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1.
The in vitro activities of povidone iodine, potassium peroxymonosulfate, and dimethyldidecylammonium chloride were investigated against 379 nosocomial isolates of Staphylococcus aureus and Pseudomonas aeruginosa responsible for surgical wound infections in patients operated on between July 1995 and June 2001. Overall, the isolates were inhibited by the antiseptics at concentrations below those used routinely. In spite of increasing resistance to the various antibiotics used to treat surgical wound infections, no significant variation in the susceptibility to antiseptics was demonstrated during this 6-year study. Electronic Publication  相似文献   
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IgE protein and grass-specific IgE antibodies were detected in the supernatants of 7-day cultures of unstimulated and pokeweed mitogen (PWM) stimulated human blood mononuclear cells from non-atopic and grass pollen-sensitive individuals. Significant amounts of IgE protein were detected in culture supernatants of grass-sensitive individuals and, even at lower levels, in those of non-atopic subjects. In contrast, detectable amounts of grass-specific antibodies were found only in the culture supernatants of grass-sensitive subjects. The mean values of total and grass-specific IgE detected in the supernatants of unstimulated and PWM-stimulated cultures did not differ statistically. Time sequence studies showed that IgE concentrations, measured in the 7-day supernatants, were due to a continuous release from the cells of IgE quantities progressively decreasing up to days 7 or 8. Comparison of the IgE protein and IgE antibody found in the 7-day culture supernatants to those released from initial cell pellets by treatment with acid buffer or freezing and thawing, showed that the IgE detected in 7-day supernatants could result, in part, from the release of cytophilic IgE bound to basophil or other cell types and in part also from the release of preformed lymphocyte cytoplasmic IgE into the supernatant fluids during the course of culture. In most non-atopic subjects and in some grass-sensitive patients the preformed IgE accounted virtually for the total IgE detected in the 7-day culture supernatants. However, the increase of IgE above the levels measured in the initial cell pellets, which was found in most grass-sensitive subjects, clearly reflected newly synthesized IgE. Both cycloheximide and puromycin were capable of reducing significantly the IgE concentration in culture supernatants when it was greater than the amount found in the initial cell pellets. The treatment of cells with mitomycin C was also able to decrease significantly the amount of IgE released in the supernatant after day 3 of culture.  相似文献   
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Previous behavioral work using both mechanical and computer-generated visual stimuli has demonstrated that mantids use a computational algorithm to recognize prey similar to that used by some amphibian predators: A stimulus elicits prey capture behavior if it falls within a perceptual envelope defined by five fundamental stimulus parameters: (1) overall size, (2) length of the leading edge, (3) contrast to the background, (4) location in the visual field, and (5) apparent speed. In this study, we recorded simultaneously from both cervical nerve cords of monocular Sphodromantis lineola while they viewed the same visual stimuli successfully used in the behavioral studies. Extracellular recordings showed three consistently proportioned amplitude classes of movement-elicited spikes in each cord and these were repeatedly and reliably identifiable across mantids. Overall, the movement-elicited activity in both cords was dominated by very large spikes suggesting the existence of several large, descending movement-sensitive interneurons projecting both ipsilaterally and contralaterally from the optic lobes. However, only the largest contralateral spikes occurred preferentially to prey-like stimuli, mirrored the behavioral response curves generated by S. lineola to the same visual stimuli, and displayed activity peaks that were correlated with the times at which the mantid emitted predatory strikes. Copyright (R) 2000 S.Karger AG, Basel  相似文献   
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At present, it is not clear whether mesangial proliferation underlies mesangial expansion in diabetic nephropathy. To address this issue and the relationship between heparin's renoprotective and antimitogenic activities, we studied three streptozotocin-induced diabetic rat groups 5 and 12 months after diabetes induction: two groups were administered a modified heparin, each with a different protocol, and two healthy rat groups, one of which was treated with the same heparin, served as controls. Untreated diabetic animals developed clear evidence of nephropathy, namely expansion of the glomerular extracellular matrix, as expressed by glomerular basement membrane thickening, and increased mesangial deposition of type IV collagen. These alterations were prevented/cured by heparin treatment. Kidney sections were processed immunohistochemically for proliferating cell nuclear antigen and smooth muscle alpha-actin which is expressed only by proliferating mesangial cells. The number of proliferating cell nuclear antigen positive nuclei and alpha-actin-positive cells per glomerulus did not differ between groups at both 5 and 12 months. In conclusion, there is no evidence that mesangial proliferation is increased in late experimental diabetic nephropathy, and heparin seems to be renoprotective through mechanisms other than antiproliferation.  相似文献   
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Evaluation of prognostic factors of adenocarcinoma of Vater’s ampulla is still a matter of debate. The aim of this study was to evaluate retrospectively factors that influence early and long-term outcomes in a 20-year single-institution experience on ampullary carcinoma. A total of 94 consecutive patients with ampullary carcinoma or adenoma with severe dysplasia were managed from 1981 to 2002. Among them, 64 underwent pancreatoduodenectomy, and the remaining 30 submitted to surgical (n = 5) or endoscopic (n = 25) palliative treatment. Demographic, clinical, and pathologic data were collected, and a comparison was made between patients who did or did not undergo resection. Standard statistical analyses were carried out in an attempt to establish a correlation between clinical variables, intraoperative and pathologic factors, and survival in patients with resection. A total of 85 (90.4%) patients had potentially resectable lesions due to the extent of the tumor, but only 64 (68%) underwent curative resection. The surgical morbidity rate was 34.3%. Postoperative mortality was 9.3%, with no deaths among the 38 more recently treated patients. Median survivals were 9 and 54 months for nonresected and resected patients, respectively. The overall 5-year survival was 64.4% for patients undergoing pancreatoduodenectomy. Survival was found to be significantly affected by resection, tumor size, tumor grade, and tumor infiltration. Patients with negative lymph nodes show a trend toward longer survival. In a multivariate analysis, only the depth of tumor infiltration influenced patient survival.Pancreatoduodenectomy is the treatment of choice for ampullary carcinoma and adenomas with high-grade dysplasia, with a good chance of long-term survival. Surgical resection remains the most important factor influencing outcome.  相似文献   
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Background Use of laparoscopy for isolated adrenal metastases is controversial. The aims of this study were to characterize patients with isolated adrenal metastases; compare operative characteristics of the laparoscopic adrenalectomy (LA) versus open adrenalectomy (OA) approach; and compare long-term oncological and surgical outcomes. Methods Our adrenal resection database (1995–2006) identified 63 OA and 31 LA cases done for isolated adrenal metastases. Subset analysis was performed for all patients from isolated lung metastases (n = 39) and for all tumors smaller than 4.5 cm (n = 49). Results Overall, local recurrence was 17%, median survival 30 months and 5-year estimated survival 31%. The only independent predictor of survival for all (n = 94) was adrenal tumor size less than 4.5 cm (P = 0.01). When comparing LA with OA, no differences in local recurrence, margin status, disease-free interval or overall survival were observed for the entire group, or for patients with metastases only from lung cancer (n = 39) or for those with tumors smaller than 4.5 cm (n = 49). LA provided significantly shorter operative time (175 vs 208 min, P = 0.04), lower estimated blood loss (EBL) (106 vs 749 cc, P < 0.0001), shorter length of hospital stay (2.8 vs 8.0 days, P < 0.0001) and fewer total complications (P < 0.0001). Conclusions LA is equivalent to OA in terms of margin status, local recurrence, disease-free interval and overall survival. LA for metastatic adrenal lesions is safe, with equivalent long-term oncological outcomes providing the additional benefits of a minimally invasive technique. LA can be recommended as an appropriate initial approach for isolated adrenal metastases.  相似文献   
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OBJECTIVE: To evaluate hypothalamic-pituitary-adrenal (HPA) axis function in patients with recent onset polymyalgia rheumatica (PMR) not previously treated with glucocorticoids; and to detect possible correlations between adrenal hormone levels, interleukin 6 (IL-6), and other acute phase reactants at baseline and during 12 months of glucocorticoid treatment. METHODS: Forty-one PMR patients of both sexes with recent onset disease and healthy sex and age matched controls were enrolled into a longitudinal study. Patients were monitored for serum cortisol, dehydroepiandrosterone sulfate (DHEAS), androstenedione (ASD), and clinical and laboratory measures of disease activity such as C-reactive protein and IL-6 concentrations at baseline and after 1, 3, 6, 9 and 12 months of glucocorticoid treatment. To assess dynamic HPA axis function, serum cortisol and plasma adrenocorticotropic hormone (ACTH) levels were evaluated in another 8 patients with recent onset PMR not treated with glucocorticoid in comparison to controls after challenge with ovine corticotropin releasing hormone (oCRH) test. In addition, serum cortisol and 17-hydroxyprogesterone (17-OHP) levels were evaluated after stimulation with low dose (1 microg) intravenous ACTH. RESULTS: Serum cortisol and ASD levels of all PMR patients at baseline did not differ from controls. During followup, cortisol levels dipped at one and 3 months. Serum DHEAS levels in all patients were significantly lower than in controls at baseline. In female PMR patients a significant correlation was found at baseline between cortisol levels and duration of disease. Serum concentrations of IL-6 at baseline were significantly higher in PMR patients than in controls. During 12 months of glucocorticoid treatment IL-6 levels dropped significantly at one month; thereafter they remained stable and did not increase again despite tapering of the glucocorticoid dose. After oCRH stimulation, a similar cortisol response was found in patients and controls. After ACTH administration, a significant cortisol peak was detected in patients and controls, whereas no significant difference in cortisol area-under-the-curve (AUC) was found between the groups. In contrast, ACTH induced a significantly higher (p < 0.05) peak of 17-OHP and AUC in PMR patients than in controls. CONCLUSION: This study found reduced production of adrenal hormones (cortisol, DHEAS) at baseline in patients with active and untreated PMR. The defect seems mainly related to altered adrenal responsiveness to the ACTH stimulation (i.e., increased 17-OHP), at least in untreated patients. The 12 month glucocorticoid treatment of patients reduced the production of inflammatory mediators (i.e., IL-6) in a stable manner that persisted after glucocorticoids were tapered.  相似文献   
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