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61.
This special issue addresses access to and service delivery of assistive technology (AT) in resource-limited environments (RLEs). Access to AT is complicated not simply by limited funds to purchase AT, but by larger ecosystem weaknesses in RLEs related to legislation and policy, supply, distribution, human resources, consumer demand and accessible design. We present eight diverse articles that address various aspects of the AT ecosystem. These articles represent a wide range of AT, many different countries and different research methods. Our goal is to highlight a topic that has received scant research investigation and limited investment in international development efforts, and offer an insight into how different countries and programs are promoting access to AT. We encourage researchers, funders and non-profit organizations to invest additional effort and resources in this area.  相似文献   
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Carcinoma cuniculatum (CC), a rare, well-differentiated variant of squamous cell carcinoma, is uncommon in head and neck sites but when it does occur is most common in the oral cavity. Here we report a rare case of CC involving the larynx. A 49-year-old man presented with 10 months of worsening hoarseness and, despite multiple biopsies, no diagnosis of malignancy could be established. Eventual partial excision of the lesion and histologic review of prior specimens confirmed the diagnosis of CC. Focally, a transition to respiratory epithelium indicated the presence of an associated saccular cyst. Total laryngectomy was performed and 6 months later the patient is free of disease. Only two prior cases of CC have been reported in the larynx. Diagnosis of CC is challenging given the low grade histologic features and awareness of this entity for both treating physicians and the pathologist is important to reach a diagnosis of malignancy. This case highlights the challenges in diagnosis of CC, especially in unusual locations and when associated with other lesions such as a saccular cyst. Awareness of this rare tumor type combined with close communication between treating clinicians, radiologists and pathologists should allow earlier diagnosis and treatment.  相似文献   
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Radiotherapy may result in endocrine abnormalities, osteoporosis, obesity and neurological sequelae in patients treated for cancer. In the hypothalamo-pituitary area, GH deficiency is the most frequent complication. The frequency, delay of appearance and severity of GH deficiency depend most on the dose delivered during cranial irradiation but variables as age at treatment and fractionation schedule may play an important role as well. Other hypothalamo-pituitary dysfunctions are also dose-dependent. Low dose cranial irradiation may induce precocious or early puberty, while high doses are related to gonadotropin deficiency. Endocrine complications due to extracranial irradiation such as gonadal or thyroid abnormalities are described. In spite of normal GH secretion, linear growth may be impaired by bone lesions secondary to craniospinal or total body irradiation. Results on final height have been optimized by better indicators of GH therapy associated with adequate treatment of early or precocious puberty. The purpose of this review is to explore the late endocrine sequelae of radiotherapy.  相似文献   
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Severe alpha(1)-antitrypsin (AAT) deficiency is an inherited disorder that leads to the development of emphysema in smokers at a relatively young age; most are disabled in their forties. Emphysema is caused by the protease-antiprotease imbalance when smoking-induced release of neutrophil elastase in the lung is inadequately inhibited by the deficient levels of AAT, the major inhibitor of neutrophil elastase. This protease-antiprotease imbalance leads to proteolytic damage to lung connective tissue (primarily elastic fibers), and the development of panacinar emphysema. AAT replacement therapy, most often applied by weekly intravenous infusions of AAT purified from human plasma, has been used to partially correct the biochemical defect and raise the serum AAT level above a theoretically protective threshold level of 0.8 g/L. A randomized controlled clinical trial was not considered feasible when purified antitrypsin was released for clinical use. However, AAT replacement therapy has not yet been proven to be clinically effective in reducing the progression of disease in AAT-deficient patients. There was a suggestion of a slower progression of emphysema by computed tomography (CT) scan in a small randomized trial. Two nonrandomized studies comparing AAT-deficient patients already receiving replacement therapy with those not receiving it, and a retrospective study evaluating a decline in FEV(1) before and after replacement therapy, suggested a possible benefit for selected patients. Because of the lack of definitive proof of the clinical effectiveness of AAT replacement therapy and its cost, we recommend reserving AAT replacement therapy for deficient patients with impaired FEV(1) (35-65% of predicted value), who have quit smoking and are on optimal medical therapy but continue to show a rapid decline in FEV(1) after a period of observation of at least 18 months. A randomized placebo-controlled trial using CT scan as the primary outcome measure is required. Screening for AAT deficiency is recommended in patients with chronic irreversible airflow obstruction with atypical features such as early onset of disease or disability in their forties or fifties, or positive family history, and in immediate family members of patients with AAT deficiency.  相似文献   
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The expanding indications for angioplasty coupled with the successful short and mid-term results of randomized controlled trials of drug-eluting stents have already had an unquestionable impact on the practice of coronary revascularization operations. However, coronary artery bypass grafting remains a major mode of therapy for coronary artery disease. It is likely that surgery will continue to be preferred for more complex subsets and that surgeons will have to continue to maintain good results in patients with more complex problems. Concerns regarding morbidity associated with conventional surgical myocardial revascularization on cardiopulmonary bypass have led to a resurgence of interest in off-pump bypass surgery during the last decade, with the expectation that it would be safer if cardiopulmonary bypass could be avoided. This review summarizes the impact of off-pump bypass surgery in reducing the morbidity and mortality associated with conventional coronary artery bypass on cardiopulmonary bypass by evaluating the current best-available evidence from randomized controlled trials and meta-analyses comparing off-pump surgery with conventional bypass grafting.  相似文献   
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Introduction

Vascular malformations have devastating cosmetic effects in addition to being associated with pain and bleeding. Sclerotherapy has been used as an effective therapeutic modality for the management of vascular malformations. The purpose of this case series is to describe our clinical experience of using sodium tetradecyl sulphate (STS) 3 % in the treatment of venous malformation lesions of head and neck.

Materials and Methods

Thirteen patients were included in this study (three male and ten female; age range between 8 months and 54 years; mean age 18.2 years, ±SD 15.71). The patients were treated by 3 % STS intralesional injections. Of the thirteen patients treated, complete resolution occurred in four patients (28.57 %), a good response occurred in five patients (35.7 %), a moderate response in two patients (14.28 %), a mild response in two patients (14.28 %) and no response in one patient (7.14 %). The side effects encountered in all patients were pain and edema after injection which was controlled by oral analgesics and an intramuscular injection of dexamethasone. In addition, two patients developed a superficial ulceration (11.76 %) which healed uneventfully, and one patient developed ecchymosis after injection (5.88 %).

Conclusion

Sclerotherapy with 3 % STS is a simple, safe, and effective modality for the treatment of venous malformations.  相似文献   
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