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991.
This research investigated the effect of head to trunk relation in a sensorimotor drawing task. In the first experiment, seated participants were asked to reproduce with eyes closed geometric shapes (square or diamond) with the tip of their right index finger in the frontoparallel plane. Their head was either aligned with the trunk or tilted 25° towards the left or right shoulder. Results showed that drawings were subjected to an overall rotation of a few degrees in the opposite direction to the tilt. In two subsequent experiments, the respective contribution of both otoliths and neck receptors to this head tilt effect was investigated. In Experiment 2, seated participants kept their head straight but were subjected to 2.5 mA vestibular galvanic stimulation (GVS). Results indicated that GVS induced a small but significant deviation of the drawings towards the anode. Finally, in Experiment 3, subjects performed the drawing task either seated upright (seated condition) or lying on their back (supine condition). Unlike in the seated condition, tilting the head towards the shoulders in a supine posture does not modulate afferents from the otolith stimulation and therefore mainly stimulates neck receptors. Head tilt induced rotations of hand-drawn reproductions in both seated and supine conditions, suggesting a significant contribution of neck afferents in the control of hand motion in space in the absence of vision. Overall the data provided evidence for a strong head-hand linkage during kinaesthetically guided drawing movements. Electronic Publication  相似文献   
992.
We describe the first fatal evolution of cellulitis due to Neisseria meningitidis serogroup Y involving an 85-year-old woman. She presented with an extensive cellulitis of the left side of the face, neck, and thorax and septic shock. In spite of active antibiotic therapy, evolution was rapidly fatal.  相似文献   
993.
The first ever case of spondylodiscitis caused by Clostridium ramosum in an elderly immunocompetent patient has been reported. C. ramosum is usually an intestinal bacterium but may occasionally be isolated in clinical specimens as an opportunistic pathogen. This report shows that this anaerobic organism can cause bone tropism without there having been any contamination due to spinal surgery. The infection cleared after empirical therapy using intravenous amoxicillin and oral metronidazole.  相似文献   
994.
We report the case of a 49-Year-old-man with primary sclerosis cholangitis (PSC) and ulcerative colitis who developed two acute episodes of pseudo-angiocholitis. Both episodes were triggered by septic hepatitis translocated from ulcerative colonic adenocarcinoma. The biliary MRI did not show any signs of lithiasis or cholangiocarcinoma. cholangiocarcinoma, intra-hepatic lithiasis and colonic cancer are potential diagnoses in patients with PSC who develop angiocholitis.  相似文献   
995.
Many critically ill and injured patients, especially those with metabolic acidosis, have abnormally high levels of unmeasured anions in their blood. At the same time, such patients are prone to hypoalbuminemia, which makes the traditional anion gap calculation inaccurate. Thus, little is known about the epidemiology and clinical consequences of an excess in unmeasured anions in the blood. Indeed, even the etiology of these "missing ions" is often unclear. Unfortunately, more precise means of quantifying unmeasured anions, such as the strong ion gap (SIG), are cumbersome to use clinically. However, a simple means of correcting the anion gap can be used to estimate SIG and may provide additional insight into this common clinical problem.  相似文献   
996.
The PIRO concept: I is for infection   总被引:2,自引:1,他引:1  
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997.
998.
There is currently great interest in the design of nanodevices that are capable of performing linear or rotary movements. Protein molecular machines are abundant in biology but it has recently been proposed that nucleic acids could also act as nanomolecular machines in model systems. Several types of movements have been described with DNA machines: rotation and "scissors-like" opening and closing. Here we show a nanomachine that is capable of an extension-contraction movement. The simple and robust device described here is composed of a single 21-base oligonucleotide and relies on a duplex-quadruplex equilibrium that may be fueled by the sequential addition of DNA single strands, generating a DNA duplex as a by-product. The interconversion between two well defined topological states induces a 5-nm two-stroke, linear motor-type movement, which is detected by fluorescence resonance energy transfer spectroscopy.  相似文献   
999.
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