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951.
BACKGROUND: Injuries due to falls are one of the most important public health concerns for all ages, but especially for frail elderly people. Although a small number of falls have a single cause, the majority have many different causes resulting from the interactions between intrinsic or extrinsic risk factors. METHODS: We conducted an observational study on data from a large population of community-dwelling elderly people to tests the hypothesis that the current use of different classes of psychotropic medications, including antipsychotic agents, benzodiazepines, nonbenzodiazepine sedative-hypnotics, and antidepressants, increases the risk for falls. We analyzed data from a large collaborative observational study group, the Italian Silver Network Home Care project, that collected data on patients admitted to home care programs (n = 2854). RESULTS: After adjusting for all potential confounders, users of any psychotropic drugs had an increased risk of fall of nearly 47% (adjusted odds ratio [OR], 1.47; 95% confidence interval [CI], 1.24-1.74). Similarly, compared with nonusers, users of atypical antipsychotic drugs also had an increased risk of falling at least once (OR, 1.45; 95% CI, 1.00-2.11). Among benzodiazepine users, patients taking agents with long elimination half-life (OR, 1.45; 95% CI, 1.00-2.19) and patients taking benzodiazepines with short elimination half-life (OR, 1.32; 95% CI, 1.02-1.72) had an increased risk of falls. Patients taking antidepressants did not show a higher risk of falling compared to nonusers (OR, 0.92; 95% CI, 0.83-1.41). CONCLUSIONS: Our data suggest that, among psychotropic medications, antipsychotic agents and benzodiazepines are associated with an increased risk of falls. Our findings do not support the hypothesis that preferential prescribing of short-acting benzodiazepines instead of long-acting agents or atypical antipsychotic medications instead of typical agents will substantially decrease fall risk associated with the use of these classes of drugs.  相似文献   
952.
When the term 'angioblast' was initially used, almost a century ago, the cells bearing this name were thought to give rise to plasma, red blood cells and endothelium, with new blood vessels arising from 'within the (cell) bodies of these angioblasts'. More recently, putative circulating 'progenitor endothelial cells', often also referred to as angioblasts, were first described in the adult human a mere decade ago. Therefore, while our understanding of progenitor cell biology and other relevant vascular developmental programs has progressed enormously, key terms such as 'angioblast' and 'angiogenesis' have remained constant. With the recent intense interest in angioblasts and endothelial progenitor cells, and their potential with respect to cardiovascular regenerative medicine, our knowledge of how these and other nonprogenitor cells might contribute to new vessel formation has taken a further leap in understanding. In this review, we focus on the controversial use and definition of these terms based upon our current understanding of vascular biology and progenitor cells.  相似文献   
953.
Background  Little is known about how Latinos with post-traumatic stress disorder (PTSD) understand their illness and their preferences for mental health treatment. Objective  To understand the illness beliefs and treatment preferences of Latino immigrants with PTSD. Design  Semi-structured, face-to-face interviews. Participants  Sixty foreign-born, Latino adults recruited from five primary care centers in New York and New Jersey and screened for PTSD. Approach  Content analytic methods identified common themes, their range, and most frequent or typical responses. Results  Participants identified their primary feelings as sadness, anxiety, nervousness, and fear. The most common feeling was “sad” (triste). Other words frequently volunteered were “angry” (enojada), “nervous” (nerviosa), and “scared” (miedo). Participants viewed their PTSD as impairing health and functioning. They ascribed their somatic symptoms and their general medical problems to the “stress” from the trauma and its consequences on their lives. The most common reason participants volunteered for their work and school functioning being impaired was their poor concentration, often due to intrusive thoughts. Most expressed their desire to receive mental health treatment, to receive it within their primary care center, and preferred psychotherapy over psychotropic medications. Among participants who did not report wanting treatment, most said it was because the trauma was “in the past.” Conclusions  Clinicians may consider enquiring about PTSD in Latino patients who report feeling sad, anxious, nervous, or fearful. Our study suggests topics clinicians may include in the psychoeducation of patients with PTSD.  相似文献   
954.
955.
BACKGROUND: A persistent left superior vena cava (SVC) can be an arrhythmogenic source in patients with atrial fibrillation (AF) through connections from the coronary sinus (CS) and the left atrium (LA). The left SVC can be electrically isolated. However, little clinical data about the impact of left SVC disconnection on AF outcome are available. We report on six patients with left SVC and recurrent AF. OBJECTIVES: The purpose of this study was to assess the impact of left SVC isolation on AF recurrence. METHODS: Six patients (4 men and 2 women; age 50 +/- 6.4 years) with symptomatic drug-refractory AF and persistent left SVC presented to our laboratory for treatment. Four of the patients had left SVC isolation only because there was no conduction recovery in the pulmonary veins (PVs) after several previous procedures. RESULTS: Conduction between the left SVC and the CS and LA was documented, as was spontaneous ectopies in three patients that degenerated into AF in one patient. Isolation of the left SVC was successful in all patients. Isolation was relatively easy to perform (10.25 +/- 1.6 minutes), with no complications. After follow-up of 13 +/- 7.4 months, all patients were in sinus rhythm and free from AF without antiarrhythmic drugs. CONCLUSION: This study stresses the importance of looking for unusual sources of AF in patients presenting for repeat procedures or in those in whom the PVs have been ruled out as a source triggering AF. We present clinical evidence that in patients with AF and left SVC, isolation of the PVs only may not be sufficient to suppress AF. Thus, diagnosis and isolation of the left SVC appears critical to preventing AF recurrence in patients with AF when ablation is considered.  相似文献   
956.
We investigated the feasibility and efficacy of high-dose vincristine (4 mg/m2 over 4 d) combined with fractionated total body irradiation (F-TBI) (200 cGyx2 over 3 d) and cyclophosphamide (60 mg/kg for 2 d) as a preparative regimen in allogeneic (AlloBMT) and autologous (ABMT) bone marrow transplantation for 75 consecutive children (median age at transplant 8-5 years) with acute lymphoblastic leukaemia in second complete remission (CR). Median duration of first CR was 26 and 25 months in the AlloBMT and ABMT group, respectively. Of the 46 patients who underwent AlloBMT, 33 had isolated or combined marrow relapse and 13 isolated extramedullary relapse. Of the 29 patients given ABMT, 23 had preBMT isolated or combined marrow relapse and six isolated extramedullary relapse. 44/75 patients are alive and in CR at a median follow-up of 35 months (range 10-90 months). Seven children given AlloBMT (15.8%) and two given ABMT (7%) died from transplant-related causes. No major early organ toxicity, including vincristine-related toxicity, was recorded. The overall 3-year EFS estimate (95% CL) was 53.8% (42-66%): in particular, 58.2% (40-76%) for AlloBMT and 27.6% (9-46%) for ABMT patients who experienced a marrow relapse before transplant. The overall 3-year relapse rate estimate (95% CL) was 39.2% (27-51%): in particular, 30.1% (12-49%) in the AlloBMT group and 72% (54-91%) in the ABMT group ( P < 0.01) who presented a preBMT isolated or combined marrow relapse. We conclude that the conditioning regimen with high-dose vincristine combined with cyclophosphamide and F-TBI is feasible and promising, although its therapeutic advantage should be tested in larger series of patients enrolled in randomized studies.  相似文献   
957.
BACKGROUND: Catheter ablation has significantly transformed the clinical management of atrial fibrillation (AF). The safety and efficacy of this procedure are not well understood in patients with pacemakers and defibrillators. OBJECTIVES: The purpose of this study was to study the impact of radiofrequency catheter ablation of AF in patients with pacemakers and implantable cardiac defibrillators. METHODS: We studied 86 patients with pacemakers and defibrillators (group I) and a similar number of age- and gender-matched controls (group II) who underwent AF ablation between 1999 and 2004. Clinical and procedural variables were compared between the two groups. In group I, various generator and lead parameters were compared before and after the procedure. Resurgence of clinical AF after 2 months was considered recurrence. RESULTS: Both groups were similar with regard to age, gender, body mass index, and type of AF. Group I had a higher incidence of diabetes (17% vs 6%, P = .03), coronary artery disease (25% vs 13%, P = .05), less prolonged AF (31 +/- 21 vs 45 +/- 30 months, P <.001), lower left ventricular ejection fraction (49 +/- 13% vs 52 +/- 9%, P = .03), and left ventricular end-diastolic dimensions (4.97 +/- 0.81 vs 4.72 +/- 0.67, P = .03). No changes in the sensing and pacing thresholds, impedance of atrial and ventricular leads, or defibrillator coil impedance after AF ablation were observed in group I. Atrial lead dislodgment was seen in two patients. Transient abnormal but "expected" pulse generator behavior was seen in 25% of patients without permanent malfunction. Stroke (1% vs 1%, P = 1.000), pulmonary vein stenosis (2% vs 1%, P = .77), and AF recurrence rates at 12 months were similar between groups I and II, respectively (19% vs 21%, P = .73). CONCLUSION: AF ablation is safe and efficacious in patients with pacemakers and defibrillators.  相似文献   
958.
BACKGROUND/AIM: The pathophysiology of osteoporosis in chronic liver diseases is unknown. Recent data suggest that serum leptin is associated with bone mineral density (BMD). In animal studies leptin was found to be a potent inhibitor of bone formation. We investigated the relationship between serum leptin levels, soluble leptin receptor (sOB-R), free leptin index (FLI) and BMD in patients with primary biliary cirrhosis (PBC). PATIENTS AND METHODS: Ninety-four female patients with PBC were included in this study; 122 healthy women served as controls. Serum leptin levels were measured by radioimmunoassay, sOB-R by enzyme-linked immunosorbent assay. BMD was measured by dual energy X-ray absorptiometry in the lumbar spine and femoral neck. RESULTS: Serum leptin was significantly lower in patients with PBC compared with healthy controls. No difference was found between the body mass index (BMI) of patients and controls. There was a strong positive correlation between leptin and BMI. In PBC no association was found between leptin, sOB-R and liver function tests, histological stages or the presence of osteoporosis. Osteoporosis was present in 38 patients. A positive correlation was found between serum leptin and femoral neck z-score even after adjustment for BMI, whereas serum sOB-R correlated inversely with the serum leptin level. There was no difference in FLI between the subgroups of PBC patients according to the stages of the disease. CONCLUSIONS: We found a lower serum leptin level and a higher sOB-R in patients with PBC, which could not be explained by the difference in BMI. As leptin was associated with BMD, it may be hypothesized that leptin is involved in the complex regulation of bone metabolism in PBC.  相似文献   
959.
960.
The plant growth hormone auxin plays a critical role in the initiation of lateral organs and meristems. Here, we identify and characterize a mutant, sparse inflorescence1 (spi1), which has defects in the initiation of axillary meristems and lateral organs during vegetative and inflorescence development in maize. Positional cloning shows that spi1 encodes a flavin monooxygenase similar to the YUCCA (YUC) genes of Arabidopsis, which are involved in local auxin biosynthesis in various plant tissues. In Arabidopsis, loss of function of single members of the YUC family has no obvious effect, but in maize the mutation of a single yuc locus causes severe developmental defects. Phylogenetic analysis of the different members of the YUC family in moss, monocot, and eudicot species shows that there have been independent expansions of the family in monocots and eudicots. spi1 belongs to a monocot-specific clade, within which the role of individual YUC genes has diversified. These observations, together with expression and functional data, suggest that spi1 has evolved a dominant role in auxin biosynthesis that is essential for normal maize inflorescence development. Analysis of the interaction between spi1 and genes regulating auxin transport indicate that auxin transport and biosynthesis function synergistically to regulate the formation of axillary meristems and lateral organs in maize.  相似文献   
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