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51.
BACKGROUND: Increasing evidence suggests significant disparity in colorectal cancer outcomes between black and white patients. Contributing factors may include advanced tumor stage at diagnosis, differences in treatment, more aggressive tumor biology, access to care, and patient comorbidity. HYPOTHESIS: Disparities in colorectal cancer outcomes exist despite similar objective measures of treatment. DESIGN AND SETTING: Ten-year retrospective review of all patients with colorectal cancer using tumor registries at a city hospital (n = 83) and a university medical center (n = 585) in the same city. We assessed stage at diagnosis; curative surgical resection; use of adjuvant treatment; overall, disease-free, and stage-specific survival; and socioeconomic status. Patients with nonwhite, nonblack ethnicity (4% overall) were excluded. Differences in stage and treatments were compared using the chi(2) test, and median survival rates were compared using log-rank tests. RESULTS: Significantly more black patients were treated at the city hospital (53.0%) vs the university medical center (10.6%) (P<.001). No differences were identified in stage distribution or treatments received between hospitals or between black and white patients. Significantly worse survival was noted among patients treated at the city hospital (2.1 vs 5.3 years; P<.001) and among black patients treated at both institutions (city hospital: 1.4 vs 2.1 years, and university hospital: 3.2 vs 5.7 years; P<.001 for both). Disease-free survival rates showed similar significant reductions for black patients at both institutions. There was no association between survival and socioeconomic status at either institution. CONCLUSION: The marked reductions in overall and disease-free survival for black patients with colorectal cancer do not seem to be related to variation in treatment but may be due to biologic factors or non-cancer-related health conditions.  相似文献   
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Basal cell carcinomas (BCCs) typically occur in middle-aged to elderly patients but less commonly in younger ones. In our experience, most BCCs seen in patients younger than 40 years are found in women. We evaluated 30 women with biopsy-proven BCC and 30 control patients matched for sex, age, and skin type to determine potential risk factors for this population. Tanning bed visits, pack-years of cigarette smoking, recreational sun exposure, number of blistering sunburns, and use of sunscreens were determined for both groups. Among patients with a BCC, the histologic type of tumor, site of involvement, method of treatment, follow-up period, incidence of recurrence, and presence of actinic keratoses were also evaluated. Patients with a BCC had a statistically greater number of pack years of smoking (P =.045), and a greater percentage of these women had experienced blistering sunburns (P =.028). Although women with a BCC had, on average, almost twice as many tanning salon visits (152.2 vs 83.1), this was not statistically significant. Sunscreen use and amount of recreational ultraviolet light exposure were essentially equal between the two groups. Young women with a BCC are more likely to have a past or current history of cigarette smoking and blistering sunburns. Repeated exposure to tanning beds may also be a contributory factor.  相似文献   
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Background. The use of radiographic contrast media in the setting of possible bowel ischemia and potential perforation is known to be associated with increased clinical risk. However, there is a lack of controlled studies using a standard native fecal load to define and compare the intrinsic mortality and morbidity among options of contrast media currently available to the radiologist. We have compared the mortality and gross and histopathologic morbidity of a standard intraperitoneal native fecal dose in the guinea pig, using barium, two iodinated media, saline and air.¶Materials and methods. The study was performed on adult Hartley guinea pigs. A standard native fecal solution with a colony count of 108 aerobes and 2 × 107 anaerobes was prepared, and the LD50 of intraperitoneal injection of the solution was determined. The standard solution at the LD50 dose was then used to compare the mortality and morbidity when commercial barium sulfate (18 % w/v), Conray 30 (iothalamate meglumine 30 %), 1:1 dilution of Conray 30 with sterile water, termed Conray “15” (iothalamate meglumine 15 %), saline and air, were added to the intraperitoneal injection of the fecal solution in five groups of 20 animals each. Mortality and acute (96 h) and chronic (30 days) gross and histopathology were assessed and graded according to a standard system and analyzed statistically.¶Results. Barium was significantly more deleterious than the dilute water-soluble iodinated media, saline and air. Mortality occurred within 24 h in the barium group and within the initial 48 h in all groups as follows: barium 19/20 (95 %); Conray 30 16/20 (80 %); Conray “15”¶7/20 (35 %); saline 0; air 0. Acute gross and histopathology showed extensive grade 4 lesions in 19/19 barium animals; less severe lesions were present in a lesser percentage of the animals in the other four groups. Entirely chronic lesions were present only in the single surviving barium animal and were non-significant (<400 μm) or absent in the other four groups.¶Conclusions. In our study, barium incurred the most significant deleterious short and long-term effects in the setting of fecal peritonitis. Dilute water-soluble media offer a much greater margin of safety. Saline under sonographic guidance is less deleterious than any of the positive radiographic contrast media. However, in our study, air was the safest contrast medium in the setting of peritoneal soiling.  相似文献   
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Patterns of practice survey for nonsmall cell lung carcinoma in the U.S   总被引:3,自引:0,他引:3  
Choy H  Shyr Y  Cmelak AJ  Mohr PJ  Johnson DH 《Cancer》2000,88(6):1336-1346
BACKGROUND: Nonsmall cell lung carcinoma comprises approximately 75% of all lung carcinoma cases in the U.S. Newly evolving strategies have created considerable controversy regarding the optimal treatment for patients diagnosed with this disease. METHODS: A 17-item survey was designed to collect demographic data and information regarding practice patterns for nonsmall cell lung carcinoma, including patient assessment, treatment approaches, and roles of chemotherapy and radiotherapy. Surveys were mailed in the summer of 1997 to approximately 9200 oncologists of all types throughout the U.S. Practice settings included private office, private hospital, academic, university-affiliated office, government, and Veterans Administration institutions. RESULTS: Approximately 10% of the oncologists responded (n = 979), including 499 medical oncologists (51%), 464 radiation oncologists (47%), and 16 others (2%). For the adjuvant treatment of surgically resected N1-2 disease, combined modality treatment was preferred over radiation therapy alone by medical oncologists (48% vs. 16%; P<0.001) and radiation therapy alone was preferred over combined modality treatment by radiation oncologists (55% vs. 38%; P<0.001). The combination of paclitaxel and carboplatin was the preferred first-line regimen for all stages of nonsmall cell lung carcinoma by the majority of medical oncologists (55%), whereas the majority of radiation oncologists (58%) chose the combination of etoposide and platinum. With regard to the optimal combined modality approach, respondents were divided evenly between concurrent chemoradiotherapy (34%) and sequential chemoradiotherapy (31%). Overall, respondents reported basing treatment decisions largely on published literature (55%) compared with personal experience (19%), seminars and colleagues (16%), and clinical trial availability (10%) (P<0.001). CONCLUSIONS: This survey confirms many differences in practice patterns among medical oncologists and radiation oncologists in the treatment of patients with nonsmall cell lung carcinoma and suggests the need for the multidisciplinary management of this entity. In addition, the current study demonstrates that reliance on the medical literature as a basis for treatment steadily declines the longer the physician has been in practice.  相似文献   
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Vico  JJ; Larsen  CR 《Radiology》1979,131(3):636
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The objective of this study was to evaluate the proliferation and the multiple-lineage differentiation capacity when bone marrow mesenchymal stem cells (BMSCs) were cultured short-term in autologous serum/plasma instead of fetal calf serum (FCS). The BMSCs from 12 donors were cultivated individually in 10% autogenic plasma or serum, with or without bFGF and EGF growth factors. Cell proliferation was examined by a Tetrazolium assay (MTT) after passages 1, 3, and 5. A medium supplemented with 10% human plasma or serum was sufficient to propagate BMSCs. However, no significant proliferation was shown when bFGF and EGF (20 ng/mL each) were added into the medium with autologous serum/plasma. We examined, inductions of adipogenesis, osteogenesis, and chondrocytogenesis, as capacities of multiple-lineage differentiation of cultivated BMSCs (passages 8). Differentiation was investigated by both RT-PCR and immunohistochemistry staining (IHC). Qualitative evidence demonstrated the differentiation capacity was preserved in cultivated BMSCs with autologous serum/plasma.  相似文献   
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This cases report compared the short-term changes of BLL with medical removal intervention and follow-up the long-term changes of BLL afterward. During a physical examination in October 1992, a 44-year old shipyard welder was discovered to have a blood lead level (BLL) of 54.1 microg/dl. It was recommended that the shipyard remove this worker from his workplace. In 1993 the BLLs checked for this worker were 36.7 microg/dl in March and 32.0 microg/dl in April. After six months of medical removal, he returned to initial welding work. In 2002, we collected two blood samples from this worker for analysis in May and October. The results were 30.4 microg/dl and 31.6 microg/dl, respectively. Meanwhile, two other welding workers (case 2 and case 3) with BLLs over 40 microg/dl in the survey conducted at the same shipyard in 1992. It took 4 yr to let BLLs downed to less than 40 microg/dl. However, after the blood lead concentration drops to below 40 microg/dl, 10 yr long-term observation indicates that BLLs reduction level off and do not continue to go down in these three cases.  相似文献   
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