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A case is described of a previously healthy obese woman in her fourth pregnancy who presented for caesarean section due to cephalopelvic disproportion (CPD). Forty minutes after a spinal anaesthetic a healthy child was delivered. Shortly after the injection of ergometrine and Syntocinon into the uterus, the patient described a general feeling of discomfort which was followed by convulsions and cardiac arrest. Resuscitation was successful and the circulation was restored. However, it was difficult to maintain oxygenation and the patient was mechanically ventilated for 24 hours and subsequently supplementary oxygen therapy was given for three days. A pulmonary scintigram on the fourth day after delivery showed large uptake defects indicative of pulmonary embolism. The patient recovered completely and was discharged home after two weeks. Differential diagnosis and measures to reduce the risk of deep vein thrombosis (DVT) are discussed.  相似文献   
176.
Objectives To evaluate the efficacy of early arytenoid adduction in the management of vagal paralysis after skull base surgery. Study Design Retrospective evaluation at a tertiary care skull base center. Methods Aggressive surgical management of skull base lesions has become increasingly popular owing to advances in surgical technique and intraoperative monitoring. Temporary and permanent lower cranial neuropathies occur frequently, especially after the surgical management of lesions involving the vertebrobasilar system and the jugular foramen. An injury to the proximal vagus nerve is usually associated with dysphonia and swallowing dysfunction. An early arytenoid adduction has been employed in 26 patients with a vagal paralysis after skull base surgery. Most commonly, the neurosurgical patient underwent an arytenoid adduction under general anesthesia on postoperative day 2. Results Videostroboscopy after arytenoid adduction demonstrated 76% of patients had complete glottic closure. Of those with inadequate glottic closure, all demonstrated a well‐medialized posterior glottis with a persistent anterior glottal gap. These patients were easily treated with a secondary type I thyroplasty under local anesthesia with sedation resulting in complete glottic closure. Despite excellent voice outcomes, 66% of these patients had dysphagia requiring enteral feedings for nutritional support. Conclusions An early arytenoid adduction is an excellent medialization technique that can be performed safely in the early postoperative period under general anesthesia after skull base surgery.  相似文献   
177.
Radical neck dissection is a standard procedure carried out for the teatment of palpable nodes in the neck but if carried out electively in cases where there are no palpable nodes in the neck it is considered to be an overtreatment with its associated morbity. Lateral neck dissection was carried out on twenty patients who had T31 T4 lesion of the larynx and hypophar-vnx with NO neck. The dissection entails removal of Level II. III and IV nodes. Occult metastasis 80% and 85% respectively. The mean follow up was 13 monts. It appears from our study that elective lateral neck dissection is a promising and safe procedure and may be useful as an important prognostic tool in sampling the lymph nodes and predicting recurrences in the neck.  相似文献   
178.
Mandibular resection for oral cancers has significant aesthetic and functional sequelae. A reliable preoperative predictor of mandibular invasion is required to guide the need for and extent of mandibular resection. An orthopantomogram of the mandible is an accurate, reliable, cost-effective predictor of bony involvement except for central arch lesions. The feasibility of outer table rim mandibulectomy alone in patients with floor of mouth tumors needs to be examined carefully. Received: 11 December 1998 / Accepted: 7 October 1999  相似文献   
179.
Phorbol ester protein kinase C (PKC) activators and PKC isozyme over-expression have been shown to significantly reduce intracellular accumulation of chemotherapeutic drugs, in association with the induction of multidrug resistance (MDR) in drug-sensitive cancer cells and enhancement of drug resistance in MDR cancer cells. These observations constitute solid evidence that PKC plays a significant role in the MDR phenotype of cancer cells. PKC-catalyzed phosphorylation of the drug-efflux pump P-glycoprotein was recently ruled out as a contributing factor in MDR. At present, the sole drug transport-related event that has been identified as a component of the role of PKC in MDR is PKC-induced expression of the P-glycoprotein-encoding gene mdr1. The objective of this study was to test the hypothesis that PKC can modulate the uptake of chemotherapeutic drugs in cancer cells independently of P-glycoprotein. We analyzed the effects of selective PKC activators/inhibitors on the uptake of radiolabelled cytotoxic drugs by cultured human colon cancer cells that lacked P-glycoprotein activity and did not express the drug efflux pump at the level of message (mdr1) or protein. We found that the selective PKC activator 12-O-tetradecanoylphorbol-13-acetate (TPA) significantly reduced uptake of [14C] Adriamycin and [3H] vincristine in human colon cancer cells devoid of P-glycoprotein activity, and that PKC-inhibitory N-myristoylated PKC- pseudosubstrate synthetic peptides potently and selectively induced uptake of the cytotoxic drugs in the phorbol ester-treated and non-treated colon cancer cells. TPA treatment of the cells did not induce expression of either P-glycoprotein or its message mdr1. In contrast with [14C]Adriamycin and [3H] vincristine uptake, [3H] 5-fluorouracil uptake by the cells was unaffected by TPA and reduced by the PKC-inhibitory peptides. These results indicate that PKC activation can significantly reduce the uptake of multiple cytotoxic drugs by cancer cells independently of P-glycoprotein, and that N-myristoylated PKC- pseudosubstrate peptides potently and selectively induce uptake of multiple cytotoxic drugs in cultured human colon cancer cells by a novel mechanism that does not involve P-glycoprotein and may involve PKC isozyme inhibition. Thus, N-myristoylated PKC- pseudosubstrate peptides may offer a basis for the development of agents that reverse intrinsic drug resistance in human colon cancer.  相似文献   
180.
Serum cholesterol, triglycerides and total lipids were estimated in twelve students exposed to varying degree of examination stress. Serum cholesterol and triglycerides exhibited a rise proportional to degree of examination stress whereas total lipids exhibited an initial rise followed by a fall. Values of all these parameters attained control level when the stress was over. The rise in serum cholesterol and triglycerides seems to be due to stress induced changes in hormonal levels and peripheral lipolysis respectively.  相似文献   
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