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21.
Between 1977 and 1986, 75 black and 615 white women with American Joint Committee (AJC) Stages I and II breast cancer were treated with excisional biopsy, axillary dissection, and radiation therapy for breast conservation. Cyclophosphamide, methotrexate, and 5-fluorouracil, with and without prednisone and tamoxifen, was given to 92% of premenopausal, 83% of perimenopausal, and 63% of postmenopausal node-positive women; 20 of 106 (19%) postmenopausal node-positive women received tamoxifen only. The clinical characteristics of the similarly treated patients were compared. The 5-year actuarial local only first failure rate was 5% for black women and 6% for white women (P = 0.53). Regional only failure as the first site of failure was 9% for blacks versus 1% for whites (P = 0.002), with regional recurrence as any component of first failure being 16% for blacks and 4% for whites (P = 0.001). The supraclavicular fossa was identified as the primary site of regional recurrence in black patients with either pathologically positive or negative axillae. Distant metastases as the only site of first failure were significantly greater in the black population with a 20% 5-year actuarial failure rate versus 11% in white patients (P = 0.01). The 5-year actuarial overall survival for the black patients was 82% versus 91% for the white patients (P = 0.01), with no-evidence-of-disease (NED) survival being 64% and 83% (P = 0.0002) and relapse-free survival (RFS) being 61% and 77% (P = 0.01), respectively. Black patients younger than 40 years of age or with pathologically positive axillary nodes had significantly worse NED, RFS, and overall survival compared with similarly staged white patients. Cosmetic results were analyzed at 3 and 5 years after completion of therapy. Although significantly fewer black patients had an excellent-to-good cosmetic result at 3 years compared with white patients, the results were not significantly different at 5 years. These results show that appropriately selected black patients with early stage breast cancer have excellent local control after conservative surgery and radiation therapy and should continue to be offered breast preservation as an alternative to mastectomy. Patterns of failure, however, demonstrated higher regional and distant recurrence rates and lower NED, RFS, and overall survival rates in most subsets of black patients reviewed.  相似文献   
22.
Fetal tissues from 16 spontaneous abortions, two terminations, and one perinatal death, 18 of which were associated with maternal human parvovirus B19 infection, were examined for B19 infection by histology and in situ hybridization using a digoxigenin-labeled B19-DNA probe. In 15 spontaneous abortions and one termination, erythroblasts with intranuclear inclusions (lantern cells) reacted with B19-DNA by in situ hybridization. No internal or external fetal malformations were observed. Because 13 (86.7%) spontaneous abortions with lantern cells occurred between the 20th and 28th weeks of gestation, it is postulated that B19 infection may be a particular threat to the fetus during this stage of gestation.  相似文献   
23.
The effects of local tumor hyperthermia on regional lymph node metastases are inconclusive. We studied the effects of hyperthermia on the incidence of popliteal, femoral, and abdominal lymph node metastases in C57BL/6 mice with primary B16 melanomas (F10 variant) growing subcutaneously in the left foot. Tumors were heated to 42.3, 43.5, and 44.2 degrees C for 90 minutes either 7 days after inoculation of 5 X 10(4) viable cells (microscopic tumor = mic) or when the tumors were approximately 3 mm in diameter (macroscopic tumor = mac). Femoral lymph node metastases occurred in 0/21 control animals and in 8/22 (36%), 11/19 (58%), and 11/17 (65%) animals whose primary tumors were heated to 42.3, 43.5, and 44.2 degrees C, respectively. For all three treatments, the increase in metastases as compared to controls was statistically significant (p less than 0.004, Fisher's exact test). The incidence of abdominal lymph node metastasis was slightly higher in the treated groups than controls. Twenty of 21 (95%) control mice developed popliteal lymph node metastases and hyperthermia-induced increases could not be demonstrated. Fifteen of 21 control mice killed 3 weeks after amputation of tumor-containing leg had pulmonary metastases with an average of 6 +/- 4 (standard deviation) lesions per affected mouse. Pulmonary metastases occurred in 22/22 (100%), 17/19 (89%), and 13/17 (76%) of mice whose tumors were heated to 42.3, 43.5, and 44.2 degrees C, respectively. The numbers of metastases for affected mice were significantly increased compared to controls for tumors heated to 43.5 and 44.2 degrees C (28 +/- 43, 43 +/- 52, 119 +/- 121, p greater than 0.02, p less than 0.006, p less than 0.002, for two sample T-test). While 0/8 mic tumors were cured 5/9 mac tumors heated to 44.2 degrees C disappeared (p less than 0.03, Fisher's exact test) and there was a growth delay in the remaining mice. Mic tumors, heated to 43.5 degrees C, had an accelerated onset of growth while mac tumors heated to this temperature had a slight growth delay. Growth of both mic and mac primary tumors heated to 42.3 degrees C was similar to controls. These results show that therapeutic and subtherapeutic local hyperthermia increases metastases to regional lymph nodes and to lungs even when primary tumor growth rate is partially or totally controlled.  相似文献   
24.
25.
A sampling and analytical procedure for methyl-, dimethyl-, ethyl-, and diethylamine was developed in order to avoid problems typically encountered in the sampling and analysis of low molecular weight aliphatic amines. Samples are collected with adsorbent tubes containing Amberlite XAD-7 resin coated with the derivatizing reagent, NBD chloride (7-chloro-4-nitrobenzo-2-oxa-1,3-diazole). Analysis is performed by high performance liquid chromatography with the use of a fluorescence and/or UV/visible detector. All four amines can be monitored simultaneously, and neither collection nor storage is affected by humidity. Samples are stable at room temperature for at least two weeks. The methodology has been tested for each of the four amines at sample loadings equivalent to air concentration ranges of 0.5 to 30 ppm for a sample volume of 10 liters. The method shows promise for determining other airborne primary and secondary low molecular weight aliphatic amines.  相似文献   
26.
We report a case of dislocation of the second through fifth carpometacarpal joints and review the mechanism of injury and radiographic findings in such injuries.  相似文献   
27.
28.
Two simultaneous surveys were conducted by the Association of Residents in Radiation Oncology (ARRO). A survey of all residents in Radiation Oncology was conducted to obtain information on trends in residency training. A simultaneous survey of Chief Residents was obtained to determine more specific information on current training programs. Over one-half of residents responded. Eighty-eight percent of respondents were graduates of a North American medical school. Most did at least an internship prior to entering Radiation Oncology and 3/4 of those who did not do a separate internship rotated through other areas at a later time to broaden their knowledge. One-half are Board certified or Board eligible in another specialty or hold a Masters or Ph.D. degree. Three-quarters of all residents had authorship of at least one paper during training and one-half were primary authors. Eighty percent felt adequately prepared for practice after residency. One-half plan at least an initial post-residency affiliation with an academic center. Many were concerned that Radiation Oncologists are not afforded respect equivalent to that of other specialties. Ninety-eight percent favored departmental status for Radiation Oncology. Resident recommendations for improving the image of Radiation Oncology are presented.  相似文献   
29.
30.
Prion infections of the central nervous system (CNS) are characterised by a reactive gliosis and the subsequent degeneration of neuronal tissue. The activation of glial cells, which precedes neuronal death, is likely to be initially caused by the deposition of misfolded, proteinase K-resistant, isoforms (termed PrP(res)) of the prion protein (PrP) in the brain. Cytokines and chemokines released by PrP(res)-activated glia cells may contribute directly or indirectly to the disease development by enhancement and generalisation of the gliosis and via cytotoxicity for neurons. However, the actual role of prion-induced glia activation and subsequent cytokine/chemokine secretion in disease development is still far from clear. In the present work, we review our present knowledge concerning the functional biology of cytokines and chemokines in prion infections of the CNS.  相似文献   
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