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The use of ultrasonically activated scalpel for tissue cutting and coagulation is a potential replacement for electrosurgery, which can be related to different complications. Its working principle is to transform the electric power into the mechanical longitudinal movement of the working part of the instrument, by a piezoelectric transducer situated in the hand piece. Between October 2000 and June 2004, six patients with abdominal cysts were treated by laparoscopy, using the harmonic scalpel. The average age was 40.8 (ranging from 15-60) years. Laparoscopic abdominal cyst fenestration was performed in five patients, and laparoscopic cholecystectomy and abdominal cyst fenestration were done in one patient during the same operation. The average duration of the operation was 40 (ranging from 25-70) minutes and hospital stay was 2.8 (ranging from 1-5) days. Laparoscopic abdominal cyst fenestration using the harmonic scalpel is a safe and successful operation, with good results including all the advantages of the minimally invasive surgery.  相似文献   
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Post-mitotic neurons are typically terminally differentiated and in a quiescent status. However, in Alzheimer disease (AD), many neurons display ectopic re-expression of cell cycle-related proteins. Cyclin-dependent kinase 11 (CDK11) mRNA produces a 110-kDa protein (CDK11(p110)) throughout the cell cycle, a 58-kDa protein (CDK11(p58)) that is specifically translated from an internal ribosome entry site and expressed only in the G(2)/M phase of the cell cycle, and a 46-kDa protein (CDK11(p46)) that is considered to be apoptosis specific. CDK11 is required for sister chromatid cohesion and the completion of mitosis. In this study, we found that the expression patterns of CDK11 vary such that cytoplasmic CDK11 is increased in AD cellular processes, compared to a pronounced nuclear expression pattern in most controls. We also investigated the effect of amyloid precursor protein (APP) on CDK11 expression in vitro by using M17 cells overexpressing wild-type APP and APP Swedish mutant phenotype and found increased CDK11 expression compared to empty vector. In addition, amyloid-β(25-35) resulted in increased CDK11 in M17 cells. These data suggest that CDK11 may play a vital role in cell cycle re-entry in AD neurons in an APP-dependent manner, thus presenting an intriguing novel function of the APP signaling pathway in AD.  相似文献   
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Amitraz is formamidine pesticide widely used as insecticide and acaricide. In veterinary medicine, amitraz has important uses against ticks, mites and lice on animals. Also, amitraz is used in apiculture to control Varroa destructor. It this study, the alkaline Comet assay was used to evaluate DNA damaging effects of amitraz in human lymphocytes. Isolated human lymphocytes were incubated with varying concentrations of amitraz (0.035, 0.35, 3.5, 35 and 350 μg/mL). The Comet assay demonstrated that all concentrations of amitraz caused statistically significant increase in the level of DNA damage, thus indicating that amitraz possesses genotoxic potential. The concentration of amitraz that produced the highest DNA damage (3.5 μg/mL) was chosen for further analysis with the antioxidant catalase. The obtained results showed that co-treatment with antioxidant catalase (100 IU/mL or 500 IU/mL) significantly reduced the level of DNA damage, indicating the possible involvement of reactive oxygen species in DNA damaging effects of amitraz. Flow cytometric analysis revealed increase of the apoptotic index following treatment with amitraz. However, co-treatment with catalase reduced the apoptotic index, while treatment with catalase alone reduced the percentage of apoptotoc cells even in comparison with the negative control. Therefore, catalase had protective effects against ROS-mediated DNA damage and apoptosis.  相似文献   
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The role of lipids in the aetiology and progress of Alzheimer's disease (AD) is still unclear High lipid levels could be one of the risk factors for AD, but no association or even protective effects of high cholesterol levels in the development of the AD were also found. The aim of the study was to determine serum levels of total cholesterol, high-density-lipoprotein cholesterol (HDL-C), low-density-lipoprotein cholesterol (LDL-C) and triglycerides (TG) in female patients with AD and in healthy elderly controls. The 50 patients met the diagnostic criteria of probable AD according to the NINDS-ADRDA and DSM-IV criteria. Cognitive impairment was evaluated using the Mini Mental State Examination (MMSE). Patients were subdivided into two groups of 19 patients in the middle (MMSE 10-19) and 31 patients in the late (MMSE 0-9) phase ofAD. Psychotic and non-psychotic features, evaluated by means of Neuropsychiatric Inventory, were presented in 13 and 37patients with AD, respectively. Control group consisted of 58 subjects without cognitive impairment (MMSE >27) and with lipid levels within normal range. Serum lipid levels were determined by the enzymatic colour tests and by the enzymatic clearance assay. Significantly lower lipid levels were found in patients with AD, than in controls. Patients in the late phase of AD had significantly lower entire lipid profile than controls and significantly lower cholesterol and LDL-C levels than patients in the middle stage ofAD. There was no difference in lipid levels between patients with and without psychotic features. The significant positive correlations were found between MMSE scores and cholesterol, LDL-C levels and age in all AD patients. The results support the presumption that lipid profile might be connected with the aetiology and progress of AD and showed the association between low serum cholesterol and LDL-C levels and cognitive decline in patients with AD. Further studies are needed to confirm the relationship between lipid levels and cognition, and to validate the lipid profile as a biological marker for the progress of AD.  相似文献   
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The aim of this study is to determine the word frequency for all thirty letters of the Croatian alphabet and to collect normative data for the letter fluency task in Croatian speakers. Ninety two healthy participants were given each of the Croatian letters, and asked to generate as many words as possible in 60 seconds for each letter Results suggested that participants generated most frequently words starting with the letters as follows: "K", "P", "S" and "M".  相似文献   
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Thyroid hormones enhance the metabolic rate and the aerobic metabolism favoring oxidative stress, which is accompanied by induction of damage to cellular macromolecules including the DNA. The aim of the present study was to investigate the ability of thyroxine to induce sister chromatid exchange and micronuclei, and to modulate cell-cycle kinetics in cultured human lymphocytes. Eight experimental concentrations of thyroxine were used, ranging from 2 x 10(-9) to 0.5 x 10(-4)M. Treatment with thyroxine increased the frequency of SCE per cell at the higher concentrations (1.5 x 10(-6), 0.5 x 10(-5), 1.5 x 10(-5) and 0.5 x 10(-4)M). On the other hand, there were no significant aneugenic and/or clastogenic effects observed in the cytokinesis-block micronucleus assay. The results show that thyroxine acted as a relatively weak clastogen compared with the positive control N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). In addition to the genotoxic effects, two high concentrations of thyroxine decreased the mitotic index and caused cell-cycle delay. In conclusion, thyroxine exhibited weak clastogenic effects only at high concentrations. Therefore, effects in humans might appear in cases of acute thyroxine overdose.  相似文献   
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Post mortem brain studies indicate that alterations in serotonergic and catecholaminergic systems might be associated with Alzheimer's disease (AD). The aim of the study was to determine serotonin (5-HT) levels and monoamine oxidase type B (MAO-B) activity in platelets of psychotic and non-psychotic patients with AD, established according to the NINCDS-ADRDA and DSM-IV-TR criteria. Cognitive impairment and psychotic features were evaluated using Mini Mental Status Examination and Neuropsychiatric Inventory. Platelet 5-HT concentration and MAO-B activity were determined spectrofluorimetrically in 116 (51 male, 65 female) healthy subjects and 70 psychotic (10 male, 60 female) and 151 non-psychotic (32 male, 119 female) patients. Psychotic and non-psychotic female and psychotic male patients had significantly lower platelet 5-HT concentration than corresponding sex matched control subjects. Platelet MAO-B activity was significantly increased in both male and female non-psychotic patients compared to the sex matched controls. Non-psychotic female patients had significantly higher platelet MAO-B activity than psychotic female patients. Our data suggest that platelet MAO-B activity, but not platelet 5-HT concentration, could differentiate between psychotic and non-psychotic subtypes of AD.  相似文献   
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The aim of this research was to investigate whether or not sugar dusting can stimulate the grooming behaviour in Apis mellifera L. (Hymenoptera: Apidae), an important defensive mechanism against Varroa destructor Anderson & Trueman (Acari: Varroidae), and to assess the most effective dose and frequency of treatment. The criterion for evaluation of grooming potential was the percentage of damaged mites (PDM) among the total number collected on the bottom boards of the hives. In each sugar‐treated group PDM was significantly higher in comparison both with the negative control (no treatment) and with the values preceding the treatment. The results point to a stimulating effect of sugar on the grooming behaviour at all doses and frequencies tested. Treatment frequency influenced the stimulating effect of sugar: treatments at 3‐ and 7‐day intervals with 30 and 40 g resulted in significantly higher PDMs than the least frequent treatment (every 14 days); dusting with 20 g influenced PDM only when repeated at 3‐day intervals. Because treatments at 3‐day intervals are time‐consuming, those with 40 or 30 g repeated every 7 days may be recommended. In the positive control (hives treated with amitraz), average PDM was significantly lower than in the negative control and all sugar‐treated groups. Possible causes of the stimulating effect of sugar dusting on bee grooming behaviour are discussed.  相似文献   
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