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941.
C M Mond D B Walters R S Stricoff E M Prescott A T Prokopetz 《American Industrial Hygiene Association journal》1987,48(10):823-829
A human factors engineering analysis of a chemical containment laboratory was performed to develop appropriate standards for future laboratory design. In order to perform this evaluation, a state-of-the-art facility was studied in depth. Measurements and observations were made of key operating areas. In addition, technicians were observed and interviewed as they performed various tasks. Compiled data were compared to existing ergonomic standards. The occupational implications of instituting ergonomically developed laboratory design standards are as follows: increased worker health, safety and productivity, improved work quality and reduced stress. 相似文献
942.
The ganglioside composition of human melanoma was analyzed in five sets of tumor specimens obtained directly from surgery, from the autologous tissue culture cell lines, and from the autologous cell lines grown in athymic nude mice. Total gangliosides of these 15 melanoma specimens were isolated and purified, and the amount of each component ganglioside was analyzed by thin-layer chromatography and a thin-layer chromatography scanner. The ganglioside composition of the five surgical melanoma specimens clearly exhibited different patterns from each other. Moreover, none of the autologous cultured melanomas possessed the same ganglioside composition as their original biopsied tumors. However, when these melanoma cell lines were transplanted into nude mice, the ganglioside composition was converted back to the same ganglioside pattern as in the original surgical specimens. The results support the view that changes in the ganglioside composition of melanoma during in vitro growth are caused by the culture environment rather than by selection of melanoma cells with a particular genotype. Reestablishment of the original ganglioside patterns after passage in nude mice provides clear evidence that in vivo expression of gangliosides is a conserved and stable function specified by the human melanoma cells. 相似文献
943.
The intensity and degree of heterogeneous epithelial marker expression were evaluated immunohistochemically in 29 mucosal biopsy specimens from 7 ulcerative colitis (UC) patients with dysplasia. Biopsy specimens from UC patients with mild (n = 7) or severe (n = 6) inflammation and from histologically normal samples (n = 7) served as controls. HLA-DR showed heterogeneous epithelial expression in all lesions with high grade dysplasia and in 6 of 8 with low grade dysplasia. SC was heterogeneous stained in 17 of 21 lesions with high grade dysplasia and in all but two lesions with low grade dysplasia. In histologically normal mucosa, SC was homogeneously expressed and epithelial DR was virtually absent. In mildly inflamed UC lesions, SC exhibited patchy distribution in only one sample and DR in two, whereas both SC and DR showed a slight degree of heterogeneous expression in all lesions with severe inflammation. Moreover, the overall intensity of SC staining tended to decrease with increasing degree of inflammation, whereas the opposite was seen for DR. Decreased SC and increased DR expression thus seemed to be related to intensified inflammatory activity, whereas heterogeneous expression of these markers was significantly more related to dysplasia. 相似文献
944.
A 43-year-old alcoholic presented in coma with ketoacidosis, after three days of nausea and feeling generally unwell, which had been preceded by a prolonged three-week period of heavy alcohol consumption with poor dietary intake. The acidosis responded rapidly to intravenous dextrose. This is the first Scottish report of a case of alcoholic ketoacidosis. 相似文献
945.
F. Lesoin M. Rousseaux N. Bouasakao L. Villette C. E. Thomas A. Cama M. Jomin 《Acta neurochirurgica》1986,81(3-4):118-124
Summary The authors report 165 cases of thoraco-lumbar lesions with neurological dysfunction. All the patient were operated. They analyze the neurological and mechanical results and indicate the use of different osteosynthesis apparatus according to the type and level of lesions.Harrington's rods seem to give more precise repositioning while Roy Camille's plates give more stability. When the posterior wall of the spinal canal is intact, Kempf's compression rods can be used.Thoraxic spine injuries seem to be an indication for Harrington's rods, while lumbar injuries seem to call for Camille's plates. 相似文献
946.
947.
An experimental model has been developed for the study of combined effects of partial body irradiation (PBI) and graft-versus-host disease (GVHD) in which irradiation is delivered to the thorax 24 hr prior to induction of GVHD in hybrid mice by the injection of parental lymphoid cells. In mice irradiated to 1000 cGy or exposed to low doses of allogeneic lymphoid cells (20 X 10(6)), survival was 100% at 250 days. In contrast, combination of the two treatments, GVHD and PBI, resulted in a mortality of 83% and a mean survival time of 29 days, indicating synergy between GVHD and PBI. From histological studies of the lung it appeared that about 40% of the deaths occurring after combined GVHD/PBR treatment might be attributable to pneumonia. The cause of death in the remaining mice receiving combined treatment is not known. Mice receiving combined PBI/lymphoid cell treatment develop a characteristic skin lesion that is not seen in nonirradiated mice and is confined to the irradiated area. The effect of preinduction PBR on the timing and severity of GVHD is similar to that which would be produced by an increase in the number of effector cells. 相似文献
948.
This study focuses on obtaining more information about the site of anastomosis, with three-dimensional examination using methylmethacrylate resin (Mercox) corrosion casts. Seventy microvascular anastomoses were performed in Wistar albino rats, divided into two groups before sacrifice. In Group 1 (35), Mercox was injected into the vessels, whereas in Group 2 (35), the tissues were prepared without injecting Mercox. Both groups were compared under the scanning electron microscope (SEM). The SEM preparation in Group 1 was simple, easy, and artifacts were significantly minimized. The anastomotic site could be well appreciated in three-dimensional views. Clear negative imprints of the endothelial surface were achieved without any breakage in the Mercox corrosion cast, and it can be reliably used in the evaluation of small vessel anastomosis. 相似文献
949.
Do-not-resuscitate orders for critically ill patients in the hospital. How are they used and what is their impact? 总被引:9,自引:0,他引:9
We studied compliance with do-not-resuscitate (DNR) orders at a university hospital where a DNR protocol has existed since 1979. Documentation of DNR status in patient progress notes and chart orders increased through 1983. During a 12-month period (March 1983 through April 1984), we studied in detail the medical records of 521 patients who had a cardiopulmonary arrest in the hospital. Seventy-five percent (389 of 521) of these patients were designated DNR. Patients who were designated DNR were significantly more likely to be older, to have malignancy or an abnormal mental status, and to be less likely to have acute myocardial infarction, stroke, or chronic obstructive pulmonary disease than patients in whom resuscitation was attempted. Eighty-six percent of families, but only 22% of patients, were involved in the decision to designate a patient DNR. The decision to designate a patient DNR occurred late in the course of a patient's illness, often when the patient was in coma. For 28% of patients, some form of medical care was withdrawn or withheld after they were designated DNR. These data suggest that use of the DNR protocol requires changes if patients are to participate in the decision not to undergo cardiopulmonary resuscitation. 相似文献
950.