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41.
Susanne Uusitalo PhD MA Jeremy Howick PhD MSc 《Journal of evaluation in clinical practice》2018,24(5):1011-1012
Medical scientists have expressed scepticism about whether philosophy is relevant to medicine. We challenged this in a conference on the topic of “too much medicine” (TMM) held in Oxford in April 2017. The topic of TMM provided an opportunity to bring the two disciplines together because of its history both in philosophy and in medicine. We found that the collaboration between the two disciplines was fruitful when two conditions were met. First, both disciplines had to avoid discipline‐specific jargon. Second, each discipline had to engage with the other. Specifically, medical scientists had to engage with some philosophical literature, and philosophers had to “get their hands dirty with data.” In this conference report, we provide an overview of our discussions and summarize the other papers in the series. 相似文献
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Bhowmik AC Oksala NK Auriko JP Paavonen T Mustonen H Paimela H 《Digestive diseases and sciences》2004,49(9):1526-1530
Several growth factors and cytokines are involved in regulation of the immediate repair of gastrointestinal mucosa, a process also called restitution. Few data exist on the effect of inflammation on this process using an explant model, where the folded basal lamina is included. The aim of the present study was to investigate the effect of simulated inflammation on restitution and on concomitant proliferation and apoptosis in isolated guinea pig gastric mucosa. Paired gastric mucosae were mounted in Ussing chambers (37 degrees C) and a superficial injury was induced (1.25 M NaCl/5 min) followed by a 4-hr restitution (pH 7.3-7.5). During perfusion, simulated inflammation was induced (with 0.5 or 5.0 ng/ml IL-1beta or with activated polymorphonuclear [PMN] cells). The PI (proliferative index) and AI (apoptotic index) are expressed as the number of Mib-1- or Bax-immunopositive cells per 300 foveolar cells, respectively. The mean recovery of electrophysiological resistance of tissues (R) after injury and exposure to serosal IL-1beta during restitution was 95.2 +/- 5.3% (mean +/- SD), whereas the value for control tissues was 89.6 +/- 6.9% (P = 0.016; N = 9). The mean recovery of R in tissues exposured to activated serosal PMN cells during restitution was 97.6 +/- 2.7%, whereas the value for unexposed control tissues was 93.8 +/- 2.9 (P = 0.004; N = 9). The enhancing effect of PMN cells was partially eliminated by serosal anti-ICAM, whereas serosal cytochalasin D abolished the process completely. The PI of tissues exposed to serosal PMN cells was 34.6 +/- 17.3, whereas the value for unexposed controls was 24.7 +/- 15.5 (P = 0.04; N = 5). The corresponding AI values were 17.0 +/- 2.8 and 12.0 +/- 5.7, respectively (NS; N = 4). Simulated inflammation either with serosal IL-1beta or with activated PMN cells enhances restitution and proliferation, whereas their effect on AI is only suggestive. Exogenous serosal anti-ICAM modulates restitution, whereas cytochalasin D abolishes it completely, suggesting that the structural signaling system including focal adhesions and cytoskeleton plays a significant role in the regulation of restitution. 相似文献
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OBJECTIVE: To study the impact of 24 months of strength training on the physical function of patients with early rheumatoid arthritis (RA). METHODS: Seventy patients were assigned to either the strength training (experimental) group (n = 35) or the control group (n = 35). Patients in the experimental group performed strength training for 24 months, and control patients were instructed to perform range of motion exercises. Maximal strength of the knee extensors, trunk flexors, and extensors, as well as grip strength were recorded with dynamometers. Disease activity was assessed by the erythrocyte sedimentation rate and Ritchie's articular index, joint damage was determined by the Larsen x-ray index, and functional capacity was assessed using the Valpar 9 test and the Stanford Health Assessment Questionnaire (HAQ). The employment status of each patient was recorded. RESULTS: In the experimental group, strength training led to significant increases (19-59%) in maximal strength of the trained muscles. Such increases in the control group varied from 1% to 31%. There was a clear training effect on muscular strength in favor of the experimental group, but significant improvements in the HAQ indices as well as in the Valpar 9 test were seen also in control patients. Results of the Valpar 9 and the HAQ were statistically significantly better in patients who remained gainfully employed compared with patients who retired preterm during followup. However, compared with patients who remained in the work force, patients who retired were older, and their work was physically more demanding. CONCLUSION: As expected, strength training led to increased muscle strength, but this increase did not correlate with improved physical function as assessed by the Valpar 9 work sample test. The increased muscle performance did not prevent a substantial proportion of patients from retiring preterm. The 2 items from the Valpar 9 test that were applied were not sensitive enough to differentiate the patients according to their working status. 相似文献
45.
Expression of von Hippel-Lindau tumor suppressor and tumor-associated carbonic anhydrases Ⅸ and Ⅻ in normal and neoplastic colorectal mucosa 总被引:1,自引:0,他引:1
46.
Effects of long-term estrogen replacement therapy versus combined hormone replacement therapy on nitric oxide-dependent vasomotor function 总被引:6,自引:0,他引:6
Jokela H Dastidar P Rontu R Salomäki A Teisala K Lehtimäki T Punnonen R 《The Journal of clinical endocrinology and metabolism》2003,88(9):4348-4354
Postmenopausal hormone replacement therapy (HRT) with estrogen may increase production of the predominant endothelium-derived vasodilator nitric oxide (NO) and consequently improve vascular reactivity. In contrast, concurrent progestin therapy may oppose this beneficial effect. We studied the effect of long-term estrogen HRT and combined HRT on vasomotor function and on plasma nitrate, which reflects the amount of NO in the circulation. As lipid peroxidation affects NO production and impairs endothelial function, we also measured the amount of the in vivo lipid peroxidation marker urinary 8-iso-prostaglandin F(2 alpha). The study group comprised 15 women receiving estradiol valerate HRT (mean age, 56 yr; treatment duration, 10.5 yr) and 15 women receiving combined HRT with estradiol valerate and levonorgestrel (mean age, 58 yr; treatment duration, 11.3 yr). The peak flow velocity (PFV) and pulsatility index of the common carotid and internal carotid artery and the abdominal aorta were measured by ultrasonography after long-term HRT (baseline), after a 4-wk pause and again 3 wk after reintroducing HRT. A statistically significant interaction between the groups and time points was observed in the PFV of the internal carotid artery (P = 0.011). In women taking estradiol valerate, the PFV values decreased significantly after withdrawal of HRT (P = 0.007) and increased again to the baseline level after reintroduction of therapy (P < 0.001). In women receiving combined HRT, the PFV remained stable over all study periods. At baseline, the PFV of women taking estradiol valerate correlated with the plasma nitrate concentration in the common carotid artery (r = 0.646; P = 0.009) and in the abdominal aorta (r = 0.579; P = 0.024). For pulsatility index and urinary 8-iso-prostaglandin F(2 alpha) excretion, there were no significant differences between the groups. Our results suggest that the favorable effects of long-term estrogen treatment on blood flow are at least partly mediated through NO. The addition of levonorgestrel to the treatment regimen appears to abolish this effect. 相似文献
47.
Frequency of hereditary nonpolyposis colorectal cancer 总被引:10,自引:0,他引:10
Jukka-Pekka Mecklin M.D. Heikki J. Järvinen M.D. Antti Hakkiluoto M.D. Hannu Hallikas M.D. Kari-Matti Hiltunen M.D. Niilo Härkönen M.D. Ilmo Kellokumpu M.D. Seppo Laitinen M.D. Jari Ovaska M.D. Jukka Tulikoura M.D. Erkki Valkamo M.D. 《Diseases of the colon and rectum》1995,38(6):588-593
PURPOSE: Hereditary nonpolyposis colorectal cancer (HNPCC) is an autosomal dominant cancer syndrome characterized by early onset of colorectal carcinomas (CRC). Recently, two HNPCC genes have been mapped and cloned, one in the short arm of chromosome 2 and another in the short arm of chromosome 3. There has been a major controversy about the frequency of HNPCC. The few estimates available have been based on series selected by age or series representing local area. The purpose of the present study was to design a nonselected, prospective, multicenter study, taking into account the family background and other risk factors of CRC. METHODS: The proportion of HNPCC of all (N=406) CRC cases was evaluated in a prospective multicenter study. Family history and other risk factors were investigated over a 12-month period for all new CRC patients in ten hospitals. These cases constituted 23 percent of all CRCs diagnosed in Finland during the study period. RESULTS: Three (0.7 percent) cases of verified and seven (1.7 percent) cases of suspected HNPCC were identified, following the evaluation of all families with features indicative of susceptibility to cancer. The proportion of identifiable risk factors of CRC was 5.8–7.5 percent (HNPCC, 0.7-2.4 percent; previous CRC, 3.4 percent; ulcerative colitis, 1.0 percent; familial adenomatous polyposis coli, 0.7 percent). CONCLUSION. This prospective multicenter study revealed that the frequency of hereditary colorectal cancer is lower than in some previous studies, when diagnosis is based on extensive pedigree analysis. This result with recent findings of common ancestral founding mutation in Finnish HNPCC families indicates that there may be geographic differences in the occurrence of HNPCC. However, this does not change the fact that identification of HNPCC—perhaps one of the most common inherited diseases identified in humans—has become a question of vital importance now when diagnosis of the syndrome and largescale screening of gene carriers using specific tests are on the horizon.Supported by grants from the Finnish Cancer Society, the Finnish Foundation for Gastroenterological Research, the Sigrid Juselius Foundation, and the Academy of Finland, Helsinki, Finland. 相似文献
48.
Anne S. Koponen Juha E. Peltonen Marja K. Päivinen Jyrki M. Aho Harriet J. Hägglund Arja L. Uusitalo Harri J. Lindholm Heikki O. Tikkanen 《European journal of applied physiology》2013,113(5):1181-1188
Blood O2 carrying capacity affects aerobic capacity (VO2max). Patients with type 1 diabetes have a risk for anaemia along with renal impairment, and they often have low VO2max. We investigated whether total haemoglobin mass (tHb-mass) and blood volume (BV) differ in men with type 1 diabetes (T1D, n = 12) presently without complications and in healthy men (CON, n = 23) (age-, anthropometry-, physical activity-matched), to seek an explanation for low VO2max. We determined tHb-mass, BV, haemoglobin concentration ([Hb]), and VO2max in T1D and CON. With similar (mean ± SD) [Hb] (144 vs. 145 g l?1), T1D had lower tHb-mass (10.1 ± 1.4 vs. 11.0 ± 1.1 g kg?1, P < 0.05), BV (76.8 ± 9.5 vs. 83.5 ± 8.3 ml kg?1, P < 0.05) and VO2max (35.4 ± 4.8 vs. 44.9 ± 7.5 ml kg?1 min?1, P < 0.001) than CON. VO2max correlated with tHb-mass and BV both in T1D (r = 0.71, P < 0.01 and 0.67, P < 0.05, respectively) and CON (r = 0.54, P < 0.01 and 0.66, P < 0.001, respectively), but not with [Hb]. Linear regression slopes were shallower in T1D than CON both between VO2max and tHb-mass (2.4 and 3.6 ml kg?1 min?1 vs. g kg?1, respectively) and VO2max and BV (0.3 and 0.6 ml kg?1 min?1 vs. g kg?1, respectively), indicating that T1D were unable to reach similar VO2max than CON at a given tHb-mass and BV. In conclusion, low tHb-mass and BV partly explained low VO2max in T1D and may provide early and more sensitive markers of blood O2 carrying capacity than [Hb] alone. 相似文献
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Analysis of lapine cartilage matrix after radiosynovectomy with holmium-166 ferric hydroxide macroaggregate 总被引:2,自引:0,他引:2 下载免费PDF全文
Mäkelä OT Lammi MJ Uusitalo H Hyttinen MM Vuorio E Helminen HJ Tulamo RM 《Annals of the rheumatic diseases》2003,62(1):43-49
OBJECTIVE: To study the short and long term effects of radiosynovectomy on articular cartilage in growing and mature rabbits. METHODS: The articular cartilage of the distal femurs of rabbits was examined four days, two months, and one year after radiosynovectomy with holmium-166 ferric hydroxide macroaggregate ([(166)Ho]FHMA). Arthritic changes were evaluated from histological sections by conventional and polarised light microscopy, and glycosaminoglycan measurements using safranin O staining, digital densitometry, and uronic acid determination. Proteoglycan synthesis was studied by metabolic [(35)]sulphate labelling followed by autoradiography, and electrophoretic analysis of extracted proteoglycans. Northern analyses were performed to determine the mRNA levels of type II collagen, aggrecan, and Sox9 in cartilage samples. RESULTS: Radiosynovectomy had no major effect on the histological appearance of articular cartilage in mature rabbits, whereas more fibrillation was seen in [(166)Ho]FHMA radiosynovectomised knee joints of growing rabbits two months after treatment, but not after one year. Radiosynovectomy did not cause changes in the glycosaminoglycan content of cartilage or in the synthesis or chemical structure of proteoglycans. No radiosynovectomy related changes were seen in the mRNA levels of type II collagen, whereas a transient down regulation of aggrecan and Sox9 mRNA levels was seen in young rabbits two months after [(166)Ho]FHMA radiosynovectomy. CONCLUSIONS: [(166)Ho]FHMA radiosynovectomy caused no obvious chondrocyte damage or osteoarthritic changes in mature rabbits, but in growing rabbits some transient radiation induced effects were seen--for example, mild cartilage fibrillation and down regulation of cartilage-specific genes. 相似文献