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51.
Kurt W. Pontasch John Cairns Jr. 《Archives of environmental contamination and toxicology》1991,20(1):103-112
A study was conducted to determine if contaminant-induced changes in macroinvertebrate communities in laboratory stream microcosms could be used to predict responses of these organisms in a natural stream receiving the same contaminant. Test organisms were transferred to the artificial streams in rock-filled containers previously colonized for 30 days upstream of the effluent outfall. The microcosms were exposed for 20 days to concentrations of the effluent that reflected those at field sites where macroinvertebrates were collected.The stream microcosms maintained most taxa at or above initial densities. However, adult insect emergence from the microcosms must be monitored during such studies. The relative sensitivity of species and the effluent concentrations causing changes in insect density were similar in the microcosms and the field. Mayflies were the most sensitive group, and densities in the microcosms were significantly (P 0.05) reduced at 1.0% or 10.0% effluent concentration depending on species. Conversely, chironomids densities were increased by exposure to the effluent. The mayflies responded at lower concentrations than acute tests withDaphnia magna would have predicted. 相似文献
52.
Kurt Freund MD DSc Robin Watson MEd Robert Dickey MD 《Sexual abuse : a journal of research and treatment》1991,4(1):93-105
The rationale for dividing the clinical spectrum of DSM-III-R male heterosexual gender identity disorder into three types was examined. The DSM-III-R category of fetishism for female attire, was included in the analysis. There were 266 male participants divided into three groups: 172 fetishists for female attire or gender identity patients, 52 androphiles, and 42 gynephiles. A 16 item questionnaire was used to examine the groups. A three factor scale ("Fetishism", "Gender Dysphoria" and "Androphilia") was derived from the questionnaire. Only the Gender Dysphoria Factor Scale successfully differentiated between all four conditions, supporting the notion that the three types of gender identity disorder represent a continuum of degree of severity of gender dysphoria. Defining two of the three types of gender identity disorder in terms of the patients' self-reports on fetishism, as DSM-III-R does, is therefore unnecessary. 相似文献
53.
Kurt Schneider Melvin R. Kinlow A. N. Galloway Don L. Ferro 《Child & youth care forum》1982,11(4):298-311
The effects of implementing the Teaching-Family Model in two community-based group homes were assessed through a series of pre-post measures. Data analysis indicates substantial positive change in youth social skills, program quality, youth and staff satisfaction levels, social climate, and staff accountability for care of the children.Requests for reprints, samples of the Staff Accountability Scale, and other forms or the questionnaires in this study should be addressed to Kurt Scheider at The Maryville Academy, 1150 North River Road, Des Plaines, IL 60016 相似文献
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55.
Petra Heinm?ller Christof Gross Kurt Beyser Claudia Schmidtgen Gerd Maass Michele Pedrocchi Josef Rüschoff 《Clinical cancer research》2003,9(14):5238-5243
PURPOSE: For the first time a large number (563) of non-small cell lung cancer (NSCLC) samples was used to compare three different technologies for the assessment of HER2 status. Fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) were used for tumor tissue samples, and ELISA for serum samples. The results were compared with other tumor entities, mainly breast. EXPERIMENTAL DESIGN: Samples (563) from patients suffering from primary advanced or metastatic NSCLC were evaluated. RESULTS: HER2 overexpression was demonstrated using IHC in 20% (83 of 410) of the specimens, whereas 2% (7 of 378) were positive by FISH and 6% (31 of 511) showed elevated serum HER2 levels (>15 ng/ml) by ELISA. Sixty-six specimens were positive by IHC only and 13 by ELISA only, whereas none of the specimens was positive only by FISH. Concordance between all of the techniques was seen for only 3 specimens. Of 7 IHC 3+ specimens, 4 showed gene amplification by FISH, and 3 were positive by ELISA (>15 ng/ml), whereas of 76 IHC 2+ cases only 2 were amplified by FISH, and 4 were positive by ELISA. HER2 positivity by at least one of the three techniques was most common in adenocarcinomas, at 29% (42 of 143). CONCLUSION: Gene amplification and HER2 protein overexpression at the 3+ level appear to be uncommon in NSCLC. The concordance between FISH and IHC 3+ disease was good in this study, in addition, ELISA would have detected several patients without IHC/FISH-positive disease. 相似文献
56.
Ulrike Heider Corinna Langelotz Christian Jakob Ivana Zavrski Claudia Fleissner Jan Eucker Kurt Possinger Lorenz C Hofbauer Orhan Sezer 《Clinical cancer research》2003,9(4):1436-1440
PURPOSE: Increased bone resorption is a hallmark of multiple myeloma and is attributable to osteoclast activation. Recent studies showed that the receptor activator of nuclear factor kappaB ligand (RANKL) is the key mediator of osteoclastogenesis and plays a crucial role in bone destruction in malignant bone disease. We found that human myeloma cells express RANKL and analyzed the association of the RANKL expression with the presence of osteolytic bone disease in patients with multiple myeloma. EXPERIMENTAL DESIGN: Flow cytometry was performed on bone marrow samples derived from controls and multiple myeloma patients with or without osteolytic bone lesions on conventional radiography. Plasma cells were identified as CD38++/CD138+ cells. The level of RANKL expression on the surface of bone marrow plasma cells was correlated with the bone status of the patients. RESULTS: The bone marrow plasma cells from controls showed no or only a weak surface expression of RANKL, and the median mean fluorescence index (MFI) was 6. In contrast, expression of RANKL could be detected on bone marrow plasma cells from all of the patients with multiple myeloma, and median MFI was 47. The difference in MFI for RANKL expression of bone marrow plasma cells from controls and myeloma patients was highly significant (P < 0.0005). Myeloma patients with osteolytic bone lesions showed a significantly higher expression of RANKL (median MFI = 60; range, 16-2494) compared with patients without osteolysis (median MFI = 16; range, 6-229; P < 0.0005). CONCLUSIONS: These results show for the first time that the level of RANKL expression by myeloma cells correlates significantly with osteolytic bone disease. 相似文献
57.
58.
BACKGROUND: Six patients known to have inoperable esophageal carcinoma presented with stridor due to both malignant tracheal stenosis (n = 6) and bilateral vocal cord paralysis. Two patients also had respiratory-digestive fistula. METHODS: Patency was restored by endotracheal stenting plus unilateral cordectomy. Four patients had immediate relief. Two patients required enlargement of the cord incision. One of them declined reoperation and underwent tracheotomy. RESULTS: Stent function was uneventful. There was no dislodgement or mucous impaction. Fistula seal was complete. There was no aspiration through the new-shaped glottic orifice. Peak expiratory flow increased from 24.4% +/- 9.7% predicted normal before to 40.5% +/- 13.7% after the procedure, whereas the dyspnea score decreased from 74.2 +/- 12.7 to 24.2 +/- 14.0. CONCLUSIONS: Restoration of airway continuity in serial laryngotracheal stenoses using a combined approach is a feasible technique in end-stage cancer patients. It effectively relieves respiratory distress and ensures voice preservation. In addition, it may avoid the risks of tracheotomy. 相似文献
59.
We have quantified in vitro the influence of the facemask on the amount of drug delivered (e.g., inhaled mass) by jet nebulizer and pressurized metered dose inhaler (pMDI) valved holding chamber (VHC) combinations (non-detergent-coated and detergent-coated). Pediatric breathing patterns were used with a breathing simulator, which was connected to a face onto which each device was positioned. An inhaled mass filter interposed between the simulator and the face captured the aerosolized drug. Budesonide inhalation suspension (0.25 mg) was used with the jet nebulizers and fluticasone propionate (220 microg) pMDI with the VHCs. Maximal drug delivery was measured using constant flow through each device. Breathing pattern effects were assessed for sealed devices (no leaks) and with facemasks (possible leaks at the facemask). Inhaled mass from both nebulizers and pMDI VHCs was affected by breathing pattern, but compared to nebulizers the pMDI VHCs were significantly more variable and sensitive to several factors. The influence of VHC conditioning combined with effects of breathing pattern resulted in the inhaled mass ranging from 0.7 +/- 0.5 to 53.3 +/- 6.2%. Nebulizers were less variable (9.6 +/- 0.7 to 24.3 +/- 3.1%). Detergent coating of VHC markedly increased the inhaled mass and reproducibility of drug delivery (27.2 +/- 1.4 to 53.3 +/- 6.2%) for pMDI VHC combinations, but these effects were lost in the presence of facemasks. Using pediatric patterns of breathing, nebulizer/facemask combinations delivered 4.1 +/- 0.8 to 19.3 +/- 2.3% of the label dose while pMDI and detergent-coated VHC delivered 4.0 +/- 1.6 to 28.6 +/- 2.5%. Facemask seal is a key factor in drug delivery. Leaks around the facemask reduce drug delivery and for pMDI VHCs can negate effects of detergent coating. 相似文献
60.
Anne Marie Asemissen Carmen Scheibenbogen Anne Letsch Kristoffer Hellstrand Fredrik Thorén Kurt Gehlsen Alexander Schmittel Eckhard Thiel Ulrich Keilholz 《Clinical cancer research》2005,11(1):290-297
PURPOSE: Preclinical investigations suggest that histamine dihydrochloride (HDC) protects T cells and natural killer cells from inhibition by monocyte-derived reactive oxygen metabolites and synergizes with interleukin (IL) 2 in inducing T-cell activation. Here, we investigate whether this mechanism is operational in patients with melanoma treated with HDC as an adjunct to IL-2. EXPERIMENTAL DESIGN: Melanoma patients having liver metastases were treated with IL-2 with or without HDC within a randomized, multicenter, phase III trial. The effect of HDC on type 1 and type 2 T-cell cytokine production was investigated in peripheral blood samples from 19 patients with the use of intracellular cytokine flow cytometry. Melanoma-specific T-cell responses were analyzed in eight HLA-A2-positive patients. RESULTS: Frequencies of CD3+ T cells producing IFN-gamma (type 1 T cells) in response to phorbol myristate acetate/ionomycin increased (median, 1.8-fold) in patients receiving IL-2 plus HDC but not in those receiving IL-2 alone (P < 0.01 for comparison between arms). In contrast, the number of IL-13-producing type 2 T cells that increased in patients after treatment with IL-2 was not modulated by HDC. Melanoma- and tyrosinase-specific IFN-gamma and IL-13-producing T cells were detected in two of four HLA-A2-positive patients with melanoma following treatment with HDC + IL-2. CONCLUSIONS: Treatment of patients with stage IV melanoma with HDC in combination with IL-2 increases type 1 T-cell responses and may promote induction of melanoma-specific T cells. These effects are of relevance for tumor immunotherapy and provide a potential mechanism for the clinical efficacy of HDC added to IL-2. 相似文献