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11.
The inverse relationship between smoking and body weight may be due in part to nicotine's effects on reducing hunger and eating. Male smokers and nonsmokers (n=10 each), abstinent overnight from smoking and food, participated in four sessions, involving consumption of a liquid caloric load or water followed by nicotine (15 µg/kg) or placebo via nasal spray every 20 min for 2 h. Hunger and satiety (fullness) ratings were obtained prior to each dose presentation. At the end of the two sessions involving the caloric load (simulating breakfast), subjects were also presented with typical lunch/snack food items varying in sweet taste and fat content for ad lib consumption. Results indicated that, for both smokers and nonsmokers, the hunger-reducing effects of nicotine occurred only following caloric load consumption, and there was no effect of nicotine on hunger after water consumption. Smokers unexpectedly reported greater satiation than nonsmokers following the caloric load regardless of nicotine or placebo condition. Nicotine also resulted in less caloric intake during the meal, and the decrease was not specific to consumption of sweet, high-fat foods. These results indicate that nicotine reduces appetite, possibly helping to explain the influence of smoking on body weight.  相似文献   
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Little is known about smoking patterns of urban American Indians and their interest in quitting. Most published research has focused upon American Indians who live on rural reservations. In this study, personal interviews were conducted with a convenience sample of patients at Urban Indian Health Clinics in four geographically diverse sites: Milwaukee, WI, Minneapolis, MN, and Seattle and Spokane, WA. A total of 419 current smokers and 173 ex-smokers completed interviews. Current smokers reported a median cigarette consumption of 11 per day. Smokers indicated both a moderate desire to quit (mean 5.97, on a scale 0-10) and moderate confidence in their ability to do so (mean 5.56, on a scale 0-10). More than 70 percent of current smokers indicated having previously tried to quit. The most common reasons cited for relapse included craving, social situations, stress, and nervousness. The most common reasons for quitting given by ex-smokers included being "sick" of smoking, health concerns, respiratory problems, and pregnancy. The estimated quit-ratio (former smokers divided by current+former smokers) was 29.7 percent. This quit-ratio, although substantial, is lower than the 45 percent quit-ratio reported for the general U.S. population. Perhaps the most striking findings are the similarities between American Indians and the overall population in both interest in quitting and reasons for doing so. Smoking cessation previously has been viewed as a low priority for this population. The current results suggest the viability of systematic efforts to encourage urban American Indians to quit smoking.  相似文献   
13.
Results from experimental and clinical studies indicate that adjacent nerve roots may be affected in sciatica because of lumbar disc hemiation. This may be caused by proinflammatory mediators in the epidural space being transported into nerve roots at the same or neighboring lumbar segments. The aim of the present study was to investigate the recovery of function of sensory nerve fibers in the adjacent noncompressed nerve roots. Thirty-nine patients undergoing microdiscectomy for monoradiculopathy were investigated with quantitative sensory testing immediately before surgery, and at 6 weeks, 4 months, and 12 months after the operation. Twenty-one healthy volunteers were used as controls. The patients were classified as having a good or a poor result at the 1-year follow-up according to a clinical score. Significant improvement of function in the noncompressed nerve roots were only observed in the 31 patients with a good result. The improvement in small myelinated nerve fibers came within 12 months in the adjacent nerve roots in both the symptomatic as well as the asymptomatic leg. The improvement of function in small unmyelinated fibers also came within 12 months after surgery; however, significant improvement was only observed in the ipsilateral neighboring nerve root. The function in large myelinated fibers did not improve in any of the adjacent nerve roots during the observation period. The observed recovery of function in adjacent noncompressed nerve roots after successful surgical decompression in monoradiculopathy may be because of less production of proinflammatory mediators when the disc herniation is removed.  相似文献   
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15.
The effects of anagrelide on human megakaryocytopoiesis   总被引:2,自引:0,他引:2  
Anagrelide, an inhibitor of platelet aggregation, decreases the number of platelets in normal subjects and in patients with myeloproliferative disorders. We describe studies aimed at discovering the general mechanism(s) by which anagrelide acts. We examined three hypotheses: (1) anagrelide shortens platelet survival, (2) anagrelide inhibits the proliferation of megakaryocytic-committed progenitor cells (CFU-M), and (3) anagrelide inhibits maturation of megakaryocytes. We observed that anagrelide did not shorten platelet survival. Proliferation of CFU-M in vivo was not affected by anagrelide, although high concentrations of anagrelide inhibited CFU-M in vitro . In-vivo and in-vitro anagrelide altered the maturation of megakaryocytes, causing a decrease in their size and changing other morphometric features. We conclude that anagrelide decreases the number of platelets primarily by interfering with the maturation of megakaryocytes.  相似文献   
16.
BACKGROUND: Evidence for the proper management of ischemic heart disease (IHD) in the general population is well established, but recommendations for physical activity and competitive sports in these patients are scarce. The aim of the present paper was to provide such recommendations to complement existing ESC and international guidelines on rehabilitation and primary/secondary prevention. DESIGN AND METHODS: Due to the lack of studies in this field, the current recommendations are the result of consensus among experts. Sports are classified into low/moderate/high dynamic and low/moderate/high static, respectively. RESULTS: Patients with a definitive IHD and higher probability of cardiac events are not eligible for competitive sports (CS) but for individually designed leisure time physical activity (LPA); patients with definitive IHD and lower probability of cardiac events as well as those with no IHD but with a positive exercise test and high risk profile (SCORE > 5%) are eligible for low/moderate static and low dynamic (IA-IIA) sports and individually designed LPA. Patients without IHD and a high risk profile+ a negative exercise-test and those with a low risk profile (SCORE < 5%) are allowed all LPA and competitive sports with a few exceptions. CONCLUSIONS: Individually designed LPA is possible and encouraged in patients with and without established IHD. Competitive sports may be restricted for patients with IHD, depending on the probability of cardiac events and the demands of the sport according to the current classification.  相似文献   
17.
10 healthy volunteers received 200 mg norfloxacin orally every 12 h for 7 days. Saliva, throat and faecal specimens were collected days 0, 3, 5, 7, 14 and 21 to study the effect of norfloxacin on the normal microflora. The concentrations of norfloxacin in serum, urine, saliva and faeces were determined by a microbiological method and all samples except faeces were also assayed by high-pressure liquid chromatography (HPLC). The pharmacokinetics of norfloxacin were studied on day 3. The mean peak serum concentration (+/- SD) attained after 0.75-1.0 h was 0.75 +/- 0.15 mg/l measured by HPLC, and the mean terminal serum half-life was 4.2 +/- 0.6 h. The mean cumulative urinary elimination was 29% during 12 h after dosing. There was no significant difference between values obtained by microbiological assay and by HPLC. The saliva concentration was approximately 30% of the serum levels 1.0-1.5 h after administration. No accumulation in faeces was found during the administration period, and mean concentrations were 940 mg/kg. The changes in the oropharyngeal flora were minor and only branhamella were affected. In the colonic flora, the number of enterobacteria was strongly depressed while the anaerobic microflora was only slightly affected. Two weeks after the administration period, both the oropharyngeal and colonic microflora had returned to normal.  相似文献   
18.
In the endeavour of biobank research there is dispute concerning what type of consent and which form of donor–biobank relationship meet high ethical standards. Up until now, a ‘broad consent'' model has been used in many present-day biobank projects. However it has been, by some scholars, deemed as a pragmatic, and not an acceptable ethical solution. Calls for change have been made on the basis of avoidance of paternalism, intentions to fulfil the principle of autonomy, wish for increased user participation, a questioning of the role of experts and ideas advocating reduction of top–down governance. Recently, an approach termed ‘dynamic consent'' has been proposed to meet such challenges. Dynamic consent uses modern communication strategies to inform, involve, offer choices and last but not the least obtain consent for every research projects based on biobank resources. At first glance dynamic consent seems appealing, and we have identified six claims of superiority of this model; claims pertaining to autonomy, information, increased engagement, control, social robustness and reciprocity. However, after closer examination, there seems to be several weaknesses with a dynamic consent approach; among others the risk of inviting people into the therapeutic misconception as well as individualizing the ethical review of research projects. When comparing the two models, broad consent still holds and can be deemed a good ethical solution for longitudinal biobank research. Nevertheless, there is potential for improvement in the broad model, and criticism can be met by adapting some of the modern communication strategies proposed in the dynamic consent approach.  相似文献   
19.
In response to the need for interprofessional geriatrics education, a half‐day geriatric care boot camp for healthcare professionals was held that covered core concepts in geriatric medicine: delirium and dementia, medication management, palliative care, ethics, and a general overview of older adults. Aspects of the curriculum focused on interprofessional education, and the attendees and presenters were healthcare professionals from a wide variety of fields. Primary objectives were to determine changes in knowledge of core concepts in geriatrics and level of comfort in caring for older adults. Secondary objectives assessed whether participants found the interprofessional approach beneficial and whether they used or shared this information with others in their professional activities. Participants completed pre‐ and postassessment surveys. Changes in participant understanding of each core concept were statistically significant, as was the change in comfort level of participants in caring for older adults. Furthermore, attendees found the multidisciplinary perspective of the boot camp beneficial. A 3‐month follow‐up survey assessed whether attendees applied and shared information learned in their own professional activities. Half of the respondents who reported sharing universally shared core concepts. Delirium and dementia information was most frequently shared. Information was most frequently shared with students, nurses, and patients’ families. Attendees less frequently shared, or did not share, with physicians, physician assistants, social workers, physical and occupational therapists, nutritionists, and dentists. The healthcare professionals who may benefit greatly from future education programs are those with whom the boot camp information was least frequently shared; thus, they are appropriate targets for advertisements for future programs.  相似文献   
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