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101.
椎间盘部分切除对腰椎应力分布影响的有限元分析   总被引:1,自引:0,他引:1  
腰椎间盘突出症是骨科常见病之一。椎间盘切除术被广泛应用于本症的治疗。本文采用有限元素分析法观察了椎间盘部分切除前后腰椎应力分布的改变。本研究观察到,在正常情况下,椎体上下缘的中央部位承受较大的应力;椎间盘部分切除术后,椎体上下缘的侧方承采应力大于中央部分。这些结果表明,椎间盘部分切除术后可引起腰椎应力分布紊乱,出现应力集中,引起骨质增生,从而影响手术的远期疗效。  相似文献   
102.
目的对110例癫痫患者的24h动态脑电图(AEEG)的应用价值进行了初步探讨。方法使用英国的OxfordMedilog9200型8导磁带记录仪进行24h描记后作离线回放分析,并与普通EEG相比较。结果110例中AEEG异常62例(56.4%),98例中EEG发现异常32例(32.7%)。EEG正常而AEEG异常30例,EEG异常而AEEG正常9例。结论AEEG明显优于EEG,但有时AEEG也不能捕获到间歇期的发作波。分析AEEG记录必需注意将睡眠Ⅰ、Ⅱ期出现的高幅顶尖波、纺锤波与痫样波区分开来,以免导致错误诊断。AEEG对颞叶和额叶底面的致痫灶反应较差,需补做特殊电极的EEG,如蝶骨电极。  相似文献   
103.
Prevalence of hepatitis C virus antibody among Korean adults.   总被引:4,自引:0,他引:4  
To estimate the prevalence of hepatitis C virus (HCV) infection among Korean adults and to present the putative route of HCV transmission among them, serum samples from 4917 adults older than 20 years of age were tested for antibody to HCV (anti-HCV), and histories of blood transfusion and other pertinent information were obtained by self-administered questionnaires. The overall prevalence of anti-HCV was 1.7%; prevalence was 1.4% in subjects with normal levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT), 3.3% in those with slightly elevated and 5.9% in those with markedly elevated levels of the enzymes. The prevalence of anti-HCV increased with increasing age (P < 0.01), but was not associated with blood transfusion. The present study suggests that the prevalence of HCV infection was 1.4% and that the major routes of HCV transmission may be other than blood transfusion in healthy Korean adults.  相似文献   
104.
Saccharomyces cerevisiae ATS1 (-tubulin suppressor 1) was originally identified as a high-copy suppressor of class two -tubulin mutations and was proposed to have a regulatory role in coordinating the microtubule state with the cell cycle. Here, we show that Ats1p interacts with Nap1p, a cytoplasmic protein that regulates the activity of the Cdc28p/Clb2p complex. Loss of Nap1p results in a delayed switch from polar to isotropic bud growth. The delayed switch results in elongated buds. Nap1p and Ats1p interact in two-hybrid and co-immunoprecipitation assays. Both nap1 and ats1 cells have a Clb2p-dependent elongated bud morphology. Deletion of ATS1 partially suppresses the elongated bud morphology and benomyl resistance of nap1 mutants. Our results suggest Ats1p might regulate coordination of the microtubule state with the cell cycle through an interaction with Nap1p.Communicated by S. Hohmann  相似文献   
105.
乙/丙型肝炎病毒双重感染患者前C区终止变异低频率   总被引:1,自引:0,他引:1  
目的了解乙型肝炎病毒(HBV)与丙型肝炎病毒(HCV)双重感染患者前C区基因变异,及其可能的临床意义。方法用聚合酶链反应(PCR)与限制片段长度多态性(RFLP)来分析25例HBVDNA和HCVRNA均阳性(A组)和31例HBsAg和HBVDNA阳性但抗-HCV和HCVRNA均阴性(B组)的慢性肝病患者前C区密码28终止变异(终28)。结果HBV和HCV双重感染患者(A组)血清HBVDNA第1次PCR阳性率(16%)明显低于单独HBV感染组(65%)(P<0.001);前C终28检出率(28%)亦明显低于单独HBV感染(68%)(P<0.001)。结论提示双重感染患者HBV前C终止变异低频率可能与HBV低水平复制有关  相似文献   
106.
National Taiwan University College of Medicine (NTUCM) introduced small groups of teaching and basic-clinical integrated courses for medical students in 1992. By using computer network and multimedia techniques, this study tried to overcome barriers to learning in small group teaching. The Department of Medical Informatics of NTUCM established campus networking and computer classrooms and provided Internet and intranet network services including mail, netnews, bulletin board systems (BBS), world wide web (WWW), gopher, ftp and local file servers. To implement an interactive learning environment, the authors first tried mail lists, newsgroups and BBS. Next an integrated learning system prototype on the WWW was developed to provide functions including online syllabus, discussion boards simulated to BBS, online talk, interactive case studies, virtual classroom with video on demand (VOD) and Internet medical resources. The results showed that after the medical students completed the required course of medical informatics and had good network access using a network to communicate with each other became a daily practice. In the future, the system will extend to the tutoring of clinical practice and continuing medical education. The authors expect a national medical education network and more international cooperation and exchange.  相似文献   
107.
108.
BACKGROUND AND PURPOSE: Vancomycin-resistant enterococci (VRE) have emerged as important nosocomial pathogens. This study was conducted to clarify the clinical features and outcome of patients with vancomycin-resistant enterococcal bacteremia. METHODS: Patients with vancomycin-resistant enterococcal bacteremia treated at a medical center in northern Taiwan between November 1998 and July 2006 were reviewed. Clinical and bacteriological characteristics of Enterococcus faecium and Enterococcus faecalis were compared. RESULTS: Twelve patients (6 males and 6 females) were included for analyses. The mean age was 69.3 years (range, 40 to 86 years), and 8 cases (66.7%) were older than 65 years. All patients had underlying disease. Two patients received total hip replacement before development of VRE bacteremia. Twelve patients had prior exposure to broad-spectrum antimicrobial therapy. Ten patients had prior intensive care unit stay and prior mechanical ventilation before VRE bacteremia. All of the patients (n = 12) had an intravascular catheter in place. Bacteremia was caused by E. faecalis in 4 patients and by E. faecium in eight. The portals of entry included urinary tract (8.3%), skin, soft tissue and bone (41.7%) and unknown sources (50.0%). E. faecium showed a higher rate of resistance to ampicillin and teicoplanin than E. faecalis (87.5% vs 0.0%, p=0.01). The 60-day mortality rate was higher in patients with E. faecium bacteremia than E. faecalis bacteremia (62.5% vs 0.0%), although statistical significance was not obtained (p=0.08). CONCLUSIONS: VRE bacteremia may have an impact on the mortality and morbidity of hospitalized patients. Patients with bacteremia caused by vancomycin-resistant E. faecium had a grave prognosis, especially immunosuppressed patients. The prudent use of antibiotics and strict enforcement of infection control may prevent further emergence and spread of VRE.  相似文献   
109.
110.
Methicillin-resistant Staphylococcus aureus (MRSA) is an important nosocomial pathogen which has been isolated with increasing frequency in recent decades. Community-acquired MRSA (CA-MRSA) infections have also become increasingly important in recent years. This study retrospectively analyzed the risk factors, duration of hospitalization, yearly trend and seasonal variation in prevalence, and antibiotic susceptibility of isolates of community-acquired S. aureus (CASA) bacteremia and CA-MRSA bacteremia from patients treated in a teaching hospital in northern Taiwan. A total of 104 clinical isolates of CASA bacteremia were collected between January 1999 and December 2001. Among these, 35 (33.7%) were identified as MRSA. After multivariate analysis, the independent risk factors for developing CA-MRSA bacteremia were diabetes mellitus (p=0.028), chronic obstructive lung disease (p=0.037), and renal insufficiency (p=0.041). Only 6 (17.1%) patients in the MRSA group had no identified risk factors. Most of the isolates of CA-MRSA had a high degree of resistance to most antibiotics, including clindamycin (71.4%), trimethoprim-sulfamethoxazole (65.7%), and chloramphenicol (41.2%). No major trend or seasonal variation in the prevalence was found during the study period. No difference in mortality related to resistance pattern was found. Although CA-MRSA is not the major pathogen in community-acquired bacteremia, it should be included in the differential diagnosis of Gram-positive bacterial bloodstream infection, especially in those patients with risk factors. Early empiric therapy with glycopeptides in these patients may reduce morbidity and mortality.  相似文献   
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