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61.
62.
During hypoxic exercise some vasoconstriction is needed to match O2 delivery with O2 demand at the microcirculatory level. 总被引:1,自引:0,他引:1
Carsten Lundby Robert Boushel Paul Robach Kirsten M?ller Bengt Saltin José A L Calbet 《The Journal of physiology》2008,586(1):123-130
To test the hypothesis that the increased sympathetic tonus elicited by chronic hypoxia is needed to match O(2) delivery with O(2) demand at the microvascular level eight male subjects were investigated at 4559 m altitude during maximal exercise with and without infusion of ATP (80 mug (kg body mass)(-1) min(-1)) into the right femoral artery. Compared to sea level peak leg vascular conductance was reduced by 39% at altitude. However, the infusion of ATP at altitude did not alter femoral vein blood flow (7.6 +/- 1.0 versus 7.9 +/- 1.0 l min(-1)) and femoral arterial oxygen delivery (1.2 +/- 0.2 versus 1.3 +/- 0.2 l min(-1); control and ATP, respectively). Despite the fact that with ATP mean arterial blood pressure decreased (106.9 +/- 14.2 versus 83.3 +/- 16.0 mmHg, P < 0.05), peak cardiac output remained unchanged. Arterial oxygen extraction fraction was reduced from 85.9 +/- 5.3 to 72.0 +/- 10.2% (P < 0.05), and the corresponding venous O(2) content was increased from 25.5 +/- 10.0 to 46.3 +/- 18.5 ml l(-1) (control and ATP, respectively, P < 0.05). With ATP, leg arterial-venous O(2) difference was decreased (P < 0.05) from 139.3 +/- 9.0 to 116.9 +/- 8.4(-1) and leg .VO(2max) was 20% lower compared to the control trial (1.1 +/- 0.2 versus 0.9 +/- 0.1 l min(-1)) (P = 0.069). In summary, at altitude, some degree of vasoconstriction is needed to match O(2) delivery with O(2) demand. Peak cardiac output at altitude is not limited by excessive mean arterial pressure. Exercising leg .VO(2peak) is not limited by restricted vasodilatation in the altitude-acclimatized human. 相似文献
63.
The influence of HLA-A, B-matching on the results of 362 cadaver renal transplantations was analyzed. Of these, 34 of the patients had diabetes and 105 were 55 years old or more. The case material was divided into groups, based on the number of HLA-A, B incompatibilities. The occurence of factors having a possible bearing on kidney graft survival was determined in each match group. It was found that several of these factors, such as the immunosuppressive agents given and the number of high-risk patients, were unequally distributed in the various groups. This may be related to changes in policy that have occured since the transplant unit was moved to Huddinge Hospital in November 1973. In order to obtain homogeneous case material, the Huddinge series was analyzed separately.
A significant difference in survival was found in both materials between transplants with 2 or less incompatibilities and those with more than 2 incompatibilities. A significant difference in patient survival between these two groups was found in the total case material. 相似文献
A significant difference in survival was found in both materials between transplants with 2 or less incompatibilities and those with more than 2 incompatibilities. A significant difference in patient survival between these two groups was found in the total case material. 相似文献
64.
Two test-kits — API and Oxi Ferm tube — have been compared for accuracy in individual tests and for identification on the genus or species level with conventional biochemical tests on 154 oxidative-fermentative gram-negative rods. The two test systems were found to be reliable and permit identification of the clinically most significant oxidative-fermentative strains. 相似文献
65.
Anders Pettersson Kathryn Gradin Thomas Hedner Bengt Persson 《Naunyn-Schmiedeberg's archives of pharmacology》1985,329(4):394-397
Summary Ketanserin is a new antihypertensive agent with affinity to serotonin (5-HT)2 receptors and at higher concentrations also to
1-adrenoceptors. The present study was designed to evaluate the relative functional importance of the antagonism of
1-adrenoreceptors and 5-HT2-receptors in the antihypertensive mechanism of action of ketanserin and analogues after acute administration. In the spontaneously hypertensive rat, ketanserin and the two ketanserin analogues, R56413 and R55667 (which have relatively weaker -adrenolytic properties) were studied with regard to their ability to reduce the blood pressure after acute administration in the conscious rat and their ability to shift the dose response curves for 5-HT and phenylephrine in the pithed rat. The agents tested reduced the blood pressure only in a dose range where they blocked
1-adrenoceptors and there was a striking correlation between the degree of hypotension and the degree of inhibition of the phenylephrine induced pressor responses. 5-HT2-receptor blockade alone did not influence basal blood pressure. However, following pretreatment with R55667 in a low dose the blood pressure reduction to prazosin was enhanced.It is concluded that following acute administration in the rat the major portion of the antihypertensive response to ketanserin is due to an
1-adrenoceptor blockade but that the 5-HT2-receptor blockade contributes.Abbreviations 5-HT
5-hydroxytryptamine
- SHR
spontaneously hypertensive rat
- SNS
sympathetic nervous stimulation 相似文献
66.
Bengt R. G. Danielsson 《Archives of toxicology》1984,55(3):161-167
The distribution in pregnant C57BL mice (day 18 of gestation) of intravenously administered cadmium (Cd) chloride and mercury (Hg) chloride (0.75 mol/kg b.w.) was studied, with or without previous dithiocarbamate pretreatment. Diethyldithiocarbamate (DEDTC), disulfiram, or thiram (2×1 mmol/kg b.w.) or vehicle (gelatine) alone, were given by gavage 2 h before and immediately after injection of the metals. The mice were sacrificed 4 and 24 h later and subjected to autoradiography or impulse counting of excised organs.All the dithiocarbamates increased the concentration of both Cd and Hg in brain and most other maternal organs. While DEDTC and thiram, in that order, strongly increased Cd concentrations in whole fetuses (around 17-fold at 4 h) and all fetal organs measured, disulfiram caused a decrease in fetal Cd concentrations. For Hg, all the dithiocarbamates substantially decreased fetal levels. Disulfiram, for example, decreased Hg levels by a factor of 5. The 24 h values confirmed those at 4 h both elements, although the differences between control and treatment groups were less pronounced.Although the results suggest the formation of lipid-soluble metal-dithiocarbamate complexes in vivo (e.g., increased concentration in brain), this does not necessarily lead to increased fetal levels of the metals. The increased levels of Cd after thiram and DEDTC pretreatment, however, indicate a risk for higher Cd fetotoxicity. It is likely that Cd is released in fetal cells following metabolism of the dithiocarbamate moiety of the complex. 相似文献
67.
Lindgren Peter Lfvendahl Sofia Brdvik Gunnar Weiland Ola Jnsson Bengt 《The European journal of health economics》2022,23(6):1059-1070
The European Journal of Health Economics - In 2015, the Swedish government in an unprecedented move decided to allocate 150 million € to provide funding for new drugs for hepatitis C. This... 相似文献
68.
Marcus Bergström Ming Yao Malin Müller Olle Korsgren Bengt von Zur-Mühlen Torbjörn Lundgren 《Transplant international》2021,34(12):2816-2823
Allogeneic islet transplantation in type 1 diabetes requires lifelong immunosuppression to prevent graft rejection. This medication can cause adverse effects and increases the susceptibility for infections and malignancies. Adoptive therapies with regulatory T cells (Tregs) have shown promise in reducing the need for immunosuppression in human transplantation settings but have previously not been evaluated in islet transplantation. In this study, five patients with type 1 diabetes undergoing intraportal allogeneic islet transplantation were co-infused with polyclonal autologous Tregs under a standard immunosuppressive regimen. Patients underwent leaukapheresis from which Tregs were purified by magnetic-activated cell sorting (MACS) and cryopreserved until transplantation. Dose ranges of 0.14–1.27 × 106 T cells per kilo bodyweight were transplanted. No negative effects were seen related to the Treg infusion, regardless of cell dose. Only minor complications related to the immunosuppressive drugs were reported. This first-in-man study of autologous Treg infusion in allogenic pancreatic islet transplantation shows that the treatment is safe and feasible. Based on these results, future efficacy studies will be developed under the label of advanced therapeutic medical products (ATMP), using modified or expanded Tregs with the aim of minimizing the need for chronic immunosuppressive medication in islet transplantation. 相似文献
69.
John M. Søfteland Gustav Friman Bengt von Zur-Mühlen Bo-Göran Ericzon Carin Wallquist Kristjan Karason Vanda Friman Jan Ekelund Marie Felldin Jesper Magnusson Ida Haugen Löfman Andreas Schult Emily de Coursey Susannah Leach Hanna Jacobsson Jan-Åke Liljeqvist Ali R. Biglarnia Per Lindnér Mihai Oltean 《American journal of transplantation》2021,21(8):2762-2773
Solid organ transplant (SOT) recipients run a high risk for adverse outcomes from COVID-19, with reported mortality around 19%. We retrospectively reviewed all known Swedish SOT recipients with RT-PCR confirmed COVID-19 between March 1 and November 20, 2020 and analyzed patient characteristics, management, and outcome. We identified 230 patients with a median age of 54.0 years (13.2), who were predominantly male (64%). Most patients were hospitalized (64%), but 36% remained outpatients. Age >50 and male sex were among predictors of transition from outpatient to inpatient status. National early warning Score 2 (NEWS2) at presentation was higher in non-survivors. Thirty-day all-cause mortality was 9.6% (15.0% for inpatients), increased with age and BMI, and was higher in men. Renal function decreased during COVID-19 but recovered in most patients. SARS-CoV-2 antibodies were identified in 78% of patients at 1–2 months post-infection. Nucleocapsid-specific antibodies decreased to 38% after 6–7 months, while spike-specific antibody responses were more durable. Seroprevalence in 559 asymptomatic patients was 1.4%. Many patients can be managed on an outpatient basis aided by risk stratification with age, sex, and NEWS2 score. Factors associated with adverse outcomes include older age, male sex, greater BMI, and a higher NEWS2 score. 相似文献
70.
T. Friden T. Erlandsson R. Zätterström A. Lindstrand U. Moritz 《Knee surgery, sports traumatology, arthroscopy》1995,3(3):144-147
100 consecutive patients with a recent anterior cruciate ligament injury were examined with respect to type of sports activity that caused the injury, mechanism of injury and the occurrence of collateral ligament and meniscal lesions. There were 53 medial collateral ligament injuries, 12 medial, 35 lateral and 11 bicompartmental meniscal lesions. 59 patients were injured during contact sports, 30 in downhill skiing and 11 in other recreational activities, traffic accidents or at work. An associated medial collateral, ligament tear was more common in skiing (22/30) than during contact sports (23/59), whereas a bicompartmental meniscal lesion was found more frequently in contact sports (9/59) than in skiing (0/30). Weightbearing was reported by 56/59 of the patients with contact sports injuries and by 8/30 of those with skiing injuries. Non-weightbearing in the injury situation led to the same rate of MCL tears (18/28) as those reporting weightbearing (35/72) but significantly more intact menisci (19/28 vs 23/72). Thus, contact sports injuries were more often sustained during weightbearing, with a resultant joint compression of both femuro-tibial compartments as shown by the higher incidence of bicompartmental meniscal lesions. This might be an important prognostic factor for future joint disease and arthrosis. The classic unhappy triad was a rare finding (8/100) and we suggest that this entity should be replaced by the unhappy compression injury. 相似文献