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101.
This article explores the relation of age to manifestations and antecedents of attitude strength. Three studies demonstrate that susceptibility to attitude change is greater during early and late adulthood than during middle adulthood. Three additional studies demonstrate that attitude importance, certainty, and perceived quantity of attitude-relevant knowledge are greater in middle adulthood than during early or late adulthood. These antecedents may therefore explain life cycle shifts in susceptibility to change. Susceptibility to change, importance, certainty, and perceived knowledge differ from one another in terms of their correlations with education, gender, and race, challenging the notion that attitude strength is a unitary construct. Evidence that people incorrectly believe that susceptibility to change declines steadily over the life course reinforces the distinction between operative and meta-attitudinal measures of attitude strength.  相似文献   
102.
OBJECTIVE: To provide an overview of the knowledge base concerning the prescribing of psychotropic agents in young children with mental disorder and related mental health problems. METHOD: Relevant information is reviewed concerning the knowledge base available to inform pediatric psychopharmacology prescribing practices. RESULTS: Very few psychoactive medications have been adequately tested for safety and efficacy in young children, despite relatively high rates of prescribing. CONCLUSION: Behavioral and psychotherapeutic strategies are often the wisest first therapeutic intervention for this age group. Psychotropic medications may be required, but should be used cautiously in young children, while additional studies are being conducted.  相似文献   
103.
CD14 is a glycosylphosphatidylinositol (GPI)-anchored membrane glycoprotein which functions as a receptor on myeloid cells for ligands derived from microbial pathogens such as lipopolysaccharide (LPS). We have studied the importance of the GPI tail of CD14 in signalling with the promonocytic cell line THP-1 expressing recombinant CD14 in a GPI-anchored form (THP1-wtCD14 cells) or in a transmembrane form (THP1-tmCD14). We found that, like other GPI-anchored molecules, GPI-anchored CD14 was recovered mainly from a Triton X-100-insoluble fraction, whereas transmembrane CD14 was fully soluble in Triton X-100. LPS induced cell activation of THP1-wtCD14 and of THP1-tmCD14 (protein tyrosine kinase phosphorylation, NF-kappaB activation, and cytokine production) in a very similar manner. However, anti-CD14 antibody-induced cross-linking caused a rapid calcium mobilization signal only in GPI-anchored CD14 cells. Studies with pharmacologic inhibitors of intracellular signalling events implicate phospholipase C and protein tyrosine kinases in the genesis of this antibody-induced calcium signal. Our results suggest that GPI anchoring and CD14 targeting to glycolipid-rich membrane microdomains are not required for LPS-mediated myeloid cell activation. GPI anchoring may however be important for other signalling functions, such as those events reflected by antibody cross-linking.  相似文献   
104.
Circadian clocks are complex biochemical systems that cycle with a period of approximately 24 hours. They integrate temporal information regarding phasing of the solar cycle, and adjust their phase so as to synchronize an organism's internal state to the local environmental day and night. Nocturnal light is the dominant regulator of this entrainment. In mammals, information about nocturnal light is transmitted by glutamate released from retinal projections to the circadian clock in the suprachiasmatic nucleus of the hypothalamus. Clock resetting requires the activation of ionotropic glutamate receptors, which mediate Ca2+ influx. The response induced by such activation depends on the clock's temporal state: during early night it delays the clock phase, whereas in late night the clock phase is advanced. To investigate this differential response, we sought signalling elements that contribute solely to phase delay. We analysed intracellular calcium-channel ryanodine receptors, which mediate coupled Ca2+ signalling. Depletion of intracellular Ca2+ stores during early night blocked the effects of glutamate. Activators of ryanodine receptors induced phase resetting only in early night; inhibitors selectively blocked delays induced by light and glutamate. These findings implicate the release of intracellular Ca2+ through ryanodine receptors in the light-induced phase delay of the circadian clock restricted to the early night.  相似文献   
105.
Selective serotonin reuptake inhibitors (SSRIs) have become the agents of first choice in the treatment of depression because of their safe side effect profile. This paper reviews the current literature on the use of SSRIs in pregnancy and lactation concerning their safety. There are human studies that only used fluoxetine in pregnancy, which established its safety. SSRIs are excreted in breast milk, and their long-term effects on the newborn are unknown at this time. The decision to use SSRIs in pregnancy should be made on a case by case basis with active involvement of the patient in the informed consent process during which the risks and benefits are discussed and documented.  相似文献   
106.
107.
A survey of radiation doses to children from diagnostic radiography has been carried out in a dedicated paediatric X-ray room. Entrance surface dose (ESD) and dose-area product (DAP) per radiograph were simultaneously measured with thermoluminescent dosemeters (TLDs) and a DAP meter to provide mean dose values for separate age ranges. Results of ESD and DAP were lower than the mean values from other UK studies for all ages and radiographs, except for the infant pelvis AP radiograph. Comparison of ESD and radiographic technique with CEC quality criteria highlighted a need for reduction of dose to infants and implied an increase in tube filtration might overcome the limitations of the room's three-phase, 12-pulse generator, allowing higher tube potentials to be used on infants. Additional tube filtration of 3 mmA1 was installed following assessment of dose reduction and image quality with test objects and phantoms, and confirmation from the paediatric radiologist that clinical image quality was not-significantly altered. The tube potential was increased from 50 to 56 kVp for the infant pelvis AP radiograph. The resulting ESD and effective dose fell by 51% and 38%, respectively. The CEC quality criteria have proved useful as a benchmark against which technique in X-ray departments can be compared, and as such are a useful tool for optimizing radiographic technique and reducing patient dose.  相似文献   
108.
Curcumin, a natural yellow colourant from turmeric, is insoluble in water. It has been rendered water-soluble by preparation of suitable amino acid derivatives. Several amino acid conjugates of curcumin were synthesised in high yields (45–76%). These curcumin derivatives were soluble in water at 1–10 mg/ml concentrations. Derivatives of curcumin with alkyl-substituted amino acids, such as alanine, valine, serine and cysteine, exhibited smaller IC50 values (∼50%) than did curcumin in antioxidant assays. With respect to antimutagenicity against Salmonella typhimurium TA 98 and TA 1531, the derivatives showed an effect stronger than or, in a few cases, similar to curcumin. These results clearly demonstrated that the conjugation of curcumin at the phenolic position with amino acids, while rendering the molecule water-soluble, led to the improvement of several of its in vitro biological attributes, the effect being more pronounced in the case of specific alkyl-substituted amino acids.  相似文献   
109.
BACKGROUND: Experimental protocol in our laboratory routinely requires the precise placement of instruments at, or near, the retina. Although manipulators for placing an instrument within the eye presently exist, none of the designs were satisfactory due to limitations on size, accuracy and operability. To overcome these limitations, we have developed a novel six degree of freedom manipulator designed specifically for retinal microsurgery. METHODS: The manipulator is parallel in structure and provides submicrometer positioning of an instrument within the constrained environment of the eye. The position of an instrument attached to the manipulator is commanded by the operator using a hand-held trackball. A computer controller interprets the trackball input and moves the manipulator in an intuitive manner according to mathematically constrained modes of operation. RESULTS: Over 50 retinal vessels in the live, anesthetized cat have been successfully cannulated for pressure measurement and drug injection using the described manipulator and micropuncture techniques. The targeted vessels ranged in internal diameter from 20 to 130 microns. CONCLUSION: This device has applications in microsurgery where tremor and fatigue limit the performance of an unaided hand and where mechanically constrained manipulators are inappropriate due to size and operative constraints.  相似文献   
110.
The aim of this study was to evaluate psychosocial quality of life after heart transplantation. We examined 29 patients (25 M and 4 F), average age was 43.5 y (18-62 y). The age at time of heart transplantation was 43 years (17-55 y). The time after heart transplantation was 3.3 year (0.3-9 y). Spielberger's Questionnaire of Anxiety, Knobloch's inventory of neuroticism, Freiburg's Personality Inventory and Quality of Life Inventory were used, 33% of patients demonstrated increasing frequency and 29% of patients increasing intensity of neurotic symptoms. 23% of patients presented increasing levels of anxiety (as a state). The personality dimensions (depression, excitability and low emotional stability) displayed high frequency. The results showed that patients were more satisfied with family support, with sexual activities, and less satisfied with financial situation, social activities, social isolations, sleep, memory, excitability, fatigue. 41.5% of patients returned back to work. The results indicate that these psychosocial factors play an important role in quality of life after heart transplantation. That is why if is necessary to dedicate an increasing attention to them. (Tab. 1, Fig. 6, Ref. 14.)  相似文献   
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