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排序方式: 共有307条查询结果,搜索用时 31 毫秒
1.
汪南华  王锐  冷宗康  彭司勋 《药学学报》1990,25(12):920-925
缩氨基硫脲类化合物有抗肿瘤、抗病毒和抗菌等多种药理活性。Barret等首次报道了乙二醛二缩氨基硫脲(Ⅰ)的抗疟活性。Klayman等研究了缩  相似文献   
2.
BACKGROUND: Daytime sleepiness is common in patients with sleep-disordered breathing. Although respiratory events during sleep are associated with the occurrence of daytime sleepiness, the differential impact of these events during non-rapid eye movement (NREM) and rapid eye movement (REM) sleep on daytime sleepiness has not been well characterized. STUDY OBJECTIVES: To determine the effect of respiratory events during REM sleep and NREM sleep on daytime sleepiness, as assessed by the multiple sleep latency test (MSLT). DESIGN: Cross-sectional study. SETTING: University-based sleep disorders laboratory. PARTICIPANTS: Patients referred for polysomnography and daytime MSLT (n=1,821). INTERVENTIONS: N/A MEASUREMENTS AND RESULTS: The study sample was initially divided into quartiles based on the level of the apnea-hypopnea index (AHI) during NREM sleep. Within the first NREM-AHI quartile (NREM-AHI < 8.3 events/hr), the association between REM-related respiratory events and daytime sleepiness was examined using the method of Kaplan-Meier analysis and Cox proportional hazards regression. After adjusting for age, gender, body mass index, and the duration of NREM and REM sleep, REM-AHI was not associated with daytime sleepiness (Relative Risk: 1.01; 95%CI: 0.94-1.10). Similarly, no significant association was observed between REM-AHI and the MSLT in patients within the second through fourth NREM-AHI quartiles. In contrast, increasing severity of disordered breathing during NREM sleep was associated with daytime sleepiness. For a 10-point increase in NREM-AHI, the adjusted relative risks for daytime sleepiness in the second through fourth NREM-AHI quartile were 1.21 (95%CI: 1.01-1.46), 1.20 (95%CI: 1.05-1.37), and 1.10 (95%CI: 1.04-1.16), respectively. CONCLUSION: Sleep-disordered breathing during NREM sleep, but not REM sleep, is associated with increased risk of daytime sleepiness.  相似文献   
3.
Detection of Salmonella typhi in blood by culture of the mononuclear cell-platelet layer was compared with other methods currently used for the diagnosis of typhoid fever. Colonies of S. typhi were present in all mononuclear cell-platelet layer-positive cultures within 18 h of plating and were identified within an additional 10 min by a coagglutination technique. In contrast, identification of all positive cultures by conventional blood culture required 3 days.  相似文献   
4.
A randomized double-blind trial was conducted to evaluate the safety and immunogenicity of vaccines comprised of diphtheria (D) and tetanus (T) toxoids combined with either a whole cell (P) or an acellular (aP) pertussis component and Haemophilus influenzae type b polyribosylphosphate (PRP) tetanus toxoid conjugate (PRP-T) in Indonesian infants. Three doses of either DTaP, DTaP-PRP-T, or DTP-PRP-T were administered to 930 infants approximately 2-3 months of age and at 2 month intervals thereafter. A booster dose of either DTP-PRP-T or DTaP-PRP-T was administered at 15-18 months of age. Both local and systemic reactions occurred at a significantly (p < 0.001-0.026) higher rate in the group that received whole cell pertussis vaccine versus groups which were immunized with aP containing vaccines. There was no significant difference (p > 0.05) in the rate of adverse events between groups immunized with DTaP or DTaP PRP T. One month after the third dose of vaccine, 99% of subjects had achieved > or =0.1 IU of anti-D and anti-T antibody per ml of serum. The geometric mean titer (GMT) to D was significantly (p < 0.001) higher in the group immunized with DTaP versus the other two groups whereas the anti-T GMT was significantly (p < 0.006) higher for the group immunized with DTP-PRP-T. Both the anti-pertussis toxin (PT) and anti-filamentous hemagglutinin (FHA) antibody levels were significantly (p < 0.001) higher in recipients of acellular versus whole cell pertussis vaccine. In contrast, the anti-B. pertussis agglutinating antibody response was significantly (p < 0.0001) higher in the group immunized with whole cell pertussis vaccine. The anti-PRP GMTs (microg antibody/ml) at 7 months were 0.096, 3.35 and 6.11 for groups immunized with DTaP, DTaP-PRP-T and DTP-PRP-T, respectively. The GMT for those immunized with DTP-PRP-T was significantly (p < 0.001) higher compared to recipients of DTaP-PRP-T. The percent of children who attained > or =0.15 or > or =1 microg/ml after immunization was 18 and 2% for the DTaP group, 93 and 76% for the DTaP-PRP-T group and 97 and 88% for the DTP-PRP-T group. At the > or =1 microg/ml level the difference between the DTaP-PRP0-T and DTP-PRP-T groups was significant (p < 0.01). Children immunized with either DTaP, DTaP-PRP-T, or DTP-PRP-T were reimmunized with DTaP-PRP-T whereas a portion of children immunized with DTP PRP T where also boosted with this vaccine at 15-18 months of age. There was a vigorous anamnestic response to the D and T components with all children possessing > or =0.1 IU/ml. There was also a substantial increase in anti-PT, anti-FHA and B. pertussis agglutinating antibodies. The poorest anti-PT response was seen among children receiving DTP-PRP-T for both primary and reimmunization while the highest agglutinating antibody response followed receipt of 4 doses of DTP-PRP-T. Greater than 80% of children immunized with either DTP PRP T or DTaP-PRP-T possessed > or =0.15 microg/ml before boosting versus 38% for those vaccinated with DTaP (p < 0.001). Primary immunization with DTP-PRP-T resulted in a significantly (p < 0.05) higher percentage (72%) maintaining > or =1 microg/ml compared to those immunized with DTaP-PRP-T (46%). Prior to reimmunization, the anti-PRP GMT was significantly (p < 0.005) higher for children immunized with 3 doses of DTP-PRP-T versus DTaP-PRP-T. Subsequent to reimmunization, > or =95% of subjects attained > or =1 microg/ml.  相似文献   
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Confluent cultures of endothelial cells from human umbilical cord were used to study the effect of activated human protein C (APC) on the production of plasminogen activators, plasminogen activator-inhibitor, and factor VIII-related antigen. Addition of APC to the cells in a serum-free medium did not affect the production of tissue-type plasminogen activator (t-PA) or factor VIII-related antigen; under all measured conditions, no urokinase activity was found. However, less plasminogen activator-inhibitor activity accumulated in the conditioned medium in the presence of APC. This decrease was dose dependent and could be prevented by specific anti-protein C antibodies. No decrease was observed with the zymogen protein C or with diisopropylfluorophosphate-inactivated APC. APC also decreased the t-PA inhibitor activity in endothelial cell-conditioned medium in the absence of cells, which suggests that the effect of APC is at least partly due to a direct effect of APC on the plasminogen activator- inhibitor. High concentrations of thrombin-but not of factor Xa or IXa-- had a similar effect on the t-PA inhibitor activity. The effect of APC on the plasminogen activator-inhibitor provides a new mechanism by which APC may enhance fibrinolysis. The data suggest that activation of the coagulation system may lead to a secondary increase of the fibrinolytic activity by changing the balance between plasminogen activator(s) and its (their) fast-acting inhibitor.  相似文献   
8.
The objective of this study is to examine whether increasing obstructive sleep apnea (OSA) severity is associated with worsening endothelial function. The design is a cross‐sectional examination of the baseline assessment of a multi‐centre randomized controlled clinical trial examining the effects of oxygen, continuous positive airway pressure (CPAP) therapy or lifestyle modifications on cardiovascular biomarkers. Participants were recruited from cardiology clinics at four sites. Participants with an apnea–hypopnea index (AHI) of 15–50 and known cardio/cerebrovascular disease (CVD) or CVD risk factors were included. OSA severity indices [oxygen desaturation index (ODI), AHI and percentage of sleep time below 90% oxygen saturation (total sleep time <90)] and a measure of endothelium‐mediated vasodilatation [Framingham reactive hyperaemia index (F‐RHI) derived from peripheral arterial tonometry (PAT)] were assessed. The sample included 267 individuals with a mean AHI of 25.0 ± 8.5 SD and mean F‐RHI 0.44 ± 0.38. In adjusted models, the slope of the relationship between ODI and F‐RHI differed above and below an ODI of 24.6 (= 0.04), such that above an ODI of 24.6 there was a marginally significant decline in the geometric mean of the PAT ratio by 3% [95% confidence interval (CI): 0%, 5%; = 0.05], while below this point, there was a marginally significant incline in the geometric mean of the PAT ratio by 13% (95% CI: 0%, 27%; = 0.05) per 5‐unit increase in ODI. A similar pattern was observed between AHI and F‐RHI. No relation was noted with total sleep time <90 and F‐RHI. There was evidence of a graded decline in endothelial function in association with higher levels of intermittent hypoxaemia.  相似文献   
9.

Objectives

We present our experience with a novel method for real time co‐registration of intravascular ultrasound (IVUS) and coronary angiography.

Background

A major limitation of the current practice of concomitant use of coronary angiography and IVUS is that the locations of the acquired IVUS images are not correlated with their exact locations on the vessel roadmap obtained by coronary angiography.

Methods

Phantoms simulating the coronary tree were used to test the accuracy and potential of co‐registration. Subsequently we examined patients who underwent IVUS during cardiac catheterization. Analysis and feasibility were performed in 42 arteries of 36 patients.

Results

The statistical validation in phantoms resulted in a co‐registration accuracy of 1.12 mm. The length measurement on an angiogram resulted in an accuracy of 0.38 mm. Co‐registration in patients was successful in all cases and four categories were assisted by 1(bad) to 5 (good) grading. Accuracy (the co‐registration precision in pointing at the exact corresponding location): 4.8±0.41; Ease of use and workflow: 4.74±0.44; Stent landing zone detection and evaluation: 4.58±0.5; Stent landing zone length and diameter measurement: 4.94±0.23. The co‐registration error was estimated as no more than 1 mm.

Conclusion

In this pilot study, we found that the novel IVUS and coronary angiography co‐registration method is accurate, easy to use, fast and user‐friendly. This method precludes the need to use motorized automated pull back device. (J Interven Cardiol 2016;29:225–231)
  相似文献   
10.
BACKGROUND: Understanding the association between lung function and physical performance in disabled older women helps in determining the potential for prevention and treatment strategies to decrease disability. The aim of this study was to determine the association of lung function with objective and self-reported physical performance in community-dwelling disabled older women. METHODS: The Women's Health and Aging Study I consists of 1002 disabled community-dwelling women aged > or = 65. Of these women, 840 underwent spirometry with determination of forced expiratory volume in one second (FEV1) and forced vital capacity (FVC). Cross-sectional analyses included multivariate linear regression to assess the association between FEV1, FVC, FEV1/FVC, and the time to walk four meters after adjusting for confounders, including age, race, geriatric depression scale score, body mass index, muscle strength, osteoarthritis, smoking status, and cardiovascular disease. Multiple logistic regression was used to assess the association between FEV1, FVC, FEV1/FVC, and self-reported disability in physical performance. RESULTS: FEV1 was independently associated with time to walk 4 meters. For every 100 ml decrease in FEV1, there was a 0.15-second (95% confidence interval: 0.24 to 0.06) increase in time to walk 4 meters. There was an 8% increase in the prevalent odds of self-reported disability in physical performance for every 100 ml decrease in FEV1. FVC was also associated with physical performance measures. In contrast, FEV1/FVC was associated with objective but not subjective physical performance. CONCLUSION: Decreasing lung function is independently associated with decrements in objective and self-reported physical performance in disabled older women.  相似文献   
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