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51.
Increased susceptibility to mucosal damage is a prominent feature of portal hypertensive gastropathy. Since the portal hypertensive gastric mucosa has extensive microvascular changes, we postulated that the increased sensitivity to mucosal damage could have an ischemic basis. We measured distribution of gastric serosal and mucosal oxygenation in a group of portal hypertensive and sham-operated rats, and then studied the effects of intragastric aspirin. In the basal state, gastric mucosa of portal hypertensive rats had significantly reduced oxygenation compared to controls (24±5 vs 45±7 mm Hg PO 2,P < 0.02), while serosal oxygenation was similar between the two groups. Intragastric aspirin produced significantly greater mucosal damage to portal hypertensive rats and mucosal oxygenation was almost one third that of sham-operated controls. Systemic arterial pressures and oxygenation were similar between the two groups. We conclude that there is impairment of gastric mucosal oxygenation and increased mucosal damage by aspirin in portal hypertensive rats compared with sham-operated controls. These results support our hypothesis that the increased sensitivity of the portal hypertensive mucosa to damage is a consequence of impaired mucosal oxygenation.This study was supported by the Veterans Administration Research Service.This work was presented, in part, at the Plenary Session of the American Association for the Study of Liver Diseases, May 1988, New Orleans, Louisiana.  相似文献   
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Background

Patients with diabetes mellitus are particularly prone to restenosis after percutaneous coronary intervention. An exploratory, nested, case-control study was undertaken to identify clinical, lesional, and procedural predictors of angiographic restenosis in these patients.

Methods

Seventy-five patients with diabetes mellitus with 86 coronary lesions were selected from a larger population of 217 patients who had undergone 6-month angiographic follow-up after a first, successful balloon angioplasty (PTCA) or stent implantation procedure. Data collection was by patient interview and review of hospital database and other medical records. All angiograms were analyzed with quantitative coronary angiography, and restenosis was defined as a ≥50% diameter reduction at the treated site. A multivariate analysis of 10 prespecified explanatory variables, derived from a literature review, was performed on a per-lesion basis.

Results

There were 45 patients (53 lesions) with restenosis and 30 patients (33 lesions) without restenosis. Univariate predictors of binary restenosis were periprocedural glycosylated hemoglobin level, vessel reference diameter, PTCA, and larger final balloon size to reference artery diameter ratio. Multiple logistic regression identified poor glycemic control (odds ratio [OR] 3.03, 95% CI 1.06-8.65, P = .038), small vessel reference diameter (OR 3.41, 95% CI 1.17-9.95, P = .025), and mode of intervention (OR 3.12, 95% CI 1.08-9.00, P = .036) as independent risk factors. Vessel reference diameter appeared to be an important effect modifier of the association between type of intervention and angiographic outcome, with stenting no longer superior to PTCA in patients with diabetes mellitus who had vessels <2.87 mm in diameter (P = .054).

Conclusion

Poor glycemic control, vessel size, and PTCA were independent predictors of restenosis in patients with diabetes mellitus. It is possible that improved periprocedural glycemic control, in addition to stenting, may reduce the restenosis rate in these patients.  相似文献   
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BackgroundSuperior orbital fissure syndrome (SOFS) is a rare constellation of findings consisting of ophthalmoplegia, ptosis, a fixed dilated pupil, forehead anesthesia, and loss of the corneal reflex. This syndrome, though rare, is most often encountered in trauma with individuals sustaining a facial fracture.Case ReportWe present a case of a young woman who was diagnosed with SOFS after a fall in her house, hitting her face on a nightstand. Treatment consisted of high-dose i.v. steroids followed by a taper with close follow-up in the Ophthalmology clinic. We provide a brief review of SOFS, including treatment considerations and follow-up.Why Should an Emergency Physician Be Aware of This?SOFS can be easily overlooked in an individual presenting to the emergency department after facial trauma with proptosis. However, a thorough examination of the eye, visual acuity, and intraocular pressure will focus the physician on SOFS rather than the need for immediate decompression via lateral canthotomy. This report describes a traumatic cause of SOFS, the pathophysiology and treatment, and summarizes existing literature.  相似文献   
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We recently reported a significant increase in the frequency of carriers of grey zone (GZ) alleles of FMR1 gene in Australian males with Parkinson's disease (PD) from Victoria and Tasmania. Here, we report data comparing an independent sample of 817 PD patients from Queensland to 1078 consecutive Australian male newborns from Victoria. We confirmed the earlier finding by observing a significant excess of GZ alleles in PD (4.8%) compared to controls (1.5%). Although both studies provided evidence in support of an association between GZ‐carrier status and increased risk for parkinsonism, the existing evidence in the literature from screening studies remains equivocal and we discuss the need for alternative approaches to resolve the issue.  相似文献   
59.
Global cerebral hypoperfusion may be involved in the aetiology of brain atrophy; however, long-term longitudinal studies on this relationship are lacking. We examined whether reduced cerebral blood flow was associated with greater progression of brain atrophy. Data of 1165 patients (61 ± 10 years) from the SMART-MR study, a prospective cohort study of patients with arterial disease, were used of whom 689 participated after 4 years and 297 again after 12 years. Attrition was substantial. Total brain volume and total cerebral blood flow were obtained from magnetic resonance imaging scans and expressed as brain parenchymal fraction (BPF) and parenchymal cerebral blood flow (pCBF). Mean decrease in BPF per year was 0.22% total intracranial volume (95% CI: –0.23 to –0.21). Mean decrease in pCBF per year was 0.24 ml/min per 100 ml brain volume (95% CI: –0.29 to –0.20). Using linear mixed models, lower pCBF at baseline was associated with a greater decrease in BPF over time (p =0.01). Lower baseline BPF, however, was not associated with a greater decrease in pCBF (p =0.43). These findings indicate that reduced cerebral blood flow is associated with greater progression of brain atrophy and provide further support for a role of cerebral blood flow in the process of neurodegeneration.  相似文献   
60.
An H5N1 highly pathogenic avian influenza virus was isolated from conjunctiva of a whooper swan with neurological signs, which was captured during the latest H5N1 HPAI outbreak in Japan. The conjunctival swab contained a larger amount of the virus in comparison with the tracheal swab. This is the first report on H5N1 virus isolation from the conjunctiva of a wild bird, and the result may suggest the conjunctival swab to be a critical sample for H5N1 HPAIV detection in waterfowl. Phylogenetic analysis of the HA gene indicated that the virus falls into H5N1 clade 2.3.2.1.  相似文献   
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