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11.
One hundred and twelve bilateral thyroidectomies for solitary thyroid nodules with suspected malignancy were performed. The incidence of malignancy in the 112 primary nodules was 42%. Twenty-nine of the 112 contralateral lobes (26%) contained malignancy, which was unsuspected in 80%. Of these 29, 20 were foci of papillary cancer < or = 5 mm and 9 were larger papillary tumors or follicular carcinoma. We analyzed these 112 patients to determine whether there was a simple method to identify those patients at risk for contralateral, unsuspected malignancy. With use of the AMES clinical staging retrospectively, 70 of the 112 patients were classified as having low-stage disease. Fifty percent (35) had cancers on the primary side and 27% (19) on the contralateral side. Of these 19 contralateral cancers, 14 were papillary cancers < or = 5 mm, 4 were papillary cancer > 5 mm and one was a 1.5 cm follicular carcinoma, a similar distribution as in the whole group of 112. When the AMES analysis then excluded those thought to be at risk for multicentricity or papillary carcinoma and examined female patients only with nonpapillary frozen sections, nonpapillary aspiration cytological results, and no history of radiation exposure, no further reduction in the proportion of contralateral cancers (7 of 26, 27%) was found. Fifty-five of the 112 patients underwent preoperative ultrasound scans. In those cases in whom the contralateral lobe had no intraoperative palpable or preoperative sonographic mass, 5 of 20 still had contralateral cancers, but all were papillary < or = 5 mm.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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OBJECTIVE: To evaluate angiogenesis in squamous cell carcinoma in situ (CIS) and microinvasive squamous cell carcinoma of the uterine cervix and to investigate the relations among angiogenesis, stromal inflammation, and depth of invasion. METHODS: Three groups of women were studied: 22 controls who had undergone hysterectomy for benign conditions; 18 with squamous cell CIS of the cervix who underwent cone biopsy, hysterectomy, or both; and 14 with microinvasive squamous cell carcinoma who underwent conization of the cervix and subsequent surgical management according to depth of invasion. All specimens were stained immunohistochemically for factor VIII-related antigen. Areas below the basement membrane with the highest angiogenic density were selected. The degree of stromal inflammatory reaction was assessed. Statistical analyses included Kruskal-Wallis, analyses of variance and covariance, Scheffe and Bonferroni-Dunn post hoc procedures, and Pearson correlation analysis. P < .05 was considered statistically significant. RESULTS: Microvessel counts per high-power field (x 400) of microinvasive squamous cell carcinoma of the cervix differed significantly from those of controls and squamous cell CIS (median 34.5 per high-power field, range 9-76 versus median 17, range 7-47, and median 19, range 8-39, respectively; P < .005). Microvessel counts per high-power field in squamous cell CIS did not differ significantly from those of controls (P = .91). Among patients with microinvasive squamous cell carcinoma of the cervix, no significant correlation was found between microvessel counts per high-power field and the depth of invasion (r = 0.19, P = .51). Stromal inflammatory reaction (graded 0-3) differed significantly among controls, squamous cell CIS, and microinvasive carcinoma (mean 0.40, 0.83, and 1.64, respectively; P < .005). CONCLUSIONS: Microinvasive squamous cell carcinoma of the uterine cervix is angiogenic, but depth of invasion is not associated with increased angiogenicity. Squamous cell CIS is not angiogenic. 相似文献
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SI Alexander SB Younes JJ Yunis D Zurakowski N Mirza D Dubey MP Drew WE Harmon EJ Yunis 《Canadian Metallurgical Quarterly》1997,63(12):1756-1761
BACKGROUND: Recipient antidonor cytotoxic T-cell activity has been associated with graft loss and acute rejection in renal allograft recipients. The role of immunologic mechanisms in the development of chronic graft rejection is controversial. We analyzed all living related renal transplants performed at Children's Hospital (Boston, MA) from 1983 to 1995 to assess whether cell-mediated cytotoxicity, determined in vitro and measured before transplantation, was predictive of chronic rejection. METHODS: Eighty-three patients were studied retrospectively. Fifty-seven patients with one haplotype-matched renal transplants from living related donors were studied to determine the association between cell-mediated lympholysis (CML) level, acute rejection, chronic rejection, and graft failure. Acute rejection was defined by the decision to treat. Chronic rejection was defined by histology and/or the absolute serum creatinine value using an increasing serum creatinine level >1.0 mg/dl for children less than 3, a creatinine level >1.5 mg/dl for children between 3 and 10 years of age, and a creatinine level >2.0 mg/dl for children above 10 years of age. Return to dialysis or retransplantation was considered graft failure. RESULTS: Of the 57 haploidentical patients, there were 33 males and 24 females. The mean age at transplant was 11.1 years (SD=6.7). Twelve patients developed chronic rejection, 24 patients developed acute rejection, and 7 patients had graft failure. Pretransplant cytotoxic T lymphocyte activity was associated with chronic rejection (P=0.001) and graft failure (P=0.013) but only marginally with acute rejection (P=0.058). Controlling for age and sex, Cox's proportional hazards model revealed that CML level was predictive of time to chronic rejection (P<0.01) but not acute rejection (P=0.11). It was estimated that every 1-unit increase in CML level raises the monthly risk of chronic rejection by 7%. Ten children received HLA-identical kidneys from their siblings. There were no episodes of chronic rejection after 5 years. Two patients with high CML levels had episodes of acute rejection; both patients responded to treatment. CONCLUSION: Our data demonstrate an association between pretransplant cell-mediated cytotoxicity and the occurrence of chronic rejection in living related one-haploidentical renal transplants in pediatric patients. 相似文献
14.
J Barrette R Bellwied P Braun-Munzinger WE Cleland T Cormier G Dadusc G David J Dee O Dietzsch M Fatyga SV Greene JV Germani JR Hall TK Hemmick N Herrmann RW Hogue B Hong K Jayananda D Kraus BS Kumar R Lacasse D Lissauer WJ Llope TW Ludlam R Majka SK Mark JT Mitchell M Muthuswamy E O'Brien C Pruneau FS Rotondo da Silva NC J Simon-Gillo U Sonnadara J Stachel H Takai EM Takagui TG Throwe L Waters C Winter D Wolfe CL Woody N Xu Y Zhang Z Zhang C Zou 《Canadian Metallurgical Quarterly》1995,52(5):2679-2683
15.
Ventricular rupture is a catastrophic, often fatal complication of myocardial infarction. We present a unique case of left ventricular rupture into the coronary sinus that was diagnosed by two-dimensional Doppler echocardiography in a patient with a recent inferior myocardial infarction. The echocardiographic findings essential to diagnosis were subsequently confirmed at autopsy and are reviewed in detail. 相似文献
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Preimplantation mouse embryos (n = 1540) were cultured in the presence of platelet-activating factor (PAF) (10(-7)- 10(-14) mol/l) to the hatched blastocyst stage. A dose-dependent negative correlation (-0.75783) relationship between blastocysts and the concentration of PAF was statistically significantly different (p < 0.001). Long-term but not short-term PAF exposure is detrimental to preimplantation Swiss Webster mouse embryos. Short-term PAF (10(-9) mol/l) exposure was found significantly (p < 0.05) to reduce blastocoel diameter. The effect of PAF during preimplantation development may be genotype dependent and be affected by the culture conditions. 相似文献
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