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941.
Pancreatic Pseudocysts   总被引:3,自引:0,他引:3  
Opinion statement Pseudocysts complicate acute pancreatitis in less than 5% of cases and chronic pancreatitis in 20% to 40% of cases. A pseudocyst is a localized collection of pancreatic fluid surrounded by a wall of granulation tissue and collagen. It takes 4 to 6 weeks for a fluid collection to mature and become a true pseudocyst. Unlike other cystic lesions of the pancreas from which they should be differentiated, pseudocysts lack an epithelial layer. Patients with pseudocysts present with a range of symptoms and signs. Pseudocysts are imaged using transabdominal ultrasound, CT, endoscopic ultrasound (EUS), and MRI. EUS confers an advantage over other imaging modalities in that certain EUS features are suggestive of pseudocysts over other cystic lesions. The diagnostic accuracy of EUS has improved further with the use of EUS-guided fine-needle aspiration. Therapeutic options include watchful observation or intervention. In our opinion, if acute pseudocysts are uncomplicated, asymptomatic, and do not appear to be enlarging on serial imaging, it is preferable to withhold intervention because many of these cysts resolve spontaneously. However, one needs to beware of the possibility of complications such as infection in unresolved pseudocysts. Pseudocysts associated with chronic pancreatitis are less likely to resolve spontaneously and are drained by intervention more frequently. Of the three interventional options, namely endoscopic, percutaneous, and surgical drainage, endoscopic drainage should be the treatment of choice if certain criteria are met. Preinterventional endoscopic retrograde cholangiopancreatography is mandatory to define ductal anatomy. If there is communication between the pseudocyst and the pancreatic duct, a transpapillary approach is preferred. Use of EUS should increase the number of cases in which pseudocysts can be drained endoscopically. Surgery should be reserved for cases in which there is a concern about malignancy or when there is glandular disruption.  相似文献   
942.
Coccidioidomycosis involving the lungs and the meninges occurred as the sole opportunistic infection in a patient with the acquired immunodeficiency syndrome (AIDS). Skin test reactivity to coccidioidin was present, but antibody response to coccidioidal antigens was markedly distinguished. Treatment with amphotericin B, administered intravenously for 3 1/2 months and intrathecally for 13 months, resulted in a disease-free interval of one year. Subsequently, coccidioidal peritonitis developed, which responded to treatment with amphotericin B. However, 29 months after the initial diagnosis, the patient died of complications of hepatic encephalopathy resulting from alcoholic cirrhosis. To our knowledge, this patient represents the first reported case of coccidioidal peritonitis in AIDS and involves the most prolonged survival of a patient with coccidioidomycosis and AIDS. The presence of positive skin test reactivity to coccidioidin may have been a predictor of prolonged survival in this patient.  相似文献   
943.
944.
Book reviews     
JGIM solicits reviews of new books from its readers. If you wish to review a book, please submit a letter of intent that identifies the book in question (title, author, and publisher) to Robert Aronowitz, MD, Book Review Editor,JGIM, Department of Medicine, Cooper Hospital, 3 Cooper Plaza—Suite 220, Camden, NJ 08103; telephone (609) 963-3674.  相似文献   
945.
946.
BACKGROUND: Oophorectomy reduces serum testosterone levels. We studied the efficacy and safety of transdermal testosterone in treating hypoactive sexual desire disorder in surgically menopausal women. METHODS: A 24-week, randomized, double-blind, placebo-controlled, parallel-group, multicenter trial was conducted in women (aged 24-70 years) who developed distressful low sexual desire after bilateral salpingo-oophorectomy and hysterectomy and who were receiving oral estrogen therapy. Women were randomized to receive placebo (n = 119) or testosterone patches in dosages of 150 microg/d (n = 107), 300 microg/d (n = 110), or 450 microg/d (n = 111) twice weekly for 24 weeks. Sexual desire and frequency of satisfying sexual activity were primary efficacy outcome measures. RESULTS: Of the 447 women randomized, 318 (71%) completed the trial. Compared with placebo, women receiving the 300-microg/d testosterone patch had significantly greater increases from baseline in sexual desire (67% vs 48%; P = .05) and in frequency of satisfying sexual activity (79% vs 43%; P = .049). The 150-microg/d group showed no evidence of a treatment effect. The 450-microg/d group also was not statistically different from the 300-microg/d or placebo groups. Marginally significant linear dose-response trends were observed for total satisfying sexual activity and sexual desire at 24 weeks (P = .06 and .06, respectively). Adverse events occurred with similar frequency in both groups; no serious safety concerns were observed. CONCLUSIONS: The 300-microg/d testosterone patch increased sexual desire and frequency of satisfying sexual activity and was well tolerated in women who developed hypoactive sexual desire disorder after surgical menopause.  相似文献   
947.
BACKGROUND & AIMS: Clinical studies have suggested an association between cardiovascular disease and infection with Helicobacter pylori. We examined the effect of H. pylori on platelets and the mechanism of the interaction. METHODS: Three of 5 strains of H. pylori induced platelet aggregation with a lag time of 5 +/- 2 minutes that was independent of the toxigenic genes cagA and vacA. Aggregation was inhibited completely by aspirin and a glycoprotein (GP) IIb/IIIa antagonist. Aggregation also was inhibited by monoclonal antibodies that prevented the von Willebrand factor (vWF) interaction with GPIb. vWF-coated H. pylori bound to cells transfected with GPIbalpha but not to mock transfected cells and this was inhibited by an antibody to GPIb. RESULTS: The interaction with platelets appeared to be mediated by vWF because platelet aggregation was blocked by an antibody to vWF. Moreover, a strain of H. pylori that induced platelet aggregation bound vWF to a greater extent than a nonaggregating strain. Aggregation also required IgG and could be inhibited by an antibody to the platelet IgG receptor (FcgammaRIIA). CONCLUSIONS: Some strains of H. pylori induce platelet activation mediated by H. pylori-bound vWF interacting with GPIb, and supported by IgG. These platelet-H. pylori interactions may contribute to the pathogenesis of H. pylori-associated peptic ulcer disease and to the association between H. pylori infection and cardiovascular disease, whereas local platelet effects may contribute to the pathogenesis of H. pylori-associated peptic ulcer disease.  相似文献   
948.
INTRODUCTION: Development of quality-of-life measures has been the focus of research in colorectal disorders in recent years. The assessment of quality of life for fecal incontinence should be more important than quantitative measurement of soiling. PURPOSE: This study assesses specific patient quality-of-life objectives, categorizes objectives, and correlates these objectives with continence scores. METHODS: One hundred eighteen patients entered into a randomized, controlled trial of biofeedback were assessed using the Direct Questioning of Objectives quality-of-life measure. All objectives were documented, categorized, and correlated with continence scores and analog scales. RESULTS: In patients with neuropathic fecal incontinence, the most frequent quality-of-life group concerned the ability to get out of home, to socialize outside of home, to go shopping, and not to have to worry about the location of the nearest toilet while out of home (34 percent; 123/364). At least one of these four objectives was stated by 72 percent of patients (85/118). Only 31 percent of patients (37/118) nominated an objective related to the physical act of soiling. The ability to travel (29 percent), exercise including walking (25 percent), perform home duties (19 percent), family and relationships (22 percent), and job (13 percent) were less frequently cited by patients. CONCLUSION: Continence scores focus heavily on the physical aspects of incontinence such as soiling and hygiene, aspects which seem to be less important to the patients themselves. It is important, therefore, that assessments of fecal incontinence should include reference to quality of life, and in particular to its impact on activities relating to getting out of the house.  相似文献   
949.
Role of oxidative stress in cardiac remodelling after myocardial infarction   总被引:2,自引:0,他引:2  
Recovery from myocardial infarction is associated with a series of alterations in heart structure and function, collectively known as cardiac remodelling, which play a major role in the subsequent development of heart failure. Early remodelling involves infarct scar formation in the ischaemic zone whereas subsequent ventricular remodelling affects mainly the viable non-infarcted myocardium with especially profound alterations in the extracellular matrix. There is growing evidence for a role of oxidative stress and redox signalling in the processes underlying cardiac remodelling. Reactive oxygen species are a group of highly reactive molecules which have the potential to modulate several biological processes as well as cause tissue damage and dysfunction. Their effects can be beneficial or deleterious, depending on the concentrations produced, the site of production, and the overall redox status of the cell. Reactive oxygen species can be generated by all cardiovascular cell types. Under pathophysiological conditions, major enzymatic sources appear to be mitochondria, xanthine oxidase and the non-phagocytic NADPH oxidases. In this review, we outline the mechanisms underlying the progression of early and late cardiac remodelling with particular focus on the role of oxidative stress and the potential sources of reactive oxygen species which may be involved.  相似文献   
950.

Objectives

The purpose of this study was to assess neoatherosclerosis in a registry of prospectively enrolled patients presenting with stent thrombosis using optical coherence tomography.

Background

In-stent neoatherosclerosis was recently identified as a novel disease manifestation of atherosclerosis after coronary stent implantation.

Methods

Angiography and intravascular optical coherence tomography were used to investigate etiologic factors of neoatherosclerosis in patients presenting with stent thrombosis >1 year after implantation (very late stent thrombosis [VLST]). Clinical data were collected according to a standardized protocol. Optical coherence tomographic acquisitions were analyzed in a core laboratory. Cox regression analysis was performed to identify factors associated with the formation of neoatherosclerosis and plaque rupture as a function of time.

Results

Optical coherence tomography was performed in 134 patients presenting with VLST. A total of 58 lesions in 58 patients with neoatherosclerosis were compared with 76 lesions in 76 patients without neoatherosclerosis. Baseline characteristics were similar between groups. In-stent plaque rupture was the most frequent cause (31%) in all patients presenting with VLST. In patients with neoatherosclerosis, in-stent plaque rupture was identified as the cause of VLST in 40 cases (69%), whereas uncovered stent struts (n = 22 [29%]) was the most frequent cause in patients without neoatherosclerosis. Macrophage infiltration was significantly more frequent in optical coherence tomographic frames with plaque rupture compared with those without (50.2% vs. 22.2%; p < 0.0001), whereas calcification was more often observed in frames without plaque rupture (17.2% vs. 4%; p < 0.0001). Implantation of a drug-eluting stent was significantly associated with the formation of neoatherosclerosis (p = 0.02), whereas previous myocardial infarction on index percutaneous coronary intervention was identified as a significant risk factor for plaque rupture in patients with neoatherosclerosis (p = 0.003). No significant difference was observed in thrombus composition between patients with or without neoatherosclerosis.

Conclusions

Neoatherosclerosis was frequently observed in patients with VLST. Implantation of a drug-eluting stent was significantly associated with neoatherosclerosis formation. In-stent plaque rupture was the prevailing pathological mechanism and often occurred in patients with neoatherosclerosis and previous myocardial infarction at index percutaneous coronary intervention. Increased macrophage infiltration heralded plaque vulnerability in our study and might serve as an important indicator.  相似文献   
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