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101.
Poor adherence to treatment is well recognized and contributes significantly to treatment failures in medical care. Studies examining contributing factors have focused predominantly on the patient. Studies examining provider influences have primarily examined communication styles or educational practices. M. R. DiMatteo et al (see record 1993-26883-001) show that other characteristics of the provider may influence patient behavior. Particularly interesting is the finding that baseline adherence predicts adherence 2 yrs later. Although this study opens the door to an examination of provider characteristics and their influence on patient behavior, care needs to be taken to avoid too rapid an acceptance of the discrete findings. The study used self-report by interview, a measure that can be significantly biased. However, this study provides future avenues to explore using more objective measures of patient adherence. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
102.
Md. Mahiuddin Talukdar Jacqueline Plaizier-Vercammen 《Drug development and industrial pharmacy》1993,19(9):1037-1046
Xanthan gum was evaluated as hydrophilic matrix for controlled release preparations. Different parameters were considered: direct and wet granulation, gum concentration, effect of addition of binders, pH, ionic strength, rotation speed and surfactant. Suitable controlled release profile could be obtained. Practically no influence of the parameters studied was noted, with the exception of gum concentration, the rotation speed and presence of ion in the dissolution medium. The release rate profiles were evaluated by different kinetic equations: Zero order, First order, Higuchi equation and RRSBW equation and the data statistically analyzed with F-Ratio. Without binder, in aqueous medium, zero order kinetics were found from the origin of the release rate profile. With binder and dissolution media with electrolytes or buffer solutions, generally zero order kinetics were also found after an initial period of about half an hour. The release kinetics were independent of the method of preparation and compression force. 相似文献
103.
Male and female weanling rats were fed diets containing 2 or 42% of calories as corn oil or 40% as beef tallow plus 2% as
corn oil until they were 12 or 18 weeks of age. Incorporation of C14-acetate into lipids of serum and liver and concentration of lipids in serum, liver, and carcass at the end of these periods
were determined.
Net synthesis of noncholesterol lipid was repressed by changing the diet from 2% to 42% of calories from either dietary fat
in both sexes and at both ages. Cholesterol net synthesis was enhanced 29-fold in males and 22-fold in females fed 42% corn
oil compared to 2% corn oil to the age of 12 weeks. It was enhanced only 2.6-fold for males and 3.4-fold for females by 40%
beef tallow plus 2% corn oil. At 18 weeks of age cholesterol synthesis in males fed 42% corn oil was 7.3 and in females 9.1
times the value for those fed 2% corn oil. At this age the values for rats fed 40% beef tallow plus 2% corn oil were 1.2 and
3.7 times those for 2% corn oil fed rats of the respective sexes. 相似文献
104.
105.
A subnanosecond voltage generator has been used to measure the zero-strain electro-optic coefficient r63? of KD*P, and a value of 24.0×10?12 m/V±5% has been obtained. 相似文献
106.
Pulsed-laser damage in XDP electro-optic crystals, occurring at energy densities ? 2J/cm2, has been related to the presence of micrometer-sized inclusions. For material free of these inclusions damage occurs by self-focusing mechanisms at power densities of approximately 20GW/cm2. 相似文献
107.
National seatbelt observation surveys indicate commercial vehicle drivers' seatbelt usage is lower than passenger vehicle drivers. Seatbelts are effective at preventing injuries and death following motor vehicle crashes and an important component in decreasing morbidity and mortality related to commercial vehicle crashes. We conducted an observation survey of heavy commercial vehicle drivers' seatbelt usage to gather baseline data and to aid in planning prevention programs. We found that the observed heavy commercial vehicle drivers had a seatbelt usage rate of 64%, approximately 20% lower than the national rate for drivers of passenger vehicles. Our observations demonstrate a need to increase seatbelt usage among heavy commercial vehicle drivers. Specific programs and resources for intervention programs targeting heavy commercial vehicle drivers are warranted. 相似文献
108.
Fleming C Long DL McMillan N Johnston J Bovet N Dhanak V Gadegaard N Kögerler P Cronin L Kadodwala M 《Nature nanotechnology》2008,3(4):289-233
Transition metal oxides exhibit a rich collection of electronic properties and have many practical applications in areas such as catalysis and ultra-high-density magnetic data storage. Therefore the development of switchable molecular transition metal oxides has potential for the engineering of single-molecule devices and nanoscale electronics. At present, the electronic properties of transition metal oxides can only be tailored through the irreversible introduction of dopant ions, modifying the electronic structure by either injecting electrons or core holes. Here we show that a molybdenum(VI) oxide 'polyoxometalate' molecular nanocluster containing two embedded redox agents is activated by a metallic surface and can reversibly interconvert between two electronic states. Upon thermal activation two electrons are ejected from the active sulphite anions and delocalized over the metal oxide cluster cage, switching it from a fully oxidized state to a two-electron reduced state along with the concomitant formation of an S-S bonding interaction between the two sulphur centres inside the cluster shell. 相似文献
109.
We describe a general method to integrate DNA strands between single-walled carbon nanotube electrodes and to measure their electrical properties. We modified DNA sequences with amines on either the 5' terminus or both the 3' and 5' termini and coupled these to the single-walled carbon nanotube electrodes through amide linkages, enabling the electrical properties of complementary and mismatched strands to be measured. Well-matched duplex DNA in the gap between the electrodes exhibits a resistance on the order of 1 M(Omega). A single GT or CA mismatch in a DNA 15-mer increases the resistance of the duplex approximately 300-fold relative to a well-matched one. Certain DNA sequences oriented within this gap are substrates for Alu I, a blunt end restriction enzyme. This enzyme cuts the DNA and eliminates the conductive path, supporting the supposition that the DNA is in its native conformation when bridging the ends of the single-walled carbon nanotubes. 相似文献
110.