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91.
In an attempt to establish a standardized rating system for CT of the paranasal sinuses, the Committee on Rhinology and Paranasal Sinus Disease of the American Academy of Otolaryngology-Head and Neck Surgery instituted a protocol for the review of sinus CT scans at six international sites. Fifty identical scans were rated by four otolaryngologists at each site according to five established sinus CT staging systems. Twenty of 24 reviewers repeated the rating session at least 1 week later to determine intrarater variability. The number of CT scans that could not be classified by a particular rating system ranged from 1.3% to 5.5%. The range of intrarater agreement (kappa = 0.39 to 0.74) exceeded that of interrater agreement (kappa = 0.18 to 0.49). A skewed distribution of CT scans resulted in a system with high rater agreement but poor ability to differentiate among disease states. The use of a numeric rating system to assign a score to each scan produced a comprehensive and disease-sensitive system, but one with low rater agreement. A precise definition of mucosal thickening in terms of millimeters appeared to enhance the raters' ability to assign stage and improve a system's comprehensiveness and reproducibility. On the basis of these findings, recommendations are made for the use of CT rating systems to study clinical outcomes in patients with chronic sinusitis.  相似文献   
92.
Usher syndrome is the most common form of combined deafness and blindness. The gene that is defective in Usher syndrome 1B (USH1B) encodes for an unconventional myosin, myosin VIIa. To understand the cellular function of myosin VIIa and why defects in it lead to USH1B, it is essential to determine the precise cellular and subcellular localization of the protein. We investigated the distribution of myosin VIIa in human and rodent photoreceptor cells and retinal pigment epithelium (RPE), primarily by immunoelectron microscopy, using antibodies generated against two different domains of the protein. In both human and rodent retinae, myosin VIIa was detected in the apical processes of the RPE and in the cilium of rod and cone photoreceptor cells. Immunogold label was most concentrated in the connecting cilium. Here, myosin VIIa appeared to be distributed outside the ring of doublet microtubules near the ciliary plasma membrane. These observations indicate that a major role of myosin VIIa in the retina is in the photoreceptor cilium, perhaps in such a function as trafficking newly synthesized phototransductive membrane or maintaining the diffusion barrier between the inner and outer segments. Our results support the notion that defective ciliary function is the underlying cellular abnormality that leads to cellular degeneration in Usher syndrome.  相似文献   
93.
Immunohistochemistry was used to evaluate the effects of neonatal handling and aversive stimulation during the first 10 days of life on the number of corticotrophs in the anterior lobe of the pituitary of 11-day-old male Wistar rats. Since adult rats handled during infancy respond with reduced corticosterone secretion in response to stressors and with less behavior inhibition in novel environments, we assumed that neonatal stimulation could affect pituitary morphology during this critical period of cell differentiation. Three groups of animals were studied: intact (no manipulation, N = 5), handled (N = 5) and stimulated (submitted to 3 different aversive stimuli, N = 5). The percentage of ACTH-immunoreactive cells in the anterior lobe of the pituitary (number of ACTH-stained cells divided by total number of cells) was determined by examining three slices per pituitary in which a minimum of 200 cells were counted by two independent researchers. Although animals during the neonatal period are less reactive to stress-like stimulation in terms of ACTH and corticosterone secretion, results showed that the relative number of ACTH-stained cells of neonatal handled (0.25 +/- 0.01) and aversive stimulated (0.29 +/- 0.03) rats was not significantly different from intact (0.30 +/- 0.03) animals. Neonatal stimulation may have a differential effect on the various subpopulations of corticotroph cells in the anterior pituitary.  相似文献   
94.
Gamma delta T-Cells represent a minor subpopulation of T-lymphocytes in man and their role in normal and diseased human skin is unknown. This article is a comprehensive review of T-lymphocytes bearing the gamma delta T-cell receptor in normal and pathological human skin. Firstly, we have documented the occurrence of gamma delta T-cells in normal skin and in a range of reactive and malignant skin conditions. We have then discussed the experimental findings regarding the repertoire used by gamma delta T-cells in normal human skin and in cutaneous disorders with an increased percentage of gamma delta T-cells.  相似文献   
95.
The steady-state kinetics of the ThTP hydrolysis by thiamine triphosphatase (EC 3.6.1.28) from bovine brain testified to the presence of two kinetically significant conformational states of the protein, their equilibrium being determined by the substrate concentration. The ThTPase isomeric forms had different activities, affinities for ThTP and activation energies. The form with high affinity for the substrate was characterized by the Km and Vmax values of 43 microM and 9.9 mumol.s-1.mg-1 whereas for the form with lower affinity these values were equal to 298 microM and 19.3 mumol.s-1.mg-1, respectively. The activation energies of the ThTP hydrolysis reactions were 85.3 and 47.1 kJ.mol-1. Several mechanisms of the enzyme activity regulation in the cell are suggested. One of the mechanisms is related to the allosteric ThTP effect inducing reversible transition of the protein to a more active conformational state, while the others include the inhibition activity by ATP and the activation of ThTP-ase by Mg2+ free ions.  相似文献   
96.
The paper is based on the analysis of 235 young and middle-age patients with non-traumatic cerebral hemorrhage. Tactics of treatment is determined for each group depending on bleeding localization in accordance with World Health Organization's classification (1981). Operative treatment is recommended for lateral site of hematomas of 25 cm3 and more signs of media structures dislocation of 5 mm and more. With the development of hypertension-hydrocephal syndrome surgical intervention is directed at its elimination and where possible at hematoma's ablation. The amount of operative interventions is limited in case of medial and mixed variants of hemorrhages especially when bleedings affect mesencephal structures. In conditions of a neurosurgical clinic a pharmacotherapy is used as an independent one, as a preparation for surgical treatment as well as during operation and in postoperative period.  相似文献   
97.
Operative treatment of fractures of the femur neck is the method of choice. The authors prefer the A. Seppo construction out of great number of fixtures but it is difficult to introduce and remove this fixture due to its complexity. To make the procedure of such interventions easier the authors propose a marking device, a screwdriver and a device allowing the fixture's curvature to be regulated. The modification of the technique and using a specially developed extractor is explained by difficulties in removing the fixture by common methods. The variant of the improved instrumental tooling proposed by the authors makes the operation more handy and practicable.  相似文献   
98.
The monoclonal antibodies (MAbs) against lipopolysaccharide of virulent strain of Legionella pneumophila serogroup 1 were produced. Three most productive hybrid clones (5F4, 5F10 and 2C9) were selected from fusions of mouse myeloma cells with spleen cells from BALB/c mice, immunized with bacterial outer membrane antigens. All generated clones were IgG-secreting. The MAbs had narrow strain specificity and showed no cross-reactions with other unrelated bacterial species. These antibodies were tested in sandwich ELISA. The results suggest that the MAbs could be used for diagnostic purposes.  相似文献   
99.
BACKGROUND: The infrared coagulator, a by-product of laser technology, has been used in dermatology in a variety of settings. During hair transplantation sessions, we observed a significant reduction of the donor ellipse width while performing hemostasis with the infrared coagulator. OBJECTIVE: Quantitative assessment of the donor wound width after infrared coagulator use, and correlation to the number of previous transplant sessions and patients' age. METHODS: Twenty-four patients (22 men, two women) underwent hair transplantation. The infrared coagulator was utilized for hemostasis with a pulse duration of 2.5 seconds. RESULTS: The infrared coagulator produced an average donor area decrease of 42%, while achieving rapid hemostasis. No correlation was demonstrated to number of previous transplant sessions or patients' age. CONCLUSIONS: The infrared coagulator significantly decreases the donor wound width while providing hemostasis. Advantages include the potential of larger donor strip harvest, minimal tissue manipulation, and less traumatic closure.  相似文献   
100.
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