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31.
SF Nielsen SB Christensen G Cruciani A Kharazmi T Liljefors 《Canadian Metallurgical Quarterly》1998,41(24):4819-4832
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
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M Kilstrup SG Jessing SB Wichmand-J?rgensen M Madsen D Nilsson 《Canadian Metallurgical Quarterly》1998,180(15):3900-3906
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This is the second article of a four-part series on gerontology and its applications to the care of elderly patients in nuclear medicine. This article reviews anatomic and physiologic changes and pathology associated with aging. It also discusses tailoring nuclear medicine procedures according to patients' needs and conditions, as well as adopting changes within the nuclear medicine department to better serve older patients. Upon completion of this article, the reader should be able to: (a) describe normal age-related anatomic and physiologic changes that are observed in older patients; (b) identify common age-related disorders; (c) discuss considerations in tailoring nuclear medicine procedures for older patients; and (d) identify changes in the nuclear medicine facility that would better accommodate older patients. 相似文献
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The NADYA Group, integrated in the Spanish Society of Parenteral and Enteral Nutrition (SENPE), and made up of professionals dedicated to Artificial Nutrition, and specifically, to Artificial Nutrition in the home, annually undertakes the task of collecting data on diagnosis, type of support, follow up characteristics, complications, and quality of life, of patients included in programs of at home artificial nutrition in Spain. In the Annual Register corresponding to 1994, 17 hospitality groups have participated, providing 369 patients with Home Enteral Nutrition, and 30 with Home Parenteral Nutrition. Home Enteral Nutrition is mainly applied in patients with neoplasias (36%) or neurological alterations (35%). The most commonly used access route in the nasogastric tube, although there is an observed increase in the application of Percutaneous Gastrostomies (21%) in relation to previous data of the Spanish population. There is an observed complications index of 0.07 episodes/patient-year, a mortality of 30% (neoplasias) and 20% (neurological alterations), and low rehabilitation indexes in this group. In Home Parenteral Nutrition, post-radiation enteritis, neoplasias, and mesenteric ischemia, are the main diagnostic groups. The majority of the patients have a tunneled tube (63%), with 37% using an implanted tube. With an index of hospitalizations of 0.83 hospitalizations/ patient-year, catheter septicemia justifies the majority of the re-hospitalizations derived from nutritional treatment (0.56 hospitalizations/patient-year), note the mortality of 37%. There are complete rehabilitations, continuing the previously normal activity in 80% of the cases. 相似文献
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TA Gudasheva SS Boyko VKh Akparov RU Ostrovskaya SP Skoldinov GG Rozantsev TA Voronina VP Zherdev SB Seredenin 《Canadian Metallurgical Quarterly》1996,391(1-2):149-152
Using high-performance liquid chromatography, gas-chromatography and chromato-mass spectrometry methods a novel endogenous cyclic dipeptide cyclo-prolylglycine was identified in rat brain. Its content according to gas chromatography is 2.8 +/- 0.3 nmol/g wet brain. Synthetic cyclo-prolylglycine has demonstrated antiamnesic activity in the passive avoidance test in rats at a dose of 0.1 mg/kg i.p. Cyclic dipeptide cyclo-prolylglycine seems to be a memory facilitating substance and its presence in rat brain suggests the existence of a new mechanism of memory regulation. 相似文献
39.
SB D'Avanzo T Graziano DE Metz N Schiavetti RL Whitehead 《Canadian Metallurgical Quarterly》1998,31(4):337-45; quiz 345-6
Simultaneous communications combines both spoken and manual modes to produce each word of an utterance. This study investigated the potential influence of alterations in the temporal structure of speech produced by inexperienced signers during simultaneous communication on the perception of final consonant voicing. Inexperienced signers recorded words that differed only in the voicing characteristic of the final consonant under two conditions: (1) speech alone and (2) simultaneous communication. The words were subsequently digitally edited to remove the final consonant and played to 20 listeners who, in a forced-choice paradigm, circled the word they thought they heard. Results indicated that accurate perception of final consonant voicing was not impaired by changes in the temporal structure of speech that accompanied the inexperienced signers' simultaneous communication. 相似文献
40.
GH Westrich ML Allen SJ Tarantino B Ghelman R Schneider RS Laskin SB Haas TP Sculco 《Canadian Metallurgical Quarterly》1998,(356):125-133
The efficacy of ultrasound compared with ascending venography for the detection of deep venous thrombosis immediately after total knee arthroplasty was assessed after a 2-year interval. One hundred thirty-seven patients were eligible for the study; however, 31 patients received only one of the screening methods and a color Doppler examination was inconclusive in six patients. Therefore, 100 patients had a Doppler examination and a venogram. Overall, the sensitivity of ultrasound was 85%, the specificity 97%, the positive predictive value 85%, the negative predictive value 97%, and the accuracy 95%. The sensitivity in the calf was 83%, in the popliteal vein 86%, and in the femoral vein 100%. Two years ago, the initial assessment of ultrasound for the detection of deep venous thrombosis after surgery in patients who had total joint arthroplasty revealed a 75% sensitivity, 99% specificity, 91% positive predictive value, 97% negative predictive value, and 97% accuracy. The sensitivity in the calf was 83%; the sensitivity in the popliteal vein was 40%; and the sensitivity in the femoral vein was 50%. After 2 years of using this screening test with one technician and one radiologist, an improvement with this noninvasive technique was shown. However, it was found that Doppler imaging is not as sensitive as venography for detecting calf thrombi. Any imaging technique should be validated by each institution to determine the validity of the instrument and the learning curve of the technician administering the examination. 相似文献