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61.
A number of biological and physical stimuli have been evaluated as inducers of pseudopterosin biosynthesis in the sea whip Pseudopterogorgia elisabethae. Data indicate that the production of pseudopterosins can be significantly increased in response to high levels of predation by the mollusk Cyphoma gibbosum and in response to decreased levels of UV/visible radiation. High levels of feeding by Chaetodon capistratus and an artificial wounding of the sea whip did not result in increased pseudopterosin levels.  相似文献   
62.
The temperature dependence of the yield stress and energy absorbing capacity of zinc foam, having a density between 0.05 and 0.07 of that of zinc, was determined over a range of temperatures from 0.1 Tm to 0.7 Tm approximately. With increase in temperature over this temperature range, the yield stress and energy absorbing capacity of the foam at first increased, and then subsequently decreased, above room temperature. At low temperatures,e.g. 0.1 Tm, the foam disintegrated into powder, and the energy absorbing efficiency parameters were high and independent of the foam density. In contrast, at the highest temperatures,e.g. 0.7 Tm, the energy absorbing efficiency parameters were lower and decreased with increase in density. The results are interpreted on the basis of the change in deformation mode which occurs in the zinc matrix of the foam over this temperature range,i.e. the transition from cleavage at the low temperature to plastic flow at the high temperature of deformation.  相似文献   
63.
"Left to themselves under constant situational pressures, groups modify their behavior at a characteristic rate which is independent of the demands placed on them. However, depending on the nature of the task, a given rate of behavior modification may have different consequences for the rate of improvement in some performance criterion such as errors." (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
64.
65.
In recent years, home visitation services have been widely promoted as a means of preventing health and developmental problems in children from vulnerable families. The U.S. Advisory Board of Child Abuse and Neglect, for example, recommended that home visitation services be made available to all parents of newborns to prevent child abuse and neglect.  相似文献   
66.
A large number of substituted chalcones have been synthesized and tested for antileishmanial and lymphocyte-suppressing activities. A subset of the chalcones was designed by using statistical methods. 3D-QSAR analyses using 67 (antileishmanial activity) and 63 (lymphocyte-suppressing activity) of the compounds for the training sets and 9 compounds as an external validation set were performed by using the GRID/GOLPE methodology. The Smart Region Definition procedure with subsequent region selection as implemented in GOLPE reduced the number of variables to approximately 1300 yielding 3D-QSAR models of high quality (lymphocyte-suppressing model, R2 = 0. 90, Q2 = 0.80; antileishmanial model, R2 = 0.73, Q2 = 0.63). The coefficient plots indicate that steric interactions between the chalcones and the target are of major importance for the potencies of the compounds. A comparison of the coefficient plots for the antileishmanial effect and the lymphocyte-suppressing activity discloses significant differences which should make it possible to design chalcones having a high antileishmanial activity without suppressing the proliferation of lymphocytes.  相似文献   
67.
Antimicrobial therapy can be a confounding factor in the diagnosis of urinary tract infection and is not always reported to laboratories by physicians. We developed a microbiologic assay for screening urine specimens for antimicrobial agents. Bacillus stearothermophilus was used as the indicator bacteria. A total of 1,921 urine specimens from three hospitals in Taiwan were screened using this assay. Of the samples assayed, 1,293 were positive for antimicrobial agents. Agreement between information provided by physicians and laboratory findings was 68.5% (419/612). In the presence of antimicrobial agents in the urine samples, the isolation of yeasts and Pseudomonas aeruginosa increased dramatically, from 4.5 to 19.5% and 4.2 to 13.2%, respectively. Additionally, Escherichia coli was more resistant to gentamicin (75.3% vs 48.7%, p < 0.0001), norfloxacin (85.2% vs 64.6%, p = 0.0006) and co-trimoxazole (58.5% vs 35.5%, p = 0.0018). In view of the high rate of occurrence of antimicrobial agents in urine specimens and the lack of information provided by most physicians to laboratories, a screening method to detect the presence (or absence) of antimicrobials in urine specimens may be a useful tool particularly in areas such as Taiwan where antimicrobial agents are commonly abused.  相似文献   
68.
Healing in the GI tract is rapid when free of complications: Unlike cutaneous healing, in which progress can be observed on a daily basis and intervention instituted early if necessary, healing of the intestinal anastomosis is anatomically obscured from inspection, allowing the surgeon only the patient's parameters of general well-being to judge the success of the operation. For the same reason, complications usually require re-operation, with the associated morbidity of a laparotomy and additional general anesthetic. This places a great responsibility on the surgeon to be cognizant of all the preoperative, intraoperative, and postoperative factors relating to anastomotic healing that might compromise the healing process. Bearing these in mind, along with attention to technical detail, should limit complications to an acceptable level. Patients most at risk are (1) those who perioperatively develop physiologic problems that lead to shock, hypoxia, and resultant anastomotic ischemia, (2) those with radiation-induced tissue injury, (3) those with sepsis, and (4) those with preoperative bowel obstruction. Malnourishment, malignancy, diabetes, steroids, and age also influence outcome to varying degrees. Future advancement in the field of GI healing lies in our ability to manipulate the early struggle between collagen synthesis and collagen breakdown. A profound understanding of the molecular and biochemical pathways and the factors that control them will bring us closer to this goal. Clinically, this may be accomplished by the introduction of wound healing enhancers into the anastomotic site, possibly by incorporating them into suture materials, biofragmentable anastomotic rings, or staple materials. Already much is known about the influence of different cytokines and growth factors on collagen regulation, knowledge that will help resolve many of the long-standing problems associated with GI surgery.  相似文献   
69.
The effects of faking on criterion-related validity and the quality of selection decisions are examined in the present study by combining the control of an experiment with the realism of an applicant setting. Participants completed an achievement motivation measure in either a control group or an incentive group and then completed a performance task. With respect to validity, greater prediction error was found in the incentive condition among those with scores at the high end of the predictor distribution. When selection ratios were small, those in the incentive condition were more likely to be selected and had lower mean performance than those in the control group. Implications for using personality assessments from select-in and select-out strategies are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
70.
Summary The chemical and physical characteristics, as well as the percentages of the fatty acids in Patauá palm oil, have been determined. The sample of authentic oil studied contained 79.94 per cent of unsaturated acids in which oleic acid predominated, there being only 3.4 per cent of linoleic acid. The saturated acids, which amounted to 14.45 per cent, consisted of a mixture of palmitic and stearic acids along with a very small quantity of triacontanic acid, the source of which was probably the fruit wax dissolved in the oil. Attention is called again to the similarity of this fine edible oil and olive oil, in appearance, characteristics, and composition, insofar as the proportions of the major fatty acids are concerned.  相似文献   
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