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Background  

The mitogen-activated protein kinases, MAPKs for short, constitute cascades of signalling pathways involved in the regulation of several cellular processes that include cell proliferation, differentiation and motility. They also intervene in neurological processes like fear conditioning and memory. Since little remains known about the MAPK-Activated Protein Kinase, MAPKAPK5, we constructed the first MAPKAPK knockin mouse model, using a constitutive active variant of MAPKAPK5 and analyzed the resulting mice for changes in anxiety-related behaviour.  相似文献   
5.
One hundred fourteen patients scheduled to undergo elective cholecystectomy were prospectively randomized into one of four treatment groups to study the potential benefits of esophagogastric decompression with and without immediate postoperative enteral nutrition. Group I was the control, and patients received only iv fluids and were allowed to eat as tolerated. Group II patients received iv fluids and esophagogastric decompression. Group III patients received esophagogastric decompression and enteral sterile water through the duodenal feeding lumen. Group IV patients received esophagogastric decompression and infusion of an elemental diet through the feeding lumen. The surgical techniques were standardized for all patients. The results of the study indicated no statistically or clinically significant differences among any of the treatment groups regarding; (1) need for parenteral analgesics or antiemetics, (2) tolerance of regular diet, (3) postoperative day of discharge, and (4) postoperative day that other discharge criteria were met. It is concluded that there is no objective benefit to the routine use of esophagogastric decompression with or without enteral nutrition in elective cholecystectomy patients.  相似文献   
6.
BACKGROUND: High-dose chemotherapy followed by autologous blood stem cell transplantation induces remission of plasma cell dyscrasia in patients with AL amyloidosis. The impact of this treatment on the glomerular amyloid mass is still unknown. METHODS: In the present study, the quantity of the renal amyloid mass before and more than 3 years after high-dose melphalan treatment and autologous blood stem cell transplantation was assessed in two patients. At the time of the second renal biopsy, both patients were in complete remission without detectable serum and urinary monoclonal IgA-lambda and a normal percentage of plasma cells in the bone marrow. RESULTS: In both patients with biopsy-proven AL amyloidosis, urinary protein excretion decreased from 7 g/24 h to <2 g/24 h more than 3 years after autologous blood stem cell transplantation. In contrast, glomerular amyloid deposits persisted, as shown in the second biopsy. CONCLUSION: Despite complete remission of the plasma cell dyscrasia and improvement of glomerular permeability, the amount of glomerular amyloid mass did not regress.  相似文献   
7.
This study was designed to determine the functional characteristics of the endothelium, smooth muscle and nerve terminals of cryopreserved veins. Freshly harvested and cryopreserved canine saphenous veins were cut into rings. In some rings, the endothelium was removed. Cryopreserved veins were stored at -196 degrees C for at least 3 weeks prior to use. All rings contracted in a concentration-dependent manner to depolarization with KCl and to alpha-adrenergic stimulation; the maximal tensions were significantly less in cryopreserved than in freshly harvested veins. Calcium ionophore A23187 caused greater relaxations in rings with than without endothelium in freshly harvested and cryopreserved veins. These relaxations were reduced significantly by methylene blue and NG-monomethyl-L-arginine (L-NMMA) only in fresh veins. Cocaine-sensitive uptake of H3-norepinephrine was reduced following cryopreservation. Immediately after cryopreservation, the production of prostacyclin was elevated. The calcium ionophore A23187 stimulated production of prostacyclin only in freshly harvested veins. Tissue content of endothelin did not change following cryopreservation. These results suggest that cryopreservation of canine saphenous veins alters nerve terminals and decreases the ability of the smooth muscle to contract. The endothelium releases an endothelium-derived relaxing factor and prostanoids following cryopreservation but the ability to synthesize nitric oxide is probably reduced. These changes following cryopreservation may affect patency of the veins when used as arterial grafts.  相似文献   
8.

Aim  

The aim of the present study was to collect and compare cases of drug-induced PML in order to contribute to the debate about the role of the underlying diseases and/or drug immunosuppression in PML occurrence.  相似文献   
9.
Technetium-99m methoxyisobutylisonitrile (MIBI), like thallium-201, has recently been introduced as a myocardial perfusion agent and is now also showing very promising results in parathyroid scintigrapy. The results of 201Tl/99mTc-pertechnetate and 99mTc-MIBI/99mTc-pertechnetate subtraction scintigraphy, ultrasonography and computed tomography are presented in a series of 43 patients operated on for hyperparathyroidism. All four imaging modalities were confirmed to be reliable, scintigraphy being the most accurate. Sensitivities ranged from 81% to 95%, that of 99mTc-MIBI being the highest. Moreover this tracer, which has more favourable physical and also biochemical properties, yielded images of superior quality. This allowed localization of the lesion by visual inspection only in as many as 86% of the patients with positive 99mTc-MIBI/99mTc-pertechnetate subtraction scintigraphy. We believe that the higher sensitivity, superior image quality and lower cost of 99mTc-MIBI imaging will make 99mTc-MIBI the new radiopharmaceutical of choice for parathyroid scintigraphy (when one takes into account the stability of labelling with large activities it is possible to perform three or four cardiac studies together with one parathyroid scintigraphic examination using one lyophililzed vial).  相似文献   
10.
Using a sensitive flow cytometric assay, which measures the intracellular oxidation of 2'7' dichlorofluorescein (DCFH) by H2O2, we have assessed, at a single-cell level, the effects of a variety of physiological priming agonists and cytochalasin B (CB) on purified populations of neutrophils stimulated at different points along the signal response transduction pathway. Pretreatment of purified neutrophils with the physiological priming agonists monocyte interleukin-8 (IL-8), granulocyte-monocyte colony-stimulating factor (GM-CSF), platelet-activating factor (PAF), IL-1 beta, tumour necrosis factor-alpha (TNF-alpha), IL-6, and non-stimulatory doses of formyl-methionyl-leucyl-phenylalanine (FMLP), resulted in an increased percentage of cells generating an oxidative burst in response to subsequent receptor stimulation with FMLP. CB had a similar but much more pronounced effect on cellular recruitment to a receptor-mediated responsive state. Activation of protein kinase C (PKC) using the phorbol ester phorbol myristate acetate (PMA) resulted in a heterogeneous response, with all cells generating H2O2, but with two populations differing in their magnitude of response. Physiological priming agonists had no effect on the heterogeneity of the PMA response. However, pretreatment with CB dramatically altered the PMA response, producing a homogeneous population highly responsive to stimulation with PKC. In contrast, direct stimulation of G proteins with fluoride (A1F-4) was primed both by physiological priming agonists and by CB. These results demonstrate that priming of neutrophils by physiological agonists involves changes at the level of signal transduction which enable a previously non-responsive cell to respond to a secondary stimulus.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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