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991.
M Wakamiya EA Lindsay JA Rivera-Pérez A Baldini RR Behringer 《Canadian Metallurgical Quarterly》1998,7(12):1835-1840
Gscl encodes a Goosecoid-related homeodomain protein that is expressed during mouse embryogenesis. In situ hybridization and immunohistochemistry studies show that Gscl is expressed in the pons region of the developing central nervous system and primordial germ cells. Gscl expression is also detected in a subset of adult tissues, including brain, eye, thymus, thyroid region, stomach, bladder and testis. Gscl is located within a region of the mouse genome that is syntenic with the region commonly deleted in DiGeorge and velocardiofacial syndrome (DGS/VCFS) patients. DGS/VCFS patients have craniofacial abnormalities, cardiac outflow defects and hypoplasia of the parathyroid gland and thymus due to haploinsufficiency of a gene or genes located within the deleted region. Thus, the genomic location of Gscl and its expression in a subset of the tissues affected in DGS/VCFS patients suggest that Gscl may contribute to the pathogenesis of DGS/VCFS. To determine the role of Gscl during mouse embryogenesis and in DGS/VCFS, we have deleted Gscl by gene targeting in mouse embryonic stem cells. Both Gscl heterozygous and Gscl null mice were normal and fertile, suggesting that Gscl is not a major factor in DGS/VCFS. Interestingly, expression of the adjacent Es2 gene in the pons region of Gscl null fetuses was absent, suggesting that mutations within the DGS/VCFS region can influence expression of adjacent genes. In addition, embryos that lacked both Gscl and the related Gsc gene appeared normal. These studies represent the first functional analysis of a DGS/VCFS candidate gene in vivo. These Gscl null mice will be an important genetic resource for crosses with other mouse models of the DGS/VCFS. 相似文献
992.
The prognostic significance of tumor cell detection in intraoperative pleural lavage and lung tissue cultures for patients with lung cancer 总被引:1,自引:0,他引:1
J Buhr KH Bergh?user S Gonner C Kelm EA Burkhardt WM Padberg 《Canadian Metallurgical Quarterly》1997,113(4):683-690
METHODS: Three hundred forty-two patients with lung cancer and 99 patients with nonneoplastic lung diseases (control group) underwent intraoperative pleural lavage with 300 ml physiologic saline solution before (lavage I) and after resection (lavage II). RESULTS: Studies of the lavage fluid in all control patients were negative, that is, there were no false positive findings. Tumor cells were found in lavage I in 132 patients (38.6%) and also in lavage II in 99 of them. In stage I (pT1 N0, pT2 N0) lung cancer, tumor cell detection was possible in 47 patients (28.6%). The 4-year survival of patients with resected non-small-cell lung cancer was 24% (95% confidence interval, 16% to 32%) if lavage I results were positive and 52% (95% confidence interval, 45% to 59%) if lavage I results were negative (all stages, p = 0.007). For patients with stage I disease (n = 164) the 4-year survival was 35% (95% confidence interval, 18% to 52%) if lavage I results were positive (n = 47), and 69% (95% confidence interval, 60% to 78%) if lavage I results were negative (n = 117) (p = 0.037). On multivariate analysis the positive cytologic result in intraoperative pleural lavage was an additional prognostic factor for our patients. To prove how the tumor cells enter the pleural cavity, we performed tissue cultures of tumor-free parenchyma in 23 cases of lung cancer. Tumor cell detection by histology and immunohistology was possible in 16 cases (69.6%). Detection of tumor cells in pleural lavage fluid before resection proves that tumor cells have spread into the pleural cavity. CONCLUSION: The positive result in pleural lavage seems to be a prognostic predictor for patients with lung cancer. 相似文献
993.
EA Mueller MM Moore DC Kerr G Sexton RM Camicioli DB Howieson JF Quinn JA Kaye 《Canadian Metallurgical Quarterly》1998,51(6):1555-1562
Holstein cows (n = 51) that had been diagnosed with toxic puerperal metritis were used to determine the treatment efficacy of various antibiotics. On the day of diagnosis, cows affected with toxic puerperal metritis were assigned randomly to three treatment groups. Cows in groups 1 and 2 received 22,000 IU/kg of procaine penicillin G i.m. for 5 d. In addition, cows in group 2 received an intrauterine infusion of 6 g of oxytetracycline on d 1, 3, and 5. Cows in group 3 received 2.2 mg/kg of ceftiofur sodium i.m. for 5 d. Dependent variables used to determine antibiotic efficacy included milk yield on d 1 through 12, rectal temperature on d 1 through 5, and serum haptoglobin concentration on d 1, 3, and 5. No difference was observed among groups for milk yield on d 1 and 12 or for temperature on d 1 and 5. Serum haptoglobin was elevated to > 10 mg/dl for cows in all groups; however, no difference was observed among groups on d 1 and 5. Because all groups showed a favorable response, this study suggests that there is no difference in treatment efficacy among antibiotics used to treat cows affected with toxic puerperal metritis. 相似文献
994.
Dennis C. Dobyan PhD Garabed Eknoyan Linda S. Magill Myrna Sarrafian Ruth Ellen Bulger 《Microscopy research and technique》1984,1(2):185-198
Modern morphological investigation requires the use of a variety of technological approaches and the employment of rigorous morphometric analysis for an adequate evaluation of the structural and ultrastructural features of a tissue or organ. The introduction of the technique of freeze-cracking of tissue to expose new surfaces has made it possible to quantitate the normal surface characteristics of the glomerular capillaries of the mammalian kidney. This report describes the techniques used for the preparation and quantitative assessment of normal glomerular endothelial morphology. The techniques of in vivo and in vitro vascular perfusion of kidneys as a method of fixation and the freeze-cracking of tissue are outlined in detail. In addition, a morphometric analysis of the endothelial surface characteristics are described and values are reported for the control rat and human kidneys from transplant donors. 相似文献
995.
During the summer of 1987, 10,000 color-coded mailback questionnaires that identified belted and unbelted North Carolina drivers were handed out at the 72 sites that constitute the probability sample for determining the statewide belt use rate in North Carolina. By obtaining identifying information to determine the winner of a $500 prize from among the 5,074 respondents, police-reported traffic accident and conviction records from the North Carolina driver history file were linked to the belted and unbelted respondents. Analyses found that drivers who had been observed not wearing seat belts had 35% more accidents and 69% more convictions than did belted drivers in the previous four-year period. Similar findings were obtained from self-reported belt use. 相似文献
996.
Compared iconic memory processes of 17 undergraduates and 18 retarded Ss (primarily aged 18–28 yrs; IQ 56–77) in 4 experiments. In Exp I, a partial report paradigm was used in which 6 retarded and 6 undergraduate Ss were presented 6 pictures under 4 intervals (0–500 msec). In Exp II, using 5 Ss in each group the same procedure as in Exp I was used but letters as well as pictures were included. Results show that although overall performance for retarded Ss was poor, they did better with letters than with pictures—a reverse of the finding with undergraduate Ss. In Exp III, 2 retarded Ss were given extended practice and incentive to perform well. Asymptote was reached in 10 days but never equaled performance of unpracticed undergraduates. In Exp IV, using 5 Ss in each group, information load was varied from 1 to 4 items, and a masking stimulus was used to interrupt processing following 6 intervals that lasted up to 250 msec. Results show that (1) there are quantitative differences between intelligence groups in iconic capacity; (2) retarded Ss process information more slowly, a difference that increases with increasing information load; and (3) there are substantive structural differences in iconic memory of retarded and nonretarded Ss. (35 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
997.
Smid Henderikus G. O. M.; B?cker Koen B. E.; van Touw Dennis A.; Mulder Gijsbertus; Brunia Cornelis H. M. 《Canadian Metallurgical Quarterly》1996,22(1):3
Two alternative explanations were examined for why selective response activation sometimes starts before stimulus identification is complete (e.g., J. O. Miller & S. A. Hackley, 1992) and sometimes starts only after stimulus identification is complete (e.g., R. De Jong, M. Wierda, G. Mulder, & L. J. M. Mulder, 1988). Distinct psychophysiological methods related to stimulus identification and response selection provided evidence suggesting that partial stimulus information is identified but is or is not used before the stimulus is identified more fully, depending on task requirements. This result (a) suggests strategic adaptation of task performance, (b) is inconsistent with particular discrete and continuous models of information processing, and (c) shows the existence of a central selection mechanism that can prevent the automatic activation of responses associated with preliminary available stimulus information. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
EA Van Leeuwen-Stok AR Jonkhoff AW Visser-Platier LM Dr?ger GJ Teule PC Huijgens GJ Schuurhuis 《Canadian Metallurgical Quarterly》1998,31(5-6):533-544
67Gallium (67Ga) is a radionuclide which accumulates in hematological malignancies and is used for diagnostic imaging. We investigated in this in vitro study the cell cycle dependency of cellular uptake and cytotoxicity of 67Ga. Cell cycle synchronization of cells was achieved by counterflow centrifugal elutriation and the use of cytostatic drugs. The human lymphoma cell lines U-937 and U-715 were used and in elutriation experiments we also used the leukemic cell line HL-60. The transferrin receptor (CD71) expression, 67Ga uptake and cell proliferation inhibition were the parameters measured. We also studied cytotoxicity in various schedules for combination of 67Ga and drugs and the residual proliferative capacity was measured. The CD71 expression in the three cell lines increased from 106-177% on S phase cells and from 118-233% on G2M cells, as compared to the G0/G1 cell fraction. The 67Ga uptake varied from 108-127% for S cells and 128-139% for G2M cells. The drugs chosen induced cell cycle phase accumulation in S and/or G2M phase during preincubation. 67Ga preincubation induced accumulation in the G2M phase. Almost all combinations of 67Ga and drugs resulted in a non-interactive effect, except for methotrexate which resulted in an antagonistic effect. No preferential effect of any of the incubation schemes was seen. CD71 expression and 67Ga uptake were increased in S and G2M cells. Combination of 67Ga with drugs which arrest cells in these cell cycle phases did not result in a change in cytotoxicity. However, these results implicate that 67Ga and the cytostatic drugs tested except for methotrexate might be used together or sequentially in therapy. 相似文献
999.
1000.
A Maran J Lomas H Archibald IA Macdonald EA Gale SA Amiel 《Canadian Metallurgical Quarterly》1993,306(6871):167-171
OBJECTIVES: To compare awareness of hypoglycaemia and physiological responses to hypoglycaemia with human and porcine insulin in diabetic patients who reported loss of hypoglycaemia awareness after transferring to human insulin. DESIGN: Double blind randomised crossover study of clinical experience and physiological responses during slow fall hypoglycaemic clamping with porcine and human insulin. SETTING: Clinical investigation unit of teaching hospital recruiting from diabetes clinics of five teaching hospitals and one district general hospital. SUBJECTS: 17 patients with insulin dependent diabetes mellitus of more than five years' duration who had reported altered hypoglycaemia awareness within three months of transferring to human insulin. MAIN OUTCOME MEASURES: Glycaemic control and frequency of hypoglycaemic episodes during two months' treatment with each insulin. Glucose thresholds for physiological and symptomatic responses during clamping. RESULTS: Glycaemic control did not change with either insulin. 136 hypoglycaemic episodes (eight severe) were reported with human insulin and 149 (nine severe) with porcine insulin (95% confidence interval -4 to 2.5, p = 0.63). 20 episodes of biochemical hypoglycaemia occurred with human insulin versus 18 with porcine insulin (-0.8 to 1, p = 0.78). During controlled hypoglycaemia the mean adrenaline response was 138 nmol/l/240 min for both insulins; neurohormonal responses were triggered at 3.0 (SE 0.2) versus 3.1 (0.2) mmol/l of glucose for adrenaline and 2.5 (0.1) versus 2.5 (0.1) mmol/l for subjective awareness. CONCLUSIONS: These data suggest that human insulin per se does not affect the presentation of hypoglycaemia or the neurohumoral, symptomatic, and cognitive function responses to hypoglycaemia in insulin dependent diabetic patients with a history of hypoglycaemia unawareness. 相似文献