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81.
Tick-borne encephalitis (TBE) virus is an important human pathogenic flavivirus that is endemic in Europe and Asia. The disease can be effectively prevented by inactivated vaccines and vaccination breakthroughs (VBTs) are rare. We investigated the characteristics of antibody responses in such VBTs in comparison to those in unvaccinated TBE patients. In contrast to the unvaccinated controls, most of the VBTs displayed a delayed IgM antibody response and had high avidity and strongly neutralizing antibodies already in the first sample taken upon hospitalization. The antibody profile of these patients therefore had the characteristics of an anamnestic immune response. In the VBTs analyzed, immunological priming and memory were apparently not sufficient or fast enough to prevent the disease. 相似文献
82.
Response rates,duration of response,and dose response effects in phase I studies of antineoplastics 总被引:4,自引:0,他引:4
Summary Over a period of 14 years, 7,960 patients were treated in 228 phase I trials. In these patients, there were 75 complete and 432 partial responses for an overall objective response rate of 6%. Complete responses lasted a median of six months (range 1–18), while partial responses lasted a median of three months (range 1–17). Of note is that no drug has made it to the market which has not had a response in phase I trials. Responses were noted in very diverse histologic types of tumors. Although there were responses at doses which were as low as 3–5% of the recommended dose for phase II trials, the majority of responses did occur at 80–120% of the dose recommended for phase II trials. Although the response rate in phase I trials is indeed low, responses do occur. This response rate information should help the clinician provide facts for the patient considering a phase I trial with new anticancer agents. These findings also emphasize that although phase I trials are characteristically dose-finding studies, if no responses are noted in phase I studies, it is unlikely the drug will be used routinely in the clinic. 相似文献
83.
A simulation study of three sequential methods for the comparison of two treatment groups when the response criterion is censored 总被引:1,自引:0,他引:1
Three recent sequential methods, group sequential analysis (GSA), the sequential probability ratio test (SPRT) and the triangular test (TT) are well suited to randomized clinical trials with a censored response criterion, as they do not require matched pairs of patients. We undertook a simulation study to investigate their statistical properties and to compare these three methods with the fixed-sample design. Our results suggest that the three methods have the expected statistical properties for size and power; they allow an important reduction of the average number of events before stopping, except with GSA when there is no treatment difference; the triangular test (closed design) appears the optimal design, as the variance of the number of events is smaller than with the sequential probability ratio test (open design) and analysis after every twenty new events does not alter the statistical properties of these sequential methods and enhances their usefulness. 相似文献
84.
Summary A double-blind, placebo-controlled study has been made of the analgesic and respiratory effects of constant rate infusions
of meptazinol and morphine in 30 patients after abdominal surgery.
Group I received meptazinol, loading dose 50 mg followed by i.v. infusion 0.5 mg · kg−1 · h−1, Group II received morphine, loading dose 5 mg and then an infusion of 0.05 mg · kg−1 · h−1, and Group III received saline.
After recovery from inhalation anaesthesia (without opiates or a local anaesthetic) pain relief and chemoreceptor carbon dioxide
tolerance were assessed before and at various times after starting the analgesic infusion. A similar degree of pain relief
was found after 10 min in Groups I and II, which lasted until the end of observation period (20 h). Heart rate and systolic
and diastolic blood pressures were lower in Group II than in Groups I and III, and respiratory rate fell in Groups I and II.
After 6 h arterial carbon dioxide tensions (PaCO2) became significantly higher in Group II than Group III. The maximum percentage fall in mean tidal volume (VT) and expired minute volume (0VE) from the preinjection values was significant in Groups I and II. End-tidal carbon-dioxide (PETCO2) and PaCO2 were significantly higher after 20 h of infusion in Group II compared to Group I. The slope of 0VE/PETCO2 (<S>) was increased in Group I and it was significantly reduced in Group II. Analysis of derived variables, such as the CO2 intercept (CO2I) and minute ventilation at 7 kPa (0VE7), indicated a shift to the right of the slopes in Groups I and II, initially more so in Group I.
It is concluded that constant rate infusions of meptazinol and morphine were effective in providing postoperative pain relief.
However, their effects on the central regulation of respiration were different, as meptazinol did not impair CO2 sensitivity whereas morphine did. 相似文献
85.
某些中枢神经元通过分叉轴突向两个以上核团投射。轴突分叉点的位置通常由计算轴突主干传导时间予以估测。但是,本工作用该法的4个公式计算细胞内或细胞外记录到的数据未能得到一致和可信的数值。结果提示,计算法的原理是不合理的,并至少对在细胞内或细胞外记录条件下估测轴突分叉点是不适用的。 相似文献
86.
FUMIHIKO YASUMA md HIROSHI HAYASHI md KAORU SHIMOKATA md MITSUHIRO YOKOTA md TAMOTSU OKADA md JUNZOH KITOH p hd 《Psychiatry and clinical neurosciences》1997,51(4):237-239
Abstract Although respiration in trained canines is well investigated, the process of preparing dogs has not been described in any great detail. Moreover, their daytime patterns of sleep and wakefulness during 1 or 2 h of electroencephalogram (EEG) and electrocardiogram (ECG) recordings are not clear. Therefore, we describe the process of selecting and training dogs, in which we recorded EEG and ECG in the laboratory. First, 14 of 1242 dogs dealt with over a 1 year period were chosen. They were trained for 2 h to lie quietly and to sleep in the laboratory; this training procedure was repeated 152 times. Three dogs were then selected and a permanent tracheostomy was performed in one. Finally, EEG and ECG were recorded with the bipolar fine needle electrodes; respiration was recorded simultaneously through a tube inserted to a tracheostomy in one dog. Wakefulness, slow wave sleep (SWS) and rapid eye movement (REM) sleep (REMS) were identified according to the EEG pattern and on the basis of the behavioral criteria. Recordings were performed 12 or 13 times in each dog. Complete sleep cycles, including wakefulness, SWS and REMS in this sequence, were observed 3.9–4.1 times. The mean duration of SWS was 2.2–4.4 min and that of REMS was 3.5–4.6 min. The REMS latency was 33.9–41.8 min. Fluctuation of heart rate with respiration, termed respiratory sinus arrhythmia, was noted in the ECG. Heart beat increased with inspiration and decreased with expiration. The present study demonstrates how to select and train sleeping dogs and shows their undisturbed daytime sleep and wakefulness patterns. 相似文献
87.
Autonomic dysfunction is frequent in patients with multiple sclerosis (MS). The sympathetic skin response (SSR) and the R-R interval variation (RRIV) are simple electrophysiologic tests for the assessment of central and peripheral autonomic disturbances. Both tests were performed in 60 patients with clinically definite MS and 30 controls. The SSR was recorded simultaneously from both upper and both lower limbs. In all volunteers normal responses were recorded from the four limbs, but 39 patients (65%) showed abnormal responses in at least one limb. The reduction in amplitude of the response was correlated with patients' EDSS. In individual limbs, the SSR amplitude correlated with weakness, spasticity and cerebellar dysfunction, but was not sufficiently related to the deep sensory loss. The RRIV was abnormal in 48 MS patients (80%), as compared to the controls, but showed no significant relationship either to the EDSS or to the SSR. The sensitivity of SSR and RRIV is high and comparable with that of visual and somatosensory evoked potentials. 相似文献
88.
T. Nishikawa H. Kuwahara A. Tsuda M. Tanaka I. Koga Y. Uchida 《Human psychopharmacology》1990,5(4):363-368
Ceruletide, a potent analogue of cholecystokinin, was administered by injection to eight schizophrenics treated with neuroleptics. We examined the dose–response effect on microvibration (MV) recorded from the chin of these patients. After 15 min of bed rest, MV was recorded for 5 min as a control recording. Subsequently, saline or ceruletide, at a dose of either 0.4 m?g/kg or at 0.8 m?g/kg, was injected according to a Latin square design with an interval of 4 weeks for washing out the drug effect and MV was recorded for 30 min. MV data obtained were subjected to the fast Fourier transform and an average power spectrum was computed. A three-way analysis of variance for these data was performed upon dose-effect, time-effect after treatment, and band-effect of the average power spectrum. The present results were similar to previous findings which had revealed effects of ceruletide on tardive dyskinesia symptoms, namely, the effects of ceruletide on MV were different according to the subjects (three cases: facilitation followed by inhibition, three cases: inhibition, two cases: no effects). The dose-response curve of ceruletide appears to be linear in some cases and an inverted U-shape in other cases. Present findings showed small doses of systemically administered ceruletide would modify muscle tonus of schizophrenics under chronic treatment of neuroleptics, and provided further reason for the therapeutic drug of tardive dyskinesia. 相似文献
89.
热休克反应对大鼠感染性脑水肿脑组织诱生型一氧化氮合酶mRNA表达的影响 总被引:1,自引:0,他引:1
:探讨热休克反应 (HSR)对百日咳杆菌所致的大鼠感染性脑水肿诱生型一氧化氮合酶 (iNOS)mRNA表达的影响。方法 :从大鼠左侧颈内动脉注入百日咳菌液制备感染性脑水肿 (感脑 )模型 ,采用组织细胞原位杂交技术检测脑组织iNOSmRNA的表达。结果 :生理盐水组、4h感脑组及 4h热休克处理组均未见iNOSmRNA表达 ,8h ,2 4h时感染性脑水肿组均有明显的杂交信号 ,以 2 4h更为明显 ;而 8h ,2 4h热休克处理组仅有少数细胞有阳性信号。结论 :热休克反应对感染性脑水肿的保护作用可能与抑制iNOSmRNA的表达有关 相似文献
90.
Jill Taylor Randall Weinberg Bernard Languet Philippe Desmettre Enzo Paoletti 《Vaccine》1988,6(6):497-503
The natural host of fowlpox virus is limited to avian species. When inoculated into non-avian tissue culture cells, however, fowlpox virus can initiate an abortive infection. A fowlpox virus was engineered to express rabies virus glycoprotein. On inoculation of the recombinant virus into either avian (permissive) or non-avian (non-permissive) cells, the rabies glycoprotein was expressed as a membrane-associated antigen. Inoculation of the fowlpox virus recombinant into six different species of mammal resulted in specific immune responses to both fowlpox antigens and to rabies glycoprotein. In mice, cats and dogs the immune response was sufficient to protect against a live rabies virus challenge. The results demonstrate the utility of a fowlpox virus vector in immunizing non-avian species against rabies in the absence of productive viral replication of the fowlpox vector. 相似文献