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21.
The dose-dependent effect of acute zimeldine and alaproclate treatment upon the acquisition of two-way and one-way active avoidance in the rat was studied in a single-session and in a repeated-sessions design. Zimeldine (5–20 mg/kg, IP), but not alaproclate, caused disruptions of two-way avoidance acquisition. Acquisition deficits were also caused by citalopram and fluoxetine but not the other antidepressant drugs tested. Zimeldine, but not alaproclate or desipramine, caused a slight but non-significant impairment of one-way active avoidance; neither zimeldine nor alaproclate produced any effects upon fear conditioning and retention testing. The long-term action of p-chloroamphetamine (2×10 mg/kg) antagonised the acute zimeldine effect totally, and chronic treatment with zimeldine (15 days, 1×50 mol/kg) and chlorimipramine (15 days, 2×10 mol/kg) also caused some partial blockade of the two-way avoidance deficit. These data seem to suggest some involvement of serotonin (5-HT) in the observed disruptions of two-way active avoidance caused by acute zimeldine treatment.  相似文献   
22.
Male infertility is a global health problem, and the underlying molecular mechanisms are not clearly known. Ion channels and microRNAs (miRNAs), known to function in many vital functions in cells, have been shown to play a significant role in male infertility through changes in their expressions. The study aimed to evaluate the alterations of testicular and/or spermatozoal potassium voltage-gated channel subfamily J member 11 (KCNJ11), Cystic fibrosis transmembrane conductance regulator (CFTR), miR-let-7a and miR-27a expressions in carbamazepine-related male infertility. Here, we showed that carbamazepine reduced sperm motility, increased abnormal sperm morphology, and impaired hormonal balance as well as increased relative testis weight and decreased relative seminal vesicle weight. On the other hand, downregulated KCNJ11 and upregulated miR-let-7a expressions were determined in testis (< .05). Also, downregulated KCNJ11 and upregulated CFTR and miR-27a expressions were found in spermatozoa (< .05). Interestingly, altered testicular KCNJ11 and miR-let-7a expressions were correlated with decreased sperm motility and elevated sperm tail defect. Besides, spermatozoal CFTR and miR-27a expressions positively correlated with sperm tail defects. The results indicated a significant relationship between ion channel and/or miRNA expression alterations and impaired sperm parameters due to carbamazepine usage.  相似文献   
23.
Postoperative infection after hip joint replacement is an uncommon but potentially devastating complication in contemporary orthopaedics. Management in two stages is the more favored approach in North America. This introduces difficulty with patient management in the interval between stages, delays rehabilitation, and introduces technical difficulty during the second stage. A method has been developed whereby a temporary antibiotic-loaded facsimile of the hip is introduced at the first stage, designed to maintain stability of the joint, length of the limb, and mobility of the patient. It has been used in a total of 86 cases to date. The results in 46 cases with a minimum follow-up of 2 years are reviewed in this article. The infection was controlled in 93.5% of cases.  相似文献   
24.
Between 1983 and 1993, 41 patients underwent a first-stage Belt-Fuqua operation for penile hypospadias repair and 39 completed the second stage. Minor complications were observed after the first stage. The primary success rate following the second stage was 82%. Major complications noted after the second stage consisted mainly of fistula formation. The surgical technique is described and alternative methods are discussed.  相似文献   
25.
Twenty-seven children with mumps or chickenpox were taken as a model to evaluate the haematological consequences of viral infections including serum iron status. Blood samples were obtained from all patients at presentation and on the 21 st day of the disease. While haemoglobin, haematocrit, and meam corpuscular volume levels were similar in two measurements (P>0.05), the mean leucocyte, absolute lymphocyte and thrombocyte counts, mean serum iron, serum iron binding capacity and transferrin saturation levels were lower at presentation than on the 21 st day of the disease. The serum iron levels were below 30 g/dl in 16 (59.2%) patients at presentation while only 4 (14.8%) had low values on 21 st day. Twenty-four (88.9%) patients had an increment in the serum iron binding capacity levels and 2 (7.6%) reached values above the normal range on the 21 st day. Int 21 (77.8%) patients, the transferrin saturation levels were below the expected ranges at presentation but 26 (96.3%) showed an increment on the 21 st day. However, the mean ferritin level was higher at presentation. Therefore, during the evaluation of patients for anaemia, the presence of a recent acute viral infection should be documented so as to avoid unnecessary iron medication.  相似文献   
26.
It is known that polycythemia decreases the fluidity of the blood and impairs tissue perfusion due to red-cell sludging in the microcirculation. In this study, the effect of polycythemic hyperviscosity (PH) on bowel necrosis was evaluated in an experimental model of intestinal ischemia. Twenty-eight Wistar albino rats (90–170 g) were divided into two groups: group 1 was transfused to create hyperviscosity and then intestinal ischemia was produced (n = 16); in group 2 ischemia was produced without transfusion (n = 12). Intestinal ischemia was produced by clamping the superior mesenteric artery and the collateral arcades of the right colic artery for 30 min. Gross and histopathologic evaluations were performed by either immediate necropsy or relaparotomy 24 h later. Microscopic findings were graded from 0 to 3 according to the degree of ischemic changes. In group 1, 2 animals (12.5%) died before 24 h postoperatively; coagulation necrosis with grade 2 or 3 ischemic changes was observed in 10 animals (62.5%). In group 2 only a few hypertrophied Peyer's patches and capillary dilation were found, and all histopathologic changes were between grades 0 and 1. The difference between the histopathologic gradings of the two groups was significant (P < 0.001). It appears that in addition to reduced splanchnic blood flow, a secondary effect of PH is needed to induce ischemic coagulation necrosis. PH of the newborn must be considered a risk factor for necrotizing enterocolitis, so-called spontaneous intestinal perforations, and even intestinal atresia.Presented at the 1st European Congress of Pediatric Surgery, Graz/Austria, May 4–6, 1995  相似文献   
27.
To understand further the role of trace elements in the pathogenesis of febrile convulsions, serum zinc (Zn), copper (Cu), magnesium (Mg) and CSF Zn, Cu, Mg and protein levels were measured by spectrometry in patients with febrile convulsion (n=19), bacterial meningitis (n=9), viral CNS infection (n=16) and in the control groupn=10) which consisted of children with signs of meningeal irritation due to upper respiratory tract infection but normal CSF findings. Samples were obtained within 6 h after admission to hospital. Mean serum and CSF Zn levels in the febrile convulsion group were significantly lower than in the other groups (for serum Zn: 0.66±0.03 mg/l vs 0.98±0.07 mg/l, 1.06±0.08 mg/l, 1.05±0.09 mg/lP<0.05; for CSF Zn: 22.96±1.62 g/l vs 75.47 ±6.9 g/l, 50.32±5.235 g/l, 39.85 ±2.81 g/lP<0.05). A linear relationship was established between serum Zn and CSF Zn levels (P<0.001). Mean CSF Zn, Cu and protein levels in the bacterial meningitis group were significantly higher than in the other groups (for CSF Cu 63.94±6.33 g/l vs 38.77±2.70 g/l, 35.84±3.48 g/l, 33.86±2.88 g/lP<0.05; for CSF protein 0.80 ± 0.12 g/l vs 0.22±0.02 g/l, 0.53±0.08 g/l, 0.19±0.01 g/lP<0.05). In children with meningitis, the elevation of the mean CSF Zn and Cu levels may result from the breakdown of the blood-brain barrier and subsequent leakage of trace elements and protein from serum to CSF. There was no significant difference between the four groups in terms of mean serum Mg and mean CSF Mg levels.Conclusion Serum and CSF Zn levels are decreased in children with febrile seizures. Zinc deprivation may play a role in the pathogenesis of febrile seizures.  相似文献   
28.
Until recently the only way to rescue masked epitopes in routinely processed surgical pathological material was enzymatic digestion. The use of heat for antigen retrieval, first by microwave irradiation, represents an important breakthrough in immunohistochemistry. With the acceptance of microwave oven pretreatment, various modified techniques and alternative heating methods have also been proposed. Wet autoclave pretreatment for tissue proteolysis is a highly reliable alternative to the microwave antigen retrieval technique. It provides uniform heating of the slides, hence an even enhancement of staining intensity in a variety of formalin-sensitive antigens, and it also offers consistent interlaboratory results. The method has been introduced in routine diagnostic immunohistochemistry for the detection of estrogen-and progesterone receptors, L26-, Ki-67- and bcl-2 antigens and variable types of cytokeratins (1/5/10/11, 8, 13, 19). Experimentally, wet autoclaving can be used very successfully for the immunophenotyping of p53 and mdm2 expression, for the detection of adhesion molecules (CD44, integrins) and some anti-inflammatory molecules (annexins), among others. It has produced a substantial improvement in the visualisation of silver-stained nucleolar organizer regionsassociated proteins (AgNORs) in routine paraffin sections and along with modified silver staining and standardized AgNOR parameters assessed by image analysis. Wet autoclaving-based AgNOR staining has been proposed by a European multicentric study group as the standardized method for AgNOR analysis in archival material.  相似文献   
29.
Formalin fixed and paraffin embedded samples from 36 squamous cell carcinomas of the larynx and the oral cavity (pT2N0M0, R0) surrounded by non-tumorous mucosa were studied immunohistochemically using a panel of four different anti-p53 antibodies (CM1, PAbl801, D07, PAb240), a monoclonal anti-mdm2 antibody and MIB1, following wet autoclave antigen retrieval. P53 immunoreactivity was detected in 11/14 laryngeal and in 9/22 oral carcinomas. All p53 positive oral, and all but one laryngeal tumors revealed mdm2 positivity as well, whereas in p53 negative tumors 4/12 and 1/3 mdm2 immunopositive cases were demonstrated, respectively. MIB1 labeling indices of the tumors ranged between 18% – 64% in p53 positive cases, and 10% – 53% in p53 negative ones. The difference was not statistically significant. Close spatial coexpression of p53, mdm2 and MIB1 immunoreactivity was observed at the invasive front of the carcinomas and in the basal and suprabasal layers of the non-tumorous epithelium in all p53 positive cases. However, the MIB1 expression was similarly increased at the invasive margins in carcinomas lacking immunohistochemically detectable p53 alterations. Our results strongly suggest that p53 overexpression does not necessarily correspond to increased rate of proliferation, but rather to mdm2 overexpression and is largely dependent on the anatomical site in case of small and localized squamous cell carcinomas of the head and neck region.  相似文献   
30.
Hydatid disease is one of the world's most important health problems. Although several conservative approaches have been used for the management of this condition, surgery remains the ideal choice in most of the cases. Videolaparoscopic approach can safely be applied for the management of liver hydatid cysts if several precautions are undertaken. In this study, we present two liver hydatid cyst cases successfully treated with partial cystectomy and omentoplasty using videolaparoscopic approach.  相似文献   
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