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41.
Chronic viral hepatitis is the main cause of chronic liver disease, cirrhosis and hepatocellular carcinoma throughout the world. Hepatitis B virus (HBV) has mutagenic effects on somatic cells. HBV may be showing these mutagenic effects through its viral proteins or through integrating into host DNA. The aim of this study was to determine whether HBV has a genotoxic effect on host DNA or not. Peripheral blood lymphocytes of 31 chronic HBV patients and 20 chronic HBV carriers were cultured in order to make cytogenetic evaluation by observing chromosome breakage and cytological evaluation by the micronucleus (MN) test. Their results were compared with 20 healthy controls. For each individual, 100 metaphase chromosome spreads were analysed. Around 190-1091 binucleated cells were observed and MN were scored for each individual. Our results showed significantly higher frequencies of chromosome breaks in chronic HBV patients and in HBV carriers than in the control group. There was no difference in MN scores among HBV patients, HBV carriers and healthy carriers. Based on our data, we conclude that chronic HBV patients and carriers have chromosomal instability and that HBV carriers are as affected as patients because of their same chromosome breakage levels.  相似文献   
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Motor cortex excitability changes during imagery of simple reaction time   总被引:1,自引:0,他引:1  
Imagining motor actions is enough to enhance cortical motor excitability. However, the fact that execution of the motor task has to be inhibited should have a correlate on the extent of cortical excitability enhancement. Therefore, we examined the possible differences between real and motor imagery of simple reaction time tasks (SRT) in the facilitation of the motor-evoked potential (MEP) to transcranial magnetic stimulation (TMS) and in the reduction of short-interval intracortical inhibition (SICI) taking place before the movement onset. Thirteen healthy volunteers were requested to perform visual real or imaginary SRT tasks (rSRT and iSRT) with their dominant hand. For rSRT, subjects had to perform a rapid isometric squeeze as soon as possible after the imperative signal. For iSRT they had to imagine the same movement without actually doing it. Electromyographic (EMG) signals were recorded from the first dorsal interosseus (FDI) muscle. The mean EMG onset was calculated for each subject in rSRT trials. Single-and paired-pulse TMS (at an interstimulus interval of 2.5 ms) were applied at rest and at time intervals of −25, −50, −75, −100 and −125 ms before the expected real (rSRT) mean EMG onset. In rSRT there was a significant increase of MEP to single-pulseTMS at the intervals of −50 and −25 ms, and in iSRT at −50 ms in comparison to the rest condition. % SICI changes were significantly reduced at the intervals of −75, −50 and −25 ms, before EMG the onset in rSRT and at −50 and −25 in iSRT (P < 0.05) in comparison to % SICI changes at rest. The differences between MEPs to spTMS and MEP to ppTMS were significantly larger at rest, −125 and −100 ms intervals in rSRT, and at all intervals in iSRT. Imagining to move causes an increase in corticospinal excitability and a decrease in intracortical inhibition that follow a temporal profile similar to those observed with real movements. However, complete removal of SICI happened only in rSRT at the shortest intervals before the EMG onset. Such action may delineate new tool in motor rehabilitation of patients who have limitation to move.  相似文献   
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Human kallikreins (hKs) have been reported to be involved in human cancers, and several hKs are promising biomarkers of various cancers, such as prostate, ovarian, breast, and testicular cancer. In the present study, we aimed to evaluate the prognostic value of immunohistochemical expression of hK11 in patients with gastric cancer. The study included 55 (36 men and 19 women; 58 ± 10 years of mean age) patients with gastric cancer treated with surgery and adjuvant chemoradiotherapy. Tissue sections were evaluated immunohistochemically with a monoclonal anti-hK11 antibody. Of the 55 patients, 35 (63.6%) were hK11-positive and 20 (36.4%) were hK11-negative. Disease-free and overall survival rates were significantly higher in patients with hK11 positive than in those with hK-11 negative expression (24 months vs. 11 months, p: 0.043; 29 months vs. 13 months, p: 0.038, respectively). In conclusion, hK11 expression in gastric cancer appears to be associated with a better prognosis. hK11 may be a prognostic biomarker of gastric cancer. On the other hand, it is needed to elucidate the mechanisms underlying the regulation of hK11 expression in gastric cancer.  相似文献   
46.

Purpose

The gallbladder and the biliary tract are structures in close connection with the adjacent organs and may show a number of variations and anomalies. It is therefore important for surgical purposes to know their anatomy and variations in detail. Various methods are used in the imaging of the variations of the biliary tract and its pathologies, including ultrasonography, computed tomography; direct cholangiographic methods like endoscopic retrograde cholangiopancreatography, percutaneous transhepatic cholangiography, intravenous cholangiography and T-tube cholangiography, as well as indirect methods like magnetic resonance cholangiopancreatography (MRCP) or cholescintigraphy. The aim of this study is to investigate the frequency of the anatomic variations of the biliary tract using 3-T MRCP and to compare the findings with the data in the literature.

Materials and methods

For the purposes of this study, patients who underwent MRCP at our hospital (Dicle University Hospital) between November 2009 and February 2012 were investigated retrospectively. A total of 590 patients (between 6 and 88 years of age; mean age: 51 ± 9 years) were included in the study. The MRCP imaging was carried out with an magnetic resonance imaging (MRI) device supplied with 3-T magnetic power and by obtaining T2-weighted images through the single-shot fast spin echo technique using the standard body coil. The axial and coronal source images and the reformatted images were evaluated together in terms of the possible anatomic variations.

Results

Among the 590 patients included in the study, of 233 (39.5 %) showed anatomic variations at different levels in the intra- and extrahepatic biliary tracts. Among these variations, a right posterior hepatic duct insertion to the left hepatic duct at the level of the bifurcation has been observed in 71 patients (12.1 %), trifurcation was observed in 30 patients (5.1 %) and insertion into the main hepatic duct at the proximal aspect of the cystic duct was observed in 18 patients (3.1 %). At the level of the cystic duct, medial insertion of the cystic duct was viewed in 58 patients (9.8 %), distal medial insertion was seen in 40 patients (6.8 %), a short cystic duct was detected in 10 patients (1.7 %), pancreatobiliary junction anomaly was viewed in two patients (0.4 %) and duplicate anatomic variations have been observed in 42 patients (7.2 %).

Conclusion

MRCP studies conducted using 3-T MRI devices may reveal similar or greater numbers of variations when compared to the existing MRCP studies in the literature. 3-T MRI shows a couple of variations. Pointing out these anatomical variations before the surgical intervention may prevent possible iatrogenic traumas. Donors with unsuitable variations for liver transplant may be spotted out at an early phase through the MRCP and certain operations with a high morbidity rate may thus be avoided.  相似文献   
47.
Objective: Pseudotumor cerebri (PTC) is a clinical condition characterized by signs and symptoms of increased intracranial pressure, such as headache and papilledema. Our aim was to investigate the etiological and clinical features of pseudotumor cerebri (PTC) in children. Materials and method: We performed a comprehensive analysis of epidemiology, diagnostic work-up, therapy, and clinical follow-up in 42 consecutive patients. Results: Totally 42 patients diagnosed with PTC [27 (64.3%) females and 15 (35.7%) males] were included in the study. The average age of the symptoms onset was 10.79 ± 3.43 years (range from 12 months to 17 years). Obesity was found in eleven (26.2%) of them. Two of the patients had familial mediterranean fever, two of them had posttraumatic PTC. The following diseases were one patient, respectively; mycophenolate mofetil-induced PTC, hypervitaminosis A induced PTC, corticosteroid induced withdrawal due to nephritic syndrome, use of oral contraceptives, Guillain–Barre syndrome, urinary tract infection, varicella-zoster virus infection and dural venous sinus thrombosis associated with otitis media. The most common symptom was headache, recorded in 76.2% of the patients. All patients were treated medically. Three patients in our group also required a ventriculoperitoneal shunt. Conclusion: Pseudotumor cerebri is an avoidable cause of visual loss, both in adults and children. Pre-pubertal obese girls are more common. Medical therapy appeared to be successful in treating pediatric PTC in most patients. Nevertheless, despite adequate treatment, children can rarely experience loss of visual field and acuity; thus, prompt diagnosis and management are important.  相似文献   
48.
ObjectiveParalytic poliomyelitis (pPM) is clinically suspected in individuals experiencing a non-progressive syndrome of flaccid paralysis and atrophy as a sequel of an acute infection. Despite normal sensory perception, patients with pPM complain of pain more than matched siblings. Here, we studied the characteristics of evoked pain in a cohort of pPM patients using contact heat evoked potentials and psychophysical tests.MethodsFifteen patients with pPM and 15 controls were studied. Inclusion criteria were unilateral or asymmetric involvement of lower extremities. Mechanical, warm and heat pain perception thresholds and evoked pain were measured in both thighs. Contact heat evoked potentials were recorded from the vertex.ResultsMechanical and heat pain thresholds were significantly lower in the affected than in the less-affected leg or in the legs of controls. Evoked pain ratings were significantly higher in the affected leg than in either the less-affected leg or in controls. Evoked potentials were significantly higher in the affected than in the less-affected leg.ConclusionPatients with pPM have mechanical and thermal hyperalgesia, which suggests abnormalities in processing of somatosensory inputs in these patients.SignificanceThis phenomenon should be taken into account in the routine clinical evaluation and management of pPM patients.  相似文献   
49.
The aim of the study was to investigate the efficiency of ram seminal plasma and fetal calf serum on freezing of buck semen. Twenty ejaculates were collected using an electro-ejaculator and split into six groups. While FCS additive was not used in A1, A2 and A3 groups, 10% FCS was added to B1, B2 and B3 groups. These groups were then edited according to whether the buck or ram SP was involved. The design of the groups was done as follows: Group A1 (control 1), group A2 without buck SP, group A3 containing ram SP instead of buck SP. Groups B1 (control 2), B2 and B3 were the FCS added forms of these groups. Progressive sperm motility percentages in Group A1 and Group B2 were found to be higher when compared to the lowest Group B3. There were no significant differences between the groups in neither the levels of reactive oxygen species nor the enzyme and glutathione activities. In conclusion, the lack of statistical difference between the groups suggested that despite the supplements used but only when the buck spermatozoa structure was healthy, the cell could preserve acrosome, DNA and the integrity of membrane.  相似文献   
50.
Background : Establishment of good analgesia is of major concern in the postoperative period following adenotonsillectomy. The aim of this study was to compare the effects of ketamine, morphine and tramadol on postoperative pain after adenotonsillectomy in children. Methods : Sixty children (age 5–12 years) scheduled for adenotonsillectomy were randomized into four groups to receive intravenously (i.v.) either 0.5 mg·kg?1 ketamine hydrochloride (K), 0.1 mg·kg?1 morphine hydrochloride (M), 1.5 mg·kg?1 tramadol hydrochloride (T) or normal saline (S) in a volume of 4 ml during induction. After tracheal intubation 10 μg·kg?1·min?1 ketamine hydrochloride in group K and 0.6 ml·kg?1·h?1 saline i.v. in groups M, K and S were infused peroperatively. Postoperative analgesic requirements and side‐effects were recorded. Pain was assessed by the Numeric Rating Scale (NRS) and the Children's Hospital of Eastern Ontario Pain Scale (CHEOPS) scores. Results : Heart rate increased significantly peroperatively only in group K. NRS at first and fifth minute in group M and at first minute in group T and K and CHEOPS score at first, fifth, 15th and 60th min in group M were found to be significantly lower than in the control group. The time to first analgesic requirement was significantly longer in group M compared with ketamine and the control group. Six children in group M, nine in group T, 11 in group K and 15 in group S needed additional analgesics. Conclusions : Morphine hydrochloride 0.1 mg·kg?1 i.v. administered during induction of anaesthesia provides efficient pain relief in children undergoing adenotonsillectomy.  相似文献   
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