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991.
992.
In a prospective study the results of a pterygium excision in 54 patients (57 eyes) who underwent a superficial free conjunctival autograft (FCG) were compared to those of patients who were treated with postoperative90Sr-irradiation. In 51 cases the minimum follow-up was six months, the maximum follow-up seven years. We divided the study up into a randomized part and an open part. In the randomized part, surgery of a primary pterygium was performed in 25 eyes, of which 16 were treated with a FCG and compared with 9 eyes with primary pterygium surgery and postoperative90Sr beta-irradiation. In the same period 16eyes were treated because of a recurrent pterygium: 8 with FCG and 8 with90Sr-irradiation. In the open part of the study16 eyes with primary pterygium were successively treated with FCG alone. The results showed in the randomized, as well as in the open study on primary surgery with a minimum follow-up of six month, one recurrence in each of the FCG-groups (2 out of 31 eyes =6.4%), and no recurrences in the 90Sr-group(0%). In the randomized group of patients treated for a recurrent pterygium one recurrence developed in the FCG group (1 out of 8 eyes =12.5%) and one in the 90Sr-group (1 out of 7 =14.6%). Analysis of other clinical parameters showed that postoperative treatment with corticosteroids, nonsteroidal anti-inflammatory drugs, and artificial tears was necessary for a longer period in the FCG group than in the90Sr-group. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
993.
Duchenne and Becker muscular dystrophies are among the most severe and frequent inherited disorders. Being still incurable, medical treatment is concentrated on the carrier diagnosis of the members of the affected families. Here we report the results of the studies of 151 members of 41 Hungarian families, obtained with multiplex PCR amplification of 18 exons as well as the muscle specific promoter region, and haplotype analysis of two polymorphic (CA)n repeat microsatellite loci in introns 45 and 49 of the dystrophin gene. The analysis of 15 deletion-type families revealed a frequency of new mutations not differing significantly from that in the other regions of Europe. We also compared the allele distributions of the two microsatellites in randomly selected normal individuals and affected family members. The allele distribution of STRP45 shows interesting differences between the two populations.  相似文献   
994.
995.
996.
Phonetics, esthetics, function, and comfort form the foundation of a successful dental prosthesis. A review of the mechanics of speech as well as common speech problems encountered with a removable maxillary prosthesis are presented. The use of a palatogram to aid the clinician in the assessment and resolution of speech problems associated with a maxillary denture is demonstrated.  相似文献   
997.
An investigation was made into the directional sensitivity of cells in the macaque anterior superior temporal polysensory region (STPa) to the motion of objects. The cells studied were sensitive to the presence of motion but showed little or no selectivity for the form of the stimulus. Directional tuning was not continuously distributed about all possible directions. The majority of cells were most responsive to motion in a direction within 15° of one of the three cartesian axes (up/down, left/right, towards/away). Tuning to direction varied in sharpness. For most (34/37) cells the angular change in direction required to reduce response to half maximal was between 45 and 70° (for 3/37 cells it was > 90°). The estimates of the directionality (median I d = 0.97) of STPa cells was similar to that reported for posterior motion processing areas (the middle temporal area, MT, and the medial superior temporal area, MST). The tuning for direction (sharpness, distribution and discrimination) of the motion-sensitive STPa cells were found to be similar to the tuning for perspective view of STPa cells selective for static form of the head and body. On average the STPa responses showed a 100- to 300-ms transient burst of activity followed by a tonic discharge maintained at approximately 20% of the peak firing rate for the duration of stimulation. The responses of motion-sensitive STPa cells occurred at an earlier latency (mean 91 ms) than responses of cells selective for static form (mean 119 ms), but the time course of responses of the two classes of cell were similar in many other respects. The early response latency and directional selectivity indicate that motion sensitivity in STPa cells derives from the dorsal visual pathway via MT/MST. The similarity of tuning for direction and perspective view within STPa may facilitate the integration of motion and form processing within this high-level brain area.  相似文献   
998.
Longitudinal growth of bone involves a complex sequence of cellular events in the cartilaginous epiphysis. Whole blood serum has been shown previously to be a potent stimulus to the cells of the growth plate, as demonstrated by its ability to activate the inositol phosphate-calcium second messenger system resulting in a rise in intracellular Ca2+. By manipulating the preparation of serum to functionally separate it into its constituent parts, we have shown that the processes of platelet lysis and activation of the clotting cascade are responsible for the generation of factors that stimulate this signaling mechanism in isolated bovine growth plate chondrocytes. Through a subsequent trial of bioactive agents generated in these processes, we identified and partially characterized several novel agonists of growth plate chondrocytes: adenosine triphosphate and adenosine diphosphate, the purine energy substrates, and bradykinin, the bioactive peptide generated in a side reaction of the clotting cascade, each induces a rise in intracellular Ca2+ via release from intracellular ion stores. Additionally, the three distinct isoforms of platelet-derived growth factor (AA, AB and BB), also released on platelet lysis, were compared with respect to their ability to stimulate the inositol phosphate-calcium second messenger system in growth plate chondrocytes.  相似文献   
999.
Background and Objective: To investigate Photofrin® (PII) and CASPc for photodynamic therapy (PDT) of the ciliary body in rabbits. Study Design/Materials and Methods: PII (10 mg/kg) or CASPc (1 mg/kg) was given by ear vein. Pharmacokinetics were studied in frozen sections by fluorescence microscopy (CCD camera based low light detection system with digital image processing) at 1 and 24 h (8 rabbits;16 eyes). Laser light was delivered (argon pumped dye laser;630 and 675 nm;8 rabbits;16 eyes) by contact fiberoptic. To compensate for iris attenuation, irradiance was 125 mW/cm2 (20, 40, 80, or 160 J/cm2). Controls (4 rabbits;8 eyes) received laser light without photochemicals (OD) and for comparison, continuous wave Nd:YAG laser by fiberoptic (0.8–1.2J;OS). Results: Localization studies showed intravascular distribution with some selective ciliary body distribution at 24 h (PII > CASPc). Rabbits treated with PII or CASPc exhibited variable amounts of gross ciliary body edema, infarction, and necrosis by 24–48 h. This response was not seen in PDT control tissues;damage was seen in the iris and ciliary body, with partial vacuolization of the pigment epithelium. Conclusion: PDT may offer a more selective approach to ciliary body destruction. A small but significant thermal effect was seen during PDT from melanin photon uptake with damage to iris and ciliary body. Thermal damage and potential interaction with ocular visual pigments may limit use of these photochemicals and wavelengths for PDT of the ciliary body © 1995 Wiley-Liss, Inc.  相似文献   
1000.
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