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1.
PURPOSE: To determine the radiologic characteristics of cystic dystrophy of the duodenal wall. MATERIALS AND METHODS: Ten patients with cystic dystrophy of the duodenal wall and chronic pancreatitis underwent ultrasonography (US) (n = 10), computed tomography (CT) (n = 10), endoscopic US (n = 5), and endoscopic retrograde cholangiopancreatography (ERCP) (n = 9). Cystic dystrophy of the duodenal wall was classified as either cystic or solid. The imaging findings were retrospectively analyzed and compared with findings at pancreatoduodenectomy (n = 10). RESULTS: The more frequent cystic type (n = 7) of cystic dystrophy of the duodenal wall was characterized by the presence of easily recognizable cystic lesions (diameter, more than 1 cm), located within the thickened wall of the second portion of the duodenum. The solid type (n = 3) of cystic dystrophy of the duodenal wall demonstrated fibrous thickening of the duodenal wall within which small cysts (diameter, less than 1 cm) were present. The intraduodenal cysts were usually elongated or bilobate with a thick wall. The thickening of the duodenal wall appeared as a solid layer between the duodenal lumen and the pancreas, hypoechoic at US, isoattenuating at unenhanced CT, and hypoattenuating in the early phase (after initiation of infusion of contrast material) and isoattenuating in the late phase (after completion of infusion) at contrast material-enhanced CT. Findings at retrospective analysis of CT and endoscopic US images were characteristic. CONCLUSION: Imaging modalities, notably CT and endoscopic US, helped establish the diagnosis of cystic dystrophy of the duodenal wall.  相似文献   
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There is little information on the possible value of screening children who are liable to haemoglobinopathies as part of pre-operative assessment for dental treatment under general anaesthesia. The present retrospective investigation examined, first, the number of patients having low haemoglobin levels among 1000 patients who had undergone haematological investigation prior to general anaesthesia in a dental outpatient unit, and, secondly, the subsequent clinical management of these patients. Haemoglobin levels of 10.0 g/dl or less were found in 31 children: 13 Asian, 7 Afro-Caribbean, 5 Mediterranean, 3 Arabic, 1 white Caucasian and 2 Oriental children. In addition, 17 patients had sickle-cell trait and 2 had beta-thalassaemia trait, but there was no relationship between the presence of haemoglobinopathy and low levels of haemoglobin. The planned general anaesthesia was undertaken for 22 of the 31 children who had low levels of haemoglobin and for the 19 children with haemoglobinopathy. Only 6 children ultimately did not undergo general anaesthesia, all failing to return. It is concluded that pre-anaesthetic haematological assessment of children needing minor dental surgery is rarely of any significant clinical value.  相似文献   
4.
Compact WLAN disc antennas   总被引:1,自引:0,他引:1  
A novel conical beam patch antenna design, suitable for local area network applications, uses a central cylindrical connection from the disc to ground to achieve a large reduction in resonant size. Results on efficiency, bandwidth, and pattern are reported for several prototypes.  相似文献   
5.
In a recent discovery, coaxial electrospinning was explored to encapsulate living organisms within a continuous bio‐polymeric microthread from which active biological scaffolds were fabricated (Townsend‐Nicholson and Jayasinghe, Biomacromolecules 2006, 7, 3364). The cells were demonstrated to have gone through all expected cellular activity without their viability being compromised. These biologically active threads and scaffolds have direct and tremendous applicability from regenerative to therapeutic medicine. Currently these post‐processed cells as composite threads and scaffolds are being investigated in‐depth at a cellular level to establish if the processing methodology has any affect on the cellular make‐up. We now demonstrate a competing non‐electric field driven approach for fabricating composite threads and scaffolds influenced only by a differential pressure. We refer to this novel composite thread to scaffold fabrication methodology as coaxial aerodynamically assisted bio‐threading (CAABT). Our investigations firstly, demonstrate that this technique can process handle living organisms without biologically perturbing them in anyway. Secondly the process is elucidated as possessing the ability to form composite active threads from which biologically viable scaffolds are formed. Finally our study employs florescent activated cell sorting (FACScan), a method by which the cellular dynamics and viability are quantified on control and threaded cellular samples at two prescribed time points. In parallel with FACScan, optical comparison of cellular morphology at three time points within a period of three weeks is carried out to photographically observe any changes in the post‐processed cellular phenotype. Our developmental investigations into this novel aerodynamically assisted threading methodology has unearthed a unique biomicrofabrication approach, which joins cell electrospinning in the cell threading to scaffold fabrication endeavor. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   
6.
There is currently a trend gaining acceptance that explicitly recognizes the need to set priorities for making rational decisions in health policy, respecting at the same time the underlying purpose of health care - to improve people's health. This trend in health policy is referred to as "health targets" although definitions vary considerably. Having been initiated by the World Health Organization in the late 1970s, the international policy on health targets is in the process of renewal to become Health for All in the Twenty-First Century. The new program highlights 10 global targets, from the reduction of worldwide burden of diseases to improvement of access to comprehensive, essential quality care. Countries such as the United Kingdom and Australia have adopted and implemented such programs which basically include cardiovascular, cancer, accidents, and mental health targets. For many countries, however, there are several difficulties in establishing similar programs. One of them is the unavailability of reliable data, although political factors and structure of health systems also play a key role in the creation of health targets. Overall, health targets appear to be a key element in building a strong public health policy, taking into consideration not only the cost of healthcare, but also the outcomes in improving health which is the ultimate goal of health care systems.  相似文献   
7.
Velocity Distribution in the Roughness Layer of Rough-Bed Flows   总被引:1,自引:0,他引:1  
Several models for the vertical distribution of the double-averaged (in time and in the plane parallel to the mean bed) longitudinal velocity in the flow region between roughness troughs and roughness tops are suggested. We found that the same model for velocity distribution may be applicable to a range of flow conditions and roughness types, which share some common features. The suggested models for velocity distribution in the near-bed region are: (1) Constant velocity; (2) exponential velocity distribution; and (3) linear velocity distribution. The measured velocity distributions may be approximated by a single model or by a combination of models depending on roughness geometry and flow conditions. The validity of these models for velocity distribution is supported by laboratory data.  相似文献   
8.
In order to explore the differing theoretical predictions of the cues-filtered-out perspective, SIDE model, and hyperpersonal model for online-to-offline relationships outside of the laboratory, a longitudinal survey study was conducted. Participants from a large online message board community who met up with an online acquaintance face-to-face completed surveys regarding their relationship with that individual before and after meeting their acquaintance face to face. Results indicated that the amount of communication with the online acquaintance was related to greater relation development whereas connection to the group was only related to greater individual closeness not satisfaction or predicted outcome value. In general the face-to-face meeting resulted in improved closeness, satisfaction, and predicted outcome value. An exploration for curvilinear effects as predicted by the hyperpersonal model revealed that predicted outcome value at time 1 had a curvilinear effect on closeness at time 2.  相似文献   
9.
Eight hundred-base sequencing in a microfabricated electrophoretic device   总被引:2,自引:0,他引:2  
The human genome will be sequenced using capillary array electrophoresis technology. Although currently achieving only 550 base reads per run, capillary arrays have increased the efficiency and lowered the cost of sequencing by eliminating gel plate preparation, reducing sample volumes, and offering automation and speed. However, much higher throughput and greater cost reductions are needed. The next major advancement in sequencing technology is expected from the development of arrays of microfabricated channels in a plate or "chip" format. For de novo sequencing, the practical utility of the microdevice approach has been limited by device length to a read of 500-600 bases per run. We demonstrate a significant milestone for a microfabricated device by obtaining an average read length of 800 bases in 80 min (98% accuracy) for either M13 standards or DNA sequencing samples from the Whitehead Institute Center for Genomic Research (WICGR) production line. This result is achieved in 40-cm-long channels using a new class of large-scale microfabricated devices. Both microfabrication of extended structures and achievement of long reads are essential steps toward a 384-lane very-large-scale microfluidic (VLSMF) system for ultrahigh-throughput DNA sequencing analysis, currently under construction in our laboratory.  相似文献   
10.
Carletta J  Anderson AH  McEwan R 《Ergonomics》2000,43(8):1237-1251
Collaborative teams are becoming increasingly important for industry, both within and across companies. There is a need for communication technology to support teams because many teams are non-collocated, or 'virtual'. Two automotive supply chain teams were observed while they were experimenting with multimedia conferencing in order to determine what support non-collocated teams need and the potential effects of introducing technologies on their group processes. The observations included meeting recordings and other sources that show the organizational factors affecting teams. Working in teams requires very close collaboration. Communication technology can help teams if it is used to foster close and relatively informal person-to-person interaction. Organizational constraints on how the technology is introduced favour high-technology, special-purpose installations, but teams can best be supported using relatively modest equipment with desktop access.  相似文献   
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