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101.
PJ Heins KA Karpinia JW Maruniak JE Moorhead CH Gibbs 《Canadian Metallurgical Quarterly》1998,69(7):812-818
Probing pain threshold (PPT) assessments were conducted in the facial and oral sulci of maxillary central incisors and first molars of 10 periodontally healthy adults. All subjects were systemically healthy, free of pain, and reported no current medication usage. A computer-linked electronic probe, modified to deliver steadily increasing forces up to 200 grams, was used to collect the data. The system contained a subject operated "off-switch" which, upon activation, signaled the computer to record the subject's PPT. Assessments of each subject's PPTs were conducted on 3 separate occasions at 7-day intervals. Results indicated that the facial sulci of the incisors were the most pain sensitive. They displayed a mean PPT of 50.9 +/- 26.6 grams. The oral sulci of the incisors exhibited a mean PPT of 76.5 +/- 45.2 grams. Facial and oral sulci of the molars evidenced mean PPT values of 102.6 +/- 52.1 grams and 113.5 +/- 51.3 grams, respectively. These data suggest that sulci associated with incisor teeth are nearly twice as pain sensitive as sulci associated with molar teeth. In addition, facial sulci are significantly more pain sensitive than oral sulci. Data did not indicate a visit effect nor a side-of-mouth effect on PPT values. 相似文献
102.
This paper describes a successful project using computer animation to teach the concepts of microprogramming to lower division computer science majors. The students write a simulator for the Mic-1 horizontal microcontroller described in the book Structured Computer Organization by Tanenbaum. The simulation is enhanced by the use of a graphical representation of the machine to animate the simulation. This creative use of computer animation enables the students to see the results of their simulation without having to write an extensive user interface. They can concentrate on implementing the instruction cycle, an activity that directly enhances their understanding of microprogramming and the conventional machine level. The XTango animation package is used, making the animation facility portable to any Unix system with an X display. The user interface and additional instructional material are available via the web 相似文献
103.
BK Kishore L Fuming P Maldague PM Tulkens PJ Courtoy 《Canadian Metallurgical Quarterly》1996,74(6):1025-1037
In the companion paper, we report that a single injection of poly-D-glutamic acid causes an acute lysosomal storage condition and apparently impairs the lysosomal fission dynamics. The present paper addresses the mechanisms of these two alterations using a combination of in vivo and in vitro biochemical approaches. After a single intravenous injection, 14C-poly-D-glutamic acid was rapidly cleared from the plasma and appeared in the urine. Yet, a small but sizable fraction of the injected polymer was taken up by the kidney cortex through a saturable process (Kuptake, 150 mg/kg body wt; uptakemax 96 micrograms/g cortex). Analytical subcellular fractionation of cortex homogenates demonstrated that at initial stages, the 14C label was predominantly associated with subcellular particles of intermediate size and low equilibrium density, and was therefore slowly transferred to larger particles equilibrating at high density, then codistributing with the lysosomal hydrolases. At a concentration of 10 mg/ml (equivalent to its estimated concentration in lysosomes), poly-D-glutamic acid formed micronic aggregates ( > or = 10 microns) when brought to solution at pH < or = 6 in relation to its decreased ionization (pKa of lateral chains approximately equal to 4.25). Finally, 1 day after the injection of poly-D-glutamic acid, the activities of several lysosomal enzymes (hexosaminidase, cathepsin B, acid sphingomyelinase, and sulfatase B), but not of all of them (eg, acid phosphatase), were increased in the kidney cortex. We propose that poly-D-glutamic acid reaches lysosomes by adsorptive endocytosis and becomes concentrated within these organelles because its withstands hydrolysis until it forms aggregates or precipitates, causing a decrease in the fluidity or the deformability ("gelling") of the lysosomal matrix. This should alter the dynamics of intercommunication of these organelles by impairing their fission without a proportionate effect on their fusion properties. In addition, the data suggest that the presence of poly-D-glutamic acid directly or indirectly slows down the degradation of several lysosomal enzymes. 相似文献
104.
Non-insulin-dependent (or type 2) diabetes mellitus is a common, underdiagnosed and growing disease in our society. It is responsible for increased morbidity and mortality and represents an important public health problem. This polygenic disease is often expressed late in life and its evolution is accelerated by environmental factors leading to obesity. It combines defects in both insulin secretion and insulin action, and such defects are present in various proportions according to the type of patient and the stage of the disease. Diet and physical activity recommendations are the basis of the treatment. Current pharmacological approaches aim at improving insulin secretion and/or insulin cellular action. After secondary failure to oral drugs, insulin therapy should be initiated, the patient becoming "insulin-requiring". A synergy should be searched in the combination of various therapeutic modalities in order to improve the glycaemic control. 相似文献
105.
KK M?kinen CY Chen PL M?kinen CA Bennett PJ Isokangas KP Isotupa HR Pape 《Canadian Metallurgical Quarterly》1996,30(3):180-188
The concern with nursing research in the future work of nurse graduates. Expectations from the viewpoint of the nurse researcher. Keeping in mind the concerns which occupy nurse researchers now and in the future, expectations are raised of the graduates of degree programmes in nursing science which are now also being established in the Federal Republic of Germany. This takes into account the structurally determined areas of self determined action in new fields of professional practice. Nurse graduates will be seen as "change agents" in their future areas of work and will have three essential aspects of involvement with nursing research: 1. they themselves will conduct research 2. they will receive, put into practice and transmit results of nursing research 3. they will initiate and commission nursing research projects. According to the broad topics of nursing research, requirements for nurses to act as professionals in their new working fields are formulated referring to the given structural conditions in Germany. 相似文献
106.
107.
BACKGROUND: A durable power of attorney for health care (DPA) allows a person to appoint a surrogate decision-maker for any future period of mental incapacity. The absence of advance directives can lead to confusion and the expenditure of resources while trying to exert a substituted judgment. METHODS: The Wisconsin DPA was presented with an organized pilot program to 150 residents who had been judged by their social workers to have the capacity to make informed decisions regarding medical care. The reasons residents gave for accepting or rejecting a DPA were analyzed. RESULTS: Seventy-nine percent prepared a DPA. Reasons for signing included allowing the resident to decide who would make medical decisions and assuring that specific wishes would be carried out. Twenty-one percent did not execute a DPA. Reasons were categorized as confusion and misunderstanding regarding the legal system, mistrust, or social isolation. CONCLUSIONS: The high rate (79%) of DPA completion is probably related to individually counseling residents. However, competent residents who despite counseling do not choose to execute a DPA can have detailed advance directives ("living wills") prepared without appointing a decision-maker. 相似文献
108.
Diaphragmatic dysfunction is a common postoperative complication of cardiac surgery in children, with important effects on respiratory morbidity. Its early diagnosis, followed by prompt surgical intervention, has been shown to reduce morbidity. However, the commonest method of diagnosis, based on hemi-diaphragmatic elevation on the chest radiograph, may be less accurate than direct techniques for assessing phrenic nerve function. We have compared electrophysiological and radiological diagnoses of diaphragmatic abnormality in 100 children (aged 3 days to 17.5 yrs) undergoing cardiac surgery, looking at respiratory morbidity as assessed by the duration of ventilation, the time spent on the cardiac intensive care unit (CICU), and the requirement for reintubation. Despite showing good reproducibility, radiological diagnosis was neither sensitive nor specific in identifying patients with electrophysiological phrenic nerve damage. Analysis of the measures of outcome supported the electrophysiological technique. Patients with electrophysiological evidence of damage had a longer duration of ventilation, spent longer on the CICU, and had a greater incidence of reintubation than either radiologically abnormal or "normal" patients. Chest X-rays are not a good method for diagnosing phrenic nerve damage in the early postoperative period in children. If early diagnosis is needed, then direct assessment of phrenic nerve function, such as the measurement of phrenic latency, may be a better technique. 相似文献
109.
Hand function related to age and sex 总被引:1,自引:0,他引:1
After adapting Jebssen's Test of Hand Function to Australian conditions, this study investigated his claim of no significant difference in hand performance among participants younger than 60 years, and determined whether age might be a factor when associated with sex. The method was to test 383 subjects of both sexes in 6 age groups. A 2-factor analysis with age and sex as factors yielded significant differences (p less than 0.01) for "grip strength" "manipulating small objects," and "moving large heavy objects," and indications of significance (p less than 0.05) for "card turning" and "moving large light objects." The sex factor showed males to be significantly better "grip strength," in "moving large heavy objects," and "large light objects," except in the 66-99 age interval where females were significantly better on teh last 2 variables. Females performed better on "writing" and were generally better in "manipulating small objects." These results suggest that the one set of norms given by Jebsen for 60 years and less for each sex, should be replaced by 5 or more, even though the differences were quite small when standard deviations were considered. 相似文献
110.
Halofenate, a serum lipid-lowering agent which inhibits binding of thyroid hormone to thyroxine-binding globulin (TBG), was administered daily for 14 days to 8 hypothyroid subjects with elevated TSH concentrations as a result of incomplete thyroxine (T4) therapy. Drug administration resulted in mean increases in serum dialyzable fraction T4 (DFT4) of 52% over pretreatment levels (P less than 0.01) and in dialyzable fraction triiodothyronine (DFT3) of 26% in 7 subjects, (P less than 0.01). During halofenate treatment in these 7 subjects, serum TSH concentrations decreased significantly (mean = 39%, P less than 0.01) when DFT4 and DFT3 were increased by halofenate. In only two subjects was there a convincing temporal relationship between increased serum absolute free T4 (AFT4) and decreased serum TSH concentrations. Contrary to what would be predicted from the "free hormone hypothesis", changes in serum TSH concentration in these hypothyroid patients appeared to relate primarily to changes in the free fraction of circulating T4 and T3 (DFT4, DFT3), rather than to alterations in AFT4 or AFT3. Halofenate did not alter serum TBG binding capacity. An eighth subject did not show increased DFT4 and DFT3 during halofenate treatment despite achievement of therapeutic serum levels of the agent; in this patient, serum TSH levels rose progressively throughout the period of inadequate T4 replacement and halofenate administration. In hypothyroid patients, short-term halofenate use suggests that the pituitary-thyroid hormone feedback circuit can respond to increases in serum DFT4 and DFT3 in the absence of detactable increases in absolute free hormone concentrations. 相似文献