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31.
OBJECTIVE: To examine whether promoter polymorphisms associated with variation in interleukin-10 (IL-10) production are relevant to the development of rheumatoid arthritis (RA) or Felty's syndrome (FS). METHODS: DNA was obtained from 44 FS patients, 117 RA patients and 295 controls. The promoter region between -533 and - 1120 was amplified by polymerase chain reaction, and polymorphisms detected by restriction enzyme digest or sequence-specific oligonucleotide probing. RESULTS: We found no significant difference in allele or haplotype frequencies between the groups. CONCLUSION: There is no association between FS or RA and these recently identified IL-10 promoter polymorphisms. Other genetic or environmental factors could explain the alterations in IL-10 levels seen in these conditions.   相似文献   
32.
OBJECTIVE: To estimate the frequency and correlates of undetected dementia in community-dwelling older people. DESIGN: Secondary analysis of data from the Canadian Study of Health and Aging (CSHA) prevalence survey of dementia. SETTING: All 10 provinces of Canada excluding Indian reserves and military units. PARTICIPANTS: A total of 252 community-dwelling older adults diagnosed with dementia in the CSHA survey. MAIN OUTCOME MEASURE: Undetected dementia, defined as occurring in persons who meet standard diagnostic criteria for dementia but who report never having seen a doctor for memory problems. RESULTS: Of the 252 subjects, 64% had undetected dementia. Subjects with mild functional impairment were significantly more likely to have undetected dementia (odds ratio = 2.4, 95% confidence interval 1.2, 5.0). Older subjects and those with mild cognitive impairment showed a trend toward undetected dementia, although the results did not achieve statistical significance. Educational level, number of comorbid conditions, and degree of social support were not significantly associated with undetected dementia. CONCLUSIONS: A large number of older persons are living in the community with undetected dementia. These older people may be at significant risk for delirium, motor vehicle accidents, medication errors, and financial difficulties. As preventive strategies are developed and new cognitive enhancing therapies emerge, we need to reexamine our current guidelines about screening for cognitive impairment in older adults.  相似文献   
33.
Cardiovascular pharmacology of propranolol in man   总被引:15,自引:0,他引:15  
S Wolfson  R Gorlin 《Circulation》1969,40(4):501-511
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34.
N-Dimethylisopropyl propranolol (DMP) is a quaternary derivative which lacks significant beta-adrenergic blocking and local anesthetic effects. It has been reported, nonetheless, to be effective in treating experimental arrhythmias and in limiting the extent of ST-segment elevations following experimental coronary occlusion. The present study examined the effects of DMP on the hemodynamics and myocardial oxygen demands of anesthetized dogs. After a single dose of 3 mg/kg, heart rate fell from 146 +/- 8 to 124 +/- 6 beats/min (P less than 0.0025), and aortic systolic pressure fell from 151 +/- 11 to 141 +/- 9 mm Hg (0.05 less than P less than 0.10), resulting in a 16.8% reduction in the tension-time index. Stroke volume was reduced by 10% despite a 54% increase in left ventricular end-diastolic pressure, suggesting a negative inotropic effect. This was supported by a decrease in maximum extrapolated contractile element velocity from 9.10 +/- 1.05 to 6.61 +/- 65 units/sec (P less than 0.0025). Myocardial oxygen consumption was reduced from 12.0 +/- 1.4 to 9.9 +/- 1.5 ml/min/100 g tissue (P less than 0.05). Myocardial oxygen extraction was unchanged, indicating that the decrease in oxygen consumption resulted from a reduction in myocardial oxygen demand. When heart rate and systolic pressure were artificially restored to control levels, after the administration of DMP, myocardial oxygen consumption remained significantly below the control level. DMP, therefore, appeared to reduce myocardial oxygen demands primarily by its negative inotropic effect. This drug may have application in the treatment of ischemic heart disease.  相似文献   
35.
ObjectivesCandida albicanscolonizes biomaterial surfaces and are highly resistant to therapeutics. Graphene nanocoating on titanium compromises initial biofilm formation. However, its sustained antibiofilm potential is unknown. The objective of this study was to investigate the potential of graphene nanocoating to decrease long-term fungal biofilm development and hyphae growth on titanium.MethodsGraphene nanocoating was deposited twice (TiGD) or five times (TiGV) on grade 4 titanium with vacuum assisted technique and characterized with Raman spectroscopy and atomic force microscope. The biofilm formation and hyphae growth of C. albicans was monitored for seven days by CFU, XTT, confocal, mean cell density and scanning electronic microscopy (SEM). Uncoated titanium was the Control. All tests had three independent biological samples and were performed in independent triplicates. Data was analyzed with one- or two-way ANOVA and Tukey's HSD (α = 0.05).ResultsBoth TiGD and TiGV presented less biofilms at all times points compared with Control. The confocal and SEM images revealed few adhered cells on graphene coated samples, absence of hyphae and no features of a mature biofilm architecture. The increase in number of layers of graphene nanocoating did not improve its antibiofilm potential.SignificanceThe graphene nanocoating exerted a long-term persistent inhibitory effect on the biofilm formation on titanium. The fewer cells that were able to attach on graphene coated titanium were scattered and unable to form a mature biofilm with hyphae elements. The findings open opportunities to prevent microbial attachment and proliferation on implantable materials without the use of antibiotics.  相似文献   
36.
37.
The endovenous revolution has accelerated the development of new techniques and devices for the treatment of varicose veins. The ClariVein® mechanochemical ablation device offers tumescentless treatment with a rotating ablation tip that can theoretically become stuck in tissue. We present the first report of retrograde stripping of the small saphenous vein without anaesthesia following attempted use of the ClariVein® device, without adverse sequelae.  相似文献   
38.
39.

Objective

The aim of this study was to compare the cytotoxic effects of endodontic cements on human tooth germ stem cells (hTGSCs). MTA Fillapex, a mineral trioxide aggregate (MTA)-based, salicylate resin containing root canal sealer, was compared with iRoot SP, a bioceramic sealer, and AH Plus Jet, an epoxy resin-based root canal sealer.

Material and Methods

To evaluate cytotoxicity, all materials were packed into Teflon rings (4 mmµ3 mm) and co-cultured with hTGSCs with the aid of 24-well Transwell permeable supports, which had a pore size of 0.4 µm. Coverslips were coated with MTA Fillapex, iRoot SP and AH Plus Jet and each coverslip was placed onto the bottom of one well of a six-well plate for scanning electron microscopy (SEM) analysis. Before the cytotoxicity and SEM analysis, all samples were stored at 37ºC and at 95% humidity and 5% CO2 for 24 hours to set. The cellular viability was analyzed using MTS test (3-(4,5-dimethyl-thiazol-2-yl)-5-(3-carboxy-methoxy-phenyl)-2-(4-sulfo-phenyl)-2H-tetrazolium). The cytotoxic effects and SEM visualization of the tested materials were analyzed at 24-hour, 72-hour, one-week and two-week periods.

Results

On the 1st day, only MTA Fillapex caused cytotoxicity compared to negative control (NC) group (p<0.008). No significant difference was observed between the other tested materials at this period (p>0.05). After 14 days of incubation with the test materials, MTA Fillapex exhibited significantly higher cytotoxicity compared with iRoot SP, AH Plus Jet and the NC group (P<0.008). In the SEM analysis, the highest levels of cell attachment were observed for iRoot SP and the control group. After 24 hours, MTA Fillapex reduced the number of cells attached to the surface.

Conclusions

Within the limitations of this study, sealers exerted different cytotoxic effects on hTGSCs. Although all materials have exerted cellular toxicity, iRoot SP and AH Plus Jet may promote better attachment to hTGSCs.  相似文献   
40.
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