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11.
Ocular pulse amplitude (OPA) is defined as the difference between maximum and minimum intraocular pressure (IOP) during a cardiac cycle. Average values of OPA range from 1 to 4 mmHg. The purpose of this investigation is to determine the source of an irregular IOP waveform with elevated OPA in a 48-year-old male. Ocular pressure waveforms had an unusual shape consistent with early ventricular contraction. With a normal IOP, OPA was 9 mmHg, which is extraordinarily high. The subject was examined by a cardiologist and was determined to be in ventricular bigeminy. In addition, he had bounding carotid pulses and echocardiogram confirmed aortic insufficiency. After replacement of the aortic valve, the bigeminy resolved and the ocular pulse waveform became regular in appearance with an OPA of 1.6–2.0 mmHg. The ocular pressure waveform is a direct reflection of hemodynamics. Evaluating this waveform may provide an additional opportunity for screening subjects for cardiovascular anomalies and arrhythmias.  相似文献   
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BACKGROUND AND PURPOSE:Plaque ulceration is a marker of previous plaque rupture. We studied the association between atherosclerotic plaque composition at baseline and plaque ulceration at baseline and follow-up.MATERIALS AND METHODS:We included symptomatic patients with a carotid stenosis of <70% who underwent MDCTA and MR imaging at baseline (n = 180). MDCTA was repeated at 2 years (n = 73). We assessed the presence of ulceration using MDCTA. Baseline MR imaging was used to assess the vessel wall volume and the presence and volume of plaque components (intraplaque hemorrhage, lipid-rich necrotic core, and calcifications) and the fibrous cap status. Associations at baseline were evaluated with binary logistic regression and reported with an OR and its 95% CI. Simple statistical testing was performed in the follow-up analysis.RESULTS:At baseline, the prevalence of plaque ulceration was 27% (49/180). Increased wall volume (OR  = 12.1; 95% CI, 3.5–42.0), higher relative lipid-rich necrotic core (OR = 1.7; 95% CI, 1.3–2.2), higher relative intraplaque hemorrhage volume (OR = 1.7; 95% CI, 1.3–2.2), and a thin-or-ruptured fibrous cap (OR = 3.4; 95% CI, 1.7–6.7) were associated with the presence of ulcerations at baseline. In 8% (6/73) of the patients, a new ulcer developed. Plaques with a new ulceration at follow-up had at baseline a larger wall volume (1.04 cm3 [IQR, 0.97–1.16 cm3] versus 0.86 cm3 [IQR, 0.73–1.00 cm3]; P = .029), a larger relative lipid-rich necrotic core volume (23% [IQR, 13–31%] versus 2% [IQR, 0–14%]; P = .002), and a larger relative intraplaque hemorrhage volume (14% [IQR, 8–24%] versus 0% [IQR, 0–5%]; P < .001).CONCLUSIONS:Large atherosclerotic plaques and plaques with intraplaque hemorrhage and lipid-rich necrotic cores were associated with plaque ulcerations at baseline and follow-up.

Atherosclerosis in the carotid arteries is one of the leading causes of ischemic stroke with arterio-arterial embolism as the main mechanism.1,2 The degree of lumen stenosis and the symptomatic status of the patient are currently used for risk assessment and treatment decision-making.3,4 Patients with severe (≥70%) and moderate (50%–69%) carotid artery stenosis benefit from carotid endarterectomy; however, the number needed to treat to prevent recurrent stroke is relatively high.5 Moreover, almost half of neurologic events occur in patients with a low degree of stenosis.6,7 This finding has triggered investigations into other markers that may help to identify patients with a high risk of recurrent stroke. Much attention has been paid to markers of atherosclerosis, like plaque composition and plaque ulceration, with the aim of identifying vulnerable plaques.8 These vulnerable plaques have a high risk of rupture, which results in thrombus formation and embolization of plaque material and/or thrombus migrating into the intracranial circulation, thereby causing vascular occlusion and a subsequent ischemic stroke.2Plaque composition is predictive of future cerebrovascular events.9-12 Atherosclerotic plaque ulceration, visible as plaque-surface disruption, which is a marker of previous plaque rupture, is also correlated with recurrent symptoms and associated with a higher risk of ischemic stroke.13,14 However, the relation between vulnerable plaque components and plaque rupture is rarely investigated. Both plaque composition and ulceration can be assessed in vivo with different imaging modalities, but MR imaging is the best technique to assess plaque composition due to its superior soft-tissue contrast,15 whereas MDCTA exceeds MR imaging in the detection of plaque ulcerations due to its excellent spatial resolution with the possibility of multiplanar reconstruction.16,17Most previous studies investigated the relation between plaque ulcerations and plaque features using a cross-sectional study design. Generally, it was found that intraplaque hemorrhage (IPH), large lipid-rich necrotic core (LRNC), and thinning or ruptured fibrous cap were associated with the presence of ulcerations,18-21 while the presence of calcifications was inversely related to ulcerations.19 A prospective study in asymptomatic patients with severe carotid artery stenosis revealed that LRNC volume was a predictor of new surface disruption.22,23 The aim of the current study was to investigate, in symptomatic patients with mild-to-moderate (30%–69%) carotid artery stenosis, which plaque components at baseline are predictive of plaque rupture at follow-up.  相似文献   
14.
Multiple myeloma is a neoplasm of plasma cells that results in the overproduction of light and heavy chain monoclonal immunoglobulins. The incidence rate increases with age, particularly after 40 years, and is higher in men. To determine the clinical and laboratory characteristics and survival of diagnosed Egyptian multiple myeloma patients admitted to the Haemato-Oncology Department between 2000 and 2010. Records of all patients in whom multiple myeloma was diagnosed at the Kasr Al Aini Hospital between 2000 and 2010 were included in this retrospective study. The mean age of patients was 58.5 years (range, 27–80 years). Fifty-nine percent were males. The majority of patients (73 %) had an immunoglobulin G monoclonal band and 70 % were Kappa chain-positive. Mean overall survival was 37.5 months (range, 1–84 months). Survival analysis was statistically insignificant with respect to age, sex, International Staging System and type of treatment (p?>?0.05). Our records were largely comparable to those reported in Chinese studies but different from those noted in Western and Arabic countries.  相似文献   
15.
BACKGROUND: Colonoscopy preparation regimens are often poorly tolerated because they require use of large-volume bowel preparation solution and diet restrictions for adequate cleansing. This study evaluated the efficacy and tolerability of a split-dose polyethylene glycol-electrolyte solution plus bisacodyl and a regular diet. METHODS: A total of 187 patients (104 men, 83 women; age range 18-91 years) were randomly assigned to receive either 3 L of polyethylene glycol-electrolyte solution (n = 96; Group A) with a liquid diet on the day before colonoscopy, or 2 L of polyethylene glycol-electrolyte solution, one tablet of bisacodyl, and a minimally restricted diet on the day before colonoscopy, and then 1 L of the same solution on the day of colonoscopy (n = 91; Group B). Acceptability, adverse events, and willingness to retake the preparation were assessed by questionnaire. The quality of the preparation was graded by an endoscopist, blinded to the type of preparation, by using a previously described scale (excellent to poor). RESULTS: There were 96 patients in Group A and 91 in Group B. Colon cleansing was significantly better in Group B with regard to the overall quality of the preparation (p lt; 0.05). Compliance was significantly higher in Group B as evidenced by the lower number of patients who discontinued the preparation (4 vs. 15; p = 0.02) because of side effects such as nausea or vomiting. The degree of discomfort, adverse events, and willingness to retake the preparation were not significantly different between the groups. CONCLUSIONS: Colonic preparation with split-dose polyethylene glycol-electrolyte provided better quality colon cleansing and higher compliance, with less dietary restrictions, than preparation with whole-dose polyethylene glycol-electrolyte.  相似文献   
16.
There has been a growing demand for bone grafts for correction of bone defects in complicated fractures or tumours in the craniofacial region. Soft flexible membrane like material that could be inserted into defect by less invasive approaches; promote osteoconductivity and act as a barrier to soft tissue in growth while promoting bone formation is an attractive option for this region. Electrospinning has recently emerged as one of the most promising techniques for fabrication of extracellular matrix such as nano‐fibrous scaffolds that can serve as a template for bone formation. To overcome the limitation of cell penetration of electrospun scaffolds and improve on its osteoconductive nature, in this study, we fabricated a novel electrospun composite scaffold of polyvinyl alcohol (PVA)‐poly (ε) caprolactone (PCL)‐Hydroxyapatite based bioceramic (HAB), namely, PVA‐PCL‐HAB. The scaffold prepared by dual electrospinning of PVA and PCL with HAB overcomes reduced cell attachment associated with hydrophobic PCL by combination with a hydrophilic PVA and the HAB can contribute to enhance osteoconductivity. We characterized the physicochemical and biocompatibility properties of the new scaffold material. Our results indicate PVA‐PCL‐HAB scaffolds support attachment and growth of stromal stem cells; [human bone marrow skeletal (mesenchymal) stem cells and dental pulp stem cells]. In addition, the scaffold supported in vitro osteogenic differentiation and in vivo vascularized bone formation. Thus, PVA‐PCL‐HAB scaffold is a suitable potential material for therapeutic bone regeneration in dentistry and orthopaedics.  相似文献   
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We describe a rare case of an infant who was born with multiple congenital anomalies, including the absence of eyelids. This patient had many dysmorphic features consistent with a severe phenotype of ablepharon-macrostomia syndrome (AMS) including a fish-like appearance of the mouth, rudimentary ears, absence of body hair, thin skin, absent nipples, abdominal distension, and genital abnormalities. Upon presentation, there was severe exposure keratopathy causing large bilateral sterile ulcers culminating in corneal melting of both eyes. An amniotic membrane graft was used to attempt to maintain the corneal surface integrity. However, because of the late presentation, the corneas could not be salvaged. Extensive surgical reconstruction of both eyelids and bilateral penetrating keratoplasty was ultimately performed successfully to protect the ocular surfaces while trying to maximize the visual potential. Early amniotic membrane grafting may be done at the bedside and may help preserve the ocular in patients with severe eyelid deformities until more definitive treatment is performed.Key Words: Ablepharon, Macrostomia, Congenital eyelid anomalies, Absent hair, Absent eyelids  相似文献   
19.
20.
AIM:To develop a novel model of colitis in rats, using a combination of iodoacetamide and enteropathogenic E. coli(EPEC), and to elucidate the pathophysiologic processes implicated in the development of ulcerative colitis (UC).
METHODS: Hale Sprague-Dawley rats (/7 = 158) were inoculated intrarectally on a weekly basis with 4 different combinations: (a) 1% methylcellulose (HC), (b) 100 μL of 6% iodoacetamide (IA) in 1% HC, (c) 200 p.L containing 4×10^8 colony factor units (CFU) of EPEC, and (d) combined treatment of (IA) followed by bacteria (13) after 2 d. Thirty days post treatment, each of the four groups was divided into two subgroups; the inoculation was stopped for one subgroup and the other subgroup continued with biweekly inoculation until the end of the experiment. Colitis was evaluated by the clinical course of the disease, the macroscopic and microscopic alterations, activity of myeloperoxidase (HPO), and by TNF-α gene expression. RESULTS: Findings indicative of UC were seen in the combined treatment (IA + B) as well as the IA continued treatment groups: the animals showed slow rate of increase in body weight, diarrhea, bloody stools, high colonic ulcer score, as well as histological alterations characteristic of UC, with an extensive inflammatory reaction. During the course of the experiment, the MPO activity was consistently elevated and the TNF-α gene expression was upregulated compared to the control animals.
CONCLUSION: The experimental ulcerative colitis model used in the present study resembles, to a great extent, the human disease. It is reproducible with characteristics indicative of chronicity.  相似文献   
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