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Needle-localized breast biopsy: why do we fail?   总被引:10,自引:0,他引:10  
Jackman  RJ; Marzoni  FA  Jr 《Radiology》1997,204(3):677
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Kaposi's sarcoma. CT-radiographic correlation   总被引:1,自引:0,他引:1  
The role of CT in the diagnosis of intrathoracic Kaposi's sarcoma (KS) was evaluated retrospectively in 24 patients, in the absence of coexistent opportunistic infections. In all cases the diagnosis of KS was initially established by histologic evaluation of extrathoracic disease: 15 patients had verified parenchymal KS and nine patients endobronchial KS. (Chest roentgenograms were analyzed separately for each group: in 14 patients serial films were available for review. The predominant radiographic findings was the presence of nonspecific, bilateral, perihilar infiltrates in 22 of 24 cases (92 percent). Corresponding CT scans documented the presence of abnormal hilar densities characteristically extending into the adjacent pulmonary parenchyma along distinctly perivascular and peribronchial pathways. Discrete, poorly marginated nodules were identified radiographically in ten cases (42 percent); these proved to be randomly distributed throughout the parenchyma on CT. Radiographic evidence of mediastinal adenopathy was distinctly unusual, seen in only two cases (8 percent). While CT typically demonstrated shotty adenopathy, significantly enlarged nodes (greater than 1 cm) were rarely identified. We concluded that CT is more specific than routine roentgenograms for identifying pulmonary KS. While not pathognomonic, peribronchial and perivascular disease is sufficiently characteristic to obviate more invasive diagnostic procedures, especially in patients with established KS.  相似文献   
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Benzene disposition and metabolism were examined as a function of age in male C57BL/6N mice aged 3 and 18 months. Mice received a single oral dose of either 10 or 200 mg/kg 14C-benzene (approximately 25 microCi/kg). Excretion of 14C-derived benzene radioactivity (RA) was monitored in urine, feces, and as exhaled 14CO2 from 0 to 72 hr, and as exhaled unmetabolized benzene from 0 to 6 hr. At 10 mg/kg 14C-benzene, urinary elimination was the major route of excretion in both 3- and 18-month mice. Urinary excretion of 14C-derived benzene RA was significantly decreased in 18- vs. 3-month mice at 4, 6, 24, and 48 hr, while fecal excretion was significantly increased at 72 hr. Elimination of 14C-benzene as 14CO2 and unmetabolized 14C-benzene was also increased in 18- vs. 3-month mice at this dose. Hydroquinone glucuronide (HQG), phenylsulfate (PS), and muconic acid (MUC) were the major urinary metabolites at 10 mg/kg 14C-benzene in both 3- and 18-month mice, representing approximately 40, 28, and 15% of an administered dose of 14C-benzene. Smaller amounts of phenyl glucuronide (4.0%), pre-phenyl mercapturic acid (1.2%), and catechol glucuronide (0.5%) were also detected. No significant differences were found with age in the percentage of an administered dose of benzene excreted as the various metabolites at 10 mg/kg. At 200 mg/kg 14C-benzene, the total percentage of 14C-derived benzene RA eliminated in urine within 72 hr was not significantly different with age, but elimination at early time points (4, 6, and 8 hr) was significantly decreased in 18- vs. 3-month mice.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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荧光原位杂交技术分析人结肠菌群方法研究   总被引:2,自引:0,他引:2  
建立荧光原位杂交技术分析人体内结肠菌群的方法。取受试者新鲜粪便 ,选用 5种特异性的 16SrRNA寡核苷酸探针 ,检测粪便样本收集后的保存时间、温度 ,离心条件及样本固定液存放时间对杂交计数结果的影响。结果建立最佳实验条件为 :粪便样本收集后应尽快在 4℃下保存 ,放置时间不要超过 12小时即作处理 ;样本的适宜离心条件为 70 0g 2分钟 ;样本用多聚甲醛固定后在 - 80℃下存放时间不要超过 5个月。该方法具有较好的稳定性 ,可以有效地检出个体之间结肠菌群的差异。  相似文献   
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Acute appendicitis: CT and US correlation in 100 patients   总被引:19,自引:1,他引:18  
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Early experience with laparoscopic abdominoperineal resection   总被引:4,自引:0,他引:4  
Background: Laparoscopic abdominoperineal resection (LAPR) has not been fully evaluated as a technique in the treatment of rectal and anal cancer or inflammatory bowel disease. The purpose of our study was to evaluate the early experience with laparoscopic abdominoperineal resection at Washington University Medical Center. Methods: A prospective analysis was performed on the first 21 patients undergoing the procedure at Washington University Medical Center. Indications for surgery included rectal cancer (14 patients), anal squamous cell cancer (four patients), inflammatory bowel disease (two patients), and anal melanoma (one patient). Results: The procedure was converted to open procedure in four patients (19%). The mean (±SEM) operative time and blood loss for completed and converted LAPR were 239 ± 11 min and 424 ± 43 ml, respectively. Postoperative hematocrit dropped a mean of 8.3% ± 1.2% SEM; five patients required blood transfusion (24%). Wound complication occurred in four patients (19%; three perineal, one trocar site). Bowel function returned after a mean of 3 days, and mean postoperative hospital stay for the completed LAPR group was 5 days. Mild pain was experienced by 81% of patients (17/21) while 19% (4/21) noted moderate pain, usually of the perineal wound. The mean duration of patient-controlled analgesia use was 2 days. During the 1–44-month follow-up, six patients (29%) died from cancer (stage III or IV at operation) and only one patient developed local recurrence in the pelvis (5%). There were no trocar-site implants of cancer. Furthermore, there was no relationship between prior abdominal operations, the amount of blood loss, postoperative drop of hematocrit, or blood transfusion requirement and the length of hospitalization or complication rates. Conclusion: Laparoscopic abdominoperineal resection is a feasible alternative to the conventional open technique in both cancer and colitis patients. Received: 23 April 1996/Accepted: 8 July 1996  相似文献   
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