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排序方式: 共有1296条查询结果,搜索用时 15 毫秒
21.
N. Hutri-Kähönen Mika Kähönen Pasi Jolma Xiumin Wu Juhani Sand Isto Nordback Pauli Ylitalo Pertti Arvola Ilkka Pörsti 《Naunyn-Schmiedeberg's archives of pharmacology》1999,359(4):322-330
The majority of the findings concerning arterial physiology and pathophysiology originate from studies with experimental
animals, while only limited information exists about the functional characteristics of human arteries. Therefore, the aim
of the present work was to compare the control of vascular tone in vitro in mesenteric arterial rings of corresponding size
(outer diameter 0.75–1 mm) from humans and Wistar-Kyoto rats. The relaxations to acetylcholine (ACh) were clearly less marked
in the mesenteric arteries of humans when compared with rats. How-ever, when calcium ionophore A23187 was used as the vasodilator,
the endothelium-mediated relaxations did not significantly differ between these species. The NO synthase inhibitor N
G-nitro-l-arginine methyl ester (l-NAME) attenuated the relaxations to ACh and A23187 in both groups. The endothelium-independent
relaxations to the β-adrenoceptor agonist isoprenaline and the nitric oxide (NO)-donor nitroprusside were somewhat lower in
human arteries, while vasodilation induced by the K+ channel opener cromakalim was similar between humans and rats. Arterial contractile sensitivity to noradrenaline and serotonin
was slightly lower in human vessels, whereas contractile sensitivity to KCl was similar between these species. The contractions
induced by cumulative addition of Ca2+ with noradrenaline as the agonist were effectively inhibited in both groups by the calcium channel blocker nifedipine, the
effect of which was clearly more pronounced in human arteries. In conclusion, the control of vascular tone of isolated arteries
of corresponding size from humans and rats appeared to be rather similar. The most marked differences between these species
were the impaired endothelium-mediated dilation to ACh and the more pronounced effect of nifedipine on the Ca2+-induced contractions in human arteries.
Received: 1 October 1998 / Accepted: 4 January 1999 相似文献
22.
Juha Juntunen Juhani Huuskonen Krista Laine Riku Niemi Hannu Taipale Tapio Nevalainen David W Pate Tomi J?rvinen 《European journal of pharmaceutical sciences》2003,19(1):37-43
Phosphate esters of arachidonylethanolamide (AEA) and R-methanandamide were synthesized and evaluated as water-soluble prodrugs. Various physicochemical properties (pK(a), partition coefficient, aqueous solubility) were determined for the synthesized phosphate esters. The chemical stability of phosphate esters was determined at pH 7.4. In vitro enzymatic hydrolysis rates were determined in 10% liver homogenate, and in a pure enzyme-containing (alkaline phosphatase) solution at pH 7.4. The intraocular pressure (IOP) lowering properties of R-methanandamide phosphate ester were tested on normotensive rabbits. The phosphate promoiety increased the aqueous solubility of the parent compounds by more than 16500-fold at pH 7.4. Phosphate esters were stable in buffer solutions, but rapidly hydrolyzed to their parent compounds in alkaline phosphatase solution (t(1/2)<15 s) and liver homogenate (t(1/2)=8-9 min). The phosphate ester of R-methanandamide reduced IOP in rabbits. These results indicate that the phosphate esters of AEA and R-methanandamide are useful water-soluble prodrugs. 相似文献
23.
Tiina Tyni Juhani Rapola Anders Paetau Aarno Palotie Helena Pihko 《Fetal and pediatric pathology》1997,17(3):427-447
Long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency is a recently discovered disorder affecting the mitochondrial-oxidation of fatty acids. There have been few reports of the pathologic findings in-oxidation defects. We examined pathologic specimens from 16 patients with this disorder (11 patients were homozygous for the common mutation G1528C, 5 patients were siblings with a similar clinical presentation). Autopsies were performed on all 15 patients who died, and liver biopsy specimens were available from 8 patients. Hepatomegaly and steatosis of the liver, found in every patient, were often combined with fibrosis or cirrhosis. Cardiomegaly and accumulation of fat in the myocardium, renal tubules, and skeletal muscle were found in many patients. A detailed neuropathologic examination was performed on six patients, and brain specimens obtained at autopsy were examined in four others. In general, neuropathologic findings were mild and unspecific, but vacuolization was detected in the deep gray matter and in the cerebellum and brain stem nuclei of five patients. In one patient the vacuolization was prominent; in the other four it was milder and more focal. The vacuoles seemed to be either in the neuropil or associated with swollen hydropic cells. The uniform pattern of histopathologic changes facilitates the diagnostics in this severe disorder, allowing opportunities for therapy and prenatal diagnosis. 相似文献
24.
Pekka Venesmaa Clinical Research Fellow Ulf-Håkan Stenman Consultant † Matti Forss Physicist Arto Leminen Consultant Pentti Lehtovirta Consultant Juhani Vartiainen Clinical Research Fellow Jorma Paavonen Associate Professor 《BJOG : an international journal of obstetrics and gynaecology》1998,105(5):508-511
Objective To evaluate the use of the pre-operative tumour-associated trypsin inhibitor (TATI) level and residual tumour size at primary surgery as a prognostic indicators for patients with Stage III epithelial ovarian cancer.
Design Retrospective cohort study.
Setting Department of Obstetrics and Gynaecology, University Hospital, Helsinki, Finland.
Participants Ninety-eight women with Stage III ovarian cancer.
Methods TATI was measured by radioimmunoassay from serum samples obtained within one week before surgery. A cutoff value of 22 μg/L was used. Multivariate analysis included pre-operative TATI level, age, histologic grade and histologic type. Mantel-Cox test was used for calculating statistical significance of differences in survival between groups.
Main outcome measures Cumulative five-year survival, pre-operative serum TATI level and residual tumour size.
Results Surgery was optimal (residual tumour size ≤ 2 cm) in 55 patients and suboptimal (residual tumour size > 2 cm) in 43. Pre-operative TATI level ≤ 22 μg/L predicted better prognosis both in patients with optimal and suboptimal surgery compared with patients with pre-operative TATI level > 22 μ/L. Patients with optimal surgery and a pre-operative TATI > 22 μg/L had a twofold relative risk of death compared with those with a pre-operative TATI ≤ 22 μg/L. The cumulative survival was less than three years for patients with suboptimal surgery and pre-operative TATI > 22 μg/L.
Conclusions Pre-operative serum TATI in combination with residual tumour size may be useful in stratifying patients with Stage III ovarian cancer into different categories in randomised treatment trials. 相似文献
Design Retrospective cohort study.
Setting Department of Obstetrics and Gynaecology, University Hospital, Helsinki, Finland.
Participants Ninety-eight women with Stage III ovarian cancer.
Methods TATI was measured by radioimmunoassay from serum samples obtained within one week before surgery. A cutoff value of 22 μg/L was used. Multivariate analysis included pre-operative TATI level, age, histologic grade and histologic type. Mantel-Cox test was used for calculating statistical significance of differences in survival between groups.
Main outcome measures Cumulative five-year survival, pre-operative serum TATI level and residual tumour size.
Results Surgery was optimal (residual tumour size ≤ 2 cm) in 55 patients and suboptimal (residual tumour size > 2 cm) in 43. Pre-operative TATI level ≤ 22 μg/L predicted better prognosis both in patients with optimal and suboptimal surgery compared with patients with pre-operative TATI level > 22 μ/L. Patients with optimal surgery and a pre-operative TATI > 22 μg/L had a twofold relative risk of death compared with those with a pre-operative TATI ≤ 22 μg/L. The cumulative survival was less than three years for patients with suboptimal surgery and pre-operative TATI > 22 μg/L.
Conclusions Pre-operative serum TATI in combination with residual tumour size may be useful in stratifying patients with Stage III ovarian cancer into different categories in randomised treatment trials. 相似文献
25.
Nina Enberg Juhani Wolf Anja Ainamo Hannu Alho Pekka Heinälä Marianne Lenander-Lumikari 《Acta odontologica Scandinavica》2013,71(6):341-347
A total of 85 Finnish alcohol-dependent subjects and 53 controls were studied with panoramic radiography. The aim was to study the possible associations between prolonged alcohol consumption and dental health. The mean number of teeth, caries lesions, endodontic treatments, periapical lesions, marginal bone loss, and periodontal infrabony pockets was studied. The subjects met the diagnostic criteria of alcohol dependence as set out in DSM-IV and ICD-10. The control group comprised social drinking volunteers with an AUDIT score h 8. For the final results the subjects were divided into groups on the basis of sex and age. The social backgrounds of the subjects were similar, except for employment and smoking. The results show significantly fewer teeth and more caries in the alcoholic group. There was a tendency for the alcoholics <45 years of age to have more endodontically treated teeth than the controls, but no difference in the number of periapical lesions in endodontically treated teeth was found. Horizontal bone loss and the presence of calculus were more frequent in alcoholic men than in alcoholic women. Significantly more horizontal bone loss was observed in the group of alcoholic nonsmokers than in nonalcoholic nonsmokers. In the nonsmoking groups alcoholics had significantly more periodontal destruction than the nonsmoking controls. We conclude that radiological dental health among individuals dependent on alcohol is weakened by more caries, more horizontal bone loss, and more numerous vertical infrabony pockets than social drinkers. 相似文献
26.
27.
The purchaser–provider split (PPS) is a service delivery model in which third-party payers are kept organizationally separate from service providers. The operations of the providers are managed by contracts. One of the main aims of PPS is to create competition between providers. Competition and other incentive structures built into the contractual relationship are believed to lead to improvements in service delivery, such as improved cost containment, greater efficiency, organizational flexibility, better quality and improved responsiveness of services to patient needs. PPS was launched in Finland in the early 1990s but was not widely implemented until the early 2000s. Compared to other countries with PPS the development and implementation of PPS in Finland has been unusual. Firstly, purchasing is implemented at the level of municipalities, which means that the size of the Finnish purchasers is extremely small. Elsewhere purchasing is mostly implemented at the regional or national levels. Secondly, PPS is also applied to primary health care and A&E services while in other countries the services mainly include specialized health care and residential care for the elderly. Thirdly, PPS in health and social services is not regulated by any specific legislation, regulative mechanisms or guidelines. Instead it is regulated within the same framework as public procurement in general. 相似文献
28.
Koskela RM Karttunen TJ Niemelä SE Lehtola JK Ilonen J Karttunen RA 《European journal of gastroenterology & hepatology》2008,20(4):276-282
OBJECTIVES: Coeliac disease (CD) is common in patients with microscopic colitis (MC). The human leucocyte antigen (HLA)-DR3-DQ2 haplotype is strongly associated with CD, and there is evidence for an association with MC. We analysed the genetic background of MC by assessing the haplotypes of HLA-DR3-DQ2 and HLA-DR4-DQ8. In addition, TNFalpha gene polymorphism (-308) associated with susceptibility to several autoimmune diseases was studied. METHODS: Eighty patients with MC including 29 with collagenous colitis (CC) and 51 with lymphocytic colitis (LC) were typed for HLA-DR3-DQ2, and HLA-DR4-DQ8 molecule encoding genes using either an allele-specific PCR, or hybridization with sequence-specific oligonucleotides. Duodenal biopsies (N=78) confirmed the diagnosis of CD in 15 (18.8%) patients. TNFalpha(308) alleles were analyzed in 78 patients with MC (27 with CC and 51 with LC). A control group of 3627 patients was used in the HLA study and 178 patients in the TNFalpha study. RESULTS: HLA-DR3-DQ2 haplotype was more frequent in patients with MC (43.8%) including both subgroups (LC, 44.8%; CC, 43.1%; P<0.001), and MC with CD (86.7%; P<0.001) and without CD (33.3%; P=0.003), compared with the controls (18.1%). Similarly, the TNF2 carrier rate was higher in MC (46.2%; P<0.001) including both CC (44.4%; P=0.031) and LC (47.1%; P=0.001), and both MC patients with CD (66.7%; P=0.001) and without CD (39.3%; P=0.019), compared with the controls (23%). CONCLUSION: Both CC and LC are associated with the HLA-DR3-DQ2 haplotype and with TNF2 allele carriage. These associations are present also in MC patients without CD. The shared predisposing HLA-DR3-DQ2 haplotype and the high prevalence of CD in patients with MC suggest an epidemiological overlap, and probably some similarities in the pathogenesis of CD and MC. 相似文献
29.
Hookana E Junttila MJ Särkioja T Sormunen R Niemelä M Raatikainen MJ Uusimaa P Lizotte E Peuhkurinen K Brugada R Huikuri HV 《Journal of cardiovascular electrophysiology》2008,19(7):743-747
Introduction: We screened the candidate genes from a Finnish family in which the mother was resuscitated from ventricular fibrillation and the daughter died suddenly without any prior cardiac symptoms.
Methods and Results: In addition to screening of potential structural gene mutations, phenotyping of the proband and medico-legal autopsy of the victim of the sudden death, including histopathological examinations, were performed. Genetic screening revealed an R541C mutation in the lamin A/C gene both in the proband and her daughter. None of the 16 first- or second-degree relatives, or 96 unrelated healthy subjects, carried the same mutation. In the proband, the size and the global function of the left ventricle (LV) were normal, but a local hypokinesia and thinning of inferoposterior area of the LV were seen in 2D echocardiography and magnetic resonance imaging. Coronary angiogram and the results of the electrophysiological study were normal. Autopsy of the victim of sudden death showed localized thinning and fibrosis in the inferoposterior area of the LV, with only minimal fibrosis in the right ventricle and no abnormalities in the interventricular septum.
Conclusion: These observations indicate that a fatal or near-fatal cardiac arrhythmia can be the first clinical manifestation of a "de novo" mutation R541C of the lamin A/C gene. Replacement of cardiac myocytes by fibrosis seems to be the predominant pathologic-anatomic finding. 相似文献
Methods and Results: In addition to screening of potential structural gene mutations, phenotyping of the proband and medico-legal autopsy of the victim of the sudden death, including histopathological examinations, were performed. Genetic screening revealed an R541C mutation in the lamin A/C gene both in the proband and her daughter. None of the 16 first- or second-degree relatives, or 96 unrelated healthy subjects, carried the same mutation. In the proband, the size and the global function of the left ventricle (LV) were normal, but a local hypokinesia and thinning of inferoposterior area of the LV were seen in 2D echocardiography and magnetic resonance imaging. Coronary angiogram and the results of the electrophysiological study were normal. Autopsy of the victim of sudden death showed localized thinning and fibrosis in the inferoposterior area of the LV, with only minimal fibrosis in the right ventricle and no abnormalities in the interventricular septum.
Conclusion: These observations indicate that a fatal or near-fatal cardiac arrhythmia can be the first clinical manifestation of a "de novo" mutation R541C of the lamin A/C gene. Replacement of cardiac myocytes by fibrosis seems to be the predominant pathologic-anatomic finding. 相似文献
30.
Päivä H Laakso J Laine H Laaksonen R Knuuti J Raitakari OT 《Journal of the American College of Cardiology》2002,40(7):1241-1247
OBJECTIVE: The goal of this study was to examine the relationship between plasma asymmetric dimethylarginine (ADMA) level and hyperemic myocardial blood flow (MBF) in subjects with borderline hypertension (BHT) and familial hypercholesterolemia (FH). METHODS: Asymmetric dimethylarginine is an endogenous competitive inhibitor of nitric oxide synthase that may modulate vascular function.We measured plasma ADMA levels and myocardial flow in 77 young men (mean age 35 +/- 5 years), including 47 healthy controls, 16 men with BHT, and 14 men with FH. Basal and dipyridamole-induced myocardial flow was measured using positron emission tomography. Plasma ADMA levels were measured using high-pressure liquid chromatography. RESULTS: Asymmetric dimethylarginine levels were significantly elevated in the BHT group compared with controls (0.59 +/- 0.13 micromol/l vs. 0.43 +/- 0.12 micromol/l, p < 0.001), and they had significantly lower dipyridamole flow (2.85 +/- 1.20 ml/min/g vs. 3.69 +/- 1.68 ml/min/g, p < 0.05). In a multivariate regression model adjusted for the study group, dipyridamole flow was inversely associated with ADMA (p < 0.05), age (p < 0.05), and apolipoprotein B concentration (p < 0.05). CONCLUSIONS: We conclude that plasma ADMA concentration is related to dipyridamole-induced vasodilatory function in young men, independently of blood pressure elevation and hypercholesterolemia. Subjects with BHT have significantly increased plasma ADMA levels, which may partly explain the impaired hyperemic MBF in this condition. 相似文献