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The purpose of this study was to analyze contralateral reinnervation of the facial nerve in eight patients with complete facial palsy after surgery or trauma and seven healthy volunteers. All patients had contralateral reinnervation of facial muscles as demonstrated by electrical nerve stimulation versus none of the control subjects. Four patients had facial muscle movements at the site of the damaged nerve. In one patient this was entirely the result of contralateral reinnervation, whereas the other three patients had innervation both ipsilaterally and contralaterally. This implies that renewed facial muscle activity should be examined considering the origin of the reinnervation, either contralateral or ipsilateral. Contralateral reinnervation is a common phenomenon after total facial palsy and can occur alongside ipsilateral reinnervation. It can be mistaken for adequate reinnervation of the damaged nerve, causing postponement of dynamic reconstruction therapy.  相似文献   
3.
Glucocorticoids (GCs, cortisol in human) are associated with impairments in declarative memory retrieval. Brain regions hypothesized to mediate these effects are the hippocampus and prefrontal cortex (PFC). Our aim was to use fMRI in localizing the effects of GCs during declarative memory retrieval. Therefore, we tested memory retrieval in 21 young healthy males in a randomized placebo-controlled crossover design. Participants encoded word lists containing neutral and emotional words 1 h prior to ingestion of 20 mg hydrocortisone. Memory retrieval was tested using an old/new recognition paradigm in a rapid event-related design. It was found that hydrocortisone decreased brain activity in both the hippocampus and PFC during successful retrieval of neutral words. These observations are consistent with previous animal and human studies suggesting that glucocorticoids modulate both hippocampal and prefrontal brain regions that are crucially involved in memory processing. Electronic Supplementary Material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
4.
Summary Sodium fluoride 10, 20, or 40 mg/kg body weight was given intraperitoneally to rats (6–11 days old and 90–95 days old). Blood analyses showed an initial increase in plasma fluoride concentration. The subsequent decrease in fluoride was paralleled by a decrease in total plasma calcium. These plasma concentrations were normal at blood collection 4 days after fluoride injection. The baby rats differed from the older rats in that their initial plasma calcium was higher and that the drop in plasma calcium concentration was less pronounced than in the old rats. A diet low in calcium and phosphate enhanced the effects of fluoride on total plasma calcium. The data indicate that the effect of large doses of fluoride on lowering the plasma calcium level is modified by the calcium intake.  相似文献   
5.
Three-dimensionally localized proton-decoupled phosphorus-31 magnetic resonance (MR) spectroscopy of skeletal and cardiac muscle was performed in six patients with systemic sclerosis. Cardiac (n = 9) and skeletal (n = 6) spectra were also obtained in healthy volunteers. Metabolite ratios and intracellular pH were determined from the spectra of skeletal and cardiac muscle. The phosphocreatine-to-adenosine triphosphate ratio was normal for both skeletal and cardiac muscle in patients with systemic sclerosis. The pH values of skeletal muscle were similar in patients and control subjects (7.13 ± 0.02 vs 7.12 ± 0.01, respectively). In skeletal muscle, the inorganic phosphate-to-phosphocreatine ratio in patients was increased relative to that of control subjects (0.106 ± 0.014 vs 0.086 ± 0.006, respectively; P =.02). P-31 MR spectroscopy showed no abnormalities in the myocardium of patients with systemic sclerosis. Assessment of the inorganic phosphate-to-phosphocreatine ratio in peripheral skeletal muscle may be helpful for assessing disease activity.  相似文献   
6.
In a selected group of 8 patients with progressive alopecia areata (AA) leading to AA universalis, immunological aspects (in the peripheral blood and the tissue) were studied during the period of the intitial attack of the disease. The peripheral T-cell helper/suppressor ratio appeared not to be a reliable parameter for the disease activity. The intrabulbar and peribulbar distribution of T-cells, Langerhans cells and of HLA-DR expression in and around the anagen hair follicles in the progressive areas of the disease (region of exclamation-mark hairs) may suggest a T-cell-mediated injury primarily in the peribulbar regions of the follicles. The data presented tend to support the possibility that in the early development of AA, the dermal pailla (capillary network?) may be the prime target of immunologic injury.  相似文献   
7.
Objective: Accidental injury of tissues during CO2 laser irradiation can lead to serious morbidity, especially during ear, nose, and throat, neurosurgical, and plastic-reconstructive procedures. This experimental study describes a new technique in which vital structures are coated with a thin layer of fibrin glue to protect them from accidental CO2 laser irradiation. Study Design/Materials and Methods: The femoral neurovascular bundles (femoral artery, vein, and nerve) of 12 rats were exposed. On one side the bundle was coated with fibrin glue, which is a biological two-component glue consisting of fibrinogen solution and thrombin. Upon application, an elastic mass on the neurovascular bundle was formed. The contralateral neurovascular bundle was left uncoated. Subsequently both bundles were subjected to CO2 laser irradiation at different powers (5, 7, and 9 W), with an irradiation time of 0.1 seconds. Light microscopy was performed at 30 minutes and 2 days after surgery. Results: No macroscopic visible hemorrhages occurred during laser irradiation in the glue-coated bundle. Light microscopic evaluation revealed an undamaged neurovascular bundle without any signs of thermal damage. In the uncoated bundles intraoperative hemorrhages resulting from laser energy occurred in all specimens. Furthermore, severe thermal damage was present in arteries, veins, and nerves. Conclusions: Intraoperative coating with fibrin glue can serve as a shield to protect vital structures such as arteries, veins, and nerves from accidental CO2 laser exposure. Key Words: Arteries, CO2 laser, fibrin glue, peripheral nerve, veins.  相似文献   
8.
Most dental trauma requires immediate action to preserve the affected teeth. Furthermore, the trauma has often a great impact on the appearance and well being of the patient. In this case trauma resulted in a very deep complicated crown-root fracture of one incisor and a complicated crown fracture in another incisor of a 47-year-old woman. A combination of surgical extrusion and adhesive restoration was chosen to provide good prognosis for the teeth as well as an instant esthetic result that was well accepted by the patient. Eleven months after trauma, the treated teeth exhibited good healing and normal function.  相似文献   
9.
The unit impulse response theory has been adapted to characterize the transport profile of drugs into the central nervous system (CNS). From the obtained input function, the cumulative plasma volume (V) cleared by transport into the CNS in time can be calculated. Simulation studies demonstrated that transport governed by passive diffusion resulted in a linear relationship between V and time, while the slope of the line, the blood- brain barrier (BBB) clearance, proved to be an adequate and model independent parameter to characterize drug transport into the CNS. The error in the result of the numerical procedure could be limited to less than 10% of the theoretically predicted value. Superposition of 5 or 10% random noise on simulated data did not result in significant differences between the calculated and theoretically predicted clearance values. Simulations of carrier-mediated transport resulted in nonlinear transport curves; the degree of nonlinearity, and thus the detectability, was dependent on the initial degree of saturation of the system, the rate of desaturation, as caused by drug elimination processes and the noise level on the data. In vivoexperiments in the rat were performed, using atenolol, acetaminophen, and antipyrine as model drugs. Linear transport relationships were obtained for all drugs, indicating that transport was dependent on passive diffusion or a low affinity carrier system. BBB- clearance values were 7±1 l/min for atenolol, 63±7 ul/min for acetaminiphen and 316±25 l/min for antipyrine. These experiments validate the applicability of the presented technique in in vivostudies.  相似文献   
10.
To evaluate a non-marketed research prototype of a solid-phase enzyme immunoassay for detection of herpes simplex virus in genital lesions, 154 clinical specimens were collected from 127 men and 27 women with symptoms suggestive of herpes simplex virus infection (erythema, vesicles, ulcers and crustae). The samples were tested using the assay and cultures on four monolayers of human embryonic lung fibroblasts and Vero cells. When the culture was used as reference method, sensitivity was 76.9% and specificity 100% (prevalence 42.4%). Comparison of results by patient group showed that sensitivity was highest in material from patients with vesicles and ulcers. The highest sensitivity was obtained in specimens which developed a cytopathological effect within 48 h and in specimens with three or four positive cell cultures. These findings suggest that the assay is more successful in specimens with high virus titres. The enzyme immunoassay was found to be a rapid, moderately sensitive, highly specific test for detection of herpes simplex virus from genital lesions, but the usefulness of the assay is limited and culture methods should be preferred.  相似文献   
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