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71.
Uncommon high-risk lesions of the breast diagnosed at stereotactic core-needle biopsy: clinical importance 总被引:16,自引:0,他引:16
PURPOSE: To assess the outcome of papillary lesions, radial scars, or lobular carcinoma in situ (LCIS) diagnosed at stereotactic core-needle biopsy (SCNB). MATERIALS AND METHODS: Retrospective review of 1,236 lesions sampled with SCNB yielded 22 papillary lesions, nine radial scars, and five LCIS lesions. Diffuse lesions such as papillomatosis, papillary ductal hyperplasia, papillary ductal carcinoma in situ (DCIS), and atypical lobular hyperplasia were not included. The mammographic findings, associated histologic features, and outcome were assessed for each case. RESULTS: Sixteen papillary lesions were diagnosed as benign at SCNB. Of these, five were benign at excision, and 10 were unremarkable at mammographic follow-up. At excision of an unusual lesion containing a microscopic papillary lesion, DCIS was found. Three of four papillary lesions suspicious at SCNB proved to be papillary carcinomas; the fourth had no residual carcinoma at excision. Eight of nine radial scars were excised, which revealed atypical hyperplasia in four scars but no malignancies. One LCIS lesion was found at excision to contain DCIS. CONCLUSION: Benign or malignant papillary lesions were accurately diagnosed with SCNB in the majority of cases. Cases diagnosed as suspicious for malignancy or with atypia or unusual associated histologic findings should be excised. No malignancies were found at excision of radial scars diagnosed at SCNB. Surgical removal of these lesions following SCNB may not be routinely necessary. DCIS was found in one lesion diagnosed as LCIS at SCNB, which suggests that removal of these lesions may be prudent. 相似文献
72.
Silberman S Shaheen J Merin O Fink D Shapira N Liviatan-Strauss N Bitran D 《The Annals of thoracic surgery》2001,72(4):1217-1221
BACKGROUND: Nonstented bioprostheses have been associated with lower resting gradients than stented bioprostheses or mechanical valves. We compared the hemodynamic performance of nonstented bioprostheses and mechanical valves with normal native aortic valves at rest and exercise. METHODS: Dobutamine echocardiography was used to assess gradients and effective orifice area index at rest and exercise in patients with the Toronto stentless porcine valve (TSPV; n = 13; mean implant size 25.7 mm), Medtronic Freestyle (FR; n = 11; mean implant size 23.9 mm), Sorin Bicarbon (SOR; n = 11; mean implant size 24.5 mm), St. Jude Medical (SJM; n = 10; mean implant size 21.3 mm), and normal native aortic valves (NOR; n = 10). RESULTS: All groups demonstrated a major rise in cardiac output at maximal dobutamine infusion. At rest and exercise, respectively, mean gradients were 5.48 +/- 1.1 mm Hg and 5.83 +/- 0.9 mm Hg for TSPV, 5.68 +/- 1.2 mm Hg and 7.50 +/- 1.7 mm Hg for FR, 10.29 +/- 1.4 mm Hg and 20.78 +/- 2.7 mm Hg for SJM, 5.26 +/- 0.8 mm Hg and 11.1 +/- 1.8 mm Hg for SOR, and 1.54 +/- 0.4 mm Hg and 2.18 +/- 0.7 mm Hg for NOR. In comparison with normal valves, both stentless groups showed no change in mean gradient at exercise, whereas both mechanical groups showed an increase in gradient at exercise (p < 0.04). CONCLUSIONS: Stentless valves behave similarly to normal aortic valves in that there is almost no increase in gradient at exercise. Both mechanical valve groups showed increased gradients at exercise, suggesting that these valves obstruct blood flow. Our data add further evidence that stentless valves are hemodynamically superior to mechanical valves in the aortic position. 相似文献
73.
Sanjay Gupta M.D. Christopher D. Prevel M.D. Kenneth Shaheen M.D. Edwin Wilkens M.D. David J. Smith Jr. M.D. Marvin M. Kirsh M.D. Steven F. Bolling M.D. Riley S. Rees M.D. 《Journal of cardiac surgery》1993,8(6):671-677
A bstract Since 1980, the automatic implantable cardioverter defibrillator (ICD) has evolved as effective therapy for prevention of sudden cardiac death following documented sustained ventricular tachycardia or fibrillation. During a 5-year period, 412 ICD devices were implanted at the University of Michigan Hospitals with a wound complication rate of 4.1%. In this group, there were 13 infections, 3 erosions of the generator pocket, and 1 wound hematoma. Of the 16 patients with infection or erosion, 12 patients were treated with a rectus abdominis muscle flap closure and 4 with ICD generator removal. In 83% (n = 12) of the muscle flap patients, the wound healed uneventfully. Preoperative chest CT scanning was found to be helpful in identifying probable infection of the epicardial leads. In these cases, all hardware had to be removed to achieve resolution of the infection. We concluded that rectus abdominis muscle flaps were helpful in salvaging infected or exposed ICD generators in the absence of infected epicardial leads. 相似文献
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We outline a proposal for the use of living unrelated kidney donors for transplantation. This proposal, although recommended by the Saudi National Committee on Renal Transplantation, is still under discussion and has not been implemented yet. We feel that this proposal is ethical with airtight safeguards against commercialization and for the protection of the well-being of the donor with assurance that he or she has not been coerced into donation. 相似文献
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Neuropilins and group A plexins are components of receptor complexes for class 3 semaphorins, gradients of which help to guide migration of neural progenitor cells and axonal growth cones during development. We demonstrated previously that neuropilins and class 3 semaphorins are induced in sciatic nerve by crush or transection. We now report that in cultured rat Schwann cells, expression of mRNA encoding neuropilin-2 (NRP2) and plexin-A3 (PlexA3), proteins involved in semaphorin-3F (Sema3F) signal transduction, is diminished markedly by forskolin, an adenylate cyclase activator that, like axonal contact, induces Schwann cell synthesis of myelin lipids and proteins. Interestingly, Schwann cell expression of mRNA encoding NRP1, which participates in Sema3A signaling, is not downregulated by forskolin. Antibodies that recognize ectodomains of NRP2 but not control antibodies prevented cultured Schwann cells from aligning in parallel and forming columns. These results are consistent with the view that in nerves undergoing Wallerian degeneration, Schwann cell NRP2 facilitates assembly of Schwann cells into the tubular aggregates (bands of Büngner) that guide regenerating axons. 相似文献
80.
Cousineau TM Lord SE Seibring AR Corsini EA Viders JC Lakhani SR 《Fertility and sterility》2004,81(3):532-538
OBJECTIVE: To develop and test the feasibility of a theory-driven, psychosocial support CD-ROM prototype for couples in infertility treatment. DESIGN: Focus group meetings with reproductive health experts, semistructured interviews with infertility patients, and content analysis of an infertility message board to determine content domains of the CD-ROM. Usability and acceptance testing of prototype CD-ROM based on predetermined feasibility criteria. SETTING: Private offices and fertility centers. PATIENT(S): Expert panel of 5 reproductive health specialists; interviews with 62 individuals with infertility (35 women, 27 men); feasibility study with 12 patients and 12 experts in reproductive medicine and infertility support. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Product usability/acceptance test. RESULT(S): Participant feedback and content analysis informed the development of a prototype patient education CD-ROM that uses audio, video, interactive tasks, and personalized feedback. Over 80% of participants successfully completed usability tasks, and over 90% rated prototype satisfaction as "good" to "excellent." Some areas were noted for improvement in navigation and refinement in delivery of instructions. Results strongly indicate an interest in an infertility multimedia support tool. CONCLUSION(S): Multimedia methods may serve as an effective, innovative psychosocial intervention for infertility patients and overcome barriers of limited local access to educational and support services. 相似文献