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31.
32.
Most (98%) of the fat in human milk is present as triglycerides. This paper describes the use of a clarification procedure that enables the level of human milk fat to be determined by measurement of glycerol released by enzymic hydrolysis of triglycerides. The method requires only 10-50 microliters milk, thus presenting a possible technique for work with small mammals, and is suitable for use with autoanalysers, permitting rapid sample throughput. 相似文献
33.
Describes the Drug Abuse Reporting Program, the 1st national evaluation study of community-based treatment programs, implemented in the early 1970s. It evolved into a 20-yr longitudinal research program that included during-treatment assessments of client performance, evaluations of treatment effectiveness based on outcomes in the years immediately following treatment, and long-term studies of addiction careers. The Treatment Outcome Prospective Study began in the early 1980s and is now being followed by the Drug Abuse Treatment Outcome Study in the 1990s. These multisite and multimodality studies have helped establish broad-based evidence for treatment efficacy and directions for new studies in the US. The AIDS crisis has had the effect of sharply increasing federal research funds, including grants allocated to enhance and evaluate psychosocial intervention programs for drug users. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
34.
Twenty mothers of preterm babies who had survived to 1 year old, were matched for age and parity of the mother and time of birth of the baby, with 20 mothers delivering fullterm. Bone mineral, body composition and anthropometric measurements were obtained for each mother and analysed using paired t-tests. The only significant difference (P < 0.01) between the groups was a lower fat-free mass in the preterm mothers calculated from skinfold thickness measurements. 相似文献
35.
This paper documents the design, competing systems, results, and conclusions of the CADE-14 ATP System Competition (CASC-14). 相似文献
36.
Allogeneic blood stem cell transplantation is associated with multiple complications. We report a case of pneumoperitoneum without peritonitis associated with colonic pneumatosis in a patient who had undergone an allogeneic peripheral blood cell transplant 相似文献
37.
GP Xue JS Johnson DJ Smyth LM Dierens X Wang GD Simpson KS Gobius JH Aylward 《Canadian Metallurgical Quarterly》1996,45(1-2):120-126
Temperature-regulated expression of recombinant proteins in the tac promoter (Ptac) system was investigated. Expression levels of fungal xylanase and cellulase from N. patriciarum in E. coli strains containing the natural lacI gene under the control of the Ptac markedly increased with increasing cultivation temperature in the absence of a chemical inducer. The specific activities (units per milligram protein of crude enzyme) of the fungal xylanase and cellulase produced from recombinant E. coli strain pop2136 grown at 42 degrees C were about 4.5 times higher than those of the cells grown at 23 degrees C and were even slightly higher when compared with cells grown in the presence of the inducer isopropyl beta-D-thiogalactopyranoside. The xylanase expression level in the temperature-regulated Ptac system was about 35% of total cellular protein. However, this system can not be applied to E. coli strains containing lacIq, which confers over production of the lac repressor, for high-level expression of recombinant proteins. In comparison with the lambda PL system, the Ptac-based xylanase plasmid in E. coli pop2136 gave a considerably higher specific activity of the xylanase than did the best lambda PL-based construct using the same thermal induction procedure. The high-level expression of the xylanase using the temperature-regulated Ptac system was also obtained in 10-litre fermentation studies using a fed-batch process. These results unambiguously demonstrated that the temperature-modulated Ptac system can be used for overproduction of some non-toxic recombinant proteins. 相似文献
38.
MR Gillmore EA Wells EE Simpson DM Morrison MJ Hoppe A Wilsdon 《Canadian Metallurgical Quarterly》1998,24(1):131-151
This paper reports the results of a study in which age (grade level), racial/ethnic, and gender differences in beliefs and perceived norms about drinking were examined in a multi-ethnic urban sample of 4th through 7th grade children. Results showed that older children held beliefs and perceived norms that were more favorable toward drinking than younger children. The major difference between older and younger children lay in their differential estimates of the likelihood of certain consequences occurring and not in their evaluation of these consequences of drinking. Further, older children not only displayed less motivation to comply with their parents and greater motivation to comply with their peers, but they also perceived their parents, as well as their peers, as less disapproving of drinking than did younger children. There were few gender or race/ethnicity differences at these ages in children's beliefs and perceived norms about drinking. 相似文献
39.
SJ Simpson S Shah M Comiskey YP de Jong B Wang E Mizoguchi AK Bhan C Terhorst 《Canadian Metallurgical Quarterly》1998,187(8):1225-1234
40.
Eva Plsgrd Carina Johansson Gang Li Geoff W. Grime J. T. Triffitt 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》1997,130(1-4):431-438
To respond to varying environmental demands the bone tissue in the body is under continual reconstruction throughout life. It is known that metallic elements are important for maintaining normal bone structure, but their roles are not well understood. More information about the effects of metal excess or deficiency is needed to help in the development of metallic bone implants and to improve the treatment of bone fractures and defects. The Oxford Scanning Proton Microprobe (SPM) is being applied in two studies involving metal ions in bone: (1) bone regrowth and bonding to titanium bone implants may be influenced by diffusion of Ti ions into the bone. We are using microPIXE to determine the metal ion content of bone developing in contact with implants of pure Nb, Ti and Ti alloys. (2) Bone lengthening as a surgical procedure is induced by fracturing the bone and allowing it to heal with a small gap between the fractured ends created by the use of external fixators. The gap can be slowly increased during the healing process to stimulate the production of new bone. The enzymes and other constituents of the developing bone need certain metals for their function. Using experimental animals we have studied the concentrations of the metals and whether a deficiency of trace metals limits the optimum rate of bone lengthening. 相似文献