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11.
目的:研究中国安氏Ⅰ类错成人与美国安氏Ⅰ类错白人牙颌颅面形态结构的差异。方法:从西安市11所大学2098名新生中选取符合标准的101名(男53名、女48名)安氏Ⅰ类错样本。拍摄头颅定位X线片,用第四军医大学口腔医学院头影测量软件测量,用Alabama分析法与美国安氏Ⅰ类错白人颅颌面测量结果进行比较分析。结果:中国西安地区安氏Ⅰ类错成人上下颌突度大,面型较突;平面倾斜度、上下中切牙倾斜度及下中切牙至NB线距均较大;Y轴相对SN平面夹角增大,生长方向为后下。结论:与美国安氏Ⅰ类错白人比较,中国西安地区安氏Ⅰ类错成人颅面结构呈现颌骨突度大、下切牙唇倾及下颌趋向后下等特征。  相似文献   
12.
Background Although there have been reports dealing with ventricular diverticulum (VD) analyzed by cisternography and computed tomography (CT), those focusing on magnetic resonance imaging (MRI) or neuroendoscopic findings are rare. Case report We present a case of noncommunicating hydrocephalus caused by aqueductal stenosis with cystic lesion located in supracerebellar region. Third ventriculostomy was performed on this case. The conventional CT and MRI were compatible with usual VD, but neuroendoscopic examination suggested otherwise. The endoscopic view inside of the cystic lesion demonstrated passing veins and no membrane. We diagnosed this cystic lesion as a unique subtype of advanced VD mimicking spontaneous ventriculostomy. Endoscopic observation of the cyst was very useful for accurate diagnosis and safe treatment.  相似文献   
13.
Although cardiac arrhythmias remain a serious clinical problem in many patients with heart disease, the exact role of antiarrhythmic drug therapy is currently under intense evaluation. Within the last several years it has become clear that there are significant risks as well as potential benefits associated with existing agents. Ongoing studies in large patient populations should help determine the benefit/risk ratio of traditional therapy. Regardless of the outcome of these trials, current electrophysiological dogma will have to be re-evaluated and newer concepts evolve for drug development to make further progress. The goal of this symposium is to exchange information among basic and clinical investigators so as to facilitate the emergence of novel electrophysiological concepts that will form the basis for future generations of antiarrhythmic drugs.  相似文献   
14.
15.
In activated murine B lymphocytes, immunoglobulin class switch recombination occurs as a highly regulated process which is targeted to distinct switch regions. Here we present first evidence that in human B lymphocytes, switch recombination is targeted to distinct switch regions as well. In a panel of clonally unrelated IgG1-expressing human B cells, immortalized by Epstein-Barr virus (EBV) transformation, seven out of nine cells show switch recombination between Sμ and Sγ1 on both alleles, the active and inactive one. The remaining cells show no switch recombination on the inactive IgH locus. The very strong correlation of switch recombination on both alleles of IgG1-expressing cells proves that class switch recombination to IgG1 is not random but directed in human B lymphocytes.  相似文献   
16.
用单光子吸收法对足月孕妇尺、桡骨骨矿物质含量(BMC)、骨面密度(BMC/BW)进行测定及作血清钙、磷的生化测定。结果显示:足月孕妇的尺、桡骨骨矿物质含量、骨面密度明显低于同年龄组的未孕妇女。主要因为妊娠胎儿的骨胳生长发育,需要孕妇向胎儿输送大量的钙离子,若母亲对钙摄入不足或吸收不良,则造成孕妇的骨矿物质含量降低,骨质疏松;而孕妇血清钙、磷降低不明显。  相似文献   
17.
Objective To describe the different imaging modalities used for the diagnosis and classification of hydrocephalus, their role in defining the optimal treatment of hydrocephalus and to define the optimal preoperative diagnostics for endoscopic third ventriculocisternostomy (ETV). Methods An overview on available imaging modalities for hydrocephalus will be given and their pros and cons discussed. In addition, different aspects of the treatment of hydrocephalus by shunts and by ETV will be highlighted. Discussion The role of the technical aspects of performing an ETV, the role of the surgeon’s philosophy, the role of the urgency of the procedure, and the role of informed consent on the requirements for the imaging of the hydrocephalus will be discussed. Conclusion The authors conclude that MRI is a conditio sine qua non for ETV in elective surgical cases.  相似文献   
18.
Postpartum hemorrhage today: ICM/FIGO initiative 2004-2006.   总被引:3,自引:0,他引:3  
Postpartum hemorrhage (PPH) is the main cause of maternal mortality. Yet, even though solutions have been identified, governments and donor countries have been slow to implement programs to contain the problem. While poverty and low educational level remain the underlying cause of PPH, the current literature suggests that active management of the third stage of labor can prevent it. The International Confederation of Midwives (ICM) and the International Federation of Gynecology and Obstetrics (FIGO) are attempting to address the chronic PPH crisis by educating their members on best practices and on troubleshooting where resources are inadequate. Some studies found oxytocin to be preferable to misoprostol in settings where active management is the norm. However, secondary clinical effects may prove more troublesome with oxytocin than with misoprostol, and misoprostol may prove to be more practical and equally effective in low-resource settings. Two new interventions are also proposed, the anti-shock garment and the balloon tamponade.  相似文献   
19.
Polymorphism analysis of four canine MHC class I genes   总被引:1,自引:0,他引:1  
Abstract: We have studied the variability of four structurally complete dog leukocyte antigen (DLA) class I genes, termed DLA-12, -88, -79 and -64, in a population of mixed breed, unrelated dogs. The human HLA and canine DLA loci share a high degree of similarity in terms of gene structure. This analysis focused on the first three exons of each of four complete canine genes. Exons two and three are the major source of polymorphism in the corresponding human genes. In this analysis, DLA-88 was found to be significantly more polymorphic than the other three genes, with 44 distinct alleles observed among 63 mixed breed, unrelated dogs. The remaining genes had between one and four alleles when examined in 25 dogs. This work was carried out as part of an effort to develop an MHC typing system for the dog, which is critical to the further development of preclinical studies of hematopoietic stem cell and solid organ transplantation in the canine model.  相似文献   
20.
Summary In order to avoid invasive procedures (transfrontal, transcallosal) in the surgical treatment of colloid cysts the stereotactic aspiration technique was introduced by Bosch, RÄhn and Backlund in 1978. The viscosity of the intracystic colloid and the displacement of the cyst away from the aspiration needle are possible reasons for unsuccessful aspiration. GT-guided stereotactic endoscopic technique gives the opportunity to fenestrate the cyst wall under direct visual control.After CT-guided stereotactic puncture of the right lateral ventricle with the foramen of Monro as target a steerable endoscope is introduced and the foramen of Monro is passed. The wall of the cyst is fenestrated and coagulated by means of monopolar (or laser) coagulation.Using this technique we have treated four patients with colloid cysts. Immediately postoperatively all of them were relieved of their complaints and have been symptomfree for a mean follow up period of twelve months. Studies of cerebrospinal fluid flow patterns, performed prior to and every six months after the endoscopic intervention, confirmed a remarkable reduction of foraminal obstruction.  相似文献   
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