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81.
82.
The needs of postregistration students pursuing degree-linked clinical courses have received little attention and there are few insights concerning their aspirations when they enrol on such courses. Thus the aim of this study was to explore postregistration students' perceptions of the specific needs of their patient/client group and to examine how they envisaged the course on which they had just enrolled might help them to meet these needs in addition to their own requirements for professional and personal development. Data were collected by group interview from 62 students enrolling on eight different postregistration courses, all employed in an acute hospital trust. The results were analysed inductively. They indicated that students had internalized the state of the healthcare market and were keenly aware of the need to fulfil the expectations of employers and the public, while fulfilling their own needs for education and pursuing their own professional and career trajectories. They appeared ambitious and yet appeared to demonstrate empathy for patients and their families and felt a tremendous desire to provide care of a high quality through the optimal development of technical expertise. Students' emphasis on the importance of keeping abreast of technological developments should not be lightly dismissed considering its prominent position within the acute areas where they were employed, especially as it did not replace their desire to promote the caring aspects of their work.  相似文献   
83.
Two topical controlled-release personal-use arthropod repellent formulations of diethyl methylbenzamide (deet) and permethrin-impregnated clothing were tested on human volunteers in a tropical rain forest near Innisfail, Queensland, Australia. The field trials were arranged in a four-way factorial design which compared fabric types, permethrin treatment and repellent treatments over a 14-hour test period. An analysis of variance with each factor treated as a fixed effect indicated that treatment of the clothing with permethrin and use of topical repellents were effective in preventing bites. The controlled release formulations were not significantly better than the current U.S. Army formulation of deet under field conditions. The repellent formulations and the permethrin-treated clothing used as one system provided better protection than the repellent formulations or permethrin-treated clothing used separately.  相似文献   
84.
Study of movement disorders and brain iron by MR   总被引:2,自引:0,他引:2  
Heavily T2-weighted high-field MR images provide a unique opportunity for the evaluation of the extrapyramidal motor system. The images are affected by the presence of small amounts of naturally occurring paramagnetic substances--principally iron--that delineate the neostriatum (caudate and putamen), globus pallidus, red nucleus, substantia nigra, and dentate nucleus, primarily by a decrease in signal secondary to the T2* effect. Movement disorders are associated with either increased or decreased signal or both in these structures, depending on the pathologic process. In the initial evaluation of 113 patients with a variety of movement disorders, good correlation of imaging abnormalities can be made with a simplified schema of the extrapyramidal pathways and a system of classification of abnormal movements, parkinsonism/tremor, dystonia, chorea, myoclonus, and hemiballismus. Parkinsonisms are characterized by abnormalities of the cortico-ponto-cerebello-dentato-rubro-thalamo-cortico-spinal tract or the nigrostriatal tract. Dystonias are characterized by abnormalities of the neostriatum predominantly affecting the putamen. Choreas are also characterized by abnormalities of the neostriatum but predominantly affecting the caudate nucleus. Hemiballismus is characterized by lesions affecting the subthalamic nucleus or associated pathway.  相似文献   
85.
新缩瞳剂包公藤甲素人工合成研究   总被引:11,自引:0,他引:11  
包公藤甲素是从包公藤(Erycibe obtusifolia Benth.)茎中提得的一个新莨菪烷生物碱,具有强烈的缩瞳作用,临床用于治疗青光眼。本文报道用合成的6β-乙酰氧基托品酮为原料,经卤代、水解、还原和N-去甲基化等反应合成包甲素(8)。经光谱测定证实8与天然包甲素的结构完全一致。合成品系外消旋体,其作用机理与天然品相同,而强度则减半。  相似文献   
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The authors have developed a rapid system for qualitative amino acid analysis by high-pressure liquid chromatography for use in the clinical laboratory. Reverse-phase, linear gradient, high-pressure liquid chromatography of stable dansyl chloride derivatives is accomplished with a C-18 column over 30 minutes, with ultraviolet detection. The resulting chromatograms are compared with template chromatograms that reflect high normal levels of serum and urine amino acids. Large elevations of amino acids associated with inborn errors of metabolism are easily pinpointed, with identification of specific amino acids made by the relative retention times. This technic makes available a rapid and specific qualitative method for investigation of aminoacidopathies and uses versatile and standard liquid chromatography equipment.  相似文献   
89.
The aim of this study was to determine in young, healthy men the relative contribution of pharmacodynamic factors inherent between two groups known to respond differently to hypertensive therapy. Black (n = 10) and white (n = 10) men received an isoproterenol sensitivity test before and after propranolol (0.1 mg/kg, then 50 µg/min). There were greater increases (twofold) in systolic BP following the 1.0- and 1.5-µg isoproterenol dose (P < 0.05) in the black group. During propranolol there were no differences in free (1)-propranolol concentrations between the groups; however, propranolol decreased resting heart rate in the white group more than in the black group (P < 0.05). Cardiac index decreased less in the black group compared to the white group (P < 0.05). Following the second isoproterenol challenge, there again were greater increases in systolic BP in the black group at both the 10- and the 20-µg isoproterenol dose (P < 0.05). Our study has highlighted the importance of cross-racial studies in evaluating drug effects.  相似文献   
90.
Magnetic resonance (MR) imaging was performed on 14 patients with histologically proved osteosarcoma (mean age, 14.4 years). There was excellent correlation of intramedullary tumor extent as determined with MR imaging and pathologic examination (r = 99%). This was facilitated by the presence of a chemical shift artifact at the tumor-marrow interface on the T1-weighted images. The correlation between CT and pathologic findings was not as good (r = 84%). In a single patient, however, a 10-cm length of sclerotic bone was incorrectly interpreted as being tumor. If this case is excluded, the correlation between CT and pathologic findings improves significantly (r = 96%). T2-weighted images were optimal in demonstrating soft-tissue bulk and breach of the epiphysis or cortex. Vascular involvement was also readily defined. The T2 value of the tumor soft-tissue component decreased in patients who were deemed to have responded well to therapy. Two patients with very high T2 values after chemotherapy developed wide-spread metastatic disease and died. Phosphorus-31 MR spectroscopy of five patients with osteosarcoma showed elevated levels of phosphomonoesters (PMEs), inorganic phosphate (Pi), and phosphodiesters (PDEs). PME and PDE peak areas decreased in three patients after chemotherapy, while Pi peak areas increased.  相似文献   
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