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排序方式: 共有666条查询结果,搜索用时 15 毫秒
1.
Amir Kimia MD John S. Brownstein PhD Karen L. Olson PhD Victor Zak PhD Florence T. Bourgeois MD MPH Kenneth D. Mandl MD MPH 《Academic emergency medicine》2006,13(7):767-773
Background: The Centers for Disease Control and Prevention is incorporating laboratory data into real-time surveillance systems. When normal patterns of laboratory test orders and results are modeled, aberrations can be detected. Because many test orders are available electronically well before results, atypical patterns of test ordering may signal outbreaks.
Objectives: The authors sought to characterize baseline patterns in the ordering and early results of lumbar punctures, motivated by the possibility of using these data for real-time surveillance for early detection of meningitis or encephalitis outbreaks.
Methods: Retrospective cohorts of pediatric emergency department patients at a single hospital (1993–2003) and from the National Hospital and Ambulatory Medical Care Survey (1992–2000) were used for analysis.
Results: Test ordering exhibits seasonal patterns, with monthly peaks in January and August (p < 0.0001). For the hospital cohort, the rate of cerebrospinal fluid pleocytosis exhibits seasonal patterns (p < 0.0001), with a peak from August to October. This is strongly associated with the rate and pattern of clinical neurologic disease (p < 0.0001). A long-term secular decline in daily test ordering is evident, dropping from 5.3 to 2.9 in the hospital sample, and from 371.8 to 185.3 in the national sample (p < 0.001). The long-term rate of pleocytosis has declined (p < 0.0001), though the yield of testing for pleocytosis has improved (p = 0.0104).
Conclusions: Laboratory test patterns correspond with those of clinical disease and are a promising source of surveillance data. Using such data for real-time monitoring requires specific adjustments for patient age, periodicities, and secular trends. 相似文献
Objectives: The authors sought to characterize baseline patterns in the ordering and early results of lumbar punctures, motivated by the possibility of using these data for real-time surveillance for early detection of meningitis or encephalitis outbreaks.
Methods: Retrospective cohorts of pediatric emergency department patients at a single hospital (1993–2003) and from the National Hospital and Ambulatory Medical Care Survey (1992–2000) were used for analysis.
Results: Test ordering exhibits seasonal patterns, with monthly peaks in January and August (p < 0.0001). For the hospital cohort, the rate of cerebrospinal fluid pleocytosis exhibits seasonal patterns (p < 0.0001), with a peak from August to October. This is strongly associated with the rate and pattern of clinical neurologic disease (p < 0.0001). A long-term secular decline in daily test ordering is evident, dropping from 5.3 to 2.9 in the hospital sample, and from 371.8 to 185.3 in the national sample (p < 0.001). The long-term rate of pleocytosis has declined (p < 0.0001), though the yield of testing for pleocytosis has improved (p = 0.0104).
Conclusions: Laboratory test patterns correspond with those of clinical disease and are a promising source of surveillance data. Using such data for real-time monitoring requires specific adjustments for patient age, periodicities, and secular trends. 相似文献
2.
Csala Léránt Bánhegyi Kardon Puskás Mucha Machovich Falus & Mandl 《Scandinavian journal of immunology》1998,48(3):269-271
Bacterial endotoxin (LPS) and fibrinogen degradation product D (FDP-D) are both potent stimulators of interleukin-6 (IL-6) production in liver, however, there are differences in their metabolic effects. The aim of the present study was to compare the role of prostaglandins in the enhancement of IL-6 production by LPS or FDP-D in perfused mouse livers. Indomethacin inhibited the effect of LPS significantly but was ineffective in the case of FDP-D. Accordingly, production of prostaglandins D2 and E2 was not elevated following the addition of FDP-D, while their formation was increased several fold by LPS. At the same time interleukin-1 (IL-1) production in perfused liver rose markedly upon the addition of FDP-D. It is suggested that prostaglandins are not involved in the effects of FDP-D on the liver. The stimulatory effect of FDP-P on IL-6 production might be the consequence of elevated IL-1 levels. 相似文献
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Image-directed percutaneous biopsies with a biopsy gun 总被引:3,自引:0,他引:3
Core tissue for histologic study is believed by many pathologists to be more diagnostic than material from needle aspiration. Recently, a biopsy "gun" has been introduced, which simplifies core biopsies. With this device, 182 biopsies of multiple anatomic sites were performed with ultrasonic, computed tomographic, and fluoroscopic guidance and 18-gauge needles. High-quality histopathologic specimens were obtained in 177 of the biopsies, and diagnostic target tissue was obtained in 167. Only three significant complications occurred: one bleeding complication that required transfusion and two cases of pneumothorax that necessitated placement of chest tubes. The biopsy gun eliminated the disjointed movements of conventional "skinny" needle biopsies, and none of the samples demonstrated significant "crush" artifact or obscuring blood, problems that are commonly associated with manual biopsy techniques. Patient discomfort was decreased with this system compared with that of manual biopsies, and the total procedure time was reduced. Because of these distinct advantages, the authors now use the biopsy gun exclusively for all percutaneous biopsies and recommend that other institutions consider the use of this biopsy method. 相似文献
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Genome sequence of tick-borne encephalitis virus (Western subtype) and comparative analysis of nonstructural proteins with other flaviviruses 总被引:13,自引:0,他引:13
The genome sequence of tick-borne encephalitis (TBE) virus (Western subtype vaccine strain Neudoerfl) was determined. This extends the previously published sequence of the structural proteins to the nonstructural protein region and noncoding sequences at the 5'- and 3'-termini. The amino-termini of the individual proteins were assigned by comparison with other flavivirus sequences. Amino acid homology calculations between TBE virus and mosquito-borne flaviviruses were performed for all nonstructural proteins. An evolutionary tree based on protein NS1 is presented that reveals the molecular basis of relationships among flaviviruses. Tick-borne and mosquito-borne flaviviruses share a common hydrophilicity profile and also other features of their primary sequences, such as the presumably functional Gly-Asp-Asp sequence element within protein NS5. Other characteristics, such as the potential N-glycosylation sites of protein NS1 and a potential proteolytic cleavage site within protein NS4B, are conserved within the mosquito-borne group, but differ in the TBE virus sequence. 相似文献
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Osteosarcomatosis 总被引:10,自引:0,他引:10
Hopper KD; Moser RP Jr; Haseman DB; Sweet DE; Madewell JE; Kransdorf MJ 《Radiology》1990,175(1):233-239
A review of the 690 cases of osteosarcoma in the radiographic file of the Armed Forces Institute of Pathology revealed 29 cases of "osteosarcomatosis" (multiple skeletal sites of osteosarcoma). Fifteen of these patients were 18 years old and under and manifested rapidly appearing, usually symmetric, sclerotic metaphyseal lesions. The remaining 14 patients were more than 18 years old and had fewer, asymmetric sclerotic lesions. In most patients (28 of 29), a radiographically dominant skeletal tumor was seen. Pulmonary metastases occurred in the majority of patients and were detected at the same time as the bone lesions. These 29 patients were studied with regard to demographic data and skeletal distribution and radiographic appearance of their lesions. As a result of the findings, a metastatic origin from a primary dominant osteosarcoma is favored over a multifocal origin as the basis for osteosarcomatosis. Osteosarcomatosis is more commonly encountered in the mature skeleton than has been previously recognized. 相似文献