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981.
Sera samples of 7 microscopic haematuria cases collected before and after treatment with Diethylcarbamazine citrate, (DEC), 9 microfilaraemic cases and 19 endemic normal individuals were analysed for filarial antigen and IgG antibody levels. Filarial antigen was detected in 5 of the 7 microscopic haematuria cases, of which 3 turned negative for antigen after treatment with DEC. While none of the 7 haematuria cases were positive for filarial IgG antibodies, before the DEC treatment, all of them turned positive after DEC treatment. The sensitivity and specificity values(to detect mf +ve cases) were 89% and 90% respectively for the detection of filarial antigen and 78% and 95% respectively for the detection of filarial IgG antibodies.  相似文献   
982.
With the growing interest in the concept of free radicals in the pathogenesis of myocardial ischemia, it was thought worthwhile to study the changes in lipid peroxides and antioxidant enzyme glutathione peroxidase (GPx) in ischemic heart disease (IHD). The study was carried out on 76 patients of IHD-38 of acute myocardial infarction (AMI) and 38 of stable ischemic heart disease (SIDH). They were age and sex matched with 38 normal healthy controls. A significant increase (p<0.001) in lipid peroxides as malondialdehyde (MDA) (5.9±0.7 mmol/L) and a decrease in GPx (24.6±2.2 U/gmHb) was found in patients of AMI when compared with controls. There was no significant difference in these values in SIHD. Thus this study confirms the earlier findings that MDA and GPx are useful parameters in IHD and their magnitude is dependent on severity and/or duration of ischemia. We suggest that these tests would be of use in smaller institutions with limited facilities.  相似文献   
983.
Cataglyphis     
Cataglyphis is an ant of desert regions and has a behavioural pattern comparable with that of the bee, but much easier to study. It has a well-developed system of foraging and navigating and a social organisation well adapted to its environment. This review, by two independent research workers who have devoted much time to field studies, is the first to bring together most of the existing information about these fascinating insects.  相似文献   
984.
Two small-gain theorems and a passivity theorem yielding stability results for general feedback systems are shown to be equivalent.  相似文献   
985.
死亡的脸     
人们都说人应该有尊严的生,有尊严的死.然而在耶鲁大学外科与医学史教授舍温·努兰医生的眼中,很少有人能够有尊严的死去.  相似文献   
986.
Case histories were compiled of 100 instances of technological change in 102 manufacturing companies in eight industries in Ireland, Spain and Mexico. The cases are analyzed for the source of initial ideas and for sources of technology employed in resolving major problems.Technology is found to flow principally through informal channels within industries. Very little information was obtained from the formal mechanisms or institutions normally considered central to the technology transfer process.Foreign subsidiaries obtain the greatest proportion of their technology from their parent firms. Surprisingly, they are found to have several channels of technology blocked to them, which are more readily available to domestic firms. Domestic firms, in many ways have easier access to foreign technology than do the subsidiaries of multinational firms.Product and process innovations originate in somewhat different quarters. Process innovations are slightly more likely to be based on foreign technology; product innovations are more likely to be based on domestic technology.The results reported in the present paper are very similar in many ways to results reported previously in Brazil and Australia.  相似文献   
987.
988.
The purpose of the current article is to examine the impact of laboratory demonstrations and computer visualizations on learning in a third-year fluid mechanics course at Norwegian University of Science and Technology (NTNU). As a first step, on entering the course, students were exposed to a laboratory demonstration focusing on the nature of waves. Students were subsequently taught the theory of wave mechanics in a regular class along with exercises. Finally, the computer algebra system Maple was used to simulate physical properties of the waves using the mathematical equations. The illustrations throughout the paper are examples of some of the pedagogical devices that students were exposed to during the project. The students enjoyed the demonstrations, but there are some indications that the interventions did not help to improve learning of phenomena.  相似文献   
989.
We designed an interrupted case study to teach aerobic cellular respiration to major and nonmajor biology students. The case is based loosely on a real-life incident of rotenone poisoning. It places students in the role of a coroner who must determine the cause of death of the victim. The case is presented to the students in four parts. Each part is followed by discussion questions that the students answer in small groups prior to a classwide discussion. Successive parts of the case provide additional clues to the mystery and help the students focus on the physiological processes involved in aerobic respiration. Students learn the information required to solve the mystery by reading the course textbook prior to class, listening to short lectures interspersed throughout the case, and discussing the case in small groups. The case ends with small group discussions in which the students are given the names and specific molecular targets of other poisons of aerobic respiration and asked to determine which process (i.e., glycolysis, citric acid cycle, or the electron transport chain) the toxin disrupts.  相似文献   
990.
ABSTRACT: An evaluation of interactive video conferencing and Web-assisted instruction to deliver a multidisciplinary course entitled Phytochemicals in Fruits and Vegetables to Improve Human Health was conducted during the spring semesters of 1999 and 2001. This course was taught by 20 instructors from 11 institutions to 49 students during spring 2001, which was an increase of 53% over spring 1999. Weekly 3-h lectures were delivered by the Trans-Texas Videoconference Network integrated with PowerPoint® or HTML slides available on the course Web site ( http://phytochemicals.tamu.edu ). Qualitative and quantitative data were collected through formative and summative methods. Participants expressed their satisfaction with course format and the need for technical support for interactive videoconferencing.  相似文献   
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