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131.
The feasibility of using Langmuir-Blodgett films for the lubrication of sputtered thin film magnetic disks has been studied. The results indicate that up to a 40% reduction in the initial friction can be obtained over that attainable typically with unlubricated surfaces. Furthermore, friction build-up and contact stop-start tests also revealed significantly improved performance (on average a factor of 2) compared with conventional (perfluoroether) lubrication. The best results were obtained in the case of SiO2 passivated disks where it is thought that a strong adhesion of the LB coating and substrate could be arranged.  相似文献   
132.
A quasi-static analysis is carried out to examine the capacitive coupling between two nonintersecting orthogonal microstrip lines above a ground plane and in a dielectric substrate. The charge density along the width of each strip is described using a prescribed charge distribution. A pair of coupled integral equations is derived and solved by the method of moments to obtain the excess charge densities. The lumped excess capacitances are computed and compared to those obtained using wire lines with radii equal to the equivalent radii of the strips  相似文献   
133.
A simple moment solution is given for low frequency electromagnetic scattering and radiation problems. The problem is reduced to the corresponding electrostatic and magnetostatic problems. Each static problem is solved using the Method of Moments. The surface of the perfectly conducting scatterer is modeled by a set of planar triangular patches. Pulse expansion functions and point matching testing are used to compute the charge density in the electrostatic problem. For the magnetostatic current a set of charge-free vector expansion functions is used. The problem is formulated assuming the scatterer to be in an unbounded homogeneous region. Scatterers of various shapes, such as the circular disc, the sphere, and the cube are studied. Special attention is paid to a conducting box with a narrow slot. The computed results are the scattered fields, the induced charge and current distributions, and the induced electric and magnetic dipole moments. These are in close agreement with whatever published data are available.  相似文献   
134.
OBJECTIVE: The triglyceride-lowering effects of omega-3 fats and HDL cholesterol-raising effects of exercise may be appropriate management for dyslipidemia in NIDDM. However, fish oil may impair glycemic control in NIDDM. The present study examined the effects of moderate aerobic exercise and the incorporation of fish into a low-fat (30% total energy) diet on serum lipids and glycemic control in dyslipidemic NIDDM patients. RESEARCH DESIGN AND METHODS: In a controlled, 8-week intervention, 55 sedentary NIDDM subjects with serum triglycerides > 1.8 mmol/l and/or HDL cholesterol < 1.0 mmol/l were randomly assigned to a low-fat diet (30% daily energy intake) with or without one fish meal daily (3.6 g omega-3/day) and further randomized to a moderate (55-65% VO2max) or light (heart rate < 100 bpm) exercise program. An oral glucose tolerance test (75 g), fasting serum glucose, insulin, lipids, and GHb were measured before and after intervention. Self-monitoring of blood glucose was performed throughout. RESULTS: In the 49 subjects who completed the study, moderate exercise improved aerobic fitness (VO2max) by 12% (from 1.87 to 2.07 l/min, P = 0.0001). Fish consumption reduced triglycerides (0.80 mmol/l, P = 0.03) and HDL3 cholesterol (0.05 mmol/l, P = 0.02) and increased HDL2 cholesterol (0.06 mmol/l, P = 0.01). After adjustment for age, sex, and changes in body weight, fish diets were associated with increases in GHb (0.50%, P = 0.05) and self-monitored glucose (0.57 mmol/l, P = 0.0002), which were prevented by moderate exercise. CONCLUSIONS: A reduced fat diet incorporating one daily fish meal reduces serum triglycerides and increases HDL2 cholesterol in dyslipidemic NIDDM patients. Associated deterioration in glycemic control can be prevented by a concomitant program of moderate exercise.  相似文献   
135.
BACKGROUND: Chronic myelogenous leukemia (CML) is an indolent but ultimately fatal disease. Because the natural history of CML varies and quality of life with CML may be excellent until shortly before death, deciding whether and when to pursue unrelated donor bone marrow transplantation is often difficult. OBJECTIVE: To compare early transplantation, delayed transplantation, and no transplantation for patients with chronic-phase CML on the basis of discounted, quality-adjusted life expectancy. DESIGN: A markov model comparing different strategies was constructed. This model considers patient age, quality of life, risk aversion, and the competing risks for CML progression and transplant toxicity. SETTING: Therapeutic decision at the time of diagnosis of CML. PATIENTS: The base case is a 35-year-old patient with intermediate-prognosis CML. Younger and older patients with better and worse prognoses are also evaluated. INTERVENTION: Early transplantation, delayed transplantation, and no transplantation. MEASUREMENTS: Quality-adjusted, discounted life expectancy. RESULTS: For patients with newly diagnosed CML, transplantation within the first year provides the greatest quality-adjusted expected survival, although this benefit decreases with increasing patient age. For a 35-year-old patient with intermediate-prognosis CML, transplantation within the first year results in 53 more discounted, quality-adjusted years of life expectancy than does no transplantation. This finding is robust even with varying baseline assumptions. CONCLUSIONS: These results support the use of early unrelated donor bone marrow transplantation for most patients with CML.  相似文献   
136.
A hitherto ignored microvillous cell type, distinct from microvillous supporting cells and other microvillous cell types, was encountered in olfactory and respiratory epithelia of nasal turbinates of rat fetuses, near the transition between these two epithelia. The apex of the cell resembles the apices of vestibular hair cells. The cell has a cone-shaped bundle of microvilli, resembling the complex bundle of hair-cell stereocilia, accompanied by a cilium. Therefore we called this cell type the nasal hair cell. Cilium and microvilli seemed adhered. Cell numbers were very low, up to about 5 per turbinate. The cell's appearance is precocious compared to that of olfactory receptor and supporting cells. Also, while the apices of olfactory receptor and supporting cells and of ciliated respiratory cells underwent major morphological maturation during the developmental period from embryonic day 16 to day 21, the apical structures of the nasal hair cell only changed marginally from embryonic day 16, when they were first seen, through to at least embryonic day 21. The cell's location and precociously mature appearance suggests that it plays a special role in the development of nasal epithelia.  相似文献   
137.
138.
Children are not just small adults. Perioperative nurses working with pediatric patients plan nursing interventions based on established principles of perioperative practice as well as incorporating concepts of growth and development relating to the child. A thorough assessment of the pediatric patient prior to surgery enables the perioperative nurse to plan for the surgical procedure, modifying as need be for the individual patient's specific needs. With adequate preparation, communication, and emotional support, the pediatric surgical experience can be positive for the child, parents, and perioperative team.  相似文献   
139.
Within the pituitary, folliculostellate (FS) cells are considered to regulate the intercellular communication between endocrine cells by paracrine mechanisms. One of the possible paracrine factors involved, could be interleukin-6 (IL-6) which is produced by these cells. Since IL-6 has been shown to be a growth factor of pituitary cells, we have determined whether IL-6 can also influence FS cell proliferation. To test this, a FS cell-like mouse pituitary cell line (TtT/GF cells) was used that exhibits most characteristics of normal FS cells. Under serum-free conditions the proliferation of TtT/GF cells is critically dependent on the initial seeding density: cells seeded at low density do not grow at all whereas cells seeded at high density proliferate with maximal doubling times of 34 hrs. Mouse IL-6 (mIL-6) stimulated only low density cell cultures in a dose and time dependent manner. For cells seeded at high density, exogenously added IL-6 may have failed to stimulate growth because of endogenously produced mIL-6. Conditioned medium from TtT/GF cells, in which mIL-6 concentrations up to 1017 pg/ml were measured, stimulated the proliferation of TtT/GF cells, indicating an autocrine growth stimulatory mechanism. A neutralizing mIL-6 antibody partially suppressed the growth of TtT/GF cells seeded at high density and partially reduced the growth stimulatory activity of TtT/GF conditioned medium. Thus, IL-6 is one but not the only factor that is involved in the autocrine growth stimulatory loop. The relevance of this mechanism for normal FS cells and its physiological consequence needs to be elucidated.  相似文献   
140.
The author indicates the similarity of a human tooth and an endoprosthesis in their action, which is the basis for developing a procedure of endoprosthesis and designing an endoprosthesis with dumping elements. The procedure has been developed during a long-term surgical experiment by examining the results by the following techniques: X-ray, bed testing, light and scanning electron microscope. Experimental results are convincing. For coating the prostheses, polytetrafluoroethylene velour is used in the experiment, but cauflene, the material of the same kind polytetrafluoroethylene, is employed in the clinical setting. The experiments yielded two inventions patented in the Russian Federation. This direction in their development seems to be fruitful in preventing the aseptic endoprosthetic instability that is the most common and severe complication after endoprosthesis and requires most frequently resurgery.  相似文献   
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