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81.
J B Beckwith  N F Palmer 《Cancer》1978,41(5):1937-1948
Detailed histological analysis of 427 cases entered on the first National Wilms' Tumor Study revealed that lesions with foci of marked cytological atypism (anaplasia), and those composed predominantly of sarcomatous stroma, were associated with unfavorable outcome. Twenty-five patients had anaplasia, and 24 had sarcomatous lesions of which a total of 28 (57.1%) died of tumor. Three hundred and seventy-eight patients had tumors which showed neither of these features, and only 26 (6.9%) died of tumor. Seven of ten deaths due to tumor in patients diagnosed before two years of age were associated with sarcomatous lesions. Three sarcomatous patterns were recognized, of which one, designated "clear cell" sarcoma, had a predilection for bony metastases. Using criteria defined and illustrated in this paper it is possible to identify in advance those patients likely to do poorly using current therapeutic approaches.  相似文献   
82.
A total of 410 colposcopic examinations were performed on 188 female cebus monkeys that were under study to determine the oncogenic potential of herpes simplex virus type 2 in this genus. A split-cone vaginal speculum was developed that permitted good observation of the vaginal cervix in the cebus monkey. The cervical anatomy of cebus monkeys was found to differ from that of humans in that the surface of the animal cervix was more papilliform, with thinner squamous epithelium, and the squamocolumnar junction lay within the endocervical canal. Therefore, the ability to detect abnormalities in the cervical epithelium by colposcopic examination in the cebus monkey was restricted to vascular changes in the squamous epithelium. After 100 examinations, several vascular patterns were distinguishable and interpretations of these patterns were compared with cytologic findings on the same animals. Findings by both cytology and colposcopy were mild in nature; no carcinoma was detected. Colposcopic and cytologic findings correlated at a level of 84%. More abnormalities were detected with colposcopy than with use of cytologic techniques.  相似文献   
83.
84.
We compared the peripheral blood and periprosthetic tissues of 53 patients at revision arthroplasty with those of 30 patients at primary arthroplasty to determine whether there is a systemic difference in lymphocytes in patients with worn hip implants. The absolute number and relative proportion of lymphocytes bearing CD2, CD3, CD4, CD8, CD16, CD19, HLA-DR, kappa and lambda antigens were compared with the levels of IL-1beta, IL-6 and PGE2 in the pseudosynovial membrane as well as with a semiquantitative estimate of metal and polyethylene particles, necrosis and chronic inflammation and the total concentration of metals within the periprosthetic tissues. There was a significant increase in the relative proportion of CD2-positive T-cells and CD16-positive natural killer cells in the peripheral blood at revision arthroplasty compared with primary arthroplasty and an increased proportion of CD8-positive T-cells and a decreased ratio of CD4 to CD8 (helper inducer/suppressor cytotoxic cells). Three control patients, who went on to have revision surgery, had values at primary arthroplasty which were similar to those of patients at the time of revision surgery. These differences did not correlate with the local concentration of metal, plastic or cement or inflammatory response or the type of prosthesis. An inverse correlation was noted between the necrosis in the periprosthetic tissue and both the local production of IL-6 and the absolute numbers of T-cells in peripheral blood. We conclude that there may be several cell-mediated systemic immune responses to aseptic loosening, at least one of which may be directly related to events in the periprosthetic tissues. We cannot exclude the possibility that the changes in the proportion of CD8-positive cells reflected a predisposition, rather than a reaction, to loosening of the implant.  相似文献   
85.
PURPOSE: To compare the effectiveness and side effects of methadone and morphine as first-line treatment with opioids for cancer pain. PATIENTS AND METHODS: Patients in international palliative care clinics with pain requiring initiation of strong opioids were randomly assigned to receive methadone (7.5 mg orally every 12 hours and 5 mg every 4 hours as needed) or morphine (15 mg sustained release every 12 hours and 5 mg every 4 hours as needed). The study duration was 4 weeks. RESULTS: A total of 103 patients were randomly assigned to treatment (49 in the methadone group and 54 in the morphine group). The groups had similar baseline scores for pain, sedation, nausea, confusion, and constipation. Patients receiving methadone had more opioid-related drop-outs (11 of 49; 22%) than those receiving morphine (three of 54; 6%; P =.019). The opioid escalation index at days 14 and 28 was similar between the two groups. More than three fourths of patients in each group reported a 20% or more reduction in pain intensity by day 8. The proportion of patients with a 20% or more improvement in pain at 4 weeks in the methadone group was 0.49 (95% CI, 0.34 to 0.64) and was similar in the morphine group (0.56; 95% CI, 0.41 to 0.70). The rates of patient-reported global benefit were nearly identical to the pain response rates and did not differ between the treatment groups. CONCLUSION: Methadone did not produce superior analgesic efficiency or overall tolerability at 4 weeks compared with morphine as a first-line strong opioid for the treatment of cancer pain.  相似文献   
86.
BACKGROUND: Fetal pancreatic tissue has been suggested to be less immunogenic than adult islets. Thus, transplantation of human fetal pancreatic tissue as treatment for type 1 diabetes has been gaining interest. To investigate this question, we tested the peripheral blood mononuclear cell (PBMC) responses from different subject populations to human adult islet proteins (AIP) versus human fetal pancreatic proteins (FPP). METHODS: PBMC responses to FPP and AIP from normal controls (n=14), newly diagnosed type 1 diabetes patients (n=5), long-term type 1 diabetes patients (n=9), and subjects at-risk for development of type 1 diabetes (n=3) were studied. RESULTS: We observed that normal controls demonstrated PBMC reactivity to 0-3 molecular weight regions (mwr) for both the AIP (mean+/-SD, 0.8+/-1.1) and the FPP (0.6+/-0.7). In contrast, newly diagnosed type 1 diabetic patients (<1 year) demonstrated PBMC responses to 9-16 mwr for the AIP (12.8+/-2.5) and 0-14 mwr for the FPP (6.8+/-5.0). The PBMCs from long-term type 1 diabetes patients (> 3 years) were responsive to 2-11 mwr for AIP (6.0+/-2.8) and 0-11 mwr for FPP (4.9+/-4.0). Three nondiabetic ICA positive subjects at-risk for development of type 1 diabetes demonstrated positive PBMC reactivity to 9-18 mwr for the AIP (12.7+/-3.9) and 4-18 mwr for the FPP (10.0+/-5.9). CONCLUSIONS: We conclude that human fetal pancreatic proteins are not significantly less stimulatory than human adult islet proteins to PBMCs of subjects with or at risk for type 1 diabetes.  相似文献   
87.
Previous work on in-situ calibration of force platforms has focused primarily on behaviour under static loading conditions. The prototype described in this paper is a dynamic system, designed to approximate the loading profile generated during human gait. The design, construction and performance of an oscillating lead pendulum assembly is described; including three-dimensional visual performance assessment and rigorous multi-component force analysis. No significant difference was found between measured data and a theoretical profile for vertical force and angular displacement. A significant difference was found for the horizontal force component. The authors believe that further development of this prototype model will allow accurate routine dynamic calibration.  相似文献   
88.
We performed an in vitro study to determine the thermal safety of a domestic microwave to warm intravenous crystalloid solutions. Five-hundred-millilitre bags of crystalloid, randomly allocated to groups which differed in power setting, timer setting and whether or not agitation was performed after warming, were heated in a microwave oven to a calculated temperature of 39 degrees C. Timer accuracy was checked by stopwatch. Bag temperature was measured using an infrared tympanic temperature probe and fluid temperature was measured with an in-line thermocouple. Mean times measured by stopwatch were higher than set. No in-line temperatures reached 40 degrees C. Wider overall ranges and a higher mean were found with the tympanic probe compared with in-line temperature measurement. There were significant differences between the in-line temperatures of shaken and unshaken bags at each power setting, but not when groups were added together. There was no change in colour or odour of bags or fluid. One bag developed a pinhole leak when the packaging was removed.  相似文献   
89.
90.
This study was carried out to define the post-treatment appearance of the chest radiographs in 44 consecutive patients with Hodgkin disease who received mantle irradiation with or without chemotherapy and to determine how the incidence and severity of post-treatment abnormalities relate to the radiation parameters and chemotherapeutic regimens. Radiographs of the chest in 44 patients, computed tomograms of the chest in 31 patients and of the abdomen of 35 patients were reviewed, prior to and following treatment, for mediastinal contours, pericardial status, cardiac size and pulmonary fibrosis. All patients were followed for a minimum of 1 year and 27 were followed for more than 5 years. Stable post-treatment imaging studies were correlated with the initial extent of disease, radiation parameters, and chemotherapeutic regimens. Stable post-treatment findings were categorised as follows: the chest radiograph was normal or showed subtle vascular reorientation; moderate paramediastinal fibrosis was present; severe pulmonary fibrosis had occurred with narrowing of the cardiomediastinal silhouette in some patients. In general, the severity of the fibrosis was dependent on (1) the size of the radiation fields and on whether or not the coverage of the hila included a 1- to 2-cm margin; (2) the amounts of chemotherapy and particularly bleomycin containing regimens and (3) individual susceptibility of normal tissue irradiation. Therapy for Hodgkin disease is not necessarily associated with radiographic sequelae regardless of the initial status of the mediastinum or the treatment. However, the post-treatment appearance of the chest radiographs in this study was related strongly to (1) the initial extent of disease and particularly the status of the hila, both of which influenced the amounts of lung parenchyma that were included in the treatment fields; (2) the use of bleomycin in chemotherapy regimens and (3) individual normal tissue radiosensitivity.  相似文献   
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