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41.
BACKGROUND: To adequately address the complex health needs of young people, their access to services, and the quality of services received, must be improved. AIMS: To explore the barriers to service provision for young people and to identify the training needs of primary healthcare service providers in New South Wales (NSW), Australia. DESIGN OF STUDY: A cross-sectional, qualitative study of the perspectives of a range of health service providers. SETTING: A range of primary healthcare organisations across NSW. METHODS: Samples of general practitioners (GPs), youth health workers, youth health coordinators, and community health centre staff were drawn from urban and rural clusters across NSW. Focus groups and interviews were used to identify barriers to service provision and the training needs of service providers. Data were tape recorded, transcribed, and analysed. RESULTS: Barriers to service provision among GPs and community health centre staff included inadequate time, flexibility, skills, and confidence in working with young people, and poor linkages with other relevant services. Training needs included better knowledge of and skills in adolescent health requirements, working with adolescents, and working with other services. Barriers to service provision for youth health workers and coordinators included lack of financial resources and infrastructure. There were few linkages between groups of service providers. CONCLUSION: Models of service provision that allow stronger linkages between service providers, sufficient time for consultation with young people, adequate training and support of health professionals, and flexibility of service provision, including outreach, should be explored and evaluated.  相似文献   
42.
Abstract –  The main objective of this study was to assess the epidemiology of traumatic dental injuries (TDI) to the primary teeth of preschool children and second, to investigate whether TDI were related to anterior open bite and, third, whether TDI are related to socio-economic circumstances in an urban Brazilian population. A clinical examination was performed during the National Day of Children's Vaccination. TDI were classified according to the modified classification proposed by Ellis. In addition to those criteria the presence of tooth discoloration was recorded. An interview was carried out with mothers or guardians. The data collected included mother's level of education and living conditions. The prevalence of TDI was 9.4%. The maxillary central incisors were the most affected teeth. Most children with a TDI experienced traumatic injuries to one tooth (6.3%), while 2.8% had two and 0.4% had three traumatized teeth. The most common crown fracture was in enamel only (68.8%), followed by crown fracture of enamel and dentin (13.8%). Missing teeth following trauma occurred in 10.9% of those with TDI. The prevalence of tooth discoloration was 5.1%. Children with anterior open bite had twice the level the level of TDI compared to those with normal occlusions ( P  = 0.001). Socio-economic factors were not statistically significantly associated with the occurrence of TDI. The prevalence of dental injuries in Brazilian preschool children was low. Children with anterior open bite experienced more dental injuries. Neither of the indicators of socio-economic status was related to the prevalence of TDI.  相似文献   
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To determine whether the third-trimester maternal serum concentration of paraxanthine, caffeine's primary metabolite, is associated with delivery of a small-for-gestational age infant (birth weight less than the 10th percentile for gestational age, gender, and ethnicity) and whether this association differs by smoking, the authors studied 2,515 women who participated in the Collaborative Perinatal Project from 1959 to 1966. The women provided a third-trimester serum sample and had been controls for a nested case-control study of spontaneous abortion. The mean serum paraxanthine concentration was greater in women who gave birth to small-for-gestational age infants (754 ng/ml) than to appropriately grown infants (653 ng/ml, p = 0.02). However, the linear trend for increasing serum paraxanthine concentration to be associated with increasing risk of small-for-gestational age birth was confined to women who also smoked (p = 0.03). There was no association between paraxanthine and fetal growth in nonsmokers (p = 0.48). Adjustment for maternal age, pre-pregnant weight, education, parity, ethnicity, and the number of cigarettes smoked per day did not alter the results substantially, although the p value for trend among smokers increased to 0.07. The authors conclude that maternal third-trimester serum paraxanthine concentration, which reflects caffeine consumption, was associated with a higher risk of reduced fetal growth, particularly among women who smoked.  相似文献   
45.
Summary Levels of dopamine (DA), noradrenaline (NA) and 5-hydroxytryptamine (serotonin, 5-HT) and their metabolites, and the activities of tyrosine hydroxylase (TH), tryptophan hydroxylase (TPH) and monoamine oxidase A and B (MAO-A and MAO-B) have been determined in the rat posterior thalamus after enucleation during postnatal development. DA and 5-HT turnover rate have been measured as 3,4-dihydroxyphenylalanine (DOPA) and 5-hydroxytryptophan (5-HTP) accumulation rates after central decarboxylase inhibition by 3-hydroxybenzylhydrazine (NSD-1015). The major changes were an increase in noradrenergic and serotoninergic metabolism in enucleated animals compared with control animals. A decrease of the MAO-A to MAO-B ratio during postnatal development was found.Abbreviations DA dopamine - DOPAC 3,4-dihydroxyphenylacetic acid - HVA homovanillic acid - DOPA 3,4-dihydroxyphenylalanine - NA noradrenaline - MHPG 3-methoxy-4-hydroxyphenylgly-col - NMN normetanephrine - TRP tryptophan - 5-HTP 5-hydroxytryptophan - 5-HT serotonin - 5-HIAA 5-hydroxy-3-indolacetic acid - TH tyrosine hydroxylase - TPH tryptophan hydroxylase - MAO-A monoamine oxidase-A - MAO-B monoamine oxidase-B Recipients of fellowships from I.I.E. del FISS Reincorporación de doctores y tecnólogos del M.E.C., and Perfeccionamiento de doctores y tecnólogos del MEC, Spain  相似文献   
46.
Postoperative Cognitive Dysfunction in Middle-aged Patients   总被引:13,自引:0,他引:13  
Background: Postoperative cognitive dysfunction (POCD) after noncardiac surgery is strongly associated with increasing age in elderly patients; middle-aged patients (aged 40-60 yr) may be expected to have a lower incidence, although subjective complaints are frequent.

Methods: The authors compared the changes in neuropsychological test results at 1 week and 3 months in patients aged 40-60 yr, using a battery of neuropsychological tests, with those of age-matched control subjects using Z-score analysis. They assessed risk factors and associations of POCD with measures of subjective cognitive function, depression, and activities of daily living.

Results: At 7 days, cognitive dysfunction as defined was present in 19.2% (confidence interval [CI], 15.7-23.1) of the patients and in 4.0% (CI, 1.6-8.0) of control subjects (P < 0.001). After 3 months, the incidence was 6.2% (CI, 4.1-8.9) in patients and 4.1% (CI, 1.7-8.4) in control subjects (not significant). POCD at 7 days was associated with supplementary epidural analgesia and reported avoidance of alcohol consumption. At 3 months, 29% of patients had subjective symptoms of POCD, and this finding was associated with depression. Early POCD was associated with reports of lower activity scores at 3 months.  相似文献   

47.
Intense synaptophysin immunoreactivity was observed around neuronal cell bodies and in the neuropil of the superior cervical ganglion of adult rats. In newborn rats synaptophysin was comparatively less concentrated and restricted to small interstitial spaces. In contrast, in newborns, consistent traces of positivity were found in the Golgi-like area of larger neurons, in agreement with the higher neonatal rate of synaptophysin synthesis. A few clusters of small neurons, numerically more expanded in adult rats, exhibited a dense reaction product filling the whole cytoplasm. No positivity was found in intraganglionic fibres.  相似文献   
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49.
The binding of racemic warfarin, its enantiomers, and several nonsteroidal anti-inflammatory agents to human serum albumin was investigated by equilibrium dialysis at 4 degrees C in pH 7.4 phosphate buffer. The primary binding constant for the S(-) enantiomer of warfarin was approximately two times greater than the corresponding binding of the R(+) enantiomer. The effect of azapropazone, phenylbutazone, naproxen, ibuprofen, mefenamic acid, and tolmetin on the binding of racemic warfarin and its enantiomers was studied. Warfarin was displaced by all of the nonsteroidal anti-inflammatory agents except tolmetin. Azapropazone caused the largest displacement of warfarin (39 to 46% free warfarin versus 2.5 to 6% free warfarin without competing drug), followed by phenylbutazone (23 to 43% free warfarin), naproxen (9 to 24% free warfarin), mefenamic acid (5 to 11.5% free warfarin), and ibuprofen (5 to 9% free warfarin). Azapropazone and phenylbutazone competed with warfarin for the same primary binding site on the albumin molecule. Naproxen appeared to affect warfarin binding at both primary and secondary sites. Ibuprofen and mefenamic acid interfered with the binding of warfarin at its secondary sites. In contrast to the other drugs studied, tolmetin caused an increase in the primary binding constant of warfarin. Structural analysis indicated that a common feature of those compounds which primarily bind at the warfarin site is a hydrophobic area bearing a widely delocalized negative charge.  相似文献   
50.
BACKGROUND: Increased concentrations of very low- (VLDL) and intermediate-density (IDL) lipoproteins in chronic renal failure (CRF) are thought to result from a defect(s) in degradation of plasma triglyceride (TG)-rich lipoproteins. The purpose of this study was to identify lipoprotein abnormalities associated with the reduced lipolytic rate constant, k1, of combined VLDL and IDL substrate from renal patients and asymptomatic controls. METHODS: The VLDL + IDL were isolated from 18 predialytic patients (CRF-I), 8 patients on hemodialysis (CRF-II) and 10 asymptomatic controls. The lipolytic rate constant (k1) of VLDL + IDL was measured by an assay using bovine milk lipoprotein lipase and determination of TG before and after incubation by gas chromatography (GC). Neutral lipids were measured by GC and apolipoproteins by electroimmunoassays; the apolipoprotein-defined TG-rich lipoproteins including Lp-B:C, Lp-B:C:E and Lp-A-II:B:C:D:E were determined by immunoaffinity chromatography. RESULTS: The k1 values of VLDL + IDL were significantly (P < 0.001) lower in CRF-I and CRF-II patients (0.0341 and 0.0352 min-1, respectively) than controls (0.0515 min-1). The levels of apolipoproteins B, C-III and E, and TG-rich Lp-B:C, Lp-B:C:E and Lp-A-II:B:C:D:E particles normalized to 100 mg TG per VLDL + IDL were significantly higher in both groups of CRF patients than in controls. All three TG-rich lipoproteins were characterized by significantly increased percent contents of free (FC) and esterified (CE) cholesterol and a decreased percentage of TG. The k1 values of the combined CRF-I and CRF-II patient groups showed significant negative correlations (P < 0.001) with FC (r=-0.81) and CE (r=-0.63) and a positive correlation with TG (r=0.72). Among lipoprotein particles, only Lp-A-II:B:C:D:E levels showed a significant negative correlation with k1 values (r=-0.47, P < 0.03). CONCLUSIONS: This study shows that the abnormal neutral lipid composition of all three TG-rich lipoprotein particles and increased concentrations of Lp-A-II:B:C:D:E particles represent the main factors affecting the in vitro lipolytic rates of VLDL + IDL substrate in both the CRF patients before dialysis and patients on hemodialysis.  相似文献   
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