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991.
L Baer JZ Parra-Carrilo I Radichevich GS Williams 《Canadian Metallurgical Quarterly》1977,86(3):257-260
Experiments with synthetic substance P incubated in whole blood show that apart from a moderate loss of activity immediately on exposure of the peptide to whole blood, it is inactivated slowly in this tissue, approximately 25% of control activity remaining after 30 min incubation. Incubation with plasma did not result in the degradation of substance P. The attenuation of substance P activity in blood may be due to enzymatic destruction within erythrocytes. 相似文献
992.
Thirty-four patients with liver disease were studied with a research model of the Varian Six Second body scanner. Useful information was gained in patients with a variety of hepatic disorders. This scanner permits resolution of normal hepatic parenchymal detail which has not been reported previously and has reduced the streak artifacts originating from high- and low-CT objects which have been a major source of image degradation with other units. 相似文献
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994.
Endothelial mitotic activity of the rabbit jugular veins depending on the daytime of trauma infliction was studied. In the first series of experiments (I), the operations were performed from 8 to 10 a. m., and in the second (II)-- from 8 to 10 P. M. After the operation one animal was killed every 3 hour, for 5 days. Mitotic activity (MK %) was studied continuously 8 mm from the wound edge in flat film preparations. The data obtained were statistically treated using approximation of the process course by the method of weighed sliding averages. Independently of the time of trauma infliction, the first mitoses in the endothelium appear after 21 h. Further, mitotic proliferation has a wavy character of different intensity in different tissue areas. Lack of similarity in the organism circadiam phase at the time of operation, produces distinct differences in the course of the process which are seen in asynchronity of the daytimes when the rise and recession of mitotic activity occur and in different length of these waves. In I series the length of these waves equals to 36, and in II series-- to 48 h. After the evening operation, 24-hour rhythm superimposed on its aliquat 48-hour activity is slearly seen. After the morning operation, daily rhythm is not observed. After the evening operation the process is more intense and has a greater length along the endothelial layer. 相似文献
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996.
997.
OBJECTIVE: To assess the relation between male and female medical leadership. DESIGN: Cross sectional study on predictive factors for female medical leadership with data on sex, age, specialty, and occupational status of Norwegian physicians. SETTING: Oslo, Norway. SUBJECTS: 13 844 non-retired Norwegian physicians. MAIN OUTCOME MEASURE: Medical leaders, defined as physicians holding a leading position in hospital medicine, public health, academic medicine, or private health care. RESULTS: 14.6% (95% confidence interval 14.0% to 15.4%) of the men were leaders compared with 5.1% (4.4% to 5.9%) of the women. Adjusted for age men had a higher estimated probability of leadership in all categories of age and job, the highest being in academic medicine with 0.57 (0.42 to 0.72) for men aged over 54 years compared with 0.39 (0.21 to 0.63) for women in the same category. Among female hospital physicians there was a positive relation between the proportion of women in their specialty and the probability of leadership. CONCLUSION: Women do not reach senior positions as easily as men. Medical specialties with high proportions of women have more female leaders. 相似文献
998.
M Valbuena K Bandeen-Roche GS Rubin B Munoz SK West 《Canadian Metallurgical Quarterly》1999,40(2):280-288
PURPOSE: To report on the usefulness of the Activities of Daily Vision Scale (ADVS) questionnaire for assessing visual functioning, a population-based sample of elderly Americans. METHODS: The ADVS questionnaire was administered to a population-based sample of 2520 community-dwelling individuals 65 to 84 years of age in Salisbury, MD. Items and subscales were evaluated for internal consistency, item discrimination, and content validity. Published subscale groupings and item associations in our population were compared for coherence using correlation, factor, and cluster analyses. Whole-sample and race- and gender-specific analyses were conducted. External validity was explored by regressing ADVS scores on standard psychophysical vision measures. RESULTS: ADVS scores were skewed to high visual functioning levels; approximately 60% of the population had function scores of 95 or better (of a possible 100). The overall, night driving, and near vision scales were internally consistent and had strong item-subscale associations; the day driving and glare subscales were not acceptable regarding these properties. The far vision subscale was acceptably scalable but only weakly differentiated from the other subscales. Overall, night driving, near vision, and far vision scores were all statistically and independently associated with multiple psychophysical vision measures. Findings were consistent across race and gender subgroups. CONCLUSIONS: As assessed by the ADVS, reported visual functioning is high in our representative older population. The overall scale and selected subscales effectively distinguish persons along a spectrum of ability. They correlate with measures of visual impairment in a reasonable way and thus hold promise for risk factor investigations. The published day driving and glare subscales should be examined for relevance and consistency before being applied in population-based settings. Methods specific to population-based settings should be investigated for their ability to better elicit additional visual function dimensions and early visual disability. 相似文献
999.
Cells capable of bone production engraft from whole bone marrow transplants in nonablated mice 总被引:1,自引:0,他引:1
SK Nilsson MS Dooner HU Weier B Frenkel JB Lian GS Stein PJ Quesenberry 《Canadian Metallurgical Quarterly》1999,189(4):729-734
Allogeneic and autologous marrow transplants are routinely used to correct a wide variety of diseases. In addition, autologous marrow transplants potentially provide opportune means of delivering genes in transfected, engrafting stem cells. However, relatively little is known about the mechanisms of engraftment in transplant recipients, especially in the nonablated setting and with regard to cells not of hemopoietic origin. In particular, this includes stromal cells and progenitors of the osteoblastic lineage. We have demonstrated for the first time that a whole bone marrow transplant contains cells that engraft and become competent osteoblasts capable of producing bone matrix. This was done at the individual cell level in situ, with significant numbers of donor cells being detected by fluorescence in situ hybridization in whole femoral sections. Engrafted cells were functionally active as osteoblasts producing bone before being encapsulated within the bone lacunae and terminally differentiating into osteocytes. Transplanted cells were also detected as flattened bone lining cells on the periosteal bone surface. 相似文献
1000.
RL Larsen PM Applegate DA Dyar PA Ribeiro SD Fritzsche NF Mulla GS Shirali MA Kuhn RE Chinnock PM Shah 《Canadian Metallurgical Quarterly》1998,32(2):515-520
OBJECTIVES: The purpose of this study was to determine the feasibility, safety and diagnostic accuracy of dobutamine stress echocardiography (DSE) for evaluating posttransplant coronary artery disease (TxCAD) in children, and to determine the frequency of selected cardiac events after normal or abnormal DSE. BACKGROUND: Posttransplant coronary artery disease is the most common cause of graft loss (late death or retransplantation) after cardiac transplantation (CTx) in children. Coronary angiography, routinely performed to screen for TxCAD, is an invasive procedure with limited sensitivity. The efficacy of DSE for detecting atherosclerotic coronary artery disease is established, but is unknown in children after CTx. METHODS: Of the 78 children (median age 5.7 years, range 3 to 18) entered into the study, 72 (92%) underwent diagnostic DSE by means of a standard protocol, 4.6 +/- 1.9 years after CTx. The results of coronary angiography performed in 70 patients were compared with DSE findings. After DSE, subjects were monitored for TxCAD-related cardiac events, including death, retransplantation and new angiographic diagnosis of TxCAD. RESULTS: No major complications occurred. Minor complications, most often hypertension, occurred in 11% of the 72 subjects. The sensitivity and specificity of DSE were 72% and 80%, respectively, when compared with coronary angiography. At follow-up (21 +/- 8 months), TxCAD-related cardiac events occurred in 2 of 50 children (4%) with negative DSE, versus 6 of 22 children (27%) with positive DSE (p < 0.01). CONCLUSIONS: DSE is a feasible, safe and accurate screening method for TxCAD in children. Positive DSE identifies patients at increased risk of TxCAD-related cardiac events. Negative DSE predicts short-term freedom from such events. 相似文献