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61.
SH Cheng CM Chen JJ Jian SY Tsai WT Liu MC Liu CM Chen HH Lin 《Canadian Metallurgical Quarterly》1996,95(5):372-377
Breast conservation is not a commonly prescribed treatment option for breast cancer in Taiwan. We report 42 patients with 43 early-stage breast cancers who were treated with breast-conserving surgery and radiotherapy at the Koo Foundation Sun Yat-Sen Cancer Center from April 1990 to December 1994. Included in this study were 33 patients with stage I cancers and 10 with stage II. Breast-conserving surgery consisted of wide local excision and ipsilateral axillary lymph node dissection. Radiotherapy was given 2 to 6 weeks after surgery, with a dose of 46 to 50 Gy, 2 Gy per fraction per day, to the whole breast, and an additional 14 to 18 Gy to the original tumor site. Irradiation to the regional lymph nodes was not performed in patients with negative axillary lymph nodes. Sixteen out of 43 (37%) patients were treated with adjuvant chemotherapy. The local control rate 3 years after treatment was 97% and relapse-free survival was 91%. The cosmetic outcome in 41 treated breasts that were rendered relapse-free by conserving treatment were evaluated and graded by the physicians as excellent, good, fair or poor using a standardized scale. Forty breasts (98%) were scored as excellent or good for their cosmetic results. Breast-conserving surgery and radio-therapy offer Taiwanese women with early breast cancer excellent local control and a highly satisfactory cosmetic outcome. 相似文献
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OBJECTIVES: We sought to characterize the growth of the reconstructed aortic arch after the Norwood operation (NO). BACKGROUND: The first stage of surgical palliation of hypoplastic left heart syndrome (HLHS), the NO, includes augmentation of the aortic arch with homograft. Growth characteristics of the reconstructed aortic arch, which is comprised of both native aortic tissue and homograft, have not been characterized. METHODS: Retrospectively, we examined the serial echocardiograms of 50 patients with HLHS who underwent NO to determine the diameter of the reconstructed transverse arch. Measurements were taken immediately after NO and at two other points (1 to 11 years of age). In addition, the autopsy specimens of 10 other patients with HLHS who underwent NO were examined to determine the contribution of native aortic tissue to the overall size of the reconstructed arch at the time of death (12 to 34 months). RESULTS: The diameter of the transverse aorta increased after NO in all subjects. Its rate of growth paralleled that seen in the normal population, though the reconstructed arch had a significantly larger diameter throughout childhood. Examination of autopsy specimens demonstrated a mean increase in circumference of the native aortic tissue of 0.67 cm (p value <0.01), whereas there was no significant change in homograft circumference. CONCLUSIONS: After reconstruction of the aortic arch in HLHS, the diameter of the arch continues to increase throughout childhood, and this increase is due to growth of the native aortic tissue. 相似文献
64.
Two genetically similar variants of coxsackievirus B4, CB4-P and CB4-V, cause distinct disease syndromes in mice. A multidisciplinary approach was used to examine the events occurring in situ. The CB4-P variant induced acute pancreatitis, followed by repair of the exocrine tissues, while the CB4-V variant induced chronic pancreatitis, characterized by extensive destruction of the exocrine tissues. Since CB4-V replicated more efficiently than CB4-P in vivo, the more extensive tissue injury associated with CB4-V infection could be explained as the result of a higher level of viral replication. However, the fact that CB4-V replicated more efficiently in a mouse strain that survives infection than in a strain that succumbs to infection suggests that immune-mediated mechanisms as well as viral cytolysis may contribute to pancreatic tissue injury. To address the role of the immune system in virus-induced pancreatitis, the cell types within the inflammatory infiltrate were analyzed by flow cytometry. B cells (34 to 75%) were the most abundant, followed by T cells (10 to 30%), natural killer cells (4 to 8%), and macrophages (0 to 6%). Recruitment (and perhaps proliferation) of B and T cells to the pancreatic tissues was influenced by viral strain. Differential recruitment of T and B cells may reflect altered antigenic sites between CB4-P and CB4-V. The viral sequence that affected T- and B-cell recruitment was identified as a threonine residue at position 129 of the VP1 capsid protein. 相似文献
65.
84 patients with 89 primary breast cancers underwent high resolution ultrasound, mammography and histological evaluation. Pathological specimens and hard copy images of both imaging modalities were reviewed in order to document the amount of microcalcification present in each tumour. A total of 44, 40 and 46 tumours had visible microcalcification using high resolution ultrasound, mammography and histology, respectively. Using mammography as the gold standard, ultrasound achieved a sensitivity of 95%, specificity of 87.8% and accuracy of 91% in the detection of microcalcification. Histology had a sensitivity of 80%, specificity of 71.4% and accuracy of 75.3%. We conclude that ultrasound is sensitive in the detection of microcalcification in breast cancer when they are within a mass lesion, and is a reliable diagnostic sign of carcinoma when present. 相似文献
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SO Trerotola MS Johnson H Shah MA Kraus MA McKusky WT Ambrosius VJ Harris JJ Snidow 《Canadian Metallurgical Quarterly》1998,207(2):491-496
OBJECTIVE: The purpose of this study was to determine the feasibility of high-resolution sonography for the detection of meniscal cysts and associated meniscal tears and for the differentiation of meniscal cysts from other masses at the knee joint. SUBJECTS AND METHODS: Fifty consecutive patients (51 knees) with a palpable mass at the knee joint were examined prospectively using a 7.5-MHz annular array transducer. Mass consistency and location and meniscal integrity were evaluated. Sonographic findings were correlated with surgery (46/51) and histopathology (15/51). Five patients did not undergo surgery. RESULTS: At surgery, 32 masses appeared to be meniscal cysts, whereas 19 were other types of masses. Sonographically, 31 of the 32 meniscal cysts were diagnosed correctly. Sonographic differentiation of the other types of masses from meniscal cysts could reliably be made in 17 of 19 cases; two masses were falsely interpreted as meniscal cysts. Sensitivity, specificity, and accuracy of sonography in the depiction of meniscal cysts were 97%, 86%, and 94%, respectively. The positive predictive value was 94% and the negative predictive value was 92%. Meniscal tears (31/46) and meniscal tears concomitant with meniscal cysts (26/32) were detected with an accuracy of 83% and 88%, respectively. CONCLUSION: Sonography is an accurate imaging technique for the detection of meniscal cysts and associated meniscal tears. Differentiation of meniscal cysts from other cystic and solid masses at the knee joint can be reliably made with sonography. 相似文献
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The anatomical relationship between vagal afferents and brain nitric oxide synthase containing terminals in the nucleus tractus solitarii was studied by means of anterograde tracing combined with immunocytochemistry and immuno-electron microscopy. Biotinylated dextran amine was injected into the nodose ganglion with a glass micropipette. Four to eight days following the injection, regions of the nucleus tractus solitarii containing biotinylated dextran amine-labelled vagal afferents and those containing nitric oxide synthase-immunopositive terminals were congruent. Many neurons exhibiting nitric oxide synthase immunoreactivity were found within the biotinylated dextran amine-containing terminal field. However dense labeling of terminals with biotinylated dextran amine precluded determination if the terminals were nitric oxide synthase-immunoreactive. Therefore, we combined degeneration of vagal afferents after removal of one nodose ganglion with nitric oxide synthase immuno-electron microscopy. Axon terminals that possessed characteristic vesicle clusters and were partially or completely engulfed by glial processes were identified as degenerating vagal afferents. Degenerating axon terminals comprised 38% of the total axon terminals in the nucleus tractus solitarii in a sample of sections; and of the degenerating axon terminals, 67% were nitric oxide synthase-immunoreactive. Nitric oxide synthase immunoreactivity was present in 41% of the non-degenerating axon terminals. Prominent staining of dendrites for nitric oxide synthase immunoreactivity indicated that much of the nitric oxide synthase in the nucleus tractus solitarii is not derived from peripheral afferents. Of the total number of dendritic profiles sampled, half were nitric oxide synthase-immunoreactive. Our data support the hypothesis that nitric oxide or nitric oxide donors may be present in primary vagal afferents that terminate in the nucleus tractus solitarii. While this study confirms that vagal afferents contain brain nitric oxide synthase, it demonstrates for the first time that the majority of nitric oxide synthase immunoreactivity in the nucleus tractus solitarii is found in intrinsic structures in the nucleus. In addition, our data show that second or higher order neurons in the nucleus tractus solitarii may be nitroxidergic and receive both nitroxidergic and non-nitroxidergic vagal input. 相似文献