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1.
Sonoelasticity imaging of prostate cancer: in vitro results   总被引:2,自引:0,他引:2  
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Background Application of linear stapling devices for extrahepatic vascular control in liver surgery has been well-established. However, the technique for use of stapling devices in hepatic parenchymal transection is not well defined. Purpose To describe the safety and efficacy of our technique for use of vascular stapling devices in hepatic parenchymal transection during open right hepatic lobectomy is the purpose of this study. Methodology We reviewed our experience with 101 consecutive open right hepatic lobectomies performed by a single surgeon between January 2003 and July 2006, in which vascular staplers were utilized for the parenchymal transection phase. Results Of the 101 patients who underwent resection, 53 (52%) were female. The mean age was 58 years. Malignant disease was the indication for resection in the majority of patients (88%). Of those with cancer, 78% (69 of 89) had metastatic colorectal cancer, 6% (5 of 89) had metastatic neuroendocrine tumor, 4% (4 of 89) had hepatocellular carcinoma, 4% (4 of 89) had cholangiocarcinoma, and the remaining 8% were other metastatic cancers. Twelve patients (12%) underwent resection for hepatic adenoma or symptomatic benign disease (FNH or hemangioma). Forty-eight patients (48%) underwent a major ancillary procedure at the time of hepatic resection. Thirty-nine patients (39%) had a nonanatomic wedge resection of a left lobe lesion, 27 patients (27%) had one or more lesions treated with radiofrequency ablation (RFA), and 6 patients (6%) were treated with a synchronous bowel resection. The median total operative time was 336 min (range 155–620 min). A Pringle maneuver for temporary vascular inflow occlusion was utilized in all cases, with a median time of 9 min (range 4–17 min). Ten patients (10%) required blood transfusion during surgery or in the postoperative period. The maximum transfusion was 2 U of packed red blood cells (PRBC) in seven patients and 1 U of PRBC in three patients. The mean nadir postoperative hematocrit was 28.2. All patients with malignant disease had tumor-free margins at the completion of the procedure. The average hospital length of stay was 6.0 days. One patient (1%) developed a clinically significant bile leak requiring a postoperative endoscopic retrograde cholangiography (ERCP). No patient required reoperation. The 30 and 60-day postoperative survival was 100%. Conclusion These findings indicate that application of vascular stapling devices for parenchymal transection in major hepatic resection is a safe technique, with low transfusion requirements and minimal postoperative bile leak. The technique allows for rapid transection of the entire right hepatic lobe in under 10 min. Short video clips of the technique will be demonstrated. Presented at the 2007 American Hepato–Pancreato–Biliary Association, Las Vegas, Nevada, April 19–22, 2007 (oral presentation/video presentation).  相似文献   
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OBJECTIVE: Transmission of Staphylococcus aureus via air may play an important role in healthcare settings. This study investigates the impact of barrier precautions on the spread of airborne S. aureus by volunteers with experimentally induced rhinovirus infection (ie, the common cold). DESIGN: Prospective nonrandomized study. SETTING: Wake Forest University School of Medicine (Winston-Salem, NC).Participants. A convenience sample of 10 individuals with nasal S. aureus carriage selected from 593 students screened for carriage. INTERVENTION: Airborne S. aureus dispersal was studied in the 10 participants under the following clothing conditions: street clothes, surgical scrubs, surgical scrubs and a gown, and the latter plus a face mask. After a 4-day baseline period, volunteers were exposed to a rhinovirus, and their clinical course was followed for 12 days. Daily swabs of nasal specimens, pharynx specimens, and skin specimens were obtained for quantitative culture, and cold symptoms were documented. Data were analyzed by random-effects negative binomial models. RESULTS: All participants developed a common cold. Incidence rate ratios (IRRs) indicated that, compared with airborne levels of S. aureus during sessions in which street clothes were worn, airborne levels decreased by 75% when surgical scrubs were worn (P<.001), by 80% when scrubs and a surgical gown were worn (P<.001), and by 82% when scrubs, a gown, and a face mask were worn (P<.001). The addition of a mask to the surgical scrubs and gown did not reduce the airborne dispersal significantly (IRR, 0.92; P>.05). Male volunteers shed twice as much S. aureus as females (incidence rate ratio, 2.04; P=.013). The cold did not alter the efficacy of the barrier precautions. CONCLUSIONS: Scrubs reduced the spread of airborne S. aureus, independent of the presence of a rhinovirus-induced cold. Airborne dispersal of S. aureus during sessions in which participants wore surgical scrubs was not significantly different from that during sessions in which gowns and gowns plus masks were also worn.  相似文献   
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Screening for early ovarian cancer   总被引:5,自引:0,他引:5  
Taylor  KJ; Schwartz  PE 《Radiology》1994,192(1):1
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The marriage of two scourges, one old (mycobacterial disease) and one new (HIV), has presented an enormous challenge to the medical and public health communities, and has stirred renewed interest in mechanisms for immune control of mycobacterial infection. Virulence of both M. avium and M. tuberculosis appears to be inversely related to the capacity of the microorganisms to induce production of protective cytokines in infected hosts. TNF alpha and IFN gamma are central to this process, and mycobacterial polysaccharides may be their main determinant. Despite these similarities, M. tuberculosis and M. avium cause illnesses at the polar extremes of HIV disease. Tuberculosis, occurring early in the course of HIV disease, may promote HIV replication in otherwise latently infected cells via induction of cytokines. As such, the potential exists for accelerated progression to AIDS due to the mutual synergy of these pathogens.  相似文献   
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Clinical cardiac imaging is hindered by noise due to limited activity and imaging time. Use of 90° dual-detector systems with 90° gantry rotation may provide the best sensitivity/resolution for cardiac imaging, but this option is not readily available to those using a triple-detector system with detectors at 120° intervals. This study utilizes a cardiac/chest phantom to compare several triple-detector orbits, with assessment of sensitivity and resolution. A 180° rotation with reconstruction of two of the three heads was evaluated, resulting in overlapping 180° orbits; use of a starting angle of 165° for the first head placed the overlapping portion of the orbits over the LAO myocardial region, where camera-cardiac distance is most favorable. Use of this overlapping orbit yielded resolution equivalent to a conventional (single-head) 180° rotation. Sensitivity was 87%–90% of that of a 90° dual-detector system, and 16%–20% better than the common practice of using a 120° orbit with reconstruction of 1 /12 heads to achieve 180° of data. Use of 360° acquisition with reconstruction of all three heads provided the greatest sensitivity, though at the expense of some loss in image quality. Thus, for those centers performing cardiac imaging using a triple-detector system, use of overlapping 180° orbits is the preferred acquisition choice.  相似文献   
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Tumor vascular signals in renal masses: detection with Doppler US   总被引:3,自引:0,他引:3  
Ramos  IM; Taylor  KJ; Kier  R; Burns  PN; Snower  DP; Carter  D 《Radiology》1988,168(3):633-637
The vascularity of 49 renal masses (26 malignant and 23 benign lesions) was investigated with duplex Doppler ultrasound. Doppler signals obtained at the margins of renal masses were defined as "tumor signals" when the Doppler-shifted frequency of the lesion exceeded the frequency shift in the ipsilateral main renal artery. These exceeded 2.5 kHz with a 3-MHz insonating frequency. Among the 26 renal masses that subsequently proved to be malignant, tumor signals were obtained in 15 of 18 (83%) untreated renal cell carcinomas, in three of four Wilms tumors, and in two patients with metastases to the kidney, but not in the one patient with lymphoma. None of the 23 benign renal masses demonstrated tumor signals. Tumor vascularity in malignant lesions gives rise to abnormal, high-velocity, Doppler-shifted signals that can help in the differential diagnosis of renal masses.  相似文献   
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