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101.
INTRODUCTION: Approximately one third of stable patients with significant intra-abdominal injury do not have significant intraperitoneal blood evident on admission. We hypothesized that a delayed, repeat ultrasound study (Secondary Ultrasound--SUS) will reveal additional intra-abdominal injuries and hemoperitoneum. METHODS: We performed a prospective observational study of trauma patients at our Level I trauma center from April 2003 to December 2003. Patients underwent an initial ultrasound (US), followed by a SUS examination within 24 hours of admission. Patients not eligible for a SUS because of early discharge, operative intervention or death were excluded. All US and SUS exams were performed and evaluated by surgical/emergency medicine house staff or surgical attendings. RESULTS: Five hundred forty-seven patients had both an initial US and a SUS examination. The sensitivity of the initial US in this patient population was 31.1% and increased to 72.1% on SUS (p < 0.001) for intra-abdominal injury or intra-abdominal fluid. The specificity for the initial US was 99.8% and 99.8% for SUS. The negative predictive value was 92.0% for the initial US and increased to 96.6% for SUS (p = 0.002). The accuracy of the initial ultrasound was 92.1% and increased to 96.7% on the SUS (p < 0.002). No patient with a negative SUS after 4 hours developed clinically significant hemoperitoneum. CONCLUSION: A secondary ultrasound of the abdomen significantly increases the sensitivity of ultrasound to detect intra-abdominal injury.  相似文献   
102.
Tailoring lactide/caprolactone co-oligomers as tissue adhesives   总被引:4,自引:0,他引:4  
Cohn D  Lando G 《Biomaterials》2004,25(27):5875-5884
This article introduces novel biocompatible tissue adhesives that do not involve any chemical or biochemical reactions, during their application in vivo. The use of these new adhesives is based exclusively on their temperature-dependent rheological properties. Since biocompatibility and biodegradability are additional crucial attributes of tissue adhesives, the polymers were tailored so that they as well as their degradation products are non-toxic. Branched oligomers consisting of a core molecule and biodegradable chains bound to it were synthesized and the relationship between their composition and their adhesive properties under in vitro conditions, was investigated. The oligomers comprised trimethylolpropane as the trifunctional central molecule, while lactoyl and caprolactone units formed the biodegradable segments. Oligomers with glass transition temperatures in the 20-25 degrees C range, were found to perform better. A strong connection was found between the length of the PLA blocks, the glass transition temperature (T(g)) of the different materials and their Adhesive Failure Strength (AFS) at 37 degrees C. The remarkable flexibilizing effect of the caprolactone units incorporated along the PLA blocks, allowed to generate longer biodegradable chains and to improve, therefore, the adhesive strength of the oligomers, while keeping their T(g) within the appropriate temperature interval. The TMP(LA(16)-CL(2)-LA(16)-CL(2)-LA(16))(3) oligomer attained especially high AFS values under in vitro conditions.  相似文献   
103.
The authors evaluated, in a community-based open-label trial, the effectiveness and safety of perindopril in 13,220 US hypertensive patients and studied how physicians adhere to hypertension treatment guidelines. Patients received perindopril 4 mg q.d. for 6 weeks. Based on physicians' perception of blood pressure response, the patient was either maintained on 4 mg or the dose was increased to 8 mg for an additional 6 weeks. From baseline to week 12, the mean sitting blood pressure significantly declined from 156.9/94.5 mm Hg to 139.2/84.0 mm Hg. Further dose titration resulted in a clinically significant reduction in blood pressure in all patients with inadequate response on 4 mg at week 6. Blood pressure control (<140/<90 mm Hg) was achieved at 12 weeks in 48.8% patients. The subpopulation analyses demonstrated that perindopril monotherapy was effective in both men and women, in patients of all ethnicities, and in patients <65 and ≤65 years of age. Perindopril was safe and well tolerated in all hypertensive subgroups including high-risk patients. Physicians were more attuned to controlling diastolic than systolic blood pressure, and their adherence to the treatment guidelines was found to be not optimal.  相似文献   
104.
To assess the dosimetric effect of using interpolated contours in planning intensity‐modulated radiation therapy (IMRT) for advanced T‐stage nasopharyngeal carcinoma. The present study focused on T3–T4 tumours where the proximity of targets to neurological organs poses a stringent test on the feasibility of such an approach. Contours of targets and organs were delineated on CT images of 2.5‐mm interval and a reference IMRT plan was generated. An investigative (INV) IMRT plan was then generated with the same planning protocol, but based on interpolated contours that replaced deleted contours on alternate slices. The reference and INV plans were compared. Regarding target coverage, all targets in the INV plans met the acceptance criteria except for the PTV in one case. Regarding organs, the mean dose to 1% volume of the brainstem and spinal cord in the INV plans were kept below their dose limits. No significant differences in the mean doses to others organs were found. Satisfactory target coverage and protection of critical organs to a degree similar to full‐scale contouring could be achieved with use of interpolated contours. The saving in manpower time for contouring is expected to significantly improve the throughput of the IMRT planning process.  相似文献   
105.
OBJECTIVE: We set out to determine the ability of positron emission tomography with fluorodeoxyglucose to detect groin lymph node metastases from vulvar cancer. METHODS: From January 2000 to August 2001, patients with squamous cell cancer of the vulva undergoing radical excision and lymphadenectomy were offered preoperative positron emission tomography. The imaging and pathologic status of each patient and groin were compared, and the sensitivity, specificity, and predictive value of positron emission tomography in predicting nodal metastasis were determined. RESULTS: Fifteen patients underwent positron emission tomography prior to exploration of 29 groins. Six patients had positive scans, suggesting metastases in 8 groins. Pathologically, 5 patients had metastases in 9 groins, with positron emission tomography demonstrating metastases in 4 of 5 patients and 6 of 9 groins with disease. On a patient-by-patients basis, positron emission tomography had a sensitivity of 80%, specificity of 90%, positive predictive value of 80%, and negative predictive value of 90% in demonstrating metastases. On a groin-by-groin basis, positron emission tomography had a sensitivity of 67%, specificity of 95%, positive predictive value of 86%, and negative predictive value of 86%. Positron emission tomography was more accurate in detecting extranodal metastases than disease confined within the groin nodes (P = 0.048). CONCLUSIONS: Positron emission tomography is relatively insensitive in predicting lymph node metastasis, and a negative study is not a reliable surrogate for a pathologically negative groin. However, the high specificity suggests that positron emission tomography is useful in planning radiation therapy and as an adjunct to lymphatic mapping and sentinel lymph node dissection.  相似文献   
106.
OBJECTIVE: The aim of this study was to determine the prevalence and types of complementary and alternative medicine (CAM) usage by women with gynecologic cancer in an outpatient midwestern university practice. METHODS: Any patient with a gynecologic cancer seen in the outpatient clinic of the gynecologic oncology division at Washington University over a 3-month period was eligible, excluding those patients with a new cancer diagnosis. Subjects completed a questionnaire anonymously. Two by two comparisons were made using the Fisher exact test and P was considered significant at P < 0.05. RESULTS: Nearly half (49.6%) of 113 respondents had used CAM since being diagnosed with cancer. Characteristics significantly associated with CAM use include annual income greater than $30,000, cancer site of origin other than the cervix, and use of CAM prior to cancer diagnosis. Users with annual incomes greater than $30,000 were significantly more likely to use CAM in the "other" category that included acupuncture, reflexology, and electromagnetic therapy. Fewer than 25% of CAM users received information regarding CAM from a physician, nurse, or practitioner of CAM. Women used CAM in hopes of achieving a wide range of potential benefits including both improved well-being and anti-cancer effects. The most common actual benefit these women perceived was an improvement in psychosocial well-being, including increased hope or optimism. CONCLUSIONS: American patients with gynecologic cancer frequently use CAM in addition to standard medical therapy. Oncologists caring for women with gynecologic cancer should initiate a dialogue about usage of CAM, discussing the potential adverse effects of CAM and the patient's therapeutic goals.  相似文献   
107.
In the present study, we evaluated delayed treatment effects of the proteasome inhibitor and anti-inflammatory agent MLN519 (initiated 10 h post-injury) to improve recovery following ischemic brain injury in rodents. Male rats were exposed to 2 h of middle cerebral artery occlusion (MCAo) and treated with MLN519 (1.0 mg/kg, i.v. @ 10, 24, and 48 h post-occlusion) or vehicle. By 2 weeks post-injury, 60% (6/10) of vehicle animals survived, which was improved (although non-significantly) to 78% (7/9) following MLN519 treatment. The percent loss of tissue in the ipsilateral brain hemisphere (at 2 weeks) was significantly reduced from 27+/-4% (vehicle) to 15+/-4% (MLN519). MLN519 treated animals also lost significantly less body weight (39%) and showed significant improvement in overall neurological function across the 2-week recovery period. However, no significant treatment effects were observed to reduce foot-fault deficits (balance beam) or improve recovery of operant performance (active avoidance test). Overall, delayed treatment with MLN519 provided significant improvement in 3 of 6 test metrics (histopathology, body weight, and neurological dysfunction) supporting improved outcome for brain-injured subjects.  相似文献   
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