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The initial management of bladder outflow obstruction typically related to benign prostatic hyperplasia (BPH) falls to a large extent within the remit of general practice. Referral onwards to secondary care typically arises following the failure to respond to conservative measures or when complications have supervened; the most significant of which is urinary retention. In the hospital setting, anaesthesia, constipation and immobility are the common precipitants. What follows is a practical guide to the management of these situations and provides an overview of the conservative, medical, minimally invasive and surgical treatments available.  相似文献   
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Remotely-controlled approach for stereotactic neurobiopsy.   总被引:1,自引:0,他引:1  
The objective of this study was to develop, demonstrate, and validate a remotely controlled operation scheme coupled with prospective magnetic resonance imaging (MRI)-based stereotaxy for in vivo neurosurgical applications. The novel concept of the prospective guidance scheme is to employ tomographical imaging feedback, such as MRI or CT, to facilitate prospectively the targeting process of a biopsy needle at near-real-time speed (1 image/s). Because the orientation of a biopsy needle pivoted at an entry point on the patient's skull has 2 degrees of freedom, the alignment of its trajectory to a target point can be guided by two-dimensional (2D) images whose plane is placed perpendicular to the desired trajectory. Using near-real-time 2D visual feedback during the adjustment of the alignment guide, the required trajectory alignment can be translated into a simple targeting task on a computer monitor employing a suitable graphic presentation. Also, both adjustments for the alignment and introduction of the biopsy needle were accomplished remotely with image-based feedback. The use of the method in actual MR-guided brain lesion biopsy procedures at 1.5 T showed an improved tissue yield due to the improved targeting accuracy even in the presence of brain shift. Furthermore, the postalignment trajectory can be validated immediately using near-real-time MRI scans in two orthogonal views before needle insertion. Because the final needle position is always visualized and confirmed, the consequent tissue sampling is performed with greater certainty, even in the case of a negative diagnosis. The actual targeting error was 1.53 +/- 0.17 mm from an intended target location, with the maximum distance error of 1.72 mm at a depth of 85 mm. This remotely controlled surgical approach with intraoperative MRI guidance is feasible at 1.5 T, and has allowed neurosurgeons to perform neurobiopsies comfortably and efficiently in a routine clinical MR scanner. This scheme provides a unique alternative stereotactic procedure that can take full advantage of the prospective guidance potential offered by various modern tomographic imaging systems.  相似文献   
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Background  

There is currently an unprecedented expressed need and demand for estimates of maternal mortality in developing countries. This has been stimulated in part by the creation of a Millennium Development Goal that will be judged partly on the basis of reductions in maternal mortality by 2015.  相似文献   
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Susceptibility to autoimmune insulin-dependent (type 1) diabetes mellitus is determined by a combination of environmental and genetic factors, which include variation in MHC genes on chromosome 6p21 (IDDM1) and the insulin gene on chromosome 11p15 (IDDM2). However, linkage to IDDM1 and IDDM2 cannot explain the clustering of type 1 diabetes in families, and a role for other genes is inferred. In the present report we describe linkage and association of type 1 diabetes to the CTLA-4 gene (cytotoxic T lymphocyte associated-4) on chromosome 2q33 (designated IDDM12). CTLA-4 is a strong candidate gene for T cell- mediated autoimmune disease because it encodes a T cell receptor that mediates T cell apoptosis and is a vital negative regulator of T cell activation. In addition, we provide supporting evidence that CTLA-4 is associated with susceptibility to Graves' disease, another organ- specific autoimmune disease.   相似文献   
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