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991.
Emerging genotype (GGIIb) of norovirus in drinking water, Sweden 总被引:2,自引:0,他引:2
Nygård K Torvén M Ancker C Knauth SB Hedlund KO Giesecke J Andersson Y Svensson L 《Emerging infectious diseases》2003,9(12):1548-1552
From May through June 2001, an outbreak of acute gastroenteritis that affected at least 200 persons occurred in a combined activity camp and conference center in Stockholm County. The source of illness was contaminated drinking water obtained from private wells. The outbreak appears to have started with sewage pipeline problems near the kitchen, which caused overflow of the sewage system and contaminated the environment. While no pathogenic bacteria were found in water or stools specimens, norovirus was detected in 8 of 11 stool specimens and 2 of 3 water samples by polymerase chain reaction. Nucleotide sequencing of amplicons from two patients and two water samples identified an emerging genotype designated GGIIb, which was circulating throughout several European countries during 2000 and 2001. This investigation documents the first waterborne outbreak of viral gastroenteritis in Sweden, where nucleotide sequencing showed a direct link between contaminated water and illness. 相似文献
992.
Lindbäck H Lindbäck J Tegnell A Janzon R Vene S Ekdahl K 《Emerging infectious diseases》2003,9(4):438-442
Dengue fever (DF) has become common in western travelers to the tropics. To improve the basis for travel advice, risk factors and dengue manifestations were assessed in 107 Swedish patients for whom DF was diagnosed after return from travel in 1998 and 1999. Patient data were compared with data on a sample of all Swedish travelers to dengue-endemic countries in the same years. Only three of the patients had received pretravel advice concerning DF from their physicians. Hemorrhagic manifestations were common (21 of 74 patients) but caused no deaths. Risk factors for a DF diagnosis were travel to the Malay Peninsula (odds ratio [OR] 4.95; confidence interval [CI] 2.92 to 8.46), age 15-29 years (OR 3.03; CI 1.87 to 4.92), and travel duration >25 days (OR 8.75; CI 4.79 to 16.06). Pretravel advice should be given to all travelers to DF-endemic areas, but young persons traveling to southern and Southeast Asia for >3 weeks (who constituted 31% of the patients in our study) may be more likely to benefit by adhering to it. 相似文献
993.
A portable nuclear medicine (NM) processing system was established in Kalgoorlie and an acute myocardial perfusion scintigraphy (MPS) service was provided for the local regional hospital. After scanning the patient, the data were processed on a laptop computer and JPEG images were transmitted to a secure Web server. A secure email message, with the URL link enclosed and a provisional indication of normal or abnormal findings, was sent to the referring clinician from the NM facility. Use of the Internet allowed for a group consultation between the NM technician, the referrer and the cardiologist in Perth. During a three-month study period, 42 patients were referred for exclusion of acute coronary syndrome. Of these, 21 (50%) demonstrated abnormal perfusion studies, two of which were classified as requiring urgent medical intervention. Seventeen studies were normal (41%) and four (10%) were designated equivocal. There was an alteration in the treatment plan for 32 patients (76%), including four for whom admission or further investigation was deemed unwarranted. The results suggest that MPS findings, distributed via the Internet, allow for earlier risk stratification and have a direct affect on clinical decision making. 相似文献
994.
995.
About 80% of pancreatic cancer patients have glucose intolerance or frank diabetes. This observation has led to the following
two hypotheses: i. pancreatic cancer causes the associated diabetes and ii. the conditions associated with diabetes promote the development of pancreatic cancer. Evidence supporting both hypotheses
has been accumulated in previous studies. This article reviews these studies, especially those that have been conducted recently. 相似文献
996.
Papadopoulou A Trangas T Teixeira MR Heim S Dimitriadis E Tsarouha H Andersen JA Evangelou E Ioannidis P Agnantis NJ Pandis N 《Neoplasia (New York, N.Y.)》2003,5(2):170-178
It has been proposed that the structural and numerical chromosome abnormalities recorded in breast cancer could be the result of telomere dysfunction and that telomerase is activated de novo to provide a survival mechanism curtailing further chromosomal aberrations. However, recent in vivo and in vitro data show that the ectopic expression of telomerase promotes tumorigenesis via a telomere length-independent mechanism. In this study, the relation between telomerase expression and the extent of chromosomal aberrations was investigated in 62 primary breast carcinomas. Telomerase activity was measured using a polymerase chain reaction-based telomeric repeat amplification protocol assay and 92% of the tumors were found to express telomerase with a relative activity ranging from 0 to 3839.6. Genetic alterations were determined by G-banding and comparative genomic hybridization analysis and 97% of the tumors exhibited chromosomal aberrations ranging from 0 to 44 (average: 10.98). In the overall series, the relationship between telomerase activity levels and genetic changes could be best described by a quadratic model, whereas in tumors with below-average genetic alteration numbers, a significant positive association was recorded between the two variables (coefficient=0.374, P=.017). The relationship between telomerase activity levels and the extent of genetic alteration may reflect the complex effect of telomerase activation upon tumor progression in breast carcinomas. 相似文献
997.
998.
It has been suggested that essential hypertension is determined by 2 separate mechanisms: a growth-promoting process in childhood and a self-perpetuating mechanism in adult life. We report a clinical study of 500 people taken from a cohort of 7086 men and women who were born in Helsinki from 1924 to 1933, and whose body size at birth was recorded. As expected, blood pressure levels were inversely related to birthweight and birth length. These associations, however, were confined to the 213 people who had previously been diagnosed as having hypertension. In them, a 1-kg increase in birthweight was associated with a 6.4-mm Hg (95% confidence interval, 1.0 to 11.9) decrease in systolic blood pressure recorded at the clinic, and with a 9.3-mm Hg (95% confidence interval, 2.1 to 16.5) decrease recorded by ambulatory measurement. We conclude that pathological processes initiated in utero become self-perpetuating in adult life and lead to hypertension. Among elderly people with established hypertension, these processes have a strong effect on blood pressure levels, because they are processes that do not respond well to treatment. 相似文献
999.
This study aimed to evaluate the use of mobility-provocation radiostereometry (RSA) in anterior cervical spine fusions and compare the results to deformation studies on the same patients and plain flexion-extension radiographs. Mobility-provocation RSA was used to evaluate anterior cervical spine fusions in 45 patients. The motions recorded at 3 and 12 months postoperatively were compared to RSA measurements of deformation of the fusion over time and to plain flexion-extension radiographs in the same patients taken 3 months postoperatively. Studies of rotations from right to left revealed ten cases with significant motion at 3 months, and three at 12 months. With motion from flexion to extension, ten cases showed significant motion at 3 months and three at 12 months. In only three cases was the mobility-provocation RSA considered to add any information on the stability of the fusions compared to that obtained with the deformation studies. In 37 patients mobility-provocation radiography in flexion-extension using conventional technique was done to evaluate the accuracy. The mean difference between angular motions recorded on plain radiographs and rotations around the transverse axis in flexion to extension recorded with RSA was 1.6° (range 0.04°–8.04°, SD 2.1°). The corresponding 95% and 99% confidence limits for the difference between the two methods were 5.8° and 7.2°. The study showed that the use of mobility-provocation RSA did not add any information over that obtained by deformation RSA studies. Conventional radiography is too inaccurate to measure inducible displacement in this patient population. 相似文献
1000.
Acute cholangitis remains a life-threatening complication of biliary obstruction, particularly in the elderly with comorbid disease or when there is a delay in diagnosis and treatment. The initial management consists of fluid resuscitation, correction of coagulopathy, and administration of broadspectrum antibiotics. The choice of antibiotics should cover both gram-negative and gram-positive organisms associated with cholangitis until the results of a blood culture are available. The timing and choice of biliary decompression varies depending on the response to antibiotic therapy, the presence of comorbid disease, and the underlying cause. Biliary sepsis resolves in most patients with conservative treatment, thus allowing time to perform more detailed noninterventional imaging (e.g., spiral computed tomography [CT], magnetic resonance cholangiopancreatography [MRCP]) to determine the underlying cause and level of biliary obstruction. Those with cholangitits who do not respond to conservative therapy will require urgent biliary decompression. In patients with choledocholithiasis, endoscopic drainage is now the treatment of choice or, if this fails, transhepatic biliary decompression is a useful alternative. Various endoscopic options are available for managing choledocholithiasis, ranging from endoscopic papillotomy (EP) and extraction of stones, to the placement of a biliary drainage system. In patients who respond to antibiotic therapy, EP with stone extraction is preferred, while in those with ongoing sepsis and multiple large stones, the placement of a stent with or without an EP is the safest option. Transhepatic biliary drainage is now reserved for failure of endoscopic drainage and for patients with suspected hilar cholangiocarcinoma or intrahepatic stones. Surgical biliary decompression is seldom required in the emergency setting, but still plays an important role in the definitive treatment of the underlying cause. 相似文献