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41.
To assess platelet function profiles in diabetic and nondiabetic patients on aspirin and clopidogrel therapy, two patient populations were included to investigate the 1) acute effects of a 300-mg clopidogrel loading dose (group 1, n = 52) and 2) long-term effects of clopidogrel (group 2, n = 120) on platelet function in diabetic compared with nondiabetic patients already on aspirin treatment. Patients were stratified according to the presence of type 2 diabetes. Platelet aggregation was assessed using light transmittance aggregometry (groups 1 and 2). Platelet activation (P-selectin expression and PAC-1 binding) was determined using whole-blood flow cytometry (group 2). Clopidogrel response was also assessed. In group 1, platelet aggregation was significantly increased in diabetic (n = 16) compared with nondiabetic (n = 36) patients at baseline and up to 24 h following a 300-mg loading dose (P = 0.005). In group 2, platelet aggregation and activation were increased in diabetic (n = 60) compared with nondiabetic (n = 60) subjects (P < 0.05 for all platelet function assays). Diabetic subjects had a higher number of clopidogrel nonresponders (P = 0.04). Diabetic patients have increased platelet reactivity compared with nondiabetic subjects on combined aspirin and clopidogrel treatment. Reduced sensitivity to antiplatelet drugs may contribute to the increased atherothombotic risk in diabetic patients.  相似文献   
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OBJECTIVES/HYPOTHESIS: For oral cancer patients, the presence of neck nodal metastases is the most important disease prognosticator. However, a significant proportion of clinically N0 patients harbor occult microscopic nodal metastasis. Our objective was to determine the feasibility and accuracy of sentinel node biopsy (SNB) in the staging of T2N0 oral carcinoma patients. STUDY DESIGN: Prospective analysis. METHODS: Twenty patients with previously untreated N0 oral cavity squamous cell carcinoma were studied. Each patient had an SNB performed using preoperative technetium sulfur colloid lymphoscintigraphy, intraoperative gamma probe guidance, and intraoperative peritumoral injection of 1% isosulfan blue. All patients underwent neck dissection.The sentinel lymph nodes (SLNs) were sectioned in 2- to 3-mm intervals, formalin fixed, and sectioned at three levels. The non-SLNs were sectioned in a routine manner for histologic examination. RESULTS: SLNs were identified in all patients (100%) and accurately predicted the pathologic nodal status in 18 of 20 patients (90%). Tumor was found exclusively in the SLNs in six patients (30%). Two patients had positive SLNs at multiple neck levels. Two patients had a negative SLN and a positive non-SLN (false-negative findings). Occult nodal metastases were present in 60% of the cohort. CONCLUSIONS: SNB is a technically feasible and accurate procedure for staging the neck in oral carcinoma patients. However, SNB accuracy is lower for floor of the mouth lesions. The rate of occult nodal metastases identified in this cohort is higher than previously reported in the literature. These results suggest that SNB warrants further multi-institutional studies.  相似文献   
44.
BACKGROUND: Although the epidemiology of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) has been explored in many investigations, management of this emerging infection has not been well-studied. For non-methicillin-resistant Staphylococcus aureus skin and soft tissue abscesses, incision and drainage is generally adequate therapy without the use of antibiotics, but this has not been established for CA-MRSA. METHODS: Children presenting to Children's Medical Center of Dallas for management of skin and soft tissue abscesses caused by culture-proved CA-MRSA were prospectively followed. We analyzed data from the initial evaluation and from two follow-up visits that focused on the management and outcome of CA-MRSA infection. Retrospective chart review was performed 2 to 6 months after the initial visit. RESULTS: Sixty-nine children were identified with culture-proved CA-MRSA skin and soft tissue abscess. Treatment consisted of drainage in 96% of patients and wound packing in 65%. All children were treated with antibiotics. Five patients (7%) were prescribed an antibiotic to which their CA-MRSA isolate was susceptible before culture results were known. Four patients (6%) required hospital admission on the first follow-up; none of these patients had received an antibiotic effective against CA-MRSA. A significant predictor of hospitalization was having a lesion initially >5 cm (P = 0.004). Initial ineffective antibiotic therapy was not a significant predictor of hospitalization (P = 1.0). Of the 58 patients initially given an ineffective antibiotic and managed as outpatients, an antibiotic active against CA-MRSA was given to 21 (36%) patients after results of cultures were known. No significant differences in response were observed in those who never received an effective antibiotic than in those who did. CONCLUSIONS: Incision and drainage without adjunctive antibiotic therapy was effective management of CA-MRSA skin and soft tissue abscesses with a diameter of <5 cm in immunocompetent children.  相似文献   
45.
Background: Laparoscopic Roux-en-Y gastric bypass (LRYGBP) is an effective operation for morbidly obese patients who have failed conservative weight loss treatments. It is currently indicated for patients with BMI >40 kg/m2 or >35 with significant co-morbidities. Controversy exists whether there is an upper limit to BMI beyond which this operation should not be performed. Methods: Between April 1999 and February 2001, 82 patients (19 male, 63 female) underwent LRYGBP. Average age was 43.6, and average BMI was 56 kg/m2. These patients were divided into those with BMI <60 and those with BMI ≥60 kg/m2. Results:There were 61 patients with BMI <60 and 21 patients with BMI ≥60. The groups were similar in age, gender, distribution or incidence of co-morbid conditions (diabetes, coronary artery disease, hypertension, sleep apnea, asthma) between the groups. The BMI ≥60 group had a significantly longer length of stay (6.6 days vs 5.3 days, P <0.05), and only 1 patient (BMI 85) developed an anastomotic leak and died. 2 patients in this group (BMI 62 and 73) developed small bowel obstruction requiring lysis of adhesions. 1 patient in the BMI <60 group developed a gastrojejunal stricture requiring balloon dilatation. Conclusion: While patients with a BMI ≥60 are at higher risk for postoperative complications, they are also at higher risk from continued extreme obesity. In our series, 85% of these patients had an uneventful postoperative course and began shedding excess weight. BMI ≥60 should not be a contraindication for LRYGBP.  相似文献   
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47.
Treatment of pain syndromes with venlafaxine   总被引:4,自引:0,他引:4  
Major depressive disorder (MDD) and anxiety disorders such as generalized anxiety disorder (GAD) are often accompanied by chronic painful symptoms. Examples of such symptoms are backache, headache, gastrointestinal pain, and joint pain. In addition, pain generally not associated with major depression or an anxiety disorder, such as peripheral neuropathic pain (e.g., diabetic neuropathy and postherpetic neuralgia), cancer pain, and fibromyalgia, can be challenging for primary care providers to treat. Antidepressants that block reuptake of both serotonin and norepinephrine, such as the tricyclic antidepressants (e.g., amitriptyline), have been used to treat pain syndromes in patients with or without comorbid MDD or GAD. Venlafaxine, a serotonin and norepinephrine reuptake inhibitor, has been safe and effective in animal models, healthy human volunteers, and patients for treatment of various pain syndromes. The use of venlafaxine for treatment of pain associated with MDD or GAD, neuropathic pain, headache, fibromyalgia, and postmastectomy pain syndrome is reviewed. Currently, no antidepressants, including venlafaxine, are approved for the treatment of chronic pain syndromes. Additional randomized, controlled trials are necessary to fully elucidate the role of venlafaxine in the treatment of chronic pain.  相似文献   
48.
Tumor vasculature is an attractive therapeutic target as it differs structurally from normal vasculature, and the destruction of a single vessel can lead to the death of many tumor cells. The effects of antivascular drugs are frequently short term, with regrowth beginning less than 24 hours posttreatment. This study investigated the duration of the response to the vascular targeting agent, ZD6126, of the GH3 prolactinoma, in which efficacy and dose-response have previously been demonstrated. GH3 prolactinomas were grown in the flanks of eight Wistar Furth rats. All animals were treated with 50 mg/kg ZD6126. The tumors were examined with dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) 24 hours pretreatment and posttreatment, and at a single time between 48 and 96 hours posttreatment. No evidence of recovery of perfusion was observed even at the longest (96-hour) time point. Involvement of a statistician at the project planning stage and the use of DCE-MRI, which permits noninvasive quantitation of parameters related to blood flow in intact animals, allowed this highly significant result to be obtained using only eight rats.  相似文献   
49.
BACKGROUND: Little is known about the relative advantages of video versus internet-based decision aids to facilitate shared medical decision making. This study compared internet and video patient education modalities for men considering the prostate specific antigen (PSA) test. METHODS: Two hundred and twenty-six men, aged 50 years or older, and scheduled to complete a physical examination at an HMO Health Appraisal Clinic were randomly assigned to access a website (N = 114) or view a 23-minute videotape in the clinic (N = 112) prior to deciding whether they wanted to be screened for prostate cancer. RESULTS: There were no between-groups differences in participants' ratings of convenience, effort, or satisfaction following exposure to the decision aid. Participants assigned to the video group were more likely to review the materials than individuals assigned to the internet group (98.2% vs 53.5%). Participants in the video group showed significantly greater increases in PSA knowledge and were more likely to decline the PSA test than individuals assigned to the internet group. However, participants in the internet group who reviewed the entire online presentation showed similar increases in PSA knowledge as video participants. Only 5% of all participants visited other websites to inform themselves about the PSA test. CONCLUSIONS: Overall, the video was significantly more effective than the Internet in educating participants about benefits and risks of PSA screening.  相似文献   
50.
Although more than 5% of the geriatric male population is thought to have an abdominal aortic aneurysm, no study has evaluated the ability of ED physician sonographers to screen for this condition. The purpose of this study was to evaluate whether a screening program to sonographically identify abdominal aortic aneurysms would result in increased identification of this potentially lethal disease. This prospective clinical study used a convenience sample and was performed in a community teaching hospital ED. Hemodynamically stable male patients > or = 65 years of age presenting for reasons other than back, flank, or abdominal pain were eligible. After obtaining informed consent, patients underwent bedside ultrasound of the abdominal aorta by EPs. All participating physician sonographers met SAEM credentialing recommendations for performing sonography. The maximal transverse diameter of the aorta was measured at each of three locations: proximal, mid, and distal aorta. All patients with aortic diameters > or = 3.0 cm were confirmed by formal ultrasound in the radiology department. Over a 12-month period, 103 subjects were enrolled in the study. ED physician sonographers identified eight patients with abdominal aortic diameters > or = 3.0 cm. Abdominal aortic aneurysm was confirmed in 6 of 8 subjects, yielding a positive predictive value of 75%. An EP sonographic screening program can identify abdominal aortic aneurysms in asymptomatic men older than 65 years of age.  相似文献   
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