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41.
Despite the contribution of elevated cholesterol to the developmentof cardiovascular disease, many individuals continue to havecholesterol levels greater than the 5.5 mmol/l recommended bythe Australian National Heart foundation (NHF). Although generalpractitioners appear to be well placed to offer dietary adviceto help patients to reduce their cholesterol levels, there havebeen few if any randomised trials evaluating the effectivenessof general practitioners in this area. A randomised trial ofthe relative effectiveness of two general practitioner programmesin reducing cholesterol levels among patients with cholesterollevels between 5.5 and 7.9 mmol/l was undertaken. The dietaryadvice programme developed by the NHF for use by general practitionerswas compared with minimal advice (feedback on cholesterol level,pamphlet and warning of follow-up). Serum cholesterol was measuredusing a portable Reflotron. At 4-month follow-up, the patientsin the NHF group (n=76) had significantly greater reductionsin cholesterol levels than those in the minimal group (n=70),and a greater proportion of NHF patients had reduced their cholesterolbelow risk levels. On average, the patients in the NHF groupreduced their cholesterol by 0.84 mmol/l or 13.5% of baselinelevels. There were no differences between the NHF and minimalgroup on changes in pre-to post-test body mass index, attitudesor self-reported dietary change and only minimal differencesin satisfaction with advice received.  相似文献   
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An Esophageal and Gastric Approach to Ventricular Pacing   总被引:1,自引:0,他引:1  
Using a unipolar esothoracic pacing system (where current passes from a point source positioned in the distal esophagus to a chest wall pad) and pulse duration of 50 msec, satisfactory 1:1 ventricular capture was obtained in57 (86%) of 66 patients, with a mean threshold current of 27.7 mA at an optimal depth of 40.3 cm from the lower lip. When the unipolar esothoracic and bipolar transesophageal ventricular pacing systems were compared, the bipolar system was associated with a lower success rate and higher threshold current. When unipolar esothoracic pacing and gastrothoracic pacing (where current passes from a point source positioned in the stomach to a chest wall pad) were compared in 23 patients with bradyarrhythmia, ventricular capture was achieved using gastrothoracic pacing in 22 patients (96%) and esothoracic pacing in 21 (91%): gastrothoracic pacing required less current (16.0 mA ± SD 7.2 vs25.8 mA± SD 8.6). Optimal ventricular capture occurred using a unipolar gastrothoracic pacing electrode inserted to an average depth of 44.3 cm together with a high impedance chest pad (250 Ω) placed in the fourth interspace at the left sternal edge, with 50-msec current pulses and a mean threshold of 16.0 mA. Thus, using a gastroesophageal electrode system, ventricular pacing can be achieved successfully, and the availability of such a system could play a major role in resuscitation of patients from severe bradyarrhythmias.  相似文献   
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A child-to-child programme was carried out in six rural schools in Jamaica. School children in grades 4 and 5 were taught concepts of nutrition, environmental and personal hygiene, and child development. The children were encouraged to take messages home to their parents and improve the care of their younger siblings. Four hundred and twenty-three children and 90 mothers and guardians from four of the project schools were evaluated and compared with 199 children and 47 parents from two control schools. The project children showed higher scores on a test of knowledge in the topics at the end of the year. They also improved in some practices at home. The mothers improved in knowledge in some areas but not in their practices. We consider the results sufficiently encouraging to justify incorporating the programme into the country's education curriculum for primary schools.  相似文献   
46.
Eight female members of a family with X-linked chronic granulomatous disease were identified. Five were shown to be carriers of the disease gene. Each of these female carriers of the gene had a history of skin eruptions. The identification of the carrier state is important as genetic counselling should be offered and the prenatal diagnosis of this disorder is possible.  相似文献   
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1 Mono(ADP-ribosyl)transferase activity has been identified on the external surface of human polymorphonuclear neutrophil leucocytes (PMNs). The enzyme is released from the plasma membrane by phosphoinositide-specific phospholipase C, suggesting a glycosylphosphatidylinositol (GPI) linkage of the enzyme to the plasma membrane. Partial sequence of cDNA encoding the enzyme suggests that it is identical to the GPI-linked mono(ADP-ribosyl)transferase identified previously on human skeletal muscle.
2 A panel of inhibitors of mono(ADP-ribosyl)transferase (including vitamins K1 and K3, novobiocin and nicotinamide) showed a rank order of inhibitory potency similar to that described for other mono(ADP-ribosyl)transferases. Furthermore, the mono(ADP-ribosyl)ation of agmatine was inhibited also by diethylamino(benzylidineamino)guanidine (DEA-BAG), another substrate of the enzyme related structurally to arginine.
3 There was a close linear correlation between the I C 50 values for inhibition of mono(ADP-ribosyl)ation of agmatine by DEA-BAG or the enzyme inhibitors and their I C 50 values for inhibition of receptor-dependent polymerization of cytoskeletal actin and chemotaxis.
4 These results suggest a role for mono(ADP-ribosyl)transferase in the transduction pathway involved in receptor-dependent re-alignment of the cytoskeleton during neutrophil chemotaxis.  相似文献   
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Patient management problems (PMP) are being used in medical examinations with increasing frequency despite evidence which throws doubt on their validity as measures of clinical competence. This study investigated the construct validity of a PMP constructed in both written and interview formats. Each test was administered to groups of students of different seniorities and to two groups of Docotor, interns and post-interns. The pattern of scores for the different groups was not that expected of a valid test of competence. The most competent groups (the postinterns) generally scored less well on the calculated indices than the senior students and interns. These findings were similar for both formats of the test so cueing was not thought to be the major factor. It appears that the scoring system is at fault.
A comparison of performance on the written and interview (uncued) formats showed that many more options were chosen by all groups tested on the written PMP.
It was concluded that written PMPs cannot yet be regarded as a valid simulation of clinical performance. Although content validity is high this does not appear to be so for construct validity or concurrent validity.  相似文献   
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