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OBJECTIVE: To determine the feasibility and effectiveness of laparoscopically assisted hysterectomy. DESIGN: A prospective study of the planned surgical procedure was carried out by two teams, each with two gynaecologists, who were experienced in operative laparoscopy. SETTING: The operations were carried out in a private hospital, where advanced operative laparoscopy equipment was available. PATIENTS: Seventeen patients were selected for the procedure, all of whom required hysterectomy for symptoms of pain or menorrhagia in association with uterine or other pelvic disease. Patients with carcinoma or uterine enlargement beyond 12 cm were excluded. PROCEDURE: Laparoscopically assisted hysterectomy was carried out by means of a video monitor, uterine manipulation by vaginal instrumentation, three or four abdominal punctures of less than 1 cm, and bipolar diathermy to secure vascular pedicles. The uterus was removed from the vagina by cutting vaginal skin and the cardinal ligaments. RESULTS: The operating time was 90-220 min, the blood loss was 30-200 mL, and the hospital stay lasted two to five days and convalescence two to four weeks. No serious complications occurred. CONCLUSIONS: Laparoscopically assisted hysterectomy may be valuable when adnexal or uterine abnormalities are present and vaginal hysterectomy is either contraindicated or more difficult. The procedure requires special equipment and may only be carried out by experienced gynaecological operative laparoscopists. Its acceptance will depend upon reducing the operating time to less than 90 min. It has the advantage of reducing the duration of hospital stay and the duration of convalescence when compared with abdominal hysterectomy.  相似文献   
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Nerve growth factor induces protein-tyrosine phosphorylation.   总被引:40,自引:11,他引:29       下载免费PDF全文
When the sympathetic nerve-like cell line PC12 is exposed to nerve growth factor (NGF), there is a rapid and transient phosphorylation of tyrosine residues in cellular proteins, as demonstrated by immunoblotting of cell extracts with high-affinity polyclonal antibodies specific for phosphotyrosine residues. Epidermal growth factor (EGF), which does not cause the morphological differentiation of PC12 cells that is produced by NGF, also induces protein-tyrosine phosphorylation. The methyltransferase inhibitor, 5'-methylthioadenosine, which is known to block the NGF-mediated morphological differentiation of PC12 cells, also inhibits the induction of protein-tyrosine phosphorylation by NGF. 5'-Methylthioadenosine has no effect, however, on EGF-stimulated phosphorylation of tyrosine residues in cellular proteins. In addition, low temperature markedly slows the rate of protein-tyrosine phosphorylation stimulated by NGF, but it has no effect on the time course of protein-tyrosine phosphorylation induced by EGF. These data suggest that NGF and EGF induce protein-tyrosine phosphorylation in PC12 cells by different mechanisms.  相似文献   
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Background  

Persisting neck pain is common in society. It has been reported that the prevalence of neck pain in office workers is much higher than in the general population. The costs to the worker, employer and society associated with work-related neck pain are known to be considerable and are escalating. The factors that place office workers at greater risk of developing neck pain are not understood. The aim of this study is to investigate the incidence and risk factors of work-related neck pain in Australian office workers.  相似文献   
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Knowledge of the factors that contribute to delay in seeking medical treatment for acute myocardial infarction (AMI) provides the basis for interventions that are intended to facilitate prompt care-seeking behaviour. However, operational definitions of delay time vary across research studies. The use of inconsistent cut-off times to distinguish between delayers and non-delayers is likely to compromise comparability and generalizability of the findings across studies. The purpose of this paper is to examine the impact of inconsistent operationalization of delay, in terms of cut-off times, on the validity of research findings pertaining to identifying its predictors. Secondary data analysis was performed using a sample of 73 patients who had recently experienced out-of-hospital AMI and concluded that their symptoms were related to the heart. Several regression models were built to examine the influence of using different cut-off times (1, 2, 3, 6, and 12 hours, median delay) on the number and nature of predictors ofAMI care-seeking delay.The impact of varying cut-off times on the explained variance, sensitivity, specificity, and predictive values associated with each regression model was examined. The use of different cut-off times produced different sets of independent predictors, which varied in number and nature.The variance explained by the different regression models as well as their classification indices varied. Use of different cut-off times for the definition of delay time led to inconsistent results. Thus, it is recommended that criteria be established among clinicians and researchers with regard to operationally defining care-seeking delay for AMI.  相似文献   
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Retained or recurrent stones in the common bile duct remain a clinical problem in 2% to 5% of patients undergoing cholecystectomy. Nonoperative extraction via the T tube tract or endoscopic sphincterotomy is successful in 85% to 95% of patients; however, the remainder require reoperation. This study evaluates the efficacy of electrohydraulic shock wave lithotripsy therapy of common duct stones too large to be extracted endoscopically or by T tube. Six patients were entered into the study. Ages ranged from 62 to 93 years. All patients either had severe preexisting systemic disorders or were of an advanced age. Stones ranged in size from 10 to 41 mm, with a mean largest dimension of 22 mm. In all patients either extraction by traditional nonoperative means failed or there was a stone that was considered to be too large to be extracted successfully. Patients were treated with 1200 to 2400 shocks at 16 to 20 kV. Five of six patients were treated with local anesthesia and sedation. Stones were successfully fragmented in all but one patient. Five patients required extraction of the remaining fragments either through the T tube tract (one patient) or via endoscopic sphincterotomy. All patients were free of stones at discharge, with the exception of one patient with severe cirrhosis who had an intrahepatic stone behind a right hepatic duct stricture. This stone had been successfully fragmented but an endoscopic retrograde cholangio-pancreatogram revealed some residual fragments despite normal alkaline phosphatase and bilirubin values. There were no hospital deaths, although the patient with the intrahepatic stone died of bleeding varices several months later. Electrohydraulic shock wave lithotripsy seems to be an effective adjuvant treatment in clearing the bile duct of stones that would otherwise require reoperation.  相似文献   
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Six-hundred and forty four radiation therapists from 21 European countries, Canada, and the USA responded to a questionnaire regarding the management of three cases of advanced cancer. The cases were a 64-year-old man with brain metastases from small cell carcinoma of the lung; a 64-year-old woman with bone metastases from carcinoma of the breast and a 59-year-old man with squamous cell carcinoma of the bronchus and mediastinal nodes. There was variation as to the perceived prognosis and appropriate aims of therapy, particularly for the case of squamous cell carcinoma of the bronchus. The total dose and number of fractions could be related to the perceived aims and expectations of treatment, for example, those aiming to extend life gave higher doses of radiotherapy and those aiming only to relieve symptoms gave lower. Similarly, those describing treatment as radical and estimating longer survival gave higher doses and more fractions than those treating palliatively. Variations in the role of the radiation oncologist in the management of advanced and metastatic cancer in the USA, Canada and Europe are discussed.  相似文献   
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