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1.
Oxidative stress, defined as an imbalance between the production of reactive oxygen species (ROS) and antioxidant defense, is considered to be an important pathogenic factor in diabetes mellitus and its complications. In diabetic state, ROS might also be implicated in promoting a state of systemic inflammation. Recently, it was demonstrated that antioxidant therapy could be used to stop the initiation and propagation of this inflammatory response. Repaglinide is a new oral antidiabetic agent with a possible antioxidant activity. Therefore, in the present study, a possible therapeutic value of repaglinide in ameliorating the oxidative and inflammatory processes was tested in diabetic animals. In the study, the levels of total antioxidant status (TAS), ascorbic acid (AA), protein carbonyl groups (PCG) and interleukin-6 (IL-6) were determined in plasma of diabetic rabbits after 4 and 8 weeks of repaglinide treatment (1mg daily). Ex vivo analysis revealed that there were significant differences in these markers between hyperglycemic and control animals (P<0.05). Some of these parameters were ameliorated by repaglinide treatment. In diabetic rabbits treated with repaglinide, protein oxidation was diminished by 17.8% after 8 weeks of experiment. The level of AA in plasma of diabetic treated animals was higher than in non-treated diabetic groups (by 9.4 and 22.6% after 4 and 8 weeks, respectively). In diabetic treated animals, the TAS level was also significantly increased (by 23.6 and 16.7%). However, in diabetic rabbits, repaglinide did not affect the concentration of IL-6.  相似文献   
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Violence at the workplace--a questionnaire survey of nurses.   总被引:2,自引:0,他引:2  
BACKGROUND: In the health sector, anywhere in the world nurses are one of the most exposed groups to violence. However, it is not obvious that psychiatric nurses (PNs) are more exposed to aggression and burnout. OBJECTIVES: To determine the nature and effects of aggressive acts towards nursing staff in psychiatric and other medical services in Poland. METHODS: Various questionnaires (Stress at Work Scale, General Health Questionnaire, Maslach Burnout Inventory, Work Satisfaction Scale), were distributed among psychiatric (N=78) and non-psychiatric nurses (N-PNs) (N=335). A 92.6% response rate was achieved. RESULTS: Significant differences were found between PNs and non-psychiatric counterparts with respect to their experiences of violence. The most frequently reported incident was verbal abuse, followed by threats and physical assault. Patients were significantly more frequent perpetrators in psychiatric wards than in others. The level of intra-staff aggression did not significantly vary between groups, neither did the level of work satisfaction and absenteeism. CONCLUSION: The frequency of violent acts and stress related to them point out the strong need for the development of preventive programs to address the issue of violence at work.  相似文献   
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BACKGROUND: Systemic sclerosis (SSc) is a connective tissue disorder of unknown etiology characterized by fibrosis of the skin and visceral organs, in which the heart is frequently (40-70% of patients) and severely involved. Pulmonary hypertension affects 10-15% of patients with SSc and is one of the most important complications adversely influencing their survival. CASE REPORT: The case report presents a 59-year-old male patient with advanced systemic sclerosis whose initial examination revealed pulmonary hypertension, rhythm and atrioventricular conduction disturbances, and elevated level of NT-proBNP. After six months the patient deteriorated; an increase in NT-proBNP level and progression of pulmonary hypertension were observed. CONCLUSIONS: The described case is followed by a discussion of cardiovascular involvement in systemic sclerosis and emphasizes that heart involvement in SSc may have very serious clinical implications.  相似文献   
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The purpose of this study was (a) evaluation of dynamic contrast-enhanced MR imaging of normal bone marrow versus malignant bone marrow infiltrations in patients with proven B-cell-type chronic lymphocytic leukemia (B-CLL) and (b) correlation with the clinical stage according to Binet (stages A, B, C) and response to therapy. Bone marrow imaging of the lumbar spine, pelvis, and proximal femurs was performed at 1.5 T in 45 patients without known malignancy and in 30 patients with B-CLL. The differences between opposed-phase and in-phase dynamic gradient-echo sequences before and up to 10 minutes after intravenous application of .1 mmol/kg body weight of gadolinium-diethylenetriamine penta-acetic acid (Gd-DTPA) were evaluated in normal bone marrow. The contrast-enhancement patterns of normal and malignant bone marrow were compared using the opposed-phase dynamic gradient-echo sequence. Ten of the patients with bone marrow infiltrations (Binet stage C) additionally underwent MR imaging follow-up during therapy. Opposed-phase gradient echo sequences demonstrated a signal decrease of normal bone marrow, and in-phase gradient echo sequences demonstrated a signal increase of normal bone marrow after administration of Gd-DTPA. The dynamic signal intensity time courses differed significantly (P < .05) between Binet stages B and C and controls as well as among the three Binet stages of B-CLL. In the 10 patients followed during therapy, MR imaging sensitively demonstrated response (n = 6), nonresponse (n = 2), or relapse after initial response (n = 2). In out-of-phase imaging, both normal bone marrow and initial bone marrow infiltration in CLL stage Binet A show signal decrease after administration of contrast agent, whereas there is increase in signal intensity in higher-grade bone marrow infiltration in Binet stage B or C disease. The signal loss of normal bone marrow in out-of-phase imaging is a phase effect rather than a T2* effect. The differentiation of initial from higher-grade bone marrow infiltration on out-of-phase images relies solely on a shift in the fat/water ratio.  相似文献   
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Benfluron at concentrations of 0.26 and 0.52 mumol l-1 inhibited the formation of V79 colonies in a concentration-dependent way. Diminution of the size of colonies of the treated cells was accompanied by a decrease in protein content per cell. At the same time an increase in metabolic activity was observed. Benfluron blocked the V79 cells in S and G2 phases of the cell cycle and at higher concentrations induced cell lysis documented by alterations in cell membrane permeability and morphology. The in vitro membrane effect of benfluron involved a biphasic modulation of the cardiac sarcolemmal (Na+ + K+)-ATPase activity.  相似文献   
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Malignant transformation of skin epithelium caused by chronic wound exudation in the absence of osteomyelitis is a rare event. The paper reports a case of 50 year old Caucasian male who presented with an exophytic tumor on the right hand. The tumor rapidly developed within previous area of unhealed skin wound that had existed only for about 5 months. Histological examination of the excised tumor revealed highly differentiated squamous cell carcinoma (SCC). At that time of surgery nearby lymph node biopsy didn't reveal evidence for metastatic spreading. Patient underwent the limb salvage procedure with tumor resection followed by two stage, cross-flap skin plasty. This report indicates that there is a need to expand knowledge about SCC and about the treatment of the patients with these tumor by surgeons practicing in small medical centers.  相似文献   
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Two new genera and three new species of feather mites (Astigmata, Pterolichoidea, Analgoidea) are described from two closely related species of cockatoos, Cacatua galerita (type host) and C. sulphurea (Psittaciformes, Cacatuidae): Astrolabelichus caudatus gen. nov., sp. nov. (Pterolichidae), Psittophagus lacunosus sp. nov. (Pterolichidae), and Cacatualges microdiscus gen. nov., sp. nov. (Xolalgidae). The presence of the same set of mite species on these two species of parrots points to a very close affinity of Cacatua sulphurea and C. galerita and gives additional support for the recent hypothesis of the conspecificity of these birds.  相似文献   
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The management of staphylococcal diseases is increasingly difficult with present medical approaches. Preventive and therapeutic vaccination is considered to be a promising alternative; however, little is known about immune correlates of protection and disease susceptibility. To better understand the immune recognition of Staphylococcus aureus by the human host, we studied the antistaphylococcal humoral responses in healthy people in comparison to those of patients with invasive diseases. In a series of enzyme-linked immunosorbent assay analyses performed using 19 recombinant staphylococcal cell surface and secreted proteins, we measured a wide range of antibody levels, finding a pronounced heterogeneity among individuals in both donor groups. The analysis revealed marked differences in the antibody repertoires of healthy individuals with or without S. aureus carriage, as well as in those of patients in the acute phase of infection. Most importantly, we identified antigenic proteins for which specific antibodies were missing or underrepresented in infected patients. In contrast to the well-described transient nature of disease-induced antistaphylococcal immune response, it was demonstrated that high-titer antistaphylococcal antibodies are stable for years in healthy individuals. In addition, we provide evidence obtained on the basis of opsonophagocytic and neutralizing activity in vitro assays that circulating antistaphylococcal serum antibodies in healthy donors are functional. In light of these data we suggest that proper serological analysis comparing the preexisting antibody repertoires of hospitalized patients with different outcomes for nosocomial staphylococcal infections could be extremely useful for the evaluation of candidate vaccine antigens in addition to protection data generated with animal models.  相似文献   
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