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991.
R. C. Yang S. L. Yang S. L. Lai S. S. Chen C. S. Chiang 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1996,108(1):18-22
Exposure to elevated temperature provokes a sequence of events (heat shock response) in all living organisms. Through this response, heat shock proteins (HSPs) are induced and protect the cells against subsequent injury. We investigated the effect of heat treatment on bicuculline-induced convulsions, and analyzed a possible role of HSPs. Screw electrodes were implanted in the brain of mature male Wistar rats for electroencephalogram (EEG) recording. Experimental rats were subjected to whole-body hyperthermia at 41–42° C for 15 min. Fifteen hours later, bicuculline was injected intra peritoneally to induce convulsions in both experimental and control groups. The heated rats showed a significant attenuation of the convulsive response, in terms of both spike discharges in EEG and clinical seizures. Furthermore, induction of HSP72 was detected in the brain of heat-treated rats by immunoblotting, appearing at 4 h and reaching a maximal level 16–24 h after the heat shock. We conclude that the previous heat treatment stabilized neuronal excitability, most probably through the induction of HSP72. 相似文献
992.
To investigate the distribution of the Beijing family genotypes of Mycobacterium tuberculosis in Taiwan, we collected 421 M. tuberculosis complex clinical isolates at random from four geographic regions of Taiwan and analyzed them by spacer oligonucleotide typing (spoligotyping) in 2003. We found 113 resolved spoligotypes, among which we identified 28 (24.8%) clusters. One hundred eighty-seven (44.4%) isolates were Beijing family genotypes and consisted of 172 (40.9%) characteristic Beijing genotypes and 15 (3.6%) Beijing-like ones. We also found that substantially larger proportions of tuberculosis patients were infected with Beijing family genotypes in the northern (51.6%) and eastern (46.2%) regions of Taiwan, while 31.6 and 28.0% of the tuberculosis patients in the central and southern regions, respectively, were infected with these genotypes. The proportion of Beijing genotype isolates was the highest in patients below the age of 24 years (61.5%), the second highest in elderly patients over age 65 years (46.8%), and the lowest in middle-age patients between the ages of 45 and 54 years (34.0%). Geographic location and age were found by multivariate analysis to be associated with Beijing family genotypes. Antituberculosis drug resistance was found more often in Beijing family genotype strains (46.4%) than in non-Beijing family genotype strains (34.3%), with more Beijing family genotype strains being resistant to ethambutol and isoniazid. These findings suggest that M. tuberculosis Beijing family genotypes have been dominant for several decades and that they are the cause of a significant proportion of the recent transmissions of tuberculosis in Taiwan. 相似文献
993.
Encapsidation of truncated human hepatitis B virus genomes through trans-complementation of the core protein and polymerase 总被引:3,自引:0,他引:3
Mutational analyses and complementation tests were used to analyze the strategy of packaging and of replication of human hepatitis B virus (HBV). By creating new restriction enzyme sites and by varying the genome length of HBV mutants, we identified that the mutated genomes could be encapsidated through trans-complementation of the polymerase and/or core protein. This study demonstrates that the polymerase of HBV, similar to that of duck hepatitis B virus (DHBV), is synthesized de novo instead of through a core-polymerase fusion protein. The results also indicate that both the polymerase and the core protein can be supplied in trans during viral packaging, and that the complementation is not due to recombination between the cotransfected plasmids. Furthermore, HBV genome deleted down to 2.4 kb is still able to be encapsidated, as measured by the endogenous polymerase reaction. Taken together, these results provide a basis for using HBV as a vector to deliver foreign genes into hepatocytes and for defining the location of the packaging signal on the HBV genome. 相似文献
994.
Meng-Chuan Shen Hsi-Hsun Lin Susan Shin-Jung Lee Yao-Shen Chen Ping-Chen Chiang Yung-Ching Liu 《Journal of microbiology, immunology, and infection》2004,37(2):75-81
This randomized, double-blind, parallel-group study compared the efficacy and safety of famciclovir administered at 250 mg thrice daily with acyclovir 800 mg 5 times daily for the treatment of acute uncomplicated herpes zoster in immunocompetent adults. A total of 55 patients participated in this trial. Twenty seven patients (49.1%) were randomized into the famciclovir plus placebo treatment group and 28 (50.9%) into the acyclovir plus placebo group. Six of the 55 patients did not complete the study. Two of these patients were in the famciclovir plus placebo group and dropped out due to deviation from the study protocol. Four patients in the acyclovir plus placebo group did not complete the study protocol due to adverse events (n = 2), deviation from the protocol (n = 1), or loss to follow-up (n = 1). Treatment was initiated within 72 h of onset of the zoster rash and was continued for 7 days. When treatment was initiated within 72 h, famciclovir was as effective as acyclovir for healing the cutaneous lesion, as indicated by the time to full crusting, loss of acute phase pain, loss of vesicles, and loss of crusts. Famciclovir was well tolerated and had a more favorable adverse event profile compared to acyclovir. Constipation, hematuria, and glycosuria were the most commonly reported adverse events, but only constipation was considered to have a possible relationship to the treatment. In conclusion, famciclovir, administered less frequently and at lower unit doses than acyclovir, is an effective treatment for uncomplicated herpes zoster. 相似文献
995.
Computer-aided telepathology was introduced about 10 years ago, but has not yet met with worldwide acceptance. Recently, the internet has been used for image transmission in telepathology. We set up an easily assembled system comprising a common microscope, a charge-coupled device (CCD) camera, a personal computer, and a commercial internet surveillance program with internet accessibility. The consultant then views the real-time images using a common web browser at the remote site. The purpose of the study was to assess the ability of the system to transmit images of sufficient quality to achieve high concordance between the diagnoses made at the home base and at the remote site. We chose cases of minimal adenocarcinoma on prostate needle biopsy, because these lesions are liable to be overlooked and, even if discovered, are subject to differences in interpretation due to their limited size and subtle histologic changes. One hundred prostate needle biopsy specimens, including 45 minimal adenocarcinoma, 11 atypical small acinar proliferation, and 44 benign lesions, were tested. Two pathologists, unaware of the final diagnoses, were recruited to provide intra- and interinstitutional consultation. The overall concordance rates between telepathology diagnoses and final diagnoses were 97% and 94% for the two pathologists, respectively. Our results demonstrate that this method is effective for teleconsultation. Similar systems using the internet can be easily set up by ordinary pathology laboratories to facilitate remote consultation. 相似文献
996.
Chen CK Lin SK Sham PC Ball D Loh EW Hsiao CC Chiang YL Ree SC Lee CH Murray RM 《Psychological medicine》2003,33(8):1407-1414
BACKGROUND: The long-term use of methamphetamine (MAMP) can result in psychosis but it is not clear why some individuals develop psychotic symptoms, while others use MAMP regularly over long periods and remain unscathed. We set out to characterize MAMP users and to examine the relationship of pre-morbid personality, pre-morbid social function and other psychiatric disorders to MAMP psychosis. METHOD: Four hundred and forty-five amphetamine users were recruited from a psychiatric hospital and a detention centre in Taipei, and were assessed with the Diagnostic Interview for Genetic Studies (DIGS). Their parents were interviewed with the Premorbid Schizoid and Schizotypal Traits (PSST) and the Premorbid Social Adjustment (PSA) schedules. Pre-morbid characteristics and psychiatric co-morbidity were compared between the MAMP users with a lifetime diagnosis of MAMP psychosis and those without. RESULTS: The MAMP users with psychosis presented a clinical picture which mimicked the positive symptoms of schizophrenia: 85% had auditory hallucinations; 71% persecutory delusions; 63% delusions of reference. Compared with their non-psychotic counterparts, these MAMP users were younger at first MAMP use, used larger amounts of MAMP, had a significantly higher mean PSST score, and higher rates of major depressive disorder, alcohol dependence and antisocial personality disorder. CONCLUSIONS: Earlier and larger use of MAMP was associated with increased risk of psychosis. Our data are also compatible with the view that pre-morbid schizoid/schizotypal personality predisposes MAMP users to develop psychosis, and that the greater the personality vulnerability, the longer the psychosis will persist. 相似文献
997.
Chin-Hsien Lin Wuh-Liang Hwu Shu-Chuan Chiang Chun-Hwei Tai Ruey-Meei Wu 《American journal of medical genetics. Part B, Neuropsychiatric genetics》2007,(4):434-438
Recent reports suggest that CAG triplet expansions of spinocerebellar ataxia type 2 and 3 (SCA2 and SCA3) genes are the cause of typical levodopa-responsive Parkinson's disease (PD) in familial cases, several of which were ethnic Chinese. To investigate the role of SCA2 and SCA3 mutations in Chinese familial and early-onset PD patients, we analyzed CAG triplet repeat expansions of SCA2 and SCA3 genes in a cohort of 73 Taiwanese/Ethnic Chinese familial and early-onset PD patients [mean age at onset 42.70 +/- 7.17 years (mean +/- SD)]. Thirteen of them (17.8%) had positive family history. All patients received comprehensive clinical evaluation including a thorough neurological examination, laboratory tests, and neuroimaging studies to exclude secondary causes and atypical parkinsonism. The CAG repeat length in these genes was determined using polymerase chain reaction polyacrylamide gel electrophoresis. SCA2 gene CAG repeats ranged from 15 to 26 repeats with a median of 20, and SCA3 gene CAG repeats ranged from 15 to 40 with a median of 15. No long pathogenic repeats were found in either SCA2 or SCA3, although borderline CAG repeat number was detected in the SCA3 gene of four patients. Thus, mutations of SCA2 or SCA3 did not play a major role in familial or early-onset PD in our study cohort. PD patients without autosomal dominant family history or obvious cerebellar ataxia should not be candidates for routine screening of SCA2 or SCA3 mutations for cost-effectiveness. 相似文献
998.
Yu SF Wu HC Tsai WC Yen JH Chiang W Yuo CY Lu SN Chiang LC Chen CJ 《Medical microbiology and immunology》2005,194(3):115-120
Epstein-Barr virus (EBV) has been found by many serology studies to be associated with systemic lupus erythematosus (SLE). However, the results of DNA studies have been conflicting. Therefore, instead of antibody to EBV, we studied the association between EBV DNA and SLE. In this case-control study in Taiwan, we enrolled 87 SLE patients and 174 age- and sex-matched controls. Peripheral blood mononuclear cells of SLE patients and matched controls were tested for EBV DNA by polymerase chain reaction (PCR) and Southern blot. Of the 87 SLE patients, 71 (81.6%) were found to be positive for EBV DNA, while 85 (48.9%) of the 174 controls (odds ratio 4.64, 95% confidence interval 2.50–8.62, P<0.0001) were positive. While the EBV DNA-positive rate did not decline with age in SLE patients (P>0.05), it did decline with age in controls (P<0.05). Furthermore, based on a real-time quantitative PCR study, we have found a significant difference between EBV viral load in SLE and controls (P=0.008). Therefore, in our molecular study of DNA level, we found evidence for the association of EBV infection and SLE, suggesting that EBV contributes, if not to the development of SLE, then to disease perpetuation. 相似文献
999.
脉部磁场对细胞缝隙连接通讯功能影响的研究 总被引:10,自引:0,他引:10
本文用细胞内微注射法对不同强度的脉冲磁场对细胞缝隙连接通讯(GJIC)功能的效应进行了研究,并与正弦磁场的作用以及脉冲磁场所感生的不同电场的作用进行了比较和探索。研究发现0.41mT以上强度的脉冲磁场具有抑制GJIC的作用。这种作用与磁场强度有关,其抑制GJIC的效庆比正弦磁场为强。经相同磁场不同强度感应电场作用的比较。得出,GJIC的抑制主要由磁场引起,而与感应电场关系不大,本文首次从研究对GJIC的作用提供了脉冲磁场治疗的创伤愈合等有关理论依据。 相似文献
1000.
H L Chan K S Chiang D C Price J L Gardner J Brinch 《Physics in medicine and biology》1989,34(11):1609-1622
A fibre-optic hydrophone consisting of a polarisation-maintaining fibre carrying light from a laser source has been used to measure the acoustic output parameters of a single focused hyperthermia transducer and a six-transducer assembly. Beam profiles of the transducers were measured using the fibre-optic hydrophone and the results compared with those obtained using a PVDF hydrophone. The acoustic power output from the hyperthermia transducer was measured using a radiation force balance. It was observed that the root mean square voltage of the fibre-optic hydrophone output is proportional to the square root of the acoustic power up to more than 80 W. It was also observed that, under continuous-wave operation, the fibre optic hydrophone can stand up to very high power (more than 200 W) without being damaged. As its sensing element is the fibre itself, whose diameter is considerably narrower than the width of the ultrasonic beam, it can provide resolution of about 80 microm in beam profile measurement. The fibre is a line sensor and a computer tomographic technique is used to recover the pressure profile from the hydrophone output voltage. In typical clinical operations, the six-transducer assembly is driven with less than 150 W of electrical power input. In such cases, each individual transducer receives less than 25 W of input power and non-linearity and generation of high frequency harmonics at the focus is not a significant problem. 相似文献