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11.
Retinal pigment epithelium cells can influence endothelial cell plasminogen activators 总被引:2,自引:0,他引:2
J Moisseiev J A Jerdan K Dyer A Maglione B M Glaser 《Investigative ophthalmology & visual science》1990,31(6):1070-1078
Endothelial cells from both human retinal microvessels (HME) and fetal bovine aortic endothelium (FBAE) were grown in aggregate cultures alone, or with either retinal pigment epithelium (RPE) cells or fibroblasts. The levels of plasminogen activator (PA) and plasminogen activator inhibitor (PAI) in the conditioned media of the various aggregate types were measured. High PA levels were detected in the conditioned medium of pure endothelial cell aggregates (equal to 140% and 124% of urokinase control for HME and FBAE, respectively), and high PAI levels were associated with pure RPE aggregates (inhibiting 93% of the urokinase control). The conditioned medium of pure fibroblast aggregates had very low levels of either PA or PAI. When RPE cells were aggregated with FBAE or HME cells into mixed (heterogenous) aggregates, the PA measured in the conditioned medium was equal to 22% and 30% of the urokinase control, respectively. The PA level in the conditioned medium of mixed fibroblast-FBAE cell aggregates was higher, 104% of the control, and the difference was statistically significant (P less than 0.001). Co-incubation of pure RPE aggregates with pure FBAE aggregates or with pure HME aggregates resulted in PA activity in the conditioned medium that was equal to 110% and 96% of the control, respectively. The PA level found when pure FBAE cell aggregates were co-incubated with pure fibroblast aggregates was higher, 134% of the control, and the difference was statistically significant (P less than 0.001). Our results indicate that RPE cells can reduce endothelial cell PA, probably through both direct contact between the cells and PAI production. Fibroblasts did not have this influence on endothelial cell PA. 相似文献
12.
Riegel Barbara Carlson Beverly Glaser Dale Romero Tomas 《Quality of life research》2003,12(6):689-698
Hispanics are a growing ethnic minority in the United States and one at significant risk for heart failure. Health-related quality of life (HRQL) is poor in individuals with heart failure, especially during and immediately following hospitalization. No prior research into the HRQL of Hispanics with heart failure was located. A sample of 80 individuals with heart failure, evenly divided by primary language and matched on functional status using the New York Heart Association classification system and age, was studied for 6 months following hospital discharge. Data on HRQL were collected using Spanish and English versions of the Minnesota Living with Heart Failure Questionnaire. Scores improved over time in both groups but significantly more so in the Hispanics when compared to the non-Hispanics. Group differences in HRQL could not be explained by demographics, clinical characteristics, treatment received, perceived support, or instrument response characteristics. Further exploration of this naturally occurring phenomenon may provide insight into how HRQL can be improved in the general heart failure population. 相似文献
13.
Although Ga-67 has been used extensively in imaging many different conditions, much is yet unknown about the mechanisms by which gallium concentrates preferentially in tissues such as the liver. This paper reports three patients with markedly diminished hepatic uptake of gallium. The cases are examined in light of published data demonstrating such factors as transferrin levels, radiation, and chemotherapeutic agents as altering the hepatic uptake of gallium. Of the many factors believed to influence the biodistribution of gallium, none can definitively account for the lack of hepatic uptake in these patients. 相似文献
14.
15.
S McShane L Glaser E R Greer J Houtz M F Tong M C Diamond 《Experimental neurology》1988,99(2):353-361
Previous studies on human cortical area 39 suggested that neuron:glial ratios differed between the sexes. These findings were the inspiration for the present investigation which dealt with neuronal and glial counts in area 39 in the male and female rat cerebral cortex. Transverse, celloidin or frozen sections, were cut from male and female brains (respectively) from 90-day-old Long-Evans rats. Neurons and glia were counted on enlarged photographs of stained sections, including area 39, with 35-mm Kodak Panatomic-X film using a Zeiss photomicroscope (X400). Five-by-three-inch prints were taped together in sequence to yield a 640X enlarged "montage" of area 39. Five cell types were differentiated with reference to a standard: neurons, astrocytes, oligodendrocytes, "dark astrocytes," and unidentified glia. The data were analyzed with a two-way analysis of variance (ANOVA: five cell types by two hemispheres). Student's t test and a paired t test were used when appropriate. The neuron:glial ratios in the male rats were consistently higher than those in the females in both hemispheres. The male right side had 12% (P less than 0.05) more neurons than the left; the female had 13% (P less than 0.05) more neurons on the left than the right. Similar, but not identical, asymmetrical patterns were seen with the glial cells. 相似文献
16.
F. Glaser W. Knopp Prof. Dr. G. Muhr 《Archives of orthopaedic and trauma surgery》1988,107(4):253-255
Summary Postoperative hematoma formation must be treated as a potential infection. One fourth of all postoperative hematomas are already contaminated. Ultrasonographical examination is an effective method for early recognition of such postoperative hematomas. Ultrasonic diagnosis on a routine basis is not necessary, but it should be carried out as soon as clinical symptoms appear. Our postoperative late results with only one early and one late infection after 100 postoperative treatments of the hip joint and femoral shaft emphasize the importance of early diagnosis of hematomas.
Zusammenfassung Die drohende Infektion im postoperativen Verlauf nach Osteosynthesen bereitet diagnostische Probleme, da keine objektiven Kriterien vorhanden sind. Das postoperative Hämatom ist als eine drohende Infektion zu beurteilen. 1/4 aller postoperativen Hämatome sind bereits kontaminiert. Die Ultraschalluntersuchung ist eine wirksame diagnostische Hilfe zur frühzeitigen Erkennung der drohenden Infektion bei postoperativen Hämatomen. Sie muß sicherlich nicht routinemäßig, bei klinischem Verdacht aber frühzeitig durchgeführt werden. Das postoperative Spätergebnis mit lediglich einem Frühund Spätinfekt bei 100 operativen Eingriffen am Hüftgelenk und Oberschenkelschaft belegen die Bedeutung der frühzeitigen Hämatomdiagnostik.相似文献
17.
J. Sattler W. Lorenz D. Schr?der A. Klingler J. Klag K. Glaser R. Dennhardt 《Inflammation research》1992,36(Z2):C155-C161
The effectiveness of an H1
–+H2-prophylaxis against perioperative acute pseudoallergic reactions in which histamine is involved, and against postoperative complications the incidence of which may be increased by these reactions, was the central problem of a randomized trial in 162 aged patients during elective conventional cholecystectomy. As main endpoint it was planned to use the systemic histamine release reaction, as it already had been defined for the conscious and anaesthetized human subject. However, it had to be reassessed and redefined for the intraoperative period after improvement of the plasma histamine assay and new findings about stress-induced histamine release and the kinetics of histamine release during certain phases of operation.Intraoperative release is, at present, defined solely as an increase of plasma histamine values after a particular action (phase of operation). It includes criteria concerning plasma histamine changes either in comparison to the base value before surgery or to the preceding value before the last surgical action. Histamine elevations must exceed the last value by more than 3 standard deviations of the analytical error (i.e. 200% if value <0.25 ng/ml=" and=" 40%=" above).=" basic=" requirements=" for=" the=" histamine=" assay=" (quality=" control),=" correct=" sample=" taking=" and=" appropriate=" preparation=" have=" to=" be=" fulfilled=" over=" the=" whole=" trial=" period.=" when=" these=" criteria=" were=" applied=" to=" the=" 162=" patients=" an=" overall=" incidence=" of=" histamine=" release=" during=" cholecystectomy=" of=" 55.6%=" was=" found=" with=" 9.7–20%=" during=" an=" individual=" phase=" of=" operation.=" the=" data=" of=" this=" study,=" performed=" under=" routine=" conditions,=" with=" a=" sufficient=" number=" of=" patients=" with=" elevated=" risk=" and=" event=" controlled=" plasma=" histamine=" values,=" lead=" to=" a=" better=" understanding=" of=" intraoperative=" histamine=" release,=" its=" incidence=" and=">0.25> 相似文献
18.
J Tschmelitsch K Glaser C Schwarz G Judmair E Bodner 《Journal of ultrasound in medicine》1992,11(4):149-153
The ability of endosonography (ES) to detect local recurrence after "curative" surgery for rectal cancer was investigated in 65 patients. Fifteen patients developed local recurrence. All of these 15 patients had ES evidence of recurrence; in four cases recurrence was detected by ES alone. Ten of the 15 patients with local failure underwent reoperation. Four patients were candidates for reoperation for cure. Three patients with radical reoperation belonged to the group in which recurrence was detected by ES alone. ES is able to detect small tumors before there is evidence of recurrence in other available forms of examination. 相似文献
19.
New methods for the detection of ECG and EOG artefacts in the EEG are introduced, which can also be used for the evaluation
of the quality of the elimination procedure. These algorithms are based on the estimation of the power or coherence spectrum
by means of FFT. The advantage of this method is that the EEG spectrum is monitored by the test algorithm. The spectrum will
be plotted if no influence of the ECG and EOG can be found. On the other hand, if artefacts are detected the correction of
the EEG time series will be carried out and the spectrum of the corrected EEG time series will be plotted after repeated monitoring
by the test algorithm. 相似文献
20.
Long-term ultraviolet-light (UV) exposure of human skin epidermis is associated with an increased risk for the development of skin cancers, such as melanoma, basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). UV radiation not only induces DNA damage in epidermal cells, it also interferes with skin homeostasis, which is maintained by a unique distribution pattern of apoptosis-inducing and -preventing molecules. If the DNA damage is not repaired or the damaged cells are not eliminated by apoptosis, the consequence can be cell transformation, uncontrolled proliferation and eventually skin tumor formation. An important "repair" gene is the p53 suppressor gene. Excessive UV exposure can mutate the p53 gene leading to the loss of its repair function and thus apoptosis resistance of the DNA-damaged cell. For BCC formation an additional pathway has been identified. Mutation of genes of the Hedgehog signaling pathway evokes the downregulation of apoptotic genes and upregulation of anti-apoptotic genes preventing the elimination of damaged cells. In addition, BCC and SCC strongly express the apoptosis-inducing Fas-ligand (FasL) which may help the tumor to escape the attack of immune effector cells. Silencing the genes involved in tumor formation by RNA interference might become a promising new approach to treat skin tumors. 相似文献