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Human chronic myelogenous leukemia (CML) is a malignancy of pluripotent hematopoietic cells characterized by a distinctive cytogenetic abnormality resulting in the creation of a p210 Bcr-Abl fusion protein with abnormal tyrosine kinase activity. Recently, a selective Abl kinase inhibitor, Imatinib mesylate, was introduced as a first line therapy for CML. Despite the initial response, CML patients develop a resistantance to Imatinib, which is mediated mainly by point mutations within the Abl protein. Herein, we describe the identification of mycelium organic extracts of Daedalea gibbosa with selective anti-proliferating and apoptosis-inducing activities against K562 cells and other laboratory model of CML. Using activity-guided purification, we isolated an active fraction, F6, which inhibits in vitro kinase activity of recombinant Abl. The active fraction significantly inhibits the autophosphorylation of native and mutated Bcr-Abl, which are resistant to Imatinib treatment including the T315I mutation. Using a colony-forming assay, we demonstrated that the active fraction is effective in inhibiting the colony formation of the Ba/F3 cell line harboring either native Bcr-Abl or its mutations, including the T315I mutation. Our data illustrated the potential of natural products in cancer therapeutics.  相似文献   
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Background Breast cancer and obesity represent important public health issues in most western countries. A number of studies found a negative prognosis effect of obesity or excess of weight in woman breast cancer. However, to date, this issue remains controversial. The objectives of this study were to confirm the prognosis role of obesity on a large cohort of patients and to investigate a potential independent effect. Materials and methods We constituted a cohort of 14,709 patients who were recruited and treated at the Curie Institute (Paris) from 1981 to 1999. These patients were followed prospectively for a first unilateral invasive breast cancer without distant metastasis. Obesity was defined by a Body Mass Index (BMI) above 30 kg/m(2) according to the World Health Organization recommendations. Results Obese patients (8%) presented more extended tumors at diagnosis time suggesting a delayed breast cancer diagnosis. However, obesity appeared as a negative prognosis factor for several events in respectively univariate and multivariate survival analysis: metastasis recurrence (HR = 1.32[1.19-1.48]; HR = 1.12[1.00-1.26]), disease free interval (1.20[1.08-1.32]; 1.10[0.99-1.22]), overall survival (1.43[1.28-1.60]; 1.12[0.99-1.25]) and second primary cancer outcome (1.57[1.19-2.07]; 1.43[1.09-1.89]). Even if obese patients presented more advanced tumors at diagnosis time, multivariate analysis showed that there was a relevant independent effect. Other BMI codings, distinguishing overweight patients or using BMI as a continuous variable, showed a consistent correlation between BMI's value and prognosis effect. Interaction analysis revealed a more important obesity effect in the presence of tumor estrogen receptors and among limited extent tumors. Conclusions This survey confirms the prognosis role of obesity on one of the largest cohort by investigating several prognosis events. While independent obesity effect linked to hormonal disorders appeared consistent as obesity's mechanism, we stress that obesity prognosis effect was also related to breast cancer presentation at diagnosis time.  相似文献   
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In a 55-year-old woman with classic migraine, paresis of the superior division of the right oculomotor nerve occurred twice after subcutaneous injections of sumatriptan. Each paresis disappeared within 2 weeks. Magnetic resonance imaging of the head was normal. Sumatriptan injections were discontinued, and ocular motility problems ceased. Use of sumatriptan for migraine should be considered in the diagnosis of transient, pupil-sparing, oculomotor nerve palsies in the absence of other microvascular risk factors.  相似文献   
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The effects of the phencyclidine derivative, N-[1-(2-benzo(b)thiophenyl)cyclohexyl]piperidine (BTCP), on the electrical activity of noradrenaline (NA) neurons of the locus coeruleus (LC) were studied in halothane-anesthetized rats. Systemic administration of BTCP potently inhibited LC neurons (ID50 of 1.1 +/- 0.1 mg/kg i.v.). This effect was mimicked by local microejection of BTCP into the LC. Both the systemic and local effects of BTCP were blocked by alpha 2-adrenoceptor antagonists and prevented by prior depletion of catecholamines with reserpine. These and other data suggest that BTCP behaves as a potent indirect NA agonist (i.e. via NA re-uptake and/or release systems).  相似文献   
106.
IntroductionAppropriate prescribing of thromboprophylaxis according to guidelines’ recommendations can heighten over- or underutilization risk. The study intended to evaluate the safety and effectiveness of appropriate/inappropriate thromboprophylaxis use among hospitalized elderly medical patients.MethodsA retrospective observational cohort study was conducted, including patients who were ≥60 years old, hospitalized for an acute medical illness that required hospitalization in a medical ward for >48 h, and received thromboprophylaxis. Against the American College of Chest Physicians guidelines, the thromboprophylaxis use appropriateness was assessed.ResultsA total of 370 patients met the inclusion criteria, in 71.9% of whom thromboprophylaxis use was appropriate. The mean age of the included patients was 75 years (±9.1), and 72.4% of them were at high risk of venous thromboembolism (VTE), and almost all these patients received appropriate thromboprophylaxis. The occurrence of bleeding was significantly higher in the appropriate use group during hospitalization than the inappropriate use group (11.7% vs. 2.9%, p = 0.009); the majority of these bleeding events were classified as major. There were no differences in VTE events during hospitalization or 90 days all-cause mortality between the two groups.ConclusionThe study demonstrates high prescribers’ compliance with recommendations in high-risk patients. In patients at low risk for VTE, the overutilization of thromboprophylaxis did not increase their bleeding risk. This study suggests that the benefits of thromboprophylaxis in elderly patients, regardless of their VTE risk, may outweigh the risk of bleeding.  相似文献   
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Health Care Management Science - Around the world, cancer care services are facing many operational challenges. Operations management research can provide important solutions to these challenges,...  相似文献   
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Purpose

To compare the effectiveness of femtosecond laser (FSL) assisted and manual arcuate keratotomy (AK) procedures for the correction of postkeratoplasty astigmatism.

Methods

Fifty-two eyes (52 patients) were treated with FSL assisted AK and 53 eyes (51 patients) with manual AK for post-keratoplasty astigmatism. The main outcome measures included preoperative and postoperative manifest refraction, uncorrected and corrected distance visual acuity (UDVA, CDVA), corneal topography and complications.

Results

In FSL group, UDVA changed significantly from 0.90?±?0.43 preoperatively to 0.60?±?0.39 at last follow-up (p?=?0.001). In manual group, preop- (0.87?±?0.35) and post-operative UDVA (0.93?±?042) were comparable (p?=?0.535). CDVA improved from 0.30?±?0.18 preoperatively to 0.20?±?0.14 at last follow-up visit in FSL group (0.014) and 0.28?±?0.15 preoperative to 0.23?±?0.19 at last postoperative visit (0.074) in manual group. Postoperative UDVA and CDVA were comparable between both the groups (p?>?0.05). The mean preoperative refractive cylinder was 6.38?±?3.73 and 7.15?±?132, decreasing significantly to 5.06?±?2.06 and 5.19?±?2.25 after manual and FSL assisted AK procedures respectively. Mean change in the refractive cylinder was ?1.10?±?4.11 in manual AK group and ?2.19?±?2.35 in FSL group (p?=?0.134). Perforation, overcorrection and regression occurred in respectively 3 eyes (5.8%), 12 eyes (23.07%) and 1 eye (1.92%) in FSL group and 1 eye (1.9%; macro-perforation), 7 eyes (13.21%) and 8 eyes (15.09%) in manual group. Additionally, in the manual group, severe ectasia occurred in 1 eye (1.9%).

Conclusion

FSL assisted AK procedure is comparable or to a certain extent better regarding safety and efficacy than manual AK procedure. Postoperatively, FSL resulted in better outcomes of UCVA, BCVA, refractive cylinder and keratometric astigmatism compared to the manual AK procedures; although, the difference between the groups was not statistically significant.  相似文献   
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