli Susan Robinson Christopher J. E. Watson 《American journal of transplantation》2021,21(4):1376-1381
Ex situ normothermic machine perfusion (NMP) is being used increasingly in the assessment of higher risk deceased donor organs and to facilitate prolonged organ storage. Third-party packed red blood cells (pRBCs) are often used as an oxygen carrier in the perfusate of ex situ NMP. Despite the increasing interest in NMP, comparatively little attention has been paid to the appropriate selection of pRBCs. This includes the choice of ABO blood group and Rhesus D status, the need for special requirements for selected recipients, and the necessity for traceability of blood components. Flushing organs with cold preservation solution after NMP removes the overwhelming majority of third-party allogeneic pRBCs, but residual pRBCs within the organ may have biologically relevant effects following implantation as they enter the recipient's circulation. This review considers these issues, and suggests that national transplant and blood transfusion agencies work together to develop a co-ordinated approach within each country. This is especially important given the possibility of organ re-allocation between centers after ex situ NMP, and the ongoing development of organ perfusion hubs. 相似文献
8.
Andreas Katsanos Georgios Labiris Michael Fanariotis Theodora Tsirouki Dimitrios Chatzoulis 《Acta ophthalmologica. Supplement》2008,86(8):871-876
Purpose: To examine the association between measures of neuroretinal matrix integrity as determined with Rarebit perimetry and optical coherence tomography (OCT)‐derived retinal nerve fibre layer thickness. Methods: One randomly selected eye of 30 White primary open‐angle glaucoma patients (age: 60.9 ± 11.7 years; MD: ?3.2 ± 5.1 dB) and 16 healthy White individuals (age: 33.2 ± 6.4 years; MD: ?0.8 ± 0.8 dB) were included in the study. Participants underwent Rarebit perimetry testing (central field, software version 4) and an OCT fast retinal nerve fibre layer (RNFL) scan. Correlation was investigated between hemifield Rarebit scores and the corresponding RNFL values, as well as between global Rarebit scores and the respective RNFL measures. Results: Statistically significant correlations of average hit rate (HR) < 90 and mean hit rate (MHR) were detected with Max–Min and average thickness (Pearson’s r ranging from 0.393 to 0.474). Number HR < 90 showed a moderate correlation only with Max–Min (r = ?0.396, P = 0.030). Regarding the association between hemifield hit rates and the corresponding OCT thickness parameters, only inferior maximum correlated moderately with HR superior (r = 0.385, P = 0.035). A tendency was detected for the relationship of superior maximum with HR inferior (r = 0.345, P = 0.062). For the control group, no significant correlation was found for any of the global or hemifield indices and the corresponding thickness values. Conclusion: Although Rarebit perimetry is based on a physiological principle distinctly different from conventional perimetry, it provides global indicators of neuroretinal matrix integrity that correlate with some OCT‐derived RNFL thickness measures. 相似文献
9.
Emergency obstetric hysterectomy 总被引:4,自引:0,他引:4
Daskalakis G Anastasakis E Papantoniou N Mesogitis S Theodora M Antsaklis A 《Acta obstetricia et gynecologica Scandinavica》2007,86(2):223-227
BACKGROUND: All cases of obstetric hysterectomies that were performed in our hospital during a seven-year study period were reviewed in order to evaluate the incidence, indications, risk factors, and complications associated with emergency obstetric hysterectomy. METHODS: Medical records of 45 patients who had undergone emergency hysterectomy were scrutinized and evaluated retrospectively. Maternal age, parity, gestational age, indication for hysterectomy, the type of operation performed, estimated blood loss, amount of blood transfused, complications, and hospitalization period were noted and evaluated. The main outcome measures were the factors associated with obstetric hysterectomy as well as the indications for the procedure. RESULTS: During the study period there were 32,338 deliveries and 9,601 of them (29.7%) were by cesarean section. In this period, 45 emergency hysterectomies were performed, with an incidence of 1 in 2,526 vaginal deliveries and 1 in 267 cesarean sections. All of them were due to massive postpartum hemorrhage. The most common underlying pathologies was placenta accreta (51.1%) and placenta previa (26.7%). There was no maternal mortality. CONCLUSIONS: Obstetric hysterectomy is a necessary life-saving procedure. Abnormal placentation is the leading cause of emergency hysterectomy when obstetric practice is characterized by a high cesarean section rate. Therefore, every attempt should be made to reduce the cesarean section rate by performing this procedure only for valid clinical indications. 相似文献
10.
Parkinson’s disease is the second most common neurodegenerative disease and has currently no effective treatment, one that would be able to stop or reverse the loss of dopaminergic neurons in the substantia nigra pars compacta. In addition, Parkinson’s disease diagnosis is typically done when a significant percentage of the dopaminergic neurons is already lost. In neurodegenerative disorders, some therapeutic strategies could be effective only at inhibiting further degeneration; on the other hand, cell replacement therapies aim at replacing lost neurons, an approach that would be ideal for the treatment of Parkinson’s disease. Many cell replacement therapies have been tested since the 1970s in the field of Parkinson’s disease; however, there are still significant limitations prohibiting a successful clinical application. From the first fetal midbrain intrastriatal graft to the most recent conversion of astrocytes into dopaminergic neurons, we have gained equally, significant insights and questions still looking for an answer. This review aims to summarize the main milestones in cell replacement approaches against Parkinson’s disease. By focusing on achievements and failures, as well as on the additional research steps needed, we aim to provide perspective on how future cell replacement therapies treats Parkinson’s disease.Key Words: endogenous, neurodegenerative disease, neurogenesis, neurotrophic factors, Parkinson’s disease, stem cells, transdifferentiation, transplantations 相似文献