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161.
In this study, we target arginine auxotrophy of AML cell lines using human arginase I cobalt-PEG5000. HuArgI(Co)-PEG5000 was cytotoxic to all AML cell lines tested. Mononuclear cells and CD34+ blasts were not sensitive demonstrating the selectivity of HuArgI(Co)-PEG5000-induced arginine deprivation. Addition of l-citrulline led to the rescue of five cell lines. The four cell lines that were not rescued by l-citrulline did not express argininosuccinate synthetase-1, indicating complete arginine auxotrophy. Inhibition of autophagy increased cell sensitivity to HuArgI(Co)-PEG5000 demonstrating the protective role of autophagy following arginine deprivation.  相似文献   
162.
IntroductionCentral blood pressure (CBP) is the pressure exerted by the blood column at any given moment on the aortic and carotid artery walls, which is a close proxy for the blood pressure inside the brain and the heart, and is thus a better marker of cardiovascular morbidity and mortality than peripheral blood pressure (PBP).ObjectiveTo assess how the augmentation index (AI), peripheral pulse pressure (pPP), central pulse pressure (cPP) and subendocardial viability ratio (SEVR) vary in hypertensive patients according to level of control of CBP and PBP.MethodsWe performed an observational, cross-sectional study in a convenience sample from a general practice in Central Portugal over a period of four days in May 2010. Measurements were taken after a four-minute resting period. The following values were considered to reflect controlled pressures: PBP <140/90 mmHg, CBP <130/80 mmHg, pPP <55 mmHg and cPP <45 mmHg.ResultsThe sample included 92 patients, 38 male (41.3%), mean age 62.3±11.1 years, with no significant difference in gender distribution. PBP was controlled in 55 (59.8%), and CBP in 53 (57.6%). Both PBP and CBP were controlled in 50 patients (54.3%) and neither was controlled in 34 (37.9%). pPP and cPP were significantly lower in those with controlled PBP (p<0.001) and CBP (p<0.001). AI was non-significantly lower in those with controlled PBP (78±9 vs. 80.7) and those with controlled CBP (78±9 vs.81±7) (p=0.02). SEVR was within the desirable range in 92 patients (92.2%). 78.4% of individuals were taking drugs acting on the renin angiotensin aldosterone system (RAAS).ConclusionsIn a convenience sample of 92 patients, PBP and CBP were controlled in 59.8% and 57.6%, respectively. Those with controlled PBP had significantly better peripheral systolic and diastolic blood pressure, CBP, pPP and cPP; the same was true of those with controlled CBP, who also had a significantly better AI. The percentage of the cardiac cycle in diastole had a desirable value for 92,2% of the subjects.  相似文献   
163.
Monitoring of esophageal pH is a major component of the evaluation of gastroesophageal reflux disease. A recent innovation has led to the replacement of the intraluminal probe by a wireless capsule. This capsule is attached to the esophageal wall and transmits the appropriate data to a patient-worn receiver. After a short period of time the capsule detaches itself from the wall and is eliminated. We recently encountered a patient in which the capsule did not detach in a timely manner. It was imaged during a preoperative esophagogram.  相似文献   
164.
Developed countries throughout the world are challenged with the ageing of their labour force. In these societal contexts, low employment rates and early labour market exits of older employees are at stake, as well as arrangements for retirement, financial household considerations and mutual obligations between generations. Although proactive behaviour has been extensively studied, no research has addressed the proactive behaviour of older employees themselves when facing (re)hiring and retention versus early retirement. For the first time, this study tests the relationships of proactive behaviour with job-related affective well-being and anticipated retirement age in a sample of employees aged 50+ (N = 89) in Belgium. The findings are obtained by using a self-report questionnaire. Statistical analysis includes correlation and regression analysis. Major findings are that (i) proactive older employees feel energetic, enthusiastic, inspired, at ease, relaxed and satisfied; and (ii) later retirement is anticipated when experiencing positive affective well-being at study.  相似文献   
165.
166.
Objectives: The therapy of advanced, relapsed or refractory primary cutaneous lymphomas is often unsatisfactory. Recent data indicate a favourable pharmacokynetic, pharmacodynamic and toxicity profile of pegylated liposomal doxorubicin (Peg‐Doxo) in primary cutaneous T‐cell lymphomas, while in primary cutaneous B‐cell lymphomas (PCBCLs), the drug efficacy has never been assessed so far. Methods: We performed a prospective phase II pilot clinical trial of Peg‐Doxo monotherapy (20 mg/m2) in PCBCLs. One patient had a marginal zone B‐cell lymphoma and four were affected by diffuse large B‐cell lymphoma‐leg type, all with widespread nodular lesions. Results: All the patients achieved a complete response (CR = 100%) in a short period of time (median 3 months), even when pretreated with radio‐chemotherapy. Two experienced a relapse. At follow‐up, one patient died for progressive disease; four are in CR after 5, 52, 63 and 69 months. As concerning the toxicity profile, the treatment was well‐tolerated, no one decreased or delayed the dose. The haematological toxicity was mild with only one case of grade III neutropenia; a patient showed a grade I neurotoxicity. Dermatological toxicity, in particular the palmar–plantar erythrodysesthesia, did not occurred, probably because of both the low dosages of Peg‐Doxo monotherapy and the oral prophylaxis with pyridoxine. Conclusions: In spite of the small number of patients, it emerges that monochemotherapy with Peg‐Doxo has a significantly high clinical activity and a good safety profile in PCBCLs, even in aggressive forms, compared with other therapeutic regimens, which are completely reviewed. It suggests the need of further investigations in this field.  相似文献   
167.
Nowadays, twin gestation is increased due to advances in assisted reproduction. Unquestionably, these pregnancies have an increased risk of foetal and maternal disorders. Single foetal death has a different incidence depending on gestational age; in the first trimester between 10-70%, in the second and third trimester it is a rare event, 0.5-7%.  相似文献   
168.
The effects of troglitazone 400 or 600 mg/d on the glycemic control, very-low-density lipoprotein (VLDL), and high-density lipoprotein (HDL) subclass concentrations and plasminogen-activator inhibitor 1 (PAI-1) levels were assessed in patients with type 2 diabetes that had not been controlled with dietary treatment. This was a multicenter, open-label, parallel-groups study. It included a run-in 4-week diet period and a 24-week randomized treatment. Fifty one patients received 400 mg/d and 55 patients 600 mg. The mean HbA(1c) concentration at the end of the study was similar for both doses. Troglitazone, regardless of dose, significantly improved insulin sensitivity assessed by the homeostasis model (HOMA). PAI-1 levels were significantly decreased in both groups by 13%. Higher HDL cholesterol concentrations and lower triglycerides levels were observed at the end of treatment. Triglyceride contents were reduced only in the lighter VLDL1. The change in HDL cholesterol concentration resulted from a combination of increased HDL3 cholesterol and lower HDL2 cholesterol levels. No differences were found in the effects of both treatment groups on the evaluated parameters. Our data provide new information about the actions of the drug on the lipid profile. Troglitazone reduces triglyceride levels by lowering the triglycerides content of the VLDL1 particles and increases HDL cholesterol concentrations by increasing HDL3 cholesterol levels.  相似文献   
169.
OBJECTIVES: The purpose of this work was to determine the prognostic value of normal exercise myocardial perfusion imaging (MPI) tests and exercise echocardiography tests, and to determine the prognostic value of these imaging modalities in women and men. BACKGROUND: Exercise MPI and exercise echocardiography provide prognostic information that is useful in the risk stratification of patients with suspected coronary artery disease (CAD). METHODS: We searched the PubMed, Cochrane, and DARE databases between January 1990 and May 2005, and reviewed bibliographies of articles obtained. We included prospective cohort studies of subjects who underwent exercise MPI or exercise echocardiography for known or suspected CAD, and provided data on primary outcomes of myocardial infarction (MI) and cardiac death with at least 3 months of follow-up. Secondary outcomes (unstable angina, revascularization procedures) were abstracted if provided. Studies performed exclusively in patients with CAD were excluded. RESULTS: The negative predictive value (NPV) for MI and cardiac death was 98.8% (95% confidence interval [CI] 98.5 to 99.0) over 36 months of follow-up for MPI, and 98.4% (95% CI 97.9 to 98.9) over 33 months for echocardiography. The corresponding annualized event rates were 0.45% per year for MPI and 0.54% per year for echocardiography. In subgroup analyses, annualized event rates were <1% for each MPI isotope, and were similar for women and men. For secondary events, MPI and echocardiography had annualized event rates of 1.25% and 0.95%, respectively. CONCLUSIONS: Both exercise MPI and exercise echocardiography have high NPVs for primary and secondary cardiac events. The prognostic utility of both modalities is similar for both men and women.  相似文献   
170.
BACKGROUND: The pathophysiologic mechanisms that determine the severity of Mediterranean spotted fever (MSF) and the host-related and microbe-related risk factors for a fatal outcome are incompletely understood. METHODS: This prospective study used univariate and multivariate analyses to determine the risk factors for a fatal outcome for 140 patients with Rickettsia conorii infection admitted to 13 Portuguese hospitals during 1994-2006 with documented identification of the rickettsial strain causing their infection. RESULTS: A total of 71 patients (51%) were infected with the Malish strain of Rickettsia conorii, and 69 (49%) were infected with the Israeli spotted fever (ISF) strain. Patients were admitted to the intensive care unit (40 [29%]), hospitalized as routine inpatients (95[67%]), or managed as outpatients (5[4%]). Death occurred in 29 adults (21%). A fatal outcome was significantly more likely for patients infected with the ISF strain, and alcoholism was a risk factor. The pathophysiology of a fatal outcome involved significantly greater incidence of petechial rash, gastrointestinal symptoms, obtundation and/or confusion, dehydration, tachypnea, hepatomegaly, leukocytosis, coagulopathy, azotemia, hyperbilirubinemia, and elevated levels of hepatic enzymes and creatine kinase. Some, but not all, of these findings were observed more often in ISF strain-infected patients. CONCLUSIONS: Although fatalities and similar clinical manifestations occurred among both groups of patients, the ISF strain was more virulent than the Malish strain. Multivariate analysis revealed that acute renal failure and hyperbilirubinemia were most strongly associated with a fatal outcome.  相似文献   
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