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151.
Evaluation of serum SOD and MDA level was done in 21 first episode renal stone formers, 9 recurrent stone formers, 20 patients with obstructive uropathy other than urolithiasis and 12 patients with urinary infection. Twenty-two healthy volunteers were taken as controls. The level of SOD in respective groups was 2.12±0.84, 2.78±0.85, 1.42±0.31, 1.98±0.70 and 2.32±0.62 units/ml and of MDA was 2.61±1.07, 2.69±1.15, 1.65±0.33, 1.33±0.34 and 1.55±0.48 n mol/ml respectively. The results indicate increased peroxidative stressin nephrolithiasis only. Since SOD level was normal in all groups, this increased peroxidative stress in nephrolithiasis should be due to factors other than this one.  相似文献   
152.
Sialic acid, the end moieties of the carbohydrate chains are biologically important and essential for functions of glycoconjugates and are reported to be altered in cancer patients. Two hundred and twenty five breast cancer (BC) patients, 100 patients with benign breast disease (BBD) and 100 healthy females (controls) were enrolled for the study. Eight hundred and twenty four follow-up samples of 225 breast carcinoma patients were also evaluated. The association of sialic acid forms, sialyltransferase and α-2–6 sialoproteins levels with presence and extent as well as prognosis of breast carcinoma was studied. Serum sialic acid forms and sialyltransferase revealed significantly elevated levels among untreated breast cancer patients as compared to the controls, patients with BBD as well as cancer patients in remission. Non-responders showed comparable levels of the markers with those found in breast cancer patients at the time of diagnosis. Higher levels of sialic acid forms at diagnosis were associated with poor prognosis. A positive correlation between serum levels of different forms of sialic acids and extent of malignant disease was observed. The changes in serum proteins with terminal α-2–6 sialic acid correlated well with alterations in the levels of sialic acid forms and sialyltransferase. Malignant tissues showed elevated levels of sialic acid and sialyltransferase as compared to surrounding normal tissues. The results suggested potential utility of these markers in evaluation of clinical outcome.  相似文献   
153.
P. Papon 《Research Policy》1975,4(3):214-244
As in many western industrialized countries, the French State began to support technological research heavily after 1945. Public funds were mainly invested in high technologies (Nuclear, Aerospace, Computers) but as soon as awareness of technological backwardness of French industry made progress in the sixties, the French government decided to extend its financial support to other industrial sectors. A survey of the policies which have been worked out reveals that the French State has played the role of a bright entrepreneur without a technological and idustrial strategy, which explains why some of these policies are now at a dead end.  相似文献   
154.
P. D’Este  P. Patel 《Research Policy》2007,36(9):1295-1313
This paper examines the different channels through which academic researchers interact with industry and the factors that influence the researchers’ engagement in a variety of interactions. This study is based on a large scale survey of UK academic researchers. The results show that university researchers interact with industry using a wide variety of channels, and engage more frequently in the majority of the channels examined - such as consultancy & contract research, joint research, or training - as compared to patenting or spin-out activities. In explaining the variety and frequency of interactions, we find that individual characteristics of researchers have a stronger impact than the characteristics of their departments or universities. Finally, we argue that by paying greater attention to the broad range of knowledge transfer mechanisms (in addition to patenting and spin-outs), policy initiatives could contribute to building the researchers’ skills necessary to integrate the worlds of scientific research and application.  相似文献   
155.
Prostate Specific Antigen (PSA) has emerged as the most applicable and important tumor marker for carcinoma prostate. In the present study PSA was determined in serum of healthy subjects, patients of benign prostate hypertrophy (BPH) and Carcinoma Prostate (Ca−P) to evaluate its diagnostic efficiency in day to day management of prostate cancer patients and in differentiating patients of early prostate cancer from those with BPH. Receiver operating characteristic curve (ROC) revealed 2 ng/ml and 10 ng/ml cut off serum PSA level for BPH and untreated carcinoma prostate patients (Ca−P). An extremely significant increase (P<0.0001) was observed in mean PSA concentration in BPH patients and adenocarcinoma prostate patients when compared to healthy males. Clinical relevance of PSA was highlighted by a case study of cancer patient prior to any therapy till death.  相似文献   
156.
Although potassium is critical for normal electro physiology, the associations between pre-operative serum potassium level and peri-operative adverse events such as arrhythmias in cardiac surgery have not been examined in detail. The objective of this study was to determine the prevalence of abnormal pre-operative serum potassium levels and whether such levels were associated with adverse peri-operative events in 50 patients undergoing coronary artery bypass grafting. Intra-operative and post-operative arrhythmias, the need for cardio-pulmonary resuscitation, cardiac death and death due to any cause prior to discharge from the post-operative intensive care unit were studied. The incidence for adverse outcome was 0.5% for death, 0.5% for cardiac death and 2% for cardio pulmonary resuscitation in patients with hypokalemia (serum potassium level <3.5 meq. L−1). Hypokalemia was found to be a predictor of serious peri-operative (OR:2.2; 95% Cl: 1.2–4.1) and post-operative arrhythmias (OR: 1.7;95%Cl: 1.0–2.7). Pre-operative potassium repletion is low cost and low risk treatment measure and the data from this study suggests that screening and repletion be considered in patients scheduled for cardiac surgery.  相似文献   
157.
We present a practical way of adapting and using four research-based assessments for different purposes in an electricity and magnetism course for K-8 science teachers. The course is designed to accomplish conceptual change toward accepted scientific conceptions as well as introducing teachers to materials and activities appropriate for their classrooms. Our data support that using the research-based tests to identify alternative conceptions and discuss test results with teachers is a promising way to use the knowledge of alternative conceptions in professional development. We also identify some mismatches between the research of conceptual change and its use in programs of professional development.
Ji ShenEmail:
  相似文献   
158.
Students rarely ask questions related to course content in large-format introductory classes. The use of a Web-based forum devoted to student-generated questions was explored in a second-semester introductory biology course. Approximately 80% of the enrolled students asked at least one question about course content during each of three semesters during which this approach was implemented. About 95% of the students who posted questions reported reading the instructor's response to their questions. Although doing so did not contribute to their grade in the course, approximately 75% of the students reported reading questions posted by other students in the class. Approximately 60% of the students reported that the Web-based question-asking activity contributed to their learning of biology.  相似文献   
159.
OBJECTIVE: The Children's Advocacy Center (CAC) model of child abuse investigation is designed to be more child and family-friendly than traditional methods, but there have been no rigorous studies of their effect on children's and caregivers' experience. Data collected as part of the Multi-Site Evaluation of Children's Advocacy Centers were used to examine whether CACs improve caregivers' and children's satisfaction with investigations. METHODS: Nonoffending caregiver and child satisfaction were assessed during research interviews, including the administration of a 14-item Investigation Satisfaction Scale (ISS) for caregivers. Two hundred and twenty-nine sexual abuse cases investigated through a CAC were compared to 55 cases investigated in communities with no CAC. RESULTS: Hierarchical linear regression results indicated that caregivers in CAC cases were more satisfied with the investigation than those from comparison sites, even after controlling for a number of relevant variables. There were few differences between CAC and comparison samples on children's satisfaction. Children described moderate to high satisfaction with the investigation, while a minority expressed concerns about their experience. CONCLUSIONS: The CAC model shows promise for improving families' experiences, but to build upon this promise, agencies will need to systematize procedures for refining and adapting the model as new research becomes available.  相似文献   
160.
Quality assurance in engineering education is a multifaceted problem further augmented by the stakeholders of engineering education. Students, parents and employers are rightfully questioning the quality of the curriculum, the instructional delivery, the learning environment, accessibility to learning technologies and equipment, employability as well as the possibilities of lifelong learning and the improvement of knowledge (Karapetrovic 2002 Karapetrovic, S. 2002. Why and how to develop a meaningful quality assurance system in engineering schools. Int. J. Engg. Educ, 18(3): 285294. [Web of Science ®] [Google Scholar]). The purpose of the study is, therefore, to identify the parameters that influence the quality of an engineering education system and develop an integrated model of hierarchical structuring and a concept map for pre-identified concept elements through a process of iterative-interactive consensus-driven methodology, as advocated by second-generation system design paradigm for evolving knowledge scenario of concepts related to quality engineering education.  相似文献   
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