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排序方式: 共有1290条查询结果,搜索用时 15 毫秒
71.
Color vision and contrast sensitivity in epilepsy patients treated with initial tiagabine monotherapy 总被引:1,自引:0,他引:1
The purpose of the study was to determine whether the use of a GABAergic antiepileptic drug (AED), tiagabine, affects color vision and contrast sensitivity. Twenty newly diagnosed patients with partial epilepsy (aged 19-72 years), receiving tiagabine as their initial monotherapy for 5-41 months were examined. Color vision was examined with the Standard Pseudoisochromatic Plates 2 (SPP2), with the Farnsworth-Munsell 100 Hue Test (FM100) and with the Color Vision Meter 712 (CVM) anomaloscope. Contrast sensitivity was measured with the Pelli-Robson letter chart. Three patients excluded from the color vision evaluation for congenital red-green color vision defects. Seven out of 17 patients (41%) had acquired color vision deficit examined with the FM100. The CVM anomaloscope revealed minor defects in two patients. Contrast sensitivity function was within normal ranges. The present study suggests that AED therapy with tiagabine, like with other established and newer AEDs may interfere with color perception. 相似文献
72.
Serum tryptase levels in acute coronary syndromes 总被引:2,自引:0,他引:2
Kervinen H Kaartinen M Mäkynen H Palosuo T Mänttäri M Kovanen PT 《International journal of cardiology》2005,104(2):138-143
BACKGROUND: Mast cell accumulation and activation have been demonstrated in the vulnerable shoulder regions of atherosclerotic plaques and at the actual sites of plaque erosion and rupture. When activated and degranulated, mast cells release tryptase, a neutral protease, capable of activating matrix metalloproteinases and predisposing to plaque rupture. We tested the hypothesis that in acute coronary syndromes the levels of serum tryptase would reflect mast cell activation. METHODS AND RESULTS: The study population consisted of 183 patients admitted to the emergency room of 3 general hospitals because of acute chest pain of ischemic origin. Of these patients, 64 suffered from exertional angina presenting with acute chest pain, 60 had unstable angina, and 59 had acute myocardial infarction. Serum tryptase levels were analyzed from samples drawn, on average at 7 h, and also at 24 h after the onset of the chest pain. As controls served 41 patients admitted for surgical treatment of inguinal hernia or varicose veins. Serum tryptase levels remained stable within the observation period, and no differences were detected between the patient groups and controls. On the other hand, the differences in C-reactive protein levels reflected the extent of myocardial injury. CONCLUSIONS: In ACS, serum tryptase levels are normal and remain stable. Our results do not exclude the possibility of local activation of coronary mast cells, but suggest that the excess quantity of tryptase acutely released from mast cells in ACS, if any, is not sufficient to be detected by measuring tryptase concentration in the systemic circulation. 相似文献
73.
Mustonen J Huttunen NP Partanen J Baer M Paakkala A Vapalahti O Uhari M 《The Pediatric infectious disease journal》2004,23(10):959-961
In adults, HLA haplotype B8-DRB1*03 is clearly associated with a severe clinical course of nephropathia epidemica caused by Puumala hantavirus. We investigated whether the same applies in pediatric patients. This HLA haplotype was found in 20 of 39 (51%) of the patients, a significantly higher figure than in the Finnish population (19%). There were, however, no significant differences in the clinical picture between patients with and without HLA B8-DRB1*03. 相似文献
74.
The pharmaceutical industry affects physicians' clinical decision-making, especially their prescribing behaviour. However, little is known of the interactions between medical students and the pharmaceutical industry. The purpose of the present study was to examine the extent and perceived influence of pharmaceutical promotion on Finnish medical students and students' attitudes towards such promotion. Altogether 952 students (34%) responded to an anonymous questionnaire that was distributed to all Finnish medical students at varying levels of study. Students reported that they attended presentations by pharmaceutical company representatives on a frequent basis. A total of 44% attended at least twice a month. Students regarded the pharmaceutical industry as one of their most important sources of pharmaceutical information. The importance attached to pharmaceutical promotion as a source of pharmaceutical information and the intensity of pharmaceutical marketing increased over the course of medical studies. Although most students were not in favour of reducing promotion, the students largely believed that such activities would affect their future prescribing behaviour, and the awareness of this influence increased over the course of studies. The fact that medical students are commonly exposed to pharmaceutical promotion should be addressed in medical education. 相似文献
75.
The development of IgG avidity assays has revolutionised serological diagnosis of Toxoplasma infections. The measurement of IgG avidity has shown its power in various clinical settings, especially in situations where timing and differentiation of primary and secondary infections is crucial. However, no laboratory test performed alone is self-sustained, whereby the diagnostic strategy of choice is sequential (or combinatorial) use of high-quality IgG, IgM, IgA and IgG-avidity assays. The impact of IgG avidity measurement will be discussed in five clinical scenarios: acute acquired infection, primary infection during pregnancy, congenital toxoplasmosis, ocular toxoplasmosis and Toxoplasma infection in immunocompromised patients. All in all in toxoplasmosis, superior diagnostic performance is achieved by appropriate combinations of serological, culture-based and PCR techniques. 相似文献
76.
Partanen AM Kiukkonen A Sahlberg C Alaluusua S Thesleff I Pohjanvirta R Lukinmaa PL 《Toxicology and applied pharmacology》2004,194(1):24-33
Previous studies have shown that 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) can arrest molar tooth development in rats after in utero and lactational exposure, and that the sensitive stage is temporally restricted. To define the stage in which TCDD is able to arrest tooth development and the cellular background of the effect, mouse embryonic molar tooth explants including various early developmental stages from initiation to late cap stage were exposed to TCDD in organ culture. TCDD did not inhibit morphogenesis of the first molar teeth including the early bud-staged E12 first molars, but the teeth were smaller than in control cultures. Accordingly, the second molars underwent morphogenesis in the presence of TCDD when explanted at E15 when they were at the bud stage. TCDD arrested their development when explanted at E14 when they had not yet reached the early bud stage. Immunohistochemical localization of incorporated bromodeoxyuridine in cultured E14 teeth showed that TCDD did not affect cell proliferation. Localization of apoptosis by terminal deoxynucleotidyl transferase (TdT)-mediated nick end labeling (TUNEL) method revealed that TCDD enhanced apoptosis of dental epithelial cells, especially in the dental lamina of both the first and second molars, and in the inner dental epithelium at the cusp tips of the first molars. Thus, TCDD can arrest tooth development in vitro if the exposure starts at the initiation stage, whereas exposure at later stages leads to smaller tooth size and deformation of cuspal morphology. TCDD interferes with tooth development by stimulating apoptosis in those cells of the dental epithelium, which are predetermined to undergo apoptosis during normal development. 相似文献
77.
High-resolution genomic and expression profiling reveals 105 putative amplification target genes in pancreatic cancer 总被引:2,自引:0,他引:2
Mahlamäki EH Kauraniemi P Monni O Wolf M Hautaniemi S Kallioniemi A 《Neoplasia (New York, N.Y.)》2004,6(5):432-439
Comparative genomic hybridization (CGH) studies have provided a wealth of information on common copy number aberrations in pancreatic cancer, but the genes affected by these aberrations are largely unknown. To identify putative amplification target genes in pancreatic cancer, we performed a parallel copy number and expression survey in 13 pancreatic cancer cell lines using a 12,232-clone cDNA microarray, providing an average resolution of 300 kb throughout the human genome. CGH on cDNA microarray allowed highly accurate mapping of copy number increases and resulted in identification of 24 independent amplicons, ranging in size from 130 kb to 11 Mb. Statistical evaluation of gene copy number and expression data across all 13 cell lines revealed a set of 105 genes whose elevated expression levels were directly attributable to increased copy number. These included genes previously reported to be amplified in cancer as well as several novel targets for copy number alterations, such as p21-activated kinase 4 (PAK4), which was previously shown to be involved in cell migration, cell adhesion, and anchorage-independent growth. In conclusion, our results implicate a set of 105 genes that is likely to be actively involved in the development and progression of pancreatic cancer. 相似文献
78.
79.
Liukkonen M Vähätalo K Peltomäki T Tiekso J Happonen RP 《The International journal of adult orthodontics and orthognathic surgery》2002,17(1):41-46
Treatment of dentofacial deformities with jaw osteotomies has an effect on airway anatomy, and therefore, mandibular setback surgery has the potential to diminish airway size. The purpose of this study was to evaluate the long-term effect of mandibular setback surgery on the airway size. The material consisted of pre- and postoperative (minimum 1 year) lateral radiograms of 22 individuals (18 females and 4 males) with a mean age of 30 years, who had undergone mandibular setback surgery to correct skeletal Class III discrepancies. Hard and soft tissue points were digitized with a Numonics Accugrid digitizer and analyzed with Xmetrix software. A paired t test was used to evaluate the difference between pre- and postoperative measurements. In addition, Pearson's coefficient correlation was calculated to reveal the possible association between the skeletal change in relation to the change in airway size. The mean value for the initial SNA was 81.3 degrees, 85.4 degrees for SNB, 36.9 degrees for S-Na/MP, and for the posterior airway, 10.5 mm and 12.0 mm retropalatinally and retrolingually, respectively. At the postoperative evaluation, SNB was 80.7 degrees, S-Na/MP 41.0 degrees, and the posterior airway retropalatinally 8.3 mm and retrolingually 9.8 mm. Statistical analysis revealed a highly significant correlation between the change in the ANB angle and in the S-Na/MP angle versus the change in the upper airway size, both retropalatinally and retrolingually. Mandibular setback surgery with posterior rotation may gradually result in increased upper airway resistance in cases where neuromuscular adaptation is insufficient to compensate for the reduction in the airway size. Therefore, large anteroposterior discrepancies should be corrected by combined maxillary and mandibular osteotomies. 相似文献
80.
Alternative materials to improve total hip replacement tribology 总被引:2,自引:0,他引:2
Santavirta S Böhler M Harris WH Konttinen YT Lappalainen R Muratoglu O Rieker C Salzer M 《Acta orthopaedica Scandinavica》2003,74(4):380-388
An improvement in tribology of bearing surfaces is an effective means of increasing the longevity of total hip replacement (THR). Currently, 3 approaches are available to achieve this aim: first, use of highly cross-linked UHMWPE; second, aluminum oxide ceramic bearings, and third, metal-on-metal bearings. Cross-linking reduces the wear resistance of UHMWPE markedly without impairment of other significant properties of the material. Simulator studies and some clinical long-term (10-22 years) follow-up surveys suggest an almost immeasurable wear of the highly cross-linked UHMWPE-based acetabular components during an expected clinical life span. Bioinert alumina ceramic (aluminum oxide) was introduced 3 decades ago for THR-bearing surfaces to improve performance and longevity. Alumina ceramic is entirely biostable and bioinert and has good mechanical properties. For correctly positioned alumina-on-alumina bearings, the annual linear wear rate has been reported to be 3.9 microm. Alumina heads have been successfully used in combination with polyethylene sockets, but as regards wear, the best results have been obtained with alumina-on-alumina bearings. In ceramic THR bearings, precise manufacture and contact surface geometry, including optimal clearance, are most important. For the currently available products, the component fracture risk is almost nonexistent (less than 1 per 1000). Metal-on-metal bearings were used in the early stage of THR surgery, although not all old designs were successful. More recent analyses of the early series have shown the advantages of metal-on-metal to be better and have led to a renaissance of this articulation. Initially, stainless steel was used because it was easy to manufacture and polish. Current metal-on-metal bearings are based on cobalt-chromium-molybdenum alloys with varying carbon contents. Such bearings are self-polishing. Linear wear rates remain at the level of a few microm a year. An improvement in technology has increased the life span of the above three THR-bearing systems. Although the technical solutions differ considerably, they all seem to improve clearly the tribology and longevity of the THR. Each of these bearing concepts will probably permit the use of larger head sizes, to reduce the risk of impingement and luxations. 相似文献