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21.
Preoperative cytologic examinations were performed on bronchial material from 92 patients with postsurgical (pathologic) stage I (American Joint Committee) adenocarcinoma of the lung. All patients were followed up for at least 5 years or until death; thus, cases of adenocarcinoma metastatic to the lungs were virtually excluded. Only 22 patients (24%) had abnormal preoperative cytologic findings. This low cytologic sensitivity is ascribed to the small size and peripheral location of the tumors. Large lesions of high histologic grades were more likely to have positive preoperative cytologic findings than small, well-differentiated ones.  相似文献   
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Long-term treatment of mouse cancer cells with interferon-alpha (IFN-alpha) converts parental B16 melanoma cells to B16alpha vaccine cells. Inoculation of syngeneic mice with B16alpha vaccine cells triggers immunity to the parental B16 tumor that is mediated by host macrophages, T cells, and natural killer (NK) cells. Lymph node cells from mice inoculated with irradiated B16alpha vaccine cells, but not with irradiated parental cells, proliferate when cultured in vitro, suggesting long-term in vivo activation of lymphoid cells. Long-term IFN-alpha treatment of B16alpha vaccine cells induced both interleukin-15 (IL-15) mRNA and IL-15 protein. The bulk of the induced IL-15 remained cell associated, either cytoplasmic or associated with the cell membrane. Immunofluorescence microscopy studies showed that the cell-associated IL-15 was broadly distributed throughout the cytoplasm. These observations suggest that long-term IFN-alpha treatment may induce primarily the truncated isoform of IL-15. Vaccination with irradiated B16alpha vaccine cells may promote tumor immunity by releasing high levels of cell-associated IL-15 when spontaneously lysed or directly killed by innate immune cells. The release of accumulated cell-associated IL-15 may then trigger a host T cell response to tumor antigens and cause host development of immunity to the B16 tumor cells.  相似文献   
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In the present investigation, the influence of retrieval condition on medullary damage in kidneys was assessed. The isolated perfused pig kidney was used to assess initial renal function from multiorgan donors or single organ donors after cold flush and 24 h cold storage preservation with two preservation solutions: Euro-Collins and University of Wisconsin solutions. Kidneys flushed with cold heparinized saline and immediately perfused were used as a control group. Kidneys were perfused for 90 min at 37.5 degrees C and renal perfusion flow rate, glomerular filtration rate, tubular reabsorption of Na+ and lactate dehydrogenase and N-acetyl-beta-D-glucosaminidase excretion were determined. Ischaemia reperfusion impairment was also determined by 1H NMR (proton nuclear magnetic resonance) spectroscopy. Renal function was significantly decreased in experimental groups when compared to the control group, but there was no significant difference between experimental groups after 24 h cold storage. The release of lactate dehydrogenase in the effluent and the urinary excretion of N-acetyl-beta-D-glucosaminidase were not significantly different after 24 h cold storage. The most relevant resonances determined by 1H NMR spectroscopy were citrate, trimethylamine-N-oxide, lactate, acetate and amino acids. Excretion of these markers was significantly different when compared to biochemical markers. A resonance P (Peak) detected particularly in Euro-Collins solution multiorgan donors after 24 h cold storage was identified and well correlated to renal dysfunction. N-acetyl-beta-D-glucosaminidase spectroscopy, which is a non-invasive and non-destructive technique, is more efficient to assess renal damage than conventional histology and biochemical analysis.  相似文献   
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To better understand the impact of incident Parkinson's disease (PD) on the Veteran's Health Administration (VHA) and to develop methods applicable to future epidemiological research, we performed a medical record review study at a tertiary referral VHA medical center. Searching the local data base, we identified 782 veterans with diagnostic codes for PD or secondary parkinsonism (SP) between 1998 and 2000. Based on structured medical record review, a movement disorders specialist confirmed diagnoses for incident parkinsonism cases. Among the 782, 191 incident parkinsonism cases were identified (100 PD, 75 SP, and 16 Parkinson's Plus). Incident PD cases were older at diagnosis (74.5 vs. 70.4 yr; P < 0.05) and more likely to be white (81% vs. 62; P < 0.07) than incident SP cases. Diagnostic codes were insufficient to distinguish between incident PD and SP (positive predictive value, 57% and 39%, respectively), and VHA sources failed to identify 21% of confirmed deaths among the incident PD cohort by November 2004. Although the large number of incident cases identified suggests PD is an important cause of disability among elderly VHA users, observed limitations of VHA sources for identifying incident PD cases and determining their vital status should be considered when designing future studies.  相似文献   
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The anterior, posterior, and transverse bundles of the medial collateral ligaments of fresh cadaveric elbows were painted with a special radiopaque tantalum cyanoacrylic preparation. The extent of each ligament and their origins and insertions were examined with radiography. This study provided radiographic correlation for these important soft tissue structures and an anatomic understanding of elbow fractures with ligament avulsion.  相似文献   
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