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81.
A screening tool (in Chinese) for maladaptive internet use was developed in two stages. Thirty-five factors were first extracted from data obtained from 378 adolescents with a 179-item questionnaire. Nine higher-order factors were then obtained from 35 factors. A 26-item screen that measures both endogenous and exogenous factors was constructed on the basis of the nine higher-order factors. The screen’s split-half validity and concurrent criterion-related validity were ascertained with a new sample of 3,523 adolescents. The screen may be used to classify adolescent internet-users into four categories. Its endogenous part may be used to identify potential problem internet users.  相似文献   
82.
This study was designed to examine the relationship between gambling behaviour (gambling frequency and problem gambling severity) and financial management practices (cash management, risk management, and general management), financial management attitudes, and money attitudes (materialism, achievement, budget, obsession, and anxiety) in a sample of 118 participants (45 males, 73 females) recruited from a university. The findings revealed that gambling frequency was not significantly associated with any financial management, financial attitude, or money attitude variable but that problem gambling severity was significantly positively associated with financial management attitudes and obsession and negatively associated with budget. However, problem gambling severity scores were no longer significantly correlated with these factors after controlling for demographic and socio-economic factors. It was concluded that future research evaluating multiple dimensions of practices and attitudes with reliable and valid standardised instruments in large community or clinical samples is required in order to design cognitive interventions for problem gambling that facilitate changes in general beliefs about the importance of money.  相似文献   
83.
The development of resistance to anticancer therapies is a major hurdle in preventing long-lasting clinical responses to conventional therapies in hormone-refractory prostate cancer. Herein, the molecular evidence documenting that bone metastasis microenvironment survival factors (mainly the paracrine growth hormone-independent, urokinase-type plasminogen activator-mediated increase of IGF-1 and the endocrine production of growth hormone-dependent IGF-1, mainly liver-derived IGF-1 production) produce an epigenetic form of prostate cancer cells that are resistant to proapoptotic therapies is reviewed. Consequently, the authors present the conceptual framework of a novel antibone microenvironment survival factor, mainly an anti-IGF-1 hormonal manipulation for androgen ablation refractory prostate cancer (a combination of conventional androgen ablation therapy [luteinising hormone-releasing hormone agonist-A or orchiectomy]) with dexamethasone plus somatostatin analogue, which yielded durable objective responses and major improvement of bone pain and performance status in stage D3 prostate cancer patients.  相似文献   
84.
STUDY OBJECTIVE: To determine whether prophylactic amiodarone, dosed according to Atrial Fibrillation Suppression Trial (AFIST) I and II regimens, is a cost-effective strategy for prevention of postoperative atrial fibrillation. DESIGN: Cost-effectiveness analysis of retrospective cohort study. SETTING: Urban, academic hospital. PATIENTS: A total of 2046 patients who underwent cardiothoracic surgery between February 1, 1998, and October 31, 2003. Of these patients, 186 received amiodarone and 1860 served as controls. MEASUREMENTS AND MAIN RESULTS: Each patient who received prophylactic amiodarone using the AFIST I or II dosing strategies was matched for age, sex, history of valvular surgery, history of atrial fibrillation, beta-blocker intolerance, and receipt of preoperative digoxin therapy with 10 patients who did not receive prophylactic amiodarone. Occurrence of postoperative atrial fibrillation, total hospital costs, and both intensive care unit (ICU) and total hospital length of stay (LOS) were compared between groups. Nonparametric bootstrapping was conducted to examine study results as part of a quadrant analysis and to calculate confidence intervals for the incremental cost-effectiveness ratio. The ICU and total hospital LOS, and total costs for patients with and without postoperative atrial fibrillation were also compared. Fewer patients receiving prophylactic amiodarone developed postoperative atrial fibrillation compared with controls (23.1% vs 29.9%, p=0.05). Total hospital costs for the amiodarone group were 28% less than those for the control group (24,131 US dollars +/- 26,539 vs 33,518 US dollars +/- 40,892, p=0.002). Approximately 98% of the time, patients receiving amiodarone prophylaxis fell into the quadrant that showed superior efficacy and lower total costs. Patients who developed postoperative atrial fibrillation, compared with those who did not, regardless of amiodarone prophylaxis, had a longer mean +/- SD stay in the ICU (6.9 +/- 17.1 vs 3.7 +/- 7.9 days, p<0.001), a longer mean total hospital LOS (14.8 +/- 18.8 vs 10.2 +/- 10.4 days, p+/-0.001), and higher mean total hospital costs (41,574 US dollars +/- 54,721 vs 28,968 US dollars +/- 31,046, p<0.001). CONCLUSION: Prophylactic amiodarone was shown to reduce the occurrence of postoperative atrial fibrillation as well as total hospital costs in patients undergoing cardiothoracic surgery. In patients who developed postoperative atrial fibrillation, both ICU and total hospital LOS as well as total hospital costs were increased.  相似文献   
85.
Myelodysplastic syndrome (MDS) comprises a spectrum of heterogeneous diseases. Most patients present with ineffective hematopoiesis. The pathophysiology involves immune-mediated effects, cytokine dysregulation, and apoptosis, among others. We treated 14 transfusion-requiring patients with MDS, 10 with refractory anemia (RA) and four with RA with excess blasts (RAEB) with a 4-day course of antithymocyte globulin (ATG) followed by intermittent etanercept for 4 months. Among 13 evaluable patients, five are red blood cell and platelet transfusion independent for intervals extending beyond 2 years, and two have normalized their peripheral blood parameters. One additional patient showed a transient rise of platelet and neutrophil counts, for an overall response rate of 46%. Responding patients showed striking improvements in marrow cell abnormalities as characterized by flow cytometry. These data show that a combination of ATG plus etanercept offers effective palliative therapy for unselected patients with MDS. Further trials incorporating these two agents are warranted.  相似文献   
86.
87.
We have previously shown alpha-melanocyte stimulating hormone to protect melanocytes and melanoma cells from the proinflammatory actions of tumor necrosis factor-alpha. The aim of the study was to extend this work to look into the influence of tumor necrosis factor-alpha on melanoma cell attachment, invasion, and integrin expression and ask to what extent alpha-melanocyte stimulating hormone might protect cells from tumor necrosis factor-alpha stimulation of increased integrin expression. HBL human melanoma cells were studied under resting and stressed conditions using tumor necrosis factor-alpha as a proinflammatory cytokine. Functional information on the actions of tumor necrosis factor-alpha on melanoma cells was obtained by examining the strength of attachment of melanoma cells to substrates and the ability of melanoma cells to invade through fibronectin. alpha3, alpha4, and beta1 integrin expression was detected by Western immunoblotting and the ability of alpha-melanocyte stimulating hormone to oppose the actions of tumor necrosis factor-alpha was studied on HBL cell attachment, invasion, and integrin subunit expression. Our results show that tumor necrosis factor-alpha increases the number of melanoma cells attaching to collagen (types I and IV) and tissue culture polystyrene, increases ability to invade through fibronectin, and upregulates the expression of alpha3 (28%), alpha4 (90%), and beta1 (65%) integrin subunit expression. In contrast, alpha-melanocyte stimulating hormone reduced cell attachment, invasion, and integrin expression and opposed the stimulatory effects of tumor necrosis factor-alpha. In conclusion this study provides further evidence of alpha-melanocyte stimulating hormone acting to "protect" melanoma cells from proinflammatory cytokine action. Our data support a hypothesis that an inflammatory environment would promote melanoma invasion and that the anti-invasive actions of alpha-melanocyte stimulating hormone are consistent with its working in an anti-inflammatory capacity.  相似文献   
88.
12-O-tetradecanoylphorbolacetate (TPA) influences proliferation, differentiation, and apoptosis in a variety of cells including prostate cancer cells. Here, we show that androgen treatment potentiates TPA-induced apoptosis in androgen-sensitive prostate cancer LNCaP cells but not in androgen-independent prostate cancer cell lines DU145 and PC-3. The use of the antiandrogen bicalutamide (Casodex) rescued LNCaP cells from 5-alpha-dihydrotestosterone (DHT)/TPA-induced apoptosis, suggesting that DHT/TPA-induced apoptosis is mediated by androgen/androgen receptor (AR). In addition, a caspase-3 inhibitor (Ac-DEVD-CHO) reduced the level of apoptosis, suggesting that DHT/TPA-mediated apoptosis occurs through a caspase-3-dependent pathway. A functional reporter assay using nuclear factor (NF) kappaB-luciferase and an electromobility gel shift assay showed that DHT suppressed NFkappaB activity. In addition, apoptosis mediated by combined DHT/TPA treatment was abrogated by overexpression of the NFkappaB subunit p65 in LNCaP-p65 cells, suggesting that NFkappaB may play an important role in regulating the effects of androgen/AR and TPA on apoptosis. Furthermore, use of the c-Jun N-terminal kinase (JNK) inhibitor SB202190 showed that the combination of DHT/TPA increased JNK activation in LNCaP cells but not in LNCaP-p65 cells, demonstrating that NFkappaB may be able to suppress JNK activity. These results indicate that androgen/AR facilitates TPA-induced apoptosis by interruption of the NFkappaB signaling pathway, leading to activation of JNK in LNCaP cells. These data describe a signaling pathway that could potentially be useful in proposed therapeutic treatment strategies exploiting combinations of different agents that control apoptosis in prostate tumors.  相似文献   
89.
Peritoneal dialysis in the nursing home   总被引:2,自引:0,他引:2  
Background: During the past few decades, the demographics of end stage renal disease have been changed significantly with the emerging predominance of elderly patients. Elderly dialysis patients are usually more dependent and may need long-term placement in a long-term care facility. Failure to meet the needs of these patients may have a significant impact on the peritoneal dialysis program. We report our experience of starting peritoneal dialysis program in a community-based Long Term Care Facility (LTCF).Methods: During the period of 2000–2001, after appropriate training of nursing home personnel, we admitted 8 peritoneal dialysis patients to one community-based nursing home. All information presented here has been collected through chart review.Results: At the time of admission the average age of the 8 patients was 77.3 ± 7.2 years (range 69 to 91 years). All patients had several comorbid diseases and six of the eight were bed-ridden. The patients stayed in the facility for a total of 29.57 patient months. One patient had three episodes of peritonitis within three months (all culture negative) and has been excluded from the analysis of the overall peritonitis rate. The peritonitis rate for the other seven patients was 1 per 7.54 patient month. Six patients were readmitted to hospital because of peritonitis [4], severe malnutrition [1] and hip fracture [1]. Four of them died in the hospital. One died in the nursing home. One patient remains in the nursing home at the present time.Conclusions: Our experience suggests that peritoneal dialysis can be achieved in a community-based nursing home. This requires a systematic training program for the LTCF personnel and the availability of a ``dedicated' nephrology dialysis staff. This is crucial to the success of the program. It is important that patients, their families and ESRD care professionals are informed of the limited survival expectation particularly for very old and severely impaired patients.  相似文献   
90.
Treatment results for malignant skull base lesions may be improved with combined modality therapy. Using a novel drug infusion technique that capitalizes on the pharmacodynamic cisplatin-neutralizing properties of thiosulfate, 14 patients (6 untreated, 8 recurrent) received cisplatin (120 to 200 mg/m(2) for 1 to 4 weeks x 2-4 cycles) as part of a multimodality treatment program. Histology included squamous cell carcinoma, 11 patients (8 upper aerodigestive tract, 3 cutaneous); sarcoma, 2 patients (malignant fibrous histiocytoma, synovial cell sarcoma); and salivary gland cancer, 1 patient. The lesions involved the lateral skull base (12 patients) and the anterior (2 patients).Dose intensities for cisplatin were between 33.3 and 200 mg/m(2)/wk. Major responses occurred in 9/14 patients (64.3%), 3 of whom had complete responses. Drug toxicity, occurring in 11 patients, was mild and there were no significant complications as a result of the infusions. Eleven patients subsequently underwent surgical resections. The mean survival time is 23.3 months. Eight patients are alive without disease, 2 alive with disease, and 4 are dead of disease.The effectiveness of this highly selective supradose cisplatin infusion technique and its low morbidity support continued investigations of its application to patients with cranial base malignancies.  相似文献   
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