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71.
Previous studies have demonstrated that stereocilia micromechanics change during exposure to intense stimulation, and then recover after the stimulus has ended. These changes were associated with a loss of stiffness in the sensory hair bundle. The patterns of growth and recovery in these data suggest that active cellular processes control and limit these phenomena. The present investigation further supports this suggestion. The effects of intense stereocilia stimulation were examined before and after the hair cells were metabolically blocked by cooling or by poisoning with NaCN. In normal cells threshold shift increases with exposure duration, reaching a plateau within 5 to 6 min. Moreover, a post-exposure recovery of the threshold was also noted in the control cells within 15 min. In contrast threshold shift after the first minute in the metabolically blocked cells increased monotonically during the exposure without any indication of a plateau. Similarly, no post-exposure recovery of threshold shift was seen in the stereocilia bundles. These data support the hypothesis that metabolic processes in the region of the sensory hairs are important for limiting the loss of stiffness during exposure, as well as for restoring stiffness during recovery.  相似文献   
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The sensory epithelium of the chick cochlea, the basilar papilla, contains a major protein of approximately 23,000 daltons. This protein was as abundant as actin in the papilla, yet could not be found in significant quantities in any other cochlear tissue. The protein appeared at a time in development when other studies have shown that the chick embryo develops peripheral auditory competence. These observations suggest a role for this protein in cochlear function.  相似文献   
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R A Saunders 《Ophthalmology》1986,93(8):1023-1027
Twelve patients underwent quantitated superior oblique tendon tuck and ipsilateral inferior oblique muscle myectomy in the primary treatment of unilateral superior oblique muscle palsy. Preoperatively, each patient exhibited a vertical deviation of 30-55 prism diopters in at least one position of gaze. Following a single operation, satisfactory ocular alignment was obtained in all but one case, with fusion demonstrable in clinically significant gaze positions. Eight of 12 patients had no measurable vertical deviation in primary position, and two others had residual hyperphorias of only two prism diopters. No tucks were removed for postoperative Brown's syndrome. Superior oblique tendon tuck combined with ipsilateral inferior oblique muscle myectomy appears to be a safe and effective treatment for large angle superior oblique muscle palsy.  相似文献   
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OBJECTIVE: To search for a possible correlation between incidence of postpartum depression (PPD) and any of the following factors recorded in patient charts at the routine, 4-week postnatal visit: age, breast-feeding status, smoker/nonsmoker, marital status, preexisting depression and type of delivery. STUDY DESIGN: Data were obtained from 588 obstetric charts for women who gave birth between June 1, 2003, and June 1, 2004, at 3 university clinics in Tulsa, Oklahoma. RESULTS: Prior history of depression and smoking cigarettes were significant risk factors for an Edinburgh Postnatal Depression Scale score of 13 or higher, indicating probable PPD. CONCLUSION: Our data and previous findings warrant continued investigation in a larger study to clearly delineate these and other possible risk factors for PPD and to facilitate prophylactic patient education and intervention strategies.  相似文献   
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We assessed the acceptability of three of over-the-counter products representative of potential rectal microbicide (RM) delivery systems. From 2009 to 2010, 117 HIV-uninfected males (79 %) and females (21 %) who engage in receptive anal intercourse participated in a 6-week randomized crossover acceptability trial. Participants received each of three products (enema, lubricant-filled applicator, suppository) every 2 weeks in a randomized sequence. CASI and T-ACASI scales assessed product acceptability via Likert responses. Factor analysis was used to identify underlying factors measured by each scale. Random effects models were fit to examine age and gender effects on product acceptability. Three underlying factors were identified: Satisfaction with Product Use, Sexual Pleasure, and Ease of Product Use. For acceptability, the applicator ranked highest; however, differences between product acceptability scores were greatest among females and younger participants. These findings indicate that RM delivery systems impact their acceptability and should be considered early in RM development to enhance potential use.  相似文献   
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