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61.
Perioperative spasm of internal mammary artery is a common experience in coronary artery bypass grafting. Many techniques were described of harvesting the internal mammary artery to prevent vasospasm. We investigated the comparison of the contracting and relaxing responses of human internal mammary artery grafts harvested by two different methods. Patients were divided into two groups depending on the harvesting technique. In the first and second groups arteries were harvested by classical and carbon dioxide insufflation techniques, respectively. In both groups, endothelial function of arteries was assessed by precontracting the rings with phenylephrine (10(-5)M) and dilatating them by cumulative acetylcholine (10(-8) to 10(-5)M) concentrations. Cumulative concentration-response curves for phenylephrine (10(-8) to 10(-4)M), noradrenaline (10(-9) to 10(-4)M), and 5-hydroxytryptamine (10(-9) to 10(-4)M) were obtained in all groups. Endothelial integrity of arteries were histopathologically evaluated. In both groups, acetylcholine caused concentration-dependent relaxations in rings precontracted with phenylephrine (10(-5)M). In arteries harvested by carbon dioxide insufflation technique, acetylcholine caused significantly higher relaxations compared to the rings obtained by classical technique (p<0.05). In all rings of study groups, phenylephrine, noradrenaline and 5-hydroxytryptamine caused concentration-dependent contractions. There was not any significant difference in concentration-dependent responses of these contracting pharmacological agents between the groups. Histopathological evaluation revealed no major arterial damage in both groups. Carbon dioxide insufflation technique does seem not only to protect the integrity of the endothelium and the whole vessel, but also prevent the possible vasospasm of the internal mammary artery segments.  相似文献   
62.
We compared the efficacy and safety of a remifentanil (0.25 microg x kg(-1) x min(-1)-based balanced anaesthetic technique with a bupivacaine-based regional anaesthetic technique in an open label, multicentre study in 271 ASA physical status 1 or 2 children aged 1-12 years. Subjects requiring major intra-abdominal, urological or orthopaedic surgery were randomly allocated to receive either intravenous remifentanil (group R; n = 185) or epidural bupivacaine (group B; n = 86) with isoflurane/nitrous oxide for their anaesthesia. The majority of children in both groups (85% in group R, 78% in group B) showed no defined response to skin incision, and although the mean increase in systolic blood pressure (+11 mm Hg) was significantly greater in group R than in group B, this change did not represent a serious haemodynamic disturbance. More children in group R (31%) required interventions to treat hypotension and/or bradycardia than those in group B (12%), but these were easily managed by administration of fluids or anticholinergic drugs. Adverse events, mainly nausea and/or vomiting, occurred in 45% of group R and 42% of group B (NS). The adverse event profile of remifentanil in this study was typical of a potent mu-opioid receptor agonist. Remifentanil was as effective as epidural or caudal block in providing analgesia and suppressing physiological responses to surgical stimuli in children aged between 1 and 12 years undergoing major abdominal, urological, or orthopaedic surgery under isoflurane/nitrous oxide anaesthesia.  相似文献   
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64.
The technical name for a surgical sponge left in the body of a patient is inadvertent “gossypiboma.” The word is derived from the Latin word Gossypium for cotton and from the Kiswahili word boma for “place of concealment.” These retained sponges were first seen as “textilomas,” but were renamed “gossypiboma” in 1978. The first case was reported by Wilson in 1884. These are rarely are retrieved in the literature, because of legal complications. A higher incidence of retained laparotomy sponges has been reported in association with gynecological procedures. We report a case of gossypiboma in the 38th week of pregnancy that imitated an ovary neoplasm.  相似文献   
65.
PURPOSE: Erythropoietin, an oxygen-regulated glycoprotein hormone, is a hematopoietic cytokine that stimulates erythropoiesis by binding to its cellular receptor [erythropoietin receptor (EPOR)]. The recombinant form of human erythropoietin is used to prevent or treat anemia in cancer patients. However, in a recent randomized, placebo-controlled trial involving patients receiving curative radiotherapy for squamous cell carcinoma of the head and neck, erythropoietin treatment was associated with poorer locoregional progression-free survival. The purpose of our study was to determine whether EPOR and its ligand erythropoietin are expressed in primary head and neck cancer. We also investigated the hypothesis that erythropoietin expression in malignant cells may be associated with the presence of tumor hypoxia, an important factor involved in resistance to radiation treatment, tumor aggressiveness, and poor prognosis. EXPERIMENTAL DESIGN: Twenty-one patients received an i.v. infusion of the hypoxia marker pimonidazole hydrochloride before multiple tumor biopsies. Contiguous sections from 74 biopsies were analyzed by immunohistochemistry for EPOR and erythropoietin expression and pimonidazole binding. RESULTS: EPOR expression was present in tumor cells in 97% of the biopsies. Coexpression of erythropoietin was observed in 90% of biopsies. Erythropoietin and pimonidazole adduct staining did not always colocalize within tumors, but there was a significant positive correlation between levels of microregional erythropoietin expression and pimonidazole binding. CONCLUSIONS: The coexpression of erythropoietin and EPOR in tumor cells suggests that erythropoietin may potentially function as an autocrine or paracrine factor in head and neck cancer. The expression of the hypoxia-inducible protein erythropoietin in tumor cells correlates with levels of tumor hypoxia.  相似文献   
66.
Purpose:Functional epiphora is a clinical condition that presents with the complaint of watery eyes, but without anatomical stenosis in the lacrimal drainage system. Although the mechanism is not clear, there are various possibilities involving the movement of the orbicularis oculi muscle, especially its deeper segment (Horner’s muscle). We aimed to evaluate the function of the orbicularis oculi muscle in patients with patent, but dysfunctional lacrimal drainage system using a quantitative motor unit potential (MUP) analysis.Methods:Twenty-eight patients with functional epiphora (mean age = 59 years) and a control group of 28 volunteers were included in the study. Inclusion criteria were persistent and symptomatic epiphora or wiping >10 times per day and diagnosis confirmation by lacrimal irrigation test. Electromyography (EMG) was performed on the deeper segment of the orbicularis oculi muscle (medial and lateral parts). MUP parameters (duration time, amplitude, number of phases, number of turns, area, rise time, and thickness) were evaluated in both groups. Any increase in amplitude, prolongation time (>14 ms), number of turns, and satellite potential was taken as characteristic of the neurogenic type of epiphora, whereas shortened motor unit duration time, increased phase number, and low amplitude are the features of myopathic type.Results:Upon MUP analysis of the medial and lateral orbicularis oculi muscle, the increase in duration and thickness values in the medial part and the increase in duration, amplitude, area, and thickness values of the lateral part were found to be statistically significant in the patient group compared to the control group (P < 0.001). In the evaluation of the patients’ medial and lateral orbicularis oculi muscle, the increase in phase values and decrease in amplitude, area, and rise time values were found to be statistically significant (P = 0.024, P < 0.001, P < 0.001, and P = 0.010, respectively).Conclusion:These data show that functional epiphora is due to neurogenic damage of the orbicularis oculi muscle and should be investigated in more detail.  相似文献   
67.
68.
Monoarticular tuberculosis (TB) affecting the knee is rare in all forms of TB (0.1-0.3%). We present the case of a patient with tuberculous arthritis in whom the diagnosis was belated due to a lack of familiarity with the disease; here, we emphasize the difficulties associated with the diagnosing joint TB. A 20-year-old man was referred to our department due to swelling of the right knee and the presence of persistent, mild pain for 4 years. The lack of systemic evidence of this disease, the indolent course of disease, and the presence of non- specific symptoms renders early recognition of this disease difficult. Furthermore, in cases in which a diagnosis cannot be reached simply by culturing the synovial fluid, synovial biopsy cultures should be considered m the diagnostic process, due to the high rate of positivity of such cultures. The diagnosis and treatment of articular TB are both urgent matters; surgical debridement and strict adherence to antituberculous chemotherapy tend to yield a satisfactory functional outcome.  相似文献   
69.
BackgroundThe management of a solitary pulmonary nodule is a challenging issue in pulmonary disease. Although many factors have been defined as predictors for malignancy in solitary pulmonary nodules, the accurate diagnosis can only be established with the permanent histological diagnosis.ObjectiveWe tried to clarify the possible predictors of malignancy in solitary pulmonary nodules in patients who had definitive histological diagnosis.MethodsWe made a retrospective study to collect the data of patients with solitary pulmonary nodules who had histological diagnosis either before or after surgery. We made a statistical analysis of both the clinic and radiological features of these nodules with respect to malignancy both in contingency tables and with logistic regression analysis.ResultsWe had a total of 223 patients with a radiological diagnosis of solitary pulmonary nodule. Age, smoking status and pack years of smoking, maximum standardized uptake value (SUVmax), and radiological features such as solid component, spiculation, pleural tag, lobulation, calcification, and higher density were significant predictors of malignancy in contingency tables. Age, smoking status and smoking (pack/year), SUVmax, and radiological features including spiculation, pleural tag, lobulation, calcification, and higher density were the significant predictors in univariate analysis. However, multivariate analysis revealed only SUVmax greater than 2.5 (p < 0.0001), spiculation (p = 0.009), and age older than 61 years (p = 0.015) as the significant predictors for malignancy.ConclusionAge, SUVmax, and spiculation are the independent predictors of malignancy in patients with solitary pulmonary nodules.  相似文献   
70.
In hypersensitive reactions to native L‐asparaginase, either premedication and desensitization or substitution with polyethylene glycol conjugated asparaginase (PEG‐ASP) is preferred. Anaphylaxis with PEG‐ASP is rare. An 8‐year‐old girl and a 2.5‐year‐old boy, both diagnosed as having acute lymphoblastic leukemia, presented with native L‐asparaginase hypersensitivity and substitution with PEG‐ASP was preferred. They received a premedication (methylprednisolone, hydroxyzine and ranitidine) followed by desensitization with PEG‐ASP infusion. Both patients developed anaphylaxis with peg‐asparaginase. These are the first reported cases of anaphylactic reaction to PEG‐ASP, despite the application of both premedication and desensitization. Anaphylaxis with PEG‐ASP is very rare and premedication and desensitization protocols may not prevent these hypersensitive reactions.  相似文献   
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