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1.
Syphilis is a sexually transmitted disease caused by Treponema pallidum. Syphilitic aortitis might coexist in a dysfunctional aortic valve, but the etiology remains unclear, because microbiological diagnosis is difficult. A 62-year-old man with low-grade fever was diagnosed with aortitis and infective endocarditis, due to Treponema pallidum infection, using polymerase chain reaction analysis. This case suggests that syphilis might cause infective endocarditis.  相似文献   
2.
In the Netherlands, safe and sufficient drinking water is provided to the general population by ten drinking water companies. To guarantee safe drinking water the World Health Organization (WHO) developed a Water Safety Plan (WSP), a Risk Assessment and a Risk Management (RA/RM) framework. The objective of the study was to identify legally required RA approaches, to document application of RA/RM activities at Dutch drinking water companies and to determine to what extent these RA/RM activities as a whole cover all the elements of the WHO WSP approach. This study could be of interest to both managers of large water utilities and decision makers.The assessment was performed by means of a policy review and interviews with two to four staff members involved in RA/RM from all ten Dutch drinking water companies combined with a joint workshop. The drinking water companies are well aware of the potential hazards and risks that can influence the drinking water quality. To guarantee the supply of safe and sufficient drinking water, the Dutch drinking water sector uses six different legally required RA/RM approaches. This study shows that by using the six legally required RA/RM approaches, all WSP steps are covered. WSP entails a generic risk assessment for identifying all hazards and hazardous events from source to tap, whereas the six legally required RA/RM each focus on specific risks at an advanced level. Each risk assessment provides information on specific hazards and hazardous events covering a part of the water supply chain. These legal requirements are complemented with additional RA/RM activities at sector and water company level such as codes of practices and standard operating procedures. The outcomes of all RA/RM approaches combined provide information from source to tap. When using multiple RA/RM approaches, it is crucial to share and combine information derived from the different activities.  相似文献   
3.
4.
A technique has been described for utilizing an existing fixed splint in the fabrication of a fixed partial denture to replace splinted teeth that are extracted.  相似文献   
5.
The independent release of adenosine and adenine nucleotides upon electrical stimulation was studied in the innervated sartorius muscle of the frog after blockade of the extracellular catabolism of adenosine monophosphate (AMP) through exo-AMP deaminase and ecto-5-nucleotidase. Nerve stimulation (30 min, 0.2Hz) induced the release of both adenosine (19±3 pmol) and adenine nucleotides (101±7 pmol). Experiments performed in the presence of tubocurarine (5 M) to prevent purine release due to nerve-evoked muscle twitching, or under direct stimulation of the muscle in low calcium solutions to prevent pre-synaptic release of purines, showed that there was an evoked release of adenosine and adenine nucleotides both from the nerve endings and from the twitching muscle fibres. Removal of ecto-5-nucleotidase inhibition shows that the catabolism of adenine nucleotides released during stimulation contributes in about 50% to the amount of endogenous extracellular adenosine. When only one of the enzymes catabolizing AMP (ecto-5-nucleotidase or exo-AMP deaminase) was inhibited, the evoked release of adenine nucleotides was undetectable, suggesting that each enzyme is able to catabolize all the AMP formed from adenine nucleotides released upon stimulation. It is concluded that the concentration of endogenous extracellular adenosine is under the control of the relative activities of exo-AMP deaminase and ecto-5-nucleotidase.Brief accounts of some of the results in this study have been published previously (refs. [6, 7]).  相似文献   
6.
The need to distinguish functional mental disorders from organic brain dysfunction has become increasingly important with the growing number of elderly patients who present with behavioral disturbances. As part of the evaluation of these patients, the psychiatrist or other physician should perform a basic neurologic examination. The author describes an examination for geriatric patients that includes methods for taking a neurologic history, for clinically measuring psychological functions, for evaluating primitive reflexes, and for interpreting peripheral neurologic responses.  相似文献   
7.
Hybrid imaging for ischemic heart disease refers to the fusion of information from a single or usually from multiple cardiovascular imaging modalities enabling synergistic assessment of the presence, the extent, and the severity of coronary atherosclerotic disease along with the hemodynamic significance of lesions and/or with evaluation of the myocardial function. A combination of coronary computed tomography angiography with myocardial perfusion imaging, such as single-photon emission computed tomography and positron emission tomography, has been adopted in several centers and implemented in international coronary artery disease management guidelines. Interest has increased in novel hybrid methods including coronary computed tomography angiography-derived fractional flow reserve and computed tomography perfusion and these techniques hold promise for the imminent diagnostic and management approaches of patients with coronary artery disease. In this review, we discuss the currently available hybrid noninvasive imaging modalities used in clinical practice, research approaches, and exciting potential future technological developments.  相似文献   
8.
目的 探讨轻中度癌痛患者的回顾性记忆(RM)与前瞻性记忆(PM)功能,了解癌痛对记忆功能的影响。方法 收集轻中度癌痛患者和健康对照者各37例,进行总体认知评估及RM和PM问卷调查。结果癌痛组简易精神状态量表得分为24.19±3.20,低于健康对照组的27.54±1.83(P<0.01);PM得分为14.76±4.53,高于健康对照组的9.59±1.38(P<0.01);癌痛组RM得分略低于健康对照组(12.78±4.27 vs. 12.91±5.12),差异无统计学意义(P>0.05)。结论 轻中度癌痛患者存在总体认知功能的损害,以记忆功能损害较为明显,其中以PM损害为主。  相似文献   
9.
To evaluate the effects of dipyridamole on blood platelet function in patients with coronary artery disease, platelet counts and aggregation were examined in aortic and coronary venous blood. Before administration of dipyridamole, platelet counts and aggregation in response to adenosine diphosphate were less (p <0.02) in coronary venous than in aortic blood. Dipyridamole administration (100 mg) resulted in an increase in platelet counts and platelet aggregation in coronary venous blood so that the differences in aortic and coronary venous blood values were eliminated. These phenomena were probably related to inhibitory actions of dipyridamole. on platelet adhesion to atherosclerotic vessels. To further study the mechanism of action, the direct effects of dipyridamole on in vitro platelet aggregation were evaluated. Although dipyridamole, in the concentrations used, had no effect on in vitro platelet aggregation, it greatly potentiated the aggregation inhibitory actions of exogenous prostacyclin. In vivo potentiation of endogenous prostacyclin and inhibitory actions on platelet adhesion are the most likely mechanisms of the potentially beneficial actions of dipyridamole.  相似文献   
10.

Objective

To compare the effects of classic progressive resistance training (PRT) versus eccentric strength-enhanced training (EST) on the performance of functional tests and different strength manifestations in the lower limb of people with multiple sclerosis (PwMS).

Design

Experimental trial.

Setting

Strength training program.

Participants

PwMS (N=52; 19 men, 33 women) belonging to MS associations from the Castilla y León, Spain.

Interventions

Participants were assigned to 1 of 2 groups: a control group that performed PRT or an experimental group that performed EST. In both groups, the knee extensor muscles were trained for 12 weeks.

Main Outcome Measures

Before and after 12 weeks of training, maximal voluntary isometric contraction and 1 repetition maximum (1RM) of the knee extensors were evaluated, as were the Chair Stand Test (CST) and Timed 8-Foot Up and Go (TUG) functional tests.

Results

No differences were found between the groups in the initial values for different tests. Intragroup comparisons found significant differences in CST (F=69.4; P<.001), TUG (F=40.0; P<.001), and 1RM (F=57.8; P<.001). For intergroup comparisons, EST presented better results than PRT in the CST (EST, 4.7%±2.8%; PRT, 1.9%±2.8%; F=13.1; P=.001) and TUG (EST, ?2.9±4.7; PRT, ?.41±5.6; F=5.6; P=.022).

Conclusions

In PwMS, EST leads to improvements in 1RM, TUG, and CST that are similar to those of PRT. However, for patients who participated in this study, the EST seems to promote a better transfer of strength adaptations to the functional tests, which are closer to daily-living activities.  相似文献   
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