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91.
Two laboratories equipped with CAS 200 (Becton Dickinson Image Cytometry Systems, San Jose, CA) instruments participated in this study of variability of DNA analysis of bladder tumor specimens. Formalin fixed paraffin embedded specimens were disaggregated and centrifuged onto microscope slides from ten bladder tumor specimens and two specimens of normal urothelium. Sources of variability considered were Specimen, Slide, Run, Laboratory, and Error. Slides were systematically scanned and 200 cells measured followed by the operator selecting 100 nuclei with abnormal morphology. DNA index (DI) and hyperdiploid fraction (HDF) were calculated from the DNA frequency distributions. For systematic sampling, 92% of the variability was due to Specimen indicating that differences in HDF values between specimens reflect biological differences. With selective sampling, only 67% of the variability in HDF is due to Specimen differences. Other factors, Laboratory, Error, and Laboratory x Specimen interaction each accounted for approximately 10% of the variability. Similarly variability of DI with selective sampling was also higher, and less specimen dependent than systematic sampling. It is important that sampling schemes and selection criteria be carefully documented in order to control variability. Enriched (or selective) sampling for abnormal cells has the potential to increase sensitivity but specimen classification based on these measurements must depend on determination of the frequency of such cells in the total population.  相似文献   
92.
Respiratory aspiration is a serious potential complication of glyphosate-surfactant herbicide intoxication. From October 1, 1992 to June 30, 1996, we performed laryngeal evaluations in 53 cases to investigate the possible pathophysiological mechanism of glyphosate intoxication. There were 36 cases with significant laryngeal injury. The blood WBC count were significantly higher and the hospital stays were significantly longer in patients with laryngeal injury, when compared with patients with no laryngeal injury (Student t-test, P < 0.005). Laryngeal injury was strongly correlated with aspiration pneumonitis (mean 2 = 4.449, P < 0.05). We concluded that laryngeal injury may be the major cause of aspiration that leads to some degree of morbidity and mortality, following concentrated glyphosate-surfactant herbicide intoxication. Laryngeal survey may be indicated in cases of glyphosate-surfactant intoxication, to evaluate the severity of mucosal injury, and to apply adequate supportive management as early as possible to prevent from aspiration complications and even mortality.  相似文献   
93.
The incidence of cerebrovascular diseases with transient or persistent neurologic dysfunction has increased significantly. Although patients with symptomatic carotid artery stenosis clearly benefit from operative therapy, the indication to prophylactic surgery of asymptomatic carotid lesions however is still controversial. Based on data from a recently completed prospective randomized study and on analysis of the literature the indication and results of surgical treatment of asymptomatic stenoses of the carotid arteries are discussed. From 1970 to 1990 a total of 744 uni-or bilateral reconstructions of the internal carotid artery were performed in 631 patients. The perioperative morbidity (permanent neurologic deficiency) and mortality was 1.1% (n = 8) resp. 0.8% (n = 6). During the follow up period up to 18 years another 9 patients suffered from stroke (1.2%). The annual stroke incidence amounted to 0.2%. An important prerequisite for surgery is the so called critical internal carotid artery stenosis, implying reduced cerebral vasomotor reactivity or high embolic risk of an ulcerative plaque. Proper selection of patients (exclusion of multiple concomitant diseases) and an experienced team of vascular surgeons with operative morbidity and mortality below 1-2% validates surgical treatment of asymptomatic carotid artery stenoses.  相似文献   
94.
OBJECTIVES: To evaluate the development of resistance to fosfomycin or fucidic acid in severe infections caused by methicillin-resistant Staphylococcus aureus (MRSA) and to assess the relationship with serum levels of vancomycin METHODS: A retrospective study was performed in patients hospitalized in our intensive care unit during a 3-year period (1993-1995) who were treated for severe MRSA infection with continuous infusion vacomycin and fosfomycin or fucidic acid. We analyzed the development of resistance and serum levels of vancomycin. RESULTS: During this period, only 20 patients received continuous infusion vancomycin plus fucidic acid or fosfomycin. MSRA resistant to fucidic or fosfomycin developed in 9. Vancomycin serum levels were significantly lower in patients who developed resistance to focidic acid or fosfomycin, both during the first 5 days of treatment (16.68 +/- 1.07 micrograms/ml vs. 22.64 +/- 1.05 mg/ml, p < 0.01) and throughout treatment duration (17.29 +/- 1.07 micrograms/ml vs. 21.85 +/- 0.78 microgram/ml, p < 0.01). CONCLUSIONS: Our findings confirm that in spite of continuous vancomycin infusion at an initial rate of 2 g/24 h, Staphylococcus aureus resistance to fosfomycin or fucidic acid an develop during ongoing treatment. Vancomycin levels of at least 20 micrograms/ml should be obtained as rapidly as possible.  相似文献   
95.
Cytokines play an important role in the mechanisms resulting in ultraviolet B-induced immunosuppression. They play a crucial role in the induction of local as well as systemic immunomodulatory events. Ultraviolet B irradiation directly induces the release of cytokines in the epidermis, resulting in complex and diverse interactions on epidermal cells, which results in migration out of the skin and infiltration into the skin of different cell types. Partly because of the interaction of locally produced cytokines with antigen-presenting cells, systemic effects, such as antigen-specific tolerance, can be observed. This review describes the different mechanisms whereby ultraviolet B exposure affects immune functions with special emphasis on the role of T-cell subsets and cytokines.  相似文献   
96.
Corticosterone increases with aging but pregnenolone, dehydroepiandrosterone, and testosterone decrease. The marked decrease in hormones that occurs with aging may contribute to the age-related deficit in learning and memory. Administration of these hormones after training was found to improve long-term memory processing in normal young mice. SAMP8 (P8) mice show an age-related loss of learning and memory for a variety of tasks whereas age-matched control mice of the closely related SAMR1 (R1) strain do not. In this study, we found an age-related decrease in serum testosterone levels of 71% between P8 mice 4 and 12 months of age, but only a 26% decrease between R1 mice of the same ages. The difference between the P8 mice was significant (p < 0.01) and the difference between the R1 mice was not. The decrease in testosterone in 12-month-old P8 mice was not accompanied by gross morphological change in the testes. A SC testosterone implant, sufficient to increase plasma testosterone levels to 414 +/- 25 ng/dl, alleviated impaired learning and memory of a foot shock avoidance task in P8 mice. Castration of 4-month-old P8 mice did not produce a deterioration in learning and memory, indicating that low levels of testosterone per se are not responsible for the impairment seen in 12-month-old P8 mice. This suggests that impaired cognitive functioning of the older P8 mice was due to an interaction of aging and reduced testosterone levels.  相似文献   
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98.
The optimization of a manufacturable self-aligned titanium silicide process is described. In particular, the integrity of the TiSi 2 layer has been studied versus the BPSG reflow conditions. Excellent contact resistance and very low leakage currents have been obtained. The good device parameters obtained with an n+ or n +/p+ gate have demonstrated that the self-aligned process can be integrated in a 0.8-μm double-metal CMOS process  相似文献   
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