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排序方式: 共有1932条查询结果,搜索用时 15 毫秒
31.
Basophil histamine release and lymphocyte proliferation tests were examined with latex allergen prepared from surgical gloves in 15 patients with latex contact urticaria. The basophil histamine release test (BHRT) yielded positive results in 13/14 (93%) patients, whereas commercial latex RAST was positive in only 9/15 (60%) patients. Lymphocyte proliferation test (LPT) was positive in 3/15 (20%) patients, suggesting that cell-mediated immune reactions may also occur in latex allergy. However, patch tests to latex were negative and neither were epidermal Langerhans cells able to present latex antigen to T lymphocytes in vitro. 相似文献
32.
Arjamaa O Mäkinen T Turunen L Huttunen P Leppäluoto J Vuolteenaho O Rintamäki H 《European journal of applied physiology》2001,84(1-2):48-53
In the study reported here, we examined blood pressure and endocrine responses in cold conditions during salt load in young
healthy subjects who had previously shown increased resting blood pressure during acutely increased sodium intake. Subjects
(n=53) added 121 mmol sodium into their normal diet for 1 week. If their mean arterial pressure had increased by a minimum of
5 mmHg compared to the previous measure they were selected for subsequent experiments. The subjects (n=8) were given 121 mmol supplemental sodium · day−1 for 14 days. They were then put into a wind tunnel for 15 min (temperature −15 °C, wind speed 3.5 · ms−1). Their blood pressure increased (P < 0.05) during the cold exposure, independent of the sodium intake. Their mean (SEM) plasma noradrenaline increased from
3.58 (0.62) nmol · l−1 to 5.61 (0.79) nmol · l−1 (P < 0.05) when the subjects were given a normal diet, and from 2.45 (0.57) nmol · l−1 to 5.06 (0.56) nmol · l−1 (P < 0.05) when the subjects were given an elevated sodium diet. The starting concentrations and the endpoint concentrations
were statistically similar. The plasma levels of the N-terminal fragment of pro-atrial natriuretic peptide decreased during
the whole-body cold exposure: with the sodium load the change was from 256.6 (25.5) nmol · l−1 to 208.0 (25.3) nmol · l−1, and with the normal diet, from 205.8 (16.4) nmol · l−1 to 175.1 (16.1) nmol · l−1. The haematocrit and red blood cell count increased (P < 0.05) with normal and elevated sodium diet in cold conditions, but haemoglobin increased (P < 0.05) only with high salt in cold conditions. To conclude, acutely increased sodium intake does not change the blood pressure
response or hormonal responses to exposure to acute cold stress in healthy subjects.
Accepted: 28 September 2000 相似文献
33.
Juhani Smolander Veikko Louhevaara Timo Tuomi Olli Korhonen Juhani Jaakkola 《International archives of occupational and environmental health》1984,54(3):261-270
Summary Six healthy men aged 25 to 37 walked on a treadmill at work levels of 21 and 41% of their
for 25 to 30 min wearing gas protective clothing (GPC) consisting of an impermeable suit with a self-contained breathing apparatus (total weight 25 kg) or shorts (control tests, CT) in a temperate environment (t
a 24.3°C ± 1.0°C, rh 30–50%). When the GPC was worn at 21 and 41%
, the most prominent increases, compared with the CT, were noted in the heart rate (
± SE, 120 ± 5 vs 76 ± 3 beats min–1 and 171 ± 5 vs 103 ± 3 beats min–1), mean skin temperature (36.1 ± 0.2 vs 31.3° C ± 0.1°C and 36.9 ± 0.3 vs 30.9°C ± 0.4°C) and sweat rate (473 ± 51 vs 70 ± 23 g m–2 h–1 and 766 ± 81 vs 135 ± 18 g m–2 h–1) indicating a high cardiovascular and thermoregulatory strain, which was not decreased by ventilating the suit with an air flow of 281 min–1 at 41%
. The ventilation, oxygen consumption and production of carbon dioxide increased in relation to the extra weight of the GPC, partly dependent on the dynamic work level. It was concluded that the increase in the physiological load caused by the GPC was so high that the work-rest regimens, workers' level of physical fitness, cardiovascular health and heat tolerance should be considered whenever gas protective clothing is used. 相似文献
34.
Steven K. Koester Juhani U. Maenpaa Valerie J. Wiebe W. Jeffrey Baker Gregory T. Wurz Robert C. Seymour R. Ellen Koehler Michael W. DeGregorio 《Breast cancer research and treatment》1994,32(1):57-65
Summary Flow cytometric analysis of DNA ploidy and S-phase fraction are well recognized prognostic indicators in breast cancer. The present paper deals with the widening of the applications of flow cytometry to monitoring the effectiveness of antiestrogen therapy, detecting clonal selection and emergence of drug resistance, and monitoring chemosensitizing properties of drugs. Antiestrogen activity can be studied by DNA flow cytometry to address clinical research problems such as patient-specific pharmacokinetics, dosing compliance, and acquired antiestrogen resistance. Patient plasma specimens containing various concentrations of triphenylethylenes can be monitored for drug-induced effects using cell cycle measurements and correlated toin vivo drug levels. DNA flow cytometry has also been instrumental in the study of the effects of prolonged low-dose (0.5 µM for > 100 days) tamoxifen treatment on human estrogen receptor negative MDA-MB-231 cells, where it was shown that tamoxifen may significantly alter cell cycle kinetics and tumorigenicity of these cells, selecting a new, more aggressive, and rapidly growing clone. Lastly, it has been shown that the chemosensitizing properties of another triphenylethylene antiestrogen, toremifene, on estrogen receptor negative, multidrug resistant MDA-MB-231-A1 human breast cancer cells can be studied using flow cytometric analysis. Toremifene (and its metabolites N-desmethyltoremifene and toremifene IV) are able to resensitize MDA-MB-231-A1 cells to vinblastine and doxorubicin, as reflected in a marked shift of cells to G2/M phase of the cell cycle. Flow cytometry is a widely available technique that might be applied clinically to monitor, at the cellular level, drug effects on tumors, including the modulators of drug resistance. 相似文献
35.
Angelika Bischof Delaloye Liselotte H?jgaard Juhani Knuuti 《European journal of nuclear medicine and molecular imaging》1995,22(12):BP39-BP39
Blue pages
European school of nuclear medicine 3rd seminar 相似文献36.
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
37.
Enhanced film-forming properties for ethyl cellulose and starch acetate using n-alkenyl succinic anhydrides as novel plasticizers 总被引:4,自引:0,他引:4
Maarit Tarvainen Riitta Sutinen Soili Peltonen Hannu Mikkonen Jaana Maunus Kalle Vh-Heikkil Vesa-Pekka Lehto Petteri Paronen 《European journal of pharmaceutical sciences》2003,19(5):363-371
Purpose: The aim of this study was to investigate the ability of n-alkenyl succinic anhydrides (n-ASAs) to improve the film-forming characteristics of a novel coating polymer, potato starch acetate degree of substitution 2.8 (SA). n-ASAs were also applied to improve the otherwise brittle properties of ethyl cellulose (EC) aqueous dispersion (Aquacoat®) and EC solvent-based films. Methods: The effectiveness of two n-ASAs, 2-octenyl succinic anhydride (OSA) and 2-dodecen-1-ylsuccinic anhydride were evaluated as plasticizers. Mechanical properties, both water vapor and drug permeabilities, and glass transition temperatures of the cast free films were measured. Triethyl citrate and dibutyl sebacate were used as reference plasticizers. Results: The long hydrocarbon chain of n-ASA, with its accessible carbonyl groups, enabled a strong plasticization effect on the tested polymers. Due to the excellent mechanical properties (i.e., a tough film structure with considerable flexibility) and low permeability of the plasticized films, n-ASAs, and especially OSA proved to be an ideal plasticizer particularly for EC based coatings. Also, the EC aqueous dispersion plasticized with n-ASAs resulted in a markedly enhanced coalescence of the colloidal polymer particles, even at low drying temperatures. Conclusions: In applications where a coating with high flexibility is required, n-ASAs can be used as plasticizers at moderately high concentrations (up to 60–70%, w/w) without losing the high tensile strength, excellent toughness and low permeability of EC and SA films. 相似文献
38.
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
39.
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
40.
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