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61.
Hypertension (HTN) and type 2 diabetes mellitus (T2DM) are emerging as epidemics of the 21st century and are important components of the metabolic syndrome (MS). Evidence demonstrates a relationship between HTN, T2DM, and several vascular and metabolic abnormalities that are components of the MS. HTN affects nearly 70 million Americans and over one billion worldwide; likewise, the MS affects 44% of the US population above the age of 60 years and is rapidly increasing. HTN associated with the MS has certain pathophysiologic characteristics that provide clinical challenges. There is growing evidence that tissue activation of the renin-angiotensin system contributes to endothelial dysfunction, microalbuminuria, insulin resistance, and subsequent increased risk for cardiovascular and chronic kidney disease. The notion that HTN is a metabolic as well as a vascular disease provides a new treatment paradigm.  相似文献   
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Mitterlechner T  Nerbl N  Herff H  Paal P  Moritz M  Kloss F  Lindner KH  Wenzel V 《Anesthesia and analgesia》2008,106(5):1505-8, table of contents
In severe airway hemorrhage, simultaneous suction and laryngoscopy may render intubation difficult. We built a suction laryngoscope that consists of an adjustable stainless steel-guide tube fixed at the lingual surface of a standard Macintosh laryngoscope blade. Via this steel-guide tube, a large suction catheter can be inserted and positioned exactly to suction pharyngeal blood or vomitus, rendering simultaneous suctioning and laryngoscopy possible. In contrast to previous suction laryngoscopes, our suction catheter has a large lumen, which enables fast suctioning and exact placement by adjusting the steel-guide tube. To assess whether our suction laryngoscope could provide better intubation conditions in comparison to a standard Macintosh laryngoscope in a bleeding airway scenario, 44 medical students intubated a manikin with severe simulated airway hemorrhage using our suction laryngoscope and a standard Macintosh laryngoscope in random order. There was no significant difference in time needed for intubation when using the suction versus the Macintosh laryngoscope (mean +/- SD: 43 +/- 13 vs 52 +/- 31 s; P = 0.07), but the number of esophageal intubations was significantly lower when using the suction laryngoscope [6 of 44 (13.6%) vs 19 of 44 (43.2%); P = 0.004]. In conclusion, when compared with a standard Macintosh laryngoscope, using a suction laryngoscope did not result in more rapid intubation, but significantly decreased the likelihood of esophageal intubations.  相似文献   
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Learning and other cognitive tasks require integrating new experiences into context. In contrast to sensory-evoked synaptic plasticity, comparatively little is known of how synaptic plasticity may be regulated by intrinsic activity in the brain, much of which can involve nonclassical modes of neuronal firing and integration. Coherent high-frequency oscillations of electrical activity in CA1 hippocampal neurons [sharp-wave ripple complexes (SPW-Rs)] functionally couple neurons into transient ensembles. These oscillations occur during slow-wave sleep or at rest. Neurons that participate in SPW-Rs are distinguished from adjacent nonparticipating neurons by firing action potentials that are initiated ectopically in the distal region of axons and propagate antidromically to the cell body. This activity is facilitated by GABAA-mediated depolarization of axons and electrotonic coupling. The possible effects of antidromic firing on synaptic strength are unknown. We find that facilitation of spontaneous SPW-Rs in hippocampal slices by increasing gap-junction coupling or by GABAA-mediated axon depolarization resulted in a reduction of synaptic strength, and electrical stimulation of axons evoked a widespread, long-lasting synaptic depression. Unlike other forms of synaptic plasticity, this synaptic depression is not dependent upon synaptic input or glutamate receptor activation, but rather requires L-type calcium channel activation and functional gap junctions. Synaptic stimulation delivered after antidromic firing, which was otherwise too weak to induce synaptic potentiation, triggered a long-lasting increase in synaptic strength. Rescaling synaptic weights in subsets of neurons firing antidromically during SPW-Rs might contribute to memory consolidation by sharpening specificity of subsequent synaptic input and promoting incorporation of novel information.  相似文献   
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We report the clinical and electron-microscopic features of endothelial cell toxicity in patients treated with hyperbaric oxygen for prolonged periods for leg ulcers. The clinical manifestations include the appearance of depressed white areas within the bed of granulation tissue, which correlated with decreased vascularity under light microscopy. Electron-microscopic findings include endothelial cells with serrated nuclear membranes and degenerate mitochondria in the cytoplasm. These changes occurred in all patients subjected to at least 8 weeks of hyperbaric oxygen, even though an intermittent regimen was adopted. The changes reversed after 1-2 weeks of cessation of hyperbaric oxygen.  相似文献   
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P. R. Issing  S. Ruh  A. Kloss  M. Kuske  T. Lenarz 《HNO》1997,45(7):545-550
Zusammenfassung Hintergrund: Die Abkl?rung raumfordernder orbitaler Prozesse erfordert neben einer modernen bildgebenden Diagnostik ein interdisziplin?res Konzept, in das der HNO-Arzt wegen der rhinochirurgischen Zugangsm?glichkeit zur Orbita unmittelbar eingebunden ist. Patienten: Innerhalb von 14 Jahren wurde bei 6 Patienten ein prim?res malignes Lymphom der Orbita sowie bei 9 Patienten ein Pseudotumor orbitae bzw. Pseudolymphom diagnostiziert. Leitsymptome waren in den meisten F?llen eine Protrusio bulbi, schmerzhafte Lidschwellung mit Diplopie und in 3 F?llen eine Visusminderung. In der bildgebenden Diagnostik lie?en sich homogene, von den Orbitastrukturen unscharf abgrenzbare Gewebevermehrung erkennen, die über eine mediale Orbitotomie biopsiert wurden. Ergebnisse: Therapeutisch wurde bei den isolierten Lymphomen eine Bestrahlung durchgeführt, w?hrend bei den Patienten mit einem „Pseudotumor orbitae” zun?chst eine Steroidgabe versucht wurde. In 2 F?llen wurde zus?tzlich eine Bestrahlung veranla?t. W?hrend es bei keinem Fall eines „Pseudotumors orbitae” zu einer malignen Transformation gekommen ist, verstarben 2 Patienten an einem sp?ter disseminierten Non-Hodgkin-Lymphom. Schlu?folgerung: Die Abgrenzung orbitaler lymphatischer Raumforderungen ist mit indirekten Verfahren nicht zuverl?ssig m?glich, weswegen in jedem unklaren Fall eine histologische Abkl?rung erforderlich ist. Je nach Lokalisation des Prozesses bietet sich hierbei ein komplikationsarmer rhinochirurgischer Zugang zur Durchführung der Biopsie und gegebenenfalls Exstirpation des Tumors an. Eingegangen am 28. Januar 1997Angenommen am 25. M?rz 1997  相似文献   
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The vaginal microbiome of healthy women is a diverse and dynamic system of various microorganisms. Any sudden change in microbe composition can increase the vaginal pH and thus lead to vaginal infections, conditions that affect a large percentage of women each year. The most common fungal strains involved in infections belong to the yeast species Candida albicans. The main virulence factor of C. albicans is the ability to transform from planktonic yeast-form cells into a filamentous form (hyphae or pseudohyphae), with the subsequent formation of biofilm. The hyphal form, constituted by filamentous cells, has the ability to invade tissue and induce inflammation. Our hypothesis is that certain polyhydroxylated carboxylic acids, that may serve as an alternative carbohydrate source and at the same time lower the pH, function as an indicator of a nutrient-rich environment for C. albicans, which favors planktonic cells over hyphae, and thus diminish the formation of biofilm. We have shown that the biofilm formation in C. albicans and other Candida species can be significantly reduced by the addition of glucono-δ-lactone (GDL).

Treatment of Candida albicans with glucono δ-lactone results in less formation of hyphae and diminish biofilm formation.  相似文献   
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