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J Hatzis 《Dermatologica》1991,182(3):172-177
The primary crest surface of the healthy skin may have a smooth appearance or form a 'pavement'-like picture because of the presence of circular or polygonal subunits. In this study, the primary crest pavement structure was examined in different sites of healthy skin. The pavement structure was found in 70-100% of the adjacent areas of the palms and soles, and also on the skin of the elbows and knees. This pavement formation is absent on the skin surface of other areas or may be found in a small percentage of 5-20%. It is possible that the pavement structure could represent modified dermatoglyphics in the hairy skin.  相似文献   
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This report details the transfer of a human epidermal growth factor (hEGF) expression plasmid to porcine partial-thickness wound keratinocytes by particle-mediated DNA transfer (Accell). After gene transfer an external sealed fluid-filled wound chamber was used to protect the wound, provide containment of the exogenous DNA and expressed peptide, and permit sampling of the wound fluid. Analysis of wound fluid for hEGF and total protein, an indicator of reformation of the epithelial barrier, showed that wounds bombarded with the hEGF plasmid exhibited a 190-fold increase in EGF concentration and healed 20% (2.1 days) earlier than the controls. EGF concentrations in wound fluid persisted over the entire 10-day monitored period, decreasing from 200 pg/ml to 25 pg/ml over the first 5 days. Polymerase chain reaction results showed that plasmid DNA was present in the wound for at least 30 days. These findings demonstrate the possible utility of in vivo gene transfer to enhance epidermal repair.  相似文献   
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When observers step about their vertical axis ("active turning") without vision they dispose of essentially two sources of information that can tell them by how much they have turned: the vestibular cue which reflects head rotation in space and the "podokinesthetic" cue, a compound of leg proprioceptive afferents and efference copy signals which reflects the observer's motion relative to his support. We ask how these two cues are fused in the process leading to the perception of self-displacement during active turning. To this end we compared the performance of observers in three angular navigation tasks which differed with regard to the number and type of available motion cues: (1) Passive rotation, vestibular cue ( ves) only; observers are standing on a platform which is being rotated. (2) Treadmill stepping, podokinesthetic cue ( pod) only; observers step counter to the rotating platform so as to remain stable in space. (3) Active turning, ves and pod available; observers step around on the stationary platform. In all three tasks, angular velocity varied from trial to trial (15, 30, 60 degrees /s) but was constant during trials. Perception was probed by having the observers signal when they thought to have reached a previously instructed angular displacement, either in space or relative to the platform ("target"; range 60-1080 degrees ). Performance was quantified in terms of the targeting gain (displacement reached by the observer divided by target angle) and of the random error ( E(r)), which records an observer's deviation during single trials from his average performance. Confirming previous observations, E(r) was found to be significantly smaller during active turning than during passive turning, and we now complement these observations by showing that it is also significantly smaller than during treadmill stepping. This behaviour of E(r) is compatible with the idea that ves and pod be averaged during active turning. On the other hand, the observed characteristics of the targeting gain ( G(T)) support this idea only for the case of fast rotations (60 degrees /s); at lower velocities, the gain found during active turning was clearly not the average of the G(T) values recorded in the passive and the treadmill modes. We therefore also discuss alternative scenarios as to how ves and pod could interact, among these one based on the concept of a vestibular eigenmodel. A common denominator of these scenarios is that ves assumes the role of a prerequisite for an optimal use of pod during turning on a stationary support, without itself entering the calculation of displacement perception; this perception would be based exclusively on pod. Finally, it was a consistent observation that during passive rotations cognitive mechanisms fill in for the decaying vestibular signal in the context of the present navigation task, enabling observers to achieve large displacements surprisingly well although the duration of these movements exceeds by far the conventionally cited value of the central vestibular time constant (=20 s).  相似文献   
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Introduction: The usefulness of nasogastric aspiration and nasogastric lavage in patients with gastrointestinal bleeding is controversial, as evidenced by conflicting recommendations, both among and within society guidelines.

Areas covered: Considering these controversies, we reviewed the evidence regarding the following questions: 1) Can nasogastric lavage stop or slow down the bleeding and improve subsequent endoscopic visualization? 2) Is nasogastric aspiration helpful for the localization of bleeding? 3) Can nasogastric aspiration identify high risk patients that might benefit from earlier endoscopy? 4) Is there evidence for benefit in terms of outcomes from using nasogastric aspiration? 5) Is nasogastric intubation safe in patients with possible esophageal varices? Our review was conducted according to PRISMA guidelines.

Expert commentary: Based on the available literature, nasogastric lavage or aspiration cannot be routinely recommended unless a large properly designed randomized trial (which is currently lacking) proves otherwise. It is a painful and time-consuming procedure with no demonstrated benefit for the patient in terms of outcomes. Other clinical and laboratory parameters, and risk scores, are less invasive and are effective for guiding the stratification and management of patients, while pre-endoscopic erythromycin infusion is a good if not better alternative for improving visualization of the stomach.  相似文献   
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Summary. The epidemic of hepatitis C virus (HCV) infection is a major public health issue. We conducted a comprehensive analysis to estimate future HCV-related morbidity and mortality, using a model which is the first to take into account currently available treatments. We reconstructed the incident infections per year in the past that progressed to chronic hepatitis C (CHC) in Greece. Then, the natural history of the disease was simulated in subcohorts of newly infected subjects in the presence or absence of treatment using yearly estimates of the number of treated patients obtained from national databases. Annual estimates of the incidence and prevalence of CHC by fibrosis stage, hepatocellular carcinoma (HCC) and mortality were obtained up to 2030. The current proportion of naïve CHC patients receiving treatment in Greece is 1.2% per year. Treatment of 1.2–10% of naïve CHC patients per year would reduce the cumulative number of incident cirrhosis and HCC cases from 2002 to 2030 by 10.8–39.4% and 12.8–39.8%, respectively and decrease the number of prevalent cirrhosis and HCC cases in 2030 by approximately 17–48% compared with the number estimated under the assumption of no treatment. Approximately 17 cirrhosis cases or six HCC cases or 10 premature deaths would be prevented for every 100 treated patients. However, the prevalent cirrhotic/HCC cases because of HCV and HCV-related deaths would not plateau until 2030. Despite the introduction of effective treatment, HCV-related morbidity and mortality will likely increase during the next 20–30 years in Greece. Intensive primary prevention efforts coupled with increased access to the currently available treatments are necessary to control the chronic consequences of HCV epidemic.  相似文献   
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