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41.
Summary About one of four patients could not be proctoscoped 20 cm or more. Psychologic factors, normal anatomic variations, or pathologic lesions prevented complete proctoscopy in 277 of 1,113 cases. Incomplete proctoscopy for other than organic reasons may be reduced by letting the patient know what to expect and by advising him that the examination can be stopped at any time that he requests.  相似文献   
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INTRODUCTION: A canine model was used to compare cryoablation and radiofrequency ablation (RFA) within the coronary sinus (CS) in the ability to create a transmural CS myocardial (Trans-CSM) lesion and risk of coronary artery stenosis. METHODS: After CS and left circumflex (LCx) coronary angiography, an intravascular ultrasound (IVUS) probe was placed in LCx in 29 dogs. An irrigated RFA catheter (8 dogs) or N(2)O cryoablation catheter (21 dogs) was inserted into the CS and positioned within 2 mm of LCx, confirmed by IVUS. RF (30-50W) was applied for 60 seconds at 10 CS sites. Cryoablation (-75 degrees C) was performed with one (n = 7) or two (n = 14) 4-minute applications. Dogs were sacrificed at 1 week (8 RFA and 13 cryoablation) or 3 months (8 cryoablation). RESULTS: During RFA, IVUS showed wall thickening and LCx narrowing in 9 of 10 sites. Angiography at 5-minute post-RFA identified LCx narrowing (25-90%) at 6 of 10 sites and 25-75% narrowing at 4 of 9 sites at 1-week post-RFA. During cryoablation, IVUS showed reversible ice ball compression of LCx, and no LCx narrowing by angiography at 5 minutes, 1 week, or 3 months. Histology showed Trans-CSM lesion at 10 of 10 RFA sites and 20 of 21 cryoablation sites. RFA produced LCx medial necrosis at 7 of 10 sites, involving 20-50%(median 32.5%) of LCx circumference with loss of intima at 5 of 7 sites. Single and twice 4-minute cryoablation produced LCx medial necrosis at 2 of 7 and 8 of 14 sites (5-40%, median 25% circumference). Intima was preserved at 1 week (13/13) with minor proliferation (without narrowing) at 2 of 8 sites at 3 months. CONCLUSIONS: Cryoablation in CS within 2 mm of LCx produces Trans-CSM lesions similar to RFA with lower risk of LCx stenosis than RFA.  相似文献   
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Bronchioloalveolar carcinoma (BAC) is an important subtype of pulmonary adenocarcinoma. It has received increasing attention in recent years, due to its increasing incidence and its rate of sensitivity to epidermal growth factor-tyrosine kinase inhibitors (EGFR-TKIs). This article reviews the epidemiology, risk factors, pathology, clinical presentation, and treatment of this disease. Special focus is paid to the emerging role of oral EGFR-TKIs in Bronchioloalveolar cell carcinoma.  相似文献   
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PURPOSE: To determine whether number of specimens obtained at stereotactic 11-gauge vacuum-assisted breast biopsy with the patient prone influences diagnostic accuracy and to determine whether this number varies depending on mammographic appearance of lesions as masses or microcalcifications. MATERIALS AND METHODS: Biopsy was prospectively performed in 100 patients (median age, 55 years; range, 31-81 years) with 100 lesions that were mammographically evident as masses (n = 50) and microcalcifications (n = 50) with standardized protocol to acquire 20 specimens per lesion in three 360 degrees probe rotations at one skin entry site. Specimens were histologically evaluated sequentially, and findings were compared with results of surgical excision or of mammographic follow-up for at least 24 months. Differences in diagnostic yield after each probe rotation and differences in diagnostic yield between masses and microcalcifications were determined with chi(2) test. RESULTS: Up to 12 specimens harvested within two 360 degrees probe rotations were necessary to yield correct diagnosis in 96% of patients with masses and 92% of patients with microcalcifications. Diagnostic yield was not improved with more than 12 specimens for masses or microcalcifications. In two (4%) of 47 patients with lesions that were eventually diagnosed as cancer, results at stereotactic biopsy indicated they were benign. Underestimation of diagnosis of lesions as atypical ductal hyperplasia and ductal carcinoma in situ occurred in two (50%) of four and two (17%) of 12 lesions, respectively. With 20 specimens harvested during three probe rotations, there was no statistically significant difference in diagnostic yield between patients with masses and those with microcalcifications (P =.68). CONCLUSION: At 11-gauge vacuum-assisted biopsy, highest diagnostic yield was achieved with 12 specimens per lesion, independent of mammographic appearance of the lesion. Even with standardized retrieval of 20 specimens per lesion, underestimation of disease still occurs.  相似文献   
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OBJECTIVE: The purpose of this retrospective study was to determine which mammographically detected lesions in need of imaging-guided biopsy could undergo prone, stereotactic biopsy. MATERIALS AND METHODS: From July 1991 through June 2001, 1687 consecutive patients (age range, 29-94 years; median age, 58 years) with 1894 lesions were referred by clinicians in a multispecialty clinic. The patients underwent stereotactic, prone, histologic biopsy of 1851 lesions (98%) and needle-localized breast biopsy of 43 lesions (2%). We performed stereotactic biopsies successively with 14-gauge automated large-core devices and 14- or 11-gauge vacuum-assisted devices. We evaluated lesions by patient, breast, lesion, and procedural variables to determine why stereotactic biopsy was not performed. RESULTS: Of 1851 lesions referred for stereotactic biopsy, biopsies were canceled in 42 lesions (2%) not considered suspicious enough to warrant biopsy. Of 1809 lesions in which stereotactic biopsy was considered to be warranted, stereotactic biopsy was canceled for technical reasons in 29 lesions (2%). Of 43 lesions referred for surgical biopsy, stereotactic biopsy was thought to be technically problematic in five (12%). Inability to accomplish a stereotactic biopsy in 34 (2%) of 1852 lesions needing a biopsy was due to proximity to the chest wall (n = 10, 29%), inadequate lesion visualization unrelated to lesion depth (n = 19, 56%), and patient factors (n = 5, 15%). CONCLUSION: Stereotactic biopsy had a technical success rate of 98% (1780/1809) and was used for histologic diagnosis in 96% (1780/1852) of mammographically detected lesions. Inadequate lesion visualization accounted for 85% (29/34) of stereotactic biopsy failures.  相似文献   
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