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1.
Computed tomography and the prediction of pancreatic abscess in acute pancreatitis. 总被引:11,自引:2,他引:9
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Pancreatic abscess has become the most common cause of death from acute pancreatitis. Since computed tomography (CT) permits noninvasive imaging of the peripancreatic anatomy, the relationship of early CT findings to late pancreatic sepsis has been evaluated in 83 patients with acute pancreatitis. Pancreatic abscesses developed in 18 patients and were responsible for five of the six deaths in this study. Initial CT findings were graded: A = normal, in 12 patients; B = pancreatic enlargement alone, in 19; C = inflammation confined to pancreas and peripancreatic fat, in 17; D = one peripancreatic fluid collection, in 12; and E = two or more fluid collections, in 23. The incidence of pancreatic abscess in grades A and B was 0%; in grade C, 11.8%; in grade D, 16.7; and in grade E, 60.9%. The severity of pancreatitis was also graded by previously reported prognostic signs as "mild" (0-2 signs) in 56 patients, "moderate" (3-5 signs) in 22, and "severe" (greater than or equal to 6 signs) in five patients. The incidence of abscesses in mild disease was 12.5%; in moderate, 31.8%; and in severe, 80%. Fluid collections on CT resolved spontaneously in 19 of 35 (54.3%) patients. Abscess developed in two patients with no fluid collections on initial CT study. No abscess occurred in 31 patients with CT grades A or B, and in one of 22 patients (4.5%) with CT grade C or D and less than three positive prognostic signs. Among 30 patients with CT grade E or CT grade C or D and three or more positive prognostic signs, 17 (56.7%) developed abscesses. All deaths were in patients with five or more positive prognostic signs. Early imaging of the pancreas by CT identifies a group of patients with increased risk of pancreatic abscess. Identification of this group is improved further by use of early objective prognostic signs. 相似文献
2.
PURPOSE: To determine whether the "accordion sign" is a specific computed tomographic (CT) sign of Clostridium difficile colitis. MATERIALS AND METHODS: Fifty-seven patients with CT evidence of severe colitis, as judged by colonic wall thickening, an abnormal haustral pattern, the target sign, and stranding of the pericolic fat, were identified from a computerized CT database for 25 months. CT images were retrospectively evaluated for the presence of oral contrast material in the colon and for the accordion sign. The medical and laboratory records of all patients were reviewed and correlated with CT findings to establish the cause of colitis. RESULTS: Oral contrast material had reached the colon in 35 of 57 patients at the time of the CT examination. The images in 15 of these patients demonstrated the accordion sign, and those in 20 patients did not. C difficile colitis was documented in four of the 15 cases displaying the accordion sign. In the remaining 11 patients, a different cause was documented. Oral contrast material had not reached the colon in the remaining 22 patients. Within this group with findings similar to the accordion sign, five patients had documented C difficile colitis, and four had colitis from other causes. CONCLUSION: The accordion sign is indicative of severe colonic edema or inflammation, but it is not specific for C difficile colitis. 相似文献
3.
The diagnostic potential of CT and sonography in detecting clinically unrecognized cases of spigelian hernia is illustrated and discussed. These imaging modalities can promptly and reliably diagnose spigelian hernia based on the following findings: (1) peritoneal and muscular defect along the spigelian line in the lower abdomen; (2) intraparietal location of the hernial sac; and (3) hernial sac containing omentum and/or mesentery and loops of bowel. Two recently diagnosed cases are presented together with a short review of the literature. 相似文献
4.
Neuropsychiatric symptoms in Alzheimer's disease are related to functional connectivity alterations in the salience network
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Marcio L. F. Balthazar Fabrício R. S. Pereira Tátila M. Lopes Elvis L. da Silva Ana Carolina Coan Brunno M. Campos Niall W. Duncan Florindo Stella Georg Northoff Benito P. Damasceno Fernando Cendes 《Human brain mapping》2014,35(4):1237-1246
Neuropsychiatric syndromes are highly prevalent in Alzheimer's disease (AD), but their neurobiology is not completely understood. New methods in functional magnetic resonance imaging, such as intrinsic functional connectivity or “resting‐state” analysis, may help to clarify this issue. Using such approaches, alterations in the default‐mode and salience networks (SNs) have been described in Alzheimer's, although their relationship with specific symptoms remains unclear. We therefore carried out resting‐state functional connectivity analysis with 20 patients with mild to moderate AD, and correlated their scores on neuropsychiatric inventory syndromes (apathy, hyperactivity, affective syndrome, and psychosis) with maps of connectivity in the default mode network and SN. In addition, we compared network connectivity in these patients with that in 17 healthy elderly control subjects. All analyses were controlled for gray matter density and other potential confounds. Alzheimer's patients showed increased functional connectivity within the SN compared with controls (right anterior cingulate cortex and left medial frontal gyrus), along with reduced functional connectivity in the default‐mode network (bilateral precuneus). A correlation between increased connectivity in anterior cingulate cortex and right insula areas of the SN and hyperactivity syndrome (agitation, irritability, aberrant motor behavior, euphoria, and disinhibition) was found. These findings demonstrate an association between specific network changes in AD and particular neuropsychiatric symptom types. This underlines the potential clinical significance of resting state alterations in future diagnosis and therapy. Hum Brain Mapp 35:1237–1246, 2014. © 2013 Wiley Periodicals, Inc. 相似文献
5.
Staging of acute pancreatitis 总被引:22,自引:0,他引:22
Balthazar EJ 《Radiologic clinics of North America》2002,40(6):1199-1209
Management of patients with acute pancreatitis is based on the early assessment of severity of disease. Initial staging is established on clinical and laboratory grounds and on the findings of contrast-enhanced CT imaging. Individual clinical parameters and laboratory indices, although sometimes helpful, are not sufficiently accurate to reliable assess the severity of an acute attack. Numerical grading systems (Ranson's, APACHE II) with sensitivities of about 70% are commonly used today as indicators of systemic failure and predictors of disease severity. Helical or MDCT scanning performed during the administration of a bolus of i.v. contrast material is performed to evaluate pancreatic morphology, detect pancreatic necrosis, and depict retroperitoneal complications. CT staging and the CT severity index have proved to be a reliable indicator of disease severity, having shown an excellent correlation with the risk of death and the development of local and systemic complications in this population. 相似文献
6.
Courtship behaviors were interpreted by ethologists as being examples of 'sign stimuli' that would act as 'releasers' of stereotypic species-typical behaviors in conspecifics. A key component of the sign stimulus concept is that some form of stimulus filtering occurs that is responsible for the marked selective behavioral responsiveness. Studies of immediate early gene induction in the avian brain in response to conspecific stimuli associated with courtship and mating reveal that such gene induction is highly selective. In male Japanese quail (Coturnix japonica), studies of the immediate early gene c-fos or zenk have been conducted in birds engaging in both appetitive and consummatory aspects of male sexual behavior. High induction of immediate early genes occurs in hypothalamic and limbic areas such as the medial preoptic nucleus, bed nucleus striae terminalis and parts of the archistriatum in birds who had copulated and/or who had expressed a learned social proximity response, reflecting appetitive sexual behavior. Immediate early gene expression was also increased in telencephalic areas such as the hyperstriatum ventrale that presumably plays a role in the integration of sensory cues related to female recognition. In European starlings, studies of zenk induction have been conducted in females who hear male-typical courtship song. Clayton and Mello had shown that zenk is induced in the auditory telencephalon of canaries and zebra finches at high levels specifically in response to conspecific song. Immediate early genes such as fos and zenk are also expressed in song control nuclei specifically in association with song production. In starlings it was found that song was effective in rapidly inducing zenk expression in the auditory telencephalon in males and in females in the breeding as well as in the non-breeding season. Thus, the expression is not greater in females who use song to choose mates or during the breeding season when females are choosing mates. However, there is evidence that high levels of induction in certain areas of the auditory telencephalon in females are greater in response to songs organized in longer bouts that females prefer. Though immediate early gene induction in the brain does not exactly mimic selective behavioral responses to sign stimuli it may represent one important way in which stimulus selectivity of the sort hypothesized previously by Tinbergen and Lorenz is coded. Engaging in species-typical behaviors is also associated with motor-driven immediate early gene expression. 相似文献
7.
E J Balthazar 《Gastrointestinal radiology》1977,2(1):49-56
Defective fixation during embryologic development is responsible for a variety of segmental colonic malpositions seen during barium enema examinations. A review of the normal development process of fixation is presented, together with the most common and significant aberrations. On the right side clinical entities such as axial torsion, cecal bascule, retrocolic sigmoid, and pericolic bands are discussed and illustrated. On the left side, the configuration and clinical implications of the malposition of the splenic flexure are analyzed. It is pointed out that reversed configurations of the splenic flexure associated with failure of fixation of the entire descending colon may occur as an isolated congenital abnormality and may not necessarily be associated with renal anomalies. The characteristic radiographic appearance of the persistent descending mesocolon and its potential for complications is in addition emphasized. Familiarization with the radiographic appearance and clinical implications of these common abnormalities is essential in the daily interpretation of barium enema examinations. 相似文献
8.
Air in gallbladder: a frequent finding in gallstone ileus. 总被引:1,自引:0,他引:1
A retrospective assessment of the presence of air in the biliary tract is presented, based on plain film findings in 16 proven cases of gallstone ileus. In addition to five cases that demonstrated air in the biliary radicles, four cases exhibited air exclusively in the gallbladder and duodenal bulb. A clearly identifiable radiographic appearance composed of two adjacent small air-fluid levels in the right upper quadrant is described. This radiographic feature represents the air- and fluid-filled duodenal cap adjacent to the visualized shrunken gallbladder. Recognition of this combination of findings helps in establishing a prompt preoperative diagnosis in cases of gallstone ileus. 相似文献
9.
Watson-Jones D Changalucha J Gumodoka B Weiss H Rusizoka M Ndeki L Whitehouse A Balira R Todd J Ngeleja D Ross D Buvé A Hayes R Mabey D 《The Journal of infectious diseases》2002,186(7):940-947
To measure the impact of maternal syphilis on pregnancy outcome in the Mwanza Region of Tanzania, 380 previously unscreened pregnant women were recruited into a retrospective cohort at delivery and tested for syphilis. Stillbirth was observed in 18 (25%) of 73 women with high-titer active syphilis (i.e., women with a rapid plasma reagin titer > or = 1 :8 and a positive Treponema pallidum hemagglutination assay or indirect fluorescent treponemal antibody test result), compared with 3 (1%) of 233 uninfected women (risk ratio [RR], 18.1; P<.001). Women with high-titer active syphilis were also at the greatest risk of having low-birth-weight or preterm live births (RR, 3.0 and 6.1, respectively), compared with women with other serological stages of syphilis. Among unscreened women, 51% of stillbirths, 24% of preterm live births, and 17% of all adverse pregnancy outcomes were attributable to maternal syphilis. Syphilis continues to be a major cause of pregnancy loss and adverse pregnancy outcome among women who do not receive antenatal syphilis screening and treatment. 相似文献
10.
Watson-Jones D Gumodoka B Weiss H Changalucha J Todd J Mugeye K Buvé A Kanga Z Ndeki L Rusizoka M Ross D Marealle J Balira R Mabey D Hayes R 《The Journal of infectious diseases》2002,186(7):948-957
Treatment for maternal syphilis with single-dose benzathine penicillin (2.4 million units intramuscularly) is being implemented in many parts of sub-Saharan Africa. To examine the effectiveness of this regimen, a prospective cohort of 1688 pregnant women was recruited in Tanzania. Birth outcomes were compared among women treated for high-titer (n=133; rapid plasma reagin [RPR] titer > or = 1:8 and Treponema pallidum hemagglutination assay [TPHA]/fluorescent treponemal antibody [FTA] positive) and low-titer (n=249; RPR titer <1:8 and TPHA/FTA positive) active syphilis and 950 uninfected women. Stillbirth or low-birth-weight live births were observed in 2.3% and 6.3%, respectively, of women treated for high-titer active syphilis and in 2.5% and 9.2%, respectively, of seronegative women. There was no increased risk for adverse pregnancy outcome for women treated for high-titer active syphilis (odds ratio [OR], 0.76; 95% confidence interval [CI], 0.4-1.4) or low-titer active syphilis (OR, 0.95; 95% CI, 0.6-1.5), compared with seronegative women. Single-dose treatment is effective in preventing adverse pregnancy outcomes attributable to maternal syphilis. 相似文献