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排序方式: 共有306条查询结果,搜索用时 15 毫秒
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Ambuhl P; Wuthrich R; Korte W; Schmid L; Krapf R 《Nephrology, dialysis, transplantation》1997,12(11):2355-2364
Background: Thrombotic complications are common in
patients with endstage renal disease and contribute substantially to the
morbidity and mortality in this population. The aim of the present study
was to: I) determine the prevalence and the extent of hypercoagulability in
patients undergoing dialysis treatment by measuring parameters that
directly reflect thrombin concentrations, ii) assess changes in coagulation
status during haemodialysis (HD); iii) quantify the relative impact of
heparin, dialysis and their combined effects on coagulation status and iv)
detect factors that modify coagulation haemostasis in dialysis patients.
Method: A total of 39 patients (HD: n=29, CAPD: n=10)
was analysed for procoagulatory and fibrinolytic activity determined by
measurements of partial thromboplastin time, prothrombin fragments F1+2,
thrombin-antithrombin complexes and D-dimer concentrations. HD patients
were investigated prior to and during dialysis. A subgroup of patients was
infused heparin alone without dialysis or was dialysed without heparin
administration. Furthermore, subgroup and correlation analyses were
performed for the type of dialysis (HD vs CAPD), dialyzer and shunt, Kt/V,
underlying disease and treatment with recombinant erythropoietin (rhEPO).
Results: Baseline levels of all
parameters-procoagulatory and fibrinolytic- were substantially elevated in
all patients, but to a higher degree among those on CAPD. Moreover,
haemodialysis treatment increased procoagulatory markers even further,
suggesting stimulated coagulation and/or insufficient anticoagulation
during dialysis. However, after 3 h of dialysis thrombin concentrations,
determined by quantification of prothrombin fragments, were inversely
correlated with Kt/V. Selective heparin infusion diminished procoagulatory
activity only slightly and incompletely, whereas HD without heparin
resulted in excess thrombin accumulation. Finally, subgroup analyses
revealed more pronounced thrombin formation among patients treated with
polysulfon dialyzers, whereas erythropoietin dosage was positively related
with lower procoagulatory activity. Conclusion: A
majority of patients on dialysis are in a hypercoagulable state, which is
further aggravated by the haemodialysis procedure itself and may not be
sufficiently controlled with current anticoagulation regimens. Intensified
heparin treatment and the use of rhEPO are likely to improve coagulation
haemostasis, whereas the type of dialyzer should be considered as a
relevant procoagulatory factor. 相似文献
3.
Andreas W. Jehle Judith Forgo J. Biber Eleanor Lederer Reto Krapf Heini Murer 《Pflügers Archiv : European journal of physiology》1998,437(1):149-154
Insulin-like growth factor (IGF)-I and vanadate increase Na-dependent phosphate (Na/Pi) cotransport in opossum kidney (OK) cells. To gain more information about the mechanisms by which IGF-I and vanadate stimulate
Na/Pi-cotransport, we measured type II Na/Pi-cotransporter (NaPi-4) protein abundance by Western blot analysis and investigated the effects of protein synthesis and tyrosine
kinase inhibitors. The key findings in the present studies are as follows. First, incubation in IGF-I (10–8 M) and/or vanadate (10–3 M) for 3 h led to a non-additive 1.4-fold increase in Na/Pi-cotransport activity which was paralleled by a 1.5- to 2-fold increase in NaPi-4 protein. Second, actinomycin D did not abolish
the increase in Na/Pi-cotransport and cycloheximide did not prevent the IGF-I-induced increase in Na/Pi-cotransport and NaPi-4 protein. Third, among the protein kinase inhibitors tested, only staurosporine substantially reduced
the stimulation of Na/Pi-cotransport. In conclusion, the stimulatory effect of IGF-I on Na/Pi-cotransport is paralleled by an increased expression of NaPi-4 protein that is independent of protein synthesis and therefore
results from increased protein stability. The observation that IGF-I and/or vanadate lead to similar increases in Na/Pi-cotransport and NaPi-4 protein abundance provides further evidence that the stimulation of Na/Pi-cotransport by IGF-I and vanadate involves protein tyrosine phosphorylation of the same signalling molecules.
Received: 1 May 1998 / Received after revision: 25 August 1998 / Accepted: 1 September 1998 相似文献
4.
Weber WA Neverve J Sklarek J Ziegler SI Bartenstein P King B Treumann T Enterrottacher A Krapf M Häussinger KE Lichte H Präuer HW Thetter O Schwaiger M 《European journal of nuclear medicine》1999,26(4):388-395
Dual-head gamma cameras operated in coincidence mode are a new approach for tumour imaging using fluorine-18 fluorodeoxyglucose (FDG). The aim of this study was to assess the diagnostic accuracy of such a camera system in comparison with a full-ring positron emission tomography (PET) system in patients with lung cancer. Twenty-seven patients (1 female, 26 males, age 62+/-9 years) with lung cancer or indeterminate pulmonary nodules were studied on the same day with a full-ring PET scanner (Siemens ECAT EXACT) and a coincidence gamma camera system (ADAC Vertex MCD). Sixty minutes after injection of 185-370 MBq FDG, a scan of the chest was performed with the full-ring system. Approximately 2 h p.i., the coincidence camera study was performed. Coincidence gamma camera (CGC) and PET images with (PETac) and without attenuation correction (PETnac) were analysed independently by two blinded observers. In addition, FDG uptake in primary tumours and involved lymph nodes was quantified relative to normal contralateral lung (T/L ratios). All primary tumours were histologically proven. The lymph node status was histologically determined in 23 patients. In four patients, no lymph node sampling was performed because of extensive disease or concurrent illnesses. In the 27 patients, 25 primary lung cancers and two metastatic lesions were histologically diagnosed. The number of coincidences per centimetre axial field of view was 3.33+/-0. 93x10(5) for the CGC and 1.09+/-0.36x10(6) for the dedicated PET system. All primary tumours (size: 4.6+/-2.6 cm) were correctly identified in the CGC and dedicated PET studies. T/L ratios were 4. 7+/-2.5 for CGC and 6.9+/-2.8 for PETnac (P <0.001). Histopathological evaluation revealed lymph node metastases in 11 of 88 sampled lymph node stations (size: 2.3+/-1.0 cm). All lymph node metastases were identified in the PETac studies, while PETnac detected 10/11 and CGC 8/11. For positive lymph nodes that were visible in CGC and PETnac studies, T/L ratios were 3.7+/-2.3 for CGC and 6.6+/-3.1 for PETnac (P=0.02). The diameters of false-negative lymph nodes in the CGC studies were 0.75, 1.5 and 2 cm. False-positive FDG uptake in lymph nodes was found in two patients with all three imaging methods. For all lesions combined, T/L ratios in CGC relative to PETnac studies decreased significantly with decreasing lesion size (r=0.62; P<0.001). In conclusion, compared with a full-ring PET system the sensitivity of CGC imaging for detection of lung cancer is limited by a lower image contrast which deteriorates with decreasing lesion size. Nevertheless, the ability of CGC imaging to detect pulmonary lesions with a diameter of at least 2 cm appears to be similar to that of a full-ring system. Both systems provide a similar specificity for the evaluation of lymph node involvement. 相似文献
5.
CL Sanchez CS Biskup S Herpertz TJ Gaber CM Kuhn SH Hood FD Zepf 《The international journal of neuropsychopharmacology / official scientific journal of the Collegium Internationale Neuropsychopharmacologicum (CINP)》2015,18(10)
The neurotransmitters serotonin and dopamine both have a critical role in the underlying neurobiology of different behaviors. With focus on the interplay between dopamine and serotonin, it has been proposed that dopamine biases behavior towards habitual responding, and with serotonin offsetting this phenomenon and directing the balance toward more flexible, goal-directed responding. The present focus paper stands in close relationship to the publication by Worbe et al. (2015), which deals with the effects of acute tryptophan depletion, a neurodietary physiological method to decrease central nervous serotonin synthesis in humans for a short period of time, on the balance between hypothetical goal-directed and habitual systems. In that research, acute tryptophan depletion challenge administration and a following short-term reduction in central nervous serotonin synthesis were associated with a shift of behavioral performance towards habitual responding, providing further evidence that central nervous serotonin function modulates the balance between goal-directed and stimulus-response habitual systems of behavioral control. In the present focus paper, we discuss the findings by Worbe and colleagues in light of animal experiments as well as clinical implications and discuss potential future avenues for related research. 相似文献
6.
ST Hornby FD McDermott M Coleman Z Ahmed J Bunni D Bunting M Elshaer V Evans A Kimble M Kostalas G Page J Singh L Szczebiot S Wienand-Barnett A Wilkins O Williams P Newell Severn Peninsula Audit Research Collaborative 《Annals of the Royal College of Surgeons of England》2015,97(2):115-119
Background
Laparoscopic hernia repair is used widely for the repair of incisional hernias. Few case studies have focussed on purely ‘incisional’ hernias. This multicentre series represents a collaborative effort and employed statistical analyses to provide insight into the factors predisposing to recurrence of incisional hernia after laparoscopic repair. A specific hypothesis (ie, laterality of hernias as well as proximity to the xyphoid process and pubic symphysis predisposes to recurrence) was also tested.Methods
This was a retrospective study of all laparoscopic incisional hernias undertaken in six centres from 1 January 2004 to 31 December 2010. It comprised a comprehensive review of case notes and a follow-up using a structured telephone questionnaire. Patient demographics, previous medical/surgical history, surgical procedure, postoperative recovery, and perceived effect on quality of life were recorded. Repairs undertaken for primary ventral hernias were excluded. A logistic regression analysis was then fitted with recurrence as the primary outcome.Results
A total of 186 cases (91 females) were identified. Median follow-up was 42 months. Telephone interviews were answered by 115/186 (62%) of subjects. Logistic regression analyses suggested that only female sex (odds ratio (OR) 3.53; 95% confidence interval (CI) 1.39–8.97) and diabetes mellitus (3.54; 1–12.56) significantly increased the risk of recurrence. Position of the defect had no statistical effect.Conclusions
These data suggest an increased risk of recurrence after laparoscopic incisional hernia repair in females and subjects with diabetes mellitus. These data will help inform surgeons and patients when considering laparoscopic management of incisional hernias. We recommend a centrally hosted, prospectively maintained national/international database to carry out additional research. 相似文献7.
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