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排序方式: 共有873条查询结果,搜索用时 15 毫秒
761.
Plasma levels of the chemokines monocyte chemotactic proteins-1 and -2 are elevated in human sepsis 总被引:18,自引:1,他引:17
Because of their effects on monocytes, monocyte chemotactic proteins-1 and -2 (MCP-1 and MCP-2) may participate in the pathophysiology of sepsis. We measured circulating MCP-1 and MCP-2 levels in 42 septic patients having positive local or blood cultures. MCP-1 and MCP-2 levels were elevated in 24 (57%) and 25 (59%) of 42 septic patients, respectively, compared with healthy volunteers. Both patients with gram- positive and gram-negative infections had elevated MCP-1 plasma levels (P = .0001) and P < .0001), respectively; Mann-Whitney-U test), whereas patients with gram-positive infection, but not those with gram-negative infection, had increased MCP-2 plasma levels (P= .0182). No relative differences in MCP-1 and MCP-2 plasma levels were observed between several subgroups of patients (sepsis v septic shock; survivors v nonsurvivors), although levels of MCP-1 were the highest in patients with the more severe forms of sepsis, ie, those with shock or a lethal outcome. Serial observations showed that MCP-1 and MCP-2 plasma levels remained elevated for at least 48 hours. MCP-1 correlated weakly with interleukin-8 and MCP-2, the correlations for which were most pronounced in patients with septic shock. MCP-2 correlated with interleukin-8, and surprisingly, with the complement activation product C3a; these correlations further improved when analyzing patients with septic shock or when applying gram-positive infections. Thus, our results not only show increased MCP-1 and MCP-2 levels in patients with sepsis, but also suggest that the synthesis and release of MCP-1 and MCP-2 in sepsis are differently regulated in part. 相似文献
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763.
Hyperthermic effects on DNA repair mechanisms 总被引:5,自引:0,他引:5
764.
Cholelithiasis: evaluation with CT 总被引:4,自引:0,他引:4
Barakos JA; Ralls PW; Lapin SA; Johnson MB; Radin DR; Colletti PM; Boswell WD Jr; Halls JM 《Radiology》1987,162(2):415-418
Computed tomography (CT) is often the first imaging modality used in the diagnosis of patients with suspected abdominal disease. While it is known that early generation CT scanners often detect gallstones, the detection rate of newer equipment is not widely known. Abdominal CT scans of 226 patients who had undergone ultrasonographic (US) studies of the gallbladder were reviewed in a blinded study to determine the accuracy of state-of-the-art CT scanning equipment in the detection of cholelithiasis. Of 110 patients with US or surgical evidence of cholelithiasis, gallstones were demonstrated on CT images of 87 (79.1% sensitivity). Overall accuracy was 89.8%, while specificity was 100%. On CT images stones could appear densely (48.3%) or slightly (11.5%) calcified, as an area with a rim of increased density (21.8%), as an area of soft-tissue density (14.9%), or as an area of low density (3.4%). Stone size, stone density, section incrementation, and the pericholecystic anatomy affected the detection rate. Understanding the spectrum of findings and the other factors involved can optimize success of diagnosis of cholelithiasis on the basis of CT examinations. 相似文献
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767.
Objective: To describe the importance of tension-type headache (TTH) in Santiago, Chile, by analyzing its prevalence, clinical features, and impact by age, gender, and socioeconomic status, using widely accepted international diagnostic criteria. Methods: In 1993, a representative sample of 1540 adults (older than 14) of the province of Santiago were interviewed using a standard questionnaire. A total of 1385 (89.9% response rate) subjects responded to the survey. Initially, a designated member of each household responded to the questionnaire. Subsequently, each household member with headache was asked to respond to questions about the severity, frequency, location, duration, associated symptoms, and impact in work and social activities of their most frequent headaches. TTH diagnoses were determined in accordance with the International Headache Society criteria of 1988. Results: Total prevalence was found to be 26.9% (95% CI: 24.6–29.3%); 35.2% in females (95% CI: 31.7–38.8%) and 18.1% in males (95% CI: 15.2–21.3%). The prevalence of episodic TTH was 24.3% (95% CI: 22.1–26.7%) and of chronic TTH 2.6% (95% CI: 1.8–3.6%). Overall, and by subtype, prevalence was significantly higher in females (ratio 1:9). There was no significant variation in prevalence by socioeconomic or age group except in chronic TTH, in which there was an increase with age. Conclusions: TTH is a prevalent condition in a sample of adults of Santiago, similar to that reported in previous studies using similar methodologies. Overall, TTH represents 72.3% of all recurrent headaches. 相似文献
768.
Routine helical CT of the abdomen: image quality considerations 总被引:1,自引:0,他引:1
769.
The carpal boss: an overview of radiographic evaluation 总被引:3,自引:0,他引:3
The carpal boss, an unmovable bony protuberance, is located on the dorsum of the wrist at the base of the second and third metacarpals adjacent to the capitate and trapezoid bones. This bony prominence may represent degenerative osteophyte formation and/or the presence of an os styloideum, an accessory ossification center that occurs during embryonic development. When this condition is symptomatic, patients present with complaints of pain and limitation of motion of the affected hand. The symptoms of carpal boss may result from an overlying ganglion or bursitis, an exterior tendon slipping over this bony prominence, or from osteoarthritic changes at this site. Radiographically, the view that best profiles the separate os styloideum is a lateral view utilizing 30 degrees of supination and ulnar deviation of the wrist. Once a diagnosis has been made, treatment can range from the use of nonsteroidal antiinflammatory medication and limited use of the wrist to surgical excision of the anatomic abnormality. 相似文献
770.