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981.
982.
BACKGROUND: Our aim was to determine the frequency, survival and symptomatic local recurrence rate of patients with a positive proximal resection margin in a series of patients having a resection for carcinoma of the oesophagus or stomach. METHODS: A retrospective study of pathology reports and case notes. Survival and data on local recurrence were obtained from the patient or general practitioner. RESULTS: Ten (11.5%) of 87 patients having a gastric or oesophageal resection for carcinoma had a positive proximal resection margin. All 10 patients underwent a palliative resection for late-stage disease. Nine were dead at an average 8.3 months (range 2-20 months) post-resection and one patient remains alive at 9 months. Only one of these 10 patients had evidence of a local recurrence with recurrent dysphagia prior to death at 11 months. CONCLUSION: A high incidence of a positive proximal resection margin was found. This occurred in patients who underwent a palliative resection for late-stage disease, most of whom died before local recurrence became a problem. For patients recognized as having late-stage disease, surgery for symptom palliation need not be aggressive (such as to include a thoracotomy) because achieving microscopic clearance is unlikely to affect the long-term outcome.  相似文献   
983.
Purpurogallin (PPG) in an active cytoprotector found in certain oak barks. We have shown that PPG prolongs the survival of cultured cardiocytes from rats and rabbits against different oxidants better than do antioxidants such as Trolox (a hydrophilic analogue of vitamin E) in a morphometric assay system. First, we verified by X-ray crystallography that PPG is a bicyclic molecule comprising a phenolic ring fused with a seven-membered ring in a highly planar conformation. In analogues of PPG wherein the two double bonds in the seven membered ring of the parent molecule are saturated or where the four OH groups of the parent compound are substituted by four OCH3 groups, the derivatives are less planar and less protective of the human cells than native PPG. Second, PPG in a concentration-dependent manner protected myocytes and endothelial cells of humans against oxyradicals generated with any one of the following oxyradical generators: (a) xanthine oxidase plus hypoxanthine, (b) menadione, or (c) paraquat. In each case, PPG was more cytoprotective than comparative antioxidants. Also, PPG protected erythrocytes against peroxyl radicals better than the two PPG derivatives mentioned. Third, the cytoprotective action of PPG detected in vitro was accompanied by declines of malondialdehyde. Finally, we observed that PPG chelated ferrous ions and, therefore, can suppress the formation of radicals in the Fenton reaction. Thus, PPG with its molecular architecture and presumably its affinity for ferrous ions protects multiple types of cardiovascular cells against oxyradicals.  相似文献   
984.
OBJECTIVES: To generate a recombinant fusion protein (FP) based on the endotoxin-binding domain of bactericidal/permeability-increasing protein (BPI) and the constant domain of IgG and to test its ability to inhibit lipopolysaccharide (LPS)-induced macrophage tumor necrosis factor alpha (TNF-alpha) secretion. DESIGN: A murine macrophage cell line, RAW 264.7, was transfected with a BPI-IgG FP before incubation with LPS. The amount of LPS-induced TNF-alpha protein secreted was measured and compared with that secreted by cells transfected with a control construct. SETTING: Basic science research laboratory. MAIN OUTCOME MEASURES: Secreted TNF-alpha protein concentration. RESULTS: After transfection, RAW 264.7-cell FP expression was detected in cell lysates and supernatants. At each LPS dose tested, cells transfected with the FP gene secreted less TNF-alpha than did cells transfected with a control construct. CONCLUSIONS: The FP possesses substantial antiendotoxin activity, as delineated by inhibition of LPS-induced TNF-alpha secretion by murine macrophages transfected with the fusion gene construct. In the future, such FP may be used as a clinical reagent to reduce the morbidity and mortality associated with serious gram-negative bacterial infections in surgical patients.  相似文献   
985.
The literature indicates that sire breed of calf influences beef calf performance. However, there is little information concerning sire breed of calf effects on reproduction in beef cows. In this experiment, Angus (A), Brahman (B), or Tuli (T) bulls were bred to 136 Brahman (B) cows to examine sire breed of calf influence on peripartum hormone profiles and the length of postpartum anestrus. Cows were bled from 7 d prepartum to 28 d postpartum to determine peripartum hormone concentrations. Cows carrying AB calves had greater (P < 0.05) prepartum estradiol-17 beta concentrations than did cows carrying BB and TB calves. Prepartum and postpartum progesterone concentrations did not differ between cows with AB, BB, and TB calves. Cows with TB calves had lower (P < 0.01) 13,14-dihydro-15-keto-prostaglandin F2 alpha (PGFM) concentrations than did cows with AB and BB calves during the early postpartum period. Adjusting for birth weight removed the sire breed of calf effect on postpartum PGFM concentrations, but not prepartum estradiol-17 beta. Postpartum anestrus was shorter (P < 0.05) for cows nursing BB calves (84 +/- 6 d) than for cows nursing AB (101 +/- 6 d) or TB calves (110 +/- 7 d). Adjustment for estradiol or PGFM concentrations did not reduce sire breed of calf effects on the length of postpartum anestrus. Further work is heeded to determine how calf genotype may modulate the postpartum reproductive function of the dam.  相似文献   
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The present study was performed to investigate left ventricular diastolic (LVD) function in hypertensive patients with unstable angina. Three groups of 17 patients each were studied. Group 1 consisted of hypertensives with unstable angina (HTU); group 2, normotensives with unstable angina (NTU); and group 3, untreated, uncomplicated hypertensives (HT). The LVD function was assessed echocardiographically by transmitral valve Doppler flow to measure the ratio between the early diastolic filling (E) and the atrial contraction phase (A). An E/A ratio of < 1 was suggestive of LVD dysfunction. Left ventricular mass (LVM), from an M-mode echocardiogram using the Penn-Cube formula, was corrected to body surface area (LVM/S) using a standard nomogram. Data are represented as median values and analyzed by Mann-Whitney test. P was significant at < .05. The HTU group had an E/A ratio of 0.8, and the NTU and HT groups had ratios of 1.17 and 1.1, respectively. There was significant diastolic dysfunction in the HTU group compared with the NTU and HT groups (P = .037 and .049, respectively). Although the LVM/S was significantly higher in the HTU group when compared with the HT group (110.6 and 96.9, respectively, P = .017), there was no significant difference between the HTU and NTU groups (123.1), P = .67. Hypertensive patients with unstable angina have significant LVD dysfunction that seems to be independent of LVM and ischemia. This may be attributable to increased stiffness of the left ventricle or structural left ventricular abnormalities.  相似文献   
990.
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