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81.
Surfactants have long been known to have microbicidal action and have been extensively used as antiseptics and disinfectants for a variety of general hygiene and clinical purposes. Among surfactants, quaternary ammonium compounds (QAC) are known to be the most useful antiseptics and disinfectants. However, our previous toxicological studies showed that QAC are also the most toxic surfactants for mammalian cells. An understanding of the mechanisms that underlie QAC toxicity is a crucial first step in their rational use and in the design and development of more effective and safer molecules. We show that QAC-induced toxicity is mediated primarily through mitochondrial dysfunction in mammalian columnar epithelial cell cultures in vitro. Toxic effects begin at sublethal concentrations and are characterized by mitochondrial fragmentation accompanied by decreased cellular energy charge. At very low concentrations, several QAC act on mitochondrial bioenergetics through a common mechanism of action, primarily by inhibiting mitochondrial respiration initiated at complex I and, to a lesser extent, by slowing down coupled ADP phosphorylation. The result is a reduction of cellular energy charge which, when reduced below 50% of its original value, induces apoptosis. The lethal effects are shown to be primarily a result of this process. At higher doses (closer to the critical micellar concentration), QAC induce the complete breakdown of cellular energy charge and necrotic cell death.  相似文献   
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OBJECTIVE: To evaluate the clinical usefulness of serum vascular endothelial growth factor (VEGF) levels in gastric cancer patients. SUMMARY BACKGROUND DATA: Vascular endothelial growth factor plays an important role in the formation of new blood vessels involved in the growth and metastatic spread of solid tumors, but there is limited information regarding the clinical significance of serum VEGF levels in cancer patients. METHODS: Serum VEGF concentrations were measured by an enzyme linked immunosorbent assay in 61 healthy controls and in 58 gastric cancer patients before surgery, and then again at 7 and 30 days after surgery. The association between preoperative serum VEGF levels, clinicopathological features and patient survival, and their changes following surgery were evaluated. RESULTS: Serum VEGF levels in gastric cancer patients were significantly higher than those in controls. There was a significant association between serum VEGF levels and disease stage, as well as invasion depth of the tumor and the presence of distant metastases. Serum VEGF levels decreased significantly after radical resection of the primary tumor and increased in patients with unresectable tumors. Multivariate regression analysis showed that serum VEGF level is an independent prognostic factor for survival. CONCLUSIONS: Serum VEGF levels in gastric patients are significantly higher compared with normal controls and correlate with local tumor extent, disease stage, and the presence of distant metastases. Preoperative serum VEGF concentration decreases significantly after radical resection of the primary tumor and is an independent prognostic factor for patient survival suggesting that determination of serum VEGF levels may be clinically useful.  相似文献   
85.
Despite the enormous progress that has been madein the fields of vascular surgery and intensive care, reconstructive surgery of renal arteries in the presence of arteriosclerosis of the abdominal aorta remains a serious therapeutic problem and is associated with a high rate of complications. The purpose of this study was to analyze the results of treatment of patients with renovascular hypertension and so-called difficult aorta. Surgery was carried out in 68 patients with a critically stenosed renal artery and severe arteriosclerosis of the abdominal aorta. In 53 patients an aortobifemoral prosthetic graft was implanted together with endarterectomy of the renal artery in 23 patients, an aortorenal venous graft in 23 patients and a prosthetic graft in 7 patients. In the remaining 15 patients extra-anatomic anastomoses were performed between the splenic artery and the renal artery (7 patients), hepatic artery and renal artery (6) and between the superior mesenteric and renal artery (2). Postoperatively, the hypertension was cured in 55% of patients, improved in 38% and remained unchanged in 7%. After 1 year the results were respectively 47, 36, and 17%. The patients with an aortorenal prosthetic graft demonstrated a greater tendency for hypertension to recur.  相似文献   
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Background Breast-conservation surgery plus radiotherapy has become the standard of care for early-stage breast cancer; we evaluated its long-term complications. Methods We selected patients treated with surgery and radiotherapy between January 1990 and December 1992 (an era in which standard radiation dosages were used) with follow-up for at least 1 year. Patients were prospectively monitored for treatment-related complications. Median follow-up time was 89 months. Results A total of 294 patients met the selection criteria. Grade 2 or higher late complications were identified in 29 patients and included arm edema in 13 patients, breast skin fibrosis in 12, decreased range of motion in 4, pneumonitis in 2, neuropathy in 2, fat necrosis in 1, and rib fracture in 1. Arm edema was more common after lumpectomy plus axillary node dissection than after lumpectomy alone. Arm edema occurred in 18% of patients who underwent surgery plus irradiation of the lymph nodes and 10% who underwent surgery without nodal irradiation. Conclusions Breast-conservation surgery plus radiotherapy was associated with grade 2 or higher complications in only 9.9% of patients. Half of these complications were attributable to axillary dissection, it is hoped that lower complication rates can be achieved with sentinel lymph node biopsy.  相似文献   
87.
Background Insular thyroid carcinoma was described as a tumor with aggressive behavior, and patients usually present themselves with an advanced tumor stage. Whether the insular component is an independent factor for poor prognosis remains unclear. Therefore, in the present study, we compared the survival of patients with advanced insular, follicular, and papillary thyroid cancer. Materials and methods The clinical behavior of tumors in three groups of patients with T4 thyroid carcinoma—8 patients with insular, 11 patients with follicular, and 21 patients with papillary thyroid carcinomas—was compared. Disease-free survival and disease-specific death were analyzed statistically. Cox regression analysis was used to evaluate the influence of histotype and other prognostic factors. Results At 3 years, survival was 37.5% (mean 26 months) among patients with insular thyroid carcinoma, 80% (mean 59 months) among those with follicular, and 89% (mean 126 months) among those with papillary thyroid carcinomas (p = 0.007). Disease-free survival in patients without initial distant metastasis was worst in patients with insular thyroid carcinoma (20%) compared to those with follicular (75%) and those with papillary thyroid carcinomas (71%). Conclusion Patients with advanced insular thyroid carcinoma have a poorer outcome in comparison to patients with similar advanced stage who have follicular or papillary thyroid carcinoma.  相似文献   
88.
In middle resource countries (MRCs), cancer control programs are becoming a priority as the pattern of disease shifts from infectious diseases to non-communicable diseases such as breast cancer, the most common cancer among women in MRCs. The Middle Resource Scenarios Working Group of the BHGI 2010 Global Summit met to identify common issues and obstacles to breast cancer detection, diagnosis and treatment in MRCs. They concluded that breast cancer early detection programs continue to be important, should include clinical breast examination (CBE) with or without mammography, and should be coupled with active awareness programs. Mammographic screening is usually opportunistic and early detection programs are often hampered by logistical and financial problems, as well as socio-cultural barriers, despite improved public educational efforts. Although multidisciplinary services for treatment are available, geographical and economic limitations to these services can lead to an inequity in health care access. Without adequate health insurance coverage, limited personal finances can be a significant barrier to care for many patients. Despite the improved availability of services (surgery, pathology, radiology and radiotherapy), quality assurance programs remain a challenge. Better access to anticancer drugs is needed to improve outcomes, as are rehabilitation programs for survivors. Focused and sustained government health care financing in MRCs is needed to improve early detection and treatment of breast cancer.  相似文献   
89.

Background  

The determination of factors affecting curve flexibility is important in idiopathic scoliosis patients with regard to the Risser sign. The objective of this retrospective study was to identify factors affecting curve flexibility in patients with skeletally immature and mature idiopathic scoliosis.  相似文献   
90.
Introduction: Multi‐disease community health campaigns can be effective for population‐wide HIV testing in a research setting (SEARCH: NCT01864603). We sought to evaluate feasibility and uptake of a community‐led health campaign (CLHC) planned and implemented by village leaders and local clinic workers in Uganda. Methods: Over five months in 2014, locally elected village leaders and Ministry of Health (MoH) clinic staff in a rural parish in Uganda planned a census followed by a CLHC, after training by two SEARCH trial consultants and by leaders from a neighbouring parish that had previously participated in a SEARCH health campaign. We defined feasibility as: (1) elected leaders’ participation in training and implementation of pre‐campaign census and mobilization activities; (2) implementation of all campaign activities by MoH‐funded, local clinic staff; and (3) community participation in the campaign, including point‐of‐care screening for HIV, malaria, hypertension and diabetes, and same‐day referral for male circumcision and family planning (FP). Costing of all salaries and supplies was conducted. Results: Elected leaders from all eight villages in the parish participated in CLHC training. They and local clinic staff met monthly to select and plan CLHC services. Village leaders then leveraged existing volunteer health teams to perform a door‐to‐door census, enumerating 5,202 parish residents over 2 weeks. 2,753 (53%) residents participated in the 6‐day CLHC. Of 1,584 adult participants, 1,474 (93%) tested for HIV: 105/1,474 (7.1%) tested HIV positive. 27% (751/2,753) of participants reported fever and underwent malaria rapid diagnostic testing: 5.3% (40/751) tested positive. Among adults screened, 19% (271/1,452) were hypertensive, and 3% (18/637) had a random blood sugar >11.1 mmol/L. Of 805 men and boys (>10 years), 91 (11%) accepted same‐day clinic referral and underwent medical circumcision. Of 900 women offered same‐day long‐term FP referrals, 25 accepted. The CLHC cost, including census, mobilization and testing services, was $23,597 ($8.57/participant). C onclusions: Elected village leaders successfully planned and conducted a 6‐day multi‐disease health campaign with service provision by local clinic staff that reached over half of a rural Ugandan community. These data suggest it is feasible for local leaders and clinics to adopt a multi‐disease health campaign approach to scale‐up HIV testing in rural Africa.  相似文献   
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