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121.
Childhood tuberculosis is perceived by many as a disease of the past. Experience in a children's hospital serving a deprived population suggested that tuberculosis and other mycobacterial infections were not declining in clinical practice. Fifty three tuberculous and 11 atypical mycobacterial infections were identified between 1978 and 1992. There was no decline in tuberculosis and nine of the 11 atypical infections occurred in the last five years. Altogether 40% of cases of tuberculosis were in non-Asian children; 32% had arrived in the UK or visited family overseas in the previous year; and 38% had a history of tuberculosis contact, usually a close adult relative. Nationally, the previous decline in tuberculosis in all ages has reversed. In the local health districts in London's east end, childhood tuberculosis has also stopped declining and seems to be increasing. It is regrettable that BCG vaccination has been abolished by some districts in the UK, against current recommendations. Childhood tuberculosis is still common in the practice described here, including among children who do not fall into conventionally recognised high risk groups. Inner city dwellers and junior doctors are both highly mobile populations, adding to the risk that paediatricians, particularly those in training, may encounter tuberculosis with little or no previous experience of the condition.  相似文献   
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Multisection, dual-echo magnetic resonance (MR) transaxial images of blood vessels contain both anatomic and qualitative information about flow. Even so, the images are produced as a series of two-dimensional tomographic sections from which full visualization of connected structures is difficult. A computer algorithm was developed that automatically detects flowing blood based on pixel intensity and calculated T2 and provides reconstructed views of vessels while analyzing and displaying flow characteristics. Images of abdominal vessels, aortic aneurysms, and the heart were encoded by flow and color to demonstrate depth. In addition, these data were reconstructed to derive a more accurate assessment of patency. With this technique, transaxial images can be used to analyze flow patterns, determine patent areas, and visualize all levels of vessels in a single image.  相似文献   
124.
We studied 17 hydronephrotic kidneys owing to stenosis of the pyeloureteral junction. Preoperative uptake of 99mtechnetium dimercaptosuccinic acid was compared to early postoperative unilateral creatinine clearance, measured by urine collection from the nephrostomy tube. An excellent correlation was found. Therefore, uptake of 99mtechnetium dimercaptosuccinic acid represents a reliable parameter of renal function even in the presence of severe urinary tract obstruction. However, 99mtechnetium dimercaptosuccinic acid uptake should be measured more than 24 hours after injection of the tracer.  相似文献   
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Somatostatin inhibits gastroenteropancreatic exocrine secretion and is often used after pancreaticoduodenectomy to reduce pancreatic secretion to minimize tissue damage and pancreatic stump complications. Because our earlier clinical work saw a major increase in delayed gastric emptying (DGE) with somatostatin prophylaxis after pylorus-preserving pancreaticoduodenectomy (PPPD), this small-group study was designed to confirm or disprove that observation. From August 1997 to December 2000, a total of 23 post-PPPD patients were randomized to receive somatostatin prophylaxis [somatostain (+)] (n = 11) or not [somatostatin] (−) (n = 12). The incidence of DGE, scintographic solid-phase emptying results on day 14 postoperatively, and sequential fasting plasma motilin levels were compared, as motilin levels are related to both gastric motility and somatostatin levels. The somatostatin(+) group exhibited greatly increased patient complaints of DGE: 9 of 11 (82%) versus 3 of 12 (25%) in the somatostatin(−) group. Radiologic scintography showed somatostatin prophylaxis prolonged the half-time (T1/2) of solid-phase emptying: 144.5 ± 51.4 minutes for somatostatin(+) versus 89.0 ± 59.9 minutes for somatostatin(−) (p < 0.001). Comparing pre-PPPD and post-PPPD plasma motilin levels prior to somatostatin infusion, motilin decreased 80% in reaction to the surgery. For somatostatin(−) patients, motilin levels oscillated, or “rang,” postoperatively, reaching a higher level on day 3, declined to a new record minimum on day 7, and by day 21 were 50% of the original and the slope of the recovery curve was increasing well. In somatostatin(+) patients the same ringing pattern was observed but decreased with motilin levels 30% to 70% lower than in the somatostatin(−) patients. By day 21 somatostatin(+) motilin levels were recovering but still only 20% original levels, and the slope of the recovery curve was not optimistic. On postoperative day 14 the plasma motilin levels (below approximately 6 bg/ml) correlated strongly with DGE for both groups. Despite the small sample size, the results indicated that (1) somatostatin prophylaxis significantly decreases fasting plasma motilin; (2) somatostatin prophylaxis produces lingering suppression of plasma motilin; (3) PPPD surgery itself significantly reduces fasting motilin levels with recovery to 50% normal at day 21; (4) the mechanism of somatostatin-induced DGE seems related to reduced fasting plasma motilin levels.  相似文献   
128.
Renal infection is an indication for surgical treatment of a solitary calyceal stone. It must be proved however, that the infection is localised to the kidney before deciding on operation, as this may be very difficult and produce severe complications. Bladder washout seems to be an excellent technique to differentiate the localisation of the infection.  相似文献   
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Because of their evolving nature and inherent scientific uncertainties, outbreaks of emerging infectious diseases can be associated with considerable fear in the general public or in specific communities, especially when illness and deaths are substantial. Mitigating fear and discrimination directed toward persons infected with, and affected by, infectious disease can be important in controlling transmission. Persons who are feared and stigmatized may delay seeking care and remain in the community undetected. This article outlines efforts to rapidly assess, monitor, and address fears associated with the 2003 severe acute respiratory syndrome (SARS) epidemic in the United States. Although fear, stigmatization, and discrimination were not widespread in the general public, Asian-American communities were particularly affected.  相似文献   
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