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This study aimed to determine whether a weight-adjusted dose of subcutaneous enoxaparin is as effective and safe as oral acenocoumarol for the secondary prophylaxis of pulmonary embolism. Three hundred and eighty consecutive noncancer outpatients hospitalized with an episode of symptomatic pulmonary embolism selected treatment with acenocoumarol or enoxaparin at a dose of 1 mg/kg once daily after being informed of the type of administration and expected frequency of laboratory monitoring for both medicinal products. Endpoints were symptomatic recurrent thromboembolic events evaluated by standard objective testing, and a composite endpoint of recurrent venous thromboembolism, major bleeding, and death from any cause. One hundred and ninety-nine patients (52%) chose acenocoumarol therapy and 181 chose enoxaparin monotherapy. Four patients in the enoxaparin group (2.2%) and six patients in the acenocoumarol group (3%) had an objective thromboembolic recurrence (hazard ratio, 1.35; 95% confidence interval, 0.38-4.79; P = 0.64). Nine patients in the enoxaparin group (5.0%) had a hemorrhagic complication compared with 11 in the acenocoumarol group (5.5%) (P = 0.81). The hospital length of stay was shorter with enoxaparin compared with acenocoumarol (11 versus 16 days, P = 0.0001). Enoxaparin is as effective and safe as acenocoumarol in the secondary prevention of recurrent thromboembolic disease and is associated with shorter hospitalization.  相似文献   
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D-dimer has proved a useful diagnostic tool for the exclusion of deep venous thrombosis (DVT). The objective of this paper was to evaluate the diagnostic performance of a diagnostic algorithm combining clinical probability and D-dimer in outpatients receiving oral anticoagulant treatment (OAT) similar to those regularly applied to nonanticoagulated individuals. We enrolled 70 outpatients on OAT who presented with clinically suspected DVT; a standard diagnostic algorithm including clinical evaluation using the modified Wells score and a quantitative immunoturbidimetric D-dimer assay (STA Liatest D-Di; Diagnostica Stago, Asniéres sur Seine, France) was used. A 3-month follow-up period was applied for those patients in whom DVT was initially excluded. The prevalence of DVT was 18.5% (13/70); four of the diagnoses were made during the 3-month follow-up period. The sensitivity, specificity and negative predictive value of D-dimer were 69.2% (95 confidence interval, 42.4-87.3), 47.4% (95% confidence interval, 35.0-60.1) and 87.1% (95% confidence interval, 71.1-94.9), respectively. In conclusion, D-dimer is of limited value in outpatients on OAT presenting with clinically suspected DVT and should be omitted in such individuals; these patients should always undergo compression venous ultrasound, and repeat ultrasonography within 1 week might be warranted in cases with an initial negative examination.  相似文献   
65.
Laparoscopic Heller myotomy (LHM) has become the standard treatment option for achalasia. The incidence of esophageal perforation reported is about 5%–10%. Robotically assisted Heller myotomy (RAHM) is emerging as a safe alternative to LHM. Data comparing the two approaches are scant. The aim of this study was to compare RAHM with LHM in terms of efficacy and safety for treatment of achalasia. A total of 121 patients underwent surgical treatment of achalasia at three institutions. A retrospective review of prospectively collected perioperative data was performed. Patients were divided into two groups: group A (RAHM), 59 patients, and group B (LHM), 62 patients. All the operations were completed using minimally invasive techniques. There were 63 women and 58 men, with a mean age of 45 ±19 years (14–82 years). Fifty-one percent of patients in group A and 95% of patients in group B reported weight loss. Duration of symptoms was equal for both groups. Dysphagia was the main complaint in both groups (P = NS). There was no difference in preoperative endoscopic treatment in both groups (44% versus 27%, P = NS). Operative time was significantly shorter for LHM in the first half of the experience (141 ± 49 versus 122 ± 44 minutes, P < .05). However, in the last 30 cases there was no difference in operative time between the groups (P = NS). Intraoperative complications (esophageal perforation) were more frequent in group B (16% versus 0%). The incidence of postoperative heartburn did not differ by group. There were no deaths. At 18 and 22 months, 92% and 90% of patients had relief of their dysphagia. This study suggests that RAHM is safer than LHM, because it decreases the incidence of esophageal perforation to 0%, even in patients who had previous treatment. At short-term follow-up, relief of dysphagia was equally achieved in both groups. Presented at the Forty-Sixth Annual Meeting of The Society for Surgery of the Alimentary Tract, Chicago, Illinois, May 14–18, 2005 (oral presentation). This study was supported in part by a grant provided by Intuitive Surgical, Inc. and Ethicon Endo-Surgery, Inc.  相似文献   
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Purpose: Increasingly, evidence has shown that human papillomavirus (HPV) plays a role in the induction of certain carcinomas. The presence of HPV sequences in 56 previously untreated oral and pharyngolaryngeal carcinomas was examined by the polymerase chain reaction (PCR).Materials and Methods: After DNA extraction, samples underwent 40 replication cycles with specific oligonucleotide primers corresponding to sequences from the E6 open-reading frame of HPV-6b, HPV-16, and HPV-18. To determine the E6 genomic integration, positive samples were processed with specific primers for the corresponding HPV L1 genes. Genomic HPV DNA cloned into PBR 322 was used as positive control.Results: HPV E6 DNA of the 6b and 16 types was detected in 14 patients (25%). The L1 gene was not present.Conclusion: Detected HPV E6 DNA might be integrated into the cell genome in the positive cases as indicated by the absence of the L1 gene-coding for the viral capside. Histological and clinical parameters, such as tumor location, degree of differentiation, stage, recurrence, and survival rates, were unrelated to the presence of HPV.  相似文献   
68.
The protein Sex-lethal (SXL) controls pre-mRNA splicing of two genes involved in Drosophila sex determination: transformer (tra) and the Sxl gene itself. Previous in vitro results indicated that SXL antagonizes the general splicing factor U2AF65 to regulate splicing of tra. In this report, we have used transgenic flies expressing chimeric proteins between SXL and the effector domain of U2AF65 to study the mechanisms of splicing regulation by SXL in vivo. Conferring U2AF activity to SXL relieves its inhibitory activity on tra splicing but not on Sxl splicing. Therefore, antagonizing U2AF65 can explain tra splicing regulation both in vitro and in vivo, but this mechanism cannot explain splicing regulation of Sxl pre-mRNA. These results are a direct proof that Sxl, the master regulatory gene in sex determination, has multiple and separable activities in the regulation of pre-mRNA splicing.  相似文献   
69.
PURPOSE: Epidural anesthesia is believed to benefit colorectal anastomotic blood flow because of the sympathetic blockade it produces. Our purpose is to measure with tonometry the effect of epidural anesthesia on colorectal anastomotic oxygenation. PATIENTS AND METHODS: Fifteen patients operated on for rectal cancer (radical anterior resection) were monitored postoperatively using tonometers placed in the stomach (celiac trunk), transverse colon (superior mesenteric artery), and the anastomotic area during the operation. An epidural catheter was placed at L1-2, and on the first postoperative day, 8 ml of bupivacaine (0.25 percent) was administered. The anesthetic effect extended up to T-4. Intramucosal pH (pHi) at the three locations was measured before, during, and after the epidural blockade. RESULTS: Gastric and transverse colon pHi increased during the epidural blockade from 7.35±0.01 to 7.41±0.01 and from 7.34±0.02 to 7.40±0.02, respectively. The anastomotic pHi decreased from 7.3±0.02 to 7.24±0.03 under the epidural and increased up to 7.34±0.02 after withdrawal of the effect on the following day. All pHi variations were statistically significant (P<0.05, paired Student'st-test and Wilcoxon's test), because it was the comparison between gastric and transverse colon pHi with the anastomotic pHi during the epidural (P<0.05, one-way analysis of variance and Kruskal-Wallis tests). None of the patients developed anastomotic or other complications. CONCLUSIONS: Epidural anesthesia with bupivacaine causes a significant decrease in the oxygenation-perfusion state of colorectal anastomosis in comparison with the increase in other areas of the digestive tract. Further studies need to be done to see if other epidural anesthetic-analgesic protocols also worsen colorectal anastomotic blood flow.Supported in part by a grant from the Spanish Society of Digestive Diseases, Madrid, Spain. All tonometric catheters and drugs were donated by the Clinic University Hospital of Valencia, Spain.Read at the meeting of The American Society of Colon and Rectal Surgeons, Seattle, Washington, June 9 to 14, 1996.  相似文献   
70.
Cementoblastomas are benign lesions of the odontogenic ectomesenchyme that rarely occur related to the primary dentition, especially on the left side of the mandible. This study describes a case of a true cementoblastoma related to the left second primary mandibular molar in a 7-year-old child (the largest one seen in the left side of the mandible). Additionally, the radiographic and histologic findings of the lesion are described in details.  相似文献   
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