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31.
Increasingly, workers have psychological work-related complaints, endangering their work ability and causing considerable economic losses. Many employees consult their general practitioner (GP). He, however, often pays insufficient attention to work-relatedness or to coordination with occupational physicians (OPs). Appropriate guidelines are missing. Consequently, we developed a GP guideline to handle these problems in coordination with OPs, and tested it in a pilot, using an explorative, evaluative study design. 23 GPs were trained to include employed patients and to test the guideline. Patients received questionnaires after 0, 4, 10 and 30 wk, GPs after 4 and 30 wk. The result was a new guideline, regarding problem orientation, diagnosis and advice, meant to avoid contradictory GP-OP advice and to activate patient responsibility. It included a GP-OP-patient communication form concerning information exchange and harmonization of insight/advice. Implementing GPs concluded that the guideline promotes recovery and work resumption and OP-GP contact benefits patients, prevents conflicting advice and promotes agreement on task division. They judged guideline efficiency and OP commitment less positively. Patients were positive, especially about GP-OP contact. Accordingly, an improved guideline, when tested for its effectiveness in a Randomized Controlled Trial, can help GPs to cope with a growing, complex problem, in collaboration with their occupational colleagues.  相似文献   
32.
BACKGROUND: Vending machines account for food sales and revenue in schools. We examined 3 strategies for promoting the sale of lower‐calorie food products from vending machines in high schools in the Netherlands. METHODS: A school‐based randomized controlled trial was conducted in 13 experimental schools and 15 control schools. Three strategies were tested within each experimental school: increasing the availability of lower‐calorie products in vending machines, labeling products, and reducing the price of lower‐calorie products. The experimental schools introduced the strategies in 3 consecutive phases, with phase 3 incorporating all 3 strategies. The control schools remained the same. The sales volumes from the vending machines were registered. Products were grouped into (1) extra foods containing empty calories, for example, candies and potato chips, (2) nutrient‐rich basic foods, and (3) beverages. They were also divided into favorable, moderately unfavorable, and unfavorable products. RESULTS: Total sales volumes for experimental and control schools did not differ significantly for the extra and beverage products. Proportionally, the higher availability of lower‐calorie extra products in the experimental schools led to higher sales of moderately unfavorable extra products than in the control schools, and to higher sales of favorable extra products in experimental schools where students have to stay during breaks. Together, availability, labeling, and price reduction raised the proportional sales of favorable beverages. CONCLUSION: Results indicate that when the availability of lower‐calorie foods is increased and is also combined with labeling and reduced prices, students make healthier choices without buying more or fewer products from school vending machines. Changes to school vending machines help to create a healthy school environment.  相似文献   
33.
The ultrastructural organization of retinal terminals within the nucleus of the optic tract of rabbits was investigated with a combination of anterograde tracing and immunocytochemistry. The anterogradely transported WGA-HRP injected in the vitreous of the eye was visualized with the sensitive gold-substituted silver peroxidase (GSSP) method. Glutamate and GABA immunoreactivity were identified with postembedding colloidal gold particles. Retinal ganglion cell terminals (R-terminals) in the nucleus of the optic tract formed asymmetric synapses and contained spherical vesicles and electron lucent mitochondria. R-terminals were observed in large clusters in the neuropil and in synaptic contact with large initial dendrites and somata. Within the clusters of neuropil the R-terminals formed two types of glomeruluslike arrangements: (1) an R-terminal centrally located and surrounded by small dendritic and axonal profiles and (2) several R-terminals surrounding a single dendrite or a group of dendritic profiles, presumably of interneuronal origin. All R-terminals identified with WGA-HRP as well as those exhibiting similar ultrastructural characteristics showed high levels of glutamate immunoreactivity, but no GABA immunoreactivity. The presence of glutamate and the absence of GABA in R-terminals suggest that glutamate is involved in neurotransmission in the pathway from retina to the nucleus of the optic tract of rabbits.  相似文献   
34.
Antibodies were raised against glycine and they were specific for immunocytochemistry. Obtained from rabbits immunized with glycine conjugated to glutaryled protein-carriers, antisera were then purified by adsorption on the various glutaraldehyde-conjugated protein-carriers. Using a modified ELISA method, their specificity was determined in competition experiments between conjugated glycine and either non-conjugated glycine or other conjugated amino acids or derivatives, preincubated with anti-glycine antibodies. Calculated at half-displacement, the resulting cross-reactivity ratios showed conjugated glycine to be the best recognized compound. By revealing the presence of the majority of the glycine-containing cell bodies in the brainstem and spinal cord, immunocytochemical applications of glycine antibodies confirmed their use as specific tools for a better understanding of the role of glycine in the central nervous system.  相似文献   
35.
36.
Surgery is the treatment of choice in selected patients with hepatic colorectal metastases. Despite improvements in preoperative imaging, patients can undergo unnecessary nontherapeutic laparotomy. The aim of this study was to examine trends in nontherapeutic laparotomy rates in patients undergoing planned surgical therapy for hepatic colorectal metastases. Data from 530 operations (461 patients) undergoing potentially curative surgical therapy for colorectal liver metastases between 1994 and 2005 were analyzed. The incidence of nontherapeutic laparotomy was determined and factors associated with nontherapeutic laparotomy were identified. Overall, 49 nontherapeutic laparotomies were performed (9.2%). Higher nontherapeutic laparotomy rates were seen in patients with multiple metastases and tumor size >5 cm (both P < 0.05). Preoperative positron emission tomography (PET) imaging was associated with lower risk of nontherapeutic laparotomy [5.6% versus 12.4%, P = 0.009, odds ratio (OR) = 0.42]. At laparotomy, extrahepatic findings were the reason for nontherapeutic laparotomy in 44.9% of cases. The nontherapeutic laparotomy rate significantly decreased over time (14.9% for 1994–1997 versus 9.6% for 1998–2001 versus 4.7% for 2002–2005; P = 0.003). While patients in each time period were similar with regard to tumor specific factors, utilization of PET imaging (P < 0.001) as well as resection plus ablation (= 0.004) increased over time. We conclude that prevalence of nontherapeutic laparotomy for patients undergoing surgical exploration for hepatic colorectal metastases has decreased significantly in recent years to less than 5%. The reasons for this trend are probably multifactorial and may include improved preoperative assessment, such as PET imaging, as well as salvage surgical options.  相似文献   
37.
Summary   Purpose: To evaluate the anti-glycolytic effects of 3-BrPA on rats bearing RMT mammary tumors, by determining FDG uptake after intravenous administration of the therapeutic dose. Materials and Methods: Sixteen rats bearing RMT tumors were treated either with 15 mM 3-BrPA in 2.5 ml of PBS or with 2.5 ml of PBS. After treatment, all rats received FDG and were sacrificed 1 h later. Results: 3-BrPA treatment significantly decreased FDG uptake in tumors by 77% (p = 0.002). FDG uptake did not significantly decrease in normal tissues after treatment. Conclusion: Our study showed that 3-BrPA exhibits a strong anti-glycolytic effect on RMT cells implanted in rats. Buijs and Vossen contributed equally to this work.  相似文献   
38.
Schools are overloaded with health promotion programs that, altogether, focus on a broad array of behavioral domains, including substance abuse, sexuality and nutrition. Although the specific content of programs varies according to the domain focus, programs usually address similar concepts: knowledge, attitudinal beliefs, social influences and skills. This apparent conceptual overlap between behaviors and programs provides opportunities for a transfer-oriented approach which will stimulate students to apply the knowledge and skills they have learned in one domain (e.g. skills for resisting tobacco use) to other domains (e.g. alcohol, sex). A requirement for such an approach is that behaviors share at least some determinants. This review addresses this issue by examining similarities between domain-specific determinants of smoking, drinking, safe sex and healthy nutrition among adolescents. Recent empirical studies and reviews were examined. The results show that the following determinants are relevant to all four behaviors: beliefs about immediate gratification and social advantages, peer norms, peer and parental modeling and refusal self-efficacy. Several other determinants have been found to relate to at least two behaviors, e.g. health risk beliefs and parental norms. These results can be used for the development of a transfer-oriented school health promotion curriculum.  相似文献   
39.
Vasopressin, oxytocin, substance P and enkephalin fibers were demonstrated to terminate synaptically in the nucleus of the solitary tract. The detergent Triton X-100 proved to be indispensable for the demonstration of vasopressin and oxytocin while enkephalin and substance P could be visualized very well without it. The differences with respect to morphology between these 4 peptides disappeared when Triton X-100 was used in both groups.  相似文献   
40.
Type II deiodinase (D2) plays a key role in regulating thyroid hormone-dependent processes in, among others, the central nervous system (CNS) by accelerating the intracellular conversion of T4 into active T3. Just like the well-known daily rhythm of the hormones of the hypothalamo-pituitary-thyroid axis, D2 activity also appears to show daily variations. However, the mechanisms involved in generating these daily variations, especially in the CNS, are not known. Therefore, we decided to investigate the role the master biological clock, located in the hypothalamus, plays with respect to D2 activity in the rat CNS as well as the role of one of its main hormonal outputs, i.e. plasma corticosterone. D2 activity showed a significant daily rhythm in the pineal and pituitary gland as well as hypothalamic and cortical brain tissue, albeit with a different timing of its acrophase in the different tissues. Ablation of the biological clock abolished the daily variations of D2 activity in all four tissues studied. The main effect of the knockout of the suprachiasmatic nuclei (SCN) was a reduction of nocturnal peak levels in D2 activity. Moreover, contrary to previous observations in SCN-intact animals, in SCN-lesioned animals, the decreased levels of D2 activity are accompanied by decreased plasma levels of the thyroid hormones, suggesting that the SCN separately stimulates D2 activity as well as the hypothalamo-pituitary-thyroid axis.  相似文献   
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