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991.
联合作用特征的评价   总被引:12,自引:1,他引:11       下载免费PDF全文
多年来 ,毒药理界对机体内多种外来化合物产生的联合作用缺乏统一评价体系。本文就其已有的理论基础和相关的方法学成就作一概述 ,旨在介绍各自的使用范围和优缺点 ,提请应用者根据条件选用合适的评价方法  相似文献   
992.
Summary Parasternal two-dimensional and Doppler echocardiography were compared with angiographic, surgical, and postmortem data in 213 patients with various forms of congenital heart disease for its accuracy in determining patency and anatomy of the ductus arteriosus (DA). The age range of the examined patients was from 1 day to 4 years (mean, 7.4 months). Echocardiography was always performed before any invasive procedure. An adequate window for imaging the DA was obtained by parasternal, two-dimensional echocardiography in 209 patients (98%). A persistent ductus arteriosus (PDA) was detected by invasive methods in 79 of 209 patients (38%), and by two-dimensional and Doppler echocardiography in 76 (sensitivity, 96%; specificity, 100%). The echocardiographic and angiographic findings agreed closely as to the duct's morphology. Our technique permits an accurate visualization of the duct in neonates, infants, and small children with various forms of congenital heart disease.  相似文献   
993.
Summary The evolution and advances of the lateral surgical approaches used for neoplasms of the cranial base involving the middle and posterior cranial fossa are reviewed. The lateral approaches available for access to the cranial base are diverse and are often used in combination. Approaches for tumors that are completely extradural, usually involving the temporal bone or infratemporal fossa, include the infratemporal fossa approach described by Fisch and the preauricular subtemporal-infratemporal fossa approach. Lateral approaches used to provide exposure of intradural tumors involving the clivus and traversing the middle and posterior cranial fossa are based on the following approaches: the frontotemporal orbitozygomatic, subtemporal/middle fossa, transpetrosal, lateral suboccipital, and transcondylar approaches. The great strides that have been made in the safe and effective surgical treatment of cranial base neoplasms are due, in part, to the availability of multiple surgical approaches and the ability to tailor the planned operative procedure to the precise location and extent of the cranial base tumor.  相似文献   
994.
作者自1989年至1991年采用颅侧例进路切除颅底深部广泛的良恶性肿瘤15例.结果表明,该进路可获得广泛的暴露和直视下手术.加之显微手术技术的应用提高了切除肿瘤的彻底性和安全性.切除侵入颈静脉球肿瘤时,结扎乙状窦和颈内静脉后还应用大量明胶海绵填塞岩下窦出血.随访6个月~30个月,除1例横纹肌肉瘤和1例鳞癌术后9个月颅内转移死亡外,其余均无复发.  相似文献   
995.
经眶额下入路行鞍区大型肿瘤切除术   总被引:3,自引:1,他引:3  
本文是在我们提出的“经眶-额,蝶窦-颅内联合入路”的基础上,进行改进的一种入路。其特征为操作更简便可行,易于推广,可以全切鞍区大型肿瘤。文中报告了手术方法,近2年来26例病人的手术结果,其中垂体腺瘤17例,颅管瘤7例,筛窦癌及鞍结节脑膜瘤各1例,肿瘤直径均在3cm以上,最大者达7cm,全切率达76.9%,所有病人情况良好。  相似文献   
996.
Complications of childbirth is a leading death cause for women of reproductive ages in the developing countries today. The unique Swedish population statistics from the 19th century permit comparable historical studies. In seven Swedish parishes 170 maternal deaths were observed - 595 per 100,000 live births. Eclampsia, obstructed labor and hemorrhage were responsible for 92 deaths, and puerperal sepsis for only 15 deaths. Indirect obstetrical deaths, like pneumonia, tuberculosis, dysentery and heart diseases, accounted for 30.8% (41/133) of the specified death causes. With a time limit of 1 year instead of 42 days following delivery, maternal mortality was increased by 17%. Out of 14 married women 1 died from childbirth. Maternal deaths accounted for 40-50% of all deaths in the central ages of reproduction, leaving the motherless children with a highly increased death risk. Of the live born, 3% survived 5 years after the mothers' death. Of children aged 1-5 only 13% survived 5 years after the mothers death.  相似文献   
997.
In 63 specimens, 74 aneurysms, and five other lesions, postmortem microsurgical and endoscopic inspection (PMI) was done. This work not only allowed for safe pathoanatomic findings, but moreover showed characteristics of a training method developed according to a model with clear standards. PMI gives training in: 1. Understanding of pathoanatomic topography and syntopy 2. Analysis of imaging findings 3. Analysis of approaches (approach planning) 4. Paraendoscopic methods (video surgery) 5. Clipping training 6. Analyzing the ergonomy of the setting and instrumentation In the series presented, aneurysms were the focus of attention. Postmortem inspection trains nearly all manipulative and cognitive abilities necessary for operative management of this difficult lesion. The acceptance and applicability of this method for resident training must be evaluated in the future. Electronic Publication  相似文献   
998.
999.
The purpose of this study was to review our experience with laparoscopic common bile duct (CBD) exploration by the transcystic approach and choledochotomy. We selected the transcystic approach for patients whose CBD stones were less than five in number and smaller than 9 mm in diameter, and whose CBD was less than 15 mm in diameter on cholangiograms. Among 217 patients with CBD stones treated laparoscopically, the transcystic approach was performed successfully in 91 of 104 patients in whom it was attempted (87.5%). The other 126 patients underwent laparoscopic choledochotomy, followed by ductal closure with transcystic drainage in 59, T-tube drainage in 46, primary ductal closure in 19, and choledochoduodenostomy in 1. Choledochotomy was converted to open surgery in only 1 patient. The transcystic approach was associated with shorter hospital stay and less morbidity than choledochotomy. However, choledochotomy also had an acceptably low rate of complications. Bile leaks occurred more frequently in those with primary ductal closure than in those with transcystic drainage or T-tube drainage. Residual stones were found in 2 patients with the transcystic approach and in 10 with choledochotomy. The residual stones were removed through the T-tube tract by choledochoscopy in 7 of these 10 patients. From these results we conclude that laparoscopic management of CBD stones is feasible for almost all patients with CBD stones. It is considered to be safe and effective and has the advantage of being a single-stage procedure. Received: July 7, 2000 / Accepted: October 26, 2000  相似文献   
1000.
Classical least-squares (CLS) and principal component regression (PCR) techniques were proposed for the simultaneous analysis of tablets containing acetaminophen and caffeine without using a chemical separation procedure. The chemometric calibrations were prepared by measuring the absorbances values at the 15 wavelengths in the spectral region 215-285 nm and by using a training set of the mixtures of both drugs in 0.1 M HCI. The obtained chemometric calibrations were used for the estimation of acetaminophen and caffeine in samples. The numerical calculations were performed with the 'MAPLE V' software. By applying two techniques to synthetic mixtures, the mean recoveries and the relative standard deviations in the CLS and PCR techniques were found as 99.5 and 1.29, 99.7 and 1.00% for acetaminophen and 99.9 and 1.92, 100.0 and 1.178% for caffeine, respectively. Our results were compared with those obtained previously by one of us considering HPLC method as a reference method. These two methods were successfully applied to a pharmaceutical tablet formulation of two drugs.  相似文献   
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