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91.
Immunohistochemical localization of laminin in the basement membranes of normal, hyperplastic, and neoplastic human prostate 总被引:2,自引:0,他引:2
A A Sinha D F Gleason M J Wilson N A Staley L T Furcht S L Palm P K Reddy R K Sibley A Martinez-Hernandez 《The Prostate》1989,15(4):299-313
We examined the effects of fixatives and antibody sources on the immunohistologic localization of laminin in normal and cancer-containing human prostates and studied the localization patterns in carcinomas of varying degrees of histologic differentiation. Two different polyclonal antibodies were localized in paraffin-embedded or cryostat sections of fixed (alcohol, formalin, and paraformaldehyde) or unfixed tissue, using the immunofluorescence (IF) or immunoperoxidase (IP) techniques, with positive and negative controls. We found that the IF reactions were more intense in unfixed or alcohol-fixed sections than in paraformaldehyde-fixed specimens. IP reactions were very weak or absent in fixed and paraffin-embedded sections, but pepsin treatment of these sections resulted in more intense and uniform IP reaction products, stronger than in unfixed or ethanol-fixed cryostat sections. With the IP technique, laminin localization was intense and uniform in the basement membranes (BM) of acini, blood vessels, smooth muscle, and nerve fibers in normal prostate, benign hyperplasia (BPH), and well-differentiated carcinomas. The BM of poorly differentiated carcinomas showed widespread absence of laminin reactivity. In normal BPH and well-differentiated tumors, occasional epithelial cells and their surface and acinar lumina had laminin reactivity. However, in higher grade tumors, numerous neoplastic cells had laminin reactivity in cytoplasm, their surface, and secretory material. Some macrophages and neutrophils also contained laminin reactivity, presumably of degraded laminin. In some moderately and poorly differentiated tumors, the BM of small capillaries did not contain laminin. The BM of larger vessels always had laminin reactivity, even in the higher grade tumors. 相似文献
92.
Temporal filtering methods were applied to iodine signal-to-noise ratio (SNR) restoration in intravenous hybrid subtraction digital subtraction angiography (DSA). For equal detected exposure rates hybrid subtraction had approximately 35% of the SNR of temporal subtraction. When matched filtering was applied to a DSA run, the filtered result had approximately two times higher SNR than the peak contrast image in the run. Thus, when matched filtering techniques were applied to the hybrid image sequence, the resultant SNR increased to about 70% of that of temporal subtraction. With an additional factor-of-two increase in exposure rate for the hybrid run, SNR parity with temporal subtraction could be achieved. This compared with a factor-of-nine increase in exposure that would be required if no filtering were performed. Experimental hybrid matched filter results, generated with intravenous canine DSA studies, supported the predictions in SNR performance. 相似文献
93.
Two distinct separation fluoroimmunoassays were developed to determine serum levels of bendazac and its main metabolite 5-hydroxy bendazac for use in early pharmacokinetic studies and for long-term therapeutic drug monitoring should this prove necessary. In both assays fluorescein-labeled analyte was used as tracer and the antibodies were coupled to magnetizable particles. The use of a magnetizable solid phase enabled a simple and rapid separation step and thus a high sample throughput. There was no crossreactivity between the drug and its metabolite in either assay, indicating that highly specific antibodies had been produced. The results from both assays correlated well with serum levels determined by a high performance liquid chromatography method. 相似文献
94.
Objective : To document the nosocomial infection rate in a single neonatal intensive care unit (NICU) in terms of patient workload and device utilization.
Methodology : Nosocomial infections have been identified and documented by the methodology described by the National Nosocomial Infection Surveillance System (NNIS), Centres for Disease Control, Atlanta. In addition, antibiotic usage has been surveyed in the NICU and standardized measures of patient exposure to antibiotics stratified by birthweight and gestational age have been described.
Results : Overall nosocomial infection rates compared favourably with the published NNIS figures at 6.2 infections per 100 admissions or 4.8 per 1000 patient days. Infection rates were significantly higher in lower birthweight groups. Device-related infection rates in each birthweight cohort were also very close to published figures and varied less with birthweight group. Antibiotic exposure averaged 12% of total admission days, less than previously published data.
Conclusions : The NNIS system is applicable to Australian NICU and provides an effective tool for monitoring infection episodes. 相似文献
Methodology : Nosocomial infections have been identified and documented by the methodology described by the National Nosocomial Infection Surveillance System (NNIS), Centres for Disease Control, Atlanta. In addition, antibiotic usage has been surveyed in the NICU and standardized measures of patient exposure to antibiotics stratified by birthweight and gestational age have been described.
Results : Overall nosocomial infection rates compared favourably with the published NNIS figures at 6.2 infections per 100 admissions or 4.8 per 1000 patient days. Infection rates were significantly higher in lower birthweight groups. Device-related infection rates in each birthweight cohort were also very close to published figures and varied less with birthweight group. Antibiotic exposure averaged 12% of total admission days, less than previously published data.
Conclusions : The NNIS system is applicable to Australian NICU and provides an effective tool for monitoring infection episodes. 相似文献
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97.
Thomas P. Thomas M.D. Charles J. Staley M.D. James B. Hammond M.D. 《Digestive diseases and sciences》1968,13(9):842-846
Summary A patient is described with squamous cell carcinoma of the lower third of the esophagus which was complicated by gastric retention and atony simulating mechanical pyloric obstruction. This was due to incarceration of both vagal trunks in the tumor with infiltration of the nerves and, it is presumed, resultant nerve degeneration. The effects of vagal denervation were similar to those of surgical vagotomy. The patient required a gastroenterostomy to reduce gastric retention.Thanks are due to Dr. Emanuel R. Ross, Departments of Pathology and Neurology, Northwestern University Medical School, for interpretation of the histologic sections. The assistance of the Laboratory and Medical Illustration Services is gratefully acknowledged. 相似文献
98.
A national survey of psychiatric social workers in all Canadian hospitals with Psychiatric Residency Training Programs was conducted. Various professional activities and university appointments were considered. Comparisons were made among provinces to determine differences and similarities. The results indicate a large number of similarities. The major part of social workers' professional time is spent in client-centred activity, though some regional differences emerge as to the mode of activity emphasized (e.g. individual or systems). A secondary but clearly evident role was formal and informal teaching. While educational pursuits were requested of social workers, their activities were generally not recognized through academic appointments. Research appeared to be a low priority. The lack of academic recognition for teaching and the lack of research productivity were viewed as external and internal aspects of an identity issue that social work needs to address. 相似文献
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